4
.
.
nd
->
Artim
2.
D
rei ne interpretaciones en momento entre otros en proportie
.
hur
....ihedam posit. Dat
home
SAV.,
10TH
,
.
***
,
A 608609 DUPL
DUPL
.

.

V
W
.-
...
.
.
AMANALAN
WITH
lilihiiiiii
ARTESI
V. SCIENTIA
na
OF TIME.
-
LIBRARY VERITAS
SW
-
-
-
VERSITY OF MICH
.
mitmekesimidiatimin
GANHATTATHIMTHILKINMAMILIHIHIHI..!!!
4'
UZ
.
Seni HIHUNIITDILUINITION HUMILDIDIG
sono preso
Simone
TIM HIMA
-
TIFIOR
.
المغسلسللنلنمنلننللل
MUTAN
1
MIN
A
U
STATYTYTUTTOTTTTTT
نننننننننننيبنيييينتيلية
ܚܚܚܚܚܚܚܚܚܚܚܚܚܚܚܚܚܚ
mmHIHIMANO LABAITUT
FORESTRY LIBRARY
MITTITUIT
Illll
STILLIMILIHUTUTI WIDIARRITINIMI
N
TIRIH MIHIH UHAKITUIHHHE
0
0
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
..
.
.
.
.
..
.
.
.
.
.
.
.
.
.
.
O2
.
.
.
.
.
.
.
.
.
.
Forantry
SD
445.2
.B39
THE
STRUCTURE AND CLASSIFICATION
OF BIRDS
THE
STRUCTURE AND CLASSIFICATION
OF
BIRDS
BY
FRANK E. BETDARD, M.A., F.R.S.
l'HOSECTOR AND VICE-SECRETARY 01 THE ZOOLOGICAL SOCIETY OF LONDON
LONGMANS, GREEN, AND CO.
89 PATERNOSTER ROW, LONDON
NEW YORK AND BOMBAY
1898
All rights reserver
Forcat
3-12 - buf?
57309
PREFACE
'W'e
-711
YI
13
It was the intention of my predecessor in the office of
Prosector to the Zoological Society, the late Professor
Garrod, F.R.S., to write a treatise upon bird anatomy.
This intention was so far realised that a nearly complete
No account of the anatomy of the fowl, with the appropriate
illustrations, was actually drawn up; it was proposed that
this should be followed by a second part, in which the general
anatomical characters of the different groups of birds were to
be stated. Of this second part I have beside me some thirty
sheets of MS. Professor Garrod's successor in the post of
Prosector to the Zoological Society, the late Mr. W. A.
Forbes, had every intention of finishing this work com-
menced; but unfortunately death took place before any
actual additions had been made to the MS. left by his
predecessor. I have, on the kind encouragement of Mr.
Sclater, determined to make an attempt to carry out this
plan of my two forerunners, and the present volume is the
result.
It must be admitted that a handbook upon bird anatomy
was more wanted at the time that it was first conceived by
Mr. Garrod than it is at the present day. Zoologists had
then nothing of a general character save the incompleta
fragment of Bronn's Thierreich' and the sections devoted
to bird anatomy in such comprehensive works as those of
Meckel and Cuvier. We have now two treatises of first-
rate merit, that of Fürbringer and Dr. Gadow's completion
of the section - Aves' in Bronn's "Thierreich.' Professor
TS
vi
STRUCTURE AND CLASSIFICATION OF BIRDS
Garrod’s intended work differed from either of these in that
he meant to preface it with a detailed account of Gallus. I
have not thought it useful to follow him in this; for we
have an excellent treatise dealing with one particular bird type
in Dr. Shufeldt's book upon the 'Raven. Instead of this
I commence with a general sketch of bird structure, purposely
avoiding histological detail and the elaborate description of
anatomical facts which are not, in the present state of our
knowledge, of great use in classification. The main part of
this book is the account of the structure of the different
groups of birds. It was upon this aspect of the subject that
Mr. Garrod intended to dwell most fully. Dr. Gadow has
also treated bird anatomy from this point of view; the con-
cluding section of his contribution to Bronn's Thierreich’is
devoted to an enumeration of the distinguishing characters
of the groups of birds. I have, however, treated of this
matter more fully, and have incorporated more facts (some
of them recorded for the first time) in the systematic part of
my book, than did Dr. Gadow. I have felt it to be useless
to attempt to vie with Professor Fürbringer's magnificent
treatise upon birds. To deal with all the organs of the body
as fully as he has done would require more space than it
would be probable that any publisher would be disposed to
allow me. I believe, however, that I have been able to note
the principal facts in the anatomy of the different orders of
birds, and that nothing of first-rate importance has been
omitted.
Moreover under each section I have referred to the
majority of the memoirs already published, so that the reader
can supplement, where it is necessary, the facts which I
myself detail. These references, I may remark, have been
(with a few exceptions) carefully verified; and although my
bibliography of the subject is not complete it is, I hope,
without important deficiencies.
The facts of bird structure contained in this book are to
PREFACE
I
vii
some extent drawn from published memoirs ; but the
majority of them, especially those relating to osteology and
muscular anatomy, have been verified by myself; and I have
also laid under heavy contribution the note books of my two
predecessors already mentioned. Some of the more import-
ant of these facts are illustrated by woodcuts and process'
blocks; for these I am indebted to the liberality of the
Publication Committee of the Zoological Society of London
and to the editors of the 'Ibis.'
Finally, I regret to have to acknowledge that in several
instances I have used two names for the same bird, a fact
which I did not discover in every case until it was too late
for alteration in the text. I hope, however, that any diffi-
culties arising from this error on my part will be obviated by
the cross references in the Index.
FRANK E. BEDDARD.
July 1898.
CONTENTS
Puik
.
. .
. .
..
. :
...
1
1
4
6
14
.
.
...
19
.
.
.
20
21
22
.
23
30
.
.
31
.
. :
.
. .
:
. .
.
.
33
33
34
.
THE GENERAL STRUCTURE OF BIRDS . .
THE FOOT . . . . . . . .
BEAK . . . . . . . . . .
FEATHERS . . . . . . . .
PTERYLOSIS . . . . . . . .
ALIMENTARY CANAL
Tongue . i . . . . . .
Teeth . .
Esophagus.
Stomach. .
Intestine . . . . . . . .
Cæca . . . . . . . i .
Liver . . . . . .
. .
Gall Bladder . . . . . . .
Pancreas . . . . . . . . .
Cloaca . . . . . . . .
Bursa Fabricii .
REPRODUCTION AND RENAL ORGANS . .
THE CELOM . . .
CIRCULATORY SYSTEM . . . . . .
Heart . . . . . . . . .
Arterial System :
Venous System . . . . . . .
RESPIRATORY SYSTEM.
Trachea , i ..
Syrinx . . . . . . . .
Lungs and Air Sacs ..
MUSCULAR ANATOMY . . .
Muscles of the Fore Limb . .
Muscles of the Hind Limbi
Muscles of the Neck and Trunk . . . .
Caudal Muscles . . . . . .
Abdominal Muscles .
Hyoidean Muscles . . . . . .
Muscles of the Head . . . . . .
OSTEOLOGY . . . . . . . .
.
. .
6
.
.
.
.
.
55
.
. .
58
58
.
. .
60
5
.
.
90
. 103
. . 107
108
. . 108
. 110
. . 111
.
.
.
STRUCTURE ANI) CLASSIFICATION OF BIRDS
PAGI
.
Ribs
.
.
.
.
.
.
.
.
YOT
.
.
.
·
.
.
.
.
.
.
Vertebral Column . . . . .
. . . . . . . .
The Shoulder Giralt . . . . .
The Fore Limb . . . . . .
Sternum . . . . . . .
Pelvis . . . . . . . .
Hind Limb . . . . . . .
The Skull .
BRAIN AND NERVOUS SYSTEM . . . .
THE AFFINITIES OF BIRDS . . . . .
THE CLASSIFICATION OF BIRDS . .
ORNITHURÆ . . . . . . . .
ANOMALOGONATÆ . . .
. .
PASSERES · · · · · · · ·
Pici . . . . . . . . .
Picide . . . . . . . .
Bucconidæ . . . . . . .
Rhamphastidæ
.
Capitonidze. . . . . .
ALCEDINES . ...
COLII . . . . . .
. .
TROGONES . .
CORACIÆ . .
Coraciidæ .
. . .
- Meropidæ . . . .
.
.
. .
Momotidæ .
. . . . .
Todidæ . . . . . . .
Galbulidze . . . . . . .
BUCEROTES . . . . . . .
Bucerotidæ . . . . . . .
Upupide . . . . . . .
MACROCHIRES .
CAPRIMULGI . . . . . . .
STRIGES . . . . . . . . .
PSITTACI . . . . . . . .
CUCULI . . . . . . . . .
MUSOPHAGI. . . . . . . .
OPISTHOCOMI . . . . . . . .
GALLI. . . . . . . . .
COLUMBE . . . . . . . .
PTEROCLETES . . . . . . . .
TURNICES . . . . . . . .
RALLI. . . . . . . . .
OTIDES . . . . . . . . . .
LIMICOLE . . . . . . . .
(Edicnemidal . . . . . . .
Parride . . . . . . .
.
. . 111
. . 119
. . 120
. . 123
. . 127
. . 131
. . 13:4
• 135
. . 151
. . 153
. . 159
. . 167
. . 167
· ·
172
. . 183
. . 183
. . 188
. . 189
. . 192
197
. . 201
202
20 €
. . 204
. . 208
. . 210
. . 212
. .
213
. . 215
. . 215
. .
222
.224
. . 231
. . 244
. . 253
. 272
. . 282
. . 285
. . 290
. : 30€
. . 3315
. . 319
. . 321
. . 331
. .
336
. . 345
. . 346
.
.
.
.
.
.
.
.
.
OT Q
7
.
.
.
.
.
.
.
.
.
.
.
.
.
CONTENTS
l'All
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
. . 347
. 349
. .
350
350
. 350
. . 359
366
366
369
. 373
.
.
.
.
.
.
.
.
.
374
. .
.
.
.
.
.
.
.
. . 377
378
. . 379
.
.
.
.
.
.
.
383
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
. . 386
. 392
. . 396
402
. . 419
420
.
.
.
.
Chionididæ .
Thibocoridæ
Glareolida .
Laridæ .
ALCAE . . .
GRUES . .
Gruide. .
Rhinochetidæ
Carianidæ .
Psophiidæ .
Eurypygida .
Aptornithida
Mesitidæ .
STEREORNITHES
COLYMBI . .
HESPERORNITHES
SPHENISCI . .
STEGANOPODES.
HERODIONES . .
Scopidæ .
Ciconiidæ .
Ardeidæ .
Balænicepidie .
Plataleida .
TUBINARES . .
PALAMEDEÆ .
ANSERES . .
ICHTHYORNITHES
ACCIPITRES . .
Falconida .
Pandionidae .
Serpentariidir?
Cathartidæ :
TINAMI . .
STRUTHIONES . .
#pyornithida
Dinornithidæ .
SAURURÆ . .
Saurornithes .
.
. . .
.
.
.
.
.
.
.
.
422
.
.
.
.
.
.
.
.
.
.
.
.
.
.
. 429
429
. . 433
. 434
.
.
.
.
445
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
. 451
. . 456
. 469
472
472
. . 470
. 478
479
481
. 485
. . 493
. 522
. . 523
. 529
. . 529
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
LIST OF ILLUSTRATIONS
FIG.
l'ill;
10
1. Wing of Golden Plover (after Goodchild)
. .
2. a. Cubital Remiges of Pheasant. b. Cubital Remiges of Golden
Eagle (after Wray) . . . . . . . .. 11
3. A. Manus of Ostrich, showing Attachment of Remiges. b.
Manus of Ostrich, Upper Surface, showing Remiges and
Coverts. c. Digits of Embryo, showing Remiges and Coverts
(after Wray) . . . . . . . . . . 13
4. Feather showing Aftershaft (after Sclater) . . . ...
5. A, Lower Mandible of Indian Darter. t, Radimentary Tongue.
B, Tongue in Profile (after Beddard) . . . . .
6. Head of Lorius, showing Extended Tongue with Brush Tip
(after Garrod) . . . . . . . . . .
7. Intestinal Loops (after Gadow) . . . . .
8. Alligator Mississipiensis ; Alimentary Tract (after Chalm:crs
Mitchell) . . . . . . . . . . .
9. Chauna chavaria; Alimentary Tract (after Chalmers Mitchell)
10. Argus giganteus, Chick; Intestinal Loops (after Chalmers
Mitchell) . . . . . . . . . . .
11. Casuarius ; Intestinal Tract (after Chalmers Mitchell) . .
12. Struthio camelus; Intestinal Tract (after Chalmers Mitchell)
13. Haliaetus albicilla; Intestinal Tract (after Chalmers Mitchell)
14. Ara ararauna ; Intestinal Tract (after Chalmers Mitchell).
15. Parus major (after Chalıners Mitchell) . . . . . 31
16. Alimentary Viscera of the Indian Darter (after Beddard) ...
17. Duodenum of Syrrhaptes (after Brandt) . . . . . 33
18. Duodenum, Bile Ducts, and Pancreatic Ducts of another Syr.
rhaptes (after Brandt) . . . . . . . . 33
19. Duodenal Loops of Rhea americana (after Gadow). . .
20. Duodenal Loop of Rh. Darwini (after Gadow) . . .. 34
21. Cloaca of Chauna derbiana laid open from in front (after
Forbes) . . . . . . . . . . . 35
22. Two Types of Bursa (after Forbes) . . . . . .
23. Respiratory Organs of Duck (after Huxley) . . . . 59
xiv. STRUCTURE AND CLASSIFICATION OF BIRDS
B.'lli.
J'AGE
40
5
2 1. Respiratory Organs of Apteryx (after. Huxley). . . . 39
25. Diagrammatic Transverse Section of Emu, to slow the Projec-
tion of Oblique Septum (after Beddard) . .
26. Diagram of a Transverse Section throngh Thorax of Duck
(after Beddard) . . . . . . . . . 41
27. Similar Diagram of Crow (Corvus capellanus) (after Beddaril). 41
28. Viscera of Rook displayed by Removal of Abdominal Walls
(after Beddard). . .
29. Abdominal Cavity of Bucorvus (after Beddard) . . . 44
30. Heart of Fowl, Interior of Right Ventricle (after Lankester). 49
31. Heart of Aptery.c, Interior of Right Ventricle, with Attachment
of Papillary Muscle cut through (after Lankester) . .
32. Normal Avian Carotids (after Garrod) . . . . .
33. Carotids of Bittern (after Garrod) . . . . . . 52
34. Carotids of Flamingo (after Garrod). .
35. Carotids of Cacatua (after Garrod) . . . . . . 52
36. Carotids of Passerine (after Garrod) . .
. . . 53
37. Abnormal Arrangement of Carotids, where the Left is Super-
ficial in Position (after Garrod) . . .
. .
38. Windpipe of Seleucides nigra (after Forbes) . . .
39. Breast Region of Manucodia (after Beddard). ..
40. Syrinx of Indicator, Enlarged (after Garrod) . . . . 61
41. Syrinx of Cymbirhynchus (after Forbes) . . .
42. Syrinx of Balaniceps (after Beddard). .
43. Syrinx of Struthio (after Forbes) ... . . . . 64
44. The same Syrinx from behind . . . . . . . 64
45. Syrinx of Vanella cayennensis, from in front (after Garrod).
46. The same from behind (after Garrod). .
.
47. Trachea of Tantalus loculator. a. From Front. b. From Side
(after Garrod) . . . . . . . . .
48. Syrinx of Steatornis. Front View (after Garrod) . .
49. Tensores Patagii of Phoenicopterus (after Weldon). . .
50. Muscles of Leg of Palamedea. Outer View (after Beddard
and Mitchell) . . . . . . . . . .
51. Leg Muscles of Palamedea, Inner View, illustrating Biceps and
its Sling (after Beddard and Mitchell) . . . . .
52. Leg Muscles of Balearica. The Ambiens Tendon is cut (after
Mitchell) . . . . . . . . . . .
53. Leg Muscles of Opisthocomus (after Mitchell) . . . 96
54. Flexor tendons of Gallus bankiva (after Garrod) . . 100
55. Flexor tendons of Apteryx Mantelli (after Garrod). . 100
56. Flexor tendons of Tinnunculus alaudarius (after Garrod). . 101
66
95
LIST OF ILLUSTRATIONS
XV
FIG.
1
128
?.
57. Flexor tendons of Buceros rinoceros (after. Garrod) . . 101
58. Flexor tendons of Megalcema (after Garrod) . . . . 102.
59. A Passerine Foot (after Garrod) . . . . . . 102
60. Caudal Muscles of Palamedea (after Beddard and Mitchell). 107
61. Hyoidean Muscles of Opisthocomus (after Mitchell) . . 109
62. Pelvis of Apteryx. From Beneath (after Mivart) . .. 113
63. Lumbar and Sacral Vertebræ of an Immature Ostrich (after
Mivart) . . . . . . . . . . . 113
64. Ribs, Sternum, and Pelvis of Chunga Burmeisteri (after
Beddard) . . . . . . . . . . . 114
65. Last Two Vertebræ of Struthio (aftcr Mivart). . . . 116
66. Atlas of Emu (after Mivart) . . . . . . . 118
67. Axis of Emu (after Mivart) . . . . . . . 118
68. Atlas of Cassowary (after Mivart) . . . . . . 118
69. Development of Shoulder Girdle of Chick (after Lindsay) .
70. Radius and Ulna of Metopidius (after Forbes) . . .
71. Digits of Ostrich (after Wray). . .
72. Sternum of Lophophorus impeyanus (after Huxley). ..
73. Sternum of Podica senegalensis (after Beddard) . . .
74 Sternum of Emu (after Mivart) . . . . . . . 129
75. Pelvis of Dinornis (after Mivart) . . . . . . 132
76. Hyoid of Lathamus discolor (after Mivart) i
137
77. Skull of Rhea. Ventral View (after Huxley) . . . . 140
78. Skull of Dacelo (after Huxley) . . . . . . . 140
79. Skull of Alca (after Huxley) . . . . . ... 141
80. Skull of Corvus (after Huxley) . . . . . . . 141
81. Skull of Psophia. Lateral View (after Beddard) . . . 143
82. Skull of Larus. Dorsal View (after Garrod) . . . . 143
83. Skull of Furnarius. Dorsal View (after Garroc). . 143
84. Skull of Chloephaga Magellanica. Back View (after Garrod) 146
·85. Syrinx of Eurylcemus. Front View (after Forbes). . . 178
86. Syrinx of Cymbirhynchus. Side View (after Forbes) . . 178
87. Syrinx of Philepitta. Side View (after Forbes) . . . 181
88. Syrinx of Philepitta. Front View (after Forbes) . . 181
89. Syrinx of Xenicus. A. Front View. B. Back View (after Forbcs) 181
90. Skull of Woodpecker (Gecinus viridis). Ventral View (after
Garrod) . . . . . . . . . . . . 187
91. Feather Tracts of Megalcema asiatica (after Beddard) . . 193
92. Tensores Patagii of Ceryle alcyon (after Beddarci) . . 199
93. Tensores Patagii of Callalcyon' rufa (after Beddard) . . 199
94. Tensores Patagii of Sauropatis albicilla (after Beddard) . 199
-
•
xvi
STRUCTURE AND CLASSIFICATION OF BIRDS
FIG.
PAGE
95. Skull of Colills castanonotus. Ventral Aspect (after Garrrod) 203
96. Tensores Patagii of Leptosomus (after Forbes) . . . 206
97. Syrinx of Leptosomus (after Forbes). . . .
207
98. Foot of Todus (after Forbes) . . . . . . . 213
99. Foot of Momotus (after Forbes) . . . . . . . 213
100. Patagial Muscles of Bucorvus (after Beddard) . . . 216
101. Leg Muscles of Aceros (after Beddard) . . . . . 218
102. Syrinx of Aceros nipalensis. Front View (after Beddard) . 220..
103. Syrinx of Bucorvus abyssinicus. Front View (after Beddard) 221
104. Skull of Micropus melanoleucus. Under View (after Shufeldt) 229
105. Anconal Aspect of Left Humerus of Micropus melanoleucus
(after Shufeldt) . .
. . . . . 230
106. Palmar Aspect of same Bone (after Shufeldt) . . . 230
107. Anconal Aspect of Left Humerus of Trochilus Alexandri
(after Shufeldt) . . . . . . . . . 230
108. Palınar Aspect of same Bone (after Shufeldt) . . . . 230
109. Left Feet of Antrostomus vociferus and Nyctidromus albicollis
(after Sclater) . . . . . . . . . 231
110. Right Foot of Podargus Cuvieri (after Sclater) . . . . 231
111. Powder-down Patches of Podargus (after Sclater) . . . 232
112. Pterylosis of Steatornis (after Garrod) . .
233
113. Syriox of Nyctidromus albicollis (after Beddard) . . . 235
114. Syrinx of Ægotheles (after Beddard) . . . . . . 236
115. Syrinx of Batrachostomus (after Beddard) . . . . 236
116. Patagial Muscles of Caprimulgus (after Garrod) . . . 237
117. Corresponding Muscles of Steatornis, but of Left Wing (after
Garrod). .
. . . . . . . . 237
118. Skull of Caprimulgus (after Huxlcy) . . . . . . 238
119. Fore Part of Skull of Nyctibus jamaicensis (after Huxley) 239
120. Skull of Steatornis (after Huxley) . . . . . . 239
.
.
241
. 241
2,41
122. Sternum of Caprimulgus (after Sclater) .
123. Sternum of Podargus (after Sclater) .
124. Sternum of Nyctibius (after Sclater). .
125. Colic Cæca of Photodilus (after Beddard)
126. Skulls of Strix and Bubo (after Beddard) .
127. Right Foot of Strix (after Beddard) .
128. Left Foot of Bubo (after Beddard) . .
129. Syrinx of Scops leucotis (after Beddard).
130. Syrinx of Bubo (after Beddard) . . .
131. Hyoid of Stringops (after Mivart) . .
.
.
..
.
.
247
.
. . 248
249
· .
250
.
.
.
.
. . 251
. 265
LIST OF ILLUSTRATIONS
xvii
TIG.
283
287
294
J'AGE
132. Hyoid of Lorius flavopalliatus (after Mivart) . . . . 266
133. Hyoid of Lorius domicella (after Mivart) . . . . 267
134. Pterylosis of Eudynamis orientalis. Ventral View (after
Beddard) ·
· · · · · · · · 273
135. Pterylosis of Piaya cayana. Dorsal View (after Beddard) · 274
136. Pterylosis of Piaya cayana. Ventral View (after Beddard). 275
137. Syrinx of Piaya cayana (after Beddard). . . . . 277
138. Syrinx of Centropus ateralbus (after Beddard). . .. 278
139. Intestines of Corythaix chlorochlamys (after Mitchell) . .
140. Sternum of Opisthocomus. Side View (after Huxley) .. 287
141. Sternum of Opisthocomus. Front View (after Huxley). ..
112. Syrinx of Opisthocomus. Front View (after Garrod) .. 289
143. Syrinx of Pavo spicifer. Front View (after Garrod) . .
144. Syrinx of Same. Back View (after Garrod) . . . 294
145. Syrinx of Callipepla californica. Front View (after Garroc) 295
146. Syrinx of Same. Back View (after Garrod). . . . 295
147. Syrinx of Male Tetrao tetrix. Front View (after Garrod.) 296
148. Syrinx of Aburria carunculata. Front View (after Garroc). 297
149. Syrinx of Same. Back View (after Garrod) . . . . 297
150. Syrinx of Megacephalon maleo. A. Front View. B. Back
View (after Garroc) . . . . . . . . 297
151. Skull of Crax globicera. Side View (after Huxley). .. 300
152. Skull of Tetrao urogallus. Ventral View (after Huxlcy) : 301
153. Sternum of Crax globicera (after Huxley). . i. 301
154. Horizontal Sections of Gizzards of, a, Ptilopus jambu, b, Treron
calva (after Garrod) . . . . . . . . 306
155. a, Gizzard of Carpophaga latrans. b, One of Horny Tubercles
in Section (after Garrod) . . . . . . . . 306
156. Intestines of Columba livia (after Mitchell) . . . . 307
157. Syrinx of Carpophaga latrans (after Garrod) . .
310
158. Intestines of Cariama cristata (after Mitchell) . . . 323
159. Intestines of Crex pratensis (after Mitchell) . . . . 323
160. Deep Flexor Tendons of Heliornis (after Beddard). . 326
161. Patagial Muscles of Heliornis (after Beddard). .
326
162. Syrinx of Podica senegalensis (after Beddard) . . . 327
163. Sternum of Heliornis. Ventral View (after Beddard) ..
164. Lateral View of Vertebral Column, Pelvis, and Sternum of
Podica senegalensis (after Beddard) . . . . . 328
165. Skull of Podica. Lateral View (after Beddard) . . . . 329
166. Skull of Heliornis. Ventral and Lateral Views (after Bedilard) 329
167. Skull of Podica. Ventral View (after Beddard) . . . 329
108. Under View of Skull of Charadrius pluvialis (after Huxley). 338
327
xviii STRUCTURE AND CLASSIFICATION OF BIRDS
FIG.
PAGE
349
372
373
375
169. Vomers of various Limicolæ (after Garrod) . .
339
170. Skull of Attagis Gayi (after Garrod) . . .
171. Tensores Patagii of Rhynchops (after Beddard) : . .. 352
172. Tensores Patagii of Larus argentatus (after Beddar from
Forbes) . . . . . . . . . . . 353
173. Tensores Patagii of Lunda cirrhata (after Beddard from
Forbes) . . . . . . . . . . . . 360
174. The same of Synthliborhamphus antiquus (after Beddard
from Forbes) . . . . .
. . . . 360
175. Tensores Patagii of Ceratorhina monocerata (after Beddard
from Forbes) . . . . . . . . . . 361
176. Syrinx of Lomvia troile (after Beddard). . . . . 363
177. Syrinx of Ceratorhina monoceruta (after Beddard). .. 363
178. Certain Leg Muscles of Rhinochetus (after Beddard) . . 370
179. Deep Flexor Tendons of Rhinochetus (after Beddard) .. 371
180. Muscles of Fore Limb of Rhinochetus (after. Beddard). . 372
181. Syrinx of Rhinochetus (after Beddard) . . . . .
182. Skull of Chunga. Ventral View (after Beddard) . . .
183. Syrinx of Psophia leucoptera (after Beddard) . . i.
184. Sternum, Pelvis, &c., of Psophia leucoptera (after Beddard). 376
185. Skull of Phororhacos. Lateral Aspect (after Andrcws) ..
186. Skull of Phororhacos. Dorsal Aspect (after Andrews) . .
187. Pelvis of Phororhacos. Dorsal Aspect (after Andrews) .. 385
188. Syrinx of Æchmophorus (after Beddard) . . . . 388
189. Syrinx of Tachybaptes (after Beddard) . . . . . 388
190. Origin of Biceps in Pelecanus and Phalacrocora:t (after Fair.
bringer) . . . . . . . . . . . 405
191. Skull of Fregata. Ventral Aspect (after Beddard).
192. Skull of Phaeton (after Beddard) . . . .
193. Stomach of Levaillant's Darter (after Garrod). ..
194. Syrinx of Scopus (after Beddard) . . . .
195. Deep Plantar Tendons of Scopus (after Beddard) .. 421
196. Deep Plantar Tendons of Scopus (after Beddard). . . 421
197. Syrinx of Leptoptilus (after Weldon) . . . . . .
198. Syrinx of Dissura episcopus (after Beddard) . . . .
199. Syrinx of Abdimia sphenorhyncha (after Beddard). .. 423
200. Syrinx of Xenorhynchus senegalensis (after Beddard). .
201. Convoluted Windpipe of Tantalus ibis (after Garrod) ..
202. Ventral Surface of Skull of Ardea cinerea (after Huxley) . 432
203. Syrinx of Balæniceps. Front View (after Beddard). .. 433
204. The saine. Back View (after Beddard) . . . . . 433
384
385
410
.
.
1
par
.
.
07
.
422
423
424
426
LIST OF ILLUSTRATIONS
XIX
TIG.
PAGE
449
449
453
463
205. Syrinx of Balæniceps, arranged to display Pessulus and Mem-
brana Tympaniformis (after Beddard) . . . . . 434
206. Windpipe of Platalea ajaja (after Garrod) . . . . 436
207. Intestines of Platalea leucorodia (after Mitchell) . .. 437
208. Intestines of Ciconia nigra (after Mitchell) . .
437
209. Syrinx of Phoenicopterus (after Weldon) . . . . . 440
210. Intestines of Fulmarus glacialis (after Mitchell).
446
211. Skull of Diomedea exulans (after Huxley). . .
212. Skull of Procellaria gigantea (after Huxley). . .
213. Cæca of Chauna chavaria (after Beddard). . . . .
214. Windpipe of Palamedea (after Beddard and Mitchell) . . 454
215. Skull of Chauna derbiana. Ventral Aspect (after Garrod) . 455
216. Mouth of Biziura lobata (after Forbes) . . . . . 458
217. Biceps of Femoris of Duck (Bi), to show its Relations to Gas-
trocnernius (after Weldon) . . . . . . . 460
218. Windpipe of Sarcidiornis melanota ở (after Garrod) .. 461
219. Same of S. melanota (after Garrod) . . . . . 461
220. Same of Rhodonessa caryophyllacea 4 (after Garrod) .. 461
221. Syrinx of R. caryophyllacea ở (after Garrod) . . . 462
222. Windpipe of Metopiana peposaca ó (after Garrod). ..
223. Syrinx of Biziura ở (after Forbes). . . . . .
224. Skull of Querquedula crecca. Lateral View (after Huxley). 467
225. Ventral View of Same . . . . . . . . 467
226. Tensores Patagii of Polyboroides (after Beddard). . 472
227. Tensores Patagii of Serpentarius (after Beddard) .
228. Skull of Serpentarius (after Huxley) . . .
229. Windpipe of Condor (after Beddard). .
230. Skull of Cathartes aura (after Huxley) . . . . 483
231. Cæca of Calodromas elegans (after Beddard) .
.. 488
232. Cæca of Nothura maculosa (after Beddard). . . i 488
233. Skull of Tinamus robustus (after Huxley) . . . . . 490
234. Tongue and Windpipe of Rhea Darwini (after Gadow). 505
235. Syrinx of Apteryx Mantelli. Front View (after Forbes) .. 507
236. The same, from behind . . . . . . . .
237. Syrinx of Rhea americana. Front View (after Forbes) .. 508
238. The same, from behind . . . . . . . . 508
239. Syrinx of Casuarius galeatus. Front View (after Horbes). . 509
240. The same, from behind . . . . . . . . 509
241. Tracheal Pouch of Emu cut open (after Murie). . . ...
242. Sternum of Rhea (after Mivarl) . . . . . . 512
243. Pelvis of Rhea (after Mivart) . . . . . . . 513
507
XX
STRUCTURE AND CLASSIFICATION OF BIRDS
WIG.
Pirit
.
244. Skull of Emu (after Huxley) . . . . . . . 514
245. Pelvis of Emu (after Mivart) . . . . . . . 515
246. Sternum of Cassowary (after Mivart) . . . . . 516
247. Pelvis of Cassowary (after Mivart) . .
248. Skull of Ostrich (after Huxley) . . . . . . 518
249. Sternum of Ostrich (after Mivárt) . . . . . . 519
250. Pelvis of Ostrich (after Mivart) i ..
. . . . 519
251. Shoulder Girdle of Æpyornis (after Andrews) . . . . 523
252. Diagram of Relationships of Struthiones (after T. J. Parker) 527
THE
STRUCTURE AND CLASSIFICATION
OF
BIRDS
THE GENERAL STRUCTURE OF BIRDS
As the aim of the present work is to detail the characteristics
of the various groups of birds, I do not propose in this
section to do more than give a general account of bird
anatomy. A fuller description will be found in the part
relating to birds by Dr. GADOW, in Bronn's 'Klassen und
Ordnungen des Thierreichs,' where much that will be found
here in the accounts of the several families of birds is
treated of in the introductory chapters. The greater part of
this I deliberately omit, to save repetition.
The Foot
The feet of birds show a large amount of variation,
which is not for the most part of great value in the deter-
mination of affinities. That the older naturalists paid great
attention to these facts is evident from the names Palmipedes,
Cursores, &c. No bird has, save for abnormalities, such as
the Dorking fowl, more than four toes. The opposite ex-
treme is reached by the ostrich, which has only two. That
the three-toed and, a fortiori, the two-toed condition has
been arrived at by a reduction from four toes seems to be
shown by the condition of the feet in certain petrels, where,
2
STRUCTURE AND CLASSIFICATION OF BIRDS
as shown by FORBES, a rudiment of the missing toe is
present in the shape of a nodule, or of two nodules, of bone,
hidden in extreme cases beneath the skin, and only appear-
ing externally as a small wart with no claw. In Phebætria
there is an advance upon this, since there is externally a
minute claw, and beneath the skin two minute nodules of
bone. In the woodpeckers, Picoides and Tiga, commonly
spoken of as three-toed birds, there is a similar vestige of
the fourth toe. On the other hand this does not apply to
all three-toed birds. In Rhea, Tetrax, and Pelecanoides
FORBES searched in vain for a trace of the missing toe. The
toes of the bird's foot are arranged in different fashions,
giving rise to more than one form of foot. When there are
only three toes they are all directed forwards, except in
Picoides, where the last is directed backwards ; but then, as
already stated, this bird has a rudimentary hallux, and it
conforms therefore to the type seen in other woodpeckers.
When there are four toes they are rarely all turned forwards;
this is the case, however, with the swifts. Most commonly
the hallux is turned more or less completely backwards ;
this is so with the passerines and with many other birds.
In what is termed the zygodactyle foot, e.g. the woodpeckers,
both the first and the fourth toes are turned backwards, and
thus an effective grasping organ is produced.
An anomalous form of zygodactylism, termed hetero-
dactylism by some, is offered by the trogons, where the
second toe is turned back. Syndactylism is an expression
used to describe toes which are united together for a longer
or shorter distance, such as, for example, the todies and
kingfishers. Further details in the form of foot will be
found under the descriptions of the several families.
In many birds the toes are perfectly free from each other
up to their attachment to the metatarsals. In others there
is a condition known as webbing, where a scale-covered
skin is stretched between the toes. This may be feebly
developed, as in many wading birds, or complete, as in swim-
ming birds, such as the duck. The extreme state of webbing
is seen in the pelican tribe, where all the four toes are
THE FOOT
CU UY
united by webs—in the ducks only three being thus united,
and the hallux free. The coots have a form of webbing
which is characterised by applying the term 'lobate' to the
foot. Each toe in the case of a lobate foot is bordered by a
flat expansion of skin, but there is no connection between
the borders of adjacent toes. The foot is covered to a vary.
ing degree with a horny integument, which is arranged as
larger or smaller flat scales, or as granules of various shapes
and sizes. This scutellation sometimes extends on to the
tibia ; it generally occupies the tarsus as well as the foot
proper ; the other extreme is shown by Syrrhaptes, where
feathering extends down to the last digits of the foot. The
form of these is sometimes useful in classification, as in the
Passeres (q.v.) The digits are armed with claws, which are
straighter in wading birds, and very curved in the birds of
prey. Their relative lengths vary ; in the larks, for example,
and in the cuckoo (Centropus) that of the hind toe is enor-
mously long. The middle toe is often serrated, as in herons,
owls, and goatsuckers, &c.
The order of the toes may be almost always settled by
counting the number of the phalanges. This is progressive,
the first toe having two phalanges, the second three, the
third four, and the fourth five. To this general rule there
are a few exceptions. I have described in the owl (Photo-
dilus) only four phalanges in the last (fourth toe), a state of
affairs, however, which is plainly due to a fusion between
the two first phalanges. The goatsuckers (of genus Capri-
mulgus and allied forms) have a digital formula of 2, 3, 4, 4.
In many Tubinares the formula is 1, 3, 4, 5. In the swifts
the toes are still further reduced, for we have in that group
the digital formula 2, 3, 3, 3. Pterocles has a digital formula
agreeing with that of Caprimulgus. ZEHNTNER' has lately
shown that the digital formula of the swifts is due to
reduction ; he has found, in fact, in Cypselus melba, in a
certain stage of development, four phalanges in each of
digits 3 and 4, in which stage, therefore, the bird is only
one digit short of the normal.
1 Beiträge zur Entwicklung von Cypselus melba, Arch. f. Naturg. 1890.
1
B
2
STRUCTURE AND CLASSIFICATION OF BIRDS
A comparison of the varied forms of feet among birds
has an important bearing upon the origin of the foot. From
this follows some insight into the nature of the life led by
the possessors of the most primitive form of foot. The
matter has been put forward in a clear fashion by FINN,
and in a correspondence which his paper elicited. As all the
evidence at our disposal seems to show that the four-toed
foot is the more primitive, we have to decide whether the
palmate foot of the pelicans or the grasping foot of the
passerine is the earlier, or whether some modification of
these, such as the zygodactyle, or four-toed foot with a
rudimentary hallux, is the more primitive. The four-toed
foot of the Steganopodes is often figured as if all the toes were
directed forwards, but this is really not the case; they are,
as in terrestrial birds with a more or less rudimentary
hallux, directed at least sideways. This seems to argue that
the original form of the foot was as it is now in the Passeres,
a fact which is still further enforced by the foot of Archæo-
pteryx (see below). The more purely terrestrial the birds are
the more rudimentary is the hallux, until in the purely
terrestrial bustards the hallux has disappeared altogether,
and in the ostrich, most terrestrial of birds, the second toe
the more arboreal forms, the Cracidæ and Megapodidæ, the
hallux is better developed than in those that do not roost in
trees. That the zygodactyle foot is a further modification of
the anisodactyle seems to be shown by the transitional state
of the owls, which always perch in the zygodactyle position,'
the fourth toe being capable of reversion.?
Beak
In all existing birds the upper and lower mandibles are
invested with a horny sheath, the beak. The form of this
| 'The Significance of the Bird's Foot,' Natural Science, June 1894 ; see
also July and September Nos. of the same periodical for further notes and
correspondence on the matter.
? A. REICHENOW, ' Die Fussbildungen der Vögel, J. f. O. 1871, p. 401.
BEAK
beak has been used by ornithologists for systematic purposes,
and whole groups of birds have received their names from
this shape, e.g. dentirostres, lamellirostres, &c. The bill,
however, varies so greatly in admittedly allied birds that its
use for classificatory purposes is not great. As a striking
instance of this may be mentioned the Limicolæ ; we see
there the spatulate bill of Euonyrhynchus, like a diminutive
spoonbill, the upturned bill of Recurvirostra, the sideways-
turned bill of Anarhrynchus, the longer lower mandible of
Rhynchops, and the ibis-like bill of Numenius. GADOW has
used for classificatory purposes the complex or simple con-
dition of the beak. In some birds, e.g. Ratitæ, the horny
sheath is composed of several pieces; in others, the majority,
this is not the case. In birds of prey and in parrots there
is present a structure which has been termed the cere : this
is simply the basal part of the beak, which has remained soft.
Its occurrence in those two groups of birds does not appear
to be significant of any close affinity.
The lamellirostres afford another example of how dan-
gerous it is to attempt any decision as to affinities from the
form of this organ. It has been insisted that one reason for
regarding the flamingo as a long-legged duck is the existence
of lamellæ along the beak; but this feature is also met with
in the stork, Anastomus, to which group moreover the bird
is now more generally believed to be related. The puffin is
nearly exceptionall in the periodical moulting of a portion of
the bill; but the pelican (P. trachyrhynchus) casts annually
an excrescence upon the top of the upper beak. Sexual
dimorphism in the bill is rare, but is exhibited in a marked
way in Heteralocha, where the female has a long and down-
wardly curved bill, while that of the male is shorter and
straighter.?
? Several auks (q.v.) do so, and it has been asserted of the penguins.
2 See in this matter and for variations EHLERS, Zool. Miscell. i. (Göttingen,
1894).
6
STRUCTURE AND CLASSIFICATION OF BIRDS
Feathers 1
A bird may be known by its feathers; to define a bird it
is only necessary to refer to its covering of feathers. No
other animal has any structures comparable to a well-
developed feather. It is true that the filo-plumes are really
little more than hairs. But the processes of development
serve to place a fundamental barrier between the two kinds
of structures.
A hair commences as a thickening of the stratum
Malpighii, which grows downwards into the dermis ; a feather
is from the first a slight papilla involving the outer layers of
the epidermis as well as the stratum Malpighii, a papilla
which is surrounded by a circular depression. This papilla
gradually sinks down into the skin and assumes a cylindrical
form. The cells of the Malpighian layer commence to pro-
liferate vigorously, and form a series of thickened folds
disposed radially to the longitudinal axis of the feather
arranged masses of cells undergo a process of cornification, ·
free themselves from the overlying cells of the horny layer of
the epidermis, and produce a bundle of horny fibres, the
embryonic down. The feathers may retain this embryonic
character throughout life, or further changes may take place.
This consists in the formation below the first feather follicle
of a second in continuity with it; in this a feather is
developed, which may be a down feather, like the first formed,
or may grow into one of the stronger varieties of feathers to
be described presently.. In either case the growing feather
pushes the down before it, and the latter is ultimately thrown
off.
The structure of feathers has been described at length by
| H.R. DAVIES, ' Beitrag zur Entwicklungsgeschichte der Feder,' Morph. J.B.
xiv. 1888, p. 368, and · Die Entwicklungsgesch. d. Feder,' &c. ibid. xv. 1889,
p. 560; C. R. HENNICKE, ' Die Entwicklung d. Feder,' Monatsschr. deutsch. Ver.
Vogelsch. xiv. 1889, p. 223; K. KLEE, ‘Bau und Entwicklung der Feder,'
Zeitschr. f. d. ges. Naturw. lix. p. 110 ; see also GADOW, article · Feather' iu
NEWTON'S Dict. of Birds.
FEATHERS
NITZSCH, and among recent writers more especially by
WRAY.! A typical feather consists of the stem or rhachis,
of which the lower 'quill’ region is termed the calamus.
From the rhachis above the calamus spring a series of lateral
branches, the rami or barbs, which in turn give rise to
barbules, and they to minute, often hooked, processes, the
barbicels. At the junction of the calamus with the barb-
bearing rhachis arises in many feathers an aftershaft (fig.
4), which has the character of a second smaller feather
arising from the shaft of the first; but in the cassowary,
emu, and the extinct Dinornis this aftershaft is as large as
the main feather from which it arises. The barbicels with
their terminal hamuli give the stiffness to the feather which
is caused by the interlocking of these processes. The bar-
bules are of two sorts, those nearest to the root of the barb
being different from those nearest to its tip. The former
are shaped something like a knife blade; they are thickened
above and bent in the middle, gradually tapering away to
a fine point; just in the middle, where the bend is, are
two or three small teeth on the upper margin. It is by
means of these teeth that successive barbules are locked
together. The remaining set of barbules are frayed out.
towards the end into a series of branchlets which are
hooked at first, but the more distal set are merely fine-
pointed branchlets; these arise obliquely, so that a given
barbule comes into relation with four or five other barbules.
All feathers, however, have not so complicated a structure..
The strong wing feathers of the cassowary consist of the
stem alone. Filoplumes have but few radii, consisting
almost alone of the calamus and rhachis.
Down feathers are as a rule without the hamuli ; often
the radii spring at once from the calamus, there being
no rhachis. A peculiar form of these feathers, called
T'On the Structure of the Barbs, Barbules, and Barbicels of a Typical
Pennaceous Feather,' Ibis, 1887, p. 420.
? The term neossoptiles has been applied to the down covering the newly
hatched young of many birds, in contradistinction to teleoptiles, the feathers.
(down or contour) of the adult bird.
8
OF BIRDS
T
STRUCTURE AND CLASSIFICATION powder down feathers,'l is found in many birds belonging
to quite different groups; they are usually aggregated into
special patches. These are simply down feathers of which
the tops continually break down into a dusty matter.
These powder down patches have been asserted to be lumi-
nous in the heron, and to aid it in attracting its prey ; but
the assertion seems to be void of truth.
The feathers of birds are, with a few exceptions, coloured
either by the deposition of pigments alone, or by optical
tints derived from the actual structure of the feathers shown
up against a basis of dark pigment. The colours of birds’
feathers have been chiefly investigated by CHURCH, KRUKEN-
BERG, and GADOW,2 to whose papers the reader is referred.
The arrangement of the feathers upon the wing requires
a special description. They have been carefully studied by
the late Mr. WRAY,3 from whose paper both the informa-
tion and some of the explanatory illustrations have been
drawn. In the wing of the wild duck there is, as in all
birds, a fringe of stout quills known as the remiges. These
are attached to the fore-arm and to the hand. The border
of the ulna, to which they are fixed, constantly bears impres-
sions of the quills. Here the feathers stand out at right
angles to the bone; in the hand they become more and
more inclined forwards until the last of the series lies parallel
with the bone (phalanx 2 of digit II.) which bears it. Of
these remiges it is usual to term those which are inserted
upon the ulna the secondaries, and those upon the hand
proper primaries. But the term cubitals is gaining ground
as an expression for the secondaries of many writers. The
first of the remiges is much smaller than the others, and
has been called the remicle ; it nevertheless belongs to the
series of remiges. The rest of the feathers of the wing are
known as the coverts or tectrices. There are four series of
L. STIEDA, Über den Bau der Puderdunen der Rohrdrommel,' Arch. f.
Anat. 1. Phys. 1870, p. 104.
Gadow, in Bronn's Thierreich (“Aves ’), treats of the matter in considerable
detail.
3. On some points in the Morphology of the Wing of Birds, P.Z. S. 1887
P. 343.
FEATHERS
these, which successively overlap each other and the remiges..
The first series on the upper aspect of the wing are the
tectrices majores, which have a perfectly definite relation to
the remiges, there being one for each remex. To this state-
ment there is in the duck a single exception; this exception
is the fifth cubital (reckoning, as it is customary to do, from
the carpus) ; this remex appears, by reason of the fact that
there is a gap and that the tectrix is present, to be absent.
On the under surface of the wing there is a corresponding
row of lower tectrices majores. It will be noticed that the
reference of the remicle to the series remiges is justified by
its having its proper complement of tectrices majores.
Next to the tectrices majores comes a row of feathers,
the tectrices medie. These are also present on the under
surface; the set of both, however, is not complete, that of
the second metacarpal being wanting on the upper surface,
and the distal four or five of the manus on the lower surface.
The next row on the upper face of the wing is quintuple,
and the feathers composing the five tiers are known as
the tectrices minores. They are scantily represented on
the manus, where in fact there is not room for them, they
being developed on the skin covering the muscles and on
the patagium of the wing. This row of feathers passes on
to the humerus and becomes there partly specialised into
two rows; the lower of these (sometimes called parapteron)
are long feathers suggestive of remiges, while the row im-
mediately above bears the same relation to the pseudo-
remiges as the tectrices majores do to the true remiges. On
the ventral surface of the wing are similar tectrices minores
with a similar specialisation of an hypopteron (representing
the parapteron above, and sometimes called axillaries), with
its row of special coverts. The patagium is mainly filled
up with several rows of feathers, which are collectively
termed the marginals; anteriorly, upon the pollex, they
form together with the anterior feathers of the minores the
so-called ala spuria. The ala spuria is specialised into four
small quills with coverts, the specialisation being quite like
that of the humerals at the other extremity of the wing.
VO
10 STRUCTURE AND CLASSIFICATION OF BIRDS
So much then for the arrangement of the feathers in the
typical bird selected; we must now consider the divergencies
from this constituted normal. The fifth cubital, absent in

......?!
Fig. 1.-WING OF GOLDEN PLOVER AFTER GOODCHILD).
1-1', posterior border ; 2-2, anterior border; d, rewiges ; B, greater wing coverts ; C, D,
, median coverts; E, F, remaining coverts.
the wild duck, is often present in birds. The terms 'quin-
cubital' and 'aquincubital' have been devised to express
these facts. The following groups are quincubital: 1
Crypturi, Galli, Rhinochetidæ, Cuculi, many Picarians.
On the other hand aquincubital birds are-
· Colymbidæ, Tubinares, Steganopodes, Herodiones, Acci-
pitres, Anseres, &c.
The majority of birds, in fact, have not the fifth cubital
remex. The most remarkable fact about this missing
remex is that it is either absent or present ; in no case are
there any intermediate conditions, such as a small remex.
See SCLATER, ' Remarks on the Fifth Cubital Remex,' &c.. Ibis (6), ii. 1890,
p. 77.
FEATHERS
11
The only explanation, so far as I am aware, of this
remarkable state of affairs is contained in a suggestive paper
by DEGEN. DEGEN commences with the assumption that in
the hands of the primitive bird all three fingers—then freely
movable-were furnished with remiges. In modern birds
remiges are only attached to the thumb (ala spuria) and to
digit II. DEGEN also postulates a fourth finger (of which
rudiments have been discovered in modern birds; see below)
with its remiges.
When the metacarpal bones became fused the feathers
of the third and fourth digits were, he supposed, forced back
1
2


Love
HA
it
!
FI
f
..
ANT
YN
BU
212
.
CAZA
YO
.
.
LISTA
.
.
-
US
..
his
YA
...
.
NWU-
//
Ver
.
.
..
.
.
2
S
.
.
so
FE.
vet
MA
VATTIOS
LEO
NE
20
IM
SA
M
Isus.
15!
!
WALLOWASILISHI
HAVE
WEAR
VUUR
-CO-
OS.
ti..
G
UI
UZ
FIG. 2.-A. CUBITAL REMIGES OF PHEASANT. 6. CUBITAL REMIGES
OF GOLDEN EAGLE (AFTER WRAY).
R 1-7, remiges ; D.C, dorsal tectrix major ; II, ulna.
upon the ulna, as there was no longer any room for their
coexistence with those of the second digit upon the com-
pressed hand. Among these the carpal remex was also
pushed back. As this remex was attached to an unstable
bone or cartilage, its position was not secured, and the varia-
bility remained when the feather altered its position ; hence
the presence or absence of the fifth remex, which is this
feather.
The carpal remex is another variable feather. It is present
T.On some of the Main Features in the Evolution of the Bird's Wing,' Bull.
Brit. Orn. Club, July 1894 (published in Ibis). See also for quincubitalism
GERBE, 'Sur les Plumes de Vol et leur Mue, Bull. Soc. Zool. I'r. ii. 1877,
p. 289.
12
STRUCTURE AND CLASSIFICATION OF BIRDS
and fully-sized in Nothura. It is occasionally present but
small, and sometimes even with its covert altogether absent.
The remiges themselves vary in number apart from the
presence or absence of the fifth cubital, but not within
very wide limits. Struthio and the penguin alone are
exceptional, and will be treated of separately and later.
GADOW has published a useful table showing the number of
the primaries in a very large assortment of birds belonging
to all orders. The number of primaries varies only between
ten and twelve. The number of metacarpals has also a
small range of variation, the smallest number presenting
six and the largest eight. Casuarius having an abbreviated
hand is still further reduced, the primaries being only two
and the secondaries five. The largest number of metacarpals,
eight, is possessed, however, by Apteryx, with an abbreviated
hand, and by Struthio. Seven metacarpals are found in the
grebes, flamingoes, and several, but not all, the genera of
· storks. All other birds have six.
The two prominent exceptions to the foregoing state-
ments are, as has been already mentioned, Struthio and the
Spheniscidæ. In the ostrich (see fig. 3) there are sixteen
primaries, each with its tectrix major upon the upper surface
of the wing. The other rows are perfectly recognisable, as is
shown in the figure. The wing of the penguin is, however,
not reconcilable with the ordinary plan of structure. It has
thirty-six bordering feathers, which may be termed primaries;
FÜRBRINGER has suggested that these may be really ten
primaries with their coverts, but in any case the wing is
covered with about thirty rows of scale-like feathers.
As to the general wing feathering, GOODCHILD' has sur-
veyed a large series of birds, and noted their peculiarities.
Some valuable classificatory results appear to be the outcome
of these investigations. Thus the plan characteristic of the
humming birds resembles that of the swifts, and both are to
be distinguished from the passerines. The picarian type
gradually approximates to the psittacine; Melopsittacus
1. Observations on the Disposition of the Cubital Coverts in Birds,' P. Z. S.
1886, p. 184.
FEATHERS
13
might be well referred to the picarians when judged from
the present standpoint. On the other side the birds of prey,
both diurnal and nocturnal, are parrot-like in the arrange-
.
.
.
.....
.
TAKA
.
***
*
**
**
ASS
.
S
.
.
.
/
.
...
IX.
..
X
0
.
.
35
:
T
.
A
LIS
A:
ve
14
/ Claw
T..ma
IL
YUVY.
IV
Ph3
SRL
AL
d
YOU
EYOR
centrs
IR NE
6.:L
10
XIA
4
.
NA
Ꮲd .
M
.
MS
Z
MES
WW
.
.
V
1
.
-
.
U
"/ 21
.
.
LV
Vrh
.
**
ai
WE,
an m
.
SUS
GO
.
Sa
.
-
1
,00
i
.
INVASHA
.
22.
AM
www .
..
.
.
.
.
.
Md.
TI
102,
ve
SARNAS
AN
COS
..
Pj Prz
..
JAR
..
.
.
.
.
p
EIN
SENA
:::::11
12
PRO
AN
BA
.
..
.
WANAWAASARAY
.
.
!
.
TV
*
.
S
.
1.
VE
UN ..
. . . .
NEV
mi
FIG. 3.-a. Manus or OSTRICH, SHOWING ATTACHMENT OF REMIGES. 1. Manus or OSTRICH, UPPER SURFACE,
SHOWING REMIGES AND COVERTS. C. DIGITS or EMBRYO, SHOWING REMIGES AND COVERTS. (AFTER WRAY.)
Hal-3. metacarpals: Ph, phalauges ; I-III, digits ; C, carpal remes; M, metacarpal remiges ; D, digital remiges; Ad, addigitals;
Md, middigitals; Pil, predigitals; 7. Mj, tectrices majores; .Md, tectrices mediæ ; T.Mn, tectrices minores; (M), marginals;
al, ala spuria ; a', tectrices majores,

.
..
.
.
1+
.
SA
WV
.
.
VI
1
I
.
I
.
.
PL.
SU
SORRY
SYSAS
Ad
M
www
.
.
INS
:
1
.
W
...
1
.
.
NOSSO
SIN
1:1)
8
.
MC3
T!
i
be
T.Mn
05
N
Kiti 1
IN
.
IN
an eines
.
i
Y
A
5
NAS
VINY
WW
BURU
Synt
NY
WA
X
LLE
20
A
VAR
.
6
1..
2
Iclal
.
'
Ph.2
ALWAYA
MANUSIA
1
le
S
:/
Ġ
SITE:
GO2017r.
27
IM
.
...
..........
-----OPO
WOLI
22.
COM
VI
Z
,..).
Hr
U21 24
. 11:27
Mc2
Phz |
MY
.
!
Y
.
port
Tava
WS
!..
SV
SALA
..
..-
-.
.
WIN
RESORT
METAR
BUSCA
Wil WMA
..
E
.
z
SA
5
KA
Tit.
3
.
NR
"
ZA
I
(WV)
T
-
TER
2
ION
1:
V2:
IL
M
SR:
..
b
::
-
.
SUZU:n.
..
-
.
SUV
I
.
-
1. SI
. .
:.
::
:::
Hotel
Me
in
LY
S
..
7.Ma
ment of their wing feathers. But, curiously enough, Pernis,
Pandion, Gypogeranus, and the Cathartidæ differ from their
allies. This is not the only case where the disposition
of the feathers runs counter to the affinities to be
14
STRUCTURE AND CLASSIFICATION OF BIRDS
derived from an examination of other structures; for
while Phalacrocorax is quite accipitrine the other Stega-
nopodes are quite different. Herons agree with the
Accipitres, while the ciconiine pattern leads towards that
of the Tubinares, and is identical in some cases with that of
the American vultures. The cuckoos should be, when
judged by the feathering of their wings, placed in the
immediate neighbourhood of the Columbæ, from which group
Goura ought to be separated. Chauna is practically a
pigeon in these characters, while the Limicolæ are not far
off. The Crypturi are gallinaceous.?
Pterylosis
As a general rule the feathers of birds are not distributed
uniformly over the surface of the body, but are set in the
skin in definite tracts, between which are spaces that are
entirely bare or covered only with down plumage. The
feathered tracts are termed pterylæ, the interspaces apteria. **
A few birds, such as the struthious, the penguins, and the
screamers, have an uninterrupted plumage ; but this state
of affairs, though corresponding with what one supposes
to be the original condition, is not necessarily so in the
birds under consideration. Thus, although the ostrich has
an uninterrupted plumage in the adult state, the young
embryo, as first figured by Miss Lindsay, has definite
pterylæ, thus proving that the continuous feathering is here
purely secondary. There is a very great variety in the
arrangement of the pterylæ among birds, and for the details
I DE MEIJERE has devoted some pains to the arrangement of the feathers
with reference to each other, a subject which, as he says, has been hitherto
treated of only in a stepmotherly fashion. It appears from his investigations
that the feathers are arranged in groups, as are the hairs of mammals. For
example, upon the naked region of the head of Nuinida the feathers are
grouped in fours, a stronger feather with two hair-like feathers, one on one side
and one on the other. This is what is generally found, a central stronger
feather with hair feathers surrounding it. There is here a remarkable analogy
with the grouping of mammalian hairs, where a stronger hair is often sur-
rounded by three or four more slender hairs. MOSELEY also in the case of the
dodo (q.v.) has found the feathers to be grouped in threes.
PTERYLOSIS
15
the reader is referred to the systematic part of this work.
In all, however, there are the following tracts present :-
(1) The spinal tract runs from the head to the oil gland.
This tract is sometimes continuous at the sides of the neck
with the ventral tract, to be described next. It is sometimes
a single solid tract throughout, but more usually there is a
space developed in it, an apterion in the back, which is of
greater or less extent. Commonly there is a break, more or
less distinct, between the anterior and the posterior portion
of the tract, which may be complete or may consist in an
abrupt transition between anterior stiffer feathers, and
posterior slighter feathers.
(2) The ventral tract is always a double tract, but the
median apterium may be very narrow. The anterior part
of the tract may be single, but sometimes it is double from
its very origin. Very commonly on the pectoral region
each half of the ventral tract gives off a lateral branch.
(3) The humeral tract is a band of stiff feathers running
across the humerus; it is always present and shows no parti-
cular modifications.
(4) The femoral tract is a corresponding band crossing
the thigh. There is sometimes, as in the barbets, a small
tract lying between the femoral and the spinal; and, besides
the main tracts, the patagium and the lower leg are more or
less covered with contour feathers. The study of Pterylo-
graphy was first taken up in a systematic manner by NITZSCH;
since his day the number of facts has largely increased, and
careful figures of the pterylosis of many birds, not figured
by NITZSCH, have been published by a host of observers,
especially GARROD, FORBES, SHUFELDT, PYECRAFT, GADOW,
and others. For references to these see the descriptions of
the different orders of birds.? . .
The general facts of pterylosis must be used cautiously.
See also W. MARSHALL, ' Pterologische Mittheilungen,' Zool. Gart. xiv. xv.
xvi.
2 For the musculature of the feathers see HELM, 'Ueber die Hautmuskeln
der Vögel,' &c., J. f. 0.1884, p. 321. These skin muscles are either limited to
the skin, running from feather to feather, or are parts of skeletal muscles, such
as the cutaneous branch of the latissimus dorsi, &c.
.
16
STRUCTURE AND CLASSIFICATION OF BIRDS
VU
On theoretical grounds it might fairly be assumed that a
continuous covering, without any distinctions between
pterylæ and apteria, was a primitive condition. But there
is evidence to show that where a continuous covering of
feathers exists it is not invariably a mark of ancient stock.
Thus the ostrich, as already remarked, which when adult
has practically no separation into pterylæ and apteria, has,
when young, very distinct pterylæ and apteria. In this
case, therefore, it is clear that the uninterrupted feathering
is a secondary character and not a primitive one. With the
penguins, on the other hand, it is conceivable that the
absence of apteria is a primitive character. As to the value of
the various arrangements of apteria in the pterylosis, GADOW
lays stress upon the continuous feathering of the neck, or
the presence there of lateral spaces, but admits that the
Indian painted snipe (Rhynchca) is an exception which
somewhat destroys the value derivable from the considera-
tion of the facts. FÜRBRINGER, on the other hand, uses in
his tables of characters the dorsal tract and its modifications.
But the variations which occur here in a single and surely
well-marked family (e.g. Picidæ) tend to shake our faith in
the value of the exact way in which the hypothetically con-
tinuous feathering has lost its continuity. No doubt GADOW
is right in saying that it is of taxonomic importance ' more
in the investigation of small than of large groups.'
NITZSCH, for instance, lays some stress upon the 'furcate
division and degradation of the portion of the spinal tract
situated between the shoulder blades' in the Accipitrinæ ;
this division includes the owls.
But on turning over his plates one is struck by the fact
that the peculiarity in question is by no means confined to
that group, occurring as it does in such widely removed
forms as Caprimulgidæ, Charadriidæ, and Psophia. Nor is
an undivided dorsal tract a distinctive mark of affinity,
since it is to be found in such a diversified assemblage as
that including Pavo, Alcedo, Certhia, Todus, and various
passerines. The ventral tracts divide each of them upon
the breast into an outer and an inner division in Pernis
PTERYLOSIS
17
apivora, Coracias garrulus, Rhamphastos, Musophaga, Gal-
lus, various cuckoos, Charadrius, &c. They do not divide
in Pandion, Cypselus, Cuculus, Opisthocomus, Buceros, Co-
lumba, Fulica, and Ciconia.
GARROD made originally the apparently reasonable sug-
gestion that the down feathers upon the apteria of many
birds may be the remains of contour feathers, from which
the inference is necessary that those birds with downs upon
the apteria are nearer to the continuously feathered and
ancestral bird than are those whose apteria are nude. But
the whole matter is rather more complicated than this.
There are birds with only contour feathers and nude apteria ;
there are birds with contour feathers only upon the pterylæ,
and down upon the apteria ; there are birds with downs
everywhere; and finally there are birds with downs only
upon the pterylæ, mixed with the contour feathers. The
facts, therefore, when stated thus fully are not so easy of
interpretation.
The evidence derivable froin Archæopteryx-less negative,
perhaps, than 'negative' evidence often is—may afford us a
clue. So many feathers of that bird are well preserved that
it seems possible that where feathers have not been preserved
they were either really absent or soft down feathers. The
latter suggestion seems to be the more probable, on account
of the plain fact that Archceopteryx was a flying bird. Now
the fact that the contour feathers are frequently preceded
by downs points in the same direction, viz. that the primitive
feathering of birds was in the form of downs. The persist-
ence of downs, therefore, on this hypothesis is so far a
primitive character, and the greater the persistence the more
primitive the bird. Thus those birds which have downs
everywhere will be the more archaic. This is so far promis-
ing that that group contains such apparently old types as
Palamedea, Opisthoconus, Rhinochetus, &c. On this view
the most modern of birds will be those which I elsewhere
try to show are an ancient race, i.e. the bulk of the Pico-
Passeres. But, as might be expected with an ancient race,
there is every variety shown, and members of this great
On
1/
18
group are found in all the divisions of birds founded upon
the distribution of the downs. This view throws a side
light upon the Struthiones. The feathers of those birds have
been called intermediate between contour feathers and
downs. It may be that they are primitive, and that the
struthious birds have arisen from some ancient type in
which the modern bird's feather had hardly been evolved.
Among nearly related families the details of pterylosis do at
least sometimes afford indications of resemblance. Thus,
for instance, there are certain small
likenesses between the barbets,
toucans, and woodpeckers (see
below), which help in establishing
the near kinship between the three.
families.
The size or the presence or
absence of the aftershaft appears to
be of little use for systematic pur-
poses. Among the ducks, for ex-
ample, some have it and some have
it not. It is as large as the main
feather in the emus and totally
absent in Rhea. Facts like these,

.
ER
T
Siem
17
74.
14
UTENTE
TE
Born
tates
A
411
Nhi
.
662
.
LV
*
.
.
.
..
S
.
..
22
WAT
KVIRIN
.
.
doubts upon the value of this
structure in classification. So too
FIG. 4.-FEATHER SHOWING
6 with the oil gland' and its feather-
AFTERSHAFT (AFTER SCLATER).
ing or absence of a tuft. Cancroma,
which in other points of its structure conforms to the heron
type, is alone in that group in having a nude oil gland. The
gland is absent in some parrots, present in others. GARROD
at one time thought that he could correlate among the
Pico-Passeres a nude oil gland with small cæca, and a tufted
oil gland with the absence of cæca ; to the vast majority
i A. PILLIET, 'Sur la Glande Sébacée des Oiseaux,' &c., Bull. Soc. Zool. Fr.
xiv. 1889, p. 115; R. KOSSMANN, ' Ueber Talgdrüsen der Vögel, Zeitschr. f.
wiss. 2001. 1871, p. 568.
PTERYLOSIS
19
apply. But the todies were found to be birds with a tufted
oil gland and with large cæca.
It has been pointed out that when the oil gland has a
tuft of feathers upon its apex the rest of the gland is un-
feathered, and that, on the contrary, when the tip is nude
the general surface of the gland is feathered. The oil gland
is, so far as we know, a structure special to birds ; it is, indeed,
the only purely external glandular apparatus that exists in
them. It is therefore possible, if not probable, that the
organ first arose in the class—that it is not an inheritance
from any ancestor. On this view it is quite possible that
the absence of the oil gland may not be always due to its
disappearance; birds without oil glands may or may not
have lost them. It seems very likely, for example, that the
usual absence of this structure among the struthious birds
is rather a primitive than a secondary character. If this
view of the matter is justifiable, the presence of a tuft may
also be, in some cases at least, secondary; for it is certainly
a specialisation that may have appeared after the oil gland
was fully developed. .
Alimentary Canal
The tongue l of birds is one of the most variable organs
as to size and texture. In Plotus, for example, it is
practically altogether absent (see fig. 5). When present it
is larger or smaller, more or less fleshy. The long, thin,
horny tongue of the toucans characterises those birds; the
parrots (see fig. 6) have a thick and fleshy tongue; naturally
the organ is of more use to the latter than to the former.
A very remarkable modification of the tongue, seen in birds
quite remote in the scale, is the pulling out of the free end
into a tuft of fine fibres ; this is associated with the capture
of honey or ininute insects from the corollas of flowers; it is
I C. S. MINOT, 'Studies on the Tongue of Reptiles and Birds,' Ann. Mem.
Boston Soc. Nat. Hist. 1880; NITZSCH-GIEBEL, 'Die Zunge der Vögel;'&c.,
Zeitschi. f. d. ges. Naturw. xi. 1858, p. 19; LUDWIG, PRINZ V. BAYERN, Zur
Anatomie der Zunge (München, 1884). .
20
STRUCTURE AND CLASSIFICATION OF BIRDS
UTCH!
BA
?
ASE
.
.
..
T
seen in the Trichoglossinæ (see fig. 6), named so on account
of the very structure, and in the Nectariniidæ, &c. Very
frequently the tongue is more or less spiny upon its surface,
particularly towards the attached end
of the organ. A very singular modi-
fication is the extraordinarily long
tongue of the woodpeckers, which
is, of course, associated with the ex-
traction of grubs from the crevices in
trees. A detailed description of the
4 t
numerous forms of this organ would
occupy more space than can be allowed;
but the principal varieties will be
found described under the different
families. The modifications of the
tongue are not of great assistance to

NI
Fins
2
AN
.
.
?
...
YOU
VI!
- -
Ti
..
10+
WIDZINZ22.
1
-
.
4
SY
.
.
I
n
11
IUF
innannnnnnnnnn
10.RCZYTATTI
A
Inila
.
2
ORAN
Not
.
73
WE
.
IRI
M
win
Settu itu
Act
Willi-
SIS
.
.
ad
a
WW
1
..
V
V
egamannauukot c....
S
UNIT
.
LA
INS
2
.
TA
VO
2014
www
V
//
/
2
22
.
ww
IR
UUTIS
VA
Nr.
TY
.
V
LAM
T
NU
TOP
.
.
Um
NO
TA
Au
22
KWA
IN
2
Fig. 5.- A, LOWER MANDI-
BLE OF INDIAN DARTER.
t; RUDIMENTARY TONGUE.
B, TONGUE IN PROFILE.
FIG. 6.-HEAD OF Lorius, SHOWING EXTENDED TONGUE
WITH BRUSH TIP (AFTER GARROD).
the taxonomist, except as regards smaller groups. Thus
the Plataleidæ have been distinguished from other Herodiones
as · Lipoglossæ.
Teeth are not met with in living birds. RÖSE, however,
has discovered what he believes to be a rudimentary tooth
band ( Zahnleiste ') in Sterna,' a discovery which may have
1 This has been recently confirmed by Miss CARLSSON (' Ueber die Schmelz-
leiste bei Sterira hirundo,' Anat. Anz xii. 72), who found it to characterise both
jaws. For other embryonic traces of teeth see P. FRAISSE, · Uber Zähne ut. Zahn-
ALIMENTARY CANAL
21:
some added significance in view of the possible relationship
to modern birds of the cretaceous Ichthyornis (cf. below).
The need for teeth seems to have disappeared with the
development of a horny bill, the replacement of the one
structure by the other being, perhaps, comparable to the
replacement of functional teeth by horny plates in the.
Ornithorhynchus. Functional teeth, however, existed in
the Jurassic Archæopteryx and Laopteryx (?), and in the
Ichthyornis. In the latter the teeth are in sockets, in the
former in grooves. In both the teeth are numerous, but
not, perhaps, extending on to the premaxillaries; the teeth
show no specialisation in different regions; they are of
dentine coated with enamel, and in Hesperornis the basal
portion of the roots consists of osteodentine.
The Eocene bird (from the London clay) Odontopteryx
toliapicus has a strongly serrated upper jaw, a state of
affairs which is paralleled in the South American passerine
Phytotoma rara. In this latter bird, as Parker has pointed
VII
the dentary and palatine ridges of the premaxillary.' He
suggests that in these birds and in the merganser, where
similar denticles' occur, the bone of the jaw has grown
into arrested dental papillæ.
The esophagus dilates in a few birds into a crop, which
is more highly specialised in Opisthocomus (q.v.) than in any
other form. When the crop is well marked it consists of a
spherical to oval dilatation of the cesophagus, which in
pigeons is divisible into a right and left half and an inter-
mediate unpaired portion. The gallinaceous birds, the
parrots, and among the Limicolæ the American genera
Thinocorys and Attagis, are provided with a crop. In other
birds a slight dilatation of the cesophagus, either permanent
papillen bei Vögeln,' J.B. nat. Ges. Leipzig, 1882, p. 16; A. F. J. C. MAYER,
• Zähne im Oberschnabel bei Vögeln,' &c., Froriep’s Notiz. xx. 1841, p. 69 ;.
BLANCHARD, 'Observations sur le Système Dentaire chez les Oiseaux,' Comptes
Zool. Zoot. Inst. Wiirab. v. 1879.
| In his memoir upon ægithognathous birds.
22
STRUCTURE AND CLASSIFICATION OF BIRDS
7
O
or temporary, foreshadows the fully developed crop of the
birds mentioned.
The stomach 1 consists of two compartments following
each other, the glandular proventriculus and the more mus-
cular gizzard. The proportions of these two segments of
the stomach vary, and both are much reduced in the
hoatzin, whose crop appears to take on the function of a
gizzard. The proventriculus is usually, but not always,
separated by a marked constriction from the gizzard, and has
a patch of large glands which generally forms a band lining
the upper part of the sac and continuous right round it; to
a proventriculus in which the glandular patch is disposed in
this fashion the term 'zonary' is applied. More rarely the
patch of glands is a single oval or round patch not continu-
ous round the proventriculus, or there may be two such
patches. In Plotus anhinga the two patches of proven-
tricular glands are contained in a special diverticulum
of the proventriculus. In Tantalus ibis MITCHELL ? has
described a remarkable divergence from the usual structure
of the proventriculus. In this bird the glandular areas are
two, as in other storks. Above these is a row of crypts,
which are partly glandular and partly lymphatic, and are
believed to be organs for the absorption of water. Among
the Steganopodes and in other birds the proventriculus is
much larger than the gizzard, which follows. In certain
tanagers this state of affairs culminates in the apparent
absence of the gizzard as a distinct structure (see below).
LUND and FORBES have mentioned a number of tanagers in
which this occurs. The gizzard is more muscular in grain-
eating and in some other birds than it is in flesh- and fish-
eating birds. It is strong and hard and lenticular in form in
the Galli, Ralli, &c., bag-like and soft-walled in the heron,
&c. The lining of the gizzard undergoes a remarkable
modification in certain pigeons (9.v.), where it may be even
ossified. ..
? On the Proventricular Crypts of Pseudotantalus ibis,'P. Z. S. 1895, p. 271.
? A comprehensive work upon this organ is that of CAZIN, Ann. Sci. Nat.(7),
iv. 1887, p. 177. See also the same, Structure et Mécanisme du Gésier dès
Oiseaux,' Bull. Soc. Philom. 1888, p. 19.
ALIMENTARY CANAL
The intestine of birds varies much in proportional as well
as (naturally) in actual length. In the systematic part of
this work a number of actual measurements will be found;
from these it is obvious that on the whole purely frugivorous
birds have a short gut, while fish- and grain-eating birds have
a long gut. To compare, for example, two birds of roughly
the same size but of different feeding habits, the touraco
and the common pigeon, we find in the former a gut of
42 c.m., and in the latter of 108-132 c.m. As the gut is
always longer than the abdominal cavity in which it lies, it
has to be thrown into folds in order to find room.
In the embryo chick the gut is straight and is supported
by a continuous dorsal mesentery of equal vertical diameter
throughout. The coiling is both lateral, which results in
lateral foldings of the mesentery, and vertical, which results
in unequal growths of the mesentery. It only affects the
middle part of the alimentary tract, the oesophagus and
stomach on the one hand, and the rectum on the other, or
at least a part of it, retaining the original straight condition.
The lateral foldings give rise to secondary connections
between different regions of the mesentery, and tend to
obscure the course of the gut; but it is easy, by carefully
removing the entire intestine to distinguish these secondary
mesenteries from the primary sheet binding the gut to the
dorsal body wall.
When the body walls of a series of birds are removed, and
the disposition of the intestines thus shown examined, they
have been found to present great differences. These have
been studied and described by Gadow in two memoirs,' and
the main results extracted for the account of the digestive.
system in Newton's · Dictionary of Birds. It is mainly
from the latter work that the abstract here given is drawn.
In a goose, for example, the main disposition of the
intestinal folds is in a longitudinal direction ; they run
parallel with each other in a direction roughly coinciding
1. Versuch einer vergleichenden Anatomie des Verdauungssystemes der
Vögel,' Jen. Zeitschr. xiii. 1879, pp. 92, 339; On the Taxonomic Value of the
Intestinal Convolutions in Birds,' P. Z. S. 1889, p. 303.
24
STRUCTURE AND CLASSIFICATION OF BIRDS
with the long axis of the body. On the other hand the
intestines of a gull, seen when the body wall is cut through
and without any other disturbance, have a watchspring-like
arrangement. In Platalea the coils are parallel, but mainly
at right angles to the long axis of the body.
These and other variations have been mapped out by
GADOW into seven principal schemes, which are represented



-----
----
-
-
-
-
-
I
II
IV



-
f
V
Fig. 7.-INTESTINAL LOOPS (AFTER GADow).
a, isocoelous ; b, anticolous; C, anti pericolous; d, isopericolous; e, cyclocælous;
f,g, plagiocælous; , telogyrous ; P, pylorus.
N.B.—The ascending branches are dotted.
in the annexed cuts. These are, of course, not accurate
pictures of the actual course of the gut, but diagrams' of the
principal relative positions of the intestinal loops ; and it
must be further explained, in relation to another mode of
mapping the intestine that we shall refer to immediately,
that the diagrams, mainly if not entirely, concern the lateral
foldings of the mesentery that have been already mentioned;
they are representations, in fact, of the relations of the
folding of the gut to the body cavity and not to the medial
line of attachment of the mesentery; nor is any attention
ALIMENTARY CANAL
paid to fixed points in the intestine, such as the cæca or the
vitelline duct. They express, however, an interesting series
of facts. The general term of orthocoelous is applied to
those cases where the folds are as a rule parallel to each
other and in the long axis of the body. When they form
spirals the general term of cyclocoelous is applied to them
by GADOW.
The prevailing number of loops is four, of which the first,
the duodenal (which contains the pancreas), is a loop which
rarely undergoes additional twisting. The orthocoelous con-
dition may be regarded as the starting point. The cyclo-
coelous arrangement, as will be seen by the figure, is derived
from the orthocoelous by the conversion into one spiral' of
the second and third loops. In all the Passeres the cyclo-
colous arrangement is arrived at by a spiral twisting of the
middle or second loop only (there being but three loops) ;
this kind of gut has been termed by GADOW mesogyrous.
The Limicolæ, which have a spiral formed by the second and
third loops, are also, of course, mesogyrous; but it is clear that
a similar state of affairs has been arrived at independently.
Finally, there is the telogyrous condition, in which merely the
end of a given loop or loops becomes twisted into a spiral,
the rest remaining straight. This is shown in the last of
the series of figures on p. 24. In such cases, as in the one
figured, the duodenal loop rarely, but still occasionally, under-
goes a twisting. The plagiocoelous condition is an irregular
twisting of the ends or of parts of the loops of an orthocoelous
gut. These varied arrangements of the gut may be recog-
nised in most birds; but there are a few exceptions of which
note must be taken. In certain fruit-eating birds, such as
Carpophaga, Rhamphastos, the gut is so short and wide that
the number of loops is reduced, and the arrangement quite
undecipherable. On the other hand the extremely lengthened
gut of the fish-eating Pandion produces an equal confusion.
Since GADOW's description of the coils of the intestinal
canal in birds the subject has been studied from another point
of view by CHALMERS MITCHELL. GADOW considers only
1 'On the Intestinal Tract of Birds,' P. 2. S. 1896, p. 136.
2
26
STRUCTURE AND CLASSIFICATION OF BIRDS
the way in which the folds of the gut are packed away in the
body cavity. MITCHELL describes the actual coiling of the gut
itself. In its simplest condition the gut of any animal, as is
shown in their embryos, is a straight tube, passing from the
stomach to the cloaca, supported by a continuous dorsal mesen-
tery, the ventral mesentery being in nearly all vertebrates
defective so far as the intes-
tinal region is concerned.
This simple condition is,
however, not retained in any
existing bird ; in all the length
of the tube is to some extent,
generally to a large extent,
longer than the body. The
alligator (fig. 8) offers the
ideally simplest condition of
a coiled intestine, where ad-
ditional length is achieved
without any complications
of the gut, merely by its
Fig. 8.-Alligator Mississipiensis ; being
is being thrown into a series of
to
ALIMENTARY TRACT (AFTER CHALMERS folds, of which all are more
MITCHELL).
or less alike. So simple a
condition as this does not occur in any known bird. But
there is more than one type in which this arrangement is
retained with but little modification. It is a significant fact
that the most primitive arrangement of the folds of the
intestine, judged from the crocodilian standpoint, than which
we have none other more nearly approximating to the
probable reptilian ancestor of birds, is found in birds which
other considerations lead us to assign a low position in the
avian series. In the accompanying drawing (fig. 9) of the
screamer, for example, we have a gut which is but slightly
advanced from that of the crocodile. The greater part of
the small intestine shows the same series of undifferentiated
folds, only the duodenal loop (not missing as a specialised
fold in any bird) being separated off from the general coiling.
The large intestine, however, differs from the short and

0
ALIMENTARY CANAL
27
straight large intestine of the crocodile by its convoluted
course. So too with the gallinaceous bird (fig. 10), where

P.V.
|
annet
l.i.
POM
ac' noc dcl.
FIG. 9.-Chauna chavaria ; ALIMENTARY TRACT.
s, proventriculus; I, glandular tract; il, duodenal loop; 2-1, large loop of small
intestine; y, vitelline luct; C, cæca ; 7.i, large intestine ; pov, portal vein ; 7.0,
rectal vein. (After CHALMERS MITCHELL.)

S
.
Fig. 10.- Argus giganteus, CHICK ; INTESTINAL LOOPS
(AFTER CHALMERS MITCHELL).
28
STRUCTURE AND CLASSIFICATION OF BIRDS
ia....ni.iiiiii
the duodenal loop is again the only specialised region of the
intestine.
The ostrich and the cassowary present but little modifi-
cation of the same
primitive type of gut.
In the former we have
a rather more com-
plicated duodenal loop,
which is furnished with
a small subsidiary fold.
Then, too, the large in-
testine has the same
remarkable folded con-
dition seen, but to a
less extent, in Chauna.
Fig. 11.-Casuarius ; INTESTINAL TRACT Casuarius is simpler
(AFTER CHALMERS MITCHELL).
than Struthio. In all
these figures (taken
from Mr. MITCHELL'S
paper) the course of
the principal blood
vessels is shown ; only
the veins, as the arteries
were found invariably
to accompany the veins.
It will be observed that
the principal feeder of
the portal vein runs
directly across the main
mesenteric fold, and
ends near to the vitel-
line duct, the rudiment
of the yolk sac; from
Fig. 12.- Struthio camelus; INTESTINAL
TRACT.
the junction of this
*, short-circuiting vessel cut across. (After with the main stem of
the. mesenteric vein
arise two other vessels; one of these supplies the duodenal
loop, the other the large intestine; there is sometimes a


.
.
.
1
-Line-é.
is
CHALMERS MITCHELL.)
ALIMENTARY CANAL
"short-circuiting' connection, as MITCHELL terms it,
between the duodenal and the main mesenteric stem.

Uli
De
Fig. 13.-Haliaetus albicilla ; INTSETINAL TRACT.
x as in fig. 12. (After CIIALMERS MITCHELL.)

1.
Y
2
.
LAI
.0
.1::......:
th .
Fig. 14.--Ara ararauna; INTESTINAL TRACT.
t, as in fig. 12. (After CHALMERS MITCHELL.)
In other groups of birds this simple state of affairs is further
evolved, but in some there are remains of the primitive
30
STRUCTURE AND CLASSIFICATION OF BIRDS
folded intestine for a greater or less extent; thus in the
penguin a good deal of the intestine retains the early
system of folding. But this bird is remarkable for the
extraordinary complications of the duodenal loop, which has
become enormously lengthened, and, in Eudyptes, thrown
into a series of secondary loops, which in Aptenodytes
are arranged in a spiral—a convergent resemblance, thinks
MITCHELL, to Haliaetus (see above, fig. 13). Platalea,
which, possessing as it does the complete muscle formula of
the leg, must be regarded as a primitive type among the
storks, has the greater part of the small intestine disposed
in the primitive fashion; the duodenal loop is, of course,
distinct, and there is also a well-marked long loop just
before the large intestine. Haliaetus albicilla, to which
reference has just been made, is less divergent from the
primitive form than many other birds, and Larus marinus
has preserved considerable traces of the same. Among the
most specialised birds from the present point of view are
the parrots (see fig. 14).
In Ara, at any rate, there is nothing left of the original
primitive folds of the intestine; the whole of its course is
disposed into six specialised loops. The owls and the Capri-
mulgidæ appear, according to MITCHELL, to have preserved
much of the primitive short, convoluted loops of the lower
birds, and so, though to a less extent, has Corythaix. The
very short intestine of the Passeres, represented here by Parus
major, is not so easy to understand, but its general appearance
is that of a primitive gut. Some further details will be found
in the succeeding chapters, under the different families to
which they refer.
The cæca lie at the commencement of the large intes-
tine, which indeed can be, as a rule, only differentiated from
the small intestine by the break thus caused. This is, how-
ever, not invariably the case, for in Struthio (see fig. 12, p. 28)
there is a distinct break between the two sections of the
gut, quite independent of the cæca, which can be readily
seen from an inspection of the figure cited. The cæca are
among the most variable organs of birds. Not only are they
...
.
ALIMENTARY LA RY
CANAL
sometimes completely absent, as in the majority of that
large assemblage of birds the picarians, but when present
they show every degree of relative size. In the Passeres, and
in some other birds, the two cæca are the merest nipples,
which cannot be believed to serve any function. They are
in the same way reduced in size
in the hawks and storks. On the
other hand, in the gallinaceous
birds, in the Limicolæ, and in some
others the cæca are large tubular
diverticula of the gut, the length
being sometimes to be measured
by inches. Among the owls the
cæca are large, and have the Fig. 15.--Parus major.

; :
;
YYY
2, as in fig. 12. (After
CHALMERS MITCHELL.)
(D
swollen at the blind extremity.
The cæca are most complicated in the ostrich, the screamers,
and the tinamou Calodromas, under the descriptions of which
birds will be found an account of this organ. The herons
are remarkable for the fact that one of the two cæca has
disappeared, the remaining one being but small.
The liver is invariably composed of two lobes, of which
the left often shows a more or less distinctly marked
secondary division. The size of the lobes varies greatly, as
does their relative size. Thus in some birds the liver lobes
are quite hidden by the sternum; in others again they
descend some way down below the shelter of that bone and
are apparent when the muscular walls of the abdomen are
cut through or removed. The two lobes are occasionally
equal or subequal in size; more generally there is a dis-
crepancy, the right or left, as the case may be, being the
larger, sometimes very much the larger. The two lobes, of
the liver are commonly firmly attached to each other by a
bridge of hepatic tissue. In Chauna they are nearly separate,
being only united by a very narrow isthmus of liver substance.
The liver sometimes (e.g.in Rhynchotus rufescens) has two or
Yni2
LLU
its substance at the free edge, a state of affairs which has a
32
STRUCTURE AND CLASSIFICATION OF BIRDS
very lizard-like appearance. The relative sizes of the
liver lobes appear to be of no importance systematically.

1
UN
ACAO
127
.
.
-
1
*
.
...
NE
Blume
..
.
+
!
/
:
.
.
W
III
ZIVO
TITA
JUDIT
.
VO
. .
...
Hill
TO
.
M
V
..
.
..
.
.
1
ZZI
NYI
.
.
.
.
.
1
DEIN
1
T
I
.
.
787UII
ID
: 4 ..
As..
. .
..
Hi
1
.
27
.
Juan
ANN.
MAISH
22.
.
.
CZ
W
.
...
09111
2
VTT
.
.
V !
V1
277272
M
.
.
5
A
.
.
..
.
.
-
JUILD
N
.
.
.
..
.
.
S
HA
.
11.
'
.
1
2
till
.
.
.
.
.
**
E
w
*
TI
.
VWmn
.
.
.
.
.
.
.
.
NU
D
.:
IS
.
111
S
-
.
.
.
IN
HINTAY
.
Ahli
/
/
VID
WIND
WWWLALU
WIWINNINNI
//
WI
//
SI
*
.
2
F
VIVA
..
X2
.
M
TIIS
OM
ter
C
..
..
.
.
PER
-
.
.
W
a
.
.
ter
.
S
7.c.
A
N
.
.
1
.
'
YNADI
.
N
.
!
N
NA
---
A
.
.
N
IN
1
.
.
..
.
NE
.
M
WN
.
.
ZN
CA
>
M
M
NA
IN
IC
N
F
TA
AAN
.
.
.
UTE
VIII
VII
.
W
..
2
..
NINI
. .
..
HT
M
OS
.
..
O
R
..
..
...
. ..
.
. .
.....
.
..
N
.
WITZ
YO
7
.
VII
..
.
.
ht
.
M
.
WAS
hr..
M
.
1
All
M
TITI
NE
M
hom
.
NU
..
*****
TUIN
-
M
NA
M
M
.
hr
M2
M
M2
V
ILIN
SI
WW
a
V
1
VI
AM
A
AM
W
UUNIMNINTIMININNIIIIIIIIIIMIITINIMO
MIINIINIUINITIVUMINIIIIIIIIIIIINNNN!
MINIT
DMMMMMM
This
WWW
.
HT
WWW
TUT
III
INI
FIG. 16.- ALIMENTARY VISCERA OF INDIAN DARTER.
G.B., gall bladder ; h.d., c.d., bile ducts; P, pancreas.
Numerous livers are figured by GADOW in Bronn's Thier-
reich.
ALIMENTARY CANAL
38
. The gall bladder is an organ which is not invariably
present in birds. It is even sometimes present and some-
times absent in the same family (e.g. parrots). As a rule
this vessel is of a rounded or oval contour and is embedded
on the surface of the right lobe of the liver. The Picidæ,
Capitonidæ, and Rhamphastidæ are remarkable for the
extraordinarily elongated gall bladder, which reaches a long
way down the abdominal cavity; this is described more
fully below. The penguin has an almost equally elongated


d. h.
luklar
2.c
2
.
.
..
d.az
Illy
.
1
Gur
.
.
.
.
A
...
.
.....
A
S
.
..
***
.DO
.
the
V
.
.
.
.
.
.
.
Sin
.
.
.
...
..
.
.
.
.
...
So
UV
.
V
..
FIG. 17.—DUODENUM OF Syrrhaptes.
v.f, gall bladder; d.c, cystic duct; d.N,
hepatic duct; d.pl, d. p2, pancreatic
ducts. (After BRANDT.)
Fig. 18.—DUODENUM, BILE DUCTS, AND
PANCREATIC DUCTS OF ANOTHER Syr-
rohaptes (AFTER BRANDT).
gall bladder. The position of the apertures of the cystic
and hepatic ducts upon the small intestine varies. The
ostrich is remarkable for the fact that the single duct opens
practically into the stomach.
· The pancreas lies in the fold of mesentery that unites.
the two arms of the duodenal loop. It is commonly more or
less distinctly composed of two parts, and in relation to this
there are two pancreatic ducts which pour its contents into
the duodenum. Apparently, however, no value can be
34
STRUCTURE AND CLASSIFICATION OF BIRDS
attached to either the form of the gland or the number and
position of the orifices of its ducts. In Syrrhaptes para-
docus, for instance, both of the arrangements figured in the
accompanying cuts have been found by BRANDT, who inves-
tigated the structure of the bird. In one of them both
ducts open close to each other and to the cystic duct on the
ascending part of the duodenal loop; in the other the cystic
and hepatic ducts were on opposite sides of the duodenal
loop, and in common with each opened a single pancreatic


Aisa
.
:
.
Juc.c.-
.
mungen
ce-
*
.
'
Fig. 19.DUODENAL LOOPS OF FIG. 20.--DUODENAL
Rhec americana.
LOOP OF Rh. Darwini.
hc.e, he, bile ducts; pl, p2, pancreatic ce, he, bile ducts; p1, p2, pan-
ducts. (After GADOW.)
creatic ducts. (After GADOW.)
duct. This latter arrangement was found by GADOW in
Pterocles. In two species of Rhea the relative positions of
the pancreatic and bile ducts were as is shown in the figures.
In the owl Photodilus badius I found that the cystic duct
opened near to the summit of the ascending arm of the
duodenal loop; below this opened the hepatic duct, and
some way below this again, and near together, the two pan-
creatic ducts. A good many details upon this subject will
be found in GADOW’s paper on the digestive organs of birds.
The cloaca of birds is the terminal chamber of the
alimentary canal, which also receives the urinary and genital
ducts, and is provided with an appendix of unknown function,
ALIMENTARY CANAL
35
the so-called bursa Fabricii. GADOW, in a recent work ? upon
this region of the alimentary canal, recognises three cham-
bers in the cloaca. Above, and separated by a constriction
from it, is the coprodæum, into which the rectum opens;
this is divided by a constriction from the middle chamber,
or urodæum, which receives the genital and urinary ducts;

-
-
--01
-
-
-
.
www
IV
.
Ne
www
BE
ww
SHEMA 27202
...
POV
ZON
2
PAIS
..
-
-
IN
boy
.
TA
WR
NE
CICO
BE222
SES
re
---
-
---------
-
11
..
LIVE
2.
Tii
U
RE
IT..tv
Y
.
Fig. 21.-CLOACA Or Chauna derbianu LAID OPEN FROM IN FRONT.
al, rectum; 0, orifices of ureters ; U', genital papillæ ; c, fold separating coprodæum from
uroclæum ; d, fold separating wrodæum from proctodauin ; l, opening of f, bursa
Fabricii. (After FORBES.)
then follows the proctodæum, of which the bursa Fabricii
is a diverticulum.
The bursa Fabricii has been chiefly investigated by
FORBES 2 and WENCKEBACH. It is a dorsal diverticulum of
the proctodæum, and therefore has nothing to do with the
Remarks on the Cloaca and on the Copulatory Organs of the Amniota,'
Phil. Trans. vol. clxxvii. p. 5.
2 'On the Bursa Fabricii in Birds,' P. Z. S. 1877, p. 304.
3 'De Ontwikkeling en de Bouw der Bursa Fabricii,' Inaug. Diss. Leyden
1888. See also E. RETTERET, · Contribution à l'Etude du Cloaque,' &c., J. de
l'Anat. xxi. 1885, p. 369.
D 2
36
STRUCTURE AND CLASSIFICATION OF BIRDS
ventral bladder of other vertebrates. It is largest in young
birds, and often becomes obliterated in older birds. The
general relations of the bursa to the cloaca are shown in
the two accompanying figures. The organ contains a
quantity of lymphatic follicles, and presents us with two
types. In most birds it is a diverticulum opening by a
narrow neck into the proctodæum ; but in the struthious
birds (in the young at any rate) it is not constricted at its
orifice into the proctodæum, and the boundaries of the two
are therefore indistinct. The structure and arrangement of


R
S.
.
.
SSS
B
B
ar'..
в
C
00
D
GES
'Fig. 22.-Two TYPES OF BURSA.
R, coprodæum ; C, urodæum ; D, proctodæum ; B, bursa ; d, ureters. (After FORBES.)
the follicles and of the bursa generally have led WENCKEMANN
to certain classificatory conclusions.
Reproductive and Renal Organs
The kidneys are so unimportant from the point of view
of the present book that they can be dismissed in a few
words. Each kidney is a lobulated organ lying in the pelvic
region, so closely in contact with the adjacent bones that
they are marked by grooves upon the dorsal surface. In
some hornbills each kidney is divided into an anterior and
a posterior piece, which are perfectly separated. A ureter
runs from each kidney to the urodæum..
The reproductive organs consist of a pair of testes in the
male, and of one, rarely two, ovaries in the female. Corre-
sponding to the single ovary (the left) is a single oviduct,
the right one remaining rudimentary. BALLOWITZ 1 has
1. Untersuchungen über die Struktur der Spermatozoen,' &c., Arch. Mikr.
Anat, xxxii. 402.
CU
REPRODUCTIVE AND RENAL ORGANS
37
figured the spermatozoa of many birds, whence it appears that
their form is often characteristic, and may be of systematic
use. A penis is not present in all birds ; it exists in the
Struthiones, the Anseres, Tinami, Herodiones, Galli, and
Edicnenus. It is a paired organ--that is to say, it is
composed of two incompletely joined halves with a longi-
tudinal groove.
The Colom
Birds differ both from reptiles and mammals in the com-
plication of the subdivisions of their body cavity. The
subject is one that is far from being thoroughly worked out,
but enough information has been collected to allow of a
certain amount of definite statement and of comparison
with other animals.
When a bird is dissected in the usual way from the
ventral surface, the abdominal cavity, or at least the cavity
containing what are generally termed the abdominal viscera-
i.e. liver, intestines, &c.—is seen to be divided into two by a
toughish septum, which varies in extent according to the
bird dissected. This membrane, to which attention has
ploon,' has been investigated in a number of birds by me.?
Its relations in the common fowl have been described with
the aid of diagrammatic representations of sections by
BUTLER.3
. This membrane, believed by MALL 4 to be the actual
homologue of the omentum of the mammal, is more or less
horizontal in direction, so that it may be conveniently
termed, without prejudice to its homologies, the ' horizontal
septum.' This horizontal septum is attached to the ventral
body wall, to the oblique septa (of which see description
later), and to the gizzard, which viscus appears to lie within
* In his memoir upon the anatomy of the storks and flamingo in P. 2. S.
.1883, p. 638.
2 Notes on the Visceral Anatomy of Birds,' P. Z. S. 1885, p. 836.
3. On the Subdivision of the Body Cavity in Lizards, Crocodiles, and Birds,'
P.Z. S. 1889, p. 452.
Journ. Morph. 1891.
38
STRUCTURE AND CLASSIFICATION OF BIRDS
the thick septum, in a cavity formed by the splitting of its
layers. Anteriorly the horizontal septum, passing forwards,
lies beneath the liver, coming into relations on each side
with a cavity which will be referred to later as the 'pulmo-
hepatic recess.'
If, therefore, the abdominal walls of the bird have been
cut through anteriorly to the attachment of the horizontal
septum to the abdominal walls, the only abdominal viscera
exposed will be the gizzard and the liver lobes. These
latter are separated from each other by the median vertical
falciform ligament,' which is continued backwards to divide
the cavity into right and left halves.
If, on the other hand, the abdominal walls of the bird
have been cut through posteriorly to the attachment of the
horizontal septum to the abdominal walls, the viscera
exposed will be the intestines and kidneys and not the
liver.
In some birds—for instance, in the duck, and in many
charadriiform birds—the horizontal septum is so short
behind the gizzard that the latter is closely attached to the
abdominal parietes by what looks at first sight almost like a
pathological adhesion, due to peritonitis. On the other
hand in many storks, in Chauna, Cariama, struthious and
other birds, the horizontal septum is very extensive, reaching
back to the immediate neighbourhood of the cloaca. Various
intermediate stages are offered by other birds.
The Oblique Septa.—Reference has been already made to
these structures, which are present in all birds, and concerning
whose homologies there is some divergence of opinion. Their
structure and relations are as follows: On either side of the
body is a tough fibrous sheet of membrane, which runs an
oblique course (hence HUXLEY'S nameof oblique septum'),
entirely enclosing and shutting off from the abdominal cavities
(dorsal and ventral) the lungs and air sacs, with an excep-
tion to be noted immediately. These oblique septa have,
as HUXLEY pointed out, a tent-like arrangement, coming
into contact with the median septum in front of the heart,
1.On the Respiratory Organs of Apteryx,' P. Z. S. 1882, p. 560.
THE CELOM
39
thenice diverging to be attached ventrally to the sternum
along two lines, one on each side, set obliquely to the median

C.cl
In.
A
.
Y
+
++
VT
.
.
.
.
.
.
ta
A
.
+
+
-
.
.
-
-
.
.
.
1
.
-
2
1
.
.
.
.
I
I
IIIA
.
_
I
+
23 - :
ERSAL
IT
NE
TEEL
CALOR
ASSIETTEKNE
A
FTER
V
20
WWW
A
2
SEL
E
.**
G
-
t
.
.
V.CO
.
.
U
-
ROWE
A
.
.HH
.
.
*
.
4
.
.
*
...
-
.
.
.
.
HI
.
-
WS
.
.
.
**
1
be
"
11
.
...
1
.
.
A
.
.
.
.
..
.
112
.
17
1
.
.
SY
14+
e-
/
Mulk
VIL
-
-
-
SESSIE
-
UNI
ì via.l.
FIG. 23.-RESPIRATORY ORGANS OF DUCK.
I-V, air sacs; Tr, trachea; 1.1, dorsal margin ; v.a.l, ventral margin of lungs; 1-3, dissepiments
between air sacs; so, aorta; c.a, cæliac artery ; m.li, mesenteric ; m, muscular fibres on 0.s,
oblique septum ; V.S, vertical median septum ; L.c, longus colli: K, kidney. (After HUXLEY.)

...
Ао
di
CA
CA
I
d.l. /
S
.
..
S.
.
.
.
.
.
.
women
.
WW
.
.
eya
.
SAU
.
.
.
.
.
.
.
.
.
1-
.
.
.
ELULARES
72.
C
22
.
WATT
www
.
*
.
*
ww
.
.
WS:
.
TUL
..
IN440
.
.
w
P
.
*
.
1.
.
.
ATS
*
my
.
pa
11
W
.
U
W
A
SO
Luvina
.
lt
Z
ZA
.
BWA
70
.'"
-
amame
F
0.S.
T
1.
.
i
v
.cl.l. II
2
717
FIG. 24.-RESPIRATORY ORGANS OF APTERYX. LETTERING AS IN FIG: 23
(AFTER HUXLEY
40
STRUCTURE AND CLASSIFICATION OF BIRDS
attachment of the falciform ligament. Dorsally they are
attached to the parietes. As a general rule the abdominal
air sac is the only one of the posterior air sacs (see fig. 23)
which is not enclosed within the oblique septa; in all birds,
so far as is known, except the Apteryx, the wall of this air
sac ‘has been apparently driven out, like a hernial sac,
between the peritoneum and the parietes, and projects into
the abdominal cavity. In Apteryx the air sac in question
is completely enclosed by the oblique septum. Another
exception to the statement made above as to the completely

w
F
Mini
w
US
" free Fold, OBLIQUETTEN OF EE
Fig. 25.-DIAGRAMMATIC TRANSVERSE SECTION OF EMU, TO SHOW THE PRO-
JECTION OF OBLIQUE SEPTUM.
a, as a free fold ; 0, falciform ligament.
dissepimental nature of the oblique septa occurs in a few
birds (e.g. emu and Cariama), in which the posterior end
of the oblique septum, though firmly attached to the dorso-
lateral parietes, is not so attached ventrally, but projects
into the abdominal cavity as a free fold. In these cases the
free fold is double (see fig. 25), the inner half being conti-
nuous with the horizontal septum. To the possible signi-
ficance of this fact we propose to return later.
The oblique septa are, as has already been stated, mem-
branous, but they are occasionally and partially invaded or
covered by muscular tissue. HUXLEY speaks of “unstriped
THE CELOM
muscular fibres' in the oblique septum of the duck ; and in
the puffin? (Fratercula arctica) and the penguin (Eudyptes,
Eudyptula minor and Spheniscus demersus) the posterior

Set.
17
ALEVITITO
A.S
izs
FIG. 26.--DIAGRAM OF A TRANSVERSE SECTION THROUGH
THORAX OF DUCK.
L.L, R.L, lobes of liver ; L, lungs; A.S, horizontal septum; O.S, oblique septum.

21
IIIIII
IIIIIIIII
111
JE
III
FIG. 27.-SIMILAR DIAGRAM OF Crow (Corvus capellanus).
a, rudiments of sternal attachment of oblique septum. Other letters as in fig. 26.
part of the oblique septum is largely covered with a thickish
layer of muscular fibres, which FILHOL ? (their describer in
1 BEDDARD, 'Notes on the Visceral Anatomy of Birds,' II. 'On the Respi-
ratory Organs in certain Diving Birds,' P. Z. S. 1888, p. 252.
? Sur la Constitution du Diaphragme des Eudyptes,' Bull. Soc. Philom. (7),
vi. p. 235.
42
STRUCTURE AND CLASSIFICATION OF BIRDS
Eudyptes) has termed 'muscle diaphragmatique transverse.'
These muscles are, however, striated; but the duck is not
the only bird with unstriated fibres in the oblique septum,
for these also occur in the toucan.
In all birds, with the exception of certain passerines--
possibly of the entire group of passerines—the oblique septa
have the structure and relations that have been thus briefly
described. In passerines they have undergone what appears
to be a modification. The oblique septa of each side, instead

NH
A
www.
M
VIS
SA
mer
SA
VU.
.
.
.
..
U
www
.
.
.
S
21
wwwwwwwwwww
.
.
.
.
..
1
.
.
.
.
+
.
.
NO
.
..
.
.
..
.
.
...
A
III
.
41.
PHY
ww
.
27
.
1.
LT
ZABEZ
12
.
.
4-
1111111
2
1
.
www
SS
Die
.
W
WW
WIN
VROIT
.
USKUVIA TWW
Ulu
Anna
/
/
.
... . .
. ..
. ...
.. .
.
.
M
..
..
*...
MINIT
...
ot
HU
w
MIMI
.
.
119
.
PZINI
Will
-
7
.
1
.
.
Willa
».
.
.
.
.
.
.
.
.
.
.
Un
19
Ni
.
..
.
w
..
**
.
Willy
.
**
.
..
...
17
.
.
V
II
**
INI
INITI
.
**
IN
MUZ
All
.
Till
.
.
.
S
11.
ill
.
.
DOMAINN
WWW.
.
.
SVAY
.
PI
TURINI
UM
IN
NA
.
n
Fig. 28.- VISCERA OF ROOK DISPLAYED BY REMOVAL OF ABDOMINAL WALLS.
S1, gizzard ; L, liver; 0.S, oblique septum. The liver is covered by a membrane
continuous with the oblique septa.
of being attached independently to the sternum, become
fused with the falciform ligament in the middle line, and
form a horizontal sheet of membrane covering over the two
lobes of the liver. The original (?) attachments of the
oblique septa are not, however, in these birds entirely lost;
a much fenestrated membrane-sometimes, indeed, reduced
to a thread or two-remains to remind the anatomist of the
BEDDARD, “On the Oblique Septa in the Passerines, and in some other
Birds,' P. Z. S. 1896, p. 225.
THE CELOM
43
more prevalent conditions. In the rook, however (fig. 28),
they are completely preserved. But the attachment of the
falciform ligament to the sternum in the median line is lost.
The cutting off of two lateral sections of the body cavity
by the oblique septa, and the division of the remainder by
the horizontal septum, do not, however, exhaust the sub-
divisions of that space. The liver lobes are attached, as is
so common among reptiles, to the oblique septa, in the
neighbourhood of the lungs, by what may be termed the
pulmo-hepatic ligaments. In making the comparison with
reptiles we assume for a moment the correctness of BUTLER'S
contention that the oblique septa are in reality a portion of
the pulmonary aponeurosis, a view which will require a
careful re-examination. This ligament assists in closing
the pulmo-hepatic recess, which is really an extension forward
of the abdominal cavity, as shown by MALL's instructive
figures of casts of the perivisceral cavity of birds. They are
narrow cavities, one on each side of the body, walled and
floored by the ligament mentioned, and by the oblique and
horizontal septa. The aperture of entrance has been com-
pared to the foramen of Winslow of the mammal, and so
named. In some birds there are no further complications of
the thoraco-abdominal coelom, but of others there are still
a few facts to relate before dealing with the homologies of
the various spaces and membranes. In the Australian pas-
serine Struthidea cinerea the liver lobes are each partitioned
into two by a transverse septum, which runs from the falci-
form ligament in the middle line to the oblique septum on
either side. This septum, which is clear and transparent,
does not actually divide the liver lobes; it arches over each
with a free crescentic margin. In some other birds similar
septa are present, with very nearly the same relations. In
hornbills, cuckoos, and owls--at any rate in some species
of each family—the two liver lobes are each completely
shut off from the ventral section of the abdominal cavity
(the 'subomental space,' as it has been termed) by delicate
partitions, of which one only, the left, is present in some
other birds, e.g. Chrysotis Guildingi. The same appearance
44
STRUCTURE AND CLASSIFICATION OF BIRDS
is occasionally presented by birds in which the horizontal
septum is very short, and therefore almost vertical in direc-
tion. But in the birds mentioned the septa are perfectly
C-

.
TITA
:12
C
1
.
www.
OT
rom
PERO
www
USA
.
.
.
www
EST
.
.
ww
www
ES
11 ITA
BR
CU
LE
w
WW
1/
.
VITO
w
w
.
A UN
+
www
AL
P
.
TA
.
ww
www.
top
SCAN
-
ve
w
.
.
ww
wwwwwwwwwww
.
w
.
.
I:
HALUANA
19.
WIL.
DONNA
ill
.
A
***
1
*
-
WWW
.
*
R
-
Hunt
LUE
A
.
-
.
h
4
.
ws
.
1.
ther
-
-
-
-
SOSY-
.
RAS
.
+
.
.
C
SAN
he
URS
id
.
.
COLA
RH
STYS
sty
X-
MERA
IST
99
27
ANZA
re
2.
04
A
*.
**
,
STIG
.
0
NO.
.
***
3Rn
MASA
St.
Vi
AL
Show!
S
I
S
-.
-
:
.
1
IN!!
U1111!
TOYO
St
21.
SDM
.
..
17
.
CE
S
i
l
M
1.
M.
ES
1
25
.
.
.
IT
W
::
!
.
.
,
!
HAIN
L.
UTE
tt
lpe
14
Uhr.
EST
WA
.
.
R ES:
EYKDI
.
A
..
......
!. .
.
...
.
...
.
.
.
- RATSIZ
.
.
--
1942
na
:
. .!
SAAT
.
in
.
2007
ATTIRE
.
..
1
PENER
C
Z
LR
***
.
1
-
..
...
CHEL
.
Y
--
-
here
.
-
...?/
won
...
!
W
.
.
,
.
....
...
.
....
::.
2.
PA
.
.
!
!
..
!
-
.
www.
i
.
...
...
s
.
VIAN
.
.
11:
AT
2
..
+
.
FL-
.
.
..
.
..11
W
.
.
.
TITATEKNIINCIT/
..
.
.
.
21
.
..
..
.
TML
.
H
.
.
I
.
.
.
.
.
.
.
.
.
+
.
...
.
..
.
.
. ..
.
.....
.
.
1
+
.
..
.
.
.
.
..
.
.
Hit
..
X
.
.
w
t..IL
.
...
.
WTA
IEE1
..
!!
.
NZD
.
-
+
.
.
il-
.
1
.
-
.
.
AN
"
.
"
.
.
NI
1
.
.
.
.
49
. .
N
1
....
.
210
207
Sret
.
1
1111111
.
1
#
12
151
A
VA
.
.
SC
2
.
.
.
.
RWIN
.
.
WHITE
13
.
..
.
.
.
IN
.
.
...
..
.
.
.
..
.
WA
.
01.
.
.
.
.
.
.
.
..
.
11
NI
mi
UP
I
WWW
SLWN16
MY
MI
.
IM
HAM
...
IPOH
.
.
.
.
VE
119
.** *. * . .
www.
www
*
.
-
WY
.....
Our
**111.
.
Oulu
III
TIT
1..
AH
>
*
7
1111.18.
.
.
.
.
.
2
.
.
.
Ai
Vi
***
..
1
.
.
.
. !
1330
.
.
We
W
".
WEBM
.
.
7.41..
7
.
.
.
ve
.
III
tot
.
LIMITIINA
.
.. *
---
Fig. 29.-- ABDOMINAL CAVITY OF Bucorvus.
y, gizzard ; a, band of muscular fibre connecting it with oblique septum; V, um bilical
vein ; L, liver seen through fibrous partition mentioned in the text.
THE CELOM
45
distinct from, and present in addition to, the horizontal
septum.
Homologies of Oblique and Horizontal Septa.—Sir RICHARD
OWEN in the year 1838 described the oblique septa of the
Apteryxl as 'a well-developed diaphragm. His figure;
indeed, is highly suggestive of the mammalian diaphragm,
more so than are (in our opinion) the actual structures
cbservable in the dissection of the bird.. OWEN assumed
that the structures corresponded, contenting himself with
indicating the principal differences between the avian dia-
phragm and the mammalian, and pointing out how Apteryx
was nearer to mammals than any other bird. This assumption
was undoubtedly based upon current opinions of the day, for
in the 'Leçons d'Anatomie Comparée' of CUVIER (ed. 2,
vol. vii. p. 21) such a comparison appears to be drawn. As
OWEN justly observed, the imperforateness of the oblique
septum of the Apteryx is more mammalian than in other
birds, even struthious, where the abdominal air sacs project
beyond it; the obliquity of its direction, too, is paralleled in
the dugong and manatee, and it is furthermore less oblique
than it is in other birds.
SAPPEY and MILNE-EDWARDS also use variants of the
word · diaphragm'to describe what we term in the present
work, following HUXLEY, the oblique septa. But for the two
first-named observers the costo-pulmonary (see under descrip-
tion of lungs, below) muscles also form part of the diaphragm.
The older observers, impressed with certain resemblances
(such as warm-bloodedness) between birds and mammals,
regarded them as more nearly akin than is at present the
belief. HUXLEY devoted much work to the demonstration
of the nearer relationship between birds and reptiles-a
relationship which is now generally held. In redescribing
the respiratory organs of Apteryx HUXLEY pointed out
their thoroughly ornithic character, and remarked that in
this, as in all other cases, the meaning of ornithic peculiari-
ties of structure is to be sought not in mammals, but in
reptiles.' It is on a priori grounds likely enough that there
1. On the Anatomy of the Southern Apteryx,' Trans. Zool. Soc. ii. 276.
-
-
46
44
STRUCTURE AND CLASSIFICATION OF BIRDS
(TTI
are structures in birds comparable to the diaphragm of
mammals; but in that case the likeness would be due to the
derivation of both from a common form, perhaps low down
in the reptilian series. At any rate certain anatomical facts
forbid a precise comparison of the entire oblique septa of the
bird to the mammalian diaphragm, though, as will be shown
in the sequel, there appear to be a few genuine resemblances
which can hardly be got over. HUXLEY emphasised the fact
that in the bird the heart lies behind the so-called diaphragm,
which is moreover not supplied by a phrenic nerve. If com-
parable to any structure in the mammal, it is with the medias-
tinum that they should be homologised. As to the phrenic
nerve, several considerations present themselves; it is, it is
true, a specialised nerve, but it is spinal in origin. Now in birds
it is also branches of spinal nerves which supply the oblique
septa. In the mammal it may be that the pulling out of the
phrenic nerve may be due to a cause similar to that which
has produced the looping of the recurrent laryngeal nerve.
When nerves are drawn out by a change in position, or by an
elongation of the structures which they supply, there is at
least a tendency for their roots of origin, of many, to fuse
into a single nerve; witness, for instance, the limb nerves
arising from the anterior and posterior plexuses. The fact
that the spinal nerves which form the limb plexuses are not
always exactly the same has not led to any very serious
belief in the serial homology only of the fore limbs in any
two vertebrates which show these differences. The lungs,
and consequently the diaphragm (assuming for a moment its
correspondence with the mammalian diaphragm), are further
back in birds; hence their different nerve supply. If we
look upon the posterior portion of the oblique septa, which is
alone, be it observed, muscular, as the homologue of the
lateral parts of the mammalian diaphragm, the rest being
absent, no great violence to the mutual relations of the
different structures concerned will have been done. In any
case it may well be that both the mammalian diaphragm
and the avian have been derived from some such reptilian
structure as is to be seen in the crocodile.
THE COELOM
Professor HUXLEY has made such a direct comparison.
*As in birds, the liver [of crocodiles] lies between the
stomach and the pericardium, and has a peculiar peritoneal
investment, shut off from the great sac of the abdomen; and,
as in the ostrich, the whole circumference of the stomach is
united by fibrous tissue with the parietes. A fibrous expan-
sion extends from the vertebral column over the anterior face
of the stomach, the liver, and the dorsal and front aspect of
the pericardium to the sternum and the parietes of the
thorax, separating the thoraco-abdominal space into a respi-
ratory and a cardio-abdominal cavity, and representing the
oblique septum of the bird.' Further on we read : 'A broad
thin muscle arises, on each side, from the anterior margin of
the pubes; and its fibres pass forwards, diverging as they go,
to be inserted into the ventral face of the posterior part of
the pericardium, and into the ventral and lateral parts of the
fibrous capsule of the stomach, passing between that organ
and the adherent posterior face of the liver, and being
inserted into the fibrous aponeurosis which covers the anterior
surface of the stomach and represents the oblique septum.'
Professor HUXLEY seems, according to BUTLER, to have
included the 'omentum' with the oblique septa in his com-
parison with the fibrous expansion and the accompanying
muscle of the crocodile. I have already pointed out that
• the entire fibrous expansion which arises from the vertebral
column, and extends over the anterior face of the stomach,
liver, &c., in the crocodile represents both the oblique septa
and the omentum in the bird.' A justification for this
opinion is to be seen in the dissection of an emu and one or
two other birds. We have occasionally observed that where
the posterior part of the oblique septa is free from the
abdominal walls, ending, in fact, in a free edge within the
abdominal cavity, this edge is really continuous with the
horizontal septum, as shown in the cut (fig. 25). The
oblique septum is thus merely a fold of the horizontal septum;
they form one continuous structure. As to the muscles of
the crocodile mentioned in the quotation just made from
T' On Apteryx,' loc. cit. p. 568.
48
STRUCTURE AND CLASSIFICATION OF BIRDS
Professor HUXLEY, we have already referred to the existence
in birds of what may be considered their homologue, and we
have only to add that in a hornbill the left-hand portion of the
horizontal septum was muscular—that, at any rate, a strong
band of muscle bound the gizzard to the left oblique septum.
Circulatory System
The bird's heart is very uniform in structure; there are
very few and but slight differences in any part of the heart
between the most and the least specialised forms. It is,
however, in certain particulars equally distinctive in structure,
and differs in a number of well-marked points from the heart
of either reptile or mammal. As might be expected, the
reptile which shows the nearest approximation in the anatomy
of its heart to the bird is the crocodile, while the Monotre-
mata are the mammals which on the other side occupy a
corresponding position.
As with the mammalia the heart is completely separated
into four chambers ; in the bird the heart has perhaps more
of an elongated form than in the mammal, the apex (which,
as in the mammal, is formed by the left ventricle alone) being
rather more pointed than in the heart of any mammal. In
a transverse section through the ventricular walls a notable
difference in the relative dimensions of the right and left
ventricles for the two types is apparent. It will be noted
that in the bird the cavity of the right ventricle is, as it were,
partially wrapped round that of the left, and is in consequence
of a decidedly crescentic form. The cavity of the right
ventricle of the mammal's heart is more oval in form, and is
not wrapped round that of the left. In this particular the
Monotremata stand midway between the bird and the higher
mammals.
The interest of the structure of the bird's heart, however,
largely, for reasons of comparative anatomy, centres in that
of the valve which guards the orifice from the auricle. The
interior of that ventricle has fairly smooth walls, a sculp-
turing so conspicuous in the mammalian ventricle being
CIRCULATORY SYSTEM
49.
almost entirely absent. The valve itself, represented in fig.
30, really consists of two parts, which are distinguished by
the insertion of a large papillary muscle, which ties the entire
valve to the free wall of the ventricle. It is only rarely that
any other representative of the generally numerous papillary
muscles and chordæ tendineæ of the mammalian heart occur,
but occasionally a few muscular threads in addition to the
single papillary muscle are to be found. Their existence has
been noted, for instance, in Apteryx australis and in a few
other birds. It has been usually held that the muscular
right auriculo-ventricular valve of the bird's heart represents


.
.
.
*to
at
int
.
..
A
!
.
r.
XEN
*
.
Yin
2
.
EARL
VA.
.
29r
SI
.
.
3
RAS
1
.
.
..
UNG
.
NIE
.
.
*
.
AS
.
JM1..in
HU
liit1
11
.
.
.
WWE
HA?
BOR
M
1
ROTI
MEATLLLLLLSUN
SIS
.
VIS
*
HARUS:
WWW.Me
1
st
E
VN
MMMM
IKUU
...,
N
LES
.
will
we
T
im.
..
V
Wat?
I
1
*
FIG. 30.—HEART OF FOWL, INTERIOR
or RIGHT VENTRICLE.
papillary muscle ; 0, 0, valve. (After
LANKESTER.)
Fig. 31.—HEART OF Apteryx, INTERIOR
OF RIGHT VENTRICLE, WITH ATTACH-
· MENT OF PAPILLARY MUSCLE CUT
THROUGH.
2, flap of ventricular wall removed with
muscle. (After LANKESTER.)
only one half of the complete valve of the mammalian and
crocodilian hearts. In these last-mentioned animals the
entire circumference of the ostium, which leads from the
auricle into the ventricle, is surrounded by the valve, which
thus forms a complete collar. There is, however, an excep-
tion in the case of the Monotremata, where the septal flap of
the valve (v.e. that lying on the side of the ostium which
abuts upon the interventricular septum) is partially or
entirely absent. On a careful comparison, however, between
· 50
STRUCTURE AND CLASSIFICATION OF BIRDS
the bird's heart and that of the crocodile it appears that this
is not the case. If the hearts of the two animals be
seen that the crocodile's heart valve is furnished with a
muscle which seems comparable to that lettered a in the
bird's heart. And, furthermore, on the septal side of this
muscle the fibres which in the bird constitute that half
that of the fibres in the other and larger half. Finally,
while the larger half of the valve is never, so far as is
known, fibrous in character, the lesser half occasionally
appears to be so wholly or partially. Thus there are some
grounds for thinking that the bird's right auriculo-ventricular
valve is composed of a complete outer half and of a smaller
septal half, presenting, therefore, less difference in this one
particular from the monotrematous than from the crocodilian
heart.
We can, therefore, derive the bird's heart as regards this
valve from a heart like that of the crocodile, in which the
septal flap has for the most part disappeared. But in one
bird at any rate there appear to be traces of a still further
retention of the septal half of the valve. GEGENBAUR, who
some years since wrote an exhaustive paper upon the verte-
brate heart,? made the following remarks about the heart of
the condor, which in translation run as follows :-
Only in the heart of Sarcorhamphus do I find a peculi-
arity which has interest in this connection. From the
anterior origin of the muscular valve on the septum ventricu-
lorum a fold runs backwards, which is formed by a thicken-
ing of the endocardium. The fold runs obliquely backwards
and downwards, and crosses in its direction the margin of
the muscular valve. The course of this fold corresponds to
the line of origin of the membranous valvular flap of the
crocodile ; I think it reasonable, therefore, to regard it as á
1
. See for a fuller account BEDDARD and MITCHELL, 'On the Alligator's Heart,'
P. Z. S. 1895, p. 342.
2. Zur vergleichenden Anatomie des Herzens,' Jer. Zeitschr. 1866 ; ‘Notes
on the Anatomy of the Condor,' P. 2. S. 1890, p. 142.
CIRCULATORY SYSTEM
51
remnant of the structure which is further developed in the
crocodile.
I have, since that sentence was written, examined
the heart of a condor, in which was found along a line corre-
sponding to where the flap would be, were it present, 'a
series of tiny yellowish spots and vesicles ... probably
pathological,' but perhaps, like other pathological structures,
associated with a rudimentary structure. With this excep-
tion no trace has ever been found of a septal flap other than
the small flap already described.
The left ventricle of the bird's heart has an auriculo-
ventricular valve, which is completely membranous, and is
tied to the parietes of the ventricle by tendinous threads
attached to papillary muscles.
'There is one more structure occasionally present in the
right ventricle of the bird to which we must direct attention
before leaving the matter. The late Professor ROLLESTON,
in his Hunterian lecture, described and figured in the heart
of the cassowary a muscular pillar uniting the free and
fixed walls of that ventricle, to which he gave the name of
moderator band. This structure occurs in a few other birds
-for example, in Chunga Burmeisteri, where it has been
figured. In the latter, bird, however, there are two muscular
bridges, which run in the same direction. One of them is also
connected with the muscle tying the auriculo-ventricular valve
to the free wall of the ventricle. This may conceivably be a
rudiment of the septal half of the valve lying to the right side
of the heart. In any case these moderator bands, which
are also found in deer and in other running animals, seem
to be, according to ROLLESTON'S suggestion, a mechanism
for increasing the power of the ventricle to contract, and
thus ensuring a more rapid and regular flow of blood into
the lungs. It is characteristic, where it occurs, of running
animals.
· ·! For other facts about the avian heart see A. SABATIER, * Etudes sur le
Coeur,' &c., Ann. Sci. Nat. (5), xviii. 1873, art. No. 4; F. R. Gasch, - Beiträge z.
vergleichenden Anatomie des Herzens,' Arch. f. Natury. liv. 1888, p. 119;
C. RÖSE, "Beiträge zur vergleichenden Anatomie des Herzens der Wirbelthiere,
Morph. J.B. xvi. 1890, p. 27.
52
STRUCTURE AND CLASSIFICATION OF BIRDS
The arterial system of birds is chiefly remarkable for the
large number of the different arrangements of the carotids.
SA


1.5
ris.
T.BE
FIG. 33.—CAROTIDS OF BITTERN.
LETTERING AS IN FIG. 32.
FIG. 32.-NORMAL AVIAN CAROTIDS.
2.c, 2.c, carotids ; 1., 1.s, subclavians ; 7.1, 7.1,
riglit and left innominate; al, aorta ; h,
its origiu. (This and five following figs.
after GARROD.)


1.5
i
FIG. 34.--CAROTIDS OF FLAMINGO.
LETTERING AS IN FIG. 32.
FIG. 35.—CAROTIDS or Cacatuc.
LETTERING AS IN FIG. 32.
Many writers, especially NITZSCH, among the earlier anato-
mists, have drawn attention to some of these variations.
IL. A. NEUGEBAUER, 'Systema Venosum Avium,' Nov. Act. Acad. Nat. Cur.
xxi. 1845, p. 517; RATHKE, “ Über die Carotiden ... der Vögel,' Arch. f. Anat. 26.
Phys. 1850, p. 184, and 'Bemerk. über die Entstehung, &c., der gemeinsch.
Carotis,' ibid. 1858, p. 315 ; GARROD, 'On the Carotid Arteries of Birds, P.Z. S.
1873, p. 457; C. H. WADE, 'Notes on the Venous System of Birds, J. Linn
Soc. xii. 1876, p. 531; F. HOCHSTETTER, - Beiträge zur Entwicklungsgeschichte
des Venensystems, &c., Morph. J.B. xiii. 1888, p. 575, and. Über den
Ursprung der Subclavia d. Vögel,' ibid. xvi. 1890, p. 484.
CIRCULATORY SYSTEM
But the whole matter was described at considerable length
by GARROD, who had more abundant material to work upon,
but who, nevertheless, left for his successor FORBES one out
of the eight known types to describe. The most prevalent
type is that illustrated in fig. 32. It characterises a large
number of birds. The two carotids are of equal size, and
run up the neck for the latter part of their course in the
hypapophysial canal. A modification of this (fig. 33) is seen
in the common bittern and other birds, where the carotids
are of equal size, but fuse into one trunk early in their
course. In Phænicopterus the right (fig. 34) and in Cacatua


Pis
1.C
ris
Fig. 36.---CAROTIDS OF PASSERINE.
LETTERING AS IN FIG. 32.
Fig. 37.--ABNORMAL ARRANGEMENT
OF CAROTIDS, WHERE THE LEFT IS
SUPERFICIAL IN POSITION.
sulphurea (fig. 35) the left of the two trunks, which are later
fused together, are very much the smaller. This state of
affairs leads to the condition shown in Passeres, where the
left carotid alone is present (fig. 36). Quite exceptionally,
and only seen in two species of the bustard, genus Eupodotis,
the right carotid alone is present.
A very curious modification of the carotids is seen (ex-
ceptionally, according to FÜRBRINGER) in the hornbill,
Bucorvus. Here the two carotids are entirely superficial,
running up the neck in company with the vagus nerves. In
this case, as OTTLEY discovered, the true carotids are reduced
to the condition of white imperforate cords, the developed
54
STRUCTURE AND CLASSIFICATION OF BIRDS
(
carotids being the equivalents of the comes vagi nervi of
other birds. FORBES thought that the same might be the
case with Leptosoma, where the carotids are unusually
small, and apparently bound together, not absolutely fused,
as also in Opisthocomus. In certain parrots the left carotid
artery is superficial, while the right runs in the ordinary
way within the vertebral canal. This is illustrated in the
accompanying figure (fig. 37). A final variation has been
observed by FORBES in the passerine Orthonyx, where the
left carotid, as in all passerines, is alone present; but it runs
superficially, and there is no deep right carotid, as in the
parrots, just referred to. These facts, striking though they
are, are unfortunately of but little value in classification, or
at least their value is not understood. We may, however,
accept FORBES's statement that 'no passerine bird has ever
yet been found with more than a left carotid, and no pigeon,
duck, or bird of prey without two normally placed ones.'
In all birds, as is well known, the right aortic arch ? has
alone persisted. It is, however, a commonplace of the text-
books to mention the fact that the Raptores have often a
ligamentous rudiment of the left. There are occasionally
(perhaps individual) remains of the left arch more conspicu-
ous. Thus I have found a considerable tract of the left arch
capable of being injected, and measuring quite an inch in
length, in Spizcetus and in the hornbill Aceros. Cariama,
I may mention, has (at least sometimes) a ligament repre-
senting the otherwise aborted left aortic arch.
A variation in the thigh arteries has been noted by
GARROD, who found that in some birds the ischiadic, in
others the femoral, was the most important. In Passeres the
neotropical Clamatores were termed by him Heteromeri,
since the femoral was the principal artery; other Passeres
(including, however, the neotropical and clamatorial genus
Rupicola) Homcomeri, from their ischiadic artery. The fact
? J. Y. MACKAY, · The Development of the Branchial Arterial Arches in
Birds,' &c., Phil. Trans. clxxix. 1889, p. 111 ; J. F. VAN BEMMELEN, ' Die Visceral-
taschen u. Aortenbogen bei Reptilien u. Vögeln,'. Zool. Anz. ix. 1886, pp. 526,
543.
CIRCULATORY SYSTEM
55
:
that in different species of the same genus (Centropus) the
same Variation occurs tends to throw considerable doubt
upon the value of the character, an observation that is fre-
quently and unfortunately necessary to make in describing
the anatomy of birds.
The descending aorta gives off three branches, which
supply the alimentary canal. These are, in order of origin,
the coeliac, the superior, and the inferior mesenteric. These
arteries do not, however, supply certain definite regions of
the gut. Thus in Bernicla rubidiceps the left cæcum
receives its blood both from the coeliac and from the superior
mesenteric. The right cæcum, however, appears to be
supplied by the superior mesenteric alone. The coeliac is
mainly concerned with the blood supply of the stomach and
the liver. In Porphyrio the two cæca are provided with
blood from both coeliac and superior mesenteric. A dissection
of Platalea leucorhodia showed that roughly the coeliac was
concerned with the blood supply of the duodenal loop and
of the posterior part of the intestine; the mesenteric, on the
other hand, supplied the anterior part of the intestine, ex-
cepting the duodenal loop.
In a few birds (e.g. in Buceros and Haliaetus, GADOW)
the coeliac and superior mesenteric arise from a common
stem. .
The posterior mesenteric supplies the end of the alimen-
tary tract. The aorta also gives off two spermatic arteries,
and on either side a crural and an ischiadic.
We shall deal briefly with the venous system, since it has not
been up to the present largely used for systematic purposes.
This is doubtless due in a great measure to our imperfect
knowledge of the variations that occur. As in the lower
mammalia, there are two venæ cavæ superiores. These
are formed by the union on each side of a jugular, a sub-
clavian, and a vertebral. The two jugulars are often of very
unequal size; the right is usually stronger than the left, but
the two veins are connected in the neighbourhood of the
head by a transverse branch. Sometimes the left jugular
may absolutely disappear. Connected with the subclavian
56
STRUCTURE AND CLASSIFICATION OF BIRDS
are several veins which extend on to the pectoral and even
on to the abdominal region of the body. Most important
on physiological grounds of these is the abdomino-pectoral,
which on each side of the body collects blood from the
pectoral and abdominal regions, and forms in the female
during the breeding season a network of vessels with the
corresponding arteries.
The vena cava inferior is composed of the two hepatic
trunks and of an unpaired median portion, the main stem of
the vena cava. The latter traverses the right lobe of the
liver, and in its transit receives several smaller twigs from
the liver. At the commencement of the kidney the vena
cava divides into, or rather is composed of, the two venæ
iliacæ. It has been pointed out that in diving birds the
part of the vena cava which traverses the liver is wider than
in other birds, a state of affairs which is paralleled in certain
aquatic mammals.
The two common iliacs divide each of them into two veins,
of which the first to be given off is termed the vena iliaca
externa. This divides at once in the pigeon (according to
JOURDAN) into the femoral and into a trunk which runs
along the kidney, and after giving off the sciatic and
numerous branches to the kidney substance receives the
hypogastric from the pelvic region, and then joins its fellow
in the middle line; at the point of junction of the two
iliacæ externæ a median coccygeal is received, and a median
mesenteric from in front. The other branch of the iliaca
communis is purely renal. It results from what has been
said that blood entering the kidney from any of the
branches of the common iliacs may traverse the kidney
substance before reaching the heart via the vena cava
posterior. The suprarenal bodies also have their portal
system. The body of each side receives a branch from the
rib region and from the branch of the iliac which runs
embedded in the substance of the kidney.
The existence of a renal portal system in birds is
therefore possible, but not certain, on the anatomical facts.
available; but the liver portal system, as in all other verte-
CIRCULATORY SYSTEM
57
7
I CU UN
brates, is quite certain. All the blood from the alimentary
canal, however, need not reach the heart via the liver.
In Aceros nipalensis the vena cava inferior receives three
veins from the liver, the abdominal vein (see below), and a
smaller twig which is compounded of branches from the
oesophagus. Moreover the blood from the posterior part of
the intestine, at any rate, may reach the system of the vena
caya inferior via the mesenteric vein, which, as already
stated, enters the iliacs at their point of junction in the
middle line.
In addition to the main portal trunk a number of small
veins (five on the left side in Chauna chavaria) may enter the
liver lobes separately, a state of affairs which is precisely
that found in lizards.
The umbilical vein, which is the equivalent of a part at
least of the anterior abdominal vein of the lower vertebrata,
is found in very various conditions of degeneration among
birds. In some it appears to be fairly well developed ; in
others it is practically absent altogether. In a specimen of
the hornbill Aceros nipalensis it was as well developed as
I have ever found it in birds. The vein arose near to the
posterior end of the abdominal cavity as a double vessel ;
further forward the two halves joined to form a single
vessel. The vein is supported by the falciform ligament,
and the upper of the two component vessels receives, not
very far from the junction of the two, a recurrent vessel
from the inside of the sternum. It may be that the
recurrent nature of this vessel is one among many hints of
the shortening of the sternum among birds. The anterior
abdominal trunk does not enter the liver, but joins the
hepatic vessels, and its blood is conveyed straight to the
heart.
In Platalea leucorhodia I could find no trace of an
anterior abdominal vein in the falciform ligament. In Grus
monachus it was very small ; in a large number of other
birds of different families the vein was present and large, e.g.
Crax globicera, Spizaetus coronatus, Serpentarius, Bucorvus,
Chauna chavaria, Botaurus stellaris, Bernicla brenta, &c.
Inn
UUTUU
2
VLU
VU
58
.
STRUCTURE AND CLASSIFICATION OF BIRDS
210manam
porno
NEM
W222
595 Surinamento
ASI
,
otroTV21
SURI!
NOWA
Respiratory System
Trachea.-As a general rule the trachea is a straight tube
passing into the thorax, where it bifurcates into the two
bronchi. It is composed throughout of rings, which are
cartilaginous, or may be
wholly or partially ossified.
The rings are generally
simple rings, which are like
each other and quite com-
plete, excepting just at the
bifurcation, where it is com-
mon for them to be modi-
fied in connection with the
formation of the syrinx.
This is especially marked
in the tracheophone Passeres
and in the Ciconiidæ, to the
accounts of which families (as
well as to below, “Syrinx')
reference inust be made for
the facts. Other modifica-
tions of some of the last
s.t. tracheal rings are to be seen
in the cassowary, where the
last few are incomplete
behind, as in the mammals
and in the bird of Paradise,
Seleucides (see fig. 38), where
the membranous interspaces
between the rings become
FIG. 38.-WINDPIPE OF Seleucides nigrci.

T
EA-8
SW
D
-7
RA
+
.
3
-
5
*
.
A
*
WH
ph
www.
W
&
M
.
-
.
.
YA
V
.
.
a
.
.
RK
*
Mt.
.
A
.
DIATAS!
4-11, tracheal rings; III, third bronchial;
sterno-tracheal muscles. (After FORBES.)
i c
onifiat both icon
ORBES.) rings ossified' at both sides,
but not in the middle, in a peculiar fashion.
A peculiarity of the trachea, seen in representatives of
some most diverse groups of birds, is its looping. This is,
of course, suggestive of the similar looping of the trachea in
RESPIRATORY SYSTEM
69
crocodiles and chelonia. The occurrence of this state of
affairs is not a character of any one group, but it is found
Tr.

S
VIIVIHII
VIS
V
LA
.
Enters into Body
UKE
.
10
ON
mm
INA
ti
CD
CE
/
.
.
i
.
.
VP
HII
.
aprI
/
DUNIANIKA!
h
X2
.
N-
.
"
r
.
DA
.
LE
WA
5
De
.
.
.
Ne
.
.
21
.
4
1:1
.
77/
.
.
hi
.
.
.
11
.
ITI
M
IL
.
NU
-
14
.
We
2
..
.
.
#
YA
#
.
71
RU
VIYAT
:
.
WA
//
I
.
-
.
-
7
-
-
WYDAWNICZE
ANIM
..
):13
ANAAN
w
D
.
Simm
YEV
7 TT
w
S
.
f
..
AN
MIN
URA
WS
A
LAS
.
.
riin
FALLLESTETICE,
!!
17
.
WEB
.
:
M
AVUI
llllliliid 1111111
CANADA
S
W
Z
il!!
W
L
M
Bath
7
S
"g
ASSON
A
011111111 Wilschen
NA
W
:
،را بالذاالا
www
..
VA
RSS
Tax
11
MAS
.
.
amitin
ST
ma
.
!\|| 11:1111111
Fenil
YAY
IV
VW
le
tar.
1
W
.
ti
TERBIL
AWS
S
AUDIN
With
!!
I
-
*
**
w
.
MWILHO
EN WIL
Why
!
w
cer
www
ww
19
.
UWA
.
T.
NE
Ali H04
WAIIIII
TI
***
VITA
CS
YA
IMA
.
NIHIN
wwww
.
-
INI
VY
AI
PO7
2
de
..
.
.
.
RE
.
0
*
T
ON
IIW
Fig. 39.—BREAST REGION or Manucodia.
?r, trachea ; P.M, pectoral muscle ; l'cm, femur.
sporadically, as it were, in members of quite different groups.
The facts have been collected into a general account of the
7
TO
60
STRUCTURE AND CLASSIFICATION OF BIRDS
C
matter by FORBES. There are various grades of this
lengthening of the trachea. In certain species of Phony-
gama and Manucodia among the Oscinės the loops, which
vary in complication, lie, as is shown in the figure of
Manucodia (fig. 39), beneath the skin. Many of the cura:ssows,
a few Scolopacidæ (Rhynchæa australis and R. capensis), the
duck Anseranas melanoleuca, have a convoluted trachea of
the same kind. In the male of Tetrao urogallus the loop is
present, but is in the cervical region, not in the thoracic
and abdominal, as in the types just referred to.
The Syrinx.—The voice organ of birds, usually termed
the syrinx, is, as is well known, situated at the bifurcation
of the two bronchi. Its complexity varies greatly, though
it cannot be said that a complex voice organ necessarily
implies an elaboration of sound-producing power. Some of
the singing birds and the parrots, whose voices are capable
of emitting a great variety of tones, have, it is true, a much
specialised syrinx. But, on the other hand, there are other
passerines which have just as complicated a syrinx, but can,
like the raven, by no means vie with some of the starling
tribe, for example, in range of sound. Then, too, some of
the singing passerines have syringes which are much simpler
than those of others which sing as well and no better.
It is, however, true that in the least differentiated forms of
syrinx the bird has but one or two notes. The ostrich, for
example, which has one of the simplest syringes, can roar,
but possesses no variety of sound. The Apteryx, whose
syrinx is about on the same level of organisation, appears
to be absolutely mute. The sounds of the emu are due
not to its simple syrinx, but, chiefly at any rate, to a
throat pouch, to which due reference will be made later.
The syrinx of birds, as has been said, varies considerably
in structure. Many of the variations will be treated of in
the systematic part of this book, since they are more of
systematic than of morphological interest. In this place,
however, the leading modifications of the organ will be
T'On the Convoluted Trachea of two Species of Manucode, with Remarks on
similar Structures in other Birds, P. 2. S. 1882, p. 347.
C
RESPIRATORY SYSTEM
ULU:111019multilillent
IIIIII.
WWW
SHIM
UUNI
WWWWWWW
Uuunnititu
m
utltipli
171
shortly described. The syrinx is an organ special to birds;
there are no hints of it in any reptile. In reptiles there is
no modification at the bifurcation of the bronchi; the tube
simply branches, and there are two sets of cartilaginous
rings where there was but one. In birds the case is
different, and it may be convenient to commence with what
may be regarded as the typical avian syrinx, which has been
termed the 'tracheo-bronchial, since the end of the trachea
and the beginning of the
bronchi take a share in its
formation. It is fair to term
this the typical syrinx, since
it is found in the majority of the
groups of birds; it occurs, for
instance, in such diverse families
as Passerines, Ardeidæ, Rallidæ,
Struthiones, Picariæ, &c. The
accompanying cuts illustrate
this form of syrinx in a number
of birds, and from an inspection and
of them the principal features
in the organisation of this form
of syrinx may be gathered.
At the end of the trachea there
is usually a certain amount
FIG. 40.-SYRINX Of Indicato ,
of modification of the tracheal
rings, which may be more or a, first bronchial semi-rings. (After GARROD.)
less marked, and may be in different directions. It is not
necessary to particularise here, and we can select fig. 40
to illustrate one example of this modification, which consists
in a complete fusion of the last few rings of the trachea.
The bronchi are formed at first of the short semi-rings, the
wide interspace being occupied by membrane, the tympani-
form membrane, which closes them internally; the extent
of this membrane varies, and below it the bronchial semi-
rings become more closely applied—sometimes, indeed,
becoming complete rings. The tympaniform membrane of
each bronchus is separated from its fellow by a cartilaginous

III/
WHINI
.
'
HU
WC
NU
WLINE
WISCONSIN
WWW
UUS HIS
manninn
TU
W
SWAMY
NIM
MWMUWN!
UWWII
WITHUB
2
. . . 11
tyret
II
ar
lunanji
ENLARGED.
62
STRUCTURE AND CLASSIFICATION OF BIRDS
or bony bar, which runs across the base of the trachea,
arising from the last tracheal ring anteriorly, and attached
to the penultimate or antepenultimate ring posteriorly.
This bar is called the pessulus. It is shown in fig. 41,
which represents a syrinx seen from below. When the
syrinx is cut open it may be seen that this bony bar bears a
tough semilunar membrane, directed upwards between the
bronchi; the voice is due to the vibrations of this mem-
brana semilunaris.
Another external feature of the typical tracheo-bronchial
syrinx is the presence of a pair of mus-
cles which arise some way up the trachea
and are inserted on to an early semi-
ring of the bronchial series, one on each
side, or even to the last or nearly the last
of the tracheal series. From this starting
point we can follow the modification of

hummituto
nc
mane
TO
1191 rdt
KULTT12:31
ALATELITALIE NTS
שיש שם
מידע
DANTE
SUNT
ht,
Bumwam
JUIST
LowerPLE
K
LIT
UNNATOU
BUSTETTI
atzinur
W
ASHIL
ABOUT

hip
mutta
his
Annemin
for
members
animemuunning a 1032DAFIR:
JanuCITINUATION
niinilliumok
Slibilmente me
DOMINULLUMAT
ET
MOUTFIT
WITALIANO
MULTIMI Autourmet
qui ruumallin
Withnja mlinUAINE
ultimumin U11
:
*
FIG. 41.-SYRINX OF Cymbirhynchus,
x 5, FROM BEHIND (AFTER FORBES).
FIG. 42.-SYRINX Or Balcriceps.
En, ligamentous rudiment of intrinsic
muscle.
the syrinx in a number of directions—in the way of com-
plication, in the way of simplification, and in a direction of
alteration which can hardly be termed either complication or
simplification. .
The first sign of simplification is the disappearance of
the intrinsic syringeal muscles, which in many forms have
completely disappeared. The disappearance is not neces-
sarily associated with any other changes in the general
structure of the organ. Occasionally, as in Balaniceps (see
RESPIRATORY SYSTEM
63
fig. 42), the former presence of the muscle is testified to by
a thin ligament, which occupies the position that the muscle
would occupy were it present.
The syrinx of the hoatzin shows an intermediate stage ;
the muscle is absent for the lower part of its course, but
present above; it is represented below by a fibrous band. It
seems from what we know of the relation of muscle to
tendon generally that this change is in the direction indi-
cated and not in the converse direction. The fibrous band of
the syrinx of Balaniceps has, so to speak, been muscle; it is
not on its way to become muscle. The ostrich affords an
example of a further degeneration of the syrinx, or a reten-
tion of a very primitive and unspecialised syrinx, according
as we view the facts. The syrinx of this bird has been care-
fully described and figured by FORBES,' whose words we will
quote. The trachea inferior to the insertion of the sterno-
tracheales slightly narrows, having above the antepenultimate
ring a diameter of about oneinch. The tracheal rings are here,
as elsewhere, entire simple rings of an average depth of about
.15 inch, and are separated only by very slight interannular
intervals. The trachea is slightly compressed and posteriorly
carinated for about the last seven rings. The last ring but
four is somewhat produced downwards in the middle line
both anteriorly and posteriorly ; it is in consequence nar-
rower laterally than elsewhere. The antepenultimate ring
presents the same features more strongly developed. In
two of the four specimens examined it sent down a small
pessuliform process of cartilage in the middle line behind,
filling the chink left between the posterior extremities of
the last two (incomplete) rings. The penultimate ring is
narrower and more cylindrical than its predecessors; it is
also wider transversely, and incomplete behind in the middle
line, its extremities, however, being closely approximated to
each other. The last tracheal ring is still wider transversely,
and more cylindrical; and it, too, is incomplete posteriorly
to a greater extent than its predecessor; viewed from the
T. On the Conformation of the Thoracic End of the Trachea in the "Ratite »
Birds,' P.Z. S. 1881, p. 778.
64
STRUCTURE AND CLASSIFICATION OF BIRDS
side it is convex upwards, as are its immediate predecessors
in a less degree. The interannular intervals between all
these rings are, when undisturbed, mere chinks filled up

Lenov
KUDHIBA
FIG. 43.-SYRINX OF Struthio.
, last, oo, penultimate, 000 antepenultimate tracheal rings; 1, section of wall of winl.
pipe to show vocal chord ; 1-7, tracheal, I, II, bronchial rings. (After FORBIS.)
by dense fibrous and elastic tissue. There is no trace of a
pessulus, though the last tracheal ring is slightly produced

OO
FIG. 44.—THE SAME SYRINX FROM BEHIND).
downwards in front. The first bronchial semi-ring on each
side is narrow and cylindrical, strongest anteriorly, and
somewhat attenuated posteriorly. It is separated only by a
LO
LU
RESPIRATORY SYSTEM
65
narrow interval from the last tracheal ring. The second and
third rings are similar, but are more slender and lengthy;
they are convex downwards, but very slightly so; hence the
interannular intervals are slight here also. Their anterior
ends are very slight, inturned, impinging but to a small
extent on the membrana tympaniformis, which completes
the bronchial tubes internally, and, in consequence of the
absence of any three-way piece, passes continuously from
one bronchus to another, so closing the tracheal tube in-
feriorly. The fourth, fifth, and succeeding bronchial rings
are similar in character, but their ends, which tend to be
dilated posteriorly, are successively more and more incurved
to about the tenth. Nowhere are the bronchial rings com-
plete. There is at most only a trace of a membrana semi-
lunaris, in the form of a feeble, scarcely raised antero-pos-
teriorly directed fold of mucous membrane.'
This syrinx, therefore, differs from the more typical
tracheo-bronchial syrinx in, at any rate, three essentials-
(1) the absence of tracheo-bronchial muscles; (2) in the
slight amount of specialisation of the last rings of the trachea ;
and (3) in the absence of a pessulus. The only distinguish-
ing feature of the syrinx which is present is the membrana
tympaniformis. But the presence of this, and of the rudi-
mentary membrana semilunaris, fully justified FORBES in
contradicting the assertion, prevalent at the time when he
wrote, that the Struthiones had no lower larynx,' an assertion,
indeed, which could not possibly be made with the syrinx of
Rhea, a quite typically tracheo-bronchial one, in existence.
Still, it is undoubted that the syrinx of the ostrich is in a
very simple condition, and hardly deserves the name. In
the stork tribe we have a series of stages in the degeneration
of the syrinx. In Abdimia sphenorhyncha, as in other
storks, there are no intrinsic syringeal muscles, but the
meinbrana tympaniformis is well developed and of consider-
able extent. In Xenorhynchus the membrana tympaniformis
is almost, but not quite, obliterated, and, finally, in Ciconia
the bronchial rings are rings, and not semi-rings ; there is in
them no trace of a membrana tympaniformis ; but in all the
22
LU
*
66
STRUCTURE AND CLASSIFICATION OF BIRDS
pessulus is present. The syrinx of the stork, indeed, and of
the American vultures very nearly approaches what we
should on a priori grounds regard as the original form of
the syrinx.
In the other direction the syrinx may be further increased
in complication; this is brought about by an hypertrophy of
the intrinsic muscles. The simplest case is that of the
plover, Vanellus cayennensis, figured and described by
GARROD,' whose figure is here reproduced. It will not need
1

TITIO
...
?
D
.....
-
SA
TI
AM
Fig. 45.--SYRINX or Vanella cayennensis, FROM IN FRONT (AFTER GARROD).
much description; the principal change is in the enormously
thickened pair of muscles.
This modification of the syrinx, however, is seen at its
extreme in certain passerines and in the parrots. Here we
meet with a multiplication of the intrinsic muscles, which
may exist to the number of three or four pairs. A syrinx of
this kind, when found in the Passeres, is frequently termed
oscinine, the group of Passeres exhibiting the character being
the Oscines, a term, however, which is not now used in the
classification of the group.
1. On the Trachea of the Tantalus loculator and of Vanellus cayennerisis,'
P. Z. S. 1878, p. 625.
RESPIRATORY SYSTEM
67
In Menura superba, which has been described by GARROD,
there are three pairs of muscles, which are attached to
different bronchial semi-rings; the posterior pair of muscles
are attached to a ring below that which bears the insertion
of the anterior pair, while the remaining middle pair are
inserted higher up again.
We now come to the consideration of those modifications
of the syrinx which will be spoken of neither as degenerations
nor complications. They are parallel modifications, which
-

.
hen
AN
.
.
Will
.
ST
W
www
newww
-
-
:
ON
11
LES
.
Hvis
-
NR:
:
III
AN
-
--
VI
AN
ya
NA
FIG. 46.—THE SAME FROM BEHIND (AFTER GARROT).
can in all cases be traced to the typical tracheo-bronchial
syrinx, though whether they have originated from it is, of
course, a matter of question. To the two varieties of syrinx
which we briefly refer to here the names tracheal and
bronchial syrinx have been giveni, implying the fact that
the modification of the windpipe has taken place in the
one case mainly or entirely in the trachea, and in the other
mainly or entirely in the bronchi.
The tracheal syrinx is distinctive of a group of Passeres
which have been on that account called the Tracheophonæ ;
F 2
68
STRUCTURE AND CLASSIFICATION OF BIRDS
ES
i.
WE
DI
.
N
.
ES
VaR
.
UWLUWILD
-
-
AM
-
P.
SS
AL
- GES
..
.
.
IN
OG
...!
.
.
ZA
.
.
NA
S3
ST
ESS
ES
SA
.
VA
1
SK
IT
ES
SS
S
WWW
EA
.
.
IS
.
MUN
IM
I
VI
1.
2
WIMU MOBILE
S
.
STWO
SY
IS
..
H
S522CFEE
ATOUS
Non
tiningu
Se
LC
ROT
-
-
SA
SHA
..
M
Y.
TT.
TE
.
Sun
IS
-
.
S
.
.
www
-
ES
.
.
-
-
but a syrinx that presents some of the same characteristic
modifications distinguishes the stork tribe. The principal
modification of this type of
syrinx is that a large number
of tracheal rings are altered
in character, in a way which
will be pointed out in detail
for one or two forms. The
tracheal syrinx of the Passeres
wasinvestigated by JOHANNES
MÜLLER,' but GARROD has
added many new facts of
importance to our knowledge
of this kind of syrinx.
In Hylactes negapodius
there are nine tracheal rings
which are very much thinner
than their predecessors; on
the anterior side, however,
there are twenty-three which
are thusaltered. Two or three
of the anterior bronchial
semi-rings are modified and
ossified; from the second of
these on each side is a ridge
of cartilage, the processus
vocalis, which extends up to
the twelfth tracheal ring
(from the bottom). As a rule
these tracheophone Passeres
possess intrinsic muscles to
Fig. 47.--TRACHEA or Tantalus locri- their syringes, but the rule is
lator. a. FROM FRONT. 6. FROM not to
SIDE. (AFTER GARROD.)
not without exceptions, of
which Conopophaga is one,
as well as Hylactes, already described ; others, such as
Furnarius, have the intrinsic muscles. The same form of
syrinx seems to exist in the storks. In Tantalus loculator,
i In Abh. Berlin. Akad. 1845, p. 367.

PER
WWF
-
AS
CE
.
WTON
PER
both
.
www.
SAS
.
KI
.
RSS
.
.
:
si
PS
w
Vle
IN
She
NIN
proye r
.
ES
.
S
.
.
21
S
TM
der
LEH
21
TH
M
WMO
MX
tla
A
NA
INV.
**
6
OTO
.
Mr
217
VI
6
RESPIRATORY SYSTEM
69
MI
- -
0
1
two ID
.
P
NA
IT
!
C
.
III
INI
WS
IN
WIUS
T
:
ON
1111 US
IT
madar
ten
-
-
-
WT.
numatmund
.
za
HU
padona
mali
wurningmont
www
.
S
IT
for instance (see fig. 47), the lowest seventy-eight rings of the
trachea are modified through being thinner than those else-
where, and this portion of the tube is of a greater calibre than
that above. In Ciconia alba: the lowest twenty-nine rings are
thus changed in structure, and “there is a small prolongation
upwards of the lateral portions of the three lowermost
tracheal rings, which forms a consolidated triangular process
on each side, overlapping the next few rings and looking
extremely like the rudiment of the similarly situated proces-
sus vocales of the passerine
tracheophone syrinx, which
resemblance is increased by
the thinness of the neigh-
bouring rings and by their
being flattened from before
backwards.'
The bronchial syrinx is
seen in its most extreme de-
· velopment in Steatornis and
in Crotophaga, where it was
originally described by MÜL-
LER; but other cuckoos and
goatsuckers, as has been
shown by me,l possess also
a syrinx which may be
called bronchial; further-
more, as WUNDERLICH has
shown,” the owl tribe resem-
ble the goatsuckers in this FIG. 48.--SYRINX or Steatornis. FRONT
respect, while there are in- VIEW. (AFTER GARROD).
dications of the bronchial syrinx in certain petrels.
The fullest description of the syrinx of Steatornis, which
we take as a type of the perfectly formed bronchial syrinx,

.
GE
.
GJIRO
NYOS
17
Y
.
VIEW. Utrum
LEONE
Ilgun
fithmone
RES
IT
V
..
NIN
IN
IT
IIN
..
SV
VAT
>
.
.
.
**
*
S
!
*
ST
HOST
1
.
Wilminin
M
2
SEXY
Ciu
C
.
*
WWW
.
2
-
1.On the Syrinx and other Points in the Anatomy of the Caprimulgidæ,"
P. Z. S. 1886, p. 147; 'On the Structural Characters and Classification of the
Cuckoos,' P. 2. S. 1888, p. 168.
? Beiträge zur vergleichenden Anatomie und Entwickelungsgeschichte des.
unteren Kehlkopfs der Vögel,' Nor. Act. Acad. Leop. Cæs. 1884.
S
70
STRUCTURE AND CLASSIFICATION OF BIRDS
is contained in a paper upon the general anatomy of this
bird by GARROD.) From that paper we borrow the descrip-
tion as well as the illustration. It will be seen from that
drawing (fig. 48) that the trachea of the bird bifurcates, as
does the trachea of a mammal, without any modification of
the rings, either tracheal or bronchial. The latter are at first
complete rings; it is not until the thirteenth or fourteenth
-the exact position appears to vary—that the syrinx appears;
here the rings cease to be complete rings, and are semi-rings,
their inner ends being completed by membrane, the mem-
brana tympaniformis. To the first of these modified semi-
rings is attached in the case of either bronchus the intrinsic
muscle of the syrinx.
The transition between this purely bronchial syrinx and
the more usual tracheo-bronchial syrinx is afforded by
various genera of cuckoos and goatsuckers (of which a par-
ticular description will be found later), in which the mem-
brana tympaniformis is placed, as in Steatornis, far down
the bronchus, but which have also a sheet of membrane
forming a continuation of the membrana upwards to the
trachea, which is due to the non-closure internally of the
earlier bronchial semi-rings ; this latter gets more and more
limited in various genera until we have the purely tracheo-
bronchial syrinx, in which the wide membrana tympani-
formis commences at once on the bifurcation of the
bronchi.
The syrinx has undoubtedly some value as a test of
affinity. As to the Passeres, it is, as FÜRBRINGER has
remarked, a 'classical' object for the determination of
relationships. In other families too it is of importance. From
a more general standpoint, however, apparently but little
reliance can be placed on the modifications of this so variable
organ. An approximation to the reptilian condition--in the
absence of any special modification at the bifurcation of the
bronchi-is seen in some of the struthious birds and in the
American vultures. It is not clear, however, that this
simplicity is not a case of the reduction rather than of the
1. On some Points in the Anatomy of Steatornis,' P. Z. S. 1873, p. 526.
n
RESPIRATORY SYSTEM
71
retention of a primitive character. In special cases the
form of the syrinx seems to be of not little value as a mark
of affinity. The peculiar syrinx of the storks, for example,
distinguishes them from their near allies the herons. The
stork-like syrinx of Tantalus is one of the many reasons for
placing it with that family. The peculiar form of syrinx
termed the 'bronchial syrinx' may seem to some to militate
against the value of this organ as a test of affinity ; but, on
consideration, the fact that both owls and goatsuckers
possess it will not seem extraordinary in view of their other
resemblances, while the cuckoos are perhaps not so widely
remote from those two families as they have been placed.
We may have here a clue to the relationship of these three
groups of birds. The complicated (as regards musculature)
syrinx of the parrots is so far an indication of affinity with
certain Passeres. The systematic position of the parrots is
by no means clearly defined, and therefore this indication
of a possible affinity must not be ignored.
: The Lungs and Air Sacs.—The lungs of birds never
depend freely in the colom, as is the case with most
reptiles. They are closely fixed to the parietes, and covered
with a thin and transparent aponeurosis, which is the
peritoneum. So closely are they adpressed to the body
walls that when they are carefully removed by dissection an
impress of the ribs is to be seen upon their dorsal and
lateral surfaces. An approach to this peculiar position of
the lungs in Aves is to be seen in the crocodilia and to a
less extent in the Chelonia and Monitor lizards. In these
animals the lungs are bound down to the parietes, and do
not hang freely, as in the Lacertilia generally and in the
mammalia. The lungs in birds occupy the space between
the first rib in front and the anterior end of the kidney
behind. They nearly meet in the middle line. Seen from
below, when left undisturbed in the body, only the adjacent
structures being cleared away, the lungs present two facets,
an anterior and a posterior; the latter is divided from the
former by.a ridge which does not divide the lung into two
equal halves. The anterior is considerably the smaller.
72
STRUCTURE AND CLASSIFICATION OF BIRDS
When the lung is thus bared it is seen to be provided
with a number of conspicuous orifices where the covering
aponeurosis is deficient; these are termed the ostia, and
they lead into the air sacs. Their number is variable in
correspondence with the variability in the number of air
sacs. The free surface of the lung is supplied with bands
of muscle, which have been termed diaphragm, but which
are called. by HUXLEY? costo-pulmonary muscles. These
muscles arise from the ribs and spread out over the aponeu-
rosis covering the lung; they are, as a rule, extensive,
extending but a short distance from their origin. The
number of these costo-pulmonary muscles varies much
among birds ; but little attention has been hitherto paid to
them. For instance, among the storks the muscles in
question are reduced to a minimum; there are only two
pairs at the anterior end of the lung, which arise not from
ribs, but from the end of the windpipe. In herons, on the
other hand, and in the emu, all the ribs bordering upon
the lungs give off fasciculi of fibres, which in the emu are
of considerable thickness. Each bronchus enters the lung
at a little distance from its anterior end, and sometimes, as
in the condor, the cartilaginous rings cease some little way
before it enters. The bronchus dilates somewhat when it
has entered the lung, and from the posterior end of this
dilatation a tube is continued backwards, which opens into
the posterior or abdominal air sac. This trunk is termed
by HUXLEY the mesobronchium. Further on in its course
the mesobronchium gives off another branch, which opens
into the posterior intermediate air sacs (a description of the
air sacs will be found a little further on). From the
dilatation of the mesobronchium, the vestibule, arise four
other tubes, which are called the entobronchia by HUXLEY
(whose nomenclature is adopted throughout in the present
section). The first curves forward and gives off several
branches, one of which opens into the præbronchial air sac,
while the main trunk is continued into the subbronchial
air sac. The second entobronchium passes dorsally and
1. On the Respiratory Organs of Apteryx,' P. Z. S. 1882.
RESPIRATORY SYSTEM
13
ramifies, a wide branch descending to the subbronchial
ostium. The third entobronchium runs backwards and,
gives off a number of branches. Close to its origin from
the bronchus it opens into the anterior intermediate air sac
by the anterior intermediate ostium. . The fourth ento-
bronchium runs parallel with this; it gives off branches
from its ventral wall, but ends cæcally. In addition to the
entobronchia there are the ectobronchia. These are six or
seven branches given off laterally and dorsally from the
mesobronchium. These various bronchia are in communi-
cation with each other, so that the substance of the lung is
a meshwork.
As a rule there are ten air sacs in birds, which are
arranged in five pairs, five, in fact, arising from each lung.
In front of the windpipe are the præbronchial air 'sacs;
below the trachea are the subbronchial air sacs; the oblique
septa, which have been described elsewhere (p. 38), enclose,
in the duck and all other birds except the Apteryx, two air
sacs, the anterior and posterior intermediate sacs. The
abdominal air sacs lie among the intestines, and are fed by
an ostium which is at the extreme posterior end of the lung;
they have been, as HUXLEY has expressed it, pushed out
from the space enclosed by the oblique septa like a hernia.
In Apteryx, quite exceptionally, these air sacs are not so
pushed out, but lie within the area enclosed by the oblique
septa. The only differences that have been noticed in birds,
apart from those that have been already mentioned, appear
to consist in the number of the intermediate air sacs and in
the condition of the præbronchial. WELDON' has described
the breaking up of the præbronchial in the storks into a
number of sacs, at least five in number, and the complete
fusion of the subbronchial sacs into a single one. The
breaking up of the præbronchial sacs is carried to a more
complete extent in Chauna. In some birds there are three
instead of two intermediate air sacs. I have observed this
in Podargus. In many Accipitres the abdominal air sacs are
"On some points in the Anatomy of Phoenicopterus and its Allies,'P.Z.S.
1883, p. 640.
74
STRUCTURE AND CLASSIFICATION OF BIRDS
07
ULUI
peculiar in that one of the walls of the sacs has got to be
firmly adherent to the ventral parietes, and the walls of the
two sacs enclose between them the intestines, which have
thus the appearance of being enclosed in a special compart-
ment of the coelom. In one or two Accipitres there is the
same subdivision of the intermediate air sacs that I have
referred to in Podargus.
These air sacs communicate with subsidiary spaces lying
among the viscera, between the muscles, in the skin
(particularly in Chauna and several Steganopodes), and
with the bones. The skull, however, is aerated by a set of
spaces which are not connected with the trachea and lungs,
but with the Eustachian tubes and the nasal chambers.
: The literature relating to the lungs and air sacs is large.
In addition to the memoirs already quoted the following
bear upon the matter :-
. F. BIGNON, "Sur les Cellules Aériennes du Crâne,' &c.,
C. R. Soc. Biol. 1887, p. 36.
Idem, “Recherches sur les Cavités Aériennes Cervico-
céphaliques chez les Psitacidés,' Bull. Soc. Zool. France,
xiii. 1888, p. 180.
Idem, Note sur les Réservoirs Aériens de l'Urubu
(Cathartes atra),' C. R. Soc. Biol. (9), i. 1889, p. 39.
Idem, “Contribution à l'Etude de la Pneumaticité,' &c.,
Mém. Soc. Zool. France, ii. 1889, p. 260.
MILNE-EDWARDS, Observations sur l'Appareil Respira-
toire de quelques Oiseaux,' Ann. Sci. Nat. (5), iii. 1865,
p. 137, and ibid. 1867, p. 12.
Idem, 'Sur les Sacs Respiratoires du Calao rhinoceros,'
C. R. 1885, p. 833.
E. FICALBI, “Alcune ricerche sulla struttura istologica
delle sacche aerifere,' &c., Atti Soc. Tosc. Sci. Nat. (vi. 1885,
p. 249).
H. FILHOL, 'Sur la Constitution du Diaphragme des
Eudyptes,' Bull. Soc. Philom. (7), vi. 1882, p. 235.
N. GUILLOT, · Mémoire sur l’Appareil de la Respiration
dans les Oiseaux,' Ann. Sci. Nat. (3), v. 1846, p. 25.
E. SELENKA, 'Beiträge zur Entwicklungsgeshcichte d.
U
RESPIRATORY SYSTEM
Luftsäcke des Huhns,' Zeitsch. wiss. Zool. xvi. 1866, p.
178.
H. STRASSER, ' Die Luftsäcke der Vögel,' Morph. J.B. iii.
1877, p. 179.
G. ROCHÉ, · Prolongements Intra-abdominaux des Réser-
voirs Cervicaux chez l'Autruche,' Bull. Soc. Philom. (8), i.
1889, p. 111.
Idem, •Sur l'Appareil Aérifère des Oiseaux,' ibid. (8), ii.
1890, p. 5.
Idem, 'Contribution à l'Etude de l'Anatomie Comparée
des Réservoirs Aériens d'Origine Pulmonaire, chez les
Oiseaux,' Ann. Sci. Nat, (7), xi. 1891.
H. BOULART, ‘Note sur un Système particulier de Sacs
Aériens observés chez quelques Oiseaux,' Journ. de l'Anat.
et Phys. xviii. 1882, p. 467..
Idem, 'Note sur les Sacs Aériens Cervicaux du Tantale,'
Bull. Soc. Zool. Fr. 1885, p. 348.
Other references are contained in the paper of HUXLEY
upon the lungs and air sacs of Apteryx, already quoted.
Muscular Anatomy
The most general feature of the muscles of birds is the
great length of their tendons of insertion ; the tendency of
For memoirs dealing with the muscular anatomy of several types see
CARUS, · Erläuterungstafeln zur vergl. Anat.,' Leipzig, 1826 (Astur, Falco,
Cypselus); P. HARTING, Observations sur l'Etendue relative des Ailes et le
Poids des Muscles Pectoraux,' &c., Arch. Néerl. Sci. Exact. et Nat. iv. 1869,
p. 33; S. HAUGHTON, 'On the Comparative Myology of Certain Birds,' P. R.
Irish Ac. 1867, p. 524 (Falco, Grus, Anas); G. JAEGER, “ Das Os humero-scapu-
lare der Vögel,' J.B. K. Akad. Wiss. xxiii. 1857, p. 387; LEGAL and REICHEL,
Über die Beziehungen der Grösse der Flugmusk.,' &c., Ber. schles. Ges.
*1879; H. J. MAGNUS, 'De musculis costarum sternique avium,' Diss. Inaug.
Vratislaviæ, 1867, and in Arch. f. Arat., 1869; H. PFEIFFER, "Zur verglei-
chenden Anatomie des Schultergerüstes,' &c., Diss. Inaug. Giessen, 1854;
J. J. PRECHTL, Untersuchungen über den Flug der Vögel,' Vienna, 1846 ;
QUENNERSTEDT, 'Studier i Foglarnas Anatomi,' Lund's Univ. Ansskr. ix. 1872,
p. 4; N. RÜDINGER, 'Die Muskeln der vorderen Extremitäten,' &c., Nat. Verh.
Holland. Maatsch. Wet., 1868; C. J. SUNDEVALL, in K. Vet. Akad. Förh.
1843, p. 303, and Förl. Skandin. Naturf. 1851 ; G. ALIX, Sur les Muscles
Fléchisseurs des Orteils,' &C., Bull. Soc. Philom. xi. 1874, p. 28, and Essai
sur l'Appareil Locomoteur des Oiseaux, Paris, 1874.
*VL
76
STRUCTURE AND CLASSIFICATION OF BIRDS
CU
this is to mass the fleshy and heavy parts of the muscle
about the centre of gravity of the body, a desideratum for a
flying animal. This peculiarity of the muscular system is
especially well seen in the muscles of the leg. The muscular
system of birds is remarkably constant for the species, the
number of variations being apparently, comparatively speak-
ing, but slight. It is true that in but few cases has a large
number of individuals been carefully dissected; but of a
good many species, on the other hand, have three, four, or
even more individuals been dissected from the point of view
of the relations or presence of a particular muscle or muscles.
The muscular system too is apt to be very constant for a
given genus or even a larger division. A glance at the
systematic part of this work will show how trifling are the
variations even between families in some cases. All these
facts lead to the inference that the muscular system in birds
is of very considerable value for classificatory purposes.
GARROD, FORBES, and FÜRBRINGER are the three anatomists
who have laid greatest weight upon the muscular system as
an index of affinity. It is, thinks Professor FÜRBRINGER, the
muscles of the anterior extremity which have the greatest
value of any part of the muscular system. The wing is an
organ which is used in much the same way by all birds
in which it is properly developed. On the other hand the
uses of the muscles of the leg are manifold ; we have hopping
birds, climbing birds, perching birds, swimming birds, &c.
&c. Nevertheless GADOW is inclined to think (with GARROD)
that they are the most important. The existing knowledge
of the muscles of birds is mainly confined to the muscles of
the leg and of the fore limb, a knowledge which we owe
almost entirely to GARROD and FÜRBRINGER, many other
anatomists having, of course, filled up many details. Less is
known about the muscles of the head, neck, trunk, and hyoid
region.
It is curious, indeed, how very few birds have been
at all thoroughly dissected. Apart from the detailed account
of Apteryx by Sir RICHARD OWEN, and of less comprehensive
memoirs by COUES on the diver, by MORRISON WATSON
MUSCULAR ANATOMY
on the penguin, we have only two recent memoirs which
contain anything like a complete account of the muscular
structure of a given type. These are the book upon Corvus
corax by SHUFELDT and a paper by CHALMERS MITCHELL
and myself upon Palamedea. The most comprehensive
general account of bird muscles is unquestionably that of
GADOW in Bronn's Thierreich.' I shall base the following
account of avian musculature largely upon the last-men-
tioned work, adding to it only such details as were inacces-
sible to GADOW at the time of its publication. The muscles
known to vary will naturally be treated at greater length
than those of whose comparative structure but little is
registered. GADOW allows altogether 112 separate muscles
and sets of muscles like those of the ribs, arranged in a
serially homologous row. Some of these are, however,
divided again. Of these, so far as we know at present, the
following are of the greatest systematicimportance, as present-
ing really considerable variations even to disappearance :
Gluteus maximus, gl. anterior.
Obturator internus.
Femorocaudal and accessory femorocaudal.
Ambiens.
Semitendinosus and accessory semitendinosus.
Biceps femoris.
Semimembranosus.
Flexores profundi hallucis et digitorum.
Peronei.
Tibialis anticus.
Pectoralis primus, p. secundus.
Deltoid.
Patagialis.
Biceps.
A12c0ncus.
Expansor secundariorum.
Cucullaris propatagialis.
The value of muscles in classification has been highly rated by
many ornithologists, especially, of course, by GARROD, FORBES, and
FÜRBRINGER. It is, however, only a comparatively small number
78
STRUCTURE AND CLASSIFICATION OF BIRDS
of the total series of muscles in the body that can be trusted much
as evidence of affinity. The ambicns is unquestionably of value as
it is found or not found, as the case may be, through whole groups
whose mode of progression when walking or climbing is as different
as can be. Its total absence from all picarian and passerine birds
is a fact upon which I comment elsewhere. There are very few
groups in which the ambiens may be present or absent, and in
those cases it is often reasonable to separate as distinct families
the genera which have it from those which have it not. This
cannot, perhaps, be done in every case. Some storks, such as
Abdimia, have no ambiens, while the majority have it. There are
auks with and auks without this muscle. The same may be said.
of petrels, parrots, and pigeons. Rhynchops, the only larine bird
without an ambiens, may be, perhaps, rightly elevated to the dis-
tinction of a separate family. These examples, however, are so
few that they may be compared to such singular exceptions as the
absence of the odontophore in the nudibranch Doriopsis, which
does not in the opinion of any one invalidate the great importance
of that structure in arranging the mollusca. In estimating the
value of the ambiens the facts of its total or apparently partial
suppression, referred to below, must be borne in mind. The
entire absence of all trace of the muscle in the owls shows that
they are not necessarily to be placed in the neighbourhood of the
parrots, in which the muscle, when absent, has left traces behind.
YU
Muscles of the Fore Limb
Pectoralis Primus.--This muscle consists of two parts,
the thoracic part, arising from the sternum, and an abdominal
portion, arising from the pelvis. The latter portion, well
developed in lower vertebrates, is slight in birds, and is often
completely absent. The pectoralis thoracicus arises from
the sternum, the clavicles, and intermediate membranes ; it is
inserted on to the humerus. In ratite birds there is no origin
from clavicles, but, on the other hand, an origin from cora-
coids not present in carinates. There is frequently an
intimate connection between the pectoral near its insertion
and the tendon of origin of biceps. The pectoralis is frequently
divided into two portions, the mode of division being twofold.
In Apteryx the coracoidal portion is separate from the sternal,
a state of affairs which recalls some of the lower vertebrates;
MUSCLES OF THE FORE LIMB
79
in others the pectoral is divided into a superficial and deeper
layer. In many Ciconiiformes' this is the case. The
pectoral, in all birds except the ratites, gives off one or two
branches to the patagium. The branch has been termed
the pectoralis propatagialis. There are either two separate
muscles split off from the surface of the pectoral (as in Nisus);
the tendon of one going to the tendon of the tensor patagii
longus, that of the other to the tensor patagii brevis; or
(Podargus) there is but one muscle which divides into two
tendons; or the origins of the two tendons are separate, one
of them commencing with a special muscle, the other arising
as a tendon from the surface of the pectoralis ; or both may
be tendinous in origin. Finally, there is in tinamous and
gallinaceous birds (some) a special 'propatagialis posticus,'
joining with its tendon that of the other muscle. The
pectoralis abdominalis, totally absent in nearly all ratites, in
storks, various hawks, &c., is divisible into two parts, of
which one or other is sometimes wanting. The pars posterior
springs from the pelvis and adjacent fasciæ; it ends in front
freely or comes into more or less close relations with the pars
anterior. In Anseres, for example, the two form one con-
tinuous band of muscle, their boundaries being simply marked
by a slight tendinous inscription. The pars anterior arises
from the skin close to the termination of the last, or is, as
already mentioned, continuous with it; it generally ends upon
the humerus, near or in common with the insertion of the
main part of the pectoral. In a few birds (quite remote
from each other in the system, Pelėčanus, Chaundi, Cathartes)
the terminal tendon is lost in the axillary region; a more
remarkable modification, possibly of classificatory importance,
is described later in Crypturus. In a variety of birds there
is a slip from this muscle to the metapatagium.
Latissimus Dorsi.—This muscle is divided by FÜRBRIN-
GER into three sections-
(1) L. d. anterior.
(2) L. di posterior.
(3) L. d. metapatagialis and dorso-cutaneus.
The first-named muscle is totally wanting in Apteryx and
LO
80
STRUCTURE AND CLASSIFICATION OF BIRDS
Alcedo bengalensis. It arises in other birds from the spinal
processes of a varying number of cervical and dorsal vertebræ.
The narrowest area of origin is seen in Alcedo, Macrochires,
and various passerines, where it embraces at most a single
vertebra. In other birds it may arise from as many as four
and a half vertebræ. The broad fleshy or tendinous, or
partly fleshy and partly tendinous, insertion varies in width.
: The second division is entirely wanting in Otis, Pterocles,
many passerines, &c. It arises from the spinous processes of
posterior dorsal vertebra, ilium, and even adjacent ribs. Its
origin is usually widely separated from that of anterior ; but
there are various intermediate conditions which culminate in
the cuckoos, Macrochires, and some other birds, where the
two muscles form one, with, however (save in Cypselus),
separate insertions. The insertion of this muscle is by a
slender tendon in front of that of the latissimus dorsi
anterior.
The latissimi dorsi metapatagialis and dorso-cutaneus
are two slips running to the metapatagium and the neck
region of the skin respectively. They are not often both
present, but are in Apteryx, Charadridæ, Alcidæ, and some
gallinaceous birds. They are both absent in ratites (excl.
Apteryx), Macrochires, Colii, Bucerotidæ, &c. The dorso-
cutaneus is the rarest, and apart from the instances mentioned
is found only in the Cracidæ, piciform birds, and passerines.
Cucullaris.--This is an extensive muscle occupying the
greater part of the neck. The only muscle superficial to it
is the sphinctor colli. It has two main divisions. The
pars cranialis arises from the region of the occipital and the
squamosal; in many birds of the most diverse orders) a
branch is given off from this (the dorso-cutaneus), which
ends on the back below the spinal pterylon, whose feathers
it raises. The main part of the muscle ends upon the
clavicle, or sternum, or ligaments in the neighbourhood.
In some birds a part of the fibres . end upon the fascia
covering the pectoralis primus, and in those with a crop
some of the deeper fibres come into relation with that
i Not in 4. ispida.
.
ILI
MUSCLES OF THE FORE LIMB
ta
organ, forming a levator ingluviei. A portion of the cucullaris
also directs itself towards the patagium, and in most Passeres
and in parrots, Pici, and Upupa forms a special cucullaris
propatagialis, joining the tensor longus tendon. The pars
cervicalis of the cucullaris arises from the dorsal edge of the
neck, and is inserted near or in common with the other part.
In many birds (e.g. Anseres) a slip is given off from this
which supplies the humeral pterylon. It is termed the cucul-
làris dorso-cutaneus.
Rhomboideus Externus.—This muscle arises tendinously,
the width of the tendinous part being about the same as
that of the muscular part, from the last cervical and from
the dorsal vertebræ ; it is inserted fleshily along the whole
length of the scapula. The muscle varies but slightly; the
origin is more or less extensive, and the vertebræ from
which it arises are not always the same. Its insertion is
not always limited to the scapula, but sometimes extends on
to the furcula. In Casuarius and Apteryx the muscle arises
from the ribs.
:: Rhomboideus Profundus.—This muscle also arises ten-
dinously from the neural spines of the dorsal vertebræ, or
from both dorsal and cervical. Its origin sometimes extends
as far back as to the ilium. It is inserted into the
scapula below the last. In Casuarius and Apteryx this
muscle arises from the ribs. The rhomboideus profundus is
occasionally divided into two distinct parts; in Megalæma
there are three distinct divisions.
Serratus Superficialis.—This muscle is divided by FÜR-
BRINGER into three parts, of which two are always present,
while the third is sometimes absent. This is the pars
métapatagialis. The pars anterior arises from one or more
ribs on the boundary line between the cervical and dorsal series.
It is attached to the scapula along the ventral border, but, quite
exceptionally, in Rhea on to the dorsal border. The pars
posterior springs from a varying number of dorsal ribs, and
in several birds (e.g. Rhamphastos) it, with the pars anterior,
which can hardly be separated as a distinct muscle, springs
from a considerable number of ribs-five in the case referred to.
LE
LU
82
STRUCTURE AND CLASSIFICATION OF BIRDS
It has generally a broadish insertion on to the scapula, but
in Meiglyptes, many Passeres, &c., it is attached merely to the
extremity of that bone. The pars metapatagialis is absent
in ratites (except Apteryx), humming birds, and a few others.
It springs from 1-4 ribs, and is inserted on to the meta-
patagium.
Serratus Profundus.—This muscle is highly developed
in Struthio and Casuarius, less so in other struthious birds
and in the Carinates. It arises from a variable number of
cervical and dorsal ribs, and it passes backwards in the
contrary direction, therefore, to the serratus superficialis) to
be inserted on to the scapula.
Patagialis.!—This muscle, concerned with the folding of
the patagial membrane, is present in all birds except the
struthious. It arises from the clavicle and from the tip of
the scapula, is sometimes divided into two muscles from the
start, and sometimes arises as a single muscle, which
immediately divides into two tendons, the tensor patagii
longus and the tensor patagii brevis. Exceptionally the
former may be absent. In a specimen of Crex pratensis
the representative of tensor patagii longus was found by
GARROD to be simply the biceps slip, a muscle that will be
treated of presently.. The size and importance of this
muscle vary considerably; it is largest in the parrots,
where, indeed, it is uncertain whether a part of the deltoid
has not been converted to a similar function. This matter,
however, is dealt with under the description of that family.
The tensor patagii longus always ends in a single tendon
which runs along the anterior margin of the patagium and is
inserted on to the metacarpal. It is usual for the middle
part of this tendon to be of a more fibroid character and of
a yellowish colour, contrasting with the steely and typically
tendinous aspect of the other tendons arising from the
tensores. Very commonly the entire tensor muscle is.
ralis, and sometimes there is a separate slip to each of the
! G. BUCHET, ^ Première Note sur l'Appareil Tenseur,' &c., C. R. Soc. Biol..
1988, p. 328.
MUSCLES OF THE FORE LIMB
83
two tensores. It is also very general for one of the two
tendons, or for both before their division, to be attached by a
tendinous slip to the deltoid crest of the humerus. The
tensores patagii are of considerable use in classification.
But it must be admitted that they are apt to vary greatly
from genus to genus. The variations chiefly concern the
more or less complicated condition of the tendons of the
brevis. The simplest condition is seen, e.g., in Rhamphastos
Cuvieri, where the tendon is single and is attached below to
the tendon of origin of the extensor metacarpi radialis.
A further degree of complication is seen in, e.g., a cuckoo,
where the single tendon gives off, near to the fore arm, a slip
running obliquely wristwards, which is attached to the tendon
of the extensor metacarpi radialis. In the limicolous birds the
main tendon is usually divided from the first into two, of
which the anterior has the wristward slip, already referred
to; in those birds and many others there is the further
complication of a band of tendinous fibres which arise at the
junction of the wristward slip with the fore arm, and pass
obliquely forwards and upwards to be inserted on to the
tendon of the longus. This slip is termed, in the following
pages, the 'patagial fan ;' it is frequently of a fanlike form.
The tendon of the tensor patagii brevis has not always the
regular form that it has in the types that have been already
selected for illustration. In the tinamou, Rhynchotus, for
instance, the tendon is a diffuse fascia spreading out over
the greater part of the patagial membrane; in other birds,
e.g. storks, it is a broad, rather diffuse band, as a rule with
a thicker edge or edges. A peculiar condition of the
tendons of the brevis characterises the auks, some gulls, and
at least one limicolous bird. In them (see below) one or
two delicate tendons arise from the longus tendon near to
the insertion thereon of the patagial fan, and run obliquely
backwards and downwards to be attached on to the dorsal
surface of the fore arm—the reverse side, that is to say, to
that to which the other tendons which together make up
the tensor patagii brevis are attached.
In some birds, e.g. certain passerines, the tendon of the
( 2
84
STRUCTURE AND CLASSIFICATION OF BIRDS
tensor longus is reinforced by a muscular slip ending in a
tendon which is derived from the cucullaris muscle. Another
muscle which is also related to the patagialis in an analogous
way has been termed the 'biceps slip' (9.v.) :
Anconaus Longus. This muscle arises from the neck of
the scapula alone, by a head which is entirely tendinous or
partly muscular, or in addition from the edge of the scapula, a
little further away from its junction with the coracoid, by a
tendinous head. It is inserted by a broad tendon on to the

mo
T.P.L.
-
Bi
-7.P.B
ny
N
CC
YO
.
.
.
.
C
M
..
.
E.C.R.
py
C
maneno na may
Y
N
.
1
1
.
IN
C
ULTER
1
AV:
.
*
i
.
.
.
-
.
.
.
.
Fig. 49.–TENSORES PATAGII OF Phoenicopterus.
T.P.L, tensor patagii loogus; T.P.B, tensor patagii brevis; Bi, biceps
slip; E.C.R, extensor carpi radialis. (After WELDOX.)
elbow joint. Sometimes there is an accessory head from
the humerus, which in this case arises, as a rule, in common
with the tendon of insertion of the posterior latissimus
dorsi. In Palamedea this head is double, the two halves
being united by cross tendinous threads. On the whole the
humeral head is characteristic of GARROD's Homalogonatæ
and not of the Anomalogonatæ ; but there are exceptions on
both sides. The breadth of the humeral head varies greatly;
it is sometimes reduced to a thin thread.
MUSCLES OF THE FORE LIMB
85:
Triceps. This muscle springs from the greater part of
the humerus fleshily by two heads, of which one-that from
the tuberculum minus—is often tendinous. The name
triceps, be it observed, has been given to the muscle on the
understanding that the last-described muscle is a part of it.
Their tendons of insertion join.
. Expansor Secundariorum._This extraordinary muscle
appears to be partly a skin and partly a skeletal muscle.
A bundle of non-striated fibres arises near the secondary
feathers of the arm and ends in a tendon. This is occa-
sionally reinforced by a band of striated fibres arising
from beginning of ulna. The long tendon is inserted in
various ways. The typical condition (termed by GARROD
ciconiine?) is for it to be inserted into the middle of a liga-
ment running from the scapulo-coracoid to the sterno-
coracoid articulation. Other modifications occur among the
gallinaceous birds (9.v.), &c. The muscle is totally absent
in Struthiones, Sphenisci, Alcæ, Psittaci, the majority of Pico-
Passeres, and in a few species of groups where it is usually
present.
Sterno-coracoideus.—This muscle, wanting only in the
Macrochires, runs from the anterior lateral border of the
sternum to the adjoining region of the coracoid. The muscle
shows every stage between a single muscle and a completely
double one. It is double, for example, in Casuarius. In
one sterno-coracoid, it is the homologue (according to FÜR-
BRINGER) of the deeper section of the double muscle.
Scapulo-humeralis Anterior.—Runs from the beginning
of the post-glenoidal region of the scapula to the beginning
of the dorsal surface of the humerus. It is a muscle which is
frequently absent. FÜRBRINGER failed to find it in Struthiones,
Sphenisci, Fregata, Chauna, Columbæ, Pterocles, Chunga,
Bucorvus, &c.
Scapulo-humeralis Posterior.--Contrary to the last this
is a large muscle and is never absent. It arises from the
I GARROD, “On the Anatomy of Chauna derbiana,' &c., P. Z. $. 1876
p. 193, &c. .
86
STRUCTURE AND CLASSIFICATION OF BIRDS
hinder part of the scapula and runs to the humerus, where
it is inserted on to the tuberculum mediale.
Coraco-brachialis Externus. This muscle, which is.
relatively larger in the struthious birds, runs from the
coracoid to the beginning of the planum bicipitale' of the
humerus, where it is generally covered by the tendon of the
biceps. It is noteworthy that among carinate birds this
muscle is largest in the tinamous, which thus approach the
ostrich tribe. It is most reduced in the Passeres, in some
of which, indeed, it has actually disappeared.
Coraco-brachialis Internus.— Springs from the coracoid
and often from neighbouring parts of sternum. It is inserted
on to the median tubercle of the humerus.
Pectoralis II.-This muscle arises from the ventral
surface of the sternum, from the coracoid, and from
the coraco-clavicular membrane. It is inserted by a long
tendon of attachment to the lateral tubercle of the humerus.
The muscle is small in ratites, large in carinates.
Deltoides Major.–Arises from the acromion and the
dorsal part of the clavicle, and is inserted on to the deltoid
crest of the humerus. The muscle and the length of its
attachment vary much in size. It is large in Accipitres,
Passeres, &c., small in Alcæ, Psittaci, &c. It appears, indeed,
to be absent in Psittacula.
Deltoides Minor.—This is a small muscle passing from
the neighbourhood of the foramen triosseum. It is absent in
Phaëthornis and occasionally) in Cypselus. It is also
absent in Struthiones.
Biceps. This muscle consists typically of two heads, as
its name denotes. The longer of these arises from the
coracoid by a long tendon. The second head arises also
tendinously from the head of the humerus. The insertion
of the muscle is double, on to the radius and the ulna. The
division commences at a varying distance from the actual
insertion.
In the penguins this muscle is totally absent. In
Colymbus, Pelecanoides, Thalassiarche, and other petrels, in
some Alcidæ, the coracoid head alone is present, the humeral
MUSCLES OF THE FORE LIMB
87
:
21
I
head being in some of these birds entirely diverted to form
the biceps slip to the patagialis (q.v.) The coracoidal head,
when it exists alone, may be divided into two quite separate
muscles, uniting only at their very origin. This is the case
with certain Alcidæ. This division of the coracoidal half of
the muscle also exists in the Laridæ and in certain Limicolæ,
where there is a humeral head present also. In the Stega-
nopodes both heads are present, but the humeral head after
its attachment to humerus is continued on to the coracoid.
A trace of this arrangement is apparently left in some birds
(e.g. Porphyrio), where, though the humeral head arises from
the humerus only, a ligament passes on from that part to
the coracoid.
Brachialis Inferior.—A flat fleshy muscle arising from
the distal part of the humerus, and inserted upon the ulna.
In the penguins (where the biceps is absent) this muscle is
particularly large, and is inserted on to the radius.
Pronator Sublimis.--This muscle springs tendinously from
the inner condyle of the humerus and is inserted fleshily,
and for a varying distance in various birds, upon the second
third to second eighth of the radius.
Pronator Profundus.--This muscle lies deep of the last,
but has a similar origin and insertion. In the Ratitæ this
muscle and the last form a single muscle.
Entepicondylo-ulnaris.—This muscle, found apparently
only in Galli and Tinami, arises in common with the pro-
nator profundus, and is inserted on to the ulna.
Ectepicondylo-radialis.-This muscle arises tendinously
from the outer condyle of the humerus and is inserted
fleshily on to the radius. It appears to be wanting in the
penguins, and to be largest in the Galli.
Ectepicondylo-ulnaris.--This muscle arises from the
outer condyle of the humerus, and is inserted similarly to
the last upon the ulna. Its insertion is fleshy, and in
Palamedea it is larger than the last.
Flexor Carpi Ulnaris.-This arises from the inner con-
dyle of the humerus by a strong tendon, in which there is
a well-marked sesamoid ; it runs down the inner side of the
CU U
88
STRUCTURE AND CLASSIFICATION OF BIRDS:
ulna to be inserted on to the great tuberosity of the ulnar
çarpal bone. A thin muscle arising from it passes into a
tendon which is connected with the secondary feathers.
The above refers to Palamedea. In penguins the entire
muscle is represented by a tendon only.
Extensor Digitorum Communis. ---Arises from the external
condyle of humerus. It splits on the hand into two tendons,
of which one is inserted on to the basis of the first phalanx
of digit I., the other on to the corresponding phalanx of
digit II. In Struthio the first of the two tendons is wanting.
In the penguins the muscle is represented only by a tendon
which is inserted on to the outer side of metacarpale II. and
on to the basis of the first phalanx of that digit..
Extensor Longus Pollicis.-This muscle arises from the
proximal region of both radius and ulna. The common
tendon is inserted on to the origin of metacarpale I.
Extensor Indicis Longus.—This muscle is two-headed.
The longer head arises from the radius from its miadle two-
thirds, but sometimes also receives a few fibres from the
ulna; the second much shorter head springs either from the
distal end of the radius or from the os carpi radiale, or
finally from the basis of metacarpale II.; the united tendons
are inserted on to the head of the first and the basis of the
second phalanx of digit II. The second head is absent in
Fulica and in some other birds.
Interosseus Dorsalis.--This muscle arises fleshily from
the opposed surfaces of metacarpals II. and III. The
common tendon is inserted on to the base of the second
phalanx of the second digit.
Interosseus Palmaris.-Has an origin from the same
metacarpals as the last and is inserted on to the first phalanx
of digit II.
Ülni-metacarpalis Ventralis. - It arises fleshily from the
radial face of the last quarter of the ulna, and is inserted on
to the head of the first metacarpal.
Ulni-metacarpalis Dorsalis.—This springs by a tendon
from the distal region of the ulna, and has an insertion upon
the third metacarpal.
MUSCLES OF THE FORE LIMB
89
:
7
Extensor Metacarpi. Ulnaris.—Springs from the external
condyle of the humerus. There is generally a second head,
which, instead of being tendinous, is fleshy and rises from
the humerus a little below the first head. The tendons in
which the two end do not join until a little before their
insertion on to the base of the metacarpal of digit I. The
degree of separation of the two heads differs considerably.
In the penguins only one head is present.
Flexor Digitorum Sublimis. From the internal condyle
of humerus to os carpi ulnare is a strong aponeurotic fascia,
from the distal end of which springs the muscle in question,
to be inserted on to phalanx I. of digit II. In Palamedea Mr.
MITCHELL and I traced the tendon to the base of the second
phalanx of the same digit. In Psittacus and Columba the
tendon has the same extension. In Struthio the muscle is
entirely absent.
Flexor Digitorum Profundus.-This springs from the
middle and proximal third of the ulna, and is inserted on to
the basis of the second phalanx of the second digit. In
Corviis, &c., the muscle is two-headed, the two heads being
separated by the insertion of the brachialis internus. In
other birds the extent of the origin varies.
· Abductor Indicis.-From metacarpal II. to basis of phalanx
I. of digit II. In Palamedea it also arises from the flexor
pollicis.
Flexor Pollicis.-From metacarpal I. to thumb phalanx.
In Palamedea its fleshy belly gives rise to a slip which passes
to the abductor indicis.
Adductor Pollicis.---In Palamedea it arises from the meta-
carpal just beyond the articulation of the thumb; it ends
in the ala spuria and not on the thumb bone. In some
Extensor Pollicis Brevis.—This muscle arises fleshily from
the second metacarpal. It is inserted on to the phalanx of
the-thumb.
Abductor Pollicis.-This muscle arises from metacarpal I.
and passes to phalanx of same digit.
90
STRUCTURE AND CLASSIFICATION OF BIRDS
Flexor Digiti III.–Arises from metacarpal III. and is
inserted on to basis of phalanx I. of same digit..
Flexor Metacarpi Radialis. This muscle arises from the
outer condyle and is inserted on to the ulnar border of
metacarpal II. or on to the beginning of metacarpal III.
Muscles of the Hind Limb
Sartorius. This is a broad strap-shaped muscle arising
from the ilium and from the fascia covering the glutæus
maximus; it is inserted on to the ligament containing the
patella, and on to the crest of the tibia. The muscle has an
origin which sometimes extends further forwards, and is
then overlapped by the latissimus dorsi. Sometimes, on
the other hand, its insertion moves further back. In
Phoenicopterus the muscle is divided into three distinct
portions. -
Gluteus Maximus. 2_ This often large muscle was used
by GARROD 3 in his muscular classificatory scheme, and at
first termed the tensor fasciæ. It has an origin which is
sometimes entirely in front of the acetabulum, and some-
times extends behind it. It arises tendinously from the
fascia covering the glutæus medius, and from the ridge of
the ilium; its insertion is tendinous on to fascia covering
thigh.
Glutæus Anterior. 4—This muscle arises from the ridge of
the ilium below the last, by which it is entirely covered; it
is inserted by a tendon on to the outer face of the thigh.
The most remarkable modification which this muscle under-
goes is its entire conversion into tendon in Bucorvus, &c.,
in which birds it comes to be merely a thigh ligament.
Gluteus Medius:5_-This arises fleshily from the ilium,
and is inserted by a short strong tendon on to head of
femur.
1. Ilio-tibialis internus' (GADOW). ? • Ilio-tibialis externus' (GADOW).
3. On certain Muscles of the Thigh of Birds,' &c., P. Z. S. 1873, p. 626, and
1874, p. 111.
4 Ilio-femoralis externus' (Gadow).
5 Ilio-trochantericus medius et posterior' (GADOW).
MUSCLES OF THE HIND LIMB
91
Gluteus Quartus. —This is a small muscle lying at its
insertion between that just described and that about to be
described.
Gluteus Minimus.2—This muscle is also small, and
UULILLO

GLUTE
GLUT.4.-es
A
NO
GLUT. 3
GLUT.PANT-
& CRUREUS
SEMITENDO
nn
III
MPIUTTON
1
.
GTE
A
OBO INTERN.
YA
VASTS & CRU
.
FEMUR.
TERRELL
na
VITY
LOS
Vid
PS
.
.
....
.
OBD.INFO
:
..
....
.
.
AMBIENS
107
.
V
.
.
.
.
.
NO
V
2
.
.
BICEPS
FEMO CAUO
YA
.
11
.
Wo0rb
01.id
V
.
.
1
.
.
.
AN
LONGE HALLE
.
COXOX
www
I
I
www
1
A-
A
ON
DA
2
ca
f
.
JMY
A
TIBIA
S
77
FLEX. 2
o! I.
_FLEXOR 1.0F HIL DIGIT.
.
FLEX
of I,
FLEX ) OP
u
U
FLEX? 2
of II.
FLEX, COMM
FIG. 50.—MUSCLES OF LEG OF Palamedea, OUTER VIEW (AFTER BEDDARI)
AND MITCHELL).
arising from the ilium is inserted next to the last on to the
neck of the femur.
Pectineus. 3- This is a smallish muscle arising below the
I 'Ilio-trochantericus medius et posterior ’ (Gadow).
? • Ilio-trochantericus anterior' (GADOW).
3. Ilio-femoralis internus' (GADOW).
92
STRUCTURE AND CLASSIFICATION OF BIRDS
origin of the glutæus quartus and inserted on to the inner
face of the femur below the head.
Vastus Externus.!—This arises fleshily along the greater
part of the outer side of the shaft of the femur; it is fused
with the crureus in front, and ends with it upon the patellar
ligament.
Crureus.!—This is tendinous on the outer surface at its
origin from the neck of the femur; it also arises from a
considerable part of the shaft of the femur and is inserted
as has already been described.
Vastus Internus.l.-- This arises from the inner surface of
the shaft of the femur and is inserted on to the tibia along
with the tibial insertion of the sartorius.
Obturator Externus. 2- This is a small deep-lying muscle,
which arises from the ischium or the ilium, or even partly
from the pubis ; it is inserted on to the trochanter.
Obturator Internus.3—This muscle arises from the mem-
brana obturatoria and from the ischium. It is inserted on
to head of femur. GARROD 4 laid some classificatory stress
upon the shape of this muscle, oval or triangular.
Gemellus.5—This is a small fleshy muscle, double or
single, surrounding the tendon of insertion of the last.
Semitendinosus.6-In Palamedea this muscle arises fleshily
from the ilium behind the biceps; it is half an inch broad,
and, after being joined by the small accessory which springs
from the femur near its distal end, sends a flat tendinous
slip to the semimembranosus. The rest of the tendon of the
muscle joins the middle head of the gastrocnemius. The
muscle shows considerable variations in its attachments and
size. It is completely absent in the owls, hawks, and swifts.
The accessory head is absent in kingfishers, many Stegano-
podes, Colymbus, &c.
1. Femori-tibialis' (GADOW). ? «Ischio-femoralis' (GADOW).
3 Obturator' (GADOW).
1. On the Anatomy of Chauna derbiana,' &c., P. Z. S. 1876, p. 195.
5. Accessorii musculi obturatoris' (GADOW).
6 'Caud-ilio-flexorius' (GADOW).
MUSCLES OF THE HIND LIMB
2
.0
Femorocaudal."This is another of the variable muscles
of the thigh. Typically the muscle is two-headed, one head
arising from the transverse processes of the caudal vertebræ,
the other (termed by GARROD accessory femorocaudal) from
the ilium. The two are inserted together upon the flexor
side of the femur, as a rule by a longish tendon.
The variations culminate in the entire absence of the
muscle, which occurs in Chunga Burmeisteri and Leptoptilus.
In some species--for example, in most Passeres and picarian
birds--the caudal portion is alone present. In others—e.g.in
Serpentarius, Otis, Phænicopterus, the iliac portion is alone
present.
Biceps Femoris.2_-This muscle is covered externally by
the glutæus maximus where this is present; otherwise it is
the most superficial of the flexors of the leg. It arises from
the postacetabular region of the ilium, and ends in a strong,
generally round, tendon, which passes through a sling of
tendon which is derived from the femur independently, and
from the same bone in common with one of the heads of the
gastrocnemius, to be inserted on to the fibula. The principal
variations of the muscle concern its more or less extensive
origin. It has never been known to be absent. In Cory-
thaix GADOW states that it is double. In the ostrich and in
the ducks and swans there is the usual sling, but before
entering the sling the biceps gives off a branch, which joins
one of the heads of the gastrocnemius. In Fregata and in
some swifts quite exceptionally the sling is totally absent,
but the muscle has the usual insertion. In certain auks the
muscle gives off, before entering the biceps sling, a branch
to the thigh superficially. In Podica senegalensis the
muscle divides into three branches. The first of these has
a considerable superficial attachment to the outside of the
leg; the second is attached to the fibula below the attach-
ment of the third insertion, which is the normal one, through
a sling. In Heliornis only the first and third of these are
present.
i Caud-ilio-femoralis' (GADOW). . ? Ilio-fibularis' (GADOW).
.
/
94
STRUCTURE AND CLASSIFICATION OF BIRDS
Semimembranosus. — Arises from the ischium, sometimes
trenching a little upon the pubis. It is inserted upon the
tibia. The variations which it shows are mainly of size.
In Phænicopterus it is two-headed, and in certain Falconidæ

.
.
SARTORIUS
..
VAST
.
.
INTERN,
.
.
os
-
4
www
W1111111
BICEP
X
:
TI
.
1
UN
mond
w
Vio
1
..
U
www
.
.
.
|
.
.
......
.
.
.
..
.
.
..
.
..
.
.
w
ww.
ch
.
V
.
wewe
SOLLUS
EINIMUMA
.
FLEXR HALLS
FLEXSPERPORANS.
Fig. 51.-LEG MUSCLES OF Palamedea, INNER VIEW (ATTER BEDDARD
AND MITCHELL), ILLUSTRATING BICEPS AND ITS SLING.
completely double. It is often inserted in common with
the semitendinosus.
Adductors.2—These are, as a rule, two broad, flat, fleshy
bands, which arise from the pubis, and from the ischium,
and are inserted upon the inner edge of the femur. The
separation between the two parts is less in some birds than
'Ischio-flexorius' (GADOW).
? • Pub-ischio-femoralis ' (GADow).
MUSCLES OF THE HIND LIMB
95
IUC
in others. There is also occasionally (e.g. hornbills) an
additional attachment to the gastrocnemius.
Ambiens.—This muscle, as is well known, is not present
in all birds. Though the late Mr. GARROD used it largely
in his scheme of classification, its mere presence or absence
is not an absolute guide to the systematic rank of the bird.
Broadly speaking, it is present in all the birds which
GARROD called homalogonatous, or normal-kneed, and

ZOO
Oxu
mo
OX
.
e.
.
..
.
W
.
.
.
.
..
.
ti
.
..
.
V
gastr.
.
WWW
..
.
W
...
NOWY
LANTAI
hu
net
.
.
Femur
want
.
1
ttttt
.
..
N
W
- SE
.
11
"
serta
mo
anneer
1
MON
ANEX
Biceps
.
mai
error
>
,
..
WA
.
...
w
mult
S
Sina WUTUA
SYLWww
ter"
*
.
.
wwwwww
ANO
TIPE
into the
A
01111MMIT
Amo
HEPS
T
DOW
ML
NOTES
TI
.
UMA
White
....
..
N11
D
16.
11
**
mit
pini!
Other
.
ANA
NUMA
.
ART
wertuluinimum
C
meget
.
1
.
AX
:
r
yang perempuan
entwininni ti
PE
.
..
W
t.ee
17
Women
meIn
ment
ullimin
..tif
y
creminuto
3 4
fibula
Fig. 52.-LEG MUSCLES OF Balearica (AFTER MITCHELL). THE
AMBIENS TENDON IS CUT.
1, flexor longus hallucis ; 2-4, flexores perforati ; 2', 3' flexores perforati et perforantes.
it is absent in all the birds which were termed by him
anomalogonatous, or abnormal-kneed. But there are excep-
tions, at any rate on one side. Thus while the muscle is
present in the storks generally it is absent from the nearly
related herons, and, indeed, is absent in three storks, Xeno-
whynchus, Abdimia, and Dissura. When the muscle is
present it has as a rule the relations described above; but
in a few birds it does not reach beyond the knee, thus
showing, perhaps, an incipient disappearance. The import-
Vu
UUUU
.96
STRUCTURE AND CLASSIFICATION OF BIRDS
ance of this muscle in classification has been much increased
by MITCHELL's interesting paper upon its exact relations
to the flexors of the leg in a series of birds. He hàs shown
that in Balearica chrysopelargus the mass of muscle which
forms the flexor perforatus arises from three distinct heads;
one of these is, in common with the flexor longus hallucis,
from the intercondylar notch of the femur; the second is
VID GLUT. 2.:

LUT.3
BICEPS
SART.
I..
M
VAST.
UCRUR.
- and
CRUR.
.
.
00--GLUT. ANT.
Veget
---OBD. INT.
B-OBD. EXT.
ADD.
FEM.CAUD. and ACC.F.C.
SEMI-MEM.
Ontd
www
.
e. ii
.
.
.
1. SEMI-TEI
FIB.
KAMBIENS
II.2.
!
GASTROCN. 2.
...TIBIA
II
IY
TL
i
11
PER.2.
FLEX. COM.
FIG. 53.---LEG MUSCLES OF Opisthocomus (AFTER MITCHELL).
II-IV, flexores perforati.
UU
from the outer condyle of the same bone; the third is from
the tendon of the ambiens. This tendon divides into three,
one for each of the three divisions of the flexor perforatus.
The arrangement will be obvious from the accompanying
cut. Apart from slight differences in detail the same
arrangement was found to hold good for a few other birds
provided with an ambiens.
1.On the Perforated Flexor Muscles in some Birds, P. Z. S. 1834, p. 495.
GY
1
MUSCLES OF THE HIND LIMB
97
7
In Nycticorax Gardeni, which has no ambiens, there is a
difference in the origin of the flexors in question which is of
great interest. The two origins from the femur are as in the
crane. But there being no ambiens there can be no origin
from that muscle. Nevertheless the third head of the
flexors is present in the shape (see fig. 53) of a broad ten-
dinous band arising from the fibula, which soon divides into
the three tendons to the three muscles, precisely as does the
tendon of the ambiens. This is highly suggestive of the
rudiment of an ambiens, a suggestion which is confirmed on
referring to a specimen of Opisthocomus without a fully de-
veloped ambiens (fig. 53). And as the herons are birds which
are presumed to be really homalogonatous birds, though
they have lost the ambiens, the fact is of additional interest;
particularly is this so when we compare the conditions
obtaining in Nycticorax with those which characterise
Corvus, a clearly anomalogonatous bird, none of whose near
relatives possess an ambiens. In Corvus capellanus it was
discovered that the flexors usually connected with the am-
biens, or with its rudiment, had no origin from the fibula
at all, and arose by only a single head from the femur. The
same was practically the case with Bubo maximus, only
that both femoral heads were present. Now the owls,
formerly relegated to the Accipitres, are more generally
looked upon as related to the picarian birds, forming, in
fact, a section of the anomalogonatæ of GARROD. The state
of their ambiens is entirely confirmatory of this placing.
We have some evidence, therefore, that there are degrees in
the disappearance of the ambiens, which, so far as the few
types that have been examined enable us to say, distinctly
support the division of birds into the two great divisions of
GARROD.
Peroneus Superficialis.—Confined as a rule to the tibia
in its origin, this muscle sometimes springs also from the
fibula. The tendon of insertion, after giving off a branch
to the tarsus, becomes attached to the tendon of the flexor
perforatus digiti III. This muscle is occasionally completely
absent; this is the case with various Picopasseres, owls, &c.
98
STRUCTURE AND CLASSIFICATION OF BIRDS
In Podiceps, according to GADOW, there is no branch to the
flexor tendon, the tendon of insertion ending at the ankle.
Peroneus Profundus.--This muscle arises from the lower
part of the tibia, and is inserted on to the outer side of the
ankle. It is completely absent in such birds as Ciconia,
Otis, &c.
Gastrocnemius.—This great muscle occupies the greater
part of the back of the leg. It has three heads, of which
the outer arises from the outer condyle of the femur, and
from the ligament which supports the insertion of the
biceps; the inner head springs from the inner side of the
head and neck of the tibia ; the middle head is confused at its
origin with the insertion of the accessory femoro-caudal.
This middle head appears to be wanting in Cypselus. It is
inserted by a strong tendon to the tarso-metatarsus, and
also, dividing, to the phalanges of the toes.
Popliteus.--This muscle passes between the tibia and
the fibula in most birds, but has been found to be sometimes
absent (e.g. Picus, &c.)
Tibialis Anticus. This muscle arises by two distinct
heads. The first is entirely tendinous, and is from the
external condyle of the femur. It forms a long and strong
ligament, which runs over the knee; the second head is
fleshy, and is from the front part of the head of the tibia.
Its long tendon of insertion is attached to the metatarsal.
In certain birds (Chrysotis, Podargus, and owls) the tendon
and even a portion of the muscle are double.
Ectensor Digitorum Communis.- This muscle arises gene-
rally from the front part of the tibia only, but sometimes its
fibres of origin stray on to the patella and on to the fibula.
The divisions of the tendon of the muscle are usually inserted
on to several phalanges of the toes, which they supply. It
is remarkable that the parrots are the only birds in which this
muscle supplies the hallux as well as the other toes; it is,
therefore, in them, as GADOW remarks, truly an extensor
communis. In other birds digits I., III., IV. (when present)
are the only toes supplied. The common tendon divides in
various ways; in Grus virgo the tendon divides into two,
MUSCLES OF THE HIND LIMB
99
ICU UU
and each of these again divides; there are thus four tendons,
of which the two middle ones supply the third toe. In
Ptilonorhynchus violaceus the tendon first gives off a branch
to the second toe, and then divides for the third and fourth.
In Rhamphastos carinatus all three branches are given off at
the same level. In Pharomacrus mocinno the extensor sup-
plies only the two middle digits. In Scopus there is a slight
variation of what is found in Grus, Nothura, &c. The
tendon divides into three, and the middle one again divides
into two, both of which latter supply the middle digit.
The superficial flexors of the foot consist of—
Flexor Perforatus et Perforans Indicis (fig. 51).–Arising
from the outer condyle of the femur, and from the septum
between itself and adjacent muscles ; its tendon is inserted
on to base of second phalanx of its digit.
Flexor Perforatus et Perforans Medii.--Has two heads
of origin, one as in last, the other from fibula. Its tendon
perforates that of flexor perforatus of the same digit, and is
perforated by flexor profundus; it is inserted on to base of
second phalanx (in Palameded, third in Ciconic) of its
digits.
Flexor Perforatus. – This muscle (see figs. 52, 53) arises
from two heads, an inner head from the intercondylar notch
and an outer head from the outer condyle of the femur. As
will be seen from the annexed cuts, those portions of the
muscle which supply digits III. and IV. have slips from both
heads, but not that which supplies digit II. These muscles
also arise either from the ambiens or from the fibula, as has
been explained above under the description of the ambiens.
The tendon to digit II. is inserted at the base of the first
phalanx, that to digit III. is usually joined by à vinculum
(absent in Opisthocomus, Asio otus, and Rhytidiceros plicatus)
to tendon of flexor perforatus et perforans medii, and is
inserted on to base of second phalanx of digit III. The third
tendon has four slips of insertion, on to four proximal
phalanges of digit IV. The descriptions of the insertion of
these tendons applies to Ciconia nigru. There are varia-
tions.
19199
HI 2
100
STRUCTURE AND CLASSIFICATION OF BIRDS
Flexor Profundus.-Arises from nearly whole hinder
surface of tibia and fibula, and sometimes also by a head
from the outer condyle of femur.
Flexor Hallucis.--Arises by a single head, or by two
heads, from the outer, condyle of femur and from inter-
condylar region.
The tendons of the two last-described muscles are con-


.
N
VZUNU
22
I
RE
Si
VIS
12
*
VA
MA
.
.
.
88
KW
ننمل
II.
Fig. 54.--Gallus bankiva (AFTER
GARROD).
FIG. 55.-Apteryx Mantelli (AFTER
GARROD).
nected with each other in various ways, which have been
described and illustrated by Mr. GARROD. In using his
figures I accept the seven types admitted by Dr. GADOW.2
(1) In gallinaceous birds, pigeons, parrots, storks, &c., the
tendons cross, and are united by a simple vinculum (fig. 54).
1. On the Disposition of the Deep Plantar Tendons in different Birds,"
P.Z. S. 1875, p. 339.
? In Newton's Dictionary of Birds, p. 617.
MUSCLES OF THE HIND LIMB
101
(2) In Apteryx, &c., the vinculum is very strong, and
forms the direct continuation of the tendon of the flexor.
hallucis; the tendon to the hallux has the appearance of
being a branch of this (fig. 55).
(3) In many Accipitres the flexor hallucis divides into two
parts at the lower end of metatarsus ; one of these goes to hal-
lux, the other blends with the branch of the flexor communis


AM
**
SA
SV
FIG. 56.-Tinnunculus
alaridarius (AFTER GARROD).
Fig. 57.—Buceros rhinoceros
(AFTER GARROD).
which supplies digit II. ; there may be in addition a strong
vinculum, uniting tendons before their splitting (fig. 56).
; (4) In Rhea, Phænicopterus, &c., where hallux is small
or absent, the two tendons are present, but fuse together,
branching later to supply the digits present.
; (5) In Buceros, Podargus, Sarcorhamphus, &c., the two
tendons fuse completely before supplying the digits (fig. 57).
i (6) In Megalæma, Rhamphastidæ, &c., the vinculum
is present, but flexor digitorum supplies only digit . III.,
102
STRUCTURE AND CLASSIFICATION OF BIRDS
the others being supplied by trifurcate flexor hallucis
(fig. 58).
(7) Both tendons present, but no vinculum at all in
Passeres (fig. 59).
Of these seven types there are naturally modifications
and intermediate conditions, which will be described in the
systematic part below.
Short Flexors.—Of these there are two series ; one set
L

W

DHSE
NA
KIT
222
Pro
A
M
RETURUNLESTRE
ae
PECSAVARUREZ
NWU
XSMN
**
ESS
هتد
ula
III
Fig. 58.- Megalæma (AFTER
GARROD).
FIG. 59.—A PASSERINE FOOT
(AFTER GARR01)).
arises from the bones of the metatarsus, the others from the
long tendons. We shall commence with the first set.
The flexor hallucis brevis is often (Palamedea, Aceros)
composed of two distinct muscles with separate tendons
and insertions on to the first digit.
Flexor (adductor) digiti II. is inserted on to the median
side of the base of first phalanx of digit II.
Flexor (adductor) digiti IV. arises near to the last, and
has a similar relation to the basal phalanx of digit IV.
MUSCLES OF THE HIND LIMB
103
ni
Flexor secundus (adductor) digiti IV. is a muscle which
appears to be generally absent (e.g. Ciconia), and is not,
according to GADOW, mentioned by authors. It is present
in Rhea and Bucorvus.
The last-named muscle may be the equivalent of the
first of the two short flexors which arise from the deep long
flexor tendons. Of these there are two.
(1) MITCHELL has described in Opisthocomus a muscular
slip which leaves the longus hallucis tendon and runs to the
fourth digit. A similar muscle is present in Ardea cinerea ; 1
I have found it in the hornbill, Ceratogymna elata (not in
Aceros nipalensis).
(2) Another muscle (flexor brevis digiti III. of GADOW)
arises from tendon of flexor profundus in Opisthocomus, Rhea,
&c., and passes to third digit.
Of short extensor muscles there are at most six.
The extensor hallucis, generally single, is two-headed
in Pandion, and formed of two distinct muscles in Pala-
medea.
The extensor proprius and extensor brevis digiti III. both
supply the third digit. In Aceros and Bucorvus a single but
two-headed muscle appears to represent both.
The extensor (adductor) digiti II. is not always present.
The same may be said of the extensor digiti IV.
Muscles of the Neck and Trunk
These muscles are, many of them, not easy to isolate and
describe. There is, in consequence of this, some divergence
in the published accounts. Furthermore, insufficient data
have been collected for the estimation of the use of these
muscles in classification. The account which follows is an
almost verbatim transcript from a paper upon Palamedea 3
by Mr. MITCHELL and myself.
.
. It is suggested by MITCHELL that these muscles (which require further
study) may throw light upon the origin of the very peculiar modes of distribu-
tion of the hallucis tendon in some groups of birds, as it has been repeatedly
shown that a tendon may be the homologue of a muscle.'
? GARROD MS. 3 Quoted on p. 108.
104
STRUCTURE AND CLASSIFICATION OF BIRDS
Biventer Cervicis.—The two muscles are perfectly separate
from each other. They arise tendinous from the spinous
process of the first dorsal vertebra. Then follow a tendon
of an inch long, a belly of two inches, again a tendon of four
which is inserted fleshy on to the occipital below the com-
plexus. In some kingfishers (q.v.) the two muscles are
joined by a tendinous limb.
Complexus.—This muscle arises from the transverse pro-
cesses of the third and fourth cervical vertebræ, and from
the fibres covering the intertransversarii of the same. It
is inserted, separated from its fellow by a septum, on to the
transverse ridge of the occipital. The muscle is entirely
fleshy.
Liongissimus Dorsi.—It arises by a series of fleshy fibres
from the front edge of the ilium, becomes tendinous in the
middle, and then is inserted by fleshy fibres on to the lateral
surface of the vertebral spine next in front; the next anterior
part arises tendinously from the spinous process of the most
posterior uncovered dorsal vertebra, and is inserted on to
the vertebra next in front: then follow two of precisely
similar relations; the next is carried on to the dorsal surface
of the longissimus dorsi, as also is the last or most anterior
portion.
Ilio-costalis.—This complex muscle' lies laterally to the
foregoing muscle ; it is fused at the edge with its fibres. It
arises from the ilium and from the transverse process beside
the attachment of the rib; two similar slips in front of this
arise from the transverse process and from the adjacent
surface of the rib. The ends of the slips are inserted partly
on to the surface of the ribs and partly pass on to the lateral
musculature of the neck.
Cervicalis Ascendens. This is the lateral muscle anterior
to the ilio-costalis. It consists of five distinct slips arising
from the transverse processes of vertebræ XVI.-XI., with the
exception of XII. The two posterior are inserted on to
the vertebræ next in front; the next two are inserted on to
the surface of the oblique muscles next in front; the last
MUSCLES OF THE NECK AND TRUNK
105
-
one on to the oblique muscle next but one in front. Behind
these slips, which were obvious, there were indications of
additional slips both in front and behind, but these were
not sufficiently differentiated from the adjacent muscles for
separate description.
Longus Cervicis.—This median muscle arises from the
forward continuation of the longissimus dorsi and from the
median underlying part of the spinalis complex.
Spinalis Complex.—This system of muscles lies deeper
than the foregoing. It is divisible into three parts. Part I.
(sometimes called the spinalis dorsi) arises apparently only
from the longissimus dorsi ; it gives off six fleshy bellies
which increase in length from the posterior to the anterior;
they are inserted on to the upper posterior surface of the
oblique processes of cervicals X.-XVI. In addition the
superior fibres from these heads form a well-marked rounded
muscular cord, which runs forward to form the longus colli
posticus. Part II. consists of only four well-differentiated
slender bellies; these arise from the spinous processes of
cervicals XIII.-XV., and they are inserted on to a continuous
longitudinal band, the posterior part of which sends slips
to the three posterior branches of the spinalis dorsi, while
the anterior end is inserted on to the oblique processes of
cervicals x., XI., at the roots of the anterior two spinalis
dorsi bellies. Part III. (longus colli posticus) arises from the
sides of the spinous processes of cervicals II.-XI., and from
part I. of the spinalis complex; it is inserted by digitations
which merge with the intervertebral muscles in front of its
origins. It has been specially described and figured by
GARROD for Plotus.
Rectus Capitis Posticus.-It arises from the spinous
process of atlas and axis ; its fibres spread out over the
occipital under the complexus.
Intertransversales.- These muscles are obvious all the
way along from the ilium to the neck, running between the
transverse processes of the vertebræ.
Obliqui (Transverso-spinales).--They are clearly differen-
tiated only from the last to the seventh cervical. They are
91
UU
106
STRUCTURE AND CLASSIFICATION OF BIRDS
large fleshy digitations arising from the transverse processes,
and inserted on to the lateral face of the spinous processes
next but one in front.
Rectus Capitis Anticus Major.-It arises all along the
neck from the hypapophyses and from fascia ; about the
middle of the neck it grades into the longus' colli, from a slip
of which it first arises about the level of the seventh vertebra.
Its broad fleshy insertion is tendinous on the outside, is
fused with its fellow in the middle line, and extends for
about a quarter of an inch on the anterior outer edge of the
basi-occipital.
Rectus Capitis Anticus Minor.—This is a fleshy broad
muscle underlying the preceding. Its origin is fleshy and
continuous from first four vertebræ. It has a broad fleshy
insertion to the extreme outer posterior face of the ridge
behind the meatus auditorius.
Longus Colli.-It arises from the middle of the centrum
of the second dorsal vertebra tendinously, and then by a
series of tendons from each vertebra up to the overlap of the
rectus capitis. It is inserted by a series of slips to the
vertebræ in front of its origins.
Intertuberculares.-These are a series of short muscles
forming the deepest layer of the neck musculature.
Interappendiculares Costarum.—The first arises from the
end of the last free rib, and runs backwards and downwards
to the lateral anterior process of the sternum ; the second
from the junction of the sternal and costal parts of the first
complete rib; it shortly fuses with the third, which arises
from the costal part of the next rib. These two are then
inserted together. The fourth arises from the third, fourth,
and fifth costal ribs and from the space between them, and
is inserted immediately behind the others. The posterior
ones are smaller.
Intercostales Externi.—These are confined to the whole
of the costal part; the fibres run from above in front and
downwards towards the caudal end.
Intercostales Interni.- These are confined to the lower
half of the costal ribs, and are chiefly tendinous.
MUSCLES OF THE NECK AND TRUNK
107
1
Costi-sternales.-Four slips arising tendinously from the
sternal ribs, and inserted fleshy to the sternum.
Costo-sternalis Externus.—This peculiar muscle, appa-
rently found only in Palamedeidæ, replaces physiologically
the uncinate processes, as its broad ribbon-like belly runs
diagonally across the outer surface of the ribs. It arises by
a very thin flat tendon from the third, fourth, and fifth ribs,
and from the interspaces
between them. It is inserted
to the costal edge of the
sternum half an inch from the
posterior end.

ETRANS PROC
of coca
ILIOCOCGX
FEMERO-CAUDL
Ulllllll
"LEVATOR COCG,
T
Itt
INTERN.
th
VAI11
AR
Ivices
WIIII!!!
s', so jullelloncinimui
Taoctiss..."
cfi , 2011, more!
Caudal Muscles
The caudal muscles (in DUBO.COCGX
Palamedea) are illustrated in
the accompanying figure.
Levator Coccygis.—This
arises on each side from ilium,
PUBO-COCGY EXTERI
from lateral faces of spinous
processes, and from trans-
verse processes of caudal
vertebræ. It is inserted on
to membrane covering rec-
trices.
Ilio-coccygeus.-On each
side there are two parts of
this muscle, both entirely
fleshy. They arise from the Fig. 60.-CAUDAL MUSCLES or Pala-
ilium and the ilio-sacral liga- me
i medea (AFTER BEDDARD AND MITCHELL).
ment, and are inserted on to outer rectrix. ·
Pubo-coccygeus Externuus.—This is the most posterior of
the muscles of the tail. It arises from the pubis and is
inserted on to external rectrix.
Pubo-coccygeus Internus.--Arises in front of and below
the last-mentioned. The origin extends also on to the
ischium. The muscle is inserted on to last one or two caudal
vertebræ.
Luwun
PAK
1
108
STRUCTURE AND CLASSIFICATION OF BIRDS
Depressor Coccygis.-This springs from the transverse
process of the last sacral vertebra, and from the adjacent
surface of the ilio-sacral ligament. It is inserted on to the
transverse processes of the last three or four caudal vertebræ.
Ut
Abdominal Muscles
Obliquus Abdominis Externus.—The muscle arises from
the ribs and from their uncinate processes. It ends by an
aponeurosis upon the pubis.
Obliquus Abdominis Internus.—Lies between the last
muscle and the next. It passes from the pubis, extending
on to ilium to the last true rib. A separate slip of this is
described as the quadratus lumborum, running from the last
false rib to the crest of the ilium.
Transversus Abdominis.--This is the deepest of the ab-
dominal muscles. It springs from the pubis and preace-
tabular ilium, and its aponeurosis ends in that of its fellow
in the linea alba.
Rectus Abdominis. - Springs from last sternal rib and
from sternum, and is attached to pubis.
Transverso-analis.-This passes across the abdomen in
front of the cloacal aperture, and meets its fellow. It arises
either from the pelvis or from the transverse processes of
certain caudal vertebræ.
Hyoidean Muscles
Our knowledge of the muscles of the hyoidean apparatus
and the neighbourhood is chiefly due to GIEBEL,' GADOW,?
and MITCHELL. I mainly follow the latter in his account
of these muscles in Opisthocomus and in Palamedea.
1. Die Zunge der Vögel,' &c., Zeitschr. f. d. ges. Naturwiss. xi. 1858, p. 19.
? BRONN's Thierreich, ' Aves.'
3A Contribution to the Anatomy of the Hoatzin (Opisthocomus cristatus),'
P. 2. S. 1816, p. 618; BEDDARD and MITCHELL, ' On the Anatomy of Palamedea
cornuta, P. 2. S. 1894, p. 536. See also G. L. DUVERNOY, “Mémoire sur
quelques Particularités des Organes de la Déglutition de la Classe des Oiseaux,'
&c., Mém. Soc. Hist. Nat. Strasbourg, ii. 1835; J. KACZANDER, ' Beiträge zur
Entwicklungsgeschichte der Kaumuskulatur,' Mth. Embr. Inst. Wien, 1883.
HYOILEAN MUSCLES
109
The mylohyoid anterior is a sheet of muscles passing
across between the rami of the mandible anteriorly.
The mylohyoid posterior is composed of two layers, a
deeper and a more superficial; the latter is a broad sheet of
muscle nearly reaching the mylohyoid anterior in front and

FIT FTTTTTTTT777
MTOTO
SSIOITALqartists
.
tu
uLIITIT
..
ASIL
W
Fig. 61.-HYOIDEAN MUSCLES or Opisthocomus (AFTER MITCHELL).
1, 2, geniohyoidh ; 3, 4, 5, mylohyoid ; 6, ceratoglossus ; 7, ceratohyoid ; 8, depressor
mandibulæ ; Gl, mandibular gland.
covering the space between the rami of the mandible in the
region where it is developed; the deeper layer arises in
common with the superficial layer from the rami; it is a
narrower muscle and runs forward.
110
AND CLASSIFICATION OF BIRDS
n
STRUCTURE SA
The geniohyoid is in two distinct portions; the posterior
division arises on each side from a ramus of the mandible ;
it passes backwards and is wrapped round the ceratohyoid
to its tip. The anterior portion also arises from the rami of
the jaw; it is inserted upon the ceratohyal partly under and
partly distally to the insertion of the posterior division.
This muscle is sometimes a single muscle, as, for example,
in Palamedea.
The genioglossus (entirely absent in Palamedea, &c.) is a
slight muscle, springs from the middle line near the chin,
and passes to the os entoglossum.
The ceratoglossus is a strong muscle, arises from the outer
side of the ceratohyal; it ends in a tendon which is inserted
along the side of the tongue almost to the tip. The muscle
in Palamedea, &c., is divided into two parts. ·
The ceratohyoid arises from the inner side of the cerato-
hyal and is inserted on to the urohyal.
The sternohyoid (in Palamedea) is a band of muscle which
arises from the basihyal and entoglossus; it spreads out
over the thyroid cartilage and trachea.
The hypoglossals are in Palamedea indistinguishable from
the ceratoglossus.
ULO
CD
Muscles of the Head
The temporalis (in Palamedea) is divided into two
portions; the superficial part arises from the whole temporal
fossa and from the external and internal surfaces of the
midtemporal process ; it runs to the outer upper surface of
the lower jaw; the deeper part is a pyramidal muscle ending
in a stout tendon attached to the lower jaw; in addition to
this another portion, deeper still, runs across from the forward
process of the quadrate to the inner side of the ramus, and
a wide band of muscle bridges the interval between the inner
edges of the forward process of the quadrate and the wall of
the orbit behind the optic foramen.
The pterygoid is divided into several layers which con-
nect the lower jaw with the palatines and pterygoids.
MUSCLES OF THE HEAD
111
The depressor mandibula consists of two parts which
have been termed digastric and biventer. It connects the
under surface of the occiput with the lower jaw.
Osteology
Vertebral Column.-Highly characteristic of birds is the
saddle-shaped (heterocoelous ’) form of the vertebral centra.
The existence of this mode of articulation, though confined
to birds, is not found everywhere and in all of the existing
members of the order, and is not found at all in some of the
extinct forms, Archeopteryx and Ichthyornis. As to exist-
ing birds, the opisthocoelous form is frequently met with, but
so irregularly as not to be of much use from a classificatory
point of view. The existence of such vertebræ, pointing
towards reptiles, may, however, be accepted as some indica-
tion of an archaic position in the order. The matter has
been lately summed up by the late Professor PARKER,2 from
his own investigations, and from those of others.
The dorsal vertebræ have been found to be opisthocoelous
in penguins and auks, in Limicolæ (including Laridæ), but
not in petrels; among the parrots PARKER met with this
condition in several forms, where it was found to be com-
bined with terminal epiphyses, a character which is just
commencing in the lowest mammalia (Ornithorhynchus) and
The following are a few works which deal with the general osteology of a
number of forms. More special treatises will be referred to in their proper place:-
E. BLANCHARD, 'Recherches sur les Caractères Ostéologiques des Oiseaux,'
&c., Arn. Sci. Nat. xi. 1860, p. 11; J. F. BRANDT, 'Beiträge zur Kenntniss der
Naturgeschichte d. Vögel,' &c., Mem. Acad. Sci. St. Petersb. (6), iii. 1840;
EYTON, Osteologia Aviuin, London, 1858-81 ; A. B. MEYER, Abbildungci
von Vogelskeleten, Dresden, 1879-96 ; MILNE EDWARDS and GRANDIDIER, Hist.
Nat., c., de Madagascar, 'Oiseaux,' Paris, 1879–85; C. L. NITZSCH, Osteograt-
phische Beiträge, &c., Leipsic, 1811; P. GERVAIS, 'Description Ostéologique de
l'Hoazin, du Kamichi,' &c., Zool. ini Voy. de Castelnau, Paris, 1855. Besides
FÜRBRINGER, Untersuchungen zur Morphologie v. Syst. d. Vögel, and GADOW,
· Aves,' in Bronn's Klassen v. Ordnungen des Thierreichs, for brief and largely
osteological definitions of birds see SEEBOHM, Classification of Birds, London,
1889, and SHARPE, Osteological Catalogue of College of Surgeons Museum,
London, 1891.
? « On the Vertebral Chain of Birds, Proc. Roj. Soc: xliii. 1888, p. 465.
112
STRUCTURE AND CLASSIFICATION OF BIRDS
entirely exceptional among birds. Steatornis is another bird
with opisthoceelous vertebræ. So too are the cormorants and
darters. Another form of vertebral articulation met with
in reptiles-namely, the procoelous articulation-also exists
in birds. In all birds, of course, the atlas is procoelous,
articulating with the convex occipital condyle. In many
birds “the last two movable joints in the caudal series
become proccelous.'
The biconcave form of vertebræ characterises the extinct
Archeopterys, and the gull-like Ichthyornis, called by its
name on this very account. The concavities, however,
according to FÜRBRINGER, seem rather to have been produced
by the maceration out of a plug of cartilage than to have
characterised the unaltered vertebra. It is doubtful, in fact,
whether the spaces left in the fossil vertebræ were filled
during life with copious remains of the notochord, as in
fishes.
The vertebral column of birds can be distinguished into
four series, as in the higher vertebrates generally. It is
customary to regard as cervical those vertebræ which either
have no movable ribs or, if they have, do not become con-
nected through their intermediary with the sternum. The
rib-bearing vertebræ are the dorsal series, while those which
articulate with the pelvis are usually termed sacral. But
it seems better to reserve the term 'sacral' for the two
vertebræ which, in the chick, bear the ilium.
The number of true sacrals is not, however, always two.
J.J. PARKER ? describes in the young Apteryx three vertebræ,
which abut upon the ilium, and are the only ones in which
there are separate rib-like ossifications at the ends of the
transverse processes. These vertebrae, which are quite con-
spicuous in the adult (fig. 62), are regarded as the true
sacrals. There are also three in the ostrich (fig. 63). In
other birds (e.g. Larus, Chionis) there is apparently only
one sacral vertebra.
Behind the sacrum are the caudal vertebræ. Archæo-
pteryx is unique among birds for its long tail, composed of
1 Not certainly. ? • Development of Apteryx,' Phil. Trans. 1891.
CU
OSTEOLOGY
113
separate vertebræ. In all other birds the tail is short and does
not extend far beyond the sacrum. In the majority of carinate
birds the terminal vertebræ are fused together into the highly
characteristic ploughshare bone (urostyle or pygostyle).'
at
e

lp
ww.
AS
C
SI
ED
w
4
.
1
.
ET
LL
.
- A
.
.
-
-
-
VYAX
mom
S
OS
S
AVIZE
DU
2
2.
2
ASS
.
24
2
O
SAMER
: :
Denne
-
RSS
.
CAN VINUA
11
.
LIS
RASESE
SI
Oli
ZEZE
WWW
VINILI
. .
.
1
PIA
2
.
S
.
.
ERRE
VITA
Hea
W
*
-
.
_
PI
NA
UA
A
Ip
at
á i
FIG. 62.-PELVIS or APTERYX. FROM BENEATH. (AFTER MIVART.)
il, ilium ; », pubis ; i, ischium; lp, prepubic process.
There is, however, a closer correspondence between
the tail of Archaeopteryx and that of the carinate bird
M

,
?
V
TIVO
CY
SH
SA
Mine
X
16"
.
C
S2
VN
SN
-
-
.
1
.
SUT
.
BS SEASES
SE
3 .
BE
lis
-
SA
-
TA
Blon
VR
.
SON
in
Spremni
WAT VAN
EE
S14
me
111
14.
3
dg
SAMA
ZO
W1967
LIS
e
dp. 11
28.9.10
Fig. 63.—LUMBAR AND SACRAL VERTEBRA OF AN IMMATURE OSTRICH
(AFTER MIVART).
8, 9, 10, sacral vertebræ ; P, parapophyses ; a, diapophyses.
than might be assumed from the last-mentioned differ-
ences. The first four caudal vertebræ of Archæopteryx have
strong transverse processes, which are weaker, but present,
on the fifth, which thus affords a transition to the remaining
sixteen, upon which there are no such processes. In the
W. MARSHALL, Untersuchungen über den Vogelschwanz,' Ned. Arch. f.
Zool. i. 1873, p. 191.
114
STRUCTURE AND CLASSIFICATION OF BIRDS
same way the free caudals of carinate birds have transverse
processes, which are at most faintly represented upon the

Se
1
.
SPOTI
.
.
*
CI
H 3.2
WHAT?
.
H
ti
.
.
.
.
.
.
..
I
.
.
. .. ..
'I.....
.
.
NRV
....
www
C
....
.
--
.
G
:.
STA
HUA2
AVTO
S
NAL
AT
-
MIN
1
.
1
NDIY
juin
sowW
$
19
..
.
."
111
TV
171
A
.
..
.
.
.
.
IZUIA
.
Fig. 64.-RIBS, STERNUM, AND PELVIS OF Chunga Burmeisteri (AFTER BEDDARD). THE UPTURNED PYGOSTYLE
IN ITS NATURAL RELATIONS IS SHOWN.
112
.
)
IRUDIN
1
Un
TA
21
INCHES
INCHES
kwmood.co.
Million,
in
3:
::
wurm mittimet Muhimu
...
:
th
WW
P
SCALE OF
fused posterior set of caudals which form the pygostyle.
Four of the posterior caudals of Archæopteryx have fine
OSTEOLOGY
115
lu
splints of bone lying on one side, which have been compared
to the ossifications in tendons found among the ptero-
dactyles. They may conceivably be misplaced chevron
bones.
The pygostyle varies much in the degree of its develop-
ment. It is weakest in various aquatic birds, such as the
auks and grebes, where it is thin and narrow; in more
purely flying birds it is very thick at the base, and is turned
upwards instead of, as in the auks, carrying on the line of
the tail. In the grebe there is really no more definite a
ploughshare bone than in the ostrich. The number of
vertebræ which are fused together to form the urostyle
varies. In the ostrich MARSHALL finds four, five in the
grebe and hornbill, six in the duck and in Eurylamus.
The total number of vertebræl in the column varies
greatly; the extremes are something like thirty-nine and sixty-
four (reckoning the urostyle as one). The greatest number
characterises the ratites, and the smallest some of the higher
arboreal birds. Archeopteryx had only about fifty vertebræ.
While, therefore, it may be generally true to put down as
older types those with the largest number of vertebræ, it is
evident that on this view Archæopteryx must be regarded as
a parallel branch to the existing birds, and not as their
ancestor. The number of vertebræ, though it may perhaps
be considered from this general point of view, is not of the
fainlest use for the systematic arrangement of existing forms.
The number varies so extremely that among the . Gruidæ
Professor PARKER found no two alike. Rather more fixed,
but still subject to variation among the species of a genus,
are the cervical vertebræ; .and some account will be taken
in the pages which follow of this fixedness. The results
must, however, be tempered by the reflection that while the
common swan has twenty-five the black-necked swan has
twenty-four.
Between the successive centra are the intervertebral
1
I GIEBEL ("Die Wirbelzahlen am Vogelskelet,' Z citschu. f. d. ges. Nat. xviii.
1866, p. 20) gives a long list; see also "Der letzte Schwanzwirbel des
Vogelskeletes,' ibid. vi., 1855.
I 2
116
STRUCTURE AND CLASSIFICATION OF BIRDS
11.84
ns
-
-
is
.
alin "
t
10
KAI
W
ES
discs,' the 'intercentra' or 'basiventral' elements. These
are, as has been shown, originally the portions of each
vertebra with which the ribs articulate, from which they
are outgrowths. But as the ribs come to articulate with the
centra these structures degenerate. In the development of
Apteryx T. J. PARKER found a postoccipital and a post-
atlantal intercentrum, and two in the caudal region, which
ossify so as to retain their independence in the adult
skeleton.
Intercentra in the caudal region of the bird's vertebral
column are by no means so rare as might be inferred from
some published statements upon
the matter. They are especially
conspicuous among the Limi-
colæ and the nearly allied auks,
and in most water birds. In
Numenius femoralis, for exam-
ple, there are three smallosseous
nodules lying between caudal
vertebræ 1-5. Behind these
FIG. 65.- LAST TWO VERTEBRÆ Or are a series of hypapophyses,
STRUTHIO (AFTER MIVART).
which are a continuation of
us, neural spines : (), osseous bridge.
the same series, but much more
pronounced and ankylosed to the vertebræ.
They exist also in the duck tribe. In Biziura lobata
there are three distinct intercentra in the form of largish
nodules. I have found intercentra also in Palamedeæ, Tubi-
nares, Steganopodes, Colymbi, Herodiones, Opisthocomus.
These free intercentra are rare among the Pico-passeres,
but in a few of them are present. Thus in Toccus there is
a distinct intercentrum lying between the last free caudal
vertebræ.
The hawk tribe have not these bonelets as distinct struc-
iures.
In the cuckoos, parrots, Ralli, Otides, Columbæ, and the

SL.
| This matter of the composition of the vertebra has been recently gone into
by GADOW (on the 'Evolution of the Vertebral Column of Amphibia and Amniota,'
Phil. Trans. 1896, p. 1), who quotes previous literature.
OSTEOLOGY
117
tinamous I have not seen in the adult skeleton any free
intercentra; nor in the Grues, excepting Chunga.
Further details on this matter will be found in the paper
cited below.'
Though free intercentra are by no means universal
among recent birds, hypophyses of the last caudals are
almost so. That these latter are derived from intercentra,
and are, therefore, not comparable to the hypapophyses of the
cervicals and dorsals, is clear from such cases where the gra-
dual transition between free intercentra and fixed hypapophy-
ses is shown. In reptiles the intercentra are in the tail region
constantly in the form of chevron bones, which are V-shaped,
articulating with the vertebral column by the free ends of
the V. This form of the hypophyses of the caudal region is
not so common as a simply bifid condition, but does OC-
casionally occur. I have seen it, for example, in Tubinares,
Accipitres, and Cuculi.
The first vertebra of the cervical series is called the
Luult.
part of the centrum’ is formed by the projecting odontoid
process (see fig. 67), the rest being formed by a pair of
intercentra. In the hornbills the atlas is fused with the
following axis vertebra.? Generally the atlas has not what
the succeeding vertebræ have, a vertebrarterial canal, but
this is sometimes present (see under "Ribs,' p. 119). The
odontoid process sometimes notches the lower part of the
atlas, and sometimes perforates it. These two conditions
are illustrated by figs. 66 and 68. It sometimes happens that
the neural arch of the atlas is incomplete, e.g. Chunga,
Colius, Pandion. As a rule it is perfect.
In the cervical vertebræ the chief facts which appear to
be of systematic importance are the relations to each other
of the paired processes, to which MIVART has applied the
name of catapophyses. These are sometimes inconspicu-
ous processes of the transverse processes on the under
| BEDDARD, 'Note upon Intercentra,' &c., P. Z. S. 1897, p. 465.
? In a specimen of Chunga I have found the same fusion.
118
STRUCTURE AND CLASSIFICATION OF BIRDS
approach each other in the middle line, as in Psophia.
Sometimes a number of these processes unite to form a
canal ; this occurs in the Steganopodes, and most Herodiones
(but not in Scopus umbretta) ; but the classificatory signifi-
cance of the fact is marred by the occurrence of a similar
canal similarly formed in some Picidæ, and in the case of
one vertebra in the parrot, Eclectus polychlorus.
It is sometimes the case that the last of the catapophyses
is consolidated into a thick process, which is bifid at the
extremity; this process forms a transition to the following
hæmapophyses (or hypapophyses). These latter are un-

ns
az ha a terme
hp


ula
-
VINA
Pants
ER
2
*
A
HAVN:
.
ac
S
hý
Fig. 66.- ATLAS or
EMU (ATTER
MIVART).
ac, articular surface;
♡, vertebrarterial
canal; hy, hyper-
apoplyscs.
Fig. 67.—AXIS OF EMU (AFTER
MIVART).
0, odontoid process ; ns, neural spine ;
(la, anterior zygapophyses; pl,
pleural lamella ; pc, articular sur-
face; hu, hy papophysis ; hy, hyper-
apoplysis.
FIG. 68.--ATLAS Or
CASSOWARY (AFTER
MIVART). LETTERS
AS IN FIG. 66.
paired median processes, which commence upon the cervical
vertebræ, and extend for a variable distance back along the
dorsal vertebræ. They are very feeble, and sometimes
limited to the cervical region, in the Herodiones. They are
most highly developed in Sphenisci, Colymbi, Alcæ, and some
Anseres, being in these cases continued to the end of the
dorsal series, and even being found upon some of the lumbar
vertebræ. In many cases these processes are flattened out
at the free end like an inverted T, or are trifid at the same
place. This is seen to be due to the gradual shifting in
position of a posterior set of catapophyses, which at first are
at the sides of, and far from, the hæmapophyses, but get
OSTEOLOGY
119
nearer and nearer, until at length they mount upon the
hæmapophysis itself and pass to its very end. Details of the
formation of the vertebræ will be found in the systematic
part of this book.'
Ribs.2-The ribs of birds vary greatly in number. There
are as a rule three series of ribs to be distinguished. The
last cervical vertebræ, more or fewer of them, are furnished
with short ribs which do not reach the sternum. Behind
these are, again, a variable number of true ribs, which do
reach and articulate with the sternum. These true ribs
consist of the vertebral portion, which articulates with the
vertebra, and of a sternal portion, which is articulated with
the vertebral half of the rib above and with the sternum
below; it is bent at an angle with the vertebral portion.
Attached to, originally separate from, and sometimes per-
manently separate from, the vertebral half of the rib is the
uncinate process, of which there are a variable number.
These processes are absent 3 in Archæopteryx and in the
Palamedeæ only. Behind the true ribs, which articulate
with the sternum, are a variable number, in all degrees of
1 The relationship of the so-called catapophyses to the unpaired hæmapo-
physes varies, and suggests—what has been advanced on other grounds-an
occasional excalation of vertebræ. Without wishing to commit myself to a
belief in the actual dropping out of a vertebra from the middle of the series, I
may mention some of the facts which may be regarded as pointing in this
direction. In the grebe Æchinophorus the catapophyses form on certain
vertebræ a complete ventral canal for the carotids. The summit of the arch
thus formed gradually acquires a median dorsal process. This increases, and
the catapophyses finally end in the obliteration of the canal which they sur
round, and a solid arch is formed; the hypapophysis of the succeeding vertebra
is single and no longer retains traces of its evolution from a ring of bone sur-
mounted by a process. In other cases the catapophyses suddenly end and the
hypapophyses begin without such intermediate stages. An intermediate stage
is seen in certain types where the catapophyses end suddenly, but the first
hypapophysis is double, either formed of two ciearly fused pieces or with merely
a bifid spine. These latter cases suggest the dropping out of one or more
vertebræ, effecting the transition between the paired catapophyses and the un-
paired hypapophyses.
? In all birds except Archocopteryx the ribs are two-headed with a capitulum
and tuberculum.
3 They have been often said to be absent in Dinornis, but they are not.
W. BEHRENS, Untersuchungen iibcı den Processus uncinatus der Vögel und
Crocodile, Inaug. Diss., Göttingen, 1880.
120
AND CLASSIFICATION OF BIRDS
7
STRUCTURE degeneration, of floating lumbar ribs. Morphologically
equivalent with ribs are the processes firmly ankylosed to
the cervical vertebræ, which form a canal for the vertebral
artery; these are, as a rule, absent from the atlas, but are
present on that vertebra in the Anseres, Opisthocomus,
Triponat Feddeni, Dromcus 2 (fig. 66). Archæopteryx is
alone in possessing the abdominal ribs of the crocodiles and
other reptiles.
The Shoulder Girdle.3—The shoulder girdle of birds consists
of at any rate three separate elements—the scapula above ;
the coracoid, articulating with the sternum; and the clavicles,
generally united into a U-shaped piece. Of these the first
two are preformed in cartilage, the last in membrane.
The scapula is a thinnish sword-shaped bone which
is attached by muscles to the ribs and to the vertebræ,
and lies in a direction, as a rule, nearly parallel to the
long axis of the body. The scapula 'does not show great
variability of form among birds; the most considerable
variation is to be seen in the penguins, where the bone is,
comparatively speaking, of enormous width. ' A free supra-
scapula has been noted by PARKER in Opisthocomus. The
coracoids articulate on the one hand with the scapula, and
on the other with the sternum, where they are received into
grooves on its anterior margin. There are some variations
in the way in which these grooves are arranged : in some
birds the two coracoids at their insertion are not in contact
at all ; in others they are in contact; and finally they may
overlap, as in reptiles.
The coracoid has in many birds a procoracoid process,
which is believed to be the equivalent of the procoracoid of
reptiles. This is especially prominent in the ostrich, but is
present in a large number of other birds, though more
reduced in extent. But its large or small size is so capricious
1
Stated by PARKER to be absent.
2 MIVART figures a canal on one side of the atlas of the ostrich.
3 A. SABATIER, Comparaison des Ceintures et des Membres Antérieurs et
Postérieurs dans la série des Vertèbres, Montpellier, 1880; PARKER, quoted
below. See also LÜHDER in J. f. 0. 1871, p. 321.
OSTEOLOGY
121
22
UUU
in its relations to other structural similarities and dissimilari-
ties that the fact is not of great use in classification.
The same remark may be made about the foramen cora-
coideum perhaps, which, again, is found in many birds and
absent from others. As to the morphological significance of
this foramen, which transmits a nerve twig to the pectoralis
secundus, it may perhaps be regarded as the boundary
between the coracoid and the procoracoid.
In the course of the development of the common fowl,
according to Miss LINDSAY, whose figures are here reproduced,
there is a very considerable trace of the procoracoid. The
three elements of the shoulder girdle are perfectly distinct
from each other in the young embryo, but become fused (the
scapula and the coracoid), again to get separate in the older
chick. This temporary fusion may be significant of the
struthionic condition to be described later. The intermediate
piece is, it will be noticed, triangular in form, the elongated
aspect of the adult coracoid being acquired later. Miss
LINDSAY is of opinion that this change of form is to be cor-
related with the disappearance of the anterior section of the
bone, as indicated in the accompanying diagram, the disap-
pearing (shaded) part being the equivalent of the procora-
coid.
The interrelationship of the scapula to the coracoid offers
facts of some importance. In the ostrich tribe the two bones
are firmly ankylosed; this is not the case with the young,
but it is plainly the case with the adult. In carinate birds,
on the other hand, there is not ankylosis, but a close union
by means of fibro-cartilage. It appears, however, that in
Didus (exceptionally ?) there is an actual synostosis, which of
course bears out the suggestion that the synostosis of the
ratite birds has something to do with their loss of the power
of flight. In the ratite birds and in Hesperornis the scapula
and the coracoid are nearly in the same straight line, the
angle in Apteryx varying from 150° to 122°, whereas in the
carinates the two bones are at right angles or at an even
acute angle. That this is not a morphological distinction,
but is distinctly related to the development of the shoulder
122
STRUCTURE AND CLASSIFICATION OF BIRDS
muscles, has been clearly pointed out by T.J. PARKER." He
discovered an approximation to the struthious condition in
several of the flightless rails and other birds. But the state
of affairs which characterises the Tubinares warns us against
placing too much reliance upon this apparently sound gene-
ralisation ; for in them we are informed by FORBES that
the angle it' (the scapula) "forms with the coracoid varies
much in different genera, being most acute in Pelecanoides,
whilst in the Oceanitidæ it is hardly if at all less than a right

CA
.
.
..
SKA
..
com
SO
Co
SC+C
int
co
SC
FIG. 69.-DEVELOPMENT OF SHOULDER GIRDLE OF CHICK (AFTER LINDSAY).
cl, clavicle; pc, procoracoid ; cor, coracoid ; sc, scapula. 1-3, fifth day; 4, sixth day ;
5, late on sixth day.
angle. The widest angle in a carinate bird is 106°, so there
is a difference of only 16° between extremes of carinates and
ratites.
The two clavicles 2 sometimes spoken of collectively as
the furcula vary much in their degree of development. They
are totally absent in the Apteryx. In the emu and in certain
parrots they are distinct and smallish bones which do not
come into contact with each other ; but in the majority of
birds they form a single U- or V-shaped bone.
The furcula varies in the expansion or non-expansion of
the base to form a circular hypocleidium. In some birds the
T'On Notornis,' in Tr. N. Zealand Inst. xiv. 1882.
? A. WEITZEL, 'Die Furcula : ein Beitrag zur Osteologie der Vögel,' Zeitsclır.
f. d. ges. Naturw. xxv. 1865, p. 317.
OSTEOLOGY
123
A
furcula is connected with a ligament (e.g. Psophia) by articu-
lation (e.g. Herodiones) or by direct synostosis with the carina
sterni. In the gallinaceous birds the furcula does not come
into near relations with the carina, and in Opisthocomus--
quite exceptionally—the bone is ankylosed with the spina
sterni on the one hand, and with the coracoids, so firmly
that.' no trace of the primitive distinctness of the bones is
discernible. There are also considerable variations in the
degree of the connection between the furcula and the coracoid
and scapula.
In a few birds the ends of the clavicles where they arti-
culate, or at least are connected, with the coracoid and scapula
have a process, the acrocoracoid process of the clavicle. This
is seen, for instance, in the Anseres, and the rudiment of such
a process in the flamingo appears at first sight to be a duck-
like character in that bird. But the same process is also
developed, and to a great extent, in the Alcedinidæ, a fact
which must be borne in mind before coming to any such
conclusions.
FÜRBRINGER has devoted some space to describing and
illustrating the relations at their articulations between the
clavicle, coracoid, and acrocoracoid. The two extremes may
be seen in Phalacrocorax and Psophia; in the former the
clavicle articulates with the acrocoracoid only, and does not
reach the scapula ; in the latter, where the procoracoid is
well developed, the clavicle comes into contact with all
three. Further details will be found under the description
of the different groups.
The Fore Limb.—The fore limb is present in all birds except
most Dinornithide, where up to the present no trace of one
has been discovered. In Hesperornis only the humerus
appears to exist; in Apteryx, Dromæus, and Casuarius there
is but one finger. With these exceptions the wing of birds
consists of a humerus, radius and ulna, carpus, metacarpals,
and three fingers (with sometimes a rudiment of a fourth);
even Archæopteryx has not been definitely shown to possess
1.
LA
A. TSCHAN, Recherches sur l'Extrémité Antéricure des Oiseaux et des
Reptiles, Diss. Inaug., Geneva, 1889.
124
STRUCTURE AND CLASSIFICATION OF BIRDS
more than the typical three fingers (see, however, below).
The relative length of the arm varies much in birds; it is
longest in the flying gulls, terns, &c., whence the name
applied to the former of Longipennes. In the struthious
birds it is the shortest, and in many running birds the wing
is reduced in length. There is too variation in the relative
lengths of the humerus, fore arm, and hand. In the divers,
for instance, the upper section of the arm is the longest, in the
gulls the fore arm, and in the penguins the hand. The
length of the hand in the Macrochires is so great that it
equals that of the humerus and fore arm together. The
exact reverse is seen in the ratites, where the length of the
humerus is greater than that of the rest of the wing. PYE-
CRAFT has brought out the interesting fact that during the
growth of Opisthocomus the proportions of the different sec-
tions of the wing alter.
A study of the relative lengths of the different parts of
the arm shows that a reduction of the wing, and a consequent
3
follow the same path. In the ostrich the middle segment is
the shortest, in the cassowary the hand.
The length of the humerus, the exact form and degree of
development of the deltoid ridge, and of the tubercles for
the insertion of muscles, furnish systematists with reliable
points for the identification of genera and species. So much
of our knowledge of extinct birds depends upon fragments of
characters of this description has been thoroughly appraised.
A glance, for instance, at LYDEKKER'S recently published
Catalogue of the Fossil Birds in the British Museum' will
reveal the importance of the power of discriminating species
by such slight indications, which furnish the student of
affinities between families or genera with nothing tangible.
The radius and the ulna are always separate bones, of
which the ulna is the longer; it is frequently marked on its
outer surface with tubercles, to which the quill feathers
are attached. The most striking modification of the radius
is seen in the Parridæ (fig. 70, p. 125), where it is prolonged
OSTEOLOGY
125
If
on the outer side into a strong flat process, the upper surface
of which is slightly grooved for the reception of the tendon
of the extensor metacarpi radialis muscle.
The carpus of recent birds consists only of two separate
bones. But in the embryo there are six separate cartilages.
The two bones which persist are looked upon by ZEHNTNER
as ulnare + intermedium and radiale + centrale. The three
distal carpals, according to PARKER, fuse with their three
metacarpals. In the emu, according to PARKER, there are
no carpal elements either in the young or adult, in Casuarius
galeatus there is a small ulnare.
Though no bird has more than three more or less com-

*
FIG. 70.-RADIUS AND ULNA or Metopidius (AFTER FORBES).
plete digits, there is commonly a trace of a fourth meta-
carpal, found by ZEHNTNER in the development of the swift,
and by STUDER in the development of the penguin. PARKER
was convinced of the existence of a prepollex and of inter-
calary digits, but WIEDERSHEIM looks with no favour upon
this broadening of the hand.
The metacarpals are free only in Archæopteryx and
Gastornis ; in all other birds they are partially fused. The
formula for the phalanges in Archaeopteryx is I. 2, II. 3,
III. 4. In some other birds it is I. 1, II. 2, III. 1, with the
exception of the ostrich, Numenius, and the embryo duck,2
where digit III. has a small additional phalanx. In other
birds the formula is I. 2, II. 3, III. 1, and in the apteryx
digit II. shows three phalanges in the course of its develop-
LI
I PARKER, 'On the Structure and Development of the Wing in the Common:
Fowl,' Phil. Trans. 1888, p. 385, where previous literature is quoted.
? BAUR, Science, vol. v. p. 355.
126
STRUCTURE AND CLASSIFICATION OF BIRDS
ment, of which one (apparently the middle one) is not
recognisable in the adult.
LEIGHTON has contributed to this question with a study
of the development of the wing of Sterna.! He finds here
too a rudimentary fourth digit, which in the first stage,
which he figures, is as long or nearly as long as the first
digit. A rudimentary metacarpal even persists attached to
the side of the last metacarpal in birds just before hatching.
In the carpus there are never more than four distinct
cartilages; there are in the first place a radiale and ulnare,
3

1
LAYI
WS
Inilah
'.
6
.
INSTALLA
KW.
TA
–Phi
-Phl=
|
SW
Ph2-47
. cute
-
-P72-
-Ph2t
US
-Ph3&4 che
Ph34-
Sieci
TI
Fig. 71. -DIGITS OF OSTRICH (AFTER WRAY).
1, phalanx 1 (Phl) and rudimentary phalanx 2 (Ph2) of digit III.; c, connective tissue.
2, another specimen with phalanges ankylosed. 3, distal part of digit IJI. of
embryonic manus (4).
and distally two cartilages, of which one appears to represent
the combined distalia of the two first digits, and the second
that of the third digit. In birds, just before hatching, all
the distalia have fused into one mass. The cartilages
lettered respectively radiale and ulnare in the figures are
thought, however, by the author to be really radiale +
intermedium and ulnare + centrale ; and in support of this
view is the partial separation between the two supposed
elements of each, which is, however, never carried very
far.
As to the homologies of the digits in the adult with those
1The Development of the Wing of Sterna Wilsonii,' Tufts Coll. Studies,
1894. Previous literature is here quoted.
OSTEOLOGY
127
of the reptilian hand, LEIGHTON leans to the view that
the supposed pollex is really the index. In putting forward
this opinion he rests first of all upon the fact that the radial
artery is absent, thus indicating a reduction of the radial
side of the hand; the second argument is derived from the
fact that in animals with a reduced manus the first digit
is the first to go, and then is followed by the last ; thus in
Orohippus there are four digits, the first having disappeared,
while in Protohippus the fifth has vanished. In addition
this view is moreover strengthened by a consideration of the
most reduced manus that occurs in birds ; in Apteryx and
Casuarius the reduction has similarly occurred on both sides
of the large persisting digit, which is thus to be regarded as
No. III.
Sternum.—The sternum in its most complicated condition
consists of the following regions (see fig. 72): Anteriorly
it ends in a moderately narrow extremity which is known
as the manubrium sterni or rostrum. On either side of this
is a forwardly directed process, the costal processes or
anterior lateral processes. In the middle of the sternum,
and forming the great projecting keel, is the lophosteon or
carina sterni, or keel. The sternum ends in a median
process behind (sometimes, but wrongly, called the xiphoid
process), to which are appended two processes on each side,
which may be termed middle and external xiphoid processes,
or these may be termed, for reasons which will appear later,
the posterior lateral process and the accessory process. The
nomenclature first used in the preceding brief descriptions
is that of HUXLEY; the second set of terms which will be
used throughout in the descriptions which follow are those
used by Miss LINDSAY in her paper upon the development
of the avian sternum.
• The sternum is subject to much modification among
birds, of which the principal varieties will be now described.
The birds which show perhaps the greatest difference from
the gallinaceous type, selected for the above description, are
the ratite birds. In them there is no keel developed, hence
1. On the Avian Sternum,' P.Z. S. 1885, p. 684.
lll."
128
STRUCTURE AND CLASSIFICATION OF BIRDS
the name ratite (raft-like), or at most, as in Rhea, a slight
protuberance, which, however, as will be pointed out imme-
diately, is not really comparable to the keel of the carinate
birds. There are, however, other birds, such as the extinct
Cnemiornis and the living
Stringops, in which the
keel is absent, its ab-
sence being associated
with the loss of the

ir
***
.
www.

***
.
п, ср
www
.
IS:
NE?
SINTA
.
....
.
.
.
THE
WIS
N11
.
er
1
.
.
.
1
.
.
M
.
.
.
Wint:
.
.
.
.
.
.
.
.
NA
.
TE
RA
COV
SEE
p
W
M ER :
VIH
T
+
is. QC
A4
., 11.viere :
ilti ükselenco
:..::?..
.
blizini
17
.
A
A
M
.cx
Full
TA
Fig. 72.-STERNUM OF Lopho-
phorus impeyanus (AFTER HUXLEY).
X, rostrum ; (P, anterior lateral process;
p.1.0, posterior lateral process ; C.x, 1.2,
its inner and outer divisious ; 7.0. carina.
Fig. 73.-STERNUM OF Podica
senegalensis (AFTER BEDDARD).
Cl, clavicle ; co, coracoid; cl, x, articula-
tion of clavicle.
power of flight. In the singular Opisthocomus the anterior
part of the keel is, as it were, cut away (the enormous crop
resting here), the posterior region being retained. The four
posterior lateral processes of the sternum figured above are
not always present in birds. The extremest modification
is as seen in the goose and the crane, where the posterior
OSTEOLOGY
129
margin of the bone is entire, without any processes at all.
In passerine birds generally, and in some others also, there
is but a single pair of these processes; while, finally, by
excessive growth of the parts concerned the processes have
joined and converted the notches into foramina. "The con-
verse course of events has been suggested i.e. that deficient
ossification leads to the fenestrated condition, whence to
the posterior notches is an easy step. Development, how-
ever, shows that the former view is the more correct. The
diversities in the form of the sternum undoubtedly must

(
са
ca
STA
230
MY
• nekim
*
.
.
t.
MMM

.
.
.
/71
1
.di.
1
.
..
Wir
.
SA
n
8
.
..
7
.
.
E34A2EE
.
.
.
.
.
.
.
.
.
.
Fig. 74.-STERNUM OF EMU (AFTER MIVART). NATURAL SIZE.
ca, anterior lateral process; C, grooves for coracoids; f, elevation in centre; mx, posterior
end ; is, lateral view showing articulation of ribs.
have some relation to the muscles which are inserted on to
and take their rise from the margins of the bone. Thus, as
already mentioned, the flat sternum of the Ratitæ is associated
with the slight development of the pectorales muscles and
the consequent loss of capacity for flight. It has been
ingeniously suggested that the relative development of the
posterior lateral processes of the sternum has possibly an
analogous explanation. The muscles that are attached
thereto are mainly the pectorals and the abdominals. Now
the pull of these two is in an opposite direction. The
tendency of the action of the pectorals would be to
130
STRUCTURE AND CLASSIFICATION OF BIRDS
straighten the posterior margin of the sternum, while
that of the abdominals would be to pull it out, perhaps
irregularly. Hopping and walking birds might therefore
be expected to have a more notched sternum than purely
flying birds; that there is some relation of this kind seems
possible when we contrast the sternum of the running
gallinaceous bird with that of the essentially aerial eagle.
Moreover, since the pull of the abdominal muscles is in two
directions, one antero-posterior (recti), the other oblique (the
obliqui), we might expect to find what we actually do find, a
direction of the xiphoid processes which corresponds with
the resultant of these two forces, as is indicated in the
annexed diagram. There are a few other modifications in
the shape of the sternum which have been made use of for
systematic purposes, besides the keel and the notches, or
excavations of the posterior border. The rostrum of the
bone is sometimes very pronounced, and sometimes practi-
cally absent altogether. According to its position, more
dorsally or more ventrally, the process has been called by
FÜRBRINGER spina externa, or spina interna sterni. In
the gallinaceous birds the two are combined in a vertically
compressed plate of bone which arises both from the lower
and from the upper side of the sternum. In the passerines
and in the todies, and a few of the allies of these groups of
birds, the anterior process of the sternum is more or less
The sternum of birds arises, as does that of other verte-
brates, in the first place between the ends of the ribs which
fuse together. Birds invariably have a few 'floating 'ribs
at both ends of the sternum which are no longer connected
with it, this connection being often lost ontogenetically.
There is, in fact, usually a shortening of the sternum during
development. The keel arises from the conjoined edges of
the two sets of fused ribs; it is not preformed separately as
a median piece. This seems to settle in the negative an
earlier view that the carina sterni was the surviving repre-
sentative of the interclavicle of the reptiles, a view which
commended itself to more than one anatomist of distinction,
OSTEOLOGY
131
and appeared to be strengthened by the occasional connec-
tion by ligament and bone with the hypocleidium.
The most recent modification of this view is put forward
by PARKER, who has shown in Opisthocomus a needle-shaped
splint of bone lying upon the keel, and therefore independent
of it.
The development of the sternum throws a light upon the
homologies of its different parts in different birds, and in
other vertebrates.
It is plain in the first place that the spina externa and
the spina interna have nothing whatever to do with the
manubriuin sterni of the mammal; for they are in the bird)
secondary outgrowths, and not, as in the mammal, part of the
primitive sternum formed by concrescence of the ribs. The
same holds good of the posterior median region of the bone,
which is a secondary outgrowth, and can therefore have no
relations with the xiphoid process of the mammalian ster-
num ; what does correspond to the latter are the posterior
lateral processes of the avian sternum.?
Pelvis.2—The pelvis consists of three pairs of bones, the
ilium, ischium, and pubis. In the young embryo these
bones form a continuous sheet of cartilage, but are all
separate distally; the ilium is directed in an antero-posterior
The literature of the sternum is large, and is to a considerable extent to be
found under the several groups. Memoirs of a wider scope are W. K. PARKER,
"A Monograph on the Structure and Development of the Shoulder Girdle and
Sternum in the Vertebrata,' Ray Soc. Publications, 1868; L'HERMINIER,
Recherches sur la Marche d'Ossifications,' &c., Méin. Ac. Sci. 1830. The
history of the development of knowledge concerning the ossification of the
sternum and the classificatory results therefrom is treated by NEWTON in Dict.
Birds, 'Introduction.' Miss LINDSAY's paper, already quoted, contains references.
to the chief memoirs upon the subject. See also R. DIECK, De Sterno Aviuin,
Diss. Inaug., Halæ, 1867.
?C. GEGENBAUR, “Beiträge z. Kenntniss des Beckens der Vögel,' Jeri.
Zeitschr. vi. p. 157; MEHNERT, · Untersuchungen über die Entwicklung des
Os pelvis d. Vögel,' Morph. J.B. xiii. 1888, p. 259; A. JOHNSON, “On the
Development of the Pelvis Girdle, &c., in the Chick,' Quart. J. Micr. Sci. 1883,
p. 399 ; B. HAIJ, Jemförande Studier öfver Foglarnes Bäcken, Lund, 1887, and
'Morphologisk Byggnoden af Ilium,' &c., Act. Lund. Univ. xxii. 1887, p. 1;
G. BAUR, ‘ Bemerkungen über das Becken d. Vögel v. Dinosaurier,' Morph. J.B.
x. 1885, p. 613; A. BUNGE, Untersuchungen zur Entwicklungsgeschichte des
Beckergiirtels, &c., Diss. Inaug., Dorpat, 1880.
K
2
132
STRUCTURE AND CLASSIFICATION OF BIRDS
direction; the ischium and the pubis look downwards and
slightly backwards ; at the end of the pubis, near to where
it comes into contact with the iliac portion of the cartilage,
is a forwardly directed process, the prepubic process. This
primitive state of affairs has been most nearly preserved in
Apteryx and Dinornis; in these birds the pubis and ischium
are free from each other distally and from the ilium; their
direction is, however, more backwards than in the embryo,
and the prepubic process is relatively smaller. In all other
birds the pubis and the ischium lie in a line more parallel

i?
VESSA
.
R
JU
Whilmilir:
UUTA 0717
Wh
EO
.
25
62.
.
Abilim
S
MIS
-
YTI
R
'.
Si
*
*
.
E-
N
NO!
I LANIMISM
.
:.
...
2
..
.
.
1
17
.
-
-
-
11
.
1
-_
SEN.
-
C
.
ES
NN
NI
N
HA
TONNI
U 1 .2012
orld
H
VITU
-
VROWW'zMUWA
--
LESS
llllll
Wi
--i-
2
.
.
ps
Fig. 75.-PELVIS OF DINORNIS (AFTER MIVART). NATURAL SIZE.
il, ilium ; P, pubis ; ps, interobturator process; lp, pectineal process.
with the ilium, and there is a greater or less connection
between the several bones. This is seen in a less developed
condition in the struthious birds and tinamous than in any
others. In the tinamous, in fact, the pubis and ischium are
quite free from each other distally, and from the ilium. In
the ostrich the pubes unite in a ventral symphysis ; in Rhea
there is a remarkable modification induced by the meeting
of the ischia. The details of the struthious pelvis will be
found described under the description of that group. In
carinate birds the ischium is for the greater part of its extent
fused with the ilium, a foramen only—the ischiadic foramen
-being left anteriorly. The pubes join to a less extent with
the ischia, and are sometimes (e.g. Colymbus) quite free
OSTEOLOGY
133
from them. The prepubic or pectineal process is large in
the struthious birds, in the tinamous, and in a few carinates,
such as Geococcyx. It has received much attention as the
possible equivalent of the reptilian pubis, the bird's so-called
pubis being in that case the homologue of the posterior pubic
process of the reptile. The dinosaurians seemed at one time
to have been the means of solving the questions involved ;
for in some of them there is a backwardly directed pubis,
not quite so bent as in the bird, from the anterior and upper
end of which a stout bone, considered to be the homologue
of the pectineal process, is directed forwards. This latter,
however, is clearly a part of the pubis, while the pectineal
process is at least not always a product of the pubis, being
sometimes purely iliac in origin, sometimes partly pubic and
partly iliac. It may be that the missing prepubic process of
the dinosaurian pelvis is represented by the remarkable
bones ankylosed to the ostrich's pelvis anteriorly, and con-
tinued forwards by a cartilaginous tract, which were dis-
covered by DARWIN and GARROD. This will reduce the
pectineal process to the level of a mere projection of the
pelvis of no particular significance save as a secure hold for
the important ambiens muscle which is there attached. In
any case it is safe to assert that wherever that process is pre-
sent and long the ambiens is also present and well developed.
Among carinate birds the pelvis does not show a great
variability of form. The pelvis is either broader or narrower,
being excessively narrow in the Colymbi. The proportions
of the preacetabular and the postacetabular regions also
differ, as do their relative breadths.
. It is noteworthy that the pubis is sometimes defective in
the middle, appearing then to consist of a proximal and
distal portion unconnected in the dry skeleton. The fact
also that but few muscles arise from the pubis seems to show
that it is in a condition of degeneration.
In Archæopteryx alone are the elements of the pelvis
not ankylosed together.
The acetabulum of all birds except Dromæus is perfo-
134
STRUCTURE AND CLASSIFICATION OF BIRDS
rated; but the perforation is reduced in size in Geococcyx,
Tinamus, and Hesperornis.
Hind Limb.-The hind limb of birds consists of femur,
tibia and fibula, tarsus, metatarsus, and phalanges.
In all birds the femur is shorter than the tibia, the pro-
portions varying much. It seems impossible to place those
birds in which the difference is least at the base of the series,
on account, of course, of a resemblance so far to reptiles,
since relative importance of the fore and hind limb appears
to have something to do with the matter. From FÜR-
BRINGER's tables ? it is to be gathered that Fregata is the
bird in which the difference between those two segments of
the leg is least. It is most pronounced in the divers, flamingo,
and Tubinares. A bone of some classificatory importance is
the patella, a sesamoid on the upper surface of the knee.
This bone is not ossified at all in Colymbus, but is enormous
in the grebes and in Hesperornis, in which latter, as in
Phalacrocorax and Biziura lobata, it is perforated by the
tendon of the ambiens. In Plotus the patella is grooved only
for this tendon.
In no bird (except as an occasional abnormality) is the
fibula a complete bone. It fails below, and does not reach
the tarsus. It is usually more or less coalescent with the
tibia. The latter is a strong bone with a crest in front, which
is enormous in the divers and Hesperornis. The distal end
of the tibia is formed by a portion of the tarsus, of which
the remaining portion is coalesced with the metatarsus. The
tarsus in the embryo 3 consists of three chondrites, a tibiale,
a fibulare, and a distale. The latter represents the separate
distal elements of the tarsus fused. The tibiale sends up-
1 KESSLER (* Osteologie der Vogelfüsse,' Bull. Soc. Nat. Mosc. 1841) has also
given tables. The value of the long bones' of the leg for defining orders,
families, and often genera' is plainly set forth in this paper. See also MILNE-
EDWARDS, Oiseaux Fossiles de la France, where further information is to be found.
2 J. KACZANDER, · Beitrag zur Lehre über die Entwicklungsgeschichte der
Patella,' Mt. Emr. Inst. Wien, (2) ii. 1887, p. 12.
3 G. BAUR, 'Der Tarsus der Vögel u. Dinosaurier,' Morph. J.B. viii. 1883,
p. 417; E. G. MORSE, "On the Carpus and Tarsus of Birds,' Ann. Lyc. New
York, x. 1873, p. 141, and on the Identity of the Ascending Process of the
Astragalus,' &c., Anniv. Mem. Bost. Soc. Nat. Hist. 1880.
OSTEOLOGY
135
11
wards an 'ascending process,' found also in the dinosaurs,
which is the equivalent of the intermedium, while the
.centrale is represented by a distinct osseous nodule in the
adults of the Struthiones (including Dinornis) and tinamous.
In Apteryx T. J. PARKER found two osseous centralia.
... The number of toes and phalanges has been already
described above.
... The Skull. While presenting many characteristic features
of its own, the skull in birds shows certain fundamental like-
nesses to the skull of the reptilią. ! As in them, and contrary
to what we find in the mammalia, the skull of birds-
1. Articulates with the spine by a single occipital
condyle.
2. Possesses a quadrate bone for the articulation of the
mandible.
3. The mandible itself is composed of at least a dentary
angular and articular portion.
4. The columella auris is very similar.
The bird's skull is, however, distinguishable by a namber of
characters, of which the following are the most important:-
... 1. The bones of the cranium are very closely united and
2. The brain case is large as compared with that of
reptiles.
3. The bones of the skull, as are those of the skeleton in
general, are light and contain air spaces.
4. The columella and the os transversum of the reptiles
are absent.
5. There is no distinct postfrontal.
The bones of the bird's skull, as that of other ver-
tebrates, may be distinguished into four categories-
(1) those of the cranium ossified from its cartilage ; (2) those
of the sense capsules ; (3) those of the visceral arches, and
(4) membrane bones connected with the several regions
enumerated.
| H. MAGNUS, · Untersuchungen über d. Struktur d. knöchernen Vogelkopfes,
Zeitschr. wiss. Zool. xxi. 1871.
2 See however below, under Passerine skull.
136
STRUCTURE AND CLASSIFICATION OF BIRDS
1. The bones formed by ossification from the chondro-
cranium are four occipitals, viz. basioccipital, two exoccipitals,
and the supraoccipital, forming a complete ring of bone
round the foramen magnum; basisphenoid, with two wings,
the alisphenoids ; presphenoid, with two wings, the orbito-
sphenoids (occasionally atrophied, e.g. Apteryx); meseth-
moid, with two lateral wings, the ectethmoids (sometimes
termed prefrontals); these are occasionally absent as distinct
ossifications, and may sometimes, on the other hand, be very
large and even appear on the frontal surface of the skull,
marking the orbit anteriorly; in those cases they take the
place of the orbital part of the lacrymal and have a better
claim to be called prefrontal.
2. The investment of the auditory capsule, termed
collectively the periotic bone, consists of three separate
elements, the prootic, opisthotic, and the epiotic, which last
is absent in the Apteryx.
3. The first visceral arch, the mandibular, has but two
bones 1 ossified from its cartilage, the quadrate and the
articulare of the lower jaw. The second and third arches
form the hyoid apparatus; the ossifications are, first, the
columella auris, a bone corresponding physiologically, if not
also morphologically, to the ear bones of mammals ; secondly,
a median piece in front, composed of two fused pieces, the
basihyal, with sometimes lateral processes, the ceratohyals ;
thirdly, the basibranchial, with two long lateral outgrowths,
of which the nearest regions are ossified to form the cerato-
branchials; thirdly, a single median piece (sometimes absent),
the urohyal, a remnant of the third arch.2
The membrane bones of the bird's skull are numerous,
and may be referred to the same categories as the cartilage
bones.
1. Associated with the cartilaginous cranium are pos-
teriorly the parietals; in front of these the frontals; with
the frontals articulate the lacrymals, of varying development,
A mento-meckelian has been recently discovered in hawks.
? For modifications of hyoids see especially GADOW, in Bronn's Thierreich,
and GIEBEL, Zeitschr. f. d. ges. Naturw., xi. 1858.
OSTEOLOGY
137
А
VM
same.com.mm.
and in the hawks bearing a second and separate bone
behind. These bones appear sometimes to have a definite
relation to the cartilaginous ectethmoids. I do not refer so
much to the fact that they sometimes entirely fuse with
them (and with the skull wall) às to the varying size and
relations of the two. In the kingfishers, for example, where
the ectethmoids are small, the lacrymals are large, and have
below an expanded plate which supplies the place of the
feeble ectethmoid. When the lacrymal does not reach the
orbital margin, as in Corvus, the
ectethmoid does, and, as it were, takes
its place. In many birds belonging C-
to quite different orders there is a
small bone connecting the lower end
of the lacrymal, or of the ectethmoid, 6m
with either the palatine or the jugal
bar; this bone has been termed os
crochu,' os uncinatum, os lacrymo-
palatinum, and will be described in
detail in those birds where it is to
be found.' It may be that the os
uncinatum should have been de-
scribed as one of cartilaginous bones
of the cranium. In some birds (tina- FIG. 76.—HYOID or Latha-
mous, Menura, Psophia, and Arbori-
horen US discolor (AFTER
MIVART).
cola) there is a set of supraorbital b, basihyal ; hb, hypobranchial ; cv,
bones margining the orbits above. entoglossum ; P, parabyal ; c, con-
The base of the brain case is protected
by a large basitemporal, which has sometimes (e.g. Apteryx)
a long rostrum in front. The maxillæ are sometimes sepa-
rate from each other, and at times united across the middle
line by more or less extensive ossifications, of which a pro-
minent one, and with the appearance of a separate bone,
is the maxillo-palatine. The premaxillaries in front of these
send back a long process extending as far as the nasals.
2. To this category, perhaps, belong the squamosal,
See under Cariama, Tubinares, Steganopodes, Musophagi, where cross
references will be found.

ceratobranchial; ,
rohyal ; e,
cavity in e.
138
STRUCTURE AND CLASSIFICATION OF BIRDS
referable to the auditory capsule, and the nasals above and
the vomers below to the nasal capsule. The vomers are
often paired bones, and near to them are other small and
independent ossifications, such as the septomaxillaries (see
under Passeres) and the mediopalatines (see under Cuckoos).
Connected with the eye--ossified, indeed, in the sclerotic-is
the sclerotic ring.
: 3. As membranous ossifications connected with or in
the neighbourhood of the visceral arches are the pterygoids
and palatines of the first arch, and perhaps the quadrato-
jugal and jugal, connecting the quadrate with the maxillæ.
The pterygoids are, as a rule, style-like bones, flat, however,
in the penguins, and may or may not articulate with the
basis cranii by means of the basipterygoid processes. The
palatines may be completely separate from each other, or
fused for a greater or less extent. They are broader or
narrower, as the case may be. The lower jaw has a number
of membranous ossifications; these are the splenial, dentary,
angular, supra-angular, and coronary. One or two additional
elements may be present.
With these general characters the skull of birds shows a
considerable number of differences of minor importance in
different families and genera. The first, perhaps, of these
in degree of importance-certainly in general estimation, if
not actually so-is the series of modifications of the avian
palate which were worked out in detail by HUXLEY, and
after him by PARKER, but which had been previous to
HUXLEY'S ? well-known paper studied with some degree of
success by CORNAY.
HUXLEY distinguished among the palates of birds the
following principal modifications :-
1. Dromcognathism.— This characterises not only the
ratites but also the tinamous, and has been indeed the
? In P. Z. S. 1867. See also paper by NEWTON, Ibis, 1868, p. 85, and reply,
ibid. p. 357.
? •Considérations Générales sur la Classification des Oiseaux,' &c., Rev.
Zool. Soc. Cuvierienne, 1847; see also HEERWAGEN, Beiträge 2. Keniti. d.
Kicfergaumenapparates d. Vögel, Diss. Inaug., Nürnberg, 1889..
OSTEOLOGY
139
principal reason for the close association of these birds by
subsequent writers. In these birds (see fig. 77) the vomer is
broad posteriorly, and thrusts itself between the pterygoids
and palatines on the one side and the basisphenoid rostrum
on the other, and thus prevents their articulation. This is
the typical dromæognathous state ; but there are certain
modifications which will be described in detail later. The
ostrich, for example, is only dromæognathous in that the
pterygoids and palatines do not articulate with the basi-
sphenoidal rostrum; for the vomer in this bird is short and does
not reach back far enough to prevent (so to speak) the union.
2. Desmognathism.-In a variety of birds belonging to
many orders the vom'er has either disappeared or is very
small; the two maxillo-palatine plates come into contact
in the middle line, as, indeed, they do in the dromæognathous
skull. As with all the types of skull to be enumerated, the
pterygoids and palatines at the point of their union with
each other articulate with the basisphenoidal rostrum. (This
kind of skull is illustrated in fig. 78.)
3. Schizognathism.—This type is almost as prevalent as
desmognathism. The vomer, well developed, terminates, as
a rule, in a point anteriorly. The maxillo-palatines, variable
in size and shape, do not meet across the middle line with
each other or with the vomer. (See fig. 79.)
:: 4. Ægithognathism. – Found typically in 'finches' and
in passerines generally; is very like the last type. The
distinguishing character (fig. 80) is that the vomer is
broad and truncated anteriorly, lying between the separate
maxillo-palatines. The skull is thus schizognathous'
etymologically. To these four divisions Professor PARKER
has added-
5. Saurognathism.—Exemplified in the woodpeckers.
The maxillo-palatines are extremely slight, hardly extending
inwards from the maxillæ ; hence the skull is widely
schizognathous. The vomers are delicate paired rods.
As stated in the foregoing brief epitome of the characters
of the several types of skull, the facts seem to differentiate
the five types fully. ELLIOT COUES remarks of desmo-
min.
140
STRUCTURE AND CLASSIFICATION OF BIRDS
gnathism that it does not fadge so well as any other one of
the palatal types of structure with recognised groups of
birds based on other considerations. This might be really
said of saurognathism also ; for the woodpeckers are not so
far removed from other picarian birds as the structure of


V
)
Pineau
MA!
!
Pmix.
(2x
STIU
lui
3
S2
SHO
.
ST
-
WE
Dop
Map
.
.
---
.
...
11
I
2
WA
who
SU
RSS
2L
.
Time
15.3.
ry
SU
w
re
Alitumi
my
f
.
.
ID
No
Fig. 77.-SKULL or Rhea. VENTRAL
VIEW. (AFTER HUXLEY).
Pm.t, premaxillæ ; Mxp, maxillo-palatine; R.
rostrum ; Vo, vomer; Pl, palatine; Pl,
pterygoid ; *, basipterygoid process.
Fig. 78.-SKULL or Dacelo (ATTER
HUXLEY).
Lu, lacrymal. Other letters as in previous
figure.
their skull would lead us to believe. Neither are any of the
subdivisions, except that of the dromæognathæ, really satis-
factory from the classificatory point of view. Their in-
efficiency, however, is rendered harmless by the fact that
OSTEOLOGY
141
they are in reality not such hard and fast distinctions as
might be gathered from the foregoing abstract and from
textbooks in general.
PARKER has distinguished four categories of desmo-
gnathism-(a) perfect direct, the maxillo-palatines uniting
below in the middle line ; (6) perfect indirect, maxillo-
palatines separated by a chink in the middle line ; (c) im-
perfectly, direct, maxillo-palatines sutured together in the


Prix
(DC
ES
!
..
AL
MCP
ES
1134
A
LLT
g
RA
le
VA
12
W
87
II.
www
DS
...
IN
Fig. 79.-SKULL OF Alca (AFTER HUXLEY).
*, prefrontal (ectethmoid); Qu, quadrate ; Mix,
Maxilla. Other letters as in previous figures.
Fig. 80.--SKULL Or Corvus (AFTER
HUXLEY). LETTERING AS BEFORE.
U
middle line; (d) imperfectly indirect, maxillo-palatines closely
articulated with and separated by the median septomaxillary.
There is also the exaggerated desmognathism ( double des-
mognathism ') of the hornbills, &c., where not only the
maxillo-palatines but also the palatines are united across the
middle line; and finally the spurious desmognathism of
certain ægithognathous birds (Megalæma), in which the
142
STRUCTURE AND CLASSIFICATION OF BIRI)Ş
CU
vomers are ægithognathous, but the maxillo-palatines are
united.
As of desmognathism so of ægithognathism, PARKER
distinguishes four kinds-
Incomplete ægithognathism (Hemipodes) is distinguished
by the fact that the broad double vomer has a septomaxil-
lary at each angle, which is only “strongly tied' to alinasal
cartilages.
Complete Var. 1.—The vomers are distinct from the often
long alinasal walls and turbinals : a small septomaxillary
appears on the angle of the alinasal cartilage, but does not
run into it.
Complete Var. 2.--Here the vomers are grafted upon the
nasal wall.
Compound, where in an ægithognathous palate desmo-
gnathism is produced by ankylosis of the inner edge of the
maxillaries with a highly ossified alinasal wall and nasal
septum.
Among the higher families the septomaxillaries are often
absent.
It is clear, therefore, that a very narrow boundary line
separates desmognathism in some of its forms from schizo-
gnathism, and that there is a direct relationship between
desmognathism and ægithognathism. The only type of
skull which is really distinct is the dromæognathous.
In classificatory importance perhaps next comes the
condition of the nasal bone. GARROD distinguished birds
into those with holorhinal and those with schizorhinal
nostrils. These terms refer to the posterior edge of the bony
nostril, which in one set of birds, the holorhinal, ends behind
with a clear oval outline (fig. 81), or in the schizorhinal
birds runs back as a gradually narrowing chink; this latter
arrangement is shown in fig. 82. In the holorhinal bird a
straight line, drawn across the face from the posterior
boundary of one nostril to that of the other, passes in
front of the termination of the nasal processes of the
prernaxilla. It is not always the case that a line drawn
similarly to that of the holorhinal birds passes behind the
OSTEOLOGY
143
end of the premaxillary process, but it is generally so. In
the schizorhinal skull it often appears, as in the typical
schizorhinal cranes and charadriiform birds, as if the outer
part of the nasal bone were a distinct bone; for it joins the

ul.
1
OUI
ISNO
int
.
win
i
-
TI
.
I
**
WIRA:
Virit
tit
!!
*
AM
-Tuil
.
RO.
it
lo
AU
.
)
.
FIG. 8.1.-SKULL OF Psophia. LATERAL VIEW. (AFTER BEDDARD.)
inner lamina at an angle. In the typical holorhinal skull,
on the other hand, as, for example, in the Rallidæ, the two
parts of the nasal come smoothly together, leaving the clear-


AR KIRMI
.
www
2
TOON
.
SY
FO
TI
AW
WC
P7
VP
OLY
AZ
VA
XXS
wa
16
TO
Se
FIG. 82.-SKULL OF Larus.
DORSAL VIEW. (AFTER
GARROD.)
Fig. 83.–SKULL OF Furnarius.
DORSAL VIEW. (ALTER
GARROD.)
cut, ovally contoured nostril. It is not, however, always easy
to distinguish so clearly as can be done between Rallus and
Grus. Thus Garron admits the schizorhiny of Furnarius
144
STRUCTURE AND. CLASSIFICATION OF BIRDS
and some other Passerines, in which the bony opening of
the nostrils, although, as he figures it, rounded off at its
termination, ends behind, or at least on a level with, the
ends of the nasal processes of the premaxillæ. In the same
way an intermediate condition is offered by Thinocorus and
Glareola, in which there is much the same kind of arrange-
ment. But one of the most striking instances which have
come to my personal knowledge is that of Chunga. Its
near ally Cariara is, as correctly stated by GARROD and
others, holorhinal, which in view of its relationship to the
cranes is unfortunate. But in Chunga it is clear that the
holorhiny is secondary, being produced by a slight modifica-
tion of schizorhiny.
A careful examination of Chunga shows that the two
parts of the nasal bone do not join evenly above the opening
of the nostril, but that the outer descending lamina of the
bone is divided for some little distance by a crack from the
premaxillary portion, the two running up in close contact-
so close that no actual space is left between them, only a
line of junction to mark their original separateness. In the
skulls of Cariama that I have examined there is no trace of
this; but, considering the nearness to each other of the two
birds, it seems probable that it is merely disguised. This
fact favours FÜRBRINGER’s idea that schizorhiny is more
primitive than holorhiny, and is so far adverse to GARROD'S
view that the schizorhinal disposition is most certainly one
which is a secondary development upon the normal holo-
rhinal nares.'
It is clear too that the holorhiny of such a bird as Opis-
thocomus, where the ossified alinasals produce the rounded
margin of the bony nostril, cannot be accurately compared
with the holorhinal nostril of a gallinaceous bird, where it is
the nasals themselves that bound the orifice.
The presence or absence of basipterygoid processes is
another matter upon which some stress is usually laid from
a systematic point of view. One assumes that the existence
of these processes is the original condition and that their
OSTEOLOGY
145
processes is most capricious. Thus among the limicoline
series they are absent from the skulls of the gulls and-more
unexpectedly perhaps—from the Edicnemidæ and Thino-
coridæ. Among the birds of prey the secretary bird and
the American vultures have these processes, while the
Falconidæ have them not. The goatsuckers may be
similarly divided into those without and those with basi-
pterygoid processes. The TUBINARES, again, show variation
in this respect, as do the trogons. It is therefore, in the
first place, impossible to compare directly all birds which are
without these processes, just as it is impossible to put
together all birds without an ambiens. We may note, how-
ever, that it is only among groups of birds which show a
considerable range of structural variation that there is this
variation of the basipterygoid processes. It is not, so to
speak, lightly that they have gone. The reason for the
assumption that the basipterygoid processes are primitive is
their existence in reptiles and in such widely separated types
as chameleons, pterodactyles, and Hatteria, and in addition
I may point out that there is a significant correspondence
between a primitive arrangement of gut and the presence
of these structures. It cannot be said that every bird with
basipterygoid processes has the most primitive arrangement
of gut, but we do find both in the ratites, Chauna, the
gallinaceous birds, the charadriiform birds, the owls, and
the goatsuckers. The falconiformes (Haliaetus) are, it is
true, an exception; but it must be remembered that this
group is one that has basipterygoid processes (Serpentarius,
Cathartes), though they are absent in the true falcons.
The principal variations exhibited by the cranium of
birds, apart from those that have been already considered,
concern the existence of supra-orbital bones, the existence or
non-existence of occipital fontanelles, the marks of the supra-
orbital glands, and the presence or absence of a hinge line
between the skull proper and the face.
The existence of supra-orbital bones in the form of a
longer or shorter chain of ossicles was first pointed out by
PARKER as a reptilian character of occasional occurrence.
146
STRUCTURE AND CLASSIFICATION OF BIRDS
.
.
.
1S
ONE
.**.
SaaS
SUB
27
.
19
:
ult
LE
REC
Hr
.
DIN
.
NIS
In the tinamous there are a series of these bones, which in
Psophia are reduced to a smaller number, and in the passe-
rine Menura to three only; on the other hand in Perdix
they are again more numerous. It is possible that in such
birds as Rhinochetus and Edicnemus, in which the edge of
the bony orbit is very sharp, the thinness of the edge is due
to the fusion of a set of these bonelets with the true margin
of the frontal. As will be seen, the existence of these bones
is so rare as to render them of not great service from a sys-
tematic point of view; but it is only
among birds which may be fairly
on other grounds regarded as
archaic that they are to be met
with.
The occipital fontanelles (fig.
84) are mostly developed in water
birds, though any connection be-
tween them and the habit of the
birds is at least not obvious. They
FIG. 84.-SKULL OF Chloephaga are most general among
Magellanica. BACK VIEW.
the
(AFTER GARROD.)
Limicola and the duck tribe, but
are found also in the Plataleidæ
and exist temporarily in the gulls; they are also found in
the flamingo, Gruidæ, and among the auks.
Almost the same remarks may be made of the impressions
for the supra-orbital glands. They are very marked in the
Limicolæ, being more usual than the occipital fontanelles ;
they are met with in the auks, divers, and penguins; in the
cranes and Plataleidæ they are present, but not so conspicuous.
The hinge line between face and skull is seen in its most
fully developed condition in parrots, where the face is actu-
ally movable on the head. But it is commonly met with
elsewhere, particularly among the Anomalogonatæ; it is
associated with holorhiny and with comparatively short
nasal processes of the premaxillary.
Apart from their relations to the vomer the palatines and
pterygoids show some variations in structure. As to the
pterygoids, the most prominent difference concerns the place

OSTEOLOGY
147
TI
where the articulation with the basipterygoid facets occurs ;
it is usually towards the middle of the bone; but in the emu,
in the Anseres and Galli it is quite at the end of the bone,
the end nearest to the palatines. The palatines differ greatly
in shape and in breadth. Among the Anseres and Galli the
internal lamina which meet in the middle line above the
basisphenoids are practically absent, being only represented
by a more or less faintly marked ridge. In other birds these
regions of the palatines are well marked, and may meet for
a considerable space in the middle line, and, as in Steatornis,
an anterior portion of each bone may come into contact in
the middle line further forward, thus giving rise to what has
been termed double desmognathism, the maxillo-palatines of
course forming the other junction in the middle line in front
of them again. In most birds perhaps the palatines are
gradually rounded off behind, but in the Ardeidæ and in
Rhinochetus, &c., they are as it were sharply cut across
behind this edge, being at right angles to the long axis of the
bone. In many Passeres and in some other birds there is a.
well-developed postero-lateral process of the bone, which has
been termed transpalatine; this, if it came into contact with
the jugal arch, as it nearly does in some Passeres, would bear
the strongest likeness to the transverse bone of reptiles..
The palatines are occasionally, but rarely, fenestrate, e.g.
Anous, Eurypyga.
The vomer varies from complete absence (Colius) to very
striking presence. When present there is every grade be-
tween a thin splint and a broad flat bone, which in the latter
case is often obviously formed of two lateral halves. These,
however, do not appear to remain completely separate except
among the Pici (q.v.), where they are smallish splints. But
not only among the ostrich tribe, but in Hesperornis and
passerines the vomers are double in the young. A series of
small bones lying between the palatines, and called interpa-
latines and septo-maxillaries by PARKER, may be regarded
as belonging to the vomerine series. They are unpaired
ossicles which continue, though with a hiatus, the vomer
backwards.
L
!
L
2
148
STRUCTURE AND CLASSIFICATION OF BIRDS
D
The degree of development of the lacrymals and the
ectethmoid processes varies greatly among birds, and is at
times of use for systematic purposes. In some birds, as, for
example, among the cranes, there is no junction between
those bones; in the Charadriidæ, on the other hand they
form a complete ring; in Pterocles, &c., the two are firmly
blended into a square plate of bone which bounds the orbit
anteriorly.
The lacrymal is occasionally joined to the palatine or to
the jugal by a small independent ossicle, which PARKER has
termed the uncinate bone, and thinks to be the homologue
of the anterior connection of the palato-quadrate arch with
the skull in the tadpole, &c. This bone is so variable in its
presence (e.g. Cariama, Tubinares) that it can hardly be
regarded as of much systematic importance. The last matter
to which we may refer as of classificatory importance is the
form of the quadrate, which Miss WALKER has shown to
vary much and characteristically in different groups. It had
been long known that the single-headed articulation with
the skull was a character of struthious birds, excepting
Apteryx, and of Ichthyornis, and to a less extent of gallina-
ceous birds and ducks.
· The value of the base of the skull in classification has
been continuously debated since the facts were first so clearly
set forth by HUXLEY.
From the complications introduced into the originally
simple series of modifications of the skull instituted by
HUXLEY, by PARKER, and from the varied criticisms of fact
and conclusion of a classificatory kind based upon fact, we
may disentangle one conclusion that many ornithologists
will agree with that is, the more lacertilian character of
the skull in the struthious than in other birds. In them the
palatines are borne off from the basisphenoidal rostrum by
the vomer (with the exception of Struthio, in which, however,
the palatines are still remote from the rostrum), and the
general disposition of these parts is, as HUXLEY wrote, “more
lacertilian than in other birds.' Furthermore in the stru-
thious birds the double character of the vomer is more
OSTEOLOGY
149
universally retained than in other birds. As T. J. PARKE I
has shown in Mesopteryx, Anomalopteryx, and (according to
OWEN) Dinornis torosus, and finally in the young of Emeus
crassus, there are distinct paired vomers. The strong anterior
and posterior bifurcation of the vomer in living Struthionidæ
is an indication of the partial fusion of the primitively.
separate halves of the single vomer. A double vomer,
however, is not a feature of the struthious birds alone; in
the young Hesperornis the same occurs; in the woodpeckers
(hence Saurognathæ in PARKER'S nomenclature) there are two
distinct vomers, while PARKER has recently committed him-
self to the general statement that 'in most birds that have
a large or wide vomer it is double at first. The inference
is that the single thread-like vomer of many birds is in a
degenerate condition. In any case a large vomer, double or
single, and a lacertilian palate generally mark all the stru-
thious birds, and justify their generally recognised position
somewhere not far from the root of the avian series.
As for desmognathism and schizognathism, Professor
PARKER has aptly remarked : ' The use of such a taxonomic
character as desmognathism or schizognathism is very
extensive in some groups and very limited in others; and
there is no sharp line of demarcation between the two. The
most lacertilian palate for openness is that of the woodpecker ;
the most modified by intense ossification is that of the
'toucan; yet these two types, each specialised to the utter-
most, have a postcephalic skeleton, not indeed identical, but
extremely similar.
That the toucans and woodpeckers are exceedingly near
akin is also shown by many other features of their organisa-
tion (see below). HUXLEY claimed for his Schizognathæ
that they were a natural group, but hardly claimed so much
for the Desmognathæ. He admitted, however, that Cariama,
a schizognathous bird in the totality of its organisation, had
a palate approximating to the desmognathous. The Cracidæ
and Rhinochetus are in the same anomalous position. The
Trogonidæ, whose nearest allies are the desmognathous
birds, have a schizognathous palate (as was pointed out by
150
STRUCTURE AND CLASSIFICATION OF BIRDS
FORBES), while the goatsuckers show both desmognathism
and schizognathism among the members of the group. On the
other hand schizognathism is not on the taxonomic side
sharply marked off from ægithognathism. HUXLEY's defi-
nition of the vomer in schizognathous birds was that it is
pointed in front;' this is not the case with many Schizo-
gnathæ, e.g. Hematopus, Numenius (cf. below). And, on the
other hand, PARKER showed that another peculiarity of the
ægithognathous skull, the union of the vomer with ossified
alinasals, was also found in the 'Turnicomorphæ,' a group
which for other reasons should be placed among HUXLEY'S
Schizognathæ..
It appears, therefore, undesirable to lay too much stress
upon the modifications of the palate, as seen in the three
groups just discussed, as a basis of classification.
HUXLEY defined desmognathism as follows: "The
vomer is often either abortive or so small that it disappears
from the skeleton. Where it exists it is always slender and
tapers to one point anteriorly. The maxillo-palatines are
united across the middle line either directly or by the
intermediation of the ossifications on to the nasal septum.'
This definition applies perfectly well to the Anseres and
Palamedeæ, but not to all other groups of birds.
But there is the form of desmognathism found in the
Steganopodes and in the owls and Accipitres. In the
former group there is no desmognathism in the sense of
HUXLEY) except in Pelecanus. The maxillo-palatines of
Phaethon and Fregata (see below) are perfectly free; in
front of them the palate is complete, but that completeness
is formed by a union of lateral extensions of the maxillæ
which are distinct from the rounded maxillo-palatines. In
the cormorant, which is admittedly an ally of Phaethon, there
appears at first sight to be a true desmognathism, a fusion,
that is to say, of the maxillo-palatines. The plates of bone
in question are beneath the ends of the palatines, but, instead
of running horizontally in the same plane as the palatines,
they run obliquely upwards (when the skull is regarded from
below). If it were not for Fregata, these bones might be
OSTEOLOGY
151
IP
looked upon as the homologues of the maxillo-palatines of
Phaethon. But in Fregata both structures are present.
Coexistence clearly disproves homology; we must, therefore,
place the desmognathism of Phalacrocorax upon an
entirely different footing from that of the Anseres, where
the maxillo-palatines unite in the typical fashion across the
middle line.
In addition to these forms of desmognathism it appears
to me that we should distinguish that of the American vul-
tures, where there is no union at all of the maxillo-palatines,
but only of the alinasals.
• In fact there appear to be three ways of bridging over the
palate which may be termed desmognathism, though the
word becomes merely descriptive of a condition and not
necessarily indicative of affinities; these are-
(1) Union of maxillo-palatines (more or less complete).
(2) Union of alinasals.
(3) Union of maxillæ in front of the maxillo-palatines.
These three are usually combined in various ways; e.g.
In hornbills there are all three methods of union; in
some Steganopodes only numbers 2 and 3.
Brain and Nervous System.
The brain of recent birds chiefly differs from that of
reptiles by the large size of the hemispheres, the large size
of the cerebellum, and by the fact that, owing to the great
development of these two regions, the optic lobes are pushed
to one side. T. J. PARKER found in studying the develop-
ment of Apterys that the latter feature is acquired during
development, and that the optic lobes have originally the
reptilian position. The extinct cretaceous birds had brains
with smaller cerebral hemispheres and with larger optic lobes
than existing birds, and were in these particulars more repti-
lian. On the other hand, if the cast present in the London
example of the Archæopteryx be really, as it was first surmised
to be by Sir JOHN EVANS, the brain of the bird, it was less
reptilian than Hesperornis, a fact which may possibly
152
STRUCTURE AND CLASSIFICATION OF BIRDS
suggest the inference that the brain of the cretaceous bird
furnishes an example of degeneration rather than of the
retention of an archaic character.
The hemispheres, although smooth in the majority of
birds, show faint indications of what may correspond to
furrows in some others. In the duck, for example, as
figured by GADOW (after BUMM), there is a central raised area
marked off by a furrow from the surrounding parts of the cere-
brum ; faint traces of the same occur in Buteo vulgaris. The
weight of the brain as compared with that of the whole body
has been studied by several observers, and according to their
results the Passeres and parrots take the highest place.
But GADOW justly remarks that 'the attempts to sort birds
according to the proportion of brain to body have led to no
practical results, chiefly because the variable conditions of
fat and lean subjects have not been considered.'
The brachial and lumbar plexuses, particularly the
former, have been studied in a large number of birds ;
FÜRBRINGER has published a quantity of drawings of the
former, but no classificatory results of reliability appear to
follow from the facts collected with so much diligence. The
brachial plexus varies in position and in complexity. The
former variations are largely correlated with the varying
length of the neck; thus in Columba the first spinal nerve
entering into the plexus is the tenth, in Phænicopterus the
seventeenth. The number of nerves which together form
the plexus varies from only three in Bucorvus to six in
Columba.
The Eye.—The eye of birds presents many resemblances
to that of reptiles. The minute structure of the retina
presents many points of similarity, as also the ring of ossifi-
cations in the cornea, and the pecten. The latter is a folded
process of pigmented tissue which projects into the vitreous
humour through the choroidal fissure, which is in the embryo
the gap left between the edge of the optic cup and the lens
on one side. The pecten offers differences in various birds
upon which perhaps some little stress can be laid. In
Aptery. it is entirely absent. There are very few folds in
BRAIN AND NERVOUS SYSTEM
153
the owls (4 to 7) and in the goatsuckers ; this might lead, in
connection with the total absence of the pecten in Apteryx,
to the conclusion that the less or greater development of the
organ had some relation to nocturnal or diurnal habits.
But the existence of only four in the emu seems to throw
some doubt upon this suggestion. Among the passerine
birds the largest number (raven 30) of folds in the pecten
is found.
Certain small ossifications in the cornea near to the
entrance of the optic nerve seem to be peculiar to the
Passeres and to certain picarian birds. The eyes have both
lacrymal and Harderian gland; the eyeball is moved by four
recti and two oblique muscles; the membrana by two
muscles, the quadratus and the pyramidalis, both innervated
by the sixth cranial nerve.
The Ear:-Birds have no external ear (concha), but in
many a flap forming a valve projects into the meatus from
the outer margin, a state of affairs which recalls the condi-
tions found in the crocodile. This outer ear is especially
well developed in the owls, in which birds also the ear region
of the skull is often markedly asymmetrical.
The inner ear has the three semicircular canals of all
higher vertebrates, but the cochlea is not coiled. The audi-
tory ossicles consist of a single structure, partly bony and
partly cartilaginous, called the columella.
The Affinities of Birds
In considering the relationship of birds to other verte-
brates .it is probably safe to leave out of consideration the
marnmalia and the amphibia. Points of likeness have, it is
true, been urged in favour of the latter view of an affinity
between birds and amphibia by the late Professor PARKER;
but apart from warm-bloodedness and the resemblance
of some of the more simple forms of feathers to hairs
there is nothing to be said on behalf of a kinship
between birds and mammals. As to the likeness with
amphibians, it is possible that the divergence of birds from
154
STRUCTURE AND CLASSIFICATION OF BIRDS
the reptilian stem was at a time when the characters of the
amphibian had been incompletely thrown off, and at a time
also when the mammals diverged on their own path from a
point near to that whence the birds took their origin. The
general belief is in the origin of birds from somie reptile stem,
but there is not an absolute agreement as to precisely which
group of reptiles birds are most nearly akin to. The researches
of MARSH and HUXLEY, besides those of COPE, SEELEY,
HULKE, and some others, have led to a general acceptance of
a nearer kinship with the dinosaurs than with any other
group of reptiles. In considering the question, then, which
forms the subject of the present chapter, we shall commence
with the dinosaurs. The dinosaurs, ranging in size from
vast creatures of 70 or 80 feet in length to a diminutive reptile
half the size of the domestic fowl, are first known from
the Trias, persisted though the Jurassic and finally came to
an end in the Cretaceous epoch, later than which no
remains have been found. So far as we are aware birds
came into existence in the Jurassic period; hence there is
no anachronism in considering them from the dinosaurian
aspect.
It was formerly held that birds antedated the Jurassic
period; for some of the celebrated tridactyle footprints in
the sandstone of the Triassic period were put down to birds.
It seems, however, to be now fairly certain that those foot-
prints are of dinosaurs. Still with so specialised a form as
Archæopteryx certainly was, and as Laopteryx probably was
in the Jura, it would not be surprising to meet with genuine
avian remains in the Trias. But even then there are
undoubtedly dinosaurs belonging to that period, so that the
question of relationship would resolve itself into a common
origin, not a derivation of birds from dinosaurs.
The part of the skeleton in which most resemblance is
shown between birds and dinosaurs is the pelvis. The
dinosaurian pelvis consists of apparently three elements, like
that of birds, but the pubis is an L-shaped bone, constructed
of two pieces, one directed forwards and the other back-
wards and parallel with the ischium of its side. The latter
THE AFFINITIES OF BIRDS
155
AL1
LI
1
is generally regarded as the homologue of the pubis of birds,
while the forwardly directed half of the bone is considered
to be the equivalent of the pectineal process. The alterna-
tive is to look upon the prepubis of the dinosaur as the pubis
of birds, and the postpubis as having disappeared altogether
in them. In this case the crocodile will be an intermediate
form ; for in this reptile the prepubis is the 'pubis,' while
the postpubis is represented by an inconspicuous process
upon the pubis. The former alternative commends itself to
us. There are birds in which the pectineal process is
practically absent; in others, as Apteryx, Geococcyx, &c., it is
large ; on the other hand there are dinosaurs, e.g. Laosaurus
Consors, in which the prepubis is generally reduced—to a
length of not more than one-third of the postpubis (pubis
of birds). The opposite extreme is reached by Triceratops,
where it is the postpubis which is less than a third of the pre-
pubis, and Ceratosaurus, where it is even further reduced.
It is not, however, only in the pubes that the pelvis of
the dinosaurs is like that of birds. In those reptiles the ilia
were extended forwards and backwards, as in birds, and in
Ceratosaurus at any rate the three bones were all firmly
ankylosed, as, in all birds save Arch@opteryx, where the
separation of the bones conforms to what is found in the
vast majority of the dinosaurs. Laosaurus, which has just
been mentioned, is one of the most birdlike of dinosaurs.
"The two species of the genus first described by the writer,'
remarks Professor MARSH, show these avian features best
of all, and it would be difficult to tell many of the isolated
remains from those of birds.' Of the cretaceous dinosaurs
the same author observes, · Others were diminutive in size,
and so birdlike in form and structure that their remains
can be distinguished with difficulty, if at all, from those of
birds.' Ornithomimus, as its name denotes, is one of those
especially annectent dinosaurs. In this genus the third
metatarsal is crowded backwards behind the second and
fourth, as in many birds. But the dinosaurian metatarsals
which are most strikingly like those of birds are of Cerato-
saurus, which MARSH has figured side by side with those
VI
156
STRUCTURE AND. CLASSIFICATION OF BIRDS
of a penguin, where the bones show greater traces than
in any other birds of their distinctness, and are furthermore
shorter than is the rule. In dinosaurs generally those bones
are separate, but not in Ceratosaurus, where the degree of
fusion is almost exactly that of Aptenodytes.
Furthermore in some dinosaurs, as in birds, the inter-.
medium is prolonged upwards as the ascending process of
the astragalus.
The proportions of the long bones of the hind limb are
distinctly birdlike in some dinosaurs. In Laosaurus, for
example, the femur, as in birds, is shorter than the tibia, the
reverse occurring in most forms. In the same animal and
in others the fibula is commencing to degenerate ; it is
decidedly smaller than the tibia.
In their skulls the dinosaurs show no marked approxima-
tion to birds; there are nevertheless one or two features
which may be remarked upon in this connection. The
earliest known forms from the Trias have perhaps the most
birdlike forms of skull. MARSH comments upon the light-
ness and avian appearance of the skull of Anchisaurus; it
has moderately developed basipterygoid processes instead of
those of such great length that are apt to characterise the
dinosaurs. The great extension backwards of the premaxil-
laries in some dinosaurs is an avian characteristic; this is
seen especially well in Diplodocus and Claosaurus. In the
former animal, as in some others, the two vomers diverge
widely posteriorly, as in many birds; and in the restoration
of the under surface of the skull in this dinosaur the vomers
have a very birdlike appearance.
Finally the height at which the transverse processes of
the vertebræ are borne seems, as HUXLEY has pointed out,
to suggest birdlike respiratory organs, while the hollowness
of many of the bones in many dinosaurs points in the same
direction. It is, however, undoubtedly in the pelvis and
hind limb that the most striking likenesses to birds are
shown by the dinosaurs. It has been attempted to put this
down merely to bipedal progression. It may be said,'
remarked Professor HUXLEY, “that all birds stand upon
ni
THE AFFINITIES OF BIRDS
157
their hinder feet, and that, as the Ornithoscelida did the same,
the resemblance of structure arises from a resemblance of
function. But I doubt if the majority of the Dinosauria
stood more habitually upon their hind limbs than kangaroos
or jerboas do; and, unless there was some genetic connection
between the two, I see no reason why the hind limbs of
Ornithoscelida should resemble those of birds more than they
resemble those of kangaroos. In addition to this it may be
pointed out that Hallopus, which appears to have been very
probably a leaping dinosaur, has not the specially ornithic
form of limb; it has large pubes and no postpubes.
A recent description by Mr. E. T. NEWTON of the skull,
brain cast, and cast of the auditory organ in a pterodactyle,
Scaphognathus Purdłoni, shows certain most interesting
resemblances between the pterosaurians and birds. It is
possible that this pterosaurian, like Pteranodon, possessed a
horny beak and no teeth. But the presence or absence of a
beak or of teeth is no more distinctive of birds (cf. Archæo-
pteryx) than of reptiles. The skull shows more positive
points of likeness. In the first place, the bones of the
Pterodactyle cranium are early ankylosed and well anky-
losed, being in this particular avian and not lacertilian.
The large size and backward extension of the single pre-
maxillary bone (=two fused premaxillæ) agree with that of
birds and contrasts with that of lizards. The palate shows
also certain interesting resemblances, more especially to
both emu and cassowary. As in the struthious birds and in
lizards also the palatines are borne off from the middle line
by the pterygoids; the latter bones, moreover, as in the emu,
articulate at their posterior ends with both quadrate and
basipterygoid processes. The vomer too is birdlike in being
pushed backwards, owing to the extent of the premaxillæ,
and in being thin, apparently single and bifurcate posteriorly.
Other general resemblances in the skeleton are the develop-
ment of air cavities in the bone, the large size of the orbit
—which may, however, in the pterodactyles have had some
1On the Skull, Brain, and Auditory Organ of a New Species of Pterosaurian,'
Phil. Trans. 1888, B, p. 503.
158
STRUCTURE AND CLASSIFICATION OF BIRDS
relation to nocturnal habits—and the presence of a keel upon
the sternum.
It is possible, though far from certain, that Scaphogna-
thus had not that characteristic reptilian bone, the os trans-
versum.
Finally, the general shape of the scapula and the angle
that it makes with the coracoid are birdlike in the pterodac-
tyles.
The brain of the pterodactyles seems also to have pre-
sented avian characters ; the optic lobes are pushed aside by
the large cerebellum, which had well-developed floccular
lobes. In the reptile's brain the optic lobes intervene
between the cerebrum and cerebellum.
The pelvis of the pterodactyles has some likenesses to
that of birds. The ilium has an extension in front of as well
as behind the acetabulum; and, if the opinions of SEELEY
are to be agreed to, there is a rather backwardly directed
pubis, more or less fused with the ischium, and a long and
thin forwardly directed piece, the prepubis of dinosaurs and
the pectineal process of birds.
The main difficulty, however, in the way of comparing
pterodactyles and birds is in the fact that both can fly, and
that each has acquired the power of flight by a different
method. Having acquired the power of flight it seems clear
that certain of the points of resemblance between them may
easily be due to that mode of life and may have been inde-
pendently arrived at.
159
THE CLASSIFICATION OF BIRDS
PROFESSOR NEWTON'S article “Ornithology' in the 'En-
cyclopædia Britannica,' and the preliminary sketch of Dr.
Gadow in Bronn's Thierreich,' contain a digest of, and
criticisms upon, the main schemes of classification of this
group which have as yet appeared. I shall, therefore, refer
the reader to those works for the history of the subject.
There can be no question, in my opinion, that birds must
be primarily divided into two great divisions, viz. Saururæ
and Ornithuræ, the first to contain Archæopteryx and possibly
Laopteryx, the latter the rest of birds, both living and extinct.
As to the Ornithuræ, while there is a very general agreement
with the main subdivisions-no one probably will quarrel
seriously with the divisions adopted in the present work-
no one has (to my mind) satisfactorily arranged the different
groups with reference to each other. More especially does
it appear to me that the majority of ornithologists are in
error concerning the position of the picarian and passerine
birds.
In considering a scheme of classification it is clear that
we must bear in mind. indications of the descent of birds.
Existing schemes have savoured too much of a mere sorting
by combining in various ways characters which are dis-
tinctively bird characters. However unsuccessful the con-
struction of phylogenetic trees has been, it is abundantly
plain that that must be the line to take in arranging a group
scientifically. It follows, therefore, that in sketching, at
any rate, the main outlines of our scheme attention must
be paid only, or chiefly, to those characters which birds
have inherited from their reptilian ancestors.
160
STRUCTURE AND CLASSIFICATION OF BIRDS
Now this at once lands us in a difficulty, which has been
too lightly regarded by many systematists. Phylogenetic
schemes used to be boldly linear, and even so recently as
the attempt of FÜRBRINGER the family tree savours a little
too much of the linear arrangement. Now the imperfect
remains of birds that have come down to us from tertiary
times show that the modern types of birds were fully
differentiated even then in addition to a few extinct forms,
such as Odontopteryx toliapicus (if this be not a steganopod).
But beyond that point there is the most scanty record of
bird life, limited to the Cretaceous Ichthyornithidæ and
Hesperornithidæ, with a few obscurer forms, and to the
Jurassic Archceopteryd. So emphatically were all these
creatures birds that the actual origin of Aves is barely hinted
at in the structure of these remarkable remains. Moreover,
at least in the case of Ichthyornis, they depart fully as
widely from any bird with the required' mixed' characters
as any living group, while Hesperornis can with safety be
relegated to the neighbourhood of the existing divers. We
get, therefore, no help whatever from the Cretaceous birds,
and, if any, only the scantiest assistance from Archcopteryx,
in determining what are archaic characters in birds. There
are no criteria by which we can assert with any degree of
safety the relative positions of this and that existing group ;
nor has the study of the comparative embryology of birds
as yet advanced sufficiently far to give any results, except
in isolated characters; such indications are the relatively
primitive character of the, basipterygoid processes, at least
in certain groups; for the gulls which are without them
when adult, have them as young chicks, as have in the
adult condition most of their near allies, the Limicolæ. It
may, therefore, so far be inferred that the gulls are a
modification of the limicoline type and not vice versa.
It would be perhaps held that any type in which a
number of undoubtedly reptilian characters had survived
would be on a lower level of organisation than other types
in which fewer or no such characters could be discovered.
But the few specially reptilian features in the organisation
-
THE CLASSIFICATION OF BIRDS
161
of birds have, so to speak, been distributed with such exceed-
ing fairness through the class that no type has any great
advantage over its fellows. PARKER has collected together
some of the reptilian survivals, and to his series a few others
may be added. The rudimentary organ of Jacobson found
by T. J. PARKER in Apteryx is a suggestion of the reptile ;
but we do not know enough about the development of other
birds (except the struthious, where PARKER found the same
rudiments himself) to lay much weight upon the discovery
as indicative of the low position of Apteryx in the avian
system. The supra-orbital chain of bones is also on the
same grounds an archaic character; but they exist in
such widely different types as tinamous, Psophia, Menura,
and quails. The double vomer is reptilian; this bone is
double or nearly so in struthious birds, in Hesperornis,
woodpeckers, and even in passerines and other types with a.
broad vomer. PARKER has compared the 'os uncinatum"
with the anterior suspensory cartilage of the tadpole's jaw
apparatus; this is found in so many and such various forms.
as Cariama, Fregata, Tubinares, Musophagidæ, Steatornis,
&c. Basipterygoid processes are distinctly reptilian, found
as they are in so many forms of reptiles. But among birds
they occur in nearly every big group, and are therefore most.
undistinctive. The pectineal process, if it is invariably—as.
T.J. PARKER says it is in Apteryx—the joint product of pubis.
and ilium, is not exactly comparable to the supposed corre-
sponding process of the dinosaurian pelvis; but in any case it is
found in Geococcyx and some other birds far away from the
Struthiones and the tinamous. A large number of vertebræ
in the tail is reptilian; but not only Archæopteryx but also
the swan has a long tail. Opisthocoelous vertebræ are.
found in the Alcæ, penguins, and gulls, not to mention the
darters and parrots.
As to the viscera, HUXLEY showed the close likeness be-
tween the various membranes which divide the coelom and the
corresponding membranes in the crocodile, and I endeavoured
to show that the ostrich is not in these particulars more.
reptilian than many other birds. The partial persistence
M
162
STRUCTURE AND CLASSIFICATION OF BIRDS
of the left aortic arch is an approach to the reptile ; but birds
belonging to the most diverse orders have this arch left in
varying degrees of perfection; so that no stress can be laid
upon this anatomical fact as a mark of low position. It has
been pointed out that the Struthiones are unlike other birds
in the absence of a syrinx; and in the absence of this
specially bird organ they approach so far to the lower
forms. This is not, in the first place, true of all the Struthiones,
for Rhea has, as has been pointed out, a syrinx fully as typical
as that of most birds, while the American vultures and even
the storks have nothing in the way of a specialised syrinx.
In fact, without going into further detail, it seems impossible
to select any existing group of bird which is distinctly more
reptilian than any other.
Since positive characters appear to fail us in discriminat-
ing between the relative positions of the several groups of
birds, it seems to be not unreasonable to turn for light to
negative characters. Birds as birds have many peculiarities
of organisation, which are impossible in other animals; for
example, patagial muscles cannot exist without a patagium
to contain them. It may therefore be permissible to draw
with caution some inferences from the absence or simplicity
of certain peculiarly ornithic structures which, it appears
obvious, must have originated within the class. The lower
types will surely possess fewer of these essentially ornithic
organs or modified organs.
There is a general belief in the modified character of all
the birds which GARROD placed in his subclass Anomalogonatæ.
Nevertheless there is something to be said in favour of their
primitive nature. Without absolutely urging the acceptance
of this view, it may be useful to refer briefly to certain
reasons which might be alleged in support of such a placing
of the Pico-Passeres. Their small to moderate size is to
some extent an argument. The most ancient mammalia
and reptiles are small as compared with some of their later
and more modified representatives. Universal distribution
is another argument, as is possibly chiefly arboreal life. In
anatomical structure we find that many essentially ornithic
THE CLASSIFICATION OF BIRDS
163
ATS
11
characters have not yet put in an appearance, or have done
so only to a small extent. There is no member of the
group, wide though it is, in which there is an ambiens, a
special bird muscle. It may be that GADOW's discovery of
a small independent slip of the rectus femoris, which he
interprets as a rudimentary ambiens, is really the beginning
of this characteristic muscle. The remarkable peculiarities
of this muscle seem to forbid the notion that it is the direct
descendant of anything reptilian. And we have the un-
doubted fact that, apart from the possible rudiment already
referred to, it is present in no pico-passerine bird. If it
had disappeared in them there would be here and there a
rudiment left. But nothing of the kind has been hinted by
GARROD and FORBES, who between them dissected so many
of these birds, and who would have been especially on the
look-out for such a point. I should therefore be disposed
to disagree at once with GARROD's opinion that those birds
which have lost the ambiens 'may be set down as having
possessed the muscle in their ancestral form.' The ambiens
is so purely a bird muscle, though it may doubtless have its
homologue among reptiles, that one cannot but think that it
was acquired within the class; and the facts discovered by
MITCHELL (see above) entirely support this way of look-
ing at the matter, and indeed suggested it. As to the
muscular system of the wing, a highly characteristic muscle
is the .expansor secundariorum ; this was supposed for
some time to be absent in the group under consideration,
but it has been found to occur in some of them. In the
majority of those in which it does occur its structure is
decidedly more rudimentary than in some of the Homalogo-
natæ. It is true that FÜRBRINGER regards this muscle as
the abortive remnant of a reptilian muscle. But this state-
ment cannot be made about the patagial muscles, which are
essentially ornithic..
Now it is noteworthy that, with the exception of the
colies, not a single bird referable to the great group of Ano-
malogonatæ has a biceps slip, while in the majority of them
the tendon of the tensor brevis is exceedingly simple, being
LCUVU
1 2
164
OF BIRDS
TO
STRUCTURE AND CLASSIFICATION without the numerous subdivisions so often observable in
the same muscle in the (hypothetically) higher birds. Nor
is there the patagial fan, the junction between the tendons
of the longus and the brevis, a character, again, so frequent
among the larger birds. The complications in this case
seem to be much more likely an effect of specialisation than
that the simple conditions observable in the picarian and
other allied birds should be due to a process of degenera-
tion.
The simplicity and relative shortness of the gut is a
matter which is perhaps of importance in this connection.
The average relative length of the gut is much less on the
whole in the Pico-Passerines than in any other group. There
are, of course, some startling exceptions, but the general
statement holds. As to the cæca, it must be confessed that
they are as a rule small or absent. But the Coraciidæ and
the Todidæ are exceptions. The fact that both lobes of the
liver are frequently in this group of birds enclosed in separate
compartments, separated from the subomental space, seems
to me to be a vestige of a condition such as that which is
found in the crocodile. On the other hand certain of the
organs of the body show great variety and specialisation ;
particularly is this the case with the syrinx ; but to find
most of the organs of the body in a primitive condition,
while others are greatly specialised, is precisely what is so
often found in what are believed to be archaic types.
There can be no doubt that the Archeopteryx, far
though it may have diverged from the ancestral stock, has
retained more of the reptile than any other form known to
us. One or two of the characters are shared by that large
assemblage of birds which has been termed the Ano-
malogonatæ.
In the first place the structure of the foot of the Archæo-
teryx is that found in passerine birds. That the primitive
bird was arboreal seems likely, and it is not surprising to
find that this mode of life has led to various specialisations
in the foot, such as we find in the hornbills, &c. The
THE CLASSIFICATION OF BIRDS
165
Archæopteryx has the smallest number of cervical vertebræ
of any bird (ten), a fact which recalls the nine vertebræ or so
of the cervical region of lizards and crocodiles. Now, among
other recent birds there are none which have a smaller
number than that possessed by certain passerines. Fifteen
is perhaps the average number of these vertebræ among
birds; but among passerines the low number of thirteen is
to be met with. Nearly all the Anomalogonatæ are holorhinal,
as was the Archæopteryx. It is doubtful, however, whether
this particular fact advances my argument, as there are
reasons (see p. 144) for considering the schizorhinal arrange-
ment to be the older, and for looking upon the holorhinal as
a derivative.
There remains for consideration the large assemblage of
birds which, taken together, correspond to the Homalogonatæ
of GARROD. In a preliminary way we may regard, as I
have pointed out above, four characters at any rate as
primitive.
These are the presence of basipterygoid processes, the
possession of two carotid arteries and of the fifth cubital
remex, and the simplicity of the intestinal coils. The only
birds which have all of these are certain Galli and certain
Turnices. Allowing for the degeneration of the wing, the
struthious birds may be referred to a nearly equally low
place in the system. In many groups, however, we find a
near approximation to this presumably primitive condition.
Thus among the anserine birds Palamedea is deficient only
in the fifth remex. Among 'Grallæ’ it is only the saine
character that is wanting in certain forms to complete the
four requisite characters. And some of them—e.g. Cariama,
Psophiamhave this elsewhere missing feather, though those
particular forms have not some of the other characters.
Opisthocomus, the cuckoos, and Musophagidæ are not far
off from the base of the series, while the trogons, if they
had both carotids, would be among the hypothetically)
lowest groups. The facts in question may be thus tabu-
lated :-
166
STRUCTURE AND CLASSIFICATION OF BIRDS
-
--
-
-
---
-.
-.
..
.-
---
---
1
-
-----
'
Carotids
Basipt. Proc. i
Bifch Remex
Intestine
-
.
.
-
-
.
-
-
-
.
.
2 or 1
to ?
Colymbi.
Sphenisci.
Tubinares.
Steganopodes
Herodiones
QOQOT
11 + 1
+ or -
2 or 1
Complex
Complex
Complex
Complex
Simple (in
Platalea)
Complex
Simple
Complex
Complex
.----
.
+ till
-
-
-
..--.---.
2 or 1
2 or 1
-
-
-
-
Anseres i
Palamedece
Accipitres,
Tinami
Turnices.
Galli
Ralli
Grues .
Otides .
Linnicolae .
Pterocletes
Columbæ.
Alca
Opisthocomi
+ or -
i + (Podica)
+ (Psophic, &c.)
--
2 or 1
11 + + + + + + !!! + + + IIII + + +
Simple
Complex
Complex
Complex
Simple (some)
Complex
Complex
.
QOTG7QVQVOT OVCU O VOI TU QI Q7 Q7 Q7 Q7 Q7
..
--
or -
--
-
--
or 1
--
Complex
-
-
-
-
-
-
Cuculi
II + 1 + t of t 1 LI
.
-----
---
...
-
-...
-
2 or 1
2 or 1
Musophagi
Struthiones
Psittaci . .
Striges
Capriinulgi .!
Pico-Passeres.
...
----·
Complex
Simple
Complex
Simple
Simple
Simple (?)
I
2 or 1:
OP
to
+ or -
--------
I have italicised in the above list those groups which
come near to the supposed primitive condition; and it will
be observed that those groups which are italicised are enough
to account for the ancestry of the rest. The main difficulty
is perhaps presented by the Cuculi; but it may well be that
that group will ultimately prove to have a simple intestinal
tract. It will be observed also that the groups in question
comprise representatives of all the five large divisions of
existing birds admitted by GADOW, and of all the corre-
spondingly large divisions of FÜRBRINGER. Incidentally,
therefore, I find myself in reassuring agreement with those
authorities. In the systematic part of this work I have to
some extent discussed the mutual affinities of these different
groups.
ANOMALOGONATÆ
167
GROUP ORNITHURÆ
ANOMALOGONATÆ
Definition.—Generally quincubital. Ambiens and accessory femoro-
caudal always absent ; biceps slip rarely present. Cervical
vertebræ, 13-15. Atlas generally perforated by odontoid process.
Skull holorbinal.
This group of birds is equivalent to the similarly named
group of GARROD, with the sole addition of the Striges. The
total absence of the ambiens, even of all traces of that muscle
(see p. 95), is to my mind a sufficient reason for bracketing
together all these birds. I am of opinion that the ambiens
is not degenerate in them, but that it has not yet appeared.?
It must be admitted that there are not many other charac-
ters that run through the whole group. There are, never-
theless, certain peculiarities of structure that are confined or
nearly confined to this group. Thus, with the sole exception
of the parrots, a forked manubrium sterni is a peculiarity of
the Anomalogonatæ; so too, with the same exception, is the
presence of a cucullaris propatagialis. Again, it is only here
and in the parrots that the syrinx has so complicated a
musculature. The very prevalent shortness of the intestine
is a fact (not, it is true, without exceptions) not to be ignored
in considering the claims of this group to existence. The
feet are nearly always anisodactyle or zygodactyle, there
being but few other birds not referable to this group in which
that structure of foot is to be found; and those groups will
be treated of later as possible allies of the present. Powder-
down patches are exceedingly rare in this group, and but
few possess the expansor secundariorum.
I allow nineteen separate families of this group (whose
main characters are given in the table), of which some may
be united more closely than others.
I SEEBOUM, ' An Attempt to diagnose the Pico-Passerine Group of Birds,' &c.,
Ibis, 1890, p. 29.
? A case which appears to contradict this statement is dealt with on p. 163.
168
STRUCTURE AND CLASSIFICATION OF BIRDS
adm.-
--
--
-
--------
-
Basi-
Leg
! Filtli i
i Remex Muscles
After- Oil Gland
Flexor
Tendons
shaft
Cucullaris
p. sec. Patagialis
Cæca | Carotids! Skull | Vomer
pterygoid|
Processes
Geographical
Distribution
w
..
-
-
.
-
+,0
Nude
+
Rud.
+,r.
R
1
+
--
vh.
+
Vb
+
di o
N.
N.
Feathered
N.
F. n.
' F.
---------
.
I
ax
Passeres
Coraciidæ
Meropidæ
Todidæ .
Trogonidæ
Alcedinidæ
Bucerotidæ
Coliidæ .
Upupidæ
Picidæ,
+
+ + + + oo + ot
A ~ (Y) | 1, vii.
AⓇY v.
AⓇY
A ⓇY
viii.
Ах
A Y V, vb).
AxY v.
AxY vii.
| A ~ (Y)
V, vb.
----
oo
+
+
o f
-
Æg. + ! Universal
Desm. Narrow | Old World
Desm. Narrow 0 Old World
Desm. Rud. o West Indies
Sch. + 1 +, rud. America, Africa, Asia
Desm.
o Universal
Desm.
0, rud. Africa, Asia
Desm.
Africa
Desm.
Old World
| Saur. Double : 0 Universal, exc. Aus-
tralia, Madagas-
car, and Polynesia
Desm.
South America
( Æg.
Central and South
1 Desm.
America
+
-
.
.
: 10
. .. +
-
-
-
+
-
+ +
+
-.-....--------
Rhamphastidæ
| +,0
+
Ax(Y)
o
Hoy on G7 Ya wa aa a a a7 07
+
t
-
Capitonidæ
,
.
+
to
AXY
+
+
...
-
LAXY
+
Bucconidæ
Galbulidæ
a. +
.
a. CE
.
!
Desm. | Rud.
| Desm. Rud.
+
N.
AⓇ(Y)
+
---
-
-
-
-
-
Momotidæ
+
F. n.
AxY
+
0
Desm.
Stout
-
-
-
-
-
---
+
;
0
2,1
America, Africa, Asia
Central and South
America
Central and South
America
0
Universal
South America
+,0 | Universal
+ | Universal

Æg.
of
---
+
N.
+
0
Scha.
+
O
-
Cypselidæ
Trochilidæ
Caprimulgidæ
| Strigidæ ,
+
A
Α
(A) * Y
! A
S
.
.
N. 0
.
Desma.
+
+
.
1 Scha
..
+,0
+,0
O
0
-
N.
:
1 +
Desm. '
+

-
--
---
-
----

ANOMALOGONATÆ
169
In the above table I have used twelve characters. The
Picidæ, Rhamphastidæ, and Capitonidæ agree in ten of these,
and are undoubtedly nearly allied birds. The Bucconidæ are
unfortunately not well known, but of the nine characters
which are set forth in the table they agree in eight with one
or other of the three families just mentioned.
The Coraciidæ and Meropidæ agree pretty well in all the
characters except the exact arrangement of the deep flexor
tendons, the carotids being variable. There will be but little
violence done if these groups are associated. The Cypselidæ
and Trochilidæ clearly come near together, agreeing as they
do in nine of the selected characters.
The Caprimulgidæ on the one hand, and the owls on the
other, each form a distinct group with no such near affinities
to any of the others as those which we have been considering.
The trogons are the only other group with basipterygoid
processes; they do not, however, come very near to the
Caprimulgidæ or to the owls; out of the selected twelve
characters they have at least four in which they totally
differ from the first, and five in which they differ from the
second. This group may be left as equivalent to the other
compound groups already considered.
The Todidæ are placed by GADOW close to the motmots ;
by FORBES, on the other hand, they are widely separated.
They agree with them in ten out of the twelve, showing
thus, it appears to me, a considerable nearness. They agree
equally closely with the Meropidæ on the one hand and the
Galbulidæ on the other. These four groups appear to me to
be worthy of association into one larger group.
We have left the Bucerotidæ, Upupidæ, Alcedinidæ, and
Coliidæ. The kingfishers undoubtedly come near to all of
these, in only at most four of the characters differing from
any one of them ; but they are as near to the motmots and
Rhamphastidæ. They should form a group apart.
The same may be said of the colies ; they are very near
to the hornbills and kingfishers, but equally near to the mot-
mots and Rhamphastidæ ; we may therefore place them in a
group apart. On the other hand the Bucerotidæ come nearer
170
STRUCTURE AND CLASSIFICATION OF BIRDS
to the Upupidæ than to any other groups except the colies
and Alcedinidæ; we may therefore unite them.
Finally as to the passerines. It is not possible to place
them very definitely nearer to one than to another of the
groups enumerated. They differ at the lowest in four
characters from any. They are, perhaps, furthest away from
the Bucerotidæ ; the two groups, in fact, are typical members
each of them of the piciform and passeriform birds of
GARROD. Their leanings are perhaps to the Cypselidæ and
to the Pici.
These conclusions may be tabulated as follows:-
Group A.--Aftershaft present; fifth remex always present,
Muscle formula, AXY. Expansor secundariorum present.
Desmognathous. Vomer present.
This group contains the families Coraciida, Meropidæ,
Todidæ, Galbulidæ, and Momotidæ.
: By both GADOW and FÜRBRINGER the Galbulidæ are
placed nearer to the Bucconidæ, and by inference to the Pici
(Picidæ, Rhamphastidæ, and Capitonidae). They differ, how-
ever, from these by the presence of the expansor secundario-
rum, which is so rarely present among anomalogonatous
birds that when present it seems to be of special importance.
The most salient point of agreement between these latter
birds is the form of the deep flexor tendons. But the
Bucconidæ are so little known that they may be found to
differ more than is at present suspected from the Pici. In
this case it may be desirable to separate both Galbulidæ and
Bucconidæ from the group with which I now associate them
and place them nearer together. Of the group as at present
constituted the Todidæ have perhaps the most claims to be
regarded as the most primitive forms. They have a feathered
oil gland and long cæca, which two characters do not coincide
in any other of the families now under consideration.
The next group, that of the Pici, may be thus defined :-
Group B.–Fifth remex always present; deep flexor
tendon of type VI. Expansor secundariorum absent.
Cucullaris propatagialis present. No cæca. Vomer
present.
ANOMALOGONATÆ
171
There are other peculiarities that unite these birds, which
will be found mentioned on p. 183.
The third group, containing the hornbills and hoopoos,
may be thus defined :-
Group C.-Oil gland feathered; fifth remex present.
Muscle formula, AXY. No expansor secundariorum. Cæca
absent. Skull desmognathous.
The colies are the only birds among the Anomalogonatæ
besides the Caprimulgidæ which possess the biceps slip; there
is a rudiment of this structure in BucorvuS.
The remaining families are treated of separately and need
not be defined here.
This arrangement, nearly coincident with that of GADOW,
is widely different from that of GARROD and FORBES. The
former divided the birds (excl. Striges) into the three groups
of Piciformes, Passeriformes, and Cypseliformes. They were
thus defined :-
Piciformes.-Oil gland tufted; cæca absent; external
branch of pectoral tract given off at commencement of breast.
Muscle formula, (A)XY. Picidæ, Capitonidæ, Upupidæ,
Bucerotidæ, Coliidæ, Alcedinidæ, Momotidæ.
Passeriformes.--Oil gland nude; cæca present; pectoral
tract simple or with external branch given off beyond middle
of breast. Muscle formula, AX(Y). Passeres, Bucconidæ (?),
Galbulidæ, Coraciidæ, Meropidæ, Trogonidæ.
Cypseliformes.—Oil gland nude ; cæca absent. Muscle
formula, A.
To these FORBES added a fourth group Todiformes, on
account of its having at once cæca and a tufted oil gland.
This latter group was regarded by him as most nearly repre-
senting the ancestral anomalogonatous bird.
172
STRUCTURE AND CLASSIFICATION OF BIRDS
PASSERES
Definition.—Oil gland nude. Skull ægithognathous. Atlas perforated
by odontoid process. One carotid, left. Cæca present, small.'
Muscle formula, AXY.” No biceps slip or expansor secunda-
riorum.
This is an enormous group of birds, numbering over
6,000 species, which are spread over the entire globe. As a
rule they are of small or moderate size; but some large
species, such as the raven and other Corvidæ, are included
in the assemblage. In spite of the numerous species and of
a certain amount of differentiation in external form, the group
is structurally a uniform one, the difference being in cha-
racters which have not as a rule been regarded as of primary
importance.
In all Passeres the foot has this structure: the first toe is
directed backwards, and none of the other toes are ever
changed in position. Cholornis is exceptional in that the
fourth toe is abortive.
GARROD noted, some years since, another peculiar character
of the group, which may possibly be universal, with the ex-
ception of Menura and Atrichia. This concerns the arrange-
ment of the tendon of the patagialis brevis; and the passerine
disposition may be understood from a comparison of the two
descriptions. In the passerine the tendon of the muscle
does not end upon the tendon of the extensor, as it does
in the picarian bird, but, though attached to it firmly,
it to the extensor condyle of the radius. This difference,
though small, appears to be constant to the Passeres. Another
character dealt with on p. 41 of the present work may be
also an exclusively passerine character. In birds belonging
to the present family the oblique septa, instead of having a
separate attachment to the sternum, are either not attached
In a specimen of Gracula internedia the cæca were as long as half an
inch, an exceptional length.
? Very rarely AX-.
PASSERES
173
at all, lying loosely over the liver, or have but one attach-
ment, which they share with the falciform ligainent.
It is very general-but there are a few exceptions, which
will be dealt with later--for the sternum. to have a forked
manubrium in front and a single pair of notches behind..
The number of rectrices present among passerine birds
varies. They are, indeed, completely absent in wrens of the
genus Pnoepyga. Twelve is the usual number, but ten only
occur in Xenicus, Phrenotrix, and Edolius, while Menura
superba has sixteen. The aftershaft is very weak and downy'
when present, and is sometimes (e.g. Paradisea rubra) absent
altogether. As to the pterylosis, we may take Ampelis
cedrorum, recently described by SHUFELDT,' as an example
of passerine pterylosis, mentioning afterwards such varia-
tions from this type as are met with. In the bird in question
the dorsal tract is exceedingly narrow from the origin in the
fairly continuous feathering of the head down to a point in
the pelvic region, where it is greatly dilated to form a
diamond-shaped area; this again contracts to the original
dimensions, and the tract concludes a little way in front of
the base of the oil gland. From the lateral angles of the
diamond-shaped area a tract runs to the feathering of the
legs. On either side of the oil gland arises a short tract,
which does not leave the trunk, but appears to be the hinder
part of the femoral tract of some other birds. It is perhaps
noteworthy that it is very similar to the corresponding one
of the Bucconidæ and Capitonidæ, also, however, of the
kingfishers.
The ventral tract divides early on the neck, and on the
breast is increased in breadth, the outer rows of feathers
being much stronger than the inner set; the latter (not the
former) are continued down to the cloacal orifice, which
they completely surround by a narrowish band of feathers.
The humeral tracts, which are strong, are connected with
the head feathering by a special neck band as wide as the
dorsal tract. NITZSCH does not figure this connection or
that of the diamond-shaped dorsal area of feathers with the
" In a paper dealing with Macrochires in J. Linn. Soc. vol. xx.
CU
174
STRUCTURE AND CLASSIFICATION OF BIRDS
LI
femoral feathering; but apart from this the same type of
pterylosis occurs in many types, such as Motacilla, Certhia,
Oriolus, &c. The principal variation is offered by those
passerines in which the spinal widened area is not solid, but
encloses a space.
We find this in Coracina cephaloptera and Seleucides.
In others (e.g. Eurylæmus) there is the same ephippial space
within the dorsal tract, but the posterior sides of the diamond-
shaped space are formed by a single row of feathers, which
contrast with the mass of feathers which form the antero-
lateral boundaries of the space. This arrangement culmi-
nates in, for example, Hirundo and Diphyllodes, where the
dorsal tract forks, and there is no connection between the
ends of the fork and the single posterior part of the spinal
tract.
: The skull of Passeres has been mainly investigated by
PARKER and by SHUFELDT.2 Corvus may be taken as a
type, and the divergences therefrom noted later. As are all
passerines, it is ægithognathous; the maxillo-palatines extend
obliquely outwards and backwards; they approach each
other in the middle line, and expand over the vomer. The
vomer is broad and bifurcate both anteriorly and posteriorly;
from the anterior horns a small separate piece of bone goes
1
ULU
For passerine pterylosis, see, in addition to NITZSCH, GIEBEL, 'On Ptery-
losis of Paradisea,' Zeitschr. f. d. ges. Naturw. xlix. p. 143, and for Philepitta
ibid. p. 490 ; SHUFELDT has described Chamcea, Journ. Morph. iii. 1889, p.
475; HELLMANN, ' Beitrag zur Ptilographie u. Anatomie der Hirundo rustica,'
J. f. O. iv. 1856, p. 360; GADOW, 'Remarks on the Structure of Certain Hawaian
Birds,' in WILSON and Evans's Aves Hawaienses, ii. Sept. 1891.
? For osteology of Passeres see PARKER, 'On the Structure and Development
of the Crow's Skull,' Month. Micr. Journi. 1872, p. 217; 'On the Development
of the Skull in the Tit and Sparrow Hawk,' ibid. 1873, pp. 6, 45; . On the
Development of the Skull in the Genus Turdus,' ibid. 1873, p. 102 ; 'On
Ægithognathous Birds, Trans. Zool. Soc. ix. p. 289, x. p. 251; MURIE, On
the Skeleton and Lineage of Fregilupus,' P. Z. S. 1874, p. 474. Lucas,
· Notes on the Osteology of the Thrushes,' &c., P. U. S. Nat. Mus. xi. 1888, p.
173.
SHUFELDT, “Osteology of Eremophila,' Bull. U. S. Geol. Surv. vi. p. 119;
• Osteology of Lanius,' ibid. p. 351; On the Skeleton in the Genus Stur
nella,' &c., J. Anat. Phys. xxii. p. 309; Osteology of Habia Aule,' v. p. 438;
· Osteological Notes on Puffins and Ravens,' ibid. p. 328; GIEBEL, · Zur Osteo-
logie d. Gattung Ocypterus,' Zeitschr. f. d. ges. Naturw. xxi. p. 140.
PASSERES
175
1
on each side to the maxillo-palatines. These are the septo-
maxillaries of PARKER, and appear to remain perfectly dis-
tinct in Corvus cornix, but not in Corvus frugilegus. There
are no basipterygoid processes; the pterygoids have a long
foot-like attachment (as long as the free part of the bone)
not only to the palatines, but to the interorbital septum also.
The nares are holorhinal and pervious. In Corvus cornix
the lacrymals reach the jugal bar; there is practically no
orbital portion, the descending limb being closely attached
to, but not fused with, the broad and thick ectethmoid. The
mandibular rami have a large oval perforation near to the
articular surface.
Among genera nearly related to the Corvidæ are various
slight modifications of skull structure. In Manucodia, for
instance, the rostrum is broadly ossified and fused with the
co-ossified palatal plates of the maxillæ. The nasal septum
is complete, and the conjoined ectethmoids and lacrymals
are enormously swollen. In Ptilonorhynchus violaceus the
ectethmoids and lacrymals are separate, though in contact;
contrary to what is found in Corvus, it is the latter and not
the former which border the orbit above. The palatal con-
ditions of Manucodia are repeated and emphasised in Gym-
norhina and Strepera. There is a firm union across the
middle line in front of the vomer, with which, indeed, the
anterior horns of the vomer are ossified in Strepera. In both
birds, moreover, the pterygoids are fused with the pala-
tines, and the nostrils are partly obliterated by bony growth.
The 'desmognathism'thus produced in the crows of
Notogæa’ is not limited to that family. In Pheucticus
and in Cracticus cassicus there is the same state of affairs.
Other features in which the passerine skull shows variations
are the maxillo-palatines, vomer, and pterygoids ; in Gracula
javanensis, for example, the pterygoid has a very limited area
of articulation with the palatine ; there is no expanded foot,
as in crows, &c.; the maxillo-palatines are very long and
slender, actually reaching the inner plate of the palatines.
The vomer is narrow in the body, though the two anterior
cornua' are thick. Trochalopteron is almost desmognathous
176
STRUCTURE AND .CLASSIFICATION OF BIRDS
1
in the sense of HUXLEY; the two maxillo-palatines, dilated
at their ends, come absolutely into contact under the vomer,
the middle part of which they completely cover. In Guis-
calus versicolor the same arrangement occurs, the maxillo-
palatines being extraordinarily slender before they dilate to
overlap each other and to cover the vomer.
As to the rest of the skeleton, Corvultur albicollis may
serve as a type. There are fourteen cervical vertebræ ; un-
impaired hypapophyses extend from the tenth to the first
dorsal. Five ribs reach the sternum, to the keel of which
the furcula is joined.
The most salient variations from this plan are shown by
many genera in which the furcula does not join the keel of
the sternum, by Corcorax, in which six ribs articulate with
the sternum, and above all by Gymnorhina, where there is
a catapophysial canal, beginning with the seventh and
ending with the tenth vertebra. In this and other forms
the hypapophyses of the last cervical and the first dorsal
vertebræ are reinforced by strong lateral catapophyses.
In the table on the opposite page are some intestinal
measurements in inches. The most noteworthy fact in the
anatomy of the alimentary tract is the absence of the gizzard
in certain tanagers.
In almost all Passeres 2 the flexor hallucis is absolutely
independent of the flexor communis, there being no vinculum
at all.
These characters are-adding to them those used in the
diagnosis of the family—the only ones that are universal, or
nearly so, among the Passeres. There are, however, a number
of anatomical features in which the passerines show differ-
cnces among themselves. The most abnormal Passeres on
JUCU
I Cf. FORBES, 'On the Structure of the Stomach in certain Genera of
Tanagers, P. Z. S. 1880, p. 143, who quotes Lund's earlier (1829) paper on the
same matter.
? For myology of passerines see, in addition to GARROD, KLEMM, “ Zur
Muskulatur der Raben,' Zeitschi. f. d. ges. Naturw. xxiii. p. 107; SHUFELDT,
The Anatomy of the Raven, London, 1890; C. L. NITZSCH, ' Ueber die Familie
d. Passerinen,' Zeitschr. f. d. ges. Nat. xix. p. 389; C. B. ULRICH, “Zur
Characteristik d. Muskulatur d. Passerinen,' ibid. xlv. p. 28.
PASSERES
177
-
-
.
.
-..
-.-
S. I.
L. I.
Cæca
-
-
-
-
+
-
-
-
-
-
...
-
-
-
-
-
+
--
-
-
1
-
-
-
9
circo eres i
15 .
5.1
102
13.75
14.85
14.15
16.2
1.3
hi cô có c - t t 1 = =
E
12
1.
13
.
.
1.2
13
25
a
On
Myiophoneus Horsfieldi
Geocichla citrina .
Nesocichla eremita ...
Rimator malacoptilus.
Cracticus cassicus ..
Pastor roseus . .
Seleucides nigra. .
Manucodia atra . .
Uranornis rubra . .
Entomyza cyanotis .
Garrulax albogularis.
Cyanocorax cyanopogon
Cissopis leveriana .
Struthidea cinerea .
Hirundo rustica . .
Anthornis melanura .
Strepera graculina
Barita destructor. ..
Tanagra sayaca . .
festiva .
Ptilonorhynchus holosericeus
Gracula javanensis ".
Gymnorhina leuconota
Corvus corone . .
Ampelis garrulus . . .
10
I
-
2
-
1
•75
-
.6
6.25
6.25
·
.75
20
5
13
.15
•12
•75
.25
8
6.5
10.25
10.5
23
22
29.75
1.25
1.5
•5 (F.)
•25
or car
ܗܶ ܟܬ ]
the whole are the broad-bills Eurylæmidæ and the Australian
Menura and Atrichia, which form a sub-family, Menuridæ.
There are differences of opinion as to which of these is most.
independent of the normal Passeres. FÜRBRINGER separates
the Menuridæ, GARROD and FORBES 1 the Eurylamidæ. We
should explain that in first of all discussing this particular
point we are not proceeding in historical sequence. It was.
the syrinx that first of all attracted the attention of JOHANNES
MÜLLER, whose divisions of the Passeres were the earliest to:
be based upon anatomical structure ; and in the sequel we.
shall show that his divisions are in the main correct, even
allowing for our greatly extended knowledge. It is, however,
in our opinion, beyond cavil that the major subdivisions of
1 GARROD's contributions to our knowledge of passerine birds are as.
follows : "On some Anatomical Peculiarities which bear upon the Major
Divisions of the Passerine Birds,' i. P. Z. S. 1876, p. 506; Notes on the
Anatomy of Passerine Birds,'ii. P. 2. S. 1877, p. 447; iii. ibid. p. 523; iv.
ibid. 1878, p. 143. The following papers are due to FORBES : 'Contributions.
to the Anatomy of Passerine Birds,' i.-vi. P.Z. S. 1880-2.
N
178
STRUCTURE AND CLASSIFICATION OF BIRDS
the group first concern one of the two views that we have
referred to above. The reasons which lead us to agree with
GARROD and FORBES’s separation of a group Desmodactyli,
as opposed to the remaining Passeres, which are to be so-
called Eleutherodactyli, are as follows: The Menuridæ
(Pseudoscines of SCLATER and FÜRBRINGER) are clearly in
some respects degenerate forms. The clavicle has become
rudimentary, and the muscles of the syrinx, while approach-
ing the typical oscinine form, where these muscles are
numerous and strong, have become to some degree weakened
by loss.
On the other hand the Eurylæmidæ, while they have
retained the typical mesomyodian syrinx-typical, because it

.

2
.
1
V
SS
.
.
..
S
.
.
...
.
.
W
-
.
.
.
COV
TE
FIG. 85.--SYRINX OF Eurylæmus.
FRONT VIEW. (AFTER FORBES.)
FIG. 86.-SYRINX OF Cymbi-
rhynchus. SIDE VIEW. (AFTER
FORBES.)
is distinctive of the vast majority of birds-have retained the
plantar vinculum,” which in other passerines has been lost;
they have also a simple manubrium sterni, this appendage
being forked in other passerines. In the feet too the third
and fourth toes are largely bound together, giving to the
group the name of desmodactyli.
The family Eurylamidæ ? contains the genera Eurylæmus,
Calyptomena, Serilopha, Psarisomus, Corydon, and Cyınbi-
rhynchus, all Old-World. They have no aftershaft, and the
oil gland is, of course, nude. There are twelve rectrices in
Occasionally absent in Calyptomena viridis.
? FORBES, 'On the Syrinx and other Points in the Anatomy of the Eurylä-
midæ,' P. Z. S. 1880, p. 380.
PASSERES
179
Cymbirhynchus. There is a wide ephippial space, elongated
and oval in form; the narrower parts of the tract behind
are two feathers wide.
The tongue (of Cymbirhynchus) is bifid at tip and
elongated and cordate.
The following are intestinal measurements of two species :
Cynubirliynchus
macrorhynchus
Eurylæmus
achromelus
05
Small int. . . 7.75 5.75
Large int. . .. 1.25
-75
Cæca
. . .1
Left liver lobe is the smallest.
The following scheme gives the classification of the
Passeres according to GARROD and FORBES :-

New World
Old World
Eurylæmidæ
I. DESMODACTYLI
II. ELEUTHERODACTYLI
A. Mesomyodi
a. Heteromeri
Pipridæ
Cotingida
b. Homoeomeri
Haploophonæ
Tyrannidae
(Rupicola)
Pittidæ
Philepittide
Xenicidæ
Tracheophone
Dendrocolaptidæ
Furnariidæ
Pteroptochidæ
B. Acromyodi
Abnormales.
Atrichiidae
Menuridae
Norrales
(= Oscines)
.-.-
-
.
-
Of the remaining Passeres the Mesomyodi (also sometimes
called Oligomyodi) are divided into two subdivisions, according
as to whether the chief artery of the leg is the femoral or
sciatic. In the Heteromeri (with the exception of Rupicola)
it is the femoral, in the others (Homæomeri) the sciatic. All the
Mesomyodi have but one pair of muscles upon the syrinx or
none at all. But the name of Mesomyodi is derived from the
fact that these intrinsic muscles are attached to the middle
of the bronchial semi-ring which bears them. The Haploo-
phonæ are those mesomyodians in which the syrinx is quite
N 2
180
STRUCTURE AND CLASSIFICATION OF BIRDS
of the normal fashion ; the Trachephonæ are those in which
the last rings of the trachea are much modified, and the
syrinx may be termed tracheal.
The Mesomyodi with a tracheobronchial syrinx comprise
representatives from both the Old and the New Worlds. In
them the syrinx presents a varied form, coupled with the fun-
damental resemblance indicated. JOHANNES MÜLLER has
figured and described a number of genera. GARROD has
figured and described others. ' In Lipaugus cineraceus (of
the family Cotingidæ) the intrinsic muscle is of great width,
which seems to foreshadow its division in the Oscines into a
complex of muscles; it is attached to the third bronchial
semi-ring.
The first and second bronchial semi-rings resemble the
tracheal in their flatness, depth, and close approximation.
Those which follow are slightly ossified throughout. In
Heteropelma and Chiromacheris, which are Pipridæ, the
syrinx is very similar. In Pipra leucocilla the intrinsic
muscle has a tendency to split into two, a further approxima-
tion to the Oscines. In Hadrostomus aglaia, a cotingid, the
wide and thin intrinsic muscle is attached to the first bron-
chial semi-ring. This semi-ring is close to the last tracheal
ring, and is like it in structure, being deep. The next
bronchial semi-ring is separated by a considerable interval,
and the third by a wider interval still, from the ring in
front.
In the Madagascar Philepitta, which FORBES I was the
first to refer definitely to the present group of passerines, the
structure in some respects recalls that of the Eurylæmidæ.
The manubrium sterni is but slightly bifid; but it has in
the normal passerines no vinculum. The syrinx, on the
other hand, differs from the Old-World Mesomyodi by the
details of its structure (see figs. 87, 88). The different arching
of the bronchial semi-rings leaves great membranous spaces
in the wall of the syrinx. The first two semi-rings are very
concave upwards ; the two following are not so markedly
concave; the next is concave in the reverse direction. The
L'On some points in the Structure of Philepitta,' &c., P. 2 S. 1880, p. 387,
PASSERES
181
intrinsic muscles are wide and thin, nearly in contact with
each other before, and behind they are attached to the first
semi-rings everywhère but at their tips. Pitta has a much
simpler syrinx, approximating so far to that of the Eurylæ-
mida ; the muscles are thin and accurately median in inser-
tion. Pitta is unique among passerine birds by reason of
the deep temporal fossæ of the skull, which nearly meet


1
.
.
.
X
.
.
S
A
:
W
.
.
ry
DO
i.
U:
FIG. 87.--SYRINX OF Philepitta.
SIDE VIEW. (AFTER FORBES.)
FIG. 88.--SYRINX or Philepitta.
FRONT VIEW. (AFTER FORBES.)
behind, in a way that is seen in some other birds not
passerine.
In the New Zealand Xenicus and Acanthisitta? there are
В


ST
.
re
a
Sa
.
LIV
2
/
<
WIN!
4
AO
Fig. 89.-SYRINX OF Xenicus. A. FRONT VIEW. B. BACK VIEW.
(AFTER FORBES.)
only ten rectrices, twelve being the number characteristic of
the majority of the Passeres. The syrinx of Xenicus as seen
in the annexed figure is quite typically mesomyodian. The
last few tracheal rings are consolidated into a large box, to
the top of which the intrinsic muscles (small and median in
insertion) are attached.
? FORBES, ' On Xenicus and Acanthasitta,' &c., P. 2. S. 1882, p. 569.
182
STRUCTURE AND CLASSIFICATION OF BIRDS
O
We now come to the Tracheophonæ, which are exclu-
sively American in range. Their distinguishing mark is, of,
course, the tracheal syrinx, whose general structure has
been already explained (see p. 67). Besides these general
agreements the Tracheophonæ show variations in structure.
Heterocnemis, for instance, is unique among them and
the Mesomyodi in general by the existence of a bilaminate
tarsus, as in the Oscines. Conopophaga and a few others 1
have a four-notched sternum, while Furnarius, Synal-
laxis, and a few others have, as has no other passerine,
a schizorhinal skull. Again, the maxillo-palatine of the
Dendrocolaptidæ, Furnariidæ, and Pteroptochidæ are like
those of oscinine Passeres in being slender and curved back-
wards, instead of being comparatively wide and blunt, as in
other Mesomyodi. Phytotoma is unique among passerine
birds for the nasal gland groove on the frontal bones, as in so
many water birds.?
The remaining group of Passeres, the Acromyodi, are
sometimes called Oscines and sometimes Polymyodi, the latter
term having reference to the numerous intrinsic muscles of
the syrinx. It was discovered by KEYSERLING and BLASIUS
that, with the exception of the Alaudidæ, the Oscines have a
bilaminate tarsus, the hinder surface being covered by two
closely apposed scutes. It sometimes happens in the forms
which are on that account spoken of as 'booted') that the
anterior face of the tarsus is covered by a single scute. The
syrinx of these birds is complex in the multitude of its
muscles, of which there are four or five pairs. The only
exception to the muscle formula AXY- exists in this group;
in Dicrurus there is the reduced formula of AX --. Ocypterus,
the only passerine with powder down, is referable here.
Referable to this group, but separated from the more normal
members as · Abnormales' by GARROD, are the two genera
Atrichia and Menura, which are also regarded as the types
of separate families. These two anomalous birds are by
| FORBES, 'On some points in the Anatomy of the Genus Conopophaga,' &c.,
P. Z. S. 1881, p. 485.
2. PARKER, Ægithognathus Birds, ii. p. 258.
PASSERES
183
some systematists placed in a group Pseudoscines, equivalent
to the remaining Passeres.
The anatomy of the two genera has been mainly investi-
gated by GARROD, who studied principally the syrinx. They
are purely Australian in range. According to FÜRBRINGER
this group of passerines is in many respects intermediate
between the other passerines and the Pici. With the latter
group Menura probably and Atrichia certainly agree in the
following myological points: the origin of the rhomboideus
profundus from the pelvis ; in the tendon of insertion of the
supra-coracoideus upon the shoulder joint; in the origin of
the latissimus dorso-cutaneus from the ilium and its covering
by the leg musculature. GARROD also called attention to
the fact that the patagialis brevis was picine and not passerine.
The syrinx of Menura! has three pairs of intrinsic mus-
cles, which are inserted respectively into the last tracheal
ring and on to the second and third bronchial semi-rings.
There are three modified bronchial semi-rings. So too in
Atrichia, where, however, there are but two pairs of syringeal
muscles, as shown in the figure.
The clavicles are rudimentary in Atrichia; there is no
hypocleidium in Menura, another picine character. Menura
has, furthermore, a chain of three supra-orbital bones.
PICI
Definition.-Feet zygodactyle; aftershaft small or rudimentary ;
oil gland tufted. Muscle formula of leg, AXY (AX); Gall
bladder elongated. Skull without basipterygoid processes.
The woodpeckers, which form the first family of the
assemblage, Picidæ, are a well-marked group of birds, contain-
ing about three hundred and fifty species, as allowed by the
late Mr. HARGITT.3 They inhabit most parts of the world,
excluding only Madagascar, Australia, and Polynesia.
For passerine syrinx see Joh. MÜLLER IN Abh. Berlin. Akad., 1845 ; HERRE,
Dissertatio de Aviur. Passerinarum Larynge Bronchiali, Gryphiæ, 1859; and
GARROD and FORBES in papers already quoted.
? W. MARSHALL, Die Spechte. Leipzig, 1889.
s Brit. Mus. Catalogue, vol. xviii.
184
STRUCTURE AND CLASSIFICATION OF BIRDS
una
Twelve rectrices is the rule for this family, but the outer
ones are sometimes feeble, and I found only ten in Tiga
Shorei. The aftershaft is present. The pterylosis varies
somewhat. But NITZSCH has pointed out that this peculiarity
... which occurs almost universally among them, is the
presence of a small inner humeral tract running along upon
the most elevated points of the shoulder parallel to the
very broad main tract.' That this second humeral tract also
occurs among parrots may be a matter worthy of considera-
tion. It appears, at any rate, to distinguish the woodpeckers
from other picarian birds.
In Picus viridis the narrow dorsal tract passes down the
middle of the neck and ends abruptly at the end of the
scapulæ or a little before. Behind this are two oval wide
patches, which correspond to the foot of the Y in other
birds, which have a dorsal median apterion. There is a
break between these patches and the posterior end of the
dorsal tract, which runs to the base of the oil gland undivided.
On either side of this and of the oil gland is a fainter and
narrower tract. In Tiga Shorei there is no break between
the several regions of the dorsal tract; the anterior part
narrows and forks into two branches, consisting of but one
row of feathers, which immediately after dilate into the wide
interscapular tracts; from the lower angle of each of these
a single row of feathers joins the median posterior part of
tract. The diamond-shaped spinal apterion is thus com-
pletely enclosed within the dorsal tract.
Sphyrapicus nuchalis 1 has a solid spinal tract dilating
between the shoulders into a rhomboidal but still solid area,
as SHUFELDT says, like a passerine.
In Centurus striatus the arrangement is more like that
of Picus viridis, but slight scattered feathering unites the
middle and posterior portions of the dorsal tract. .
The ventral tracts of Picus divide early in the neck and
at the commencement of the pectoral region; each gives off a
stronger outer branch. In Tiga Shorei the separation between
these branches is not nearly so marked as is shown in
L'Observations on the Pterylosis of Certain Picidæ,' Auk, 1888, p. 212.
PICI
185
T
NITZSCH’s figure of Picus viridis. This woodpecker is so
far much more like a parrot.
In Jynx the interior part of the dorsal tract forms a
continuous Y, of which the fork is hardly wider than the
handle. This is completely discontinuous with the median
posterior portion of the tract.
The tensores patagii 1 are very simple. The tendon is
single. There is a conspicuous cucullaris patagialis, but
no biceps slip. Each tendon, both longus and brevis, is
reinforced by a tendon from the pectoralis. In Centurus
striatus the slip to the longus is muscular in origin; it
seems to be more usually tendinous. .
The deltoid is an extensive muscle.
The latissimus dorsi posterior appears to be totally absent,
as in Indicator.
As to the leg muscles, the accessory femoro-caudal is
always absent. The femoro-caudal and the semitendinosus
are always present; the accessory to the latter may or may
not be present, its occurrence in different genera being
shown in the following list :-
With an Accessory Semitendinosus
Without an Accessory Semitendinosus
Gecinus viridis
Picus major
Gecinus vittatus
Picus minor
Leuconerpes candidus
Picoides tridactylus
Melanerpes formicivorus Sphyrupicus varius
Chloronerpes yucatanensis
Mulleripicus fulvus
Hypoxanthus Rivolii
Jynx torquilla
Dryocopus martius
Picolaptes affinis
Tiga Shorei
Tiga javensis
Centurus striatus
Melanerpes erythrocepha-
lon
Colaptes mexicanoides
1 NITZSCH-GIIBEL, · Zur Anatomie der Spechte,' Zeitschr. I. d. ges. Naturu.
xxvii. (1866), p. 477.
186
STRUCTURE AND CLASSIFICATION OF BIRDS
CU
UUU.
VIA
The deep flexor tendons are like those of toucans and
barbets (cf. p. 101).
The tongue is elongated, and so are the ceratohyals in
relation to it, overlapping and grooving the skull. As a rule
among the woodpeckers the right lobe of the liver is larger
than the left; they are equal in Xypoxanthus Rivolii. The
gall bladder appears to be absent in Leuconerpes candidus
and in Xypoxanthus ; it is long and intestiniform (like that of
a toucan) in Gecinus viridis, Dryocopus martius, and Jynx.
The intestines are without cæca ; ? the following are some
measurements :- .
Chloronerpes yucatanensis . . . 8 inches
Picus minor . . . . . . 12 »
Xypoxanthus Rivolii . . . . 12 ,
Dryocopus martius . . . . 20 »
The syrinx has no remarkable characters. It is quite
typically tracheo-bronchial with a pair of extrinsic and
a pair of intrinsic muscles.
As to the skull, the woodpeckers have an unusual palatal
structure, which led PARKER 3 to invent the terin Sauro-
gnathous in order to express this peculiarity. The palate of
the woodpecker has, however, been variously interpreted.
Professor HUXLEY, in his paper on the bird's skull, directed
attention to an apparent vacuolation of the palatines, which
is illustrated in the accompanying figure (fig. 90); a slender
bar of bone passes backwards and comes into near relations
with an equally slender projection forwards of the palatine
bone, thus enclosing a space which in the fresh skull is filled
with membrane. The anterior process in the dried skull
is sometimes continuous (fig. 90), but sometimes not con-
tinuous with the ascending lamina of the palatine. Where
it is not continuous Professor HUXLEY found that its appa-
I J. LINDAHL, Some New Points in the Construction of the Tongue of Wood-
peckers,' Am. Nat. 1879, p. 43.
? Exceptionally present in Gecinus viridis.
3 "On the Morphology of the Skull in the Woodpeckers,' &c., Tr. Linn. Soc.
(2), i. 1875, p. 1. See also KESSLER, · Zur Naturgeschichte der Spechte,' Bull.
Soc. Nat. Mosc. 1844, p. 285.
PICI
187
IS
TA
AFOS
2
ia.
4
.
UN
RA
1
.
TA
OSOS
.
rent continuation was a separate bone, which he regarded
as the vomer—the vomers thus being paired.
A few years later a different complexion was given to the
subject by a paper written by Professor GARROD.He con-
firmed HUXLEY'S description of the supposed vomers, but
regarded them merely as the perfectly ossified edge of the
imperfectly ossified palatines. This opinion was chiefly
based upon the discovery of a small median bone lying
between the posterior ends of the palatines (, fig. 90), not
observed by HUXLEY. This bone, identified by GARROD.
with the vomer of other birds, occupies,
as he admits, a somewhat posterior posi-
tion, which is parallel, however, as he also
points out, at any rate in Megalæma.?
PARKER'S paper upon these birds is a
long and elaborate one, but contains no
reference to that of GARROD. The bone
discovered by GARROD is figured and de-
scribed as the medio-palatine, and is in-
variably figured as distinct from the
palatines, between which it lies. PARKER
adopts HUXLEY's identification of the
vomers, but finds that they are often
divisible each into several splints of bone;
Fig. 90.-SKULL OF
the connection with the palatines in front
WOODPECKER (Geci-
and a median series of bonelets (collectively nus viridis). Ven-
TRAL VIEW. (AFTER
termed by HUXLEY the ossified internasal
GARROD.)
septum) are spoken of as septo-maxil- PP, palatines ; Pt, ptery-
laries. It may be sometimes noticed—I
have observed it in Leuconerpes candidus—that the anterior
ends of the pterygoids, which in the Pici run for a consider-
able way over the outside of the palatines, come into actual
contact with the commencement of the vomers.3
Another peculiarity of the woodpecker's skull is the fre-
1.Note on some of the Cranial Peculiarities of the Woodpeckers,' Ibis,
1872, p. 357.
? See under • Capitonidæ,' p. 196.
3 SHUFELDT also (On the Question of Saurognathism of the Pici, &c.,
P. Z. S. 1891, p. 122) argues against HUXLEY'S view.

w
HAT
227
goids ; %, vomer.
1
CU
188
STRUCTURE AND CLASSIFICATION OF BIRDS
VEL
quently Y-shaped form of the pterygoids. An outer.
forwardly directed process is given off near to their articula-
tion with the quadrate. The extraordinary hyoid connected
with the long and exsertile tongue is, of course, a marked
feature of the group. The long distal piece of the bran-
chials curves over and furrows the cranium of those species
in which it exists.
In the wryneck (Jynx) the vomers are small, but
thoroughly picine. The pterygoids have, however, no
forwardly directed process, and do not extend quite so far
over the palatines.
There are fourteen cervical vertebræ. Hæmapophyses
do not extend behind the first dorsal. There is a complete
canal for the carotids formed in the cervical region by the
hæmapophyses. Four vertebræ enter into the formation of
this in Thriporax Feddeni. The sternum has two notches on
either side, and has the spina exterior only, which is bifid.
Four ribs reach it. The clavicles form a U-shaped furcula,
but are expanded above, as in the toucans and barbets.
The Bucconidæ is a South American family of zygodac-
tyle birds whose anatomy ? is at present but little known, and
whose affinities are therefore doubtful. It is only provi-
sionally that I place them in the present position.
Bucco maculatus has a nude oil gland and twelve rectrices.
The inferior feather tract starts from the symphysis, leaving
a bare space on either side; it divides at the angle of the
jaw, and thence the two halves remain separate. Each of
them gives off a stout outer pectoral branch. The dorsal
tract is in two quite separate parts, separated by a good
space; the posterior part is forked for half its length,
tapering anteriorly to a point.
· In Monasa panamensis each part of the posterior fork
"This character is nearly unique among anomalogonatous birds. I
deseribe it, however, above (p. 176) in Gymnorhina. The nearest possible ally
in which it occurs is a parrot.
? GIBBEL, “ Zur Osteologie der Gattung Moroasa, Zeitschr. f. d. ges. Naturio.
xviii. 1861, p. 121:.
PICI
189
is connected with the anterior part of the dorsal tract by a
single row of very small downy feathers.
In Malacoptila fusca' the oil gland has a few fine hairs
at the apex ' (NITZSCH). The aftershaft is absent.
The tongue of Bucco maculatus is long, flat, and thin ; the
tip is not lacerated; the base is spiny.
The muscle formula of the leg is given as AXY--. Two
carotids are stated to be present.
The deep flexor tendons are like those of the Capitonidæ.
The flexor hallucis supplies digits I., II., IV. The flexor
profundus supplies only digit III. The two where they
cross are connected by a small vinculum.
Monasa nigrifrons has fourteen cervical vertebra. The
atlas is perforated for the odontoid process. The eighth
vertebra has two catapophyses, which come into contact at
their bases in the middle line; on the ninth is the first
median hypapophysis ; these continue to the first dorsal ;
on the thirteenth cervical are large catapophyses, which are
present, but much smaller, on the hypapophysis of the next
vertebra. There are only three free dorsals, all of which
bear ribs reaching the deeply two-notched sternum, which
has a long spina externa.
The clavicles are expanded into a wide, thin, roughly
triangular plate at their attachment to coracoids; there is a
thin but broadish hypocleidium where they meet below.
The skull is desmognathous, and in front of the conjoined
maxillo-palatines is a gap of about half an inch in length
in the bony palate. The process of the squamosal very
nearly reaches the jugal bar. The lacrymal completely
reaches the jugal bar in front, and the descending process is
in contact, but not fused, with the strong and swollen
ectethmoids. The interorbital septum is quite complete, as
is the intranarial.
The Rhamphastidæ (toucans), with their large bills,
serrate slightly at the edge, bear a certain superficial resem-
blance to the hornbills, with which, however, they have no
specially intimate connection. They are, on the other hand,
190
STRUCTURE AND CLASSIFICATION OF BIRDS
undoubtedly nearly related to the Capitonidæ, and show
slighter but still recognisable points of affinity with the
Passeres. The toucans, which are purely tropical American,
consist, perhaps, of only one well-marked genus, Rhamphas-
tos, which, however, has been subdivided into Pteroglossus,
Aulacorhamphus, Selenidera, and some others. The toucans
have a tufted oil gland, an aftershaft, and ten rectrices.
The pterylosis (cf. NITZSCH) is characterised by the wide
lateral neck spaces.
The dorsal tract does not divide on the neck, nor is it as
a rule' continuous throughout. There is a break between the
straight anterior portion and the Y-shaped posterior portion.
The ventral tract divides in the middle of the neck, and
there is a strongly marked outer branch to the pectoral
tracts. The femoral tract does not, according to my own
experience, arise so early from the spinal tract as NITZSCH
figures.
• The intestinal tract of the toucans is short but volumi-
nous, eighteen inches in Rhamphastos dicolorus, nineteen
inches in R. carinatus. There are no cæca.
The proventriculus is zonary; the stomach is a weak
muscular bag.
In the liver the right lobe is larger than the left, three
times larger in R. carinatus.
The most characteristic feature in the anatomy of the
family concerns the gall bladder; this has been principally
investigated by FORBES. It will be seen that the gall bladder
is tubular, and of very great length (4.15 inches in a specimen
of Rhamphastos dicolorus), as also in the Capitonidæ and a
few Picidæ (99.v.) I found in Rh. tocard an exceptional state
of affairs. As in all (?) toucans, the gall bladder is long,
but from the upper extremity two separate cystic ducts arise,
which soon fuse to separate again ;3 they open, however. in
| Nitzsch mentions as an exception an unidentified species. And in
Selenidera and Aulacorhamphus I could find no break.
2 Note on the Gall Bladder, &c., of the Toucans and Barbets,' P. Z. S.
1982, p. 94.
3 This may perhaps be regarded as a faint indication of the rete found in
some reptiles..
PICI
191
common with each other and with the hepatic duct into the
intestine. There are two pancreatic ducts in this species,
and one of them is peculiar in having a distinct, though
short, diverticulum near to its intestinal orifice.
The tongue is long, horny, and feathered along the
margins.
The toucans as a rule possess only one carotid, the left.
But in an example of Rh. dicolorus FORBES found both
carotids present. The second is much smaller ; it is quite
pervious, however, and blends with the left at the entrance
to the neck.
The syrinx is in some respects peculiar. As in some
other picarian birds, the last three or four tracheal rings are
fused to form a bony box, which is marked by a deep furrow
mesially and behind. This region of the syrinx is much
compressed antero-posteriorly. The intrinsic muscles are
attached to the upper part of the box.
The first bronchial ring is ossified in front; posteriorly
each half is L-shaped and fibrocartilaginous. The descending
limbs of each L are in the same straight line as the trachea ;
they are closely applied to each other, but really separated
by a membrane of very short extent, the bronchidesmus.
They are in close contact with the inner end of the ossified
half of the ring. At the lower end of these cartilaginous
pieces is a separate rounded bit of cartilage, which is simi-
larly connected with the second ring.
The tensores patagii are very simple. The tendon of the
brevis is quite undivided. Each has a tendinous slip from
the pectoralis. There is a cucullaris patagialis.
The deltoid is particularly long in its insertion.
The anconcus has no humeral attachment. It arises
by fleshy fibres (not a Y-shaped tendon) from the scapula.
The gluteus maximus extends below the acetabulum ; there
is no glutaus externus.
The muscle formula of the leg is AXY-. The semitendi-
nosus is attached to the leg bone separately from the semi-
membranosus ; it has also a tendinous insertion on to gastro-
cnemius. The deep plantar tendons are as in Megalama.
192
STRUCTURE AND CLASSIFICATION OF BIRDS
There are fourteen cervical vertebre. The atlas is per-
forated by the odontoid process ; strongish median hypapo-
physes exist on vertebræ C11-D2. In Rhamphastos ariel
there is in addition a paired hæmapophysis on C10, not
present in Pteroglossus Wiedi. Five ribs reach the sternum,
which is four-notched and has a spina externa. The clavicles
are short and do not unite in the middle line; they are ex-
panded above, as in the barbets. There is a small accessory
scapular nodule, from which deltoid in part arises. The
skull is desmognathous, holorhinal, without basipterygoid
processes. The ethmoids are large and quite fused with
the descending process of the lacrymal, itself fused with
the skull wall. The vomer is truncated at its anterior
extremity.
Fam. Capitonidæ.—This family of birds, with which I
include, following GADOW, Indicator, is of the tropics, both
Old World and New.
All the members of the family that have been examined
have ten rectrices, save Indicator, which has twelve. The
oil gland is feathered, and there is an aftershaft.
The pterylosis' shows some differences in different genera ;
in all, however, the ventral tract is single as far as the
posterior end of the neck, where it divides into the two pec-
toral tracts; each of these, again, gives off, as in the toucans,
Bucconidæ, Picidæ, &c., an outer branch. This soon termi-
nates, but the inner branches are continued as far as the
cloaca. The apteria being entirely devoid of down feathers,
the tracts are easily defined, but in spite of this NITZSCH
has, in my opinion, fallen into some errors.
The typical arrangement of the dorsal pterylosis 2
(shown in fig. 91) may be considered to be that of Megalama,
and was found to characterise the species M. asiatica, M.
virens, M. Hodgsoni, M. javensis, M. Franklini. The spinal
tract is single and narrow upon the neck, thus leaving con-
GIEBEL, “ Pterylose von Tetragonops,' Zeitschr. f. d. ges. Naturw. li. 1878,
p. 377.
2 "On the Pterylosis of Certain Barbets and Toucans,' P. 2. S., 1896, p. 555.
PICI
193
.
spicuous lateral neck spaces ; behind the scapulæ it forks,
and the posterior part of the spinal tract is not in continuity
with the interior. The former is at first a single tract, but
it divides some way in front of the oil gland, which it
surrounds, as in the Picidæ and Rhamphastidæ ; but in the

.
YO
It
.
..
n
ir
CO:
.
.
a2
.
AT
.
.
O
:
.
..
WWS
11
11
.
A.
.
X.
TAXO
Att
ro
I
YI
YA
WI
.
a
>1972
.co.
z
>
HHHH
23
>
costo
50
*
rosta
t
.
il
ES
WII
Film
SOX
Sources.
Fig. 91:-FEATHER TRACTS OF Megalcena asiatica. THE RIGHT-HAND
FIGURE SHOWS THE VENTRAL SURFACE, THE LEFT THE DORSAL.
former family there is also a median continuation of the
spinal tract, which stops at the base of the oil gland. On
each side of the spinal tract is a very narrow lateral tract,
which is figured by NITZSCH as existing also in the Rham-
phastidæ and the Picidæ. Xantholana rosea shows differ-
ences from Megalama ; the spinal tract divides in the usual
way, but the tracts rejoin, so as to enclose a diamond-shaped
space; they then again diverge immediately, and end at the
sides of the oil gland in the usual way.
Xantholama has a faint lateral tract on either side. In
spite of NITZSCH's figures I am disposed to think that this
tract, so universal in the barbets, is at most feeble in the
toucans. In the continuity of the anterior and posterior
194
STRUCTURE AND CLASSIFICATION OF BIRDS
LI
1
POTT
parts of the spinal tract Xantholama is more toucan-like
than any barbet.
In Capito and Trachyphonus NITZSCH has figured an
anterior bifurcation of the posterior part of the spinal tract,
much more marked in the former genus, where, indeed, I am
inclined to suspect a more detailed resemblance to Xantho-
lema than is suggested by NITZSCH’s figure. If this is not
the case, the New World genus will be distinguished from
the Old-World genera by a double posterior spinal tract
· divided by a break from the forked anterior tract.
The tensores patagii consist of a slighter tensor longus and
a wider brevis; the tendons of both are simple, and each is
reinforced by a tendinous slip from the pectoralis. The
brevis tendon is simple, and terminates, as in the last two
families, upon the tendon of the extensor metacarpi radialis.
In Capito, at any rate, there is a cucullaris propatagialis.
FÜRBRINGER had indicated a point of difference among the
barbets which concerns the rhomboideus profundus. This
muscle in Meiglyptes (Picidæ) and Rhamphastos is a large
fan-shaped muscle, arising from the tip of the ilium, as
well as from the spinous processes of certain of the dorsal
vertebræ, and is inserted from the tip to about halfway down
the scapula. In Capito this muscle is plainly divided into
two-an anterior and a posterior--of which the latter arises
from a few vertebræ and from tip of ilium. In Megalæma
the anterior section of this muscle is itself again divided
into two quite distinct parts. This family, like the wood-
-peckers, toucans, and Passeres, has a latissimus dorso-
cutaneus, but no netapatagialis.
: The deltoid extends some way down the arm, as in other
allied birds and in Passeres; it has no special scapular slip.
The barbets, like the woodpeckers and toucans, possess a
sesamoid ossicle, called the scapula accessoria,' which is
developed in the scapulo-humeral ligament; from it arise
some of the fibres of the deltoid. This bone, again, is also
found in Passeres and owls, and in a host of other birds. The
1. See FÜRBRINGER, P. 229. Fontes laid too much stress upon its classifica-
tory value in the present case.
PICI
195
con
TU
glutæus maximus is both pre- and post-acetabular in origin.
There is no gl. externals. In the leg the formula is the
typical picarian one of AXY-. Both peroneals are present,
as in the Rhamphastidæ, and with the normal attachments.
The deep plantar tendons have been already described and
displayed (fig. 58, p. 102).
The tongue (in M. virens) is sagittate, with horny
margins, and slightly lacerated apically. In a specimen
of Megalæma asiatica the horny apex was bifid, quite
regularly so.
The right lobe of the liver in M. virens is a little larger
than the left. The greatest peculiarity of the liver, however,
II
U
"
Picidæ it is of great length and intestiniform, i.e. of narrow
and regular calibre; in a specimen of M. virens it was two
and a half inches long. The presence of a similar gall
bladder has been noted in M. Franklini and in Xantho-.
lama rosea.
The intestines (devoid of cæca) are voluminous but short.
-seventeen inches in M. virens, twelve in M. asiatica.
The syrinx of Megalæma (asiatica) is of a very simple.
tracheo-bronchial form ; the last rings do not fuse at all, but.
remain perfectly distinct; there are no intrinsic muscles.
The extrinsic muscles are attached to the tips of the costal
process.
The skull is 'ægithognathous, with a desmognathous
tendency,' holorhinal, and without basipterygoid processes.
The desmognathous tendency is shown by the fact that (in
· Megaloma asiatica) the maxillo-palatines may or may not
blend with the nasal septum. In others, e.g. Pogonorhynchus:
bidentatus, the two bones (maxillo-palatines) blend com-
pletely across the middle line. These forms are, therefore,
genuinely desmognathous, except as concerns the voner.
This bone is truncated, as in the ægithognathous skull, and
its two forward limbs join the maxillo-palatines, as in Indi-
It is single (except, of course, for the anterior bifurcation).
in Megalæma ; broader and double in Gymnobucco calvus.
196
STRUCTURE AND CLASSIFICATION OF BIRDS
As GARROD has pointed out, the vomer of the Capitonidæ
differs from that of the Passeres in being truncated behind
the posterior line of the palatines; in the Passeres the
truncation is in front of the line. The skull of Megalæma
asiatica has been described and figured by PARKER.' Outside
the Y-shaped vomer there is on each side a small 'septo-
maxillary'splint, and in front a median unpaired septo-
maxillary. The former are, perhaps, the equivalents of the
vomers of Picidæ (q.v.); the vomer in that case may have
something to do with the medio-palatine of Picus. The
nostrils are impervious and very much reduced by long
growths. In Megalæma virens and Gymnobucco the lacry-
mals and prefrontals entirely fuse with each other and with
the skull walls to form a solid and imperforate plate of bone,
as in Pterocles, pigeons, toucans, &c. .
There are fourteen cervical vertebre. The atlas is per-
forated by the odontoid. The axis and the three following
vertebræ have median hypapophyses ; the next vertebra (the
sixth) has a bifurcate one. All these processes are more
conspicuous than in the toucans, where, however, they are
present. Vertebræ C11-D6 (last) and Li have strong
hypapophyses, that of D2 being bifurcate. In Gymunobucco
only three dorsals have hæmapophyses. Five ribs reach the
sternun, which is four-notched and has a spina externa; the
clavicles do not meet below. The head of the clavicle
expands into a wide flat triangular plate.
Indicator is considered to be the type of a distinct sub-
family of the Capitonidæ, which also contains the genus
Protodiscus. Indicator has been chiefly investigated by
GARROD.2 NITZSCH, however, previously and FÜRBRINGER
subsequently added to our knowledge of the bird. It has
twelve rectrices ; the pterylosis has a marked gap between
the anterior and the posterior parts of the spinal tract; and
the latter appears to encircle the oil gland, as in the
Capitonidæ.
UU
1
L'On the Structure and Development of the Bird's Skull,' Trans. Linn.
Soc. (2), i. p. 122.
2 Notes on the Anatomy of Indicator major,'P.Z. S. 1879, p. 930.
PICI
197
The syrinx is shown in the figure on p. 61 (fig. 40). The
trachea at its lower end is formed into a bony box by a fusion
of several rings; the first bronchial semi-ring, to which
the single pair of intrinsic muscles are attached, is larger
than those which follow. The muscular anatomy, excepting
for minute details, is the same; one of these small details
is that the pectoral slip to the tensor patagii is muscular
and not tendinous.
The skull is ægithognathous; the vomer is forked in
front and joins the separated maxillo-palatines, as in
Megalæma asiatica ; but GARROD has remarked upon the
fact that in this character (the widely separate maxillo-
palatines) the palate of Indicator is more like that of the
Picidæ than are the Capitonidæ.
U
ALCEDINES
Definition.-- Aftershaft absent. Muscle formula of leg, AX. Cæca
absent. Both carotids present. Skull desmognathous.
VICU UN
The kingfishers form a natural assemblage of birds-
Alcedinidæ—which, however, show some variations in their
structure.
Thus, while they generally agree with the bulk of their
relations in having a characteristically tufted oil gland,
the genus Tanysiptera (three species at any rate) has a nude
oil gland. In this genus too the rectrices are ten, twelve
being the more usual number.
As to pterylosis, the kingfishers are characterised by the
possession of down feathers not only on the pterylæ but
also on the apteria. There is a difference between Alcedo
and Dacelo in that the latter has a weak dorsal tract in the
middle region of the back, it being stronger in front and
again near the oil gland. In Alcedo the tract is of uniform
strength throughout. The kingfishers, like the swifts,
sometimes possess and sometimes do not possess the fifth
cubital remex.
In Dacelo gigantea there are fifteen cervical vertebra ;
and only three ribs reach the sternum. In Dacebo Gaudi-
ITY
198
STRUCTURE AND CLASSIFICATION OF BIRDS
chaudi·there are fourteen cervical vertebræ, and four ribs
reach the sternum-a difference which appears to me to
justify the separation of the latter into a distinct genus,
Sauromarptis. Halcyon smyrnensis agrees in these points
with D. gigantea.
The last cervicals (from 101) and the dorsal vertebræ.
(including the first lumbar) have well-developed, often
bifurcate, sometimes trifurcate hæmapophyses. The four-
notched sternum has a well-developed spina externa.
As Dr. CUNNINGHAM has pointed out, the lacrymals of
Dacelo are larger than those of Ceryle,2 and, I may add, of
Halcyon and Todirhamphus (=Sauropatis). The skulls of
the genera above mentioned are remarkable for the fact that
the temporal fossæ as nearly as possible meet behind : there
is only a slight bridge dividing them. The lacrymal,
moreover, dilates into a wide plate, with a notch, on the inner
side of which is received the small flat-pointed prefrontal
process of the ethmoid. I have observed these skull cha-
racters in the Coraciidæ. The clavicle reaches the scapula
and gives off a longish acromial process. The nares are
impervious.
In Sauropatis albicilla, Daceto gigantea, Cittura cyanotis,
and Pelargopsis (FÜRBRINGER) the tensores patagii have
the somewhat complicated arrangement shown in the figure
(fig. 94). There are two tensor brevis tendons, of which
the anterior, after giving off a wristward slip, is continued
over the arm to the lower side, fanning out as it goes.
There is in all a passeriniform tendinous slip. Dacelo has
a muscular pectoralis propatagialis. Sauromarptis Gaudi-
chaudi and Sauropatis sanctus are quite similar. There is,
in Pelargopsis at least, a tendinous slip from pectoralis I.
to both longus and brevis tendons.
In Callalcyon rufa (fig. 93) there is a simplification,
only the anterior of the two tendons being present; the
passeriniform slip is barely marked. In Alcedo there is a
still further degeneration ;' not only is the passeriniform
i On. C10 there is a paired hæmapophysis in Dacelo.
2 SHUFELDT, “On the Osteology of Ceryle,' J. Arrat. Phys. xviii. p. 279.
ALCEDINES
199
slip absent, but the wristward slip is hardly shown. There
is a fleshy pectoralis propatagialis joining the longus tendon.
In Ceryle alcyon the two tensor brevis tendons form a
broad diffused tendon, to which is joined, before it gives off
the wristward slip, a peculiar long (hornbill-like) pectoralis
propatagialis tendon.
· In Alcyon Lessoni we have the most simple form of
tensor brevis without any branch.


.
N
LO
.
....
ad
SS
I
E
.
.
...
..
.
.
.
.
.
.
...
Fig. 92.–TENSORES PATAGII FIG. 93.- TENSORES
01 Ceryle alcyon. PATAGII Or Callal.
CYON rufa.
FIG.94.--TENSORES PATAGIİ
Or Sauropatis albicilla.
In Syma the tensor brevis consists of two tendons, but
the anterior has no wristward slip at all.
There is never a biceps slip. The deltoid has a scapular
slip.
The expansor secundariorum appears sometimes to be
absent. But it is present in Dacelo, Tanysiptera, Syma, and
Cittura. Dacelo, at any rate, has no humeral slip to the
CNConceus.
The leg muscle formula is, without exception, AX“.
In Dacelo there is but one peroneal, which is the brevis.
The deep flexor tendons vary somewhat. In Dacelo
gigantea the arrangement of these tendons is, as Professor
200
STRUCTURE AND CLASSIFICATION OF BIRDS
GARROD pointed out, precisely that of Momotus. But in
Halcyon vagans the two tendons blend completely before
the branches to the toes, all arising approximately at the
same level, are given off. The structure of the conjoined
tendon, however, seems to suggest that the flexor hallucis is
concerned with the supply of digits III., IV..
In some kingfishers there is a myological peculiarity not
found in any other group of birds. Dr. R. O. CUNNINGHAM
discovered in Ceryle stellata a strong transverse tendon
uniting the two biventri cervicis close to the upper belly of
the muscles. He failed to find this junction in Alcedo ispida
and Dacelo gigantea. Tanysiptera and Cittura! have this
link, but not Syma, Halcyon, or Sauropatis.
The following table gives the intestinal lengths of two
species :-
Ceryle amazona . . . . 24 inches
Halcyon sp..
. . 147
The right lobe of the liver seems to be always larger
than the left.
I have examined the syrinx in Dacelo cervina. The last
tracheal rings are completely fused in front to form a bony
box, which shows no traces of the number of rings of which
it is composed. These rings appear to be five or six in
number, and, with the exception of the last, are fused
together in the middle line behind. In front of this box the
tracheal rings interlock in the usual fashion. The first
bronchial semi-ring, which is ossified, is firmly united to, but
not fused with, the tracheal box; the succeeding rings are
cartilaginous. The syrinx has two pairs of intrinsic muscles;
the most anterior is the more slender; the wider muscle
arises from the trachea, just where the extrinsic muscles are
given off, and is attached to the first and apparently also to
the second bronchial semi-ring.
In Ceryle alcyon there are no great differences, but the
1 In one of two specimens of S. vagans it was present.
2 Notes on some points in the Anatomy of the Kingfisher,' P. 2. S. 1870,
p. 280. See also BEDDART), P. 2. S. 1896, p. 603.
ALCEDINES
201
rings forming the box are not so completely fused, and the
larger intrinsic muscle arises much lower down-in fact, at
the commencement of the box.
COLII
Definition.--Aftershaft present ; oil gland tufted. Muscle formula,
AXY; biceps slip present. Cæca absent. Skull desmognathous.
II
Of the family Coliidæ there is only a single genus, African
in range and including something like nine species.
The toes are remarkable for the fact that the zygodacty-
lous condition can be assumed; the first toe can be directed
forwards, the fourth backwards. There are ten rectrices ; a.
tufted oil gland and an aftershaft are present.
The pterylosis described by NITZSCH is remarkable for
the width of the pterylæ. The ventral tract almost com-
pletely covers the ventral side of the body; towards the
outside the feathers are stronger, but there is no outer branch.
The spinal tract is narrow and strongly feathered upon the
neck; on the occiput is a bare space, reminding one of that
in a similar position in the Trochilidæ. There is no median
spinal apterion.
In their myology the colies are remarkable for possessing
a fleshy biceps slip. The tensor patagii brevis muscle is very
extensive, and reaches nearly as far as the fore arm. Its
very short and single tendon sends back a 'passerine 'slip,
oblique in direction, and is also continued over the arm.
The pectoralis slips to both longus and brevis are present.
The deltoid, as in so many allied birds, is very extensive.
The leg muscular formula is AXY-. There is only one
peroneal.
The semimembranosus is inserted below and indepen-
dently of the semitenclinosus. The latter gives off a tendinous
slip to the gastrocnemius.
The deep flexor tendons blend before giving off branches
to the toes..
| Hence the term “pamprodactylous,' sometimes used for this family.
202
STRUCTURE AND CLASSIFICATION OF BIRDS
1
Besides the hornbills and Macrochires the colies are the
only flying birds in which the latissimus dorsi metapatagialis
is absent.
The colies have only the left carotid.
The stomach is not very muscular. The liver is small
and has a gall bladder. There are no cæca. The intestines
are short, but capacious, measuring nine inches.
The syrinx has been figured by JOHANNES MÜLLER. It
is quite typically tracheo-bronchial.
The skeleton and the affinities of Colius have been elabo-
rately treated of by MURIE.
There are thirteen cervical vertebræ. Four ribs reach the
sternum.
The skull is holorhinal, without basipterygoid processes,
and desmognathous. After a careful maceration GARROD 3 was
unable to find a vomer, the presence of which had been
previously 4 asserted (see fig. 95, p. 203).
TROGONES
Definition.-Feet zygodactyle by reversion of second toe. Skull
schizognathous with basipterygoid processes. Oil gland nude.
Left carotid alone present. Cæca short. Ambiens absent. Of
deep plantar tendons Fl. hall. supplies I. and II., Fl. dig. III.
and IV. Vinculum joins them before bifurcation of each.
UCU
This family is chiefly American, but also African and
Asiatic.5
The feathers of the trogons have very well developed
aftershafts. The pterylosis is remarkable for the non-
bifurcation of the spinal tract, which is continuous as a single
tract to the base of the naked oil gland. It is dilated to form
a rhomboidal area behind the scapula.
There are twelve rectrices.
1. Ueber die bisher unbekannten typischen Verschiedenheiten der Stimm-
organe der Passerinen,' Abl. li. Akad. Wiss. 1845.
? Qn 'the Genus Colius, its Structure and Systematic Place,' Ibis, 1872,
p. 263.
3 "Notes on the Anatomy of the Colies (Colius),' P. 2. S. 1876, p. 416.
By MURIE.
5 Trogon gallicus is an extinct species from the Miocene of France.
TROGONES
203
Port
hi
w
A
:
>
SUV
"
SW
.
.
ZES
www
Of the muscles of the thigh which Professor GARROD
regarded as of importance there are present the femorocaudal
and the semitendinosus, the accessories of both being absent.
The femorocaudal is proportionately larger than in almost
any bird. There is no glutæus primus. The obturator
internus is small and oval. The singular arrangement
of the deep plantar tendons
is used in the definition of
the family. The two tendons
concerned each supply two
digits, this arrangement being
unique. In the fore limb
there is no biceps slip to the
patagium. The patagial muscles
and tendons are much compli-
cated; they have been figured
by GARROD for Trogon puella.
The very powerful tensor
brevis muscle runs as a muscle
nearly to the extensors of the
fore arm; it has a short broad
tendinous insertion on to the
fascia of the outer surface of
the arm, and this is specially
developed, a line running back
to the humerus, as in the FIG.95.-SKULL OF Colius castano-
Passares Iseen7702)
Passeres (see p. 172). Deeper
Deonar rotus. VINTRAL ASPECT. (AFTER
GARROD.)
than this are two parallel
tendons : of these the one nearer the humerus terminates
exactly like the single one of the Passeres ; the other tendon
ends as in the Pici, elsewhere described. There is no expansor
secundariorum.
The tongue of the trogons is short and three-sided. It
is pointed in front. The left lobe of the liver is a little the
smaller. Among GARROD's notes are the following measure-
ments of the intestines and the cæca in three species of
trogons, which we reproduce :-

.
.
Y
.
to
1.NU
Kivi
CM
C'
HW
204
STRUCTURE AND CLASSIFICATION OF BIRDS
Trogon mexicanus ,
Tr. puella
Pharomacruis mocinno
Intestine .
Cæca .
.'10.5 inches
. 1.25 and 1 inch!
8.5 inches
1.1 inch
16 inches
1.75 inch
There is no crop; the gizzard is thin-walled and large ; the
proventriculus is zonary.
The most remarkable matter concerning the osteology of
the trogons is the curious mistake which was originally made
as to the nature of the palate. HUXLEY, in his paper upon the
classification of birds, came to the conclusion, from a single
incomplete skull of Trogon Reinwardti, that the skull was,
like its presumed allies, desmognathous. Later FORBES ' was
able to show in five species that the maxillo-palatines were
not united across the middle line, but that they terminated
in a spongy expansion some way from each other. The end
of the vomer is thin and filiform. The lacrymal is somewhat
styliform, and reaches the jugal bar; there appear to be no
ossified ectethmoids. The palatines of the trogons are
peculiar. Instead of being flat plates, as in Coracias, for ex-
ample, the outer portions of the bones are bent upwards, and
cling closely to the basis cranii. The two palatines are,
moreover, fused posteriorly, and the pterygoids where they
articulate with them are expanded. They are holorhinal
with impervious nares. The trogons have fifteen cervical
vertebra. The atlas is perforated by the odontoid process;
four or five ribs reach the sternum. The sternum has two
incisions behind, and the bifid spina externa.
La
WO
CORACIÆ
Definition.— Aftershaft present Muscle formula, AXY ; expansor
secundariorum present. Cæca generally present. Desmogna-
thous.
The Coraciidæ are entirely Old-World birds, chiefly
massed in the Ethiopian region, but extending as far as the
T'Note on the Structure of the Palate in the Trogons, P. 2. S. 1881,
p. 836.
CORACIÆ
205
9
LUCU
Australian. The genera allowed by DRESSER in his recent
monograph of the family are Coracias, Eurystomus, Brachy-
pteracias, Atelornis, and Leptosomus. They are distributed
by him in three subfamilies; the first two genera constitute
the first, the next two the second, while Leptosomus is placed
in a subfamily by itself. The rollers have an anisodactyle
foot; the feathers have an aftershaft; but the oil gland is
nude. The pterylosis has been studied by NITZSCH, FORBES,
and by myself. In Eurystomus orientalis the ventral tracts
commence as two from the very first; at the angle of the
mandible they are double. Though NITZSCH has figured
the pterylosis of the throat of Coracias garrulus as if it were
continuous, I do not find any difference from Eurystomus in
this particular. On the breast the two divisions of the
ventral tract remain single; there is hardly a trace of the
outer branch. The tracts are here rather wide. The dorsal
pterylosis narrows gradually until between the shoulders,
where the feathering is very strong, and where it divides
into two branches; these unite again just at the articulation
of the femora, and finally terminate a little way in front of
the oil gland.
Leptosomus has a slightly different pterylosis ; the
ventral tract is single to about an inch behind the junction
of the mandibular rami ; for a considerable distance the
ventral band is continuous with the dorsal, so that the
lateral neck spaces do not commence until about three-
quarters of an inch above the shoulder. About the middle
of the sternum the pectoral tract of either side gives off an.
outer branch some four feathers wide and slightly stronger
than the main tract. The two forks of the dorsal tract
run in between each other, the narrower posterior portion
between the limbs of the wider anterior portion, as is the
case with so many birds. FORBES has noted that Atelornis
has a pterylosis which agrees with that of Eurystomus,
already described.
Leptosomus differs, however, from the remaining Coraciidæ
in the possession of powder-down patches, which were first
See anatomical preface to DRESSER'S monograph of the group.
206
STRUCTURE AND CLASSIFICATION OF BIRDS
described by SCLATER. There are two patches in the
lumbar region, lying between the dorsal and the femoral
tracts.
The tongue of the rollers wants the spiny fringe at the
base which is so common a feature of this organ in other birds;
it is horny in front and entire at the tip. The liver has a
larger right lobe and a gall bladder.
The following are intestinal measurements:

Small Intestine
Large Intestine
Cæca
9 inches
i
-
Leptosomas .
Eurystomus
Coracias .
23 inches
1 inch
-
10
9
| 21, 2 inches
1 inch
2:2 inches
.
11
1
ta.
-
-
--..
.-.-.
-..-.--
6:72. br.
1
The tensores patagii of Leptosomus are figured in the
accompanying cut. The brevis tendon gives off a wrist-
ward slip just before its attach-
ment to the tendon of extensor
metacarpi radialis longus, over
which it passes to be inserted
below. There is no biceps slip.
Coracias garrulus is the
same save for the fact that
there are two separate brevis
tendons, from the first of which
the anterior gives off the
wristward slip; the inner
thinner tendon of these does not
cross the wrist. Eurystomus
does not differ. In these birds
Fig. 96.---TENSORES PATAGII OF Lep-
P there is a well-developed ex-
tosoinus (AFTER FORBES).
P, patagium ; l.p.br, tensor patagii brevis; pansor secundariorum of the
Sana fully developed type, which
Professor GARROD has called 'ciconjiform.'
The muscle formula of the leg is AXY-. The gluteus
maximus does not reach below the acetabulum; the gl.

SASSA
s
24URES
ta,D.
2 .2. R
S
. .
.
E T
*
**
A
emr.
C.m7, extensor metacarpi;l, its origin.
T'On the Structure of Leptosoinci discolor,' P. Z. S. 1865, p. 682.
? From FORBES, 'On the Anatomy of Leptosoina discolor,' P. Z. S. 1880,
p. 464.
CORACIÆ
207
externus is present in Eurystomus, represented by a ligament
in Coracics. The deep flexor tendons are of type V., where
the two tendons blend before the four branches are given off
to the toes. Both peroneals are present. The carotids of the
Coraciidæ are two. In Leptosomus FORBES found that the
two arteries run up close together, but are not fused in the
hypapophysial canal. He thinks that they may be, like
those of Bucorvus;t no longer functional as blood vessels.
The syrinx of the Coraciidæ is quite typically tracheo-
bronchial. In C. garrulus the intrinsic muscles are attached
to the first bronchial semi-ring. These semi-rings are ossified;
the rest of the bronchial semi-rings are more slender and not


.
HUO
ino.
III
1113
illll
1
TO
I WIND
!!
WWW
Tom
inget
41
nu
I
:
IM
lang
FIG. 97.-SYRINX Or Leptosomus (AFTER FORBES). THE LETT-
HAND FIGURE FROM IN FRONT, THE RIGHT FROM BEHIND.
ossified. In Eurystomus the only difference is in the fact that
the three semi-rings following the first are closely attached to
it and to each other, and appear to be ossified; after these
are the broader soft cartilaginous semi-rings. The syrinx of
Leptosomus (fig. 97) is rather different; it appears to be
an extreme development of the type found in Eurystomus.
The first three bronchial semi-rings, like the last tracheal
rings, are ossified; the first of them appears to be nearly, if
not quite, a complete ring. The fourth and the succeeding
semi-rings are cartilaginous; to the former are attached the
intrinsic muscles. In the commencing formation of a
bronchial syrinx' Leptosomus evidently gives a hint of
cuckoo affinities, to which group, however, its structure in
general does not incline..
. There are fourteen cervical vertebræ in Leptosomus,
| Cf. p. 215.
208
STRUCTURE AND CLASSIFICATION OF BIRDS
thirteen or fourteen in other Coraciidæ. The atlas (Coracias)
iş notched for the odontoid process; C2-4, C10-D2 have
hæmapophyses. On C13 and 14 there are also a pair of
downward processes (catapophyses), one on each side of the
hæmapophysis, which, in the case of C14, arise from a
common base with it and on Di from its tip.
In Eurystomus the atlas is perforated. Four (Lepto-
Somus ?) or five (some other forms) ribs reach the sternum,
which is singly or doubly notched on either side, and has a
spina externa but no spina interna. The skull is desmogna-
thous, holorhinal, without basipterygoid processes. The
rollers have the same peculiar lacrymal that has been referred
to above in the kingfishers. The bone expands enormously
below and comes into near relations, but does not fuse, with a
slight ectethmoid ; the lacrymal reaches the jugal. Another
process, whichi descends in a straight line and actually
reaches the jugal. These remarks apply not only to Coracias,
but to Eurystomus and Atelornis, in which latter, however,
the postfrontal process is not quite so long.
The family Meropidæ consists of the genus Merops, and
of a few others which have been carefully monographed by
DRESSER. Like the rollers the bee-eaters are an exclusively
Old-World family, ranging through the Palæarctic, Ethiopian,
Oriental, and Australian regions, but again, like the rollers
predominating in the Ethiopian.
As to external characters, the oil gland is nude; the
rectrices are twelve; the feathers have an aftershaft. The
pterylosis (described by NITZSCH and by myself ) is as
follows:
The spinal tract is wide, and is at first connected round
the neck with the ventral tract. About halfway down the
The osteology (and some of the viscera) of Leptosomus is described and
figured by MILNE-EDWARDS in the Histoire Naturelle de Madagascar. See also
for the family NITZSCH and GIEBEL, ' Zur Anatomie der Blauracke,' Zeitschr.
f. d. ges. Naturw. x. p. 318.
? In anatomical preface to DRESSER's monograph.
CORACIÆ
209
1
neck it becomes separate, and terminates in a truncate or
sometimes bifurcate extremity between the shoulder blades ;
at this point there is a break and the rest of the spinal
tract is double, en closing a space bounded by two distinctly
conical tracts, which gradually get narrower to their point
of fusion, a little way in front of the oil gland. The ventral
tract is double from close to its point of origin ; the two
tracts get wide upon the pectoral region, whence they
gradually dwindle to a single feather wide close to their
termination; the pectoral tracts have no outer branch.
Nyctiornis has two carotids; most of the others have
only one, the left. The bee-eaters have long caca,' like the
Coraciidæ. In a specimen of M. ornatus with the intestines.
only 54 inches they measured į inch; in a larger species.
1 inch.
The proventriculus is zonary; the right lobe of the liver".
the larger, and with a gall bladder.
The tensor patagii brevis tendon gives off a wristward
slip, and a 'passeriform' slip to the humeral at its insertion
to the fore arm, which it does not cross. There is no biceps.
slip, but there is a fleshy slip to longus from pectoralis; that.
to brevis is entirely tendinous, there being in both an
agreement with Coracias.
The deltoid extends a long way down the humerus ; it.
receives a tendinous slip from the scapula, which passes under
the latissimus dorsi and over the anconæus longus. The.
latter muscle has a humeral head, but not in Nyctionis.
The expansor secundariorum is present and ciconiine.
The leg formula is AXY-. The deep flexor tendons are:
as in fig. 55, p. 100; the flexor hallucis gives off a slip to the
hallux before it fuses with the flexor communis.
The Meropidæ have fourteen cervical vertebra. The
atlas is perforated by the odontoid process. There are
hæmapophyses on C2-4, C10-01 ; that of C14 is trifurcate.
Four ribs reach the sternum, which has two lateral notches,
of which the outer is the deeper, and has both external and
internal spina, the latter being bifid, as in Passeres and
some other birds. The clavicles have an acromial process,
S
P.
210
STRUCTURE AND CLASSIFICATION OF BIRDS
as in the kingfishers. The skull is desmognathous, holorhinal,
without basipterygoid processes. The descending limb of
the lacrymal nearly unites—is connected by cartilage—with
the slender ectethmoid, thus forming a ring. The nostrils
in the dried skull are pervious.
The desmognathism of Merops is different from that of its
allies. The maxillo-palatines are long, slender, recurved
plates, like those of passerines. They are fused in the middle
line to a broad plate of bone, but the free ends of the maxillo-
palatines extend backwards for some distance independently
of this. The palate in front of the maxillo-palatines is to
some extent vacuolate. The vomer is a single rodlike bone.
The Momotidæ ? are South and Central American, com-
prising the genera (perhaps subgenera) Momotus, Hylomanes,
Baryphthengus, and some others. They are placed by
GADOW in close association with the todies, but there are
various points in which they differ from that family, upon
which stress has been laid by FORBES. It is mainly to the
last-mentioned observer 2 and to GARROD 3 that the existing
knowledge of the family is due. The external characters of
the family show some variation; in Momotus the oil gland
is quite nude; in Hylomanes and Eumomota the apex is
furnished with a few small plumes. Momotus has twelve
rectrices ; Hylomanes, Prionorhynchus, Baryphthengus, ten.
A remarkable characteristic of the motmots are the two
central racket-shaped rectrices, which matter was investi-
gated twenty years ago by SALVIN.4 It appears that
the original account given by WATERTON of the birds nibbling
off the vanes is perfectly correct, for it was observed by
BARTLETT at the Zoological Society's Gardens. As a rule
the bird only nibbles at the two long central rectrices, but
SALVIN reports a case where a bird had sought fresh fields
.and had attacked others of its feathers. It is a very remark-
| J. MURIE, On the Motmots and their Affinities,' Ibis (3), ii. 1872, p. 383.
? Collected papers, passim.
3 Collected papers, passim, 'On the Systematic Position of Momotidæ,'
P Z. S. 1878, p. 100.
t'On the Tail Feathers of Momotus,' P. Z. S. 1873, p. 429.
CORACIÆ
211
1
ULIT
able fact that when the rectrices in question first appear
they are narrower at the points where the nibbling occurs, and
where they will be ultimately denuded, than they are else-
where. But an inheritance of this particular acquired
character can hardly be asserted.
An aftershaft is present, but small.
The tensores patagii are simple, and there is no biceps
slip. There is a fleshy pectoralis propatagialis. The tensor
brevis consists of two parallel tendons, the anterior of which
does not give off a wristward slip. The fan to the ulna arises
in M. brasiliensis and M. æquatorialis as a continuation of
the hinder of the two tendons, in M. Lessoni between them.
Hylomanes gularis agrees with the first. The anconcus has
a humeral slip. The somewhat rudimentary expansor
secundariorum only reaches the margin of the teres.
The deltoid is large; its attachment to humerus is longer
in Hylomanes than in Momotus (1-1). There is a separate
tendinous scapular slip.
The muscular formula of leg is AXY-. Both peroneals
are present. The deep flexor tendons of the motmots are
rather peculiar in their structure. It will be observed that
the slip to the hallux is given off before the flexor hallucis
joins the flexor longus.
The first gluteal (gl. maximus) is only present in front of
the acetabulum. The glutæus externus is absent as a distinct
muscle, but the insertion of glutæus II. extends so far round
the head of the femur that it may represent also the other-
wise missing muscle.
The gizzard is stronger in Hylomanes than in Momotus,
and is almost 'ptilopine’in section.
The tongue is long, bifid at the apex, and worn into fila-
ments. In the alimentary canal the cæca are absent; the in-
testines measure fourteen inches in M.Lessoni, eighteen inches
in M. brasiliensis. The right lobe of the liver is the larger,
and there is a gall bladder.
There are two carotids. The femoral vein is abnormal.
The syrinx has been described by GARROD and is figured
by him. It does not apparently differ widely from genus to
P 2
212
STRUCTURE AND CLASSIFICATION OF BIRDS
genus. The last few tracheal rings are fused, but there is
not a complete pessulus.
... The motmots have fifteen cervical vertebra. The.atlas is
perforated by the odontoid process. C1-5, C11-D3 have
median hypapophyses ; on C14-D2 are a pair of inferolateral
processes, which gradually approach the median line until
they spring from a common base in D1, and are just visible as
rudiments towards the tip of the hamapophysis of D2. In
Hylomanes there is also a double hypapophysis on C10. Three
or four ribs reach the sternum, which has (Momotus) four
foramina, oř (Hylomanes) two notches and two foramina,
and a bifid spina externa. The skull is desmognathous and
holorhinal. The lacrymals are rudimentary; the ectethmoids
are very small and do not nearly reach them. Nares
impervious, pervious in Hylomanes.
1
(
110
LD.
The West Indian todies (Todidæ) form à very distinct
family; their structure has been chiefly investigated by
MURIE 1 and FORBES.They are small birds with feet in
which the syndactylism is more marked than in motmots and
some others. The annexed cut shows that the digits IV.
and V. are united together as far as the end of the third
phalanx of the one and the second of the other. The
oil gland is tufted.
The skull is very imperfectly desmognathous. The two
maxillo-palatines are not united together; they are com-
pletely free from each other and from a median ossified nasal
septum. There seems to be no vomer. The descending
portion of the lacrymals is large and broad ; the ectethmoids,
on the other hand, are small. The interorbital septum is
widely fenestrate. There are fifteen cervical vertebræ. The
intestines are, according to Mr. FORBES, remarkably short,
not measuring altogether more than 3 inches ; on the other
hand the cæca are as remarkably long (considering the sys-
0
1.On the Skeleton of Todus,' &c., P. 2. S. 1872, p. 664.
2On some points in the Anatomy of the Todies (Todide), and on the
Affinities of that Group,' ibil. 1882, p. 442. See also REICHENOW, ' Ueber das
Genus Todus,' &c., Journ. f. Ornith. xxxi. 1883, p. 430.
CORACIÆ
213
.
:..
:
tematic position of the bird); they measure about one-third
of an inch. The cæca are narrowed at their origin from the
gut, and, as in the owls, &c., dilated apically. The deep plantar
tendons vary from the arrangement common to the group in
that the slip to the hallux is given off before the blending of
the two. The arrangement, in fact, is as in the motmots.
There is an expansor secundariorum ceasing at the axillary
margin of the teres, in the gallinaceous fashion. The syrinx
has at the middle a bony box, which is formed of three or four
bronchial rings united with about two tracheal rings. It is
che hall, Fangemex apically


파H
Ha
26 alu 43
.
Fig. 98.-Foot or Todus (AFTER
FORBES). THE DIGITS AND THE
PHALANGES ARE NUMBERED.
FIG. 99.--Foot or Monotus
(AFTER FORBES). LETTERS
AS IN FIG. 98.
only ventrally that the fusion is complete. The intrinsic
muscles cease at the last tracheal ring but one.
The Galbulidæ are a family of neotropical birds, com-
prising the genera Galbula, Urogalba, Jacamerops, &c., and
known as puff birds.
. They are zygodactyle, with a nude oil gland, twelve rec-
trices, and a small aftershaft.
The pterylosis of Galbula rufoviridis is as follows :-
The inferior tract is double from the angle of the jaw;
just before leaving the neck each tract gives off a short
branch, about six rows of two feathers, which runs on to the
214
STRUCTURE AND CLASSIFICATION OF BIRDS
margin of pectoralis. The main tract itself is also only two
feathers broad. It sends off, about halfway down sternal keel,
a short curved outer branch, which runs outwards and then
forwards towards axilla, nearly meeting a second outer branch
which is given off by the tract on opposite side to the inner
branch, already spoken of. The dorsal tract has a slight
break; the very short interscapular fork is of strong feathers
and connected with posterior part only by a very few
feathers which are weak and arranged uniserially.
The tongue is long and thin, tapering to a filament ante-
riorly ; a gall bladder seems to be absent. In a specimen of
G. rufoviridis the intestinal measurements were as follows:
s. i., 4.15 inches ; 1. i., 75 inch; cæca, :7 inch.
The Galbulidæ have an expansor secundariorum, but no
biceps slip. The tensor patagii brevis tendon of Galbula has
no wristward slip. It is merely a single tendon ; in Urogalba
there is a wristward slip.
In the leg the formula of Galbula is AXY, of Urogalba
AX, both birds, of course, lacking the ambiens. The glutaus
I. and V. are absent, at any rate in Galbula. The plantar
tendons are picine,
Both carotids are present.
The skull of the Galbulida is very like that of the Bucco-
nidæ; but there are nevertheless points of difference.
In Urogalba paradisea there is a long gap in the bony
palate in front of the conjoined maxillo-palatines, as in Bucco-
nidæ ; but the palatines are more sloped off posteriorly, and
their posterior halves are more closely in contact. The de-
scending process of the lacrymal is broader, and it is perforated
by a large foramen. In Jacamerops and Galbula, on the
other hand, the descending process of the lacrymal is very
slender.
• The ectethmoids are large and the interorbital and intra-
narial septa complete.
There are fourteen cervical vertebre; the sternum has
two pairs of incisions.
BUCEROTES
215
215
BUCEROTES
Definition.-Oil gland tufted. Muscle formula, AXY. Cæca absent.
Skull desmognathous.
The well-marked family Bucerotidæ contains at least two
distinct genera, Buceros and Bucorvus. The latter (the
ground hornbill) is entirely African ; the former, which has
been much subdivided, is both African and Asiatic.
The great casque, not always equally developed, and the
long bill, frequently serrated along its margins, and the
largely black and white or black plumage distinguish these
birds. But the small Toccus is a less typical form. The
syndactyle foot, in which the second and fourth toes are
united to the third-the latter for several joints, the former
for only one-is highly distinctive, and is repeated in the
ground-living Bucorvus.
The oil gland is tufted. The feathers have no aftershaft..
There are ten rectrices.
The pterylosis of Bucorvus abyssinicus has been described.
and figured by NITZSCH.
The neck is completely feathered, except at its lower end,
both dorsally and ventrally. The former is the commence-
ment of the very narrow dorsal space of a long oval form,
but not extensive. The pectoral tracks diverge at end of
neck, but are subsequently undivided.
The carotids are double in Bucorvus ; the left only is.
present in others. The remarkable obliteration of the
carotids in the former genus, and their replacement by a pair
superficial in position, have been described by GARROD 2 and
OTTLEY.3
The tensores patagiż are in some ways characteristic of
the Bucerotidæ. In Buceros convexus (cf. FÜRBRINGER)
I OWEN, 'On the Anatomy of the Concave Hornbill,' P. Z. S. 1833, p. 102.
2 • On a Peculiarity in the Carotid Arteries ... of the Ground Hornbill,
P. 2. S. 1876, p. 60.
$o A Description of the Vessels of the Head and Neck in the Ground Horn-
bill,' ibid. 1879, p. 461.
216. STRUCTURE AND CLASSIFICATION OF BIRDS
.
14
.
w
!
.
www
www
11
II
V
SH
IND
N
.
.
there is no patagialis longus. The brevis receives rather
low down a very strong slip from the pectoral; near to its
insertion it gives off a wristward slip, which is attached to a
special tendon arising from the lower end of the humerus..
The main tendon passės over this, not attached to it, to the
ulnar side. The absent longus is represented only by a
thinnish tendon arising from the pectoralis.
The same structures are found in B. malabaricus, B.
coronatus, B. bicornis, and in
Toccus. In B. atratus there
is in addition an excessively
small patagialis longus muscle,
arising with brevis and con-
sisting indeed of but very few
fibres. In Bucorvus, on the
other hand (fig. 100), the tensor
patagii longus is well developed.
Each tendon has a slip from
pectoralis (a and a' in fig. 100),
but that which joins brevis
receives a tendinous slip from
the biceps. This, however, as
it is not figured by FÜRBRINGER,
is possibly individual.
Quite exceptionally-among
anomalogonatous birds--many
PATAGIAL MUSCLES OF hornbills have a broad humeral
i Bricorvus (AFTER BEDDARD).
HI, humerus; Bi, biceps; Bs, biceps slips (?);
attachment of the anconaus.
in ; a, «e'The muscle itself arises from
the scapula by a Y-shaped
(Bucorvus, Buceros) or flat, non-divided (Aceros) head. The
humeral 'ankerung' is found in B. subcylindricus, B. bicor-
ris, not in B. elatus, B. malabaricus, B. atratus, Bucorvus
abyssinicus, Aceros, or Toccus. The deltoid has no scapular
slip.
· The lég formula of all hornbills is AXY-.
.: The glutæus maximus is quite. absent; the glutæus ex-
ternus is only present as a ligament.

..
.
Whili lilimilimiiniline
w
www
www
ww
ucul.
www
m.
RiE.H.
6.1, 1.2, tensor patagii brevis tendon ;dl, a',
..slips from pectoralis.
On
10
BUCEROTES
217
- The biceps is occasionally (e.g. B. elatus) double at its
origin, the tendons being separated by quite a quarter of an
inch.
The arrangement of the semitendinosus and adductor in
Aceros nipalensis, which is somewhat complex, will be
understood from the accompanying drawing (fig. 101).
• The semitendinosus (St) is inserted on to the tibia by a
long, thin, flat tendon; another tendon, joining the first just
where it passes into the muscle, is attached to the gastro-
cneinius.
The accessory semitendinosus is in two parts: the larger
half (Ast) is attached to the semitendinosus just behind the
origin of the tendon of insertion of the latter ; the second
half appears to arise from the tendon which connects the
semitendinosus with the gastrocnemius, it passes up towards
the thigh, and just in front of its (tendinous) insertion on to
the femur it receives a tendon from the adductor. This
latter muscle (the adductor longus) is inserted by three
tendons(1) to the femur; (2) a small tendon which has
already been described as joining the second half of the
accessory tendinosus; and (3) near to the origin of one of
the internal heads of the gastrocnemius; to this tendon is
also attached the inner head of the gastrocnemius.
The corresponding muscles of Bucorvus abyssinicus are
rather simpler than in Aceros nipalensis. The adductor
longus is only inserted at two places : first, by a fleshy inser-
tion along a considerable length of the lower border of the
femur; second, by a tendon in common with the inner-
most head of the gastrocnemius. The semitendinosus is
attached by a thin tendon to the tibia, as in Aceros, and by a
short tendon, also as in that species, to the gastrocnemius.
The accessory semitendinosus arises chiefly from this latter
tendon, but there is no division between this part of the
muscle and that which takes its origin from the fleshy part
of the semitendinosus.
'In Buceros atratus there is, again, some little difference
1 Gadow figures most of these muscles in Bronn's Thierreich, '. Aves,' Bd.
vi. Abth. iv. Taf. xxiii. b, fig. 1.
218
STRUCTURE AND CLASSIFICATION OF BIRDS
.
from both the types already described, although the resem-
blances are on the whole closer to Aceros.
The adductor longus is attached by two tendinous heads;
the upper one of these, as in Aceros, is attached to the lower
border of the femur; this corresponds to the fleshy insertion
of the muscle in Bucorvus; the lower tendon is fused on its
way with the inner head of the gastrocnemius, which is
continued upwards and reaches the femur, and then bifur-
cates into two tendons of insertion. The relations of the

www.
ht.
www.
w
www
ww.
www
.
.
etter
.
.
.
Nr 11
///
IIIIIIIIIII
Alth
LUI
.
wwwww
wwwwww
-
-
wwwwwww
nda
.
.
2
.
UM
III
/2001
.
I
ww.
w
SE
ESSAARE
1
Sil.
gast - AWAN
FIG. 101.—LEG MUSCLES OF Aceros (AFTER BEDDARD).
add, adductor ; Si, semitendinosus; Ast, its accessory; Sm, semimembranosus ;
gast, gastrocnemius.
semitendinosus and of the accessory semitendinosus are as
in Aceros nipalensis.
In Toccus these muscles are much the same as in
Buceros.
In Ceratogymna elata I find a closer resemblance to
Aceros than to any other of the genera mentioned in this
paper, but there is an agreement with Bucorvus in the fleshy
insertion of the adductor longus on to the lower border of
the femur. The accessory semitendinosus is distinctly double,
as in Aceros, and is attached by a short tendon to the
BUCEROTES
219
2
0
adductor, though the direction of this tendon is somewhat
different from what is found in Aceros.
The skull is doubly desmognathous. There are distinct
basipterygoid processes, large in B. rhinoceros, almost va-
nished in A. nipalensis, with which, however, the pterygoids
do not articulate. The interorbital septum is widely fenes-
trate. The fused lacrymals and ectethmoids together make
a large plate of bone; the postfrontal processes are large.
The atlas is fused with the axis. The håmapophyses are
slight. There are fourteen or fifteen cervical vertebrae ; they
are median in C12-D2. C14 and Di have a median and
two lateral processes. The sternum, which is faintly two-
or four-notched, has both spina externa and interna.
• The liver lobes present some differences in different
hornbills.
Commencing with Bucorvus abyssinicus, in which the
right lobe is larger than the left, the series terminates with
Buceros coronatus, in which the left lobe is larger than the
right. The following table shows the relations of the liver
lobes in such hornbills as have been examined :--
Bucorvus abyssinicus.
R>L.
Aceros nipalensis.
R>L
Buceros bicornis.
R>L.
Sphagolobus atratus.
R>L.
Bycanistes subcylindricus.
R>L.
Buceros plicatus.
R=L.
Buceros rhinoceros.
Buceros coronatus.
R<L.
I have noticed a peculiarity in several species of horn-
bills which is not found in all other birds. In all birds the
two lobes of the liver are completely separated from each
other by the umbilical ligament, which bears the umbilical
vein (this appeared to be particularly large and well deve-
loped in all hornbills which have been dissected by me); and
in addition one liver lobe-the right--is commonly separated
from the abdomen by a thin membranous septum. In horn-
bills both lobes of the liver are thus shut off; I have figured
- In Dichoceros bicornis there is a tendency towards the formation of a
hypapophysial canal.
Let U U U U U U
R=L.
220
STRUCTURE AND CLASSIFICATION OF BIRDS
EV1
SSSS
EMEDEWERE
VEL
ant
En
GIN
Culo
til
H
ONO
.
Edit
LS
hitam!
this condition in Bucorvus abyssinicus ; ? it is exactly the
same in one or two other species which I have subsequently
studied.
The Syrinx, Aceros nipalensis:—The last rings of the
trachea are fused together to form a solid box, at the sides of
which, however, the individual rings are recognisable. In front
the last three rings are thus fused, but behind two additional
rings fuse with the others to form a wide and deep bony
plate. The tracheal rings lying in front of these five show
the dovetailing arrangement which is so often found in the
tracheal rings. The pessulus is well developed and bony,
but, owing to the complete fusion of the tracheal rings both
posteriorly and anteriorly,
it is impossible to say
from which rings it is de-
veloped.
The intrinsic muscles
of the syrinx are attached
near to the boundary line
between the last and the
penultimate tracheal
rings.
The bronchial semi-
rings are cartilaginous, and
there is a considerable in-
terval between the first of
Fig. 102.-SYRINX OF Aceros nipalensis. these and the last tracheal
FRONT VIEW. (AFTER BEDDAND.)
ring
: Bucorvus abyssinicus.—The syrinx of this hornbill (fig.
103) differs in many particulars from the last. The tracheal
rings are not ossified, and there is no box formed by their
fusion. Only posteriorly are the penultimate ring and
the two in front of this fused just at the origin of the
pessulus; anteriorly the pessulus is fused with the ante-
penultimate tracheal ring, which forms with it a three-way
piece; the last two tracheal rings do not meet in front. The

Milly (!!!
Ciwan
SUSHI
11
FW
otti
II.
IKTI
.
mu
US
Willillllllimit
CO
cards
.
ER
Srbi
101
Us
ATE
.
212
1
HIS
HDD
DAS
21
HEN
5 .
Touc
[Notes on the Visceral Anatomy of Birds. I. On the so-called Omentum,'
P.Z. S. 1885, p. 842; and above, p. 44, fig. 29.
BUCEROTES
221
slender syringeal muscles are attached to the anterior margin
of the last tracheal ring. .
The peculiar-shaped tracheal rings are hardly recognis-
able until about the fourteenth from the end.
Buceros rhinoceros has a syrinx which is not very
different from that of
Aceros. The same rings

ZI
SM
FL
.
Y
sil
09
rt.
12
we
whom
HITO DE
V
SER
i
.
SS
05
+
17
VA
11
W
*
.
DERECE
till
IN
Los
II
*
9
UNINO
FROM
Il
.
At
S
mu
VO
abi
WA
www
17.1
IN
REH
lim.
sified box; but the fusion
between the several rings
is hardly so extensive as
in Aceros ; furthermore
the syringeal muscles are
attached to the posterior
border of the last tracheal
ring.
In Sphagolobus atra-
tus there is very little
fusion between any of Fig. 103.-SYRINX OF Bucorvus abyssini-
cus. FRONT VIEW. (AFTER BEDDARD.)
the last tracheal rings;
the last three rings, which alone show any signs of ossification,
are fused for a very short space anteriorly ; posteriorly there
is no fusion at all, and the pessulus can be plainly seen to be
connected with the antepenultimate ring. Although the last
tracheal rings are not fused, they are very closely applied
together, and no membranous interspaces are left.
Ceratogymna elata, which is, like the last, a compara-
tively small species, has a very similar syrinx; indeed, I can
find no differences sufficiently tangible to be described.
ft
In
species, hardly present any differences from B. rhinoceros.
Bycanistes subcylindricus has a syrinx which; although
of about the same size as that of Ceratogymna elata, shows
certain differences which are worth putting on record. In
the first place, the syrinx is much compressed from side to
place, the last tracheal ring is very much more arched than
usual; it forms, indeed, almost a complete semicircle. The
222. STRUCTURE AND CLASSIFICATION OF BIRDS
intrinsic muscle of the syrinx in this, as in the other smaller
hornbills, is very much larger relatively than in the larger
species.
Anthraceros malayanus, again, is a little different from
all the types hitherto described. The last tracheal rings are
but little fused posteriorly; only the penultimate and ante-
penultimate rings are so fused, so that it is impossible to be
certain as to the origin of the pessulus. The intrinsic muscles
are slender.
Toccus presents certain peculiarities which I have not
yet observed in any other hornbills ; the trachea has two
pairs of extrinsic muscles, given off about half an inch apart.
This condition seems to me to be so remarkable that I have
preserved the specimen which shows it, though unfortunately
the insertions of the anterior pair of muscles are lost, and I
have no recollection of where the point of insertion was.
The intrinsic muscles are relatively small. There appears
to be no fusion between any of the tracheal rings.
Cryptornis of the upper Eocene of France is held by
MILNE-EDWARDS to be a hornbill.
The family Upupidæl contains only the well-known
hoopoe (Upupa) and the but little known Irrisor: and
Rhinopomastus. .
There is a large feathered oil gland, but the aftershaft is
absent or rudimentary. There are ten rectrices.
The feather tracts are narrow. The ventral tract divides
very early on the neck, and gives off on each side in the
pectoral region an outer branch. At the base of the neck a
triserial tract is given off to the humeral tract, and just
below it à uniserial tract to the patagium. Between the
outer and inner branches of the ventral tract is a single row
of feathers.
The dorsal tract encloses a spindle-shaped space, the
pterylæ enclosing which are somewhat dilated in the middle.
ISTRICKLAND, On the Structure and Affinities of Upupa and Irrisor,' Ann.
Mag. Nat. Hist. xii. (1843), p. 238; MURIE, 'On the Upupide and their Rela-
tionships,' Ibis, (3) iii. 1873, p. 181.
BUCEROTES
223
The tendon of the tensor patagii longus! gives off a
wristward slip; the main tendon crosses the fore arm.
There is a cucullaris patagialis, besides slips from the
pectoralis, but no biceps slip.
The anconcus has an attachment to the humerus.
In the hind limb the formula of the muscles is the
typical picarian AXY—. The passerine character shown by
the existence of a well-marked cucullaris propatagialis is
paralleled in the hind limb by the absence of any vinculum
between the deep flexor tendons.
The tongue is short and the intestines are without cæca.
The left carotid alone is present.
There are fourteen cervical vertebra. The sternum has
a single pair of notches or fenestra and both spinæ. · The
skull is pseudo-holorhinal, desmognathous, without vomer
and basipterygoid processes.
The conjoined maxillo-palatines are rather delicate fenes-
trated bones, and the bony palate for a little way in front
is somewhat vacuolate. The palatines have long postero-
external angles, which reach back to a point corresponding
to rather beyond the middle of the pterygoids.
The lacrymals are small and ankylosed to the skull.
The ectethmoids are very large plates, and the distal end is
segmented off, and is apparently the equivalent of the
os uncinatum of many other birds; it reaches the jugal. I
describe the nostrils as pseudo-holorhinal, because, though
rounded at their extremities, they are unusually long, and
reach, or very nearly reach, the ends of the nasal processes.
They are obliterated in the middle by bony alinasals. There
is a largish median ioramen? a little way above the foramen
magnum, and a minute one just above the latter.
| Nitzsch and GIEBEL, · Zur Anatomie des Wiedehopfs,' Zeitschr. f. d. ges.
Naturw. x. p. 236.
2 This was present in only one of three specimens, in which also alone the
os uncinatum was present. It has a shorter bill and may be a different
species.
224
STRUCTURE AND CLASSIFICATION OF BIRDS
MACROCHIRES
Definition.--Rectrices, ten ; oil gland nude; aftershaft present. Muscle
formula of leg, A-, Expansor secundariorum, sterno-coracoideus,
and biceps slip absent. Cæca absent. Manus very long. Sternum
unnotched.
VU
This group of birds contains two well-marked types--
the humming birds and the swifts, the former confined to
America, the latter world-wide in distribution.
In external characters the generally minute size, the
frequently brilliant metallic plumage, and the long slender
bill distinguish the Colibris from the swifts. But Dr.
SHUFELDT has found ² in a nestling humming bird a bill
hardly longer than that of a swift.
The rectrices are ten, and in all these birds the oil
gland is nude. There is an aftershaft. In the swifts there
are down feathers upon the apteria ; in the humming birds
there are not.
The pterylosis of the group has been chiefly studied by
NITZSCH, to whose account Dr. SHUFELDT has added details
of value.
The throat is completely feathered in the swifts, the two
ventral tracts, however, becoming distinct at the beginning
of the neck. The ventral tracts widen out in the pectoral
region, but there is no outer branch or trace of one. The
narrow dorsal tract bifurcates between the shoulders and
reunites again to enclose a narrowish spinal space. There
are well-marked femoral tracts.
In the humming birds the ventral tract is double up to
the symphysis of the mandibles, or nearly so; the dorsal
tracts are very much wider and form a diamond-shaped patch,
within which is a very slight dorsal apterion ; there appear
to be no femoral tracts, and there is a naked space in the
nape of the neck, dividing the dorsal tract.
? GIEBEL, ' Ueber einige Eigenthümlichkeiten in der Organisation der Koli-
bris,' Zeitschr. f. d. ges. Naturw. 1. 1877, p. 322; W. K. PARKER, ' On the Sys-
tematic Position of the Swifts,' Zool. (3), xiii. 1889, p. 91.
? “Studies of the Macrochires,' &c., J. Linn. Soc. 1988.
MACROCHIRES
225
The swifts are among the very few birds which are
partly quintocubital and partly aquincubital.
Among the more obvious external characters are the
magnificent metallic colours which are so usual a feature of
humming birds. It is on account of the latter character
mainly that they have been placed in the neighbourhood of
-or more properly confused with the Nectariniidae. It is,
however, practically the universal opinion that these two
families have no near relationship, and the feathers of both
have been lately submitted to a careful examination by
Miss NEWBIGGIN.) The metallic colours of humming birds
occur in both sexes, though more brilliant in the male; they
are mainly to be found on the throat and on the head as a
crest. It has been pointed out that the rapidly vibrating
wings would destroy all advantage (in sexual selection) of
the development of these tints upon the wings. The colours
are of every shade, and gold and red are often present, two
colours which are not found among the Nectariniidæ. The
striking difference between the two families, however, consists
in the fact that while the Nectariniidæ have the ends of the
barbs affected by the metallic colour it is the basal part of
the barbs which is so coloured in the humming birds.
Hence the barbs have cilia in the latter case and not in the
former ; for this reason the rectrices in the humming birds.
can show metallic colours and yet not have their efficiency
as flight feathers destroyed. The interlocking apparatus.
is there in the form of the cilia. The barbs which are
thus metallically coloured are in both groups of birds.
(and in other birds which show the same kind of colora-
tion) composed of a series of roof-shaped laminæ, in the.
cavities of which the dark brown pigment essential for
the due production of the metallic colour is located.
Further details may be found in the interesting memoir
cited.
The tensores patagii show a striking resemblance among
1. Observations on the Metallic Colours of the Trochilida and the Necta-
: riniidæ,'P. Z. S. 1896, p. 283.
the swifts and humming birds. In Chætura, Cypselus, and
Phaëthornis and other humming birds the tensor brevis is
fleshy for almost its whole extent. In Dendrochelidon
the tensor brevis has still a larger muscular portion than is
usual, but the tendon is more evident and has a passerine
slip to the humerus. In the Trochili, however, the muscle
is inserted on to a special tendon upon the fore arm,” and
not on to the extensor metacarpi. In the leg muscles
the birds of this group agree in only possessing the femoro-
caudal of those used by GARROD in his classification ; the
formula, therefore, is A-, GARROD, however, has left a
note to the effect that in Chætura caudacuta the femoro-
and ischium, which is thus possibly a combined semitendi-
nosus and semimembranosus.
Though the semitendinosus is as a rule absent, there
seem to be traces of its accessory in a few swifts. Thus
in Cypselus alpinus and Chctura Vauxi the gastrocnemius
has an origin between the biceps loop and the main body
of the sciatic nerve from the femur.
Another peculiarity in the leg of certain swifts (cf. also
Phaëthon) is the absence of a biceps loop; but the value of
this character may be gauged from the following table :-
Without Biceps Sling
With Biceps Sling
Chætura caudacuta
Chætura spinicauda
Panyptila melanoleuca Chætura zonaris
Dendrochelidon coronata Cypseloides fumigatus
Macropteryx mystacea, Cypselus alpinus
The biceps femoris of humming birds—at any rate of
Patagona gigas—is peculiar in the fact of its being two-
headed.
The deep flexor tendons in the swifts vary. In the
majority of forms the two tendons completely blend; in
For Cypselus muscles see NITZSCH-GIEBEL, «Zur Anatomie d. Mauer-
schwalbe,' Zeitschr. f. d. ges. Nat. x. 1857, p. 327.
2 This tendon looks like a degenerate representative of the abductor
pollicis.
MACROCHIRES
227
Macropteryx, however, Lucas1 has described the flexor
hallucis as going to the first digit only after giving off a vin-
culum to the tendon of digit IV. As to the humming birds,
there has been some confusion. It appears, however, that
the flexor hallucis before going to digit I. gives off a slip to
flexor communis of digit II., and (according to GADOW 2)
III. and IV. also. .
Both swifts and humming birds have, as a rule, only one
carotid, the left. The following swifts have two carotids :
Chætura rutila (right carotid larger), Cypseloides fumigatus.
In Micropus (? Panyptila) melanoleuca SHUFELDT has
described the left carotid (the only one present) as crossing
over to the right and being until the middle of the neck free
of the hypapophysial canal.
The chief peculiarity of the vascular system concerns the
femoral vein. In Panyptila melanoleuca and in Chctura
zonaris the femoral vein, instead of running deep of the
femoro-caudal muscle, comes to join the sciatic artery and
nerve immediately it has passed the obturator externus
superficial to the femoro-caudal tendon ; Cypseloides fumi-
gatus is the only other swift which has been shown to be
characterised by this structural abnormality.
The large size of the heart of the humming birds as
compared with that of the swifts is commented upon by
SHUFELDT.
The syrinx of the swifts is not in any way remarkable ;
it is tracheo-bronchial, with the usual pair of intrinsic and
extrinsic muscles. The former are attached (at any rate
in Chcetura caudacuta) to the first bronchial semi-ring. In
Cypseloides fumigatus, however, a swift which is in other
ways abnormal, there appear to be no intrinsic muscles.
The humming birds, on the contrary, have an unusual
form of syrinx, which is remarkable in two ways.
In the first place the trachea bifurcates very high up in.
the neck, recalling the characteristics of Platalea rosea (see
below). Each bronchus in Trochilus colubris (according
In
13
DI
UUU
| Ibis, 1895, p. 298.
? Ibid. p. 299.
Q
2
228
STRUCTURE AND CLASSIFICATION OF BIRDS
17
to MACGILLIVRAY 1) has as many as thirty-four rings, which
are complete and not semi-rings. There seem to be two
pairs of extrinsic muscles, which form a very prominent
muscular mass, as in Passeres. Dr. SHUFELDT was unable
to find any sterno-trachealis.
The tongue in the swifts. is short and sagittate, with
a spiny base. It is constantly bifid at the tip. .
In the humming birds, as is well known, the long tongue is
tubular, and for its support the hyoids are bent over the top of
the skull, as in the woodpeckers. The tongue itself “is double
right down to the unpaired part of the os entoglossum,
whilst each of the two distal prolongations of the entoglossal
bone or cartilage is surrounded by a horny sheath, which is
curled upwards and inwards, in a similar fashion to what
we have seen in the Nectariniidæ. In many species the
outer and inner edges of these tubes, however, are entire
and not laciniated. Thus the Trochilidæ have developed
the highest form of tubular tongue' (GADOW 2).
The gizzard of the humming birds is remarkably small;
that of the cypselids presents no remarkable characters,
and SHUFELDT has remarked upon the large size of the
liver in the humming birds as compared with the swifts ;
in both the right lobe is larger than the left, and there is a
gall bladder in the swifts.
Cæca are entirely absent in the Macrochires.3. The
following are intestinal measurements of the swifts :-
Cypsélus apus: : . . 625 inches.
Dendrochelidon coronata . . . 4:30 ,
Chcetura caudacuta . . . . 10 :
Cypselus alpinus . s i in . 10
Chatura Vari .
; : 3:25 ,
A careful account of the trochiline and cypseline skeleton
will be found in a inemoir by SHUFELDT.4 Though this
. ' In AUDUBON'S: Birds of N. Amcrica.
? . On the Suctorial Apparatus of the Tenuirostres,' P. 2. S. 1883.
3 CRISP, On some Points relating to the Anatomy of the Humming Bird
(Trochilus colubris),' P. Z. S. 1862, p. 208, observed a 'rudimentary appendix.'
to Contribution to the Comparative Osteology of the Trochilidæ, Caprimul-
MACROCHIRES
229 ·
...
Prix:
V
Y
-
..
Vo
-
10.
.
Y
.
ta
1
.
-
:
.
..
.
.
LUX.
Kru
.
.
.
.
IST
1.4.
.
.
-
.
.
-
1.
K
.
.
.
.
.
Ty TASR
.
.
observer is disinclined to allow a very near affinity between
the birds, it is undeniable that there are resemblances. : :
The skull is schizognathous in the humming bird,
ægithognathous in the swifts. But the ægithognathism in
the latter is a little abnormal. GARROD has pointed out in
describing the osteology of Indicator that that bird, in
common with the Capitonidæ, has a truncated vomer, in
which the truncation occurs behind the line joining the
maxillo-palatines, while in the true
Passeres the truncation is in front of
this line. The swifts are intermediate,
the truncation being, as is shown in
the accompanying figure (fig. 104),
about on a level with the line joining
the maxillo-palatines. It is true that
the lateral processes so characteristic
of the agithognathous skull are better
developed in the swifts than in the
swallows; but, on the other hand, it go
must be borne in mind that the un-
doubtedly ægithognathous Indicator
is without these processes. In both
FIG. 304.--SKULL OF Micro-
swifts and humming birds the skull is pus melanoleucus. Under.
holorhinal and without basipterygoid VIEW.
processes. As to the vomer, palatines; vo, vomer; Na,
HUXLEY described it as truncated ; goid.
but SHUFELDT finds it to end in an
excessively fine point. In swifts the vomer is, as already
stated, truncated. But as to this difference 'and its value as
a means of separating the birds cf. the manifold vomer of
Limicolæ.
The humming birds have fourteen or fifteen (Trochilus
Alexandri) cervical vertebra. The Cypselidæ have thirteen
or fourteen. Four ribs 2 join the sternum on each side

1
A
B
17
.
**
......
.....
12:15
CR SHUFELDT.)
Pmx, premaxilla; Mirp, maxillo-
nasal; Pl, palatine; Pl, ptery-
gidæ, and Cypselidæ,'P.Z. S. 1885, p. 886, and 1886, p. 501. See also ZEHNTNER,
Beiträge z. Entwicklung von Cypselus melba,' Arch. f. Naturg. lvi. 1890, p. 189
(transl. in Ibis, 1890, p. 196).
I Loc. cit. (on p. 196.)
2 FÜRBRINGER says five or six.
230
STRUCTURE AND CLASSIFICATION OF BIRDS
in both groups of birds. The sternum in both is unnotched
and broader behind than in front.
In the fore limb the length of the hand distinguishes


N
CM
9
ZzZWA
w
ve
-
.
.
-.
-
-
-
PS.
WMO
.
2
N
21:
1
..
.
/
.
...
.
.
/
..
.
..
.
.
*
*
.
.
Sect
.
.
mo
I
1M
I
..
.
TA
.
.
fil..
.
.
***
!
IR..
.
.
HD
.
.
JI!
Poti
À
MW
-
.
-
-
1
.
.
Fig. 106.—PALMAR ASPECT OF SAME
BONE (AFTER SHUFELDT).
FIG. 105.-ANCONAL ASPECT OF LEFT
HUMERUS OF Micropus melanoleu-
cus (AFTER SHUFELDT).
2.1, pneumatic fossa.
name. The nearest approach in length of hand is shown
in the swallows, petrels, and, oddly enough, in the penguins.


.
:11
USERS
V
1.
PR
Pof
Z
HALA
N
u
Se
FIG. 107.-ANCONAL ASPECT OT LEFT Fig. 108.-PALMAR ASPECT OF SAME
HUMERUS OF Trochilus Alexandri
BONE (AFTER SAUFELDT).
(AFTER SHUFELDT).
p.f, pneumatic fossa.
The humerus in both families is extremely short; the radial
crest is well developed in both into a long process which
curves over the shaft in the Trochilidæ, but over the head in
the swifts.
CAPRIMULGI
CAPRIMULGI
Definition.--- Anisodactyle. Oil gland nude.' Rectrices, ten.' Aquinto-
cubital. Aftershaft present. Skull bolorhinal. Both carotids
present. Cæca? large. Ambiens and accessory femorocaudal
absent. Deep flexor tendons of type V.
This group of birds shows a considerable amount of
structural variation, which allows of the separation of the
genera into at least two families; they are, however, all
united by the characters in the above definition. The


Fig. 109.-LEFT FEET OF Antrostomus FIG. 110.-RIGHT FOOT or Podlar.
vociferus (RIG HIT-HAND FIG.) AND gus Cuvieri (AFTER SCLATER).
Nyctidromus albicollis (AFTER
SCLATER).
external aspect too of these birds, with the widely gaping
mouth and their generally softly tinted grey and brown
plumage, enables them to be readily distinguished from other
groups.
i Sometimes said to be absent in Podargidæ, but FÖRBRINGER found it in
Batrachostomus.
2 Absent in Ægotheles.
232.
STRUCTURE AND CLASSIFICATION OF BIRDS
In the typical Caprimulgidæ (fig. 109) the claw of the
middle toe is serrated and the fourth toe has but four pha-
langes. There is no serration and five phalanges in others.
The aftershaft is present; in the aberrant Steatornis it is

2
.
TO
1
TAS
be
1
V
X2172
.
.
9.
.
.
O
.
. *
,...
.
em
...
..
.
SALUD
VWV
What
BERITA
I'NIN
IN
XORT
..!
Nimi
..
VA
Kyn.
.
.
02.
AMESE
ciu
MADOVAN
1
:3
T
When
2
MCINNAMOMUTANIUM
Can.
35483 ROOL
TAV
.
.
.
'.,
*
W
D
.
.
INVOLVINTER
ESAI
*
-
UT
S
.
ANNA
SA
Sey
BREZ
.
.
Photo
SUS
M
otel
..
.
22
1
RE
.
.
REWAY
KARIN
VM.
SZ
WY
A.
.
el
.
.
V
TE VINY
NU
.
Am
23
Uom
**
.
66
www.
ANTOS
ANONS
KAPATIA
w
PO
WT
WA
MS
OUTLAWI
a
st
.
V?
-
AAN
H
CA
www
REHR
.
.
.
:
.
.
.
VAC
PAY...
*
S
AK
.
.
.
DONNA
.
21
1.17
S
IN
*
A
SUWOY
RE
TSXSYS
**
**
.
A
*
C
ANCE
NAIS
.
.
LO
LA
YA
www
"
W
w
ANN
37
.
-
St
2
11
.
4N
.
STAS
ELE
....
.
..
.
wa
w
12
N
.
.
.
O
.
SIN
...
.
d
.
SENAT
ar
.
.
*
w
.
.
-
*
-
LES
-
#
-
.
...
..
.
.
wa
.
es
OR
ot
VA
*
www.
2
.
-
ONS
!
Sa
.
1
9
.
YE
UN
MAR
Siz
SCO
2
.
.
1
.
S
"
WA
SS.
SS:
CSS
Katha
FIG. 111.— POWDER-DOWN PATCHES OF Podargus (AFTER SCLATER).
not absent (as GARROD asserted). Podargus is remarkable
for the possession of powder-down patches, of which there are
two, one on either side of the rump (see fig. 111), first dis-
covered by Mr. SCLATER.? The patches of this bird are well
defined and very compact, and have not the diffuse character
that is seen in, for example, Rhinochetus. Powder downs
are also found in Batrachostomus and Nyctibius. The
ISCLATER, · Notes upon the American Caprimulgidæ,' P.Z. S. 1866, p. 120.
2 ' Additional Notes on the Caprimulgidæ,' ibid. p. 581.
CAPRIMULGI
233
pterylosis has been elaborately described by. GARROD, for.
Steatornis ;? so we shall select that bird, though it is, as
att
There
.
N
.
U
.
d
C
- PTERYLOSIS or Steatornis (AFTER GARROD). THE RIGHT-HAND FIGURE REPRESENTS THE DORSAL VIEW ;
THE LEFT, VENTRAL.

COS

.
.
.::.U.
Ah
1
.
1
.
:
11
FIG
? For notes on Steatornis see, in addition to papers quoted, N. FUNCK,
"Notice sur le Steatoriris caripersis,' Bull. Ac. Belg. 1844, p. 371; F. STOLZ-
MANN, Observations sur le Steatornis Péruvien,' Bull. Soc. Zool. France,
v. 1880, p. 198; HUMBOLDT, . Sur le Steatornis,' Bull. Soc. Philor. 1917, p.51 ;
234
STRUCTURE AND CLASSIFICATION OF BIRDS
already hinted, in many ways an aberrant form as a type.
The dorsal tract (see fig. 112) gradually narrows as it
passes down the neck, but the feathers get stronger; it
bifurcates between the scapulæ to form a well-defined
fork, which ends ultimately, having become weaker. Between
this fork, and not connected with the rest of the dorsal tract,
appears a spear-headed patch of feathers. The shaft'
of the 'spear' becomes stronger as it descends to end
abruptly at the base of the oil gland. The ventral tract
is narrow between the mandibles ; it is undivided upon the
neck. At the beginning of the breast it divides into a wide
outer and a narrow inner portion, the latter being more
strongly feathered. The two converge on each side towards
the cloacal aperture, but do not reunite.
In Caprimulgus, on the other hand, the ventral tract bifur-
cates in the neck, and the two ventral tracts are single, and
there is no such abrupt break between the two parts of the
dorsal tract as has been described above in Steatornis. Nor is
there in Antrostornus, where there is no narrowing of the pos-
terior part of the dorsal tract. Nyctidromus is much the same.
The tongue in the goatsuckers is more or less abortive; in
Podargus it is a curious tough but transparent membranous
organ.
As mentioned in the definition of the group the cæca are
large; but as a unique exception Ægotheles seems to be
entirely without them. In all the genera the left lobe of the
liver is rather the smaller ; and all, savę Chordeiles, have a
gall bladder. The intestinal measurements in inches are
given on the following page.
The intestine (according to MITCHELL) is primitive and
owl-like, while the cæca are dilated apically, as in owls.
J. MURIE, ‘Fragmentary Notes on the Guacharo, or Oil Bird,' Ibis (3), iii. p. 81 ;
L'HERMINIER, "Mémoire sur le Guacharo,' Noriv. Ann. Mus. iii. 1834, p. 321,
and note 'Sur la Classification Méthodique du Guacharo,' &c., Rev. Mag. Zool.
(2), i. p. 321 ; J. MÜLLER, ' Ueber die Anatomie des Steatornis caripensis,' M.B.
k. Akad. Wiss. Berlin, 1841, p. 172, and · Anatomische Bemerkungen über den
Guacharo,' Arch. f. Anat. 2. Phys. 1842, p. 1.
For further details of feathering see CLARK, "The Pterylography of certain
American Goatsuckers and Owls, Proc. U. S. Nat. Mus. xvii. 551.
CAPRIMULGI
235
Cæca
1.3, 1.4
Nyctidromus albicollis , .
Caprimulgus europæus ..
Chonde
Chordeiles texensis
? . .
. .
Podargus Cuvieri . . .
Steatornis caripersis . .
.
.
.
.
:
.
.
S.I. L.I.
7.5 1.4
105
9.5
7
1.6
1.75
1.1, .9
16
.
. 18.5
-2.
1.25
-1.75
W
.
LT
.
311
27
1
E
w
ili
The syrinx is highly characteristic in the Caprimulgi.
Like the nearly related (?) cuckoos, we have both the
tracheo-bronchial and the purely bronchial syrinx. In-
deed, the stages are almost identical in the two groups.
Cuculus and Caprimulgus correspond with a tracheo-bronchial
syrinx; then we have Centropus and Podargus, and finally
the culmination in Crotophaga and
Steatorvis of a syrinx furnished with
a membrana tympaniformis, which
does not commence until many rings
below the bifurcation of the tube,
the intrinsic muscles being attached
to the first ring which borders upon
it. It will be necessary to describe
the various syringes in some detail;
they have been studied and figured
by myself.' In Nyctidromus albicol-
lis, which will serve as a type of the
tracheo-bronchial syrinx which ex- FIG. 113.-SYRINX OF Nycti-
ists in the Caprimulgidæ (s.s.), the
dronus albicollis (AFTER
sono
BEDDARD).
last four tracheal rings are closely
applied in contradistinction to the preceding, which are
separated by copious membranous intervals. The last two
tracheal and the first five bronchial semi-rings are ossified.
To the first of the latter are attached the intrinsic muscles.
In Batrachostomus we have the intermediate type of syrinx,
which may, however, be called bronchial. The first six
bronchial semi-rings and the last three tracheal are ossified,

IN
.PRO
T'On the Syrinx and other Points in the Anatomy of the Caprimulgidæ,'
P. Z. S. 1888, p. 147.
236
STRUCTURE AND CLASSIFICATION OF BIRDS
and bear much resemblance to each other, which will be
apparent from the illustration (fig. 115).
The intrinsic muscles are attached to the seventh bron-
chial ring, which is soft and cartilaginous; where the bronchial
rings change their character is a constriction of the mem-
brana tympaniformis ; it is, however, of equal breadth before
and after the change. In Podargus Cuvieri there is a further
approach to the purely bronchial syrinx of Steatornis. The


33SREDS
.
NO
ONAN
A
COZI
.....
.
IMININO
are
.
..
III
A ll
SMHIMU
I
::1:
www
Aw
.
.
utiles
.
7:Y
2
A2:
S
mation!
itindo
Fig. 114.-SYRINX OF Ægotheles
(AFTER BEDDARD).
FIG. 115.-SYRINX Or Batrachostomus
(AFTER BEDDARD).
first two bronchial rings are complete. These and the four-
teen following are closely applied to each other and ossified.
The intrinsic muscles are attached to the last of this series.
Ægotheles really belongs to this section of the Caprimulgi,
though the intrinsic muscles are attached very high up upon
the bronchi; but the two rings immediately preceding the
attachment are complete rings. The final development of
the bronchial syrinx is seen in Steatornis (see fig. 48, p. 69),
where all the rings in front of the attachment of the intrinsic
muscles low down upon the bronchi are closed and complete
rings, as in Crotophaga.
The tensor patagii shows certain differences among the
goatsuckers. In the genera Caprimulgus, Nyctidromus, and
Chordeiles there is a biceps slip, absent in the rest. Of
these three genera the arrangement of the tendon is shown
:
237
CAPRIMULGI ..
.
in the annexed cut (fig. 116): Steatornis, as will be seen
(fig. 117), hardly differs, and Podargus agrees with it. In
Ægotheles there is a slight difference in that there is hardly
any trace of the wristward branch of the tendon. Steatornis
has an expansor secundariorum, apparently absent among
the other genera. The muscle is attached to the teres by its
long tendon. The insertion of the deltoid is extensive, and
it receives a tendon from the scapula. · In many Caprimul-
gidæ the biceps is split for some distance before its insertion,
the bifidity even invading the muscle itself and not being

w
4
.
!
I
:
Opbell

.
ww
.
wp6
::
www.
.
www
*
w
.
.
.
.
.
AL
SU
w
WED
www
ce
.
2
DON
PA
.
++.
G
).
L-
,-
ecr
0
echo
IN!
IS
:
OS
BS
.
AN
.
RINO
..
A
.
Fig. 116. – PATAGIAL MUSCLES OF
Caprimulgus (AFTER GARROI)).
d, de toid ; 0, biceps; n, humerus; tpo, ten-
sor patagii brevis ; ecr, extensor carpi radialis.
FIG. 117.--CORRESPONDING MUSCLES
or Steatornis, BUT OF LEFT WING
(AFTER GARROD).
1, triceps. Other letters as in fig. 116.
IO
limited to.its tendon. In Podargus FÜRBRINGER describes
a special slip of rhomboideus profundus, arising separately
from ilium. The anconcus has a tendinous humeral head.
In the thigh the muscle formula is either AXY – (most Capri-
mulgi) or XY – (Steatornis). Thé. tibialis anticus tendon of
Podargus is double. The glutæus I. extends over biceps in
Nyctidromus, &c., not in Ægotheles. No glutæus V. There
are sometimes both and sometimes only one of the two
peroneals present. In Steatornis and Ægotheles only the
brevis is to be found, in Nyctidromus only the longus; in
Podargus both.
238
STRUCTURE AND CLASSIFICATION OF BIRDS
The goatsuckers have by no means a uniform skull
structure.
In Caprimulgus 1 the skull may be termed schizognathous.
The palatines are enormously expanded, and between their
posterior extremities (not indicated in the figure) are a small
anterior and posterior medio-palatine, a state of affairs recall-
ing the Picidæ (q.v.) The vmer is a long bone, distinctly
paired in the young bird, rounded in front. It articulates

Pmx
.
.
.
MIR
.
.
C
.
.
2
ZA
IA
MUS
TAL
Pn.
-
A
w
.
.
A
TWARZA
*.
TRAIN
CAS
AM
V
Co
RI
A
ABBIG
ASE
E-
16
Siz
TOIV
VON
!
d
..
her.
LE
.
A
..
.
AL
.
.
SK
WANAS
NIKE
TA
20
Fig. 118.—SKULL OF Caprimulgus (AFTER HUXLEY).
Pmz, premaxilla ; Mxp, maxillo-palatine ; Vo, vomer ; Pl, palatine; Pl, pterygoid.
-
with the hook-like maxillo-palatines. Each of the latter is
connected by a ligament with the internal forward process of
the palatine of its own side, the hinder part of which is
largely ossified. The basipterygoid processes are well de-
veloped. The lacrymal is large and binds upon the zygoma.'
The ectethmoids are attached to the broad outer flange of
the palatines by a cartilaginous prolongation.
I PARKER,' On the Structure and Development of the Bird's Skull,' Linn.
Th. (2), i.
CAPRIMULGI
239
In Chordeiles ? the skull is much upon the same plan,
but the maxillo-palatines meet in the middle line, and may
even become ankylosed.
The skull is thus desmognathous, in fact. In C. virgi-
nianus, however, the bones do not meet.
The skull of Nyctibius jamaicensis (see fig. 119), de-
scribed by HUXLEY, is not widely different from that of Capri-
mulgus. The ligaments which unite the inner angle of the

.
.

Umz
ht
W
:
.
.
21.is
il
BBXl
.
.
.
-.
29
.ll
36
S
C
.
at
Fig. 119.-FORE PART OF SKULL OF
Nyctibius jamaicensis (AFTER
HUXLEY).
*, prerrontal process. Other letters as in fig. 118.
Fig. 120.-SKULL OF Steatornis
(AFTER HUXLEY).
palatine to the maxillo-palatines are, however, completely
ossified
In Podargus 2 the skull is completely doubly desmo-
gnathous. The basipterygoid processes are quite rudimentary.
There are two small azygous vomers. The palatines have
coalesced in the middle line. The lacrymal is small, if not
absent.
The skull of Steatornis has been described, with figures,
I SHUFELDT, 'On the Osteology of the Trochilidæ, &c., P. Z. S. 1885,
p. 891.
? PARKER, loc. cit. p. 124 (with figs. on Pl. xxiii.)
240
STRUCTURE AND CLASSIFICATION OF BIRDS
by GARROD,' and more recently and more fully (also with
illustration) by PARKER.The skull is quite owl-like in
general aspect with its decurved beak, and in the equality
between greatest length and greatest breadth. The lacrymal
is very small and is ankylosed to the orbital wall. The
Y

Pmx
N
A
Us
.
trais
WAISY
MU
.
.
*
.
.
WA
CO
ICIOS
I
Fig. 121.-SKULL OF Podargus (AFTER HUXLEY). LETTERS
AS IN FIG. 118.
maxillo-palatines are completely fused across the middle
line, the skull being desmognathous. The palatines also in
their middle part meet across the middle line. The vomer
is divided into two parts, one lying behind the other. The
anterior part is small, like the posterior part; they both
measure 5.5 mm. The posterior vomer is probably the
equivalent of the medio-palatine of Caprimulgus and other
birds. The basipterygoid processes are well developed. The
1.On some points in the Anatomy of Steatornis,' P. Z. S. 1873, p. 526.
2 “On the Osteology of Steatornis caripensis,' ibid. 1889, p. 161,
CAPRIMULGI .
241
.
ectethmoids are continued on to the quadrato-jugal bar by a
distinct ossified os uncinatum, as in Todus, Scythrops,
Musophagidæ, Piaya cayana, Cariama, and Procellariidæ.
The relations between the procoracoid and the clavicle vary
somewhat. In Podargus the process is large and reaches

COM
UN
min
Fig. 122.-STERNUM
OF Caprimulgus
(AFTER SCLATER).
Fic. 123.–STERNUM OT
Podargus (AFTER
SCLATER).
Fig. 124.-STERNUM
or Nyctibius (AFTER
SCLATER).
the clavicle ; it is small and does not in Steatornis and
Caprimulgus.
The number of cervical vertebræ varies from thirteen
upon the fact that in Steatornis the atlas, instead of being,
as is the rule among birds presumably allied to it, perforated
below for the reception of the odontoid process, is merely
deeply notched for the same. In Steatornis the dorsal
vertebræ are. opisthocoelous, as among the parrots alone
among probable allies. It is the rule among the Caprimulgi
for four ribs to reach the sternum. The sternum itself is
one-notched on each side in Steatornis, &c. It has four
foramina in Ægotheles, and is doubly notched on each side
242
STRUCTURE AND CLASSIFICATION OF BIRDS
in Podargus. . The spina externa is developed and slightly
bifurcate in Steatornis. There is no spina interna.
In view of the considerable variation in structure ex-
hibited by the group, the following tabular statement may
be of use.

Thigh
Muscles
Giutaus
Caca
+ 1 Gall Bladder i
+ 1

Skull
Basipt. Pr.
Sternum
Powder
Dowiis
Carotids
Biceps Slip
Exn. Sec.
+ + + 11 Oil Glard
1
1 +
|
Syrinx
Podargus.
AXY
Desm.
2 notches
Bronch.
+
Not over
biceps
XY
AXY:
>
Sleatornis
gotheles
Batrachostomus
Nuctibius .
„Vuclidromus 1
+
+ + +
1 notch
2 for.
| 2 notches
11 + + 1
Schiz.
+
+
- AXY
Over biceps +1+
1 notch
Tracle-
Bronch.
»
Caprimulgus.
Chordeiles .12 +t'.-
antrostomus
-
1
+ + +
+ + +
il
AXY!
AXY
AXY !
»
u
+
ti-
+ + +
+ 1 of
9
»
+++
=
go
1 1
|
There can be little doubt, from a consideration of the
above table, of the naturalness of a family Caprimulgidæ to
include the last four genera. In these forms, in all of them,
the toes are aberrant in that the last has only four phalanges,
and further that the claw of the middle one is serrated.
It will be noticed from the table that the amount of
structural variation among the Caprimulgidæ (s.s.) is exceed-
ingly small, the only character, indeed, of those selected
which varies being the gall bladder, which is absent in
Chordeiles, and shows signs of commencing disappearance
by its small size in some of the others. We might, perhaps,
add the desmognathism of Chordeiles ; but this is obviously
but a slight exaggeration of the ægithognathous palate of
the others. The enormous length of the second primary of
Macrodipteryx and Cosmetorris is a variation which does not
appear to be of great importance from a classificatory point
of view. :
The remaining genera are by no means so uniform a
group as that which those that have been already considered
form. In all of them, however (so far as is known), the
biceps slip is absent, the glutæus primus is of limited extent,
See Blyth in Ibis, 1866, p. 357.
CAPRIMULGI
243
the skull' is desmognathous, the syrinx is bronchial (least
marked in Ægotheles), and the outer toe has five phalanges,
while the middle toe has no serration. This is a fair
assemblage of identical characters. It is usual for Steatornis
to be separated as a distinct family from the Podargidæ, as
has been done by GADOW. It differs from Podargus in
seven out of the thirteen characters made use of in the
above table. It is often supposed that the Guacharo: is
peculiar among goatsuckers by reason of its vegetable diet;
but NEWTON states in his · Dictionary of Birds' that the
Podargidæ also partly nourish themselves on fruit. More-
over Ægotheles, which is by universal, consent placed in the
immediate neighbourhood of Podargus, differs from that
genus in four out of the thirteen characters, and from Stea-
tornis in exactly the same number. It appears possible to
place all these genera in one family, which, on account of its
greater antiquity, has had time to vary more than the Capri-
mulgidæ. It is also among members of this family that the
greatest number of points of affinity to the owls is met with,
a further argument in favour of their basal position.
The relationship of the Caprimulgi to other groups is a
puzzle hard of solution. This is partly, perhaps, due to the
fact that the goatsuckers are probably a somewhat ancient
group. That they are an ancient group seems to be shown
by the considerable amount of specialisation of structure
which they exhibit, by the primitive character of the
intestinal folds—the cæca being at the same time well
developed-by the double carotids, and by their wide distri-
bution, with a restriction in range of some peculiar types,
such as Steatornis.
The remarkable series of modifications of the syrinx is
one of the most striking facts in the anatomy of the group.
They share this with the Cuculi, and, though to a less extent,
with the Striges. It is, indeed, with this latter group that
the goatsuckers seem to be most nearly allied. This con-
clusion, which is in harmony with much recent opinion, is
curious in view of the external likenesses' which bind
1 For instance, the 'ears' of certain Podargide and of Lyncornis. It is a
R 2
244
STRUCTURE AND CLASSIFICATION OF BIRDS
together the two groups of birds, likenesses which might
fairly be put down to similarity of habit. These superficial
resemblances are, however, enforced by more deep-lying
structural similarities. MITCHELL has found that of the
various groups which may be supposed reasonably to be
allied to the Caprimulgi the owls come nearest to them in
the primitive character of the gut, while the cæca, swollen
at the ends, are alike in both. The owls too are nearly the
only other Coraciiform birds besides the Caprimulgi which
have well-developed basipterygoid processes. The trogons,
it is true, possess them, but then they differ in many other
important particulars.
STRIGES
Definition.-Oil gland nude. Aquincubital. Both carotids present.
Cæca well developed, ending in a dilatation. Skull desmogna-
thous and holorhinal, with basipterygoid processes. No ambiens,
semitendinosus, accessory femoro-caudal, biceps slip, or expansor
secundariorum.
LU
.
The owls, formerly associated with the Accipitres and
termed 'Accipitres nocturnæ,' or 'Nyctharpages,' are now
generally placed by themselves away from the hawks and
in the neighbourhood of some of the birds comprised under
the term “picarian. The group itself is characterised by
a great uniformity of structure, and by the possession, so to
speak, of so many negative characters. The resemblances
to the hawks are really only in habits and in beak and claw.
These, however, will be dealt with more fully later.
The owls comprise a considerable number of genera, of
which Strix stands rather apart from the rest, having as
near neighbours the Eastern Photodilus? and the Madagas-
cu Heliodilus.3
curious coincidence that the term 'morepork’is applied to Podargus in Australia,
and in New Zealand to an owl, Spilogluur Norre-Zelandice (fide NEWTON, Dict.
of Birds, sub voce 'Morepork ').
Except Starix and Asio otus.
2 BEDDARI), · On Photodilus badius,' Ibis, 1890, p. 293.
3 MILNE-EDWARDS, Observations sur les Affinités Zoologiques,' &c., Nouv.
Arch. Mus. (2), i. 1978, and in Hist. Nat. de Madagascar. See also R. B. SHARPE,
• A Note on Heliodilus,' P. 2. S. 1879, p. 175.
STRIGES
245
CY
1
ILO
:. It is often given as a character of the owls (and as a bond
of union with Pandion) that there is no aftershaft. There
is, however, a small one in Strix. As a rule the oil gland
is nude, but NITZSCH gives as a constant character of Hybris.
(=Strix) the presence of two minute feathers upon the apex
of that gland; in Asio otus too there are two or three small
down feathers upon the apex of the oil gland—all of which
facts seem to indicate a comparatively recent loss of the
apical tuft so often found in birds.
The rectrices are invariably twelve in number, except in
Micropallas, where there are but ten. A singular external
character of the owls, carefully gone into by KAUP,2 concerns
the asymmetry of the ears; with this is sometimes corre-
lated an asymmetry of the skull in the region of the ear.3 !
The tensores patagii of the owls 4 are on the whole
simple. In none of them is there a biceps slip. Very rarely
is there a recurrent tendon uniting the insertion of the
brevis with the longus (patagial fan). This occurs, how-
ever, in Strix Novce Hollandice (? always), S. flammea
(occasionally), and S. pratincola (? always). Something of
the same kind is found in Syrnium aluco, where, however,
the connection is between the tendon of the longus,
just at its origin, and the inner of the two branches of the
brevis. In most owls (Bubo maculosus, Scops leucotis,
Pulsatrix torquata, Athene noctua, Strix, Syrnium nebic-
losum) the tensor brevis sends off a wristward slip not far
from insertion of main tendon ; the latter alone crosses the
fore arm to be inserted on to ulna.
In Scops Lempiji, S. Asio, Asio otus, Ketupa javanensis,
Otus vulgaris, Bubo ascalaphus, and Nyctea nivea, there is
an additional posterior brevis tendon, arising separately from
the muscle. This latter tendon sometimes in Otus vulgaris
is connected with the middle one.
21
UUU
2
YS
VV
21.
Fide CLARK, 'On the Pterylographiy of certain American Goatsuckers and
Owls,' Proc. U. S. Nat. Mus. xvii. p. 551.
? A monograph of the Strigidæ, Zool. Trans. iv.
3 Cf. COLLETT, 'On the Asymmetry of the Skull in Strix Tengmalmi,
P. 2. S. 1870, p. 739.
: D'ALTON, De Strigum Musculis Commentatio, Halis, 1837; HEUSINGER,
Arch. f. Phys. vii. 1922.
246
STRUCTURE AND CLASSIFICATION OF BIRDS
In Asio otus there is a fleshy slip from pectoral to
longus tendon, and a fibrous slip from humerus to patagial
muscle just at origin of innermost brevis tendon. In Scops
Lempiji there are muscular slips to both longus and brevis
from the pectoral, and a fibrous slip from the humerus to
the longus tendon just at its origin.
The humeral origin of the anconcus is always present.
There is never an expansor secundariorum, so far as
is known.
The pectoralis primus is not at all double.
The only one of the leg muscles used by GARROD in
classification that is present is the femoro-caudal, the
formula thus being A-. Glutæus. I. is absent, glutæus V.
small. In Ketupa javanensis, however, V. is absent and I. not
quite so. Only one peroneal muscle is present, which is
attached to head of metacarpal. The tendon of insertion of
the tibialis anticus is divided ; in Pulsatrix I found it to
be trifid at insertion, and even the muscle itself was divided
into two for a short distance.
The deep flexor tendons are of type I. In Ketupa
ceylonensis the two tendons blend a quarter of the way down
the tarso-metatarsus; though blended the fibres can be
recognised, and it may be seen that those of flexor hallucis
mainly supply digits I., II., a small part only to rest of com-
mon tendon.
-
-
-
-
-
-
-
.
Small Int.
Large Int.
Caca
Ins.
Ins.
20
Ins.
2-5
3.5
4.5
22 .
25
40
34.5
30.25
24
Asio otus
Syrnium aluco .
„ nebulosum
Bubo ignavus .
, virginianus .
, capensis ..
Ketupa javanensis
ceylonensis
Athene noctua
passerina .
Pulsatrix torquata
Speotyto cunicularia
Nyctea nivea .
Surnia funerea
Gymnoglaux nudipes.
2.25
3.5
2.8
1.75
3.5
3.8
3.5, 3.25
2.5
14
..
2.5
-...
15
42
-
-
-
-
.-
.
16.5
9.9
1.5
2.2
-
---
+
1.4
-------
.
---------
..
-
--:--
-
---
---
--
..
.
--
-
-
-
-
-
-
STRIGES
247
ra
www.
...
Z
271
111
1111
Hill
The colic cæca are always (fig. 125) dilated at the blind
end. The liver lobes are subequal, and the gall bladder
appears to be always present.
The skull of the owls 2 shows some differences in Strix
from the characters which distinguish the majority of the
group.
In Strix the skull is elongate, the proportions being in
Strix flammea 56 length : 36
breadth. In another species
(Strix sp. inc.) 62 : 37.5.
On the other hand in other
owls the differences between
breadth and length show gra-
dually progressive series, cul-
minating in Speotyto cunicu-
laria, in which the proportions
are nearly equal, viz. 38 : 37.
The skull of Strix further
differs from that of other owls
in the swollen character of
the prefrontal processes,
which are thin, almost paper-
like sheets of bone in other
owls. Theinterorbital septum
of Strix is thick, while in the
remaining genera it is reduced
to a thin dividing lamina, as is
the case with most birds. The
skull characters of the genus Fig. 125.—COLIC CÆCA or Photodilus
(AFTER BEDDARD).
Photodilus are to some extent
intermediate between Strix and the remaining genera of the
Striges. The interorbital septum of Photodilus is not
so thick as in Strix, but, on the other hand, not so thin as in
other owls, as, for example, Bubo. The prefrontals, although
not so swollen as in Strix, are not nearly so flattened as they

Absent in Speotyto.; cf. SHUFELDT, 'Notes on the Anatomy of Speotyto,
Journ. Morpr. iii. 1889, p. 122.
? See for certain details of skull structure PARKER, Linn. Trans. (2), i. p. 138.
248
STRUCTURE AND CLASSIFICATION OF BIRDS
are in Bubo, where, as already explained, they are thin
plates, hardly thicker than a piece of paper. · So far Photo-
dilus agrees with Strix ; but there are points in which the
skull of this aberrant owl is nearer to the bubonine section
of the order. It has not the occipital convexities which are
so striking a feature of the skull of Strix. Finally Photodilus
is strigine in the non-extension over the occcipital region of
the temporal fossæ, which do so extend in many of the
Bubonidæ. In Strix there is but one notch on either side
A

.
AUX
S
AVI
.
SY
NA
Voir
Nii
.
.
":
.
AX
7
.
.
.
TA
22
Y.
XIDE
Cola
*
*
.
KAS
IL
.
A
11.
1
Y
!
"
07
113
15
V2
.
M
.
it.
A
L2
25
1W
.
.
*
.
.
733
:
V.
ari.
..
.
n
n
.
.
.
A
2
.
.
2.
ws
*
KY
(52
.
L
.
NO
SSY
.
Czy
,
2
'Q
AKS
1.
RU
w
22
.
.
.
1
WN
PAC
>
ST
KY
w
Fig. 126.-SKULLS or Strix (LEFT-HAND FIGURE) AND Bubo.
(AFTER BEDDAKD).
E, prefrontal process ; W, maxillo-palatines.
of the sternum ; in other owls, including Photodilus, there
are two. The vomer of the owls is not large,' and behind it
there is a medio-palatine, at least occasionally present.
The lacrymals, like the maxillo-palatines, with which
they come into contact, are swollen and spongy. The
nostrils are often partly covered by ossified alinasals, and
there is a largely bony internasal septum.
..
'Said by SACFELDT to be absent in Speotyto.
STRIGES
249
: In the foot of Strix (see fig. 127) the first phalanx of digit
III. is much less than the second in length; in most other
owls (fig. 128) these two phalanges are small and sübequal ;
Photodilus is intermediate. The latter genus has the pecu-
liarity that the last digit has only four phalanges instead
of five, the two basal ones being fused.
The number of cervical vertebræ does not appear to vary.

w
SALSA
i
.
all
.
ren
NA
Fig. 127.—Right Foot or Strix (AFTER BEDDARD).
I have found fourteen in Strix, Photodilus, Ketupa, and
other genera which I have examined. In Bubo bengalensis
the ring of the atlas is incomplete above; the significance of
lost, owing to the fact that Cariama is similarly characterised.
The hæmapophyses' in Ketupa javanensis commence as
single processes on C11, and extend to D3; on C10 is ir
250
STRUCTURE AND CLASSIFICATION OF BIRDS
bifid hypapophysis, and on C9 the catapophyses nearly form
a canal. Posterior catapophyses begin on C12, whence they
gradually climb the hypapophyses. Bubo bengalensis is
much the same, save that there is not a bifid hæmapophysis

.
AY
.
.
.
DEN!
-
NE
....
-
-
-
-
..
...
.
.
-
JIH
2-
.
..
ver
Vi
1
WW
.
KO
w
ASE
www
--
1
FIG. 128.-Lert Foot or Bubo (AFTER BEDDARD).
on 10. In Strix the catapophyses on C9 are distant. Photo-
dilus is like Ketupa.
To the sternum, which is one-notched in Strix and two-
notched in other owls, five ribs are attached. Dr. COUES !
I key to N. American Birds.
STRIGES
251
has mentioned the existence among the Striges of a "scapula
accessoria. The coracoids are not in contact at their articu-
lation with sternum; the procoracoids are moderately large,
and the clavicle reaches both them and the scapula.
If it were not for Photodilus, it might be possible to
divide the Striges into two families, Strigida and Bubonidæ.
As it is, it may perhaps be permissible to regard the order as
containing but one family, but two sub-families, viz. Striginæ

SE

=
=
Y
SA
3.3
SEXY
BRO
tu
.
ER
TA
.
.
TIS
S
ve
X
YUWAE
- RSS
ACT
.
MUVIN
ANNA
Tim
ES
**
bahan
7
SAHAYU
YAUTO2207
CITATION
Fig. 129.-SYRINX OF Scops lericolis
(AFTER BEDDARD).
Fia. 130.-SYRINX OF Bubo
(AFTER BEDDARD).
and Buboninæ, to which possibly a third, Photodilinæ, might
be added.
The syrinx of the Striges has been chiefly described by
WUNDERLICH' and by myself. This group is one of the
few that present the remarkable variety of the voice organ
which has been terined the bronchial syrinx. All the owls,
so far as they have been examined, possess one pair of
intrinsic muscles and the usual one pair of extrinsic muscles.
Scops leucotis has the most modified syrinx. In this bird
(see fig. 129) the intrinsic muscles are attached so far down
the bronchus as to the tenth bronchial ring, and, as will be
1' Beiträge zur vergleichenden Anatomie und Entwicklungsgeschichte des
unteren Kehlkopfes der Vögel,' Nov. Act. Leop. Akad. xlviii. 1884, p. 1.
2On the Classification of the Striges,' Ibis (5), vi. p. 355.
252
STRUCTURE AND CLASSIFICATION OF BIRDS
.
seen from the figure, the bronchial rings in front of this
attachment are complete rings, with no membranous inter-
space left. In Strix, on the other hand, and in Bubo and
Syrnium, the intrinsic muscles are inserted on to the first
bronchial semi-ring. In Asio seven complete rings intervene
between the bifurcation of the trachea and the first incom-
plete bronchial semi-ring, to which the muscles are attached.
In Photodilus the intrinsic muscles are inserted on to the
second bronchial semi-ring.
Until lately the owls have been almost invariably placed
in the immediate neighbourhood of the diurnal birds of prey.
Latterly, however, the opinion has been gaining ground that
it is to the picarian birds (in a wide sense) that they are most
nearly allied. This opinion, more than hinted at by GARROD
and NEWTON, has been given a practical shape in the classi-
fications of FÜRBRINGER and GADOW. The latter has in-
geniously pointed out that it is impossible to imagine that
the Striges have been derived from the Accipitres, since,
although without an ambiens, they have much the same
structure of foot as the Accipitres with an ambiens. Hence
it is difficult to believe that they would have lost it; he con-
cludes that they are derived from some bird without an
ambiens, and the failure of MITCHELL to find the last trace
of the missing ambiens-obvious in some birds which are
clearly. the descendants of birds with an ambiens-still
further supports that way of looking at the matter. Even
in the skull, where the principal likenesses between the
Accipitres diurnæ and nocturnæ (as the two groups in
question have been called) have been seen, there are really
many differences. It is only, for example, in the skulls of
those Accipitres to which the owls have been supposed to
have the least resemblance, i.e. the Cathartidæ and Serpen-
tariidæ, that there are basipterygoid processes. The owls
are decidedly not desmognathous (in the sense of a maxillo-
palatine union), and their lacrymal is quite different from
that of the hawks and eagles. The palate, too, is incom-
plete in front of the maxillo-palatines, not solid, as in the
Accipitres. As to other anatomical features, it is harder to
STRIGES
253
find likėnesses than differences. The Accipitres have rudi-
mentary cæca, a biceps slip, the expansor secundariorum, a
tufted oil gland, an aftershaft (except Pandion); the deep
flexor tendons are different, and, in short, the differences are
as great as those which separate any two groups of carinate
birds.
11
PSITTACI
Definition.—Twelve rectrices ;? aftershaft present; aquintocubi-
tal; żygodactyle. Skull desmognathous, holorhinal, with-
out basipterygoid processes. Biceps slip and expansor se-
cundariorum absent. Muscle formula, AXY + or -. No
cæca ; a crop present.
The parrots are an almost cosmopolitan group, being
most abundant, however, in the tropics. Count SALVADORI,
in his British Museum catalogue of the group, allows five
hundred species, distributed among seventy-nine genera.
The parrots are a very sharply defined group, there being
no dubious outlying forms. They are usually brilliantly
coloured, and lay white eggs in hollows of trees. With the
exception of the owl parrakeet (Stringops) of New Zealand
the parrots are arboreal birds, as, indeed, the zygodactyle feet
denote. As to external characters, the exaggeratedly hawk-
like bill is well known. The almost universal twelve
rectrices distinguish the group, but in other external and
internal characters the parrots show considerable diversity
of structure, as is sometimes the case with large and widely
distributed groups ; compare, for instance, the pigeons, which
present many other analogies to the parrots.
The oil gland 4 is a structure which may be wanting or
developed. The table on p. 268 indicates some of the genera
See also under · Çaprimulgi,' p. 243.
2 With the sole exception (cf. GADOW) of Oreopsittacus Arfaki.
.: 33 See below, p. 261. .. .
- External characters and many other points in the anatomy of parrots are
dealt with by GARROD;." On some points in the Anatomy of the Parrots,' &c.,
P.Z.'s. 1874, p. 247, and Notes on the Anatomy of certain Parrots,' ibid.
1876, 1. 691 ; see also FORBES, 'On the Systematic Position of the Genus
Lathamus, ibid. 1879, p. 166. .
25+
STRUCTURE AND CLASSIFICATION OF BIRDS
1
.
in which it is present or absent. When present it is in-
variably tufted, and generally of fair size. In Cacatua sul-
phurea, however, the oil gland, though present, is small, and
has but a single small down feather upon it.
The parrots are a group of birds which agree with the
Accipitres in that some genera have powder-down patches
while others have not. The table already referred to indi-
cates the facts so far as they have been ascertained. The
degree of development of the powder-downs, however, differs
considerably, though in no parrot is there more than a single
pair of definite powder-downs which are lumbar in position.
In Cacatua sulphurea, for instance, there are a pair of such
patches, one on either side of the dorsal tract. These send
up a few scattered powder-down feathers as far forward as
the neck, and a few to carinal spaces and between the
branches of the ventral tract.
In Calopsitta Novæ Hollandiæ there are the same lumbar
patches of a reniform outline; but the powder-downs are
entirely confined to this region of the body.
Calyptorhynchus stellatus is more like Cacatua, but the
lumbar patch is not so well developed.
In Psittacula passerina there are lumbar patches more
elongated but narrower than those of the parrots already
referred to; there are also scattered powder-downs not
aggregated into patches.
Brotogerys tirica has no defined. patches, but simply a
few scattered powder-downs, which, however, are more nume-
rous in the lumbar regions. In Coracopsis, Chrysotis, and
Pionus there are the same generally diffused powder-down
feathers not aggregated into definite tracts. The same may
be said generally of Psittacus, though such powder-downs as
there are are limited to the lumbar region.
The general pterylosis of the parrots is as follows: From
the general covering of the head arises a narrow dorsal tract,
which bifurcates in the interscapular region. Between the
arms of this fork are the arms of another fork, which unite
near the oil gland to form the single straight, short posterior
part of the dorsal tract. On the ventral surface the tract is
PSITTACI
255
21
single, or double on the neck, and where it widens out on
either side of the carina sterni a strongly feathered lateral
branch is given off.
The variations shown in the pterylosis are not great.
They concern the more or less definite separation of the
lateral ventral tract and the slighter or more pronounced fea-
thering of the anterior end of the posterior dorsal Y. Thus
in Lathamus and Platycercus the lateral ventral tracts are
well marked, and the posterior fork of the dorsal tract does
not diminish much in width where it comes into contact
with the anterior fork. In Trichoglossus the exact reverse
of these conditions obtains, the lateral ventral tracts being but
obscurely delimited from the main tract, and the dorsal tracts
of the hinder part of the body almost ceasing before their
junction with the anterior half. ,
Psephotus, Cyanorhamphus, Pyrrhulopsis, Agapornis, &c.,
agree with Platycercus. In Ara the outer branch of the
pectoral tract is not definitely separable, but the dorsal tracts
are more like those of Platycercus. Conurus is much the
same.
The syrinx of the Psittacil seems to show two main
varieties.
a. In the following species there is a syrinx of the type
which will be described immediately :-
Cacatua cristata.
,, triton.
, Philippinarum.
Microglossa aterrima.
Calyptorhynchus Banksi.
Stringops habroptilus.
The syrinx is in these species remarkable for the fact that-
the first semi-rings of the bronchi are weak and cartilaginous,
and are usually separated from each other by considerable
tracts of membrane. Cacatua itself represents the most ex-
LU
TY
? The syrinx has been chiefly studied by GIEBEL, · Zur Anatomie der
Papageien,' Zeitschr. f. d. ges. Wiss. xix. p. 133, and by PARSONS and myself,
On certain Points in the Anatomy of Parrots,' &c., P. Z. S. 1893, p. 507.
256
STRUCTURE AND CLASSIFICATION OF BIRDS
treme type; in Cacatua cristata, for example, when the syrinx
is seen on a lateral view the membrane occupies a great deal
of the outer lateral region of the commencement of the
bronchus.
The semi-rings of the bronchus are at first very small, and
do not extend across the side of the bronchus; they gradu-
ally increase in length, until at the sixth or seventh they
come to extend right across the syrinx. In Microglossa
aterrima the syrinx is in certain respects less abnormal ;
the rings are still feeble, but on a lateral view of the organ
they extend completely across, and there is on such a
view no bare tract of membrane, such as we have figured
in Cacatua.
Calyptorhynchus Banksi is intermediate between the
two extremes ; the first semi-ring only is incomplete, inas-
much as it does not reach from one side of the syrinx to
the other—or rather we should say from the anterior to the
posterior side.
Stringops habi'optilus. has the same weak cartilaginous
bronchial semi-rings; but on a lateral view of the syrinx they
are seen to extend right across.
6. The second group contains the following genera :-
TV
Chrysotis.
Pyrrhulopsis.
Trichoglossus.
Lorius.
Pionus.
Psittacus.
Tanygnathus.
Eos.
Polyteles.
Platycercus.
Pæocephalus.
These genera' are differentiated from those of the first
division by the fact that the bronchial semi-rings are as a rule
ossified, and are frequently more or less fused together; åt
the same time the first ring is commonly concave upwards,
whereas in the parrots of the first-mentioned group the
bronchial semi-rings are straight.
The most extreme' type is perhaps offered by `Chrysotis; .
of this genus I have seen the following species :-
PSITTACI
257
.
Chrysotis versicolor".
, erythrura.
leucocephala.
Chrysotis Bodin.
į viridigenalis.
» Levaillanti.
In all these species the first two rings of the bronchus
are closely fused together, and form a bowed piece of bone
forming with the last tracheal ring a semicircular outline; the
space between the two is, of course, occupied by membrane.
In Chrysotis Levaillanti, for instance—and there is no great
difference in the other species--the double character of the
apparently single first bronchial semi-ring is only to be seen
at the two ends. In a number of other parrots the first
bronchial semi-ring is larger than that which follows, though
not fused with it; this is the case with Trichoglossus,
Pyrrhulopsis, and Chalcopsitta; the genera Eos, Polyteles,
Platycercus, and Tanygnathus have syringes which are con-
structed on the same plan.' In Conurus there is a little
difference; here the first two rings of the bronchus are equi-
sized; this at any rate applies to the two species Conurus
aureus and Conurus cruentatus, which are the only two that
we have examined from this point of view. The genus Ara
(species Ara Leari, Ara militaris) agrees with Conurus.
Psittacus is like these genera ; but Pionus agrees more closely
with Chrysotis.
It will be obvious that no hard and fast line can really
be drawn between the two groups of parrots; if it were
thought desirable to draw such a line, it would be between
the genus Cacatua on the one hand and all the remaining
parrots on the other. . Cacatua alone has a syrinx in which
the first bronchial semi-rings are incomplete, leaving a bare
tract laterally which is easily visible when the syrinx is
viewed from the side: but in this genus there is another
peculiarity--the intrinsic muscle of the syrinx ends in a very
narrow point, which passes into a fine tendon of attachment;
in Chrysotis, Eos, &c., the muscle is comparatively broad
down to its actual attachment. In this particular Micro-
glossa and Stringops agree with Cacatua, although they do
not show the incomplete rings that have been mentioned as.
Inn
258
STRUCTURE AND CLASSIFICATION OF BIRDS
11
.no
characteristic of the latter genus. These genera, in fact, are
to this extent intermediate between Cacatua and the more
normal (at any rate more usual) form of syrinx in the
parrots; the rings are still, however, soft and cartilaginous,
thus different from Conurus, which is a further step in the
direction of Chrysotis ; Chrysotis seems to represent the
opposite extreme to Cacatua. Ara is a genus which is
also intermediate in the characters of its syrinx; it has
weakish and straight rings, as in String ops, for instance ;
but the muscles are as in the second group of parrots, and
the general aspect of the syrinx is more in accord with this
placing of it.
Finally it should be added that occasionally (e.g. Polyteles
melanurus) the extrinsic muscles are attached not to the
sternum, but to the membrane covering the lungs, being con-
tinued there by thin tendons. In Platycercus Barnardi
there would seem to be no extrinsic muscles at all.
Parrots are very much alike in their myology; there are,
however, a few points in which they show differences, and
which may be useful for the purposes of classification.
The tensores patagii of the parrots are like those of
many homalogonatous birds in the broad aponeurotic
character of the tendon of the tensor brevis, which, however,
has two or three thickened bands in it corresponding to the
discrete tendons of most other birds (e.g. Charadriidæ). Of
these thickened bands the anterior commonly gives off a
wristward slip; but there appears to be never any patagial
fan. The aponeurosis is inserted, as usual, on to the tendon
of the extensor metacarpi radialis, and is continued over it
by two tendinous slips, of which the posterior runs obliquely
to the elbow joint, like the 'passerine slip' of many birds.
The common tensor patagii muscle is usually very large, and
often completely covers the posterior deltoid (d. major).
GARROD dissected away the anterior thickened tendon of the
brevis in Deroptyus accipitrinus, and found it to arise from
a distinctly separate slip of the patagial muscle attached to
clavicle. The tendon in question is inserted on to the lower
external humeral process, and may represent with its muscle
12
LU
PSITTACI
259
a primitive passerine tensor patagii brevis, to which has
been subsequently added an extension of the deltoid.
With the general structure that has been described the
parrots show much difference in the details of the patagial
tendons.
The arrangement of the tendons of the tensor patagii is
very much the same in Nestor, Stringops, and Calypto-
rhynchus ; in all three the tendons are relatively very long
when compared with the fleshy part of the muscle, and they
are all close to one another, so as to give the appearance in
Stringops of one tendon. In Calyptorhynchus the anterior
tendon leaves the others in the lower part of the patagium
and runs forwards after its usual fashion, so that the main
distinctive point of these three genera, as far as the tensor
patagii goes, is that the middle and posterior tendons are
close together. In Coracopsis these tendons are separated
by a slight interval, bnt closely correspond to the arrange-
ment in the birds last named.
Eos, Lorius, Pæocephalus, and Caica have a character-
istic and almost uniform arrangement of the patagial tendons.
In them the three tendons are very difficult to distinguish,
because the fibrous membrane between them, of which they
are only specialised parts, is as thick as they are. The result
is that in these birds the patagial muscle seems to be inserted
by a broad, short, membranous-looking tendon.
Conurus shows a transitional stage between these last
genera and the typical arrangement; the three tendons are
more distinct, and they are equally short and show the same
mode of attachment to the fleshy part of the muscle.
Lathamus is remarkable for having the anterior tendon
separate in its whole length from the middle one, instead of
being fused with it in the upper part of its course.
Chrysotis and Bolborhynchus have a small extra tendon
between the middle and posterior ones; in C. Guildingi this
was only present on one side, but in C. leucocephalu it was
found on both.
Psittacus has three tendons which are completely separate
in the whole of their course, and in this respect it corre-
12
s 2
260
STRUCTURE AND CLASSIFICATION OF BIRDS
VA
sponds to Lathamus. The anterior tendon may represent the
fused anterior and middle tendons of Lathamus, and the
middle tendon may be an extra one, as in Chrysotis. Our
reasons for this are that there is a considerable interval
between the two tendons, and that they do not diverge, as
in all other cases. If this view is correct, the patagial
tendons of Psittacus closely resemble those of Chrysotis;
while they also agree in having the anterior deltoid larger
than the posterior, in the absence of a lower head to the
anconæus, and in having the deltoid completely covered by
the tensor patagii.
The two deltoids are but small muscles, and are largely
covered by the relatively enormous tensor patagii. It is
better to use the terms 'anterior’and posterior’ for the del-
toids, since their relative dimensions vary considerably. The
major is by no means always the larger. Sometimes the
two deltoids are entirely covered by the tensor patagii, some-
times the posterior is partly exposed. Thus in Nestor the
muscle is exposed, in Deroptyus and Chrysotis it is covered.
In Nestor and Stringops the anterior deltoid is the smaller,
in Caica it is the larger. In Tanygnathus, Bolborhynchus,
and Eclectus the deltoids are narrow and equisized. In Eos
cardinalis the anterior deltoid (which is the larger) is di-
visible into two distinct parts.
As regards the relative sizes of the two deltoid muscles,
where they differ, such genera as are known may be arranged
as follows:
>
2
TA
A. Delt. Larger
Post. Delt. Iarger
Deroptyus, Psittacula, Aprosinic:: Nestor, Stringops, Calyptorhynchus,
tus, Lorius, Caisa, Eos, Pyrrhulopsis, i Cacatua.
Lathamus, Palæornis, Loriculus,
Psephotus, Pæocephalus, Cyano-
rhamphus, Psittacus, Melopsittacus.
GU
In some parrots the anconcus longus has an accessory
head from the humerus, which is especially broad in Stringops
The table on p. 268 shows the distribution of this accessory
head among the genera.
The expansor secundariorum is stated by GARROD to be.
PSITTACI
261
absent from the Psittaci. This is certainly almost univer-
sally the case. But FÜRBRINGER speaks of a rudiment-a
short length of tendon—in Platycercus palliceps.
No parrot has a biceps slip. A muscular cucullaris
patagialis is generally, if not always, present.
It is well known that the ambiens muscle is present in
some parrots, and absent from the leg of others. The actual
occurrences of this muscle are shown in table (p. 268). Strin-
gops is peculiar in that the muscle is sometimes complete
and quite normally developed, and sometimes ends in a thin
tendon on the capsule of the knee joint. This recalls
Edicnemus.
Of the other muscles of the leg used by GARROD in classi-
fication A, X, and Y are nearly always present, the only
exception, so far as I am aware, being Chrysotis Guildingi, in
a specimen of which I failed to find Y.
Sometimes (as. in Ara chloroptera) the semitendinosus
gives off a tendinous slip to the gastrocnemius, but in
Chrysotis there is no such slip. The tibialis anticus is
usually inserted by a single tendon. This Mr. PARSONS and
I found to be the case in the majority of parrots which we
examined. But in Chrysotis the tendon is distinctly double.
In Deroptyus, Caica, Pæocephalus, Platycercus, and a few
others, there are more or less evident indications of a double
tendon.
The deep flexor tendons of the parrots are gallinaceous,
with a vinculum such as is illustrated in fig. 54 (p. 100).
There are some inconsiderable variations of this ground plan;
for instance, in Platycercus Barnardi the vinculum is divided
into two parts, one to digit II., the other to III. and IV.
Peroneals.—The peroneus longus and brevis are, as far as
we have observed, always present in parrots, but the origin.
of the former differs somewhat in different genera.
In Stringops and Nestor the peroneus longus rises from
the front of the bony fibula and its membranous continuation
for about the upper half of the leg. The muscular belly
overlaps that of the peroneus brevis very much near its
origin, and the muscle is large and well marked.
LUCU
262
STRUCTURE AND CLASSIFICATION OF BIRDS
In Chrysotis, on the other hand, the peroneus longus is
very small and only rises from the membranous continua-
tion of the fibula in the lower part of the leg; it is so small
that it does not overlap the peroneus brevis at all, but lies
behind it.
The parrots have a well-developed crop and a zonary
proventriculus. In the liver the right lobe is the larger ;
rarely are they subequal. The gall bladder is as a rule
absent; but it is present in Cacatua and in Calopsitta, though
'small and easily overlooked' in the latter.
The intestinal measurements in a series are as follows :-
Inches.
Inclics.
.
.
w
27
Stringops . . . 73 - Tanygnathus Mulleri 57
Eclectus polychlorus . 93 Psittacus erithacus. 48
Calyptorhynchus
Conurus Petzii. . 12
Banksi . . . 61 Palæornis Alexandri 30
Ara ambigua . . 62 Aprosmictus erythro-
» Ararauna . 50 pterus . . . 41.
Cacatua sulfurea : 33.75 Lorius lori . . 33
u cristatai
37 Loriculus chrysonotus 12
, triton . . 51 o galgulus. 16
Pionus senilis . . 50:5 Chalcopsitta scintillata 37
, Maximiliani 49 Psittinus malaccensis 12
Eos reticulata . 255 Euphema pulchella . 12
, indica . . 26
, splendida . 12
Platycercus Barnardi 29.5 : Deroptyus accipitrinus 31
, pallidiceps 20 . Pionopsitta pileata. 39
Nestor meridionalis 38 Lathamus discolor. 18
Microglossa aterrima 34 . Coracopsis Barkleyi. 33
Pyrrhulopsis splendens 43 Dasyptilus Pecqueti. 17-25
Chrysotis collaria . 45 Brotogerys tirica 31
festiva. . 36
u tovi. . 21
Geopsittacus occiden-
talis . . . 15
..
..
..
..
-.
The most obvious comment upon the above list is to
draw attention to the very great length of the gut in Eclectus,
PSITTACI
263
0222
UUUUU
Inn
11
ULV
whose relations in this particular to other parrots are almost
those of Didunculus to other pigeons.?
The most recent and elaborate essay upon the osteology
of the parrots is by MIVART,2 who has described the entire
skeleton of Lorius and Psittacus; some of his illustrations
are reproduced here. Fourteen is the prevalent number of
cervical vertebrce (e.g. Lorius, Psittacus, Platycercus, Caica).
Stringops, however, has fifteen. The atlas is notched (Ara
militaris) or perforated (Pyrrhulopsis). for the odontoid
process. Five (Ara, Psittacus) or six (Platycercus, Pyrrhu-
lopsis) ribs articulate with the sternum. The sternum has
as a rule an entire posterior margin, which in Licmetis is
entirely unnotched and unfenestrated. Most parrots have a
pair of fenestræ which in Deroptyus and Microglossa are
converted into notches. The sternum has a spina externa,
slightly forked occasionally (e.g. Psittacus erithacus, Callo-
cephalon), but no spina interna. The carina is deep-deeper
in Platycercus (without furcula) than in Caica (with furcula),
the species being approximately of the same size. The
furcula is sometimes present and sometimes rudimentary.
It is present, and forms a complete U, in Nestor, Conurus,
Caica, Licmetis, Microglossa, Ara, Palæornis, &c.
An intermediate condition is observable in Eos, where the
furcula thins much towards its sternal end. A still further
reduction is seen where the two clavicles are separate below
and only bound by cartilage. Finally there are those parrots
with a quite rudimentary pair of clavicles, consisting only of
a small piece of bone at the coraco-scapular end. This is the
case, for example, with Pyrrhulopsis and Platycercus.
The following table shows the number of cervical verte-
bræ and the position of the first and last hæmophyses in a
number of parrots :-
TU
VIU
LCU
For structure of tongue see Ciaccio, Nota preventiva sull'interna.
struttura della lingua dei Papagalli,' Rendic. Sess. Acc. Ist. Bologna, 1877-8,
p. 157.
?• The skeleton of Lorius flavopalliatus compared with that of Psittacus:
Crithacus,' P. Z. S. 1895. There is no account of the bones of the limbs.,
264
STRUCTURE AND CLASSIFICATION OF BIRDS
No. of
C. V.
First
Eæm.
). ast
Heu.
Catap.
ܥܛ
C9 / 13
ܠܛ
ܠܛܙ ܠ
D2
D1
D3
ܠ
Pyrrhulopsis personata
Conurus hæmorrhous .
Platycercus Penianti .
Ara militaris . .
Eclectus polychloros.
Nestor notabilis.
Caica melanocephala .
Callocephalon galeatum
Calopsitta Nove Hollandic
Conurus cruentatus . .
C13-D1
C14
C12-14
C13-D1
C11-DI'
C12-D1
C13-01
C13-14
C12-14
C12-13
ܠܛ
ܟܢ
ܠܣܛ
ܠܛܙ
D2
The humerus of parrots is peculiar, and, as GARROD 3 has
pointed out, there are features of resemblance to the Columbæ
and to the Alcidæ. This peculiarity will be found described
and figured in the chapter dealing with the Columbæ. The
skull is very uniform in its structure throughout the group.
It is desmognathous, holorhinal, and without basipterygoid
processes.
The front part of the face (nasals, maxillæ, and premaxillæ)
articulates by a transverse joint with the frontals, which is
movable. The mobility of the anterior part of the face is
aided by the movable articulation to it of the palatines and
the jugals. The palatines have a peculiar form; for the
most part they are laterally flattened plates of great depth
and considerable extent. The quadrate of parrots too is
peculiar in the great length of the neck, which bears the
squamosal articulation. In many parrots the lacrymal bone
joins the forward process of the squamosal, thus completely
encircling the orbit with bone.
The hyoid has been extensively studied by MIVART; 4 in
On D1 the median part of the hæmapophysis has vanished, leaving only
the lateral.
2 On this vertebra is a double hæmapophysis, forming a canal.
3. See also for osteology of parrots BLANCHARD, 'Des Caractères Ostéologiques
chez les Oiseaux de la Famille des Psittacides,' Compt. Rend. xliii. p. 1097,
and xlix. p. 518 ; MILNE-EDWARDS, Observations sur les Caractères Ostéolo-
giques,' &c., Ann. Sci. Nat. (6), vi. p. 91 ; L. VON LORENZ, · Über die Skeleto
von Stringops habrop tilus u. Nestor notabilis,' S.B. k. Al. Wien, lxxxiv. 1882,
p. 624.
4.On the Hyoid Bone of certain Parrots,' P. 2. S. 1895, p. 162.
PSITTACI
265
this paper references will be found to previous figures and
descriptions. It has features which absolutely distinguish
this group of birds.
The entoglossal has a considerable median foramen, or


A
.
.
WC
..
DI
Vn
ho
cbm
-CB

NY
SV
1.
CZ
VINE
a
Fig. 131.—HYOID OF Stringops (AFTER MIVART). A. DORSAL ASPECT..
B. VENTRAL. C. LATERAL.
o, basihyal : C, entoglossum ; , paraliyal jirocess ; u, uroliyal ; hi, hypobranchial;
cb, ceratobranchial.
more usually is composed of two separate pieces united in front
by cartilage. The basihyal is broad, and it develops on either
side a forwardly directed piece (figs. 131-3), for which Dr.
MIVART has suggested the name of parahyal piece. This
266
STRUCTURE AND CLASSIFICATION OF BIRDS
latter is merely a short process in Ara, Psittacus, and
Stringops (fig. 131); in Lorius, Eos, and Trichoglossus the two
parahyals (figs. 132, 133) unite and form a single Y-shaped


with
.
V
no -
-hb
Wood
F
.

ha
'.
0
KO
SI
Fig. 132.-HYOID OF Lorius flavopalliatus (AFTER MIVART).
A. DORSAL ASPECT. B. VENTRAL. C. LATERAL.
c, cup-like excavation ; li, symphyses of parahyals. Other letters as in fig. 131.
bone inclined obliquely upwards. The only bird which
seems to present much resemblance to the parrots is the
eagle, which, according to the figure in BRONN'S Thierreich,''
Ares, Pl. xxxi. fig. 23.
PSITTACI
267
has a broad basihyal with the short angular processes which
suggest the more elaborate parahyals of the parrots.
The classification of the parrots has been attempted by
more than one naturalist; but, as GADOW has justly ob-
served, our knowledge of the anatomical structure of these
birds is at present too incomplete in relation to their large
numbers.'
Gadow himself has practically divided them by the
structure of the tongue into two families, Trichoglossidæ and
Psittacidæ. In all the Trichoglossidæ the orbital ring is

je
VI
tho
ce
Fig. 133.—HYOID OF Lorius domicella (AFTER MIVART). LETTERS
AS IN FIG. 131.
incomplete, and it is possible that the remarkable structure
of the hyoid, described above, may serve to distinguish this
family. The first family contains only Nestor, the lories,
Cyclopsittacus, and Lathamus; but the two latter are very
imperfectly known. The remaining genera are relegated to
the second family.
GARROD's arrangement of the group, anterior to that of
GADOW’s in point of time, is based upon the variations of
the ambiens, oil gland, furcula, and carotids. The facts,
with a few others added, are displayed in the following
table :-
268
STRUCTURE AND CLASSIFICATION OF BIRDS
Oil Gland
Ambieus
Carotids
, Humeral Head
1 + of Anconæus
Distribution
Furcula
---
-
-
-
--
-
-
-
-
--
-
-.-.
.
--
Stringops.
Palæornis .
.
..
+ + :
1
1 8 1
00
+
,
-
-
----
--
--
Aprosmictus
+
1
1
+
-
-
-
..
.
Polyteles
-
+
-
1 1
+- + f
1
Eclectus .
Tanygnathus
-
.
.
00
-
+ +
-
-
-
-. -. .-
-
-
-
Prioniturus
+ +
1 1
00
+ +
Eos
1
Trichoglossus
.
.
+
10
+
Lorius
+
M
+
1
Loriculuis.
Coriphilus .
Chalcopsitta
Psittinus .
OLON
+ + +
+
I
I
101010 ON
+ II
Agapornis'.
Euphema .
Melopsittacus
Geopsittacus
Eolophus. .
Calyptorhynchus
Calopsitta.
Licmetis
Microglossa
Cacatua .
New Zealand
Africa, India, China,
East Indies
Australia, Austro-
Malaya
Australia
Moluccas, Papua
Philippines, Celebes,
New Guinea
Philippines to Celebes
Moluccas, Papua, Solo.
mon Islands
Australia, Celebes,
Papua, Timor, New
Caledonia
| Moluccas to Solomon
Islands
India to Papua
Society and Marquesas
Papua
Malay Peninsula to
Borneo
Ethiopian region
Australia and Tas-
mania
South Australia
South Australia
+ | Australia to Philip-
pines
Australia
Australia
Australia
Papua, North Australia
i Australia, .Austro-
Malay, Philippines
Australia
Tropical Africa
Tropical Africa
New Zealand
New Guinea
Mexico to South
Arnerica
+ : Mexico to Soutb
America
+ Mexico to South
America
+ ! Guiana and Amazons
+ Costa Rica, South
! America
+ Guiana, North-East
Brazil
+ ot + +
+ +
+ + +
+ I +++ I II III III II IIII
+ + +
+
+ + + + + +
+
+
------------- ---- -----
+
+
+
1 +
+
+
o v 0101010
+ + + + +
+
Callocephalon
Psittacus .
Pæocephalus
Nestor
Nasiterna!.
Ara . .
11 +
+ + + +
.
+
+
n
Conurus
.
.
1
-
Bolborhynchus .
.
a
--
1
-
-
-
1
.
-
--
Caica .
Pyrrhula .
Deroptyus.
og or
-
.
+
1
1
FORBES, 'On some Points in the Structure of Nasiterna,' &c., P. 2. S. 1880, p. 76.
PSITTACI
269

Oil Gland
Ambiens
| Humeral Head
1 1 of Anconens
Carotids
Distribution
Furcula
-----
--------
---
--
..
--
.
------
+
Pionopsitta
.
+
Lathamus.
+
1
.
+
*
*
+ 1
+
+
Coracopsis .
Pyrrhulopsis
Dasyptilus .
Chrysotis .
1 + + +
.
.
-
.
+ + + +
- ..
+
1
00 00 00 00 00 00 00
- -
.
.
Piorus
1
1
.
1
Central and South
i America
Australia and Tas-
mania
Madagascar
Fiji
New Guinea
Mexico to South
America
Mexico to South
America
| Central to South
į America
Australia, Tasmania,
Norfolk Island
Australia
New Zealand, New
Caledonia, Society
Islands
Mexico to South
America
New Caledonia to
Loyalty Islands
+
+
1
-
Brotogerys . .
Platycercus .
Psephotus.
Cyanorhanphus .
-
.
.
-
I II
--
.
+ +
1 1
Psittacula .
1
.
00
+
.
1
Nymphicus .
+
2
.
+
From these facts and a few others may be derived the
following scheme :-
Sub-Order Psittaci :-
TO
VIOL
LU
Fam. I. Palæornithidæ. Two carotids. Ambiens ab-
sent. Oil gland present.
Subf. (1.) Palæornithinæ. Palæornis, Eclectus, Apros-
mictus, Eos, Tanygnathus, Prioniturus, Psittinus,
Loriculus, Trichoglossus, Lorius.
Subf. (2.) Cacatuinæ. Orbital ring complete.
Calopsitta, Calyptorhynchus, Licmetis, Eolo-
phus, Cacatua.
Subf. (3.) Stringopinæ. Furcula lost.
Stringops, Euphema, Geopsittacus, Melopsitta-
cus, Agapornis.
Fam. II. Psittacidæ. Left carotid superficial.
Div. A. Ambiens present.
270
STRUCTURE AND CLASSIFICATION OF BIRDS
Subf. (4.) Arinæ. Ara, Conurus, Bolborhynchus,
Caica, Psittacus, Peocephalus, Nestor.
Div. 6. Ambiens absent.
Subf. (5.) Pyrrhurinæ. Pyrrhura, Lathamus, Cora-
copsis, Pyrrhulopsis.
Subf. (6.) Platycercinæ. Furcula lost.
Platycercus, Psephotus, Cyanorhamphus, Psit-
tacula.
Subf. (7.) Chrysotinæ. Oil gland lost.
Chrysotis, Pionus, Brotogerys.
A phylogenetic tree accompanies GARROD'S scheme, in
which it is assumed that the ancestral parrot possessed the
normally running carotids, an ambiens, an oil gland, and a
complete furcula. From this the main stems are given off,
in one of which the carotids remained normal, while in tho
other the left became superficial. The loss of the other
characters leads to further branching of both main branches.
The Stringopinæ, especially Stringops itself, are the
nearest living representatives of the ancestral stem.
FÜRBRINGER / also argues for the low position of Strin-
gops, in contradiction to MARSHALL, who holds that it is an
extremely modified form. Its owl-like plumage, defective
carinal keel, and associated loss of the power of flight are
undoubtedly modifications, but it seems more probable that
they are modifications of an ancient than of a modern type
of parrot. FÜRBRINGER'S views are chiefly based upon the
flexibility of its anatomical characters. I have already
referred to the variability of the ambiens : the sternum offers
another fact of the same kind ; sometimes it is entire, without
notches or foramina, sometimes there are one or two upon
one or the other side, and occasionally two incisuræ, one
upon each side. This variability must not be associated, as
variability may often be associated, with a rudimentary
structure; the xiphosternum is not rudimentary, though
the keel is.
!. Einige Bemerkungen über die Stellung von Stringops,' &c., Journ. f. O.
1889, p. 236.
PSITTACI
271
UU
Mr. PARSONS and I have pointed out certain likenesses
between Stringops, the Cacatuinæ of GARROD, and Nestor,
which he places in an altogether different family. These
partly concern the syrinx, to which attention has been
already directed, partly the muscular system. In those birds
the posterior deltoid is larger than the anterior. It may be
noted also that powder-down patches are best developed and
more universal among the Cacatuinæ, while it is in that
family only that the gall bladder exists.
Of extinct parrots among the most remarkable is Lophopsitta-
cus mauritianus, characterised, as was also Necropsittacus rodcri-
canus, by its enormous jaws.
The principal interest attaching to other remains of parrots is
the light that they throw upon the former distribution of the
group; for Psittacus has been found in the lower Miocene of
France.
The determination of the affinities of the parrots to other
groups of birds is one of the hardest problems in ornithology.
They have been likened to the Accipitres (mainly, perhaps,
on account of the hooked beak and its cere), and to the
gallinaceous birds, in the neighbourhood of which they were
placed by GARROD. It seems to me that the parrots, like
the cuckoos, are a group of birds which are on the border-
land between the Anomalogonatæ and the higher birds. It is
remarkable what a number of points there are in which they
show resemblances to the Passeres—the complicated muscu-
lature of the syrinx, the absence of biceps slip and expansor
secundariorum, the presence of a cucullaris propatagialis,
found in the Passeres and in the somewhat passeriform
Upupa and Pici, the small number of cervical vertebræ, the
total want of cæca, allying them not certainly to the Passeres
but again to the Pici and many Anomalogonatæ, the reduced
clavicles of some genera. Zygodactyle feet, moreover, are
not found among the higher birds except in the Cuculi and
i Sir E, NEWTON and H. GALOW, 'On Additional Bones of the Dodo and
other Extinct Birds of Mauritius,' &c., Tr. Zool. Soc. xiii. p. 281. See also for
a figure and account of this bird NEWTON'S Dict. Birds, sub voce Ex-
termination.'
272.
STRUCTURE AND CLASSIFICATION OF BIRDS
the Musophagi, which are, similarly to the parrots, on the
border line between the Anomalogonatæ and higher birds.
It is noteworthy also that of the Anomalogonatæ which
present a catapophysial canal (found at any rate in one
parrot) it is the Pici and the passerine alone. But while it
is not so difficult to point out likenesses to the Anomalo-
gonatæ it is much harder to indicate resemblances to any
of the higher groups of birds. It must be held, in my opinion,
that they have emerged from a low anomalogonatous stock
at a time not far removed from that at which the Cuculi and
Musophagi also emerged, but that there is not a common
starting point of the three groups.
CUCULI
Definition.-Feet zygodactyle by reversion of fourth toe. Skull
desmognathous, without basipterygoid processes.' Oil gland
nude. Quintocubital. Two carotids. Cæca longish. Ambiens
present.
The family which is defined by the above characters is a,
large one, comprising, according to the recent catalogue of
Captain SHELLEY, 165 species, which are distributed by
that ornithologist into forty-two genera.
. The family is almost world-wide in range, being most
abundant, however, in the tropics. Correlated with its
numerous genera and species and wide range we find a
certain amount of structural variation in the family, which
permits of its division into several subfamilies, concerning
the number and extent of which there is some divergence of
opinion. It may be convenient, however, to consider the
general anatomy of the family before dealing with its major
subdivisions.
Apart from the facts used in the definition of the family
the cuckoos are characterised by the absence of, or the
presence of only a rudimentary, aftershaft to the contour
feathers. The number of rectrices is not, as was stated by
NITZSCH, constantly ten; for in Saurothera, Guira, and Croto-
| Well-marked rudiments in Rhinococcyx and Eudynamis.
CUCULI
273
phaga there are only eight. The feather tracts are somewhat
diverse in their disposition. The pterylosis of the European
cuckoo (Cuculus canorus) has been described by NITZSCH in
his · Pterylography. The feathering on the throat com-
pletely occupies the intermandibular space. The ventral
pteryla is divided upon the neck into its two halves, which
are not again divided ; each passes backwards, gradually

FIG. 134.—PTERYLOSIS OF Eudyramis Orientalis. VENTRAL VIEW.
(AFTER BEDDARD.)
diminishing in extent, until it ends in a single row of feathers
in the neighbourhood of the cloaca. Over the sternum this
pectoral tract is very wide ; later its three rows of feathers
become separated by a slight interval, two on one side and
one on the other, which, however, reunite before ending at
the cloaca. The spinal tract is narrow in the neck region.
It bifurcates on the shoulder to enclose a lanceolate space.
. ..: T:
274
STRUCTURE AND CLASSIFICATION OF BIRDS
S
Of other cuckoos whose pterylosis has been studied ' Caco-
mantis, Piaya, Saurothera, Diplopterus, Coccyzus, Chryso-
COCCYl, and Coccystes agree in most points with Cuculus.
But in the American genera Piaya, Diplopterus, Saurothera,
and Coccyzus, the ventral tract is double from the very first
--that is to say, in the mandibular region.
A more complicated pterylosis characterises certain other

11
11
1
.
Fig. 135.-PTERYLOSIS OF Piaya cayana. DORSAL VIEW. (AFTER
BEDDARD.)
cuckoos. In the genus Centropus the feathering upon the
throat is close and continuous, the two ventral tracts diverg-
ing at about the junction of the neck and trunk. Each of these,
: BEDDARD), 'On the Structural Characters and Classification of the Cuckoos,'
P. 2. S. 1885, p. 108; SHUFELDT, . Contributions to the Anatomy of Geococcyx,'
ibid. 1886, p. 966.
. CUCULI
275
again, divides into two separate tracts, of which the inner
is at first two feathers wide, which number is reduced to one
just before the termination of the row a little way in front of
the cloacal aperture. The outer branch consists of one row
only, and terminates some way in front of the end of the inner
branch, without, however, showing any signs of being fused
with it. Pyrrhocentor, Geococcyx, Crotophaga, Eudynamis,
Y

1
.
•
.
.
10
102
O
20
::
FIG. 136.—PTERYLOSIS OF Piaya cayandı. VENTRAL VIEW.
(AITER BEDDARD).)
U
Scythrops, and Phoenicophaes have a pterylosis which is much
like that of Centropus. The two types of pterylosis observ-
able in the cuckoos are illustrated in the accompanying wood-
cuts. Unfortunately the pterylosis of some important genera,
such as Coua, is not known.
All cuckoos possess the ambiens. In all cuckoos we also
find the semitendinosus, the accessory semitendinosus, and
11
16
T
2
276
-
STRUCTURE AND CLASSIFICATION OF BIRDS
the femorocaudal; in Centropus and its allies, both in the
Old World and in the New, the accessory femorocaudal is
also present. In many groups of birds the arrangement of
the tendons ending in the patagium is very complicated.
This is not the case with the Cuculi, where the disposition of
these tendons is very uniform. For the most part the sim-
plicity is suggestive of the perhaps allied picarian birds. In
Cuculus canorus, for example, which has been figured by
GARROD, the tensor patagii brevis is inserted on to the fore
arm without any bifurcation. So too in Piaya, Saurothera.
The only exception to this which has been noted occurs in
Geococcyx, where the said tendon bifurcates just before its
insertion, the anterior branch being inserted on to the exten-
sor metacarpi radialis a little way in front of the main
attachment. This is also the case with Guira and Phonico-
phaes.
No cuckoo has any biceps slip. In some genera, e.g. in
Saurothera, Coccyzus, Pyrrhocentor, there is an attachment
between the anconæus and the humerus. In Guira there
is none. The expansor secundariorum is what GARROD
(see p. 85) has termed ciconiiform. The gluteus primus
is extensive in most cuckoos ;? its origin in them reaches
behind the head of the humerus as well as in front. There
is no glutæus V. The deep plantar tendons of Pyrrhocentor
and Centropus are peculiar in that no branch is sent to
the hallux.
The syrinx in the cuckoos shows greater variability than
in any other group of birds excepting the goatsuckers. We
meet with the typical tracheo-bronchial syrinx in a consider-
able number of genera, while in others is the much-modified
bronchial syrinx. The latter was first described many years
ago in Crotophaga by JOHANNES MÜLLER. In that genus
the syrinx closely resembles that of Steatornis, which has
been already described in the introductory chapter (see p. 69).
There are, however, as might be imagined, differences of
detail. In Crotophaga the membrana tympaniformis com-
mences at the seventh ring of the bronchi, the rings in front
Apparently absent or very slight in Cuculus.
CUCULI
277
.
-
17
-
.
.
I
.
TAS
.
,
-
being perfectly complete rings, the trachea dividing, 'as in the
mammalia. From the seventh onward all the bronchial rings
are semi-rings, the intrinsic muscles being attached to the
tenth. This is one extreme of the series, the other being
offered by such a type as Piaya. In Piaya (see fig. 137.)
there is a purely tracheo-bronchial syrinx. The third bron-
chial semi-ring is of compara-
tively speaking enormous size,
and to it are attached the in-
trinsic muscles of the syrinx. In
Saurothera we have a syrinx
which is quite similar save for
the fact that the third bron-
chial ring is not enlarged.
Diplopterus is much the same
as the last. Cuculus has also
a perfectly typical tracheo-bron-
chial syrinx. In Eudynamis
there is a cuculine syrinx, the
last tracheal and the first three
bronchial semi-rings being ossi-
fied; the intrinsic muscles are
attached, as in Praya, to the FIG. 137. -SYRINX OF Piaya cayana
third bronchial semi-ring.
(AFTER BEDDARD).
Phænicophaes is much the same.
The remaining genera of cuckoos whose syrinx is known
are nearer akin to Crotophaga, though in them the bronchial
syrinx is not quite so typical. In Centropus ateralbus, for
instance, the first fifteen rings of the bronchi are incomplete
internally and are closed by membrane, but the membranous
area is narrow; this area widens out at the sixteenth ring,
which with the following is much stronger than the pre-
ceeding and succeeding rings of the bronchus; to the sixteenth
ring are attached the intrinsic muscles of the syrinx. Pyr-
rhocentor and Geococcyx have a similar syrinx. The syrinx of
Guira is in many respects very remarkable. On a superficial
view it is not unlike that of Cuculus. The voice organ in
this genus is placed further forwards than in the genera just

*
278
STRUCTURE AND CLASSIFICATION OF BIRDS
considered. But the first two or three rings of the bronchus
are complete rings with no membrane internally. From the
fourth onwards the rings are semi-rings. Upon the sixth
are inserted the syringeal muscles. Coua is somewhat inter-
mediate. The first seven bronchial semi-rings have their
inner extremities separated by a narrow area of membrane.
To the seventh are attached the intrinsic muscles of the
syrinx. From this point commences the tympaniform mem-


a
WA
2
.
AIR
!
.
*
"
/
.
she
w
*
.
.
.
STA
**
A
*
-
*
--
*..
JA*
ZO
.
i
-
FIG. 138.--SYRINX OF Centropus ateralbus (AFTER BEDDARD).
A. FRONT VIEW. B. BACK VIEW..
brane. The accompanying woodcuts will serve to illustrate
the varying form of the syrinx among the Cuculi.
As with some other large groups of birds, such as the
pigeons and parrots, the gall bladder is present in some
cuckoos and absent in others. The gall bladder exists in
the genera Saurothera, Coccyzus, Guira, Pyrrhocentor,
Scythrops, and Cuculus; it is absent in Crotophaga and in
some species of Centropus. Coua has a gall bladder ; Eudy-
namis appears not to have one.
In Gura the right lobe of the liver is five or six times as
large as the left.
The main artery of the leg is the femoral in Piaya, Cen-
tropus, the sciatic in Diploptera, Saurothera, Coccyzus,
Pyrrhocentor.
CUCULI
279
The following are some intestinal measurements, princi-
pally of the cæca :-
S. I.
į
L. I.
I
Ca.
-
-.-
.
-
-
Inches
Inches
18
1.8
Inclies
1.1
1.4
8
1.7, 1.5
1.2, 1.1
1.3
1.5
Har
CCIILOI'US .
Piaya cayana . .
Diplopterus ncevius .
Saurothera dominicensis
Coccyzus americanus.
Pyrrhocentor celebensis
Centropus ateralbus
2 phasianus.
Phonicophaes sp.
Geococcyx affinis .
Crotophaga sulcirostris
Guirá piririgua :
Scythrops . . .
Chrysococcyx . .
16
1.75, 1.5
2.25
2.25
1.75
13
12
15
1.5
4.5
20.
6.5
9
As for the skull of the cuckoos, that of Scythrops has been
described by PARKER 1 and by myself. SHUFELDT has
studied the skeleton of Geococcyx.3 Scythrops is doubly des-
mognathous, the maxillo-palatines being united for their whole
lengths, and the palatines also being fused with each other
posteriorly. In other cuckoos the maxillo-palatines diverge
posteriorly for a short space, and there is no union between
the palatines. Scythrops has, according to PARKER, two
small vomers, situated one behind the other. In cuckoos the
ectethmoid processes are large, and the lacrymal has often
(e.g. Scythrops, Crotophaga) a large descending process
nearly touching the jugal. Scythrops and Eudynamis have an
os uncinatum lying between the descending process of the
lacryinal and the ectethmoid.
The holorhinal nostrils are much obliterated by bony
growths, the degree varying. As a consequence the nostrils
are as a rule impervious; but in the dried skulls of Pyrrho-.
centor and Cuculus there is a considerable foramen.
No cuckoo has more than fourteen cervical vertebræ, and
some have only thirteen. Three or four ribs only articulate
U
Trans. Linn. Soc. (2), i. 2 P. Z. S. 1898.
J. Anat. Phys. xx. 1886, p. 244.
I could only find one lying entirely between the palatines.
280
STRUCTURE AND CLASSIFICATION OF BIRDS
with the sternum. The sternum may be fenestrated or
marked by posterior incisions.
The atlas of Rhinococcyx' is perforated by the odontoid
process ; C11-D1 have hypapophyses in addition to the axis,
and two or three following, C12-14, have also catapophyses,
which on 14 ascend on to the hæmapophysis.
In Saurothera C10 has closely applied paired hæmapo-
physes.
The modifications of the syrinx, the pterylosis, and the
leg muscles permit the family to be subdivided thus, the
subdivisions, as will be observed, corresponding to the
geographical range of the birds :-
Subfamily I. Cuculinæ. Syrinx tracheo-bronchial. Ven-
tral feather tract single. Muscle formula AXY+.
A. Ventral tract single at commencement.
Cuculus
Chrysococcyx loid World
Cacomantis
Coccystes (?)
6. Ventral tract double at commencement..
Saurothera
Diplopterus (?)
New World.
Piaya
Coccyzus
Subfamily II. Phoenicophainæ. Syrinx tracheo-bronchial.
Ventral feather tract bifurcate. Muscle formula
ABXY+.
Scythrops
Eudynamisfold World.
Phænicophaes )
Subfamily III. Centropodinæ. Syrinx bronchial. Ven-
tral feather tract bifurcate. Muscle formula
ABXY.+.
I. CU
In Scythops there is a notch nearly completely converted into a foramen;
in Eudynanis a notch less nearly converted into a foramen, also in Guira and
Diploplerus. In Criculus and Saurothera there is a foramen.
CUCULI
281
a. Ventral tract occupying whole of space between
jaws.
Pyrrhocentor
Centropus Old World.
Coua (?)
6. Ventral tract only occupying median region.
Geococcyx
Crotophaga New World.
Guira
O
The question of the affinities of the cuckoos is a difficult
one.
By GADOW they are placed nearest to the Musophagi and
next nearest to the Psittaci. FÜRBRINGER'S views do not
greatly differ. There seems to be no doubt that these birds
are an archaic group not far from the point where the Ano-
malogonatæ and Homalogonatæ of GARROD diverge. They
are, like the Musophagi, quintocubital; their intestines are
simple; and they have the complete muscle formula (B being
in some forms absent). These characters are found in others
among the more primitive of the higher birds.
The likenesses which the cuckoos show to the Pico-Pas-
seres are mainly in the structure of the foot, in the simple
character of the tendons of the patagium, and the marked
resemblance in the syrinx to that of the Caprimulgi, and in a
less degree to the Striges. As has been pointed out, precisely
the same series of modifications between the extreme bron-
chial syrinx of Crotophaga and the purely tracheo-bronchial
syrinx of Cuculus are to be seen among the Caprimulgi. The
syrinx is really the only salient point in the anatomy of
the group that can be laid hold of for purposes of com-
parison, and, considering the dissimilarities in the voice and
habits of cuckoos and goatsuckers, it is particularly note-
worthy.
As to fossil cuckoos, the two most interesting facts are,
perhaps, the occurrence of Centropus and Phoenicophaes' in
See MILNE-EDWARDS in Comptes Rendus for 1894.
LI
|
12.1)
LOU
282
STRUCTURE AND CLASSIFICATION OF BIRDS
Europe, especially the latter, as it has some claims to repre-
sent the most ancient form of cuckoo, with complete muscle
formula and tracheo-bronchial syrinx.'
MUSOPHAGI
Definition.- Oil gland tufted. Aftershaft present. Quintocubital.
Rectrices, ten. Muscle formula of leg, ABXY+. Expansor
secundariorum present. Biceps slip absent. Cæca absent. Both
carotids present. Skull holorhinal, desmognathous, without
basipterygoid processes.
LU
This group of birds, purely African in range, is divisible
into three genera, Corythaix, Musophaga, and Schizorhis.
These genera do not show a large amount of structural
variation.
As to the pterylosis, the two ventral tracts are double
upon the neck in C. albocristata); they remain separate
until just in front of the cloaca, being especially weak and
narrow in the breast region. Longitudinally arranged rows
of feathers connect the pectoral tracts above with the
humeral. The other important external characters are stated
in the definition.
In Schizorhis the normal arrangement of the leg arteries
obtains.
In Corythaix and Musophaga the femoral artery is the
one developed. The right jugular is the largest, and in
Corythaix albocristata seems to have entirely disappeared.
In the liver the right lobe is the larger,3 sometimes
considerably so. The gall bladder is present, and sometimes
is elongated in form. The tongue is short and triangular ;
the proventriculus is zonary, the gizzard weak. The in-
testines are capacious and short, without cæca. The following
are a few measurements :
Cf. also partial persistence of basipterygoid processes in Phæpicophaine.
? The extinct Necrornis of French Miocene may be a Touraco.
3 The viscera are described by Owen for Corythaix porphyreolophai, P. Z. S
1834, p. 3, and by MARTIN for Corythaix Buffonii, ibid. 1836, p. 32.
MUSOPHAGI
283
BE
1920
YOND
Corythaix erythrolophus . . . . . 17 inches
albocristata .
o persa .
Musophaga violacea.
Schizorhis africanus
The windpipe of Corythaix persa is slightly swollen
along its course, narrowing again at the bifurcation. It is
much ossified. Counting as
the last tracheal ring that to
which the pessulus is attached
in front, the intrinsic muscles
are inserted on to the third
in front of this. The first
two bronchial semi-rings are
ossified; the third, between
which and the second there is
a considerable membranous
interval, is the first of the
purely cartilaginous series.
The extrinsic muscles are
stout, and arise seven or eight Fig. 139.-INTESTINES or Corythaix
chlorochlainys (AFTER MITCHELL).
rings from the end of the
2, short-circuiting vessel dividel.
trachea, and pass at once to
their insertion; they run no distance along the trachea, as is
so common.
Musophaga has no intrinsic muscles ; Schizorhis has.
As to muscles, the tensores patagiï are very simple, and
the biceps slip is entirely absent.
The tensor brevis sends off a wristward slip just before
its insertion in both Musophaga and Corythaix ;? it is
reinforced by a pectoral slip and by a fibrous slip from the
humeral crest.
The anconcus longus has not, at any rate in Corythaix
albocristata, a humeral head. Gluteus I. is large, covering
the biceps; gluteus V. is absent (Corythaix erythrolophus,
Musophaga) or present (Schizorhis africanus). The muscle

GAST
UU
-
7
U
| Absent-perhaps as an individual variation-in C. albocristata.
284
STRUCTURE AND CLASSIFICATION OF BIRDS
formula of the leg, as stated in the definition, is ABXY+.
Both peroneals are present. The deep flexor tendons are
bound by a vinculum, which is single in Corythaix and
double in Schizor his.
The skull of Corythaix is barely desmognathous, and
by no manner of means especially like that of a cuckoo,
to which group the Musophagi have been often compared.
The hinge in the middle of the face is nearly complete, but
there is a bridge on each side, formed by an ankylosis
between the frontal and nasal. The holorhinal nostrils are
situated very far forwards, and each has, as PARKER' has
pointed out, an osseous fold upon the ossified internarial
septum. The maxillo-palatines diverge from each other
posteriorly for a much longer space than in any cuckoo.
The ascending laminæ of the palatines come into contact
for a very brief space over the rostrum in front, and are
continued forward for a short distance as a sharp spike.
Between them lies a minute interpalatine splint (or vomer).
The interorbital septum is moderately fenestrate. The
lacrymal bones are of some size, and the descending process
is closely applied to, but does not fuse with, the square
ectethmoid process ; connected with both is a small os
uncinatum, which reaches the palatine.?
UI

..
.
-
Cuculi
Musophagi
-
+
--
.
.
. .
.
Bony nostrils . . Close to fronto-nasal Near end of bill.
hinge.
Ectetmoid . . Continuous with dorsal! Not so continuous.
wall of orbit.
Palatines
Ascending laminæ come Ascending lamine come
into contact posteriorly into contact anteriorly
for a considerable for a short space.
space.
Maxillo-palatines . More completely fused. i Less completely fused.
Jugal bar
. Expanded where it joins Not expanded ; junction
maxilla on, or close to, with face higher up,
ventral surface.
very much as in
parrots.
-
--
.
-
-
In view of the general opinion as to the nearness of the
1
1 In his paper upon Opisthocomus. See below, p. 286, footnote ?
2 J. T. REINHARDT, Vid. Medd. Kjöbenhavn, 1871; p. 326.
MUSOPHAGI
285
CU
U
alliance between Musophagidæ and Cuculidæ it may be
useful to tabulate the principal divergences in the skull.
: Corythaix has 14 cervical vertebræ ;' the atlas is notched,
not perforated by the odontoid process. Four ribs reach
the sternum, which is doubly notched and has a strong
spina externa.
. In the pelvis the prepubic process is very markedly
developed, as in Geococcyx.
The clavicle comes into contact both with the scapula
and with the moderately large procoracoid; the latter is
fused with the acrocoracoid,? making thus a complete bridge
over the sulcus supracoracoideus. The coracoids slightly
overlap at their articulation with the sternum.
The hæmapophyses are characteristic. In Corythaix albo-
cristata C11 has paired processes ; on C12 and C13 the hæma-
pophyses form a continuous ventral keel to those vertebræ.
The three following vertebræ have hæmapophyses. The
extremities of those of D1 and D2 are expanded with a
median ridge, owing to the catapophyses having descended
them.3
CU
Y
OPISTHOCOMI
Definition.--Aftershaft present. Oil gland feathered. Rectrices, ten.
Quintocubital Muscle formula, ABXY+. Biceps slip and
expansor secundariorum present. Carotids, two. Cæca present.
Skull holorhinal, schizognathous, without basipterygoid pro-
cesses. Sternum peculiar in form, wider behind than in front;
the spina externa ankylosed with furcula.
There is no doubt that this group, consisting of but
a single genus and species, Opisthocomus cristatus, the
hoatzin of British Guiana, forms a well-marked group of
birds.
The external characters of the adult and young have been
chiefly described in recent years by NITZSCH, PYCRAFT, 4 and
In Corythaix persa the atlas ring is incomplete.
2 Cf. Galli, in which the same fusion occurs.
3 E. BLANCHARD, “Remarques sur l'Ostéologie des Musophagides,' Compt.
Rend. xlv. p. 599.
4. On the Pterylography of the Hoatzin,' Ibis, 1895, p. 345.
286
OF BIRDS
n
STRUCTURE AND CLASSIFICATION VW
16
,
i
myself,' the internal anatomy of the soft parts by PERRIN,2
GARROD, 3 GADOW," MITCHELL," and myself.
The pterylosis of Opisthocomus shows a less sharp differ-
entiation into pteryla and apteria than in many birds; many
of the spaces are covered with a sparse feathering of semi-
plumes. This condition may be, as GARROD has suggested,
immediately derived from a continuous feathering. Never-
theless there is a sharply marked apterion upon the carina
sterni, which is necessarily, therefore, of limited extent. The
dorsal apterion is but feebly marked. In the young chick
the ventral apterion was as clear as in the adult, but I could
discover no trace of a dorsal bare space. In the young un-
hatched chick the ventral feathering was closer than the
dorsal.
. The skin lying upon the carina sterni is dense and thick-
ened, a state of affairs which appears to have some relation
to its habit of squatting close to the branch upon which it is
resting
The principal recent papers upon the osteology of this
bird are those of HUXLEY" and the more recent and more
elaborate treatise of PARKER.? The cervical vertebræ are
nineteen in the adult ; but PARKER found only eighteen in
the unhatched young. The atlas is notched for the odontoid
process. Hæmapophyses are very feeble. The last two or
three cervicals are ankylosed with each other, and form part
of the dorsal series of ankylosed vertebræ. There is some
T11
2
1. Contributions to the Anatomy of the Hoatzin,' &c., Ibis, 1889, p. 283.
See also C. G. Young, ' On the Habits and Anatomy of Opisthocomus cristatus ;'
Notes Leyden Mus. X. p. 169 ; and J. J. QUELCI, 'On the Habits of the
Hoatzin,' Ibis, 1890, p. 327.
2. On the Myology of Opisthocorus cristatus,' Tr. Zool. Soc. ix. p. 353.
8 "Notes on Points in the Anatomy of the Hoatzin,' P.Z. S. 1879, p. 109.
1.Description of the Modification of certain Organs,' &c., 200l. J.B. v. Abth.
Syst. v. 1891, p. 629, and Proc. R. Irish Ac. (3), ii. p. 147.
See below, p. 288, footnote, for reference. See also a recent paper
by GOKLDI in Ornith. M.B. May 1895, and more fully in Bol. Mus. Para.
1895.
On the Classification and Distribution of the Alectoromorphæ,' P. 2. S.
1868.
7. On the Morphology of a Reptilian Bird, Opisthocomus cristatus,' Tr. 2. S.
1891.
OPISTHOCOMI
287
TY
.
variation as to the number of cervical vertebræ, which bear
long rib stylets. As a rule five complete ribs exist, of which
all bear uncinate processes. The sternum (see fig. 140) is ex-
ceedingly remarkable in its form. It is wider behind than in
front, with a pair of notches, and outside of these a pair of
foramina ; the keel is shorn away anteriorly, but well deve-
loped posteriorly. The furcula, which is shaped like a fork
with nearly straight lines, is completely ankylosed on the
one hand with the coracoids, and by its median region with
Lul

.
S
-
.

.-
.
NARNIR
os
"
.
"
put
.
.
SE
.
www.
*
1
.
Inne
..
..
SOWIE
i
.
To
.
1
ED
.
-
!!
2
Cik
..
.
-
1
-
*
SOSYS
FF
he
www.
MIT
.
.
-
.
'
1' I
.
!
.
PS
1
.
34..--
Fig. 14:0:-STERNUM OP Opisthocomus.
SIDE VIEW. (AFTER Huxley.)
I'IG. 141.--STERNUM OY Opis-
thocomus. FRONT VIEW.
(AFTER HUXLEY.)
the spina externa sterni. The region of the furcula, however,
which comes into contact with the sternum was found by
PARKER to be a separate 'needle of bone,' which he regarded
as the interclavicle (see p. 131). The scapula is provided in
the young with a distinct suprascapula, segmented off from
the scapula.
The pelvis is especially compared by HUXLEY with that
of Coturnix ; it has no ileo-pectineal processes.
288
STRUCTURE AND CLASSIFICATION OF BIRDS
11
102
UVITU
In the skull the rostrum is articulated with the frontal
region by a well-marked hinge. The skull is holorhinal,
schizognathous, and there are no basipterygoid processes.
The vomer is expanded and bifid in front in a fashion that
recalls the ægithognathous skull and that of certain of the
Charadriiformes (see below).
In the young skull PARKER figures basipterygoid pro-
cesses, not, however, articulating with the pterygoids ; they
appear to be not unlike those of Aptornis (see below). The
holorhinal nostrils are partly obliterated by an ossified ali-
nasal, as in so many picarian and passerine birds.
The alimentary canal of Opisthocomus is remarkable in.
more than one way. There is, in the first place, the enormous
crop, which has been most recently and most fully described
by GADOW. This organ is very large, and rests upon the
furcula and the fore part of the sternum, for the abortion of
the anterior part of whose keel GADOW thinks the crop is by
its pressure responsible. The crop too is exceedingly muscu-
lar, and has numerous parallel folds in its interior, some of
which are continued into the oesophagus below. The gizzard
is much reduced in size. Probably the crop is not a mere
storehouse, but a compartment where at least trituration of
the food (chiefly leaves) takes place.
The most remarkable feature about the intestinel is
the long and coiled rectum, a feature which is also found
among the struthious birds and in the archaic Chauna.
The general arrangement of the coils of the small intestine is
intermediate between those of Pterocles and pigeons. There
is in the middle loop a faint trace of the spiral found in the
corresponding loop of the pigeon's gut. There are also like-
nesses to the form of gut in the cuckoos. The cæca are
fairly developed.
The peculiarities of the muscular system mainly concern
the hind limb, and chiefly characterise the ambiens. The
muscle formula is complete, i.e. ABXY+. The ambiens,
however, is subject to variation. GARROD found that in all
I P. CHALMERS MITCHELL, ' A Contribution to the Anatomy of the Hoatzin
(Opisthocomus cristatus),' P. Z. S. 1896, p. 618.
OPISTHOCOMI
289
/
WS
WIS
TA
ES
1
-
.
..
.......
.
..
.
.
...
..
1119'
of six knees that he examined the ambiens was present,
though small; but in only one knee did it cross the knee to
be inserted in the usual fashion in connection with the flexors
of the leg. MITCHELL dissected this muscle in two specimens;
in one the ambiens was completely absent above the knee,
but in each case (see fig. 53, p. 96) a ligament left the fibula,
and, dividing into three, joined each of the three perforated
flexors in the way in
which, as has been
already described, it oc-
curs in birds which have
this ambiens rudiment.
In the second case there
was an ambiens above
the knee, but it became
lost upon the fascia of
the knee, and not con-
nected with the ambiens
rudiment springing from
the fibula, which was
there present. So in
this bird there are many
stages in the reduction
of this characteristic
muscle, which is clearly
in them on the wane.
It is apparently the me
FIG. 142.-SYRINX or Opisthocomus. FRONT
rule among birds for - VIEW. (AFTER GARROD.)
there to be a vinculum
between the two superficial flexors of digit III. This slip
is wanting in Opisthoconus, as it is, according to MITCHELL,
in Asio otus and Rhytidiceros plicatus. The deep flexor
tendons are connected by a strong vinculum.
The syrinx has been described by GARROD and myself.
The accompanying figure is from GARROD'S paper. The
last few rings of the trachea are solidified into a tracheal box,
and the intrinsic muscles do not reach this box, being only
continued on to it by a ligamentous continuation. There is

.
1.0; olosi Bogorbeeld
it.
Innihamisu
SISIMAIS
D
AHA
4:19
Oi
YI
WL
IDUM
!,
Sildid
*
WWW
SOUL
itts
HU
*****
Hyvin
.
.
.
K
.
S
WWW012
el
HAWI
.
.
w
.
.
***
no
10. Vem
ADIR
www.
13 .4
.
T ui
H
raun
..
..
1.
Wit2
WORT
!
Mt.
.
Latte DIIRNISMI
..
"
-290
STRUCTURE AND CLASSIFICATION OF BIRDS
some variation in the number of rings which coalesce to form
the box, while the fibrous continuation of the intrinsic muscles
may reach the first bronchial semi-ring. This muscle is
evidently decaying in Opisthocoinus.
$.
GALLI 1
Definitio12.- Quintocubital birds with an aftershaft. Muscles of leg
generally ABXY +. Expansor secundariorum present. Entepi-
condylo-ulnaris present. Cæca large ; à crop present. Skull
schizognathous, holorhinal, with sessile basipterygoid processes.
Palatines without internal lamina.
This very large group of birds, universal in range, shows
a considerable amount of structural variation.
The oil gland is generally tufted ; a but it is nude in the
Megapodes and absent altogether in Argus.
The pterylosis of the Galli is, according to NITZSCH,
singularly uniform. He figures Gallus bankiva, Pavo
cristatus, and Meleagris gallo-pavo, describing also a few
other types. There are lateral neck spaces in all; the dorsal
tract is single in Gallus, widening out on the back; in the
peacock it widens out in a more pronounced fashion and
further back than in Gallus. In the turkey there is a
narrow space in it between the shoulder blades.
The ventral tract divides early upon the neck, and each
tract gives off on the breast a wider, denser outer branch;
the two median tracts then continue nearly to the cloaca,
where they unite.
In Perdix and Tetrao there is a dorsalspace, as in Meleagris.
Among the Cracidæ there may or may not be a space in
the dorsal tract.
The pectoral muscles of gallinaceous birds, like those of
the tinamous, meet over the keel of the sternum ; this is at
least the case with Euplocamus Vieilloti and some others.
I H. SEEBOHM, ' An Attempt to Diagnose the Sub-Orders of the Great Galli-
naceo-Gralline Group of Birds by the Aid of Osteological Characters alone,' Ibis,
1888, p. 415.
? Callipepla californica has a small tuft; in C. squamata I have observed
both the complete absence of a tuft and the presence of a very small one.
GALLI
291
IL
Y
The deltoid may or may not possess a special tendinous
slip from the scapula. This slip is absent in Mitua tomentosa,
Excalfactoria chinensis, and Callipepla, but present in
Ortalis albiventris, Crax Sclateri, C. Daubentoni, Crosso-
ptilon mantchuricum. It is evidently, therefore, not of great
use in classifying the group.
The biceps slip is generally present, but absent in
Ortalis albiventris, Crax, Mitua; it is present in Megapodius
and Megacephalon;] absent in Talegalla, Niinida, and
Meleagris. The same remark may, therefore, be made about
this muscle. The humeral head of the anconcus is not
always presént.
The tensor patagiż brevis of gallinaceous birds has a
thin, wide, diffused tendon, as in the tinamous; there is no
patagial fan..
The entepicondylo-ulnaris is another muscle which they
share with the last-mentioned group.
The expansor secundariorum is a muscle which appears
to be invariably present among the Galli, but to have vary-
ing relations at its scapular insertion.
'In the majority of the gallinaceous birds,' wrote Pro-
fessor GARROD,“the expansor secundariorum, with the normal
origin from the secondary quills, has a different method of
insertion, which has led M. A. MILNE-EDWARDS to describe
the muscle in the common fowl as a part of the coraco-
brachialis (brevis) in his superb work on fossil birds.
'In the genera Tetrao, Francolinus, Rolluilus, Phasianus,
Euplocamus, Gallus, Ceriornis, and Pavo, the muscle, instead
of being inserted into the scapulo-sternal fibrous band, above
referred to, after blending to a certain extent with the axillary
margin of the teres, ceases by becoming fixed to a fibrous
intersection about one-third down the coraco-brachialis
brevis muscle.
'In Francolinus Clappertoni from among the francolins,
Coturnix, Odontophorus, Ortyx, Eupsychortyx, and Numida,
the tendon does not go so far as the short coraco-brachialis,
but ends either by simply joining the axillary margin of the
? Absent, according to FÜRBRINGER.
r 2
292
AND CLASSIFICATION OF BIRDS
T
STRUCTURE 11
tereś or by at the same time sending a tendinous slip
behind it to the scapula. In Argus giganteus the tendon,
running from the elbow, turns round the axillary border of
the teres to end by joining a triangular muscular fasciculus,
attached by its base to the upper portion of the thoracic
surface, which appears to be nothing but a differentiation-off
of the upper portion of the last-named muscle. In the
Cracidæ this insertion into the scapula is also found, but it
is tendinous, like the upper element of the thoracic band
above described in the storks and Chauna ; and in them
there is also a second tendinous slip from the axillary margin
of the coraco-brachialis longus (not the brevis). In the Mega-
podidæ also the attachment to the coraco-brachialis brevis is
wanting, the tendon ending either by blending with the teres
margin or running on to the scapula.
The glutæus primus is a large muscle covering the
biceps. Gluteus V. appears to be always present, but is
sometimes (Thaumalea picta) quite tendinous.!
Most gallinaceous birds have the complete muscle formula
ABXY+. The femoro-caudal, however, varies in size,
and is quite absent in Pavo and Meleagris. It is very
slender in Crax and Ortalis.2
The deep flexor tendons belong to type I., and are illus-
trated in fig. 54 (p. 100).
There are two carotids in all but the Megapodes, where
the left only is present. A gall bladder is present.
Some intestinal measurements are given on p. 293.
The trachea has in a few gallinaceous birds two pairs of
extrinsic muscles, thus resembling, it will be observed, the
Anseres and Palamedeæ.
Thus in Crax Daubentoni, besides the usual sterno-trache-
ales, which arise in the ordinary way from the costal processes,
there are a pair of cleido-tracheales, springing from the
1 For the tail muscles of the peacock see HEMMING, Proc. Linn. Soc. 1844,
p. 212.
? ? GARROD has figured (in MS.) an abnormal Gallus domesticus with a
peculiar additional muscle springing by tendinous slips from femur, femoro-
caudal, accessory ditto, and semitendinosus, and running to gastrocnemius.'
It was the same on both sides.
GALLI
293
Name of Bird
Small Intest. Large Intest.!
Cæca
*
Inches
Inclies
Inches
-
56
-
-
50
..
8 and 9
6.5
.
39
44
3.5
3
3.5
u
ni
7.5
-
-
30
4.5
:
은
​84,
-
66
4.5
3.5
5.5 to 7.5
6.5
7.5
3.5
3.75
1
-
---
37
--
-
--
25
-
-------
-
5.25
--
-
2.5
-
-
-
----
22
A có A to V
-
2.5
-
--
18
-
-- -.-
3.5
3-5
.--
43
or
5.75
46
-
53
coño en
-
30
66
ser o
9
-
-
-
.
9 ܠ
-
Pavo cristatus .
9 nigripennis .
, muticiis .
, spicifer
Caccabis chukar .
Argus giganteus.
Ithaginis Geoffroyi : ..
Polyplectron chinquis .
ŠS 1 bicalcaratum .
Rollulus coronatus
Arboricola torqueola .
Coturnix communis .
Ortyx virginianus
, cristatus . .
, Gambelji . .
Odontophorus dentatus
Perdix cinerea .
Phasianus versicolor.
Thaunalea Amherstiæ
Euplocamus Swinhoii .
erythrophthalmus
Vieilloti.
nycthemerus.
cristatus . .
albo-cristatus .
Andersoni
nobilis . .
Ceriornis Temmincki .
i satyra . . ..
Lophophorus impeyanus
Crossoptilon wantchuricum
Lobiphasianus Bulweri .
Gallus bankiva .
Sonnerati.
Numida meleagris
ptilorhyncha .
2 cristata .
Edouardi
vulturina
Tetrao urogallus .
tetrix .
i phasianellus
1 cupido .
Meleagris ocellata
Francolinus afer .
»...gularis
Crax globicera ..
Sclateri .
Daubentoni.
, Alberti .
, globulosa .
Mitua tuberosa .
, tomentosa.
Penelope cristata .
.........................................................
ܒ
-
-
OD or
ст сл си с
-
-
ܠܕ
-
-
59
---
un modo da CO CO 10 * *200 m
-
-
-
61
-
--
6.5
10.5
39
54
6.25
.
61
35
ar
.
.
-
29
..
.
-
—
.
-
-
»
.
-
5.25
6
5.5
9 and 10
30.5
2.75
16
.
.
.
.
od #cco eü a
.
.
17
.
13.5
.
31
6
.
.
.
4.
7 and 8
4.5
6.5
126
S5
104
118
121
.
.
.
ܥܛ
.
123
.
6.5
55.
90
.
•
1 Penelo
2.5
.
294
STRUCTURE AND CLASSIFICATION OF BIRDS

Name of Biril
Small Intest. | Large Intest.
Cæca
Inchies
Inches
Iucles
48
2.5
2-5
29
36
3.5
42
2:75
4
#
Penelope cujubi.
cujubi.
pileata. .
jacucaca
Pipile jacutinga .
cumanensis
i Aburria carunculata
! Ortalis albiventris
Talegalla Lathami .
Megacephalon maleo.
-
-
-
51 a
56
40 min
#
-
...
2:25
i
4
2.5
24
72
.
.
5.5
anterior end of the sternum and from fibrous septum between
it and the pessular process; these muscles run up the sides
of the trachea, reaching further than the sterno-tracheales.
Where the trachea is convoluted it sometimes happens
that the extrinsic muscles are quite abnormal in their attach-
ments ; thus in the males of Penelope pileata and Ortalis
albiventris the muscles in question do not enter the thoracic


..
S
.
12
2
.
.
.
.
16:26
ArsTDRIFT
.
AN
/
.
179
VISITAS
NON
.
.
1
binnenmin
3
W
FIG. 143.-SYRINX Of Pavo spicifer.
FRONT VIEW. (AFTER GARROD.)
Fig. 144.—SYRINX Or SAME. BACK
VIEW. (AFTER GARROD.
cavity, but pass close to the carina sterni and are inserted
at the very end of the sternum.
The syrinx of gallinaceous birds has been chiefly studied
by GARROD. From his paper the following account of this
T. On the Conformation of the Thoracic Extremity of the Trachea in the
Class Aves, Pt. 1, The Gallinæ, P. Z. S. 1879, p. 354.'
GALLI
295
::
organ has been mainly drawn. The simplest form of the
syrinx is seen in the peacock (fig. 143), where the modification
of rings at the bifurcation is of the slightest. The last two
tracheal rings are partly fused behind. The accompanying
series of illustrations (figs.143–147) show some of the princi-
pal forms of syrinx among the Alectoropodes, in which it will


X
19
Mali
OS
+.
IN Ant.
I
-
RE-
.
.
u
SIN
UM
re
I
.
M
.
hot
07
INNUNNI
.
/
HID17
.
INTU11
S
2
!
!
lll.
-
V
Fig. 145.-SYRINX OF Callipepla califor-
nica. FRONT VIEW. (AFTER GARROD.) S
Fig. 146.- SYRINX or SAME. BACK
V IEW. (AFTER GARROD.)
be noticed that intrinsic muscles are but occasionally present.
When present they do not descend to the bronchi, but cease
upon the trachea some way in front of the bifurcation. The
most remarkable modification of the intrinsic muscles is in
Callipepla californica (figs. 145, 146), where the muscles
descend the trachea posteriorly, and are inserted on to the
found, and will be described (see below), in the condor. It is
uncertain whether these muscles may be not more accurately
296
STRUCTURE AND CLASSIFICATION OF BIRDS
referred to the cleido-tracheal extrinsic pair (see below). A
very singular syrinx is that of the male Tetrao tetrix (fig. 147).
On each side of the trachea at the lower end is an immense
irregular tumefaction, connected with its fellow by a bridge
of fatty tissue.' It appears to be mucous in its chemical
nature; but it may possibly have some relation to the tracheal

LOTUTA
N
UMIT ArnTAART
Aurinn URTAN somrNRADA
-
Poplardnanciering memors
.
WIN
Y
S
S
Herman Won HINNOIN TULEE VW
INDUTTIMET TYLDENDUS
l
more
tillit
NR
on
UMANE
LOITATCAVEO
Mi
..
RAN
litt
We
WILL
MUS
St.
UTANO
ZA
WAKA
NISEMINE
.
CA
GUD
SEE
2
762
.
INI
WWW
UN
11111
.
.
2013
!
DAT
..
TIN
.
AC
in
Wer
•
tu
TH
mm
**
BLY!
3
LA QUE
a
ROAD TAX
11
.
-
.
A
S
NUV
WAKIL
$
.
H
.
1
SS
11.11
MNR
Kuracie
Se
.
14
A
Miti
.
St
from
ZALUUAST
MSAUERIE
Opni
Fig. 147.- SYRINX OF MALE Tetrao tetrix. FRONT VIEW.
(AFTER GARROD.)
box of the male ducks, and be thus another of those many
unexpected resemblances between the two groups.
The Cracidæ (fig. 148) generally possess the intrinsic mus-
cles, which are, however, short, as in the other Galli. The
syrinx itself has no salient characters by which it may be
distinguished from the Alectoropodes.
GARROD 1 has also described and figured (fig. 150) the
syrinx of the megapode Megacephalon maleo. It is rather
1. On the Anatomy of the Maleo,' P. Z. S. 1878, p. 629.
GALLI
297
peculiar in form, but has a pair of intrinsic muscles, which
reach the first bronchial semi-ring ; in this point the syrinx
is more primitive than that of other Galli.


T
.
S
til
LX
ni
*.
.
Ar
ON
.
SR
*
int
PWL
11
X
SCIEL
ONS
TEAM
67
.
11
ZAS
.
Vio
IIIIII
liliul
G
2
10
URU
*
DOMINIR
WY
LAOUI
PAWAN
YkW
.
.
WINNIN
YA
11.11
.
ENTRU
IND
S
di
17 //
ZUIA
VI
WWW
11
IT
.
.
WW
.
SIE
ICELUPAI
11
-
WR
17
allur
NU
UNITAT
W
11
FIG. 148.-SYRINX OF Aburricu carun
culata. FRONT VIEW. (AFTER GARROD.)
Fig. 149.-SYRINX OF SAME. BACK
VIEW. (ATTER GARROD.)
The skull in gallinaceous birds is in many respects
remarkably duck-like. The basipterygoid processes—a little,
ES
SI
//
M


IM/
TE
1
Yr
ESLUI
X
'
.
..
BUS
.
.
.
..
.
.
.
V
V
IV
i
W
.
TV
WW
..
Y
B
FIG. 150.-SYRINX OF Megacephalon maleo. A. FRONT VIEW.
B. BACK VIEW. (AFTER GARROD.)
but not much, more pronounced in the Mega podes—are oval
sessile structures, with which again, as in the ducks, the ptery-
As pointed out by Parker.
298. STRUCTURE AND CLASSIFICATION OF BIRDS
goids articulate by their anterior ends. The palatines too are
devoid of an internal lamina, and the angle of the mandible is
recurved and produced ; it is enormous, extended upwards, in
Tetrao.
In the typical gallinaceous birds the maxillo-palatines
are generally small or even obsolescent. In Gallus bankival
they are triangular plates of fair size; in Tetrao urogallus
(fig. 152) they are small, narrow, backwardly projecting
plates, not quite so long and thin, and not so curved as those
of Talegalla. In Ptilopachys they are somewhat inter-
mediate; in Callipepla californica they are still longer. In
Numida and Meleagris they are much the same.
The lacrymals are not large, and have a feeble or aborted
descending process. It is very general for the post-frontal
and zygomatic processes to fuse and enclose a more or less
triangular foramen, and sometimes, as in Tetrao3 and Crosso-
ptilon, the zygomatic bar extends forwards a considerable
way in front of its junction with the other.
The interorbital septum is sometimes (Coturnix, Calli-
pepla, Perdicula, Ptilopachys) considerably fenestrated.
The vomer, in gallinaceous birds generally, is thin and
splint-like.
As to the Megapodes, there are some differences in the
skulls of the two genera Talegalla" and Megacephalon. The
latter has the well-known hammer-shaped projection of the
back part of the skull. In both genera the palatines are
slender, and there is some ossification of the nasal septum.
The interorbital septum is not much fenestrate, but it is
deficient in front. In Talegalla the maxillo-palatines are thin
22
V
I
SHUFELDT, 'Observations upon the Morphology of Gallus bankira,' &c.
Journ. Comp. Med. Surg. ix. p. 343.
? Wood-MASON has described (Ani. Mig. Nat. Hist. xvi. 1875, p. 145) supra-
orbital bones in certain partridges. Cf. as to this point Tinamous, Psophia,
and Menuru..
3 SHUFELDT, 'Osteology of the N. American Tetraonidæ,' Bull. U. S. Geol.
Surv. vi. p. 309.
The skeleton of this bird is described by PARKER, 'On the Osteology of
Gallinaceous Birds and Tinamous,' Tr. Z. S. V. p. 160. See also W. K.
PARKER, 'On the Structure and Development of the Skull of the Common
Fowl,' Phil. Trans. 1870, p. 159. . . .
GALLI
299
II
plates, ending in a curved point very much like those of some
passerines (e.g. Pteroptochus). Each is vacuolate posteriorly
in Talegalla. They do not nearly come into contact in the
middle line. In Megacephalon these bones are spongy plates,
which do nearly come into contact; the palatines, slender in
both birds, are more bowed in Talegalla, and thus enclose a
wider interpalatine vacuity. The lacrymals of Talegalla are
small and ankylosed to the skull wall; the ectethmoids are thin
plates. A curious difference in the skulls of these two birds
concerns the nasals and premaxillaries. In Megacephalon
there is nothing worthy of special remark except the tumid
outer part of the nasals; in Talegalla the premaxillary pro-
cess of the nasals approach each other in the middle line,
and cut the nasal process of the premaxillary into two, an
anterior and a posterior portion.
In the Cracidæ the maxillo-palatines are largish plates,
concave inferiorly and convex above, which in Crax globicera
actually come in contact for a short space, and fuse with
each other and with the median septum. In Pauxi galeata
this fusion (perhaps owing to the great casque) is even better
marked. There is nearly a fusion in Aburria carunculata ;
in Ortalis albiventris, on the other hand, the maxillo-
palatines are well apart.
In Ortalis and Aburria there is no ossification of the
nasal septum; in Crax there is a median piece, which expands
below to become attached to (C. Sclateri) or fused with
(C. globicera) the maxillo-palatines. In Pauxi galeata the
nasal septum, as might be expected, is quite complete and
very strong.
There are also in this group of gallinaceous birds a series
of stages in the development of the zygoma and the post-
orbital processes. In Ortalis they are short; in Aburria
longer and convergent; in Crax Sclateri and Pauzi galeata
they meet distally, and enclose a triangular foramen; finally
in Crax globicera they are completely fused throughout, and
form a stout triangular process.
The lacrymals in this family are large, with a large
descending process. The ectethmoids are but slightly ossified.
1
vu
300
STRUCTURE AND CLASSIFICATION OF BIRDS
The interorbital septum is more fenestrate than in the Mega-
podes, but still not markedly so.
The Galli have sixteen cervical vertebræ. In Gallus
bankiva the catapophyses of vertebra 10 nearly enclose a
canal; on the next vertebra the two processes have almost
fused into a single one, the two processes being closely
W

p
IT
H
.
y
NAN
imbellon.
VW
Hibri
+
C
T
.
...
NINI
BUS
07
UN
*
Lite'
Vi
111
.
.
lea
SAWIT
S
.
r.
YA
.
As
W127.
I
.
.
DIV
LO
litli
.
NINAY
H
TIN
I
WSD
VA
!
UNUM
SININ
43x44
KYSS.
N
.
P7122
ZA
UN
Mii
SS
HOT
LUXUS
Fig. 151.--SKULL OF Craz globicerc. SIDE VIEW. (AFTER HUXLEY.)
Pm.2*, premaxilla ; S, nasal septum.
soldered together for their whole length, and not, as is so often
the case, divergent at the end. All the remaining cervical
vertebræ have strong median hæmapophyses, those of the
sixteenth being fused with the two following at their ex-
tremities (cf. Musophaga, p. 285). The last cervical vertebra
and the three anterior dorsals are themselves fused.
It will be simpler to compare the vertebræ of Gallus
with those of some other Galli by means of the following
table :-
1
First Hæm-
apopli.
! Vertebra
Last Hæm. | Hæm. fused.
fused
D4
D3
----
D2
Crossoptilon inarrtchuricuin
Numida cristata
Talegalla Lathami .
Megacephalor maleo.
Callipepla californica
Ptilopachys ventralis
Aburria carunculata .
C11
C11
011
C101
C13
C11
012
Di
C16-D3
C16-D2
C16-D2
C15-D1
C16-D2
D1-D3
D1-D2
C16-D3
C16-D3
C16-03
C15-D2
C16-D3
D1-D3
C16-D3
-.
D2
-. .
Ꭰ8
D3
--
-
.
-
-
-
-
-
+
--
-
-
-
-
-
-
-
-
-
· Bifid at end.
GALLI
301
It is evident that not much of classificatory importance
is deducible from the above facts. HUXLEY has used with
more success the remaining parts of the skeleton.
The gallinaceous birds are divided by HUXLEY into two
main subdivisions, Peristeropodes and Alectoropodes.

l'imr.
DTS

V
L.
..
LE
SEN
.
.
.
*
www
1
-
A.
.
.
C
.
-
5
*
..'
-
SES
4
NA
1.
.
1
22
MCP WIN
*
E
w
222
.
V
W
S
2
ZA
.
to
.
Y
.
.
.
%
N
TA
.
VRY
.
-
CE
.
.
.
AT
KU
ANA
13-14
.
-
52
M
-
*
.
-
.
/
7
I
IN
*
27
POWEVE
111
mex
Fig. 152.-SKULL or Tetrao
urogallus. VENTRAL VIEW.
(AFTER HUXLEY.)
Map, maxillo-palatines; lo, vomer;
r, maxilla; Pl, palatines; Pl. ptery- .
goids; +, basipterygoid facets; Pmil,
Premaxilla.
FIG. 153.-STERNUM Or Crax
globicera (AFTER HUXLEY).
LETTERS AS IN Fig. 72, P.
128, WITH WHICH THIS FIGURE
IS TO BE COMPARED.
LUU
The former contains the Cracidæ and Megapodidæ, the
latter the remaining families.
The Peristeropodes may be thus defined :-
1. Sternum with not very deep inner notches (fig. 153) and
with short obtuse costal processes, the anterior edge of which
is at right angles to the long axis of sternum.
: 2. Hallux on a level with other toes.
302
STRUCTURE AND CLASSIFICATION OF BIRDS
The Alectoropodes in this way :-
1. Sternum with very deep inner notches (fig. 72, p. 128),
and with long costal processes, whose long axis corresponds
with the long axis of sternum.
2. Hallux attached above the level of other toes.
The former group, which undoubtedly, so far as the above
characters are concerned, is the more primitive, consists of
the curassows and the Megapodes, limited respectively to
Central and South America and to Australia and some of the
Indian islands.
These two families are distinguished by HUXLEY mainly
on account of the differing form of the hallux; but there
are other points of dissimilarity, not known at the time when
he wrote. The two families may be thus differentiated :
Cracida
Megapodidæ
1. Hind toe not so long in Hind toe longer in pro-
proportion to rest.
portion.
2. Oil gland feathered. Oil gland nude.
3. Biceps slip never Biceps slip sometimes
present.
present.
4. Two carotids.
Left carotid only.
5. Trachea generally coiled. Trachea always straight.
The Alectoropodes may be readily divided into three
groups, which may be thus differentiated :-
The NUMIDIDÆ.
1. Second metacarpal without backward process.
2. Costal processes outwardly inclined (thus forming
a transition between Alectoropodes and Peris-
teropodes).
The remaining families, which will be distinguished from
each other immediately, agree with each in differing from
the Numididæ in both the points mentioned.
MELEAGRIDÆ.
1. Postacetabulum longer than preacetabulum.
2. Postacetabulum longer than broad.
GALLI
303
3. Furcula weak and straight (viewed laterally), with
straight rod-like hypocleidium.
e
In the remaining gallinaceous birds "the preacetabular
length is greater than the postacetabular (equal in Tetrao
cupido) ; the postacetabular area is broader than it is long ;
the contour of the furcula is curved, with an expanded
hypocleidium. The series of birds which have these cha-
racters may be divided into the galline and the tetraonine
type.
In the former the postacetabular region is only moderately
broad; the hypocleidium is oval in contour; the tarso-
metatarsus is more than half as long as the tibia, and there
are a number of smaller osteological marks.
In the grouse-like birds the postacetabular region is very
broad; the hypocleidium has a triangular form, and the
tarso-metatarsus is not half as long as the tibia. I do not
give HUXLEY'S characters in detail, since he has pointed out
that the two series meet among the partridges and quails, and
cannot thus be sharply marked off.
The Alectoropodes have a range which is related to their
anatomical differences, as have the Peristeropodes. The
Meleagridæ are confined to America, the Numididæ to
Africa, the Phasianidæ to the Oriental region just encroach-
ing upon the Palæarctic, while the Tetraonidæ are Palæarctic
and Nearctic.
The Galli seem to be undoubtedly an ancient group of
birds, a view which is upheld by their points of likeness to
many diverse groups.
That they are an ancient group is also shown by their
quintocubitalism, the primitive character of the gut con-
volutions, the often complete muscle formula, and the
existence of basipterygoid processes. The existence of these
structures has led to their comparison with other groups of
birds. Less weight, however, appears to be due to these
more general points of resemblance than to other slighter
but equally constant similarities. The existence of the
entepicondylo-ulnaris muscle is an example to the point.
304
STRUCTURE AND CLASSIFICATION OF BIRDS
The Galli share this muscle with the Tinami only; and no
one will doubt on other grounds that the gallinaceous birds
and tinamous are distinctly related. It is, however, with
the Anseres that the greatest number of special resemblances
of this character exist. These have been admitted by
HUXLEY and PARKER; and more recently, in one of his
alternative schemes, SEEBOHM united the two groups. In
these two groups the palatines have the peculiar character
of wanting the internal lamina, which is at most indicated
by a slight ridge; in both of them the basipterygoid pro-
cesses can hardly be described in those words, as they are
but oval facets for the articulation of the pterygoids. The
two pairs of extrinsic muscles of the syrinx are one of the
strong reasons for uniting the Anseres and the Palamedeæ, and
we have among the Galli forms in which there are the same
extra pair of muscles present. The general habit of a
gallinaceous bird is, it is true, somewhat remote from that
of an anserine bird; but Palamedec might with truth be
described as a goose-like bird with external likeness to a
curassow, or as a gallinaceous bird which had put on the
characters of the Anseres. Its likeness to both is considered
on another page.
The existing genera Tetrao, Lagopus, and Francolinus are
known from Pleistocene deposits in countries which they at
present inhabit, and the species from which these few remains
have been described are existing species. Similarly Coturnix
Novce Zcalandice and Talegalla Lathami have been met with in
the Pleistocene of Australia and New Zealand, both of them being
species now living in the localities whence their fossil remains
have been extracted. Phasianus is represented by a number of
extinct species from Europe as old as the Miocene. Three totally
extinct genera described by MILNE-EDWARDS are Palæortyx,
Palæoperdix, and Taoperdix. These are all Eocene or Miocene
and European. Taoperdix presents affinities to Meleagris and
Numida.
COLUMBÆ
305
COLUMBÆ1
Definition.—Aftershaft absent. Oil gland absent or nude. Crop
present. Cæca nipples. Syrinx with asymmetrical extrinsic
muscles. Of the leg muscles ABX always present; deep plantar
tendons of type I. Biceps slip present and peculiar in form.
Skull schizognathous, schizorhinal. Basipterygoid processes
present, except in Didus.
LU
This group of birds contains something like 458 species,
which are divided into sixty-eight genera. Pigeons are cos-
mopolitan in range, and show a considerable amount of
structural variation.
The absence of an aftershaft and the often rudimentary
condition of the oil gland are among the most important
variable external characteristics of the pigeons. The latter
is never feathered, and is sometimes totally absent. But its
presence or absence cannot be made use of as a fact of great
systematic importance; for we find in the same genus
Ptilopus two species, Pt. coronulatus and Pt. superbus, with
a minute oil gland, and two others, Pt. assimilis and Pt.
puella, from which the gland has entirely disappeared.
The rectrices vary in number from 12 (e.g. Columnbula)
through 14 (e.g. Phaps), 16 (Goura), to 20 (Otidiphaps).
But the variations do not invariably coincide with the limits
of genera. Phaps chalcoptera has 16 rectrices, P. elegans
only 14. Phloganas Stairi has 12 rectrices, P. cruentata 14.
There are other examples. Though for the most part
aquincubital, it is remarkable to find in Columbula a quinto-
cubital bird (MITCHELL).
I have by me a careful manuscript account of the pterylosis
of Didunculus by Mr. FORBES. The dorsal tract is strong
and broad upon the neck, narrowing a little below; where
it narrows it becomes stronger. Below the shoulder it bifur-
cates and becomes suddenly weak; below this point the whole
dorsal region is covered with a weak and diffused feathering,
which is especially weak over the head of the femur. In the
I C. J. TEMMINCK, Histoire Naturelle Générale des Pigeons et cies Gallinacées.
Amsterdam et Paris, 1813-1815:
n
306
STRUCTURE AND CLASSIFICATION OF BIRDS
middle line posteriorly the dorsal tract is again strongish.
The lumbar region is also strongly feathered, and the thigh is
covered by a strong tract which ends very abruptly below.
The ventral tract is much weaker, and on the neck
gradually merges into the lateral space which extends from
a short way below the head to the shoulder. Below this the
ventral tract is still weaker, and does not bifurcate until the
upper end of the carina sterni: The median apterion is
oblong and narrow, and reaches the cloacal aperture. In
the abdominal region the two tracts get stronger. The
pterylosis of Columba livia as figured by Nitzsch hardly


VW
C
AINK
144
.
THI

WWW
ES
/
M
'
Rid,
.
11
VILA
!
?
* Nuwun
.
.
.
AV11
TANTE 12WIN100
will
n
IIIIII
NEWER
.
1
1DIN VS
.
.
UNT
WIDY
II
.
IWI
.
77
.
MAX
.
01.11
:
.
31.
WI
ASCA
.
ullu
i
tir
-
-
-
LI
montes,
IN
IV.
-
12
Sili
muLuniin
WON
BE
2
WWW
.
D
VIA.
Ingyou
GY
SAS
UUM
MRVM
SODAS
SASA
1
RISTO
111mmontare
.
Man
***
23
WIT
IN
..
.
FIG. 154.-HORIZONTAL SECTIONS OF FIG. 155.-C, GIZZARD OF Carpophaga
GIZZARDS OF, al, Ptilopus jambi, latrails. b, ONE OF HORNY TUBER-
6, Treron calva (AFTER GARROD). CLES IN SECTION. (AITER GARROD.)
differs, and is typical of the pigeons in general; there is no
down.
All pigeons have a well-developed crop, the presence of
which organ is presumably related to their fruit- and grain-
eating mode of life.
In Carpophaga, a fruit-eating pigeon, the gizzard is very
weak; but in other pigeons this organ is very strong, its
walls being even ossified in Calcenas nicobarica. In Ptilopus
a cross section of the gizzard has the peculiar form shown
in the accompanying drawing, where it is compared with a
L
L
VU
I VERREAUX and DES Murs describe an exaggeration like this in Plicenornina
goliath, where also the tubercles are ossified (Rev. Mag. Zool. 1862, p. 138).
See also FlowER, · On the Structure of the Gizzard of the Nicobar Pigeon,'
P.Z. S. 1860, p. 330.
COLUMBÆ
307
A
1
pigeon showing a more normal state of affairs. There are
four muscular pads in its walls, so that in transverse sections
the lumen is cruciform. In Ptilopus coronulatus the lumen
of the gizzard is not regularly cruciform, like Pt. jambu,
but irregular and asterisk-shaped; so with Pt. superbus.
Chrysana viridis has also a ptilopine gizzard. In Carpo-
phaga paulina the transverse section shows a close approach
in the structure of its gizzard to that of Ptilopus. In C.
latrans (fig. 155) the gizzard is lined with extraordinary
conical horny processes. The right lobe of the liver is
larger than the left, and
the gall bladder may be
absent or present.
* In the Columbæ
which I have examined
(Columbæ of several
species (fig. 156), Phlo-
gænas cruentata),' re-
marks Mr. MITCHELL,
it is tempting to regard
the gut as a simple deri-
vative of the type seen
in Pterocles. The duo-
denum is longer and
narrower. The circular
loop is enormously ex-
FIG. 156.-INTESTINES OF Columba livia
panded, but the three
(AFTER MITCHELL).
subsidiary loops seen
in Pterocles remain. The first of these is somewhat shortened ;
the second, that bearing the yolk-sac vestige at its end, is
enormously lengthened ; the mesentery is folded along the
line of the median mesenteric vessel, so that the two limbs.
of the loop are brought in contact with each other, and,
finally, the whole folded loop is rolled into a rough spiral.
The third subsidiary loop of the circular part of the gut has

IV
.
........
.::
::
IR. GERMAIN, 'Note sur la Structure du Gésier chez le Pigeon Nicobar,' A12.
Sci. Nat. (5), iii. p. 352 ; GARRON, “Note on the Gizzard and other Organs of
Carpophaga latrans,' P. Z. S. 1878, p. 10%.
x 2
308
STRUCTURE AND CLASSIFICATION OF BIRDS
.
the same arrangement and veins as in Pterocles; but the
cæca no longer run along it, but occur as very short stumps
upon the rectum.'
The.cæca are small and nipple-like; they may be entirely
absent. In Tympanistria bicolor I found one, an especially
minute one, on the left side.
The intestines of the Columbæ are very short and volu-
minous in some of the fruit-eating forms, moderately long in
the majority of forms, and extraordinarily long in Didiin-
culus. The following are a few measurements :-
Ft. Ins.
Ft. Ins.
Carpophaga cenea .16 Chrysana viridis . 7
Chalcophaps chryso-
Macropygia lepto-
chlora . . .1 81 granmica . . 2 101
Phlogænas Stairi . 2 6 Peristera Geoffroyi 10
cruentata 2 41 Iantheenais leuco
Columba maculosa . 2 8 læma . . 3 11
Geopelia cuneata.
Goura coronata . 5 1
humilis . 1
, Victorice : 4 0
Ptilopus jambu .10 Phaps chalchoptera 26
, melanoce-
elegans .1 104
phalus . . 9 Didunculis strigi-
Ptilopus coronulatus 611 rostris . .7 0
In Goura Victorie the tensor brevis muscle is bordered
on the patagial side for the last half of its course by a strong
tendon, which arises from the pectoralis muscle. Below this
tendon forms the outer and stronger part of a thin and
rather wide tendon, in which the muscle itself ends. A
wristward slip is given off, but there is no patagial fan. The
biceps slip arises tendinously froin the biceps, has a short
muscular belly, and ends tendinously upon tensor patagii
longus tendon.
Goura coronata is much the same, but the biceps slip is
(? exceptionally) digastric, a second tendon springing from
tensor patagii longus muscle, and becoming muscular before
it joins the muscular belly derived from biceps itself.
In other pigeons-and this is one of the most salient
COLUMBÆ
309
features of the group—the tensor brevis muscle is often very
extensive-in fact, overlapping the extensors of the fore arm.
This is the case, for instance, with Geophaps scripta, where
I could find no deltoid beneath it. In Ptilopus and Phaps,
on the other hand, a good deltoid is present, and though mainly
attached to the humerus is also at its extremity inserted on
to tendon of tensor brevis. This latter insertion is wanting
in many pigeons which have a long deltoid. In Erythionas
the deltoid reaches nearly to elbow. There is very often a
wristward slip from tendon of tensor patagii brevis, but never,
so far as I have ascertained, a patagial fan.
The biceps slip appears to be always an independent.
muscle, arising, as described above, by a thin tendon from
the biceps, and it frequently has a second tendon of origin,
as in Goura coronata. This is the case, for example, with
Carpophaga, Didunculus, and Phaps. It is absent in
Erythrænas.
The expansor secundariorumn is very constantly present;
but there are indications that it is on the wane in these birds.
In Phlogenas cruentata the tendon has not the characteristic
T-shape that it has in other pigeons, but blends with a trian-
gular fibrous slip arising from the scapula near the scapulo-
coracoid joint. In Carpophaga paulina there is much the
same arrangement. In Phlog@nas Stairi the muscle appears.
to be totally absent.
Of the two latissimi dorsi muscles the posterior is some-
times wanting in pigeons.) HASWELL ? first directed attention
to this point, which was denied by GADOW 3 and FORBES,
but reaffirmed by FÜRBRINGER. According to the last-men-
tioned observer its occasional absence is a matter of individual
variation.
The anconcus has a tendinous insertion on to the
humerus.
1 And also (? occasionally) in Otis, Pterocles, and various passerines, according
to FÜRBRINGER.
?• The Myological Characters of the Columbidæ,' Proc. Lini. Soc. N. S. W..
iv. 1880, p. 303 ; 'Note on the Anatomy of Two Rare Genera of Pigeons,' ibid..
vii. 1883, pp. 115, 397.
3 In his memoir upon Pterocles, quoted below, p. 315, footnote.
21
UU
-
-
310
STRUCTURE AND. CLASSIFICATION OF BIRDS
7211
US
The second pectoral is inserted, in an unusual way, on to
the anterior face of the humerus, and not on to the pectoral
ridge, as in other birds.
In the hind limb nearly all pigeons have the complete
formula ABXY, the ambiens being sometimes present and
sometimes absent. Only in Lopholæmus apparently is the
accessory femoro-caudal absent.
The deep flexor tendons are gallinaceous, either blending
or with a vinculum. In Lopholæmus an-
tarcticus and Erythrænas there is a vinculum,
and also a special slip to tendon of digit II.
Considering the variability of so many
muscles and organs among the Columbæ, it
is remarkable to note what slight variations
there are in that, as a rule, rather variable
organ, the syrinx. The accompanying illus-
tration will serve to show the form of the
syrinx among the Columbæ; but in the
species illustrated the origin of the sterno-
Fig. 157.-SYRINX
Carpophaca tracheales is not so highly asymmetrical as
latrans (AFTER is sometimes the case; they occasionally
GARROD).
arise more markedly from the right side of the
trachea. The intrinsic muscles are always present, and
generally attached, as shown in the figure, to the membrane
between the penultimate and antepenultimate tracheal rings.
They are sometimes continued a little further by ligamentous
tissue. The last three tracheal rings are united by median
bony or cartilaginous pieces. Posteriorly the tracheal rings
are weak, or even defective in the middle line. These are
the general characters of the windpipe and syrinx in the
Columbæ. A few of the genera which show some slight
divergencies may now be mentioned. In Calænas nicobarica
the intrinsic muscles are continued by ligament as far as the
penultimate tracheal ring; the first four or five bronchial
semi-rings are connected posteriorly by a cartilaginous bar,
which borders the membrana tympaniformis and is continued
up as far as the sixth tracheal ring from the end of the
series.

OF
COLUMBÆ
311
10
In Goura there is no union posteriorly between succes-
sive tracheal rings, and the last two or three are quite dis-
continuous in the middle line posteriorly.
In Didunculus also the last few tracheal rings do not
meet in the middle line posteriorly.
As to the skull, the pigeons are schizognathous birds with
a slender vomer and basipterygoid processes, absent only in
Didus. They are also schizorhinal, but Goura, like Cursorius,
&c., among the Charadrii, is pseudo-holorhinal. The lacrymal
fuses below with the ectethmoid, and, indeed, forms with it
a nearly solid and often rather massive plate of bone. In
Goura, at any rate, the descending process of the lacrymal
is perforated in front by a largish foramen, as in the Rhea.
Some pigeons-e.g.Lopholæmus—have a median small circular
foramen above the foramen magnum; in Macropygia, &c.,
this becomes a notch upon the upper border of the foramen
magnum. In Goura the foramen is totally absent.
The skull of Didunculus is exceptional. The basiptery-
goid processes are very large. The palatines, instead of
widening out posteriorly, are narrow, solid bars throughout
their whole extent. HUXLEY states that the internal lamina
of these bones is ' altogether obsolete.' I find, however, in
my specimen a pair of small downwardly directed hooks
arising from where the palatines come into contact poste-
riorly, which I take to be the homologues of these structures.
Owing to the shortened and curved bill the bony nostrils are
much reduced in extent. There is no supraoccipital foramen.
There is, as in gallinaceous birds, a fusion between the post-
frontal process and the zygoma.
There are 15 cervical vertebræ in Goura, Carpophaga, &c.,
14 in Columba, Phaps,&c. Vertebræ 15-17 appear to be nearly
always ankylosed. The atlas is notched for the odontoid pro-
cess. The hypapophyses begin in Goura upon the eleventh
cervical and end upon the first dorsal. Four ribs reach the
sternum in Goura Victoria, of which the three first bear
uncinate processes. Only three reach the sternum in some
Fide Newton and GADOW (loc. cit. on p. 314). In Leucosarcia picata I
found four fused, and in Geotrygon violacea only two.
312
STRUCTURE AND CLASSIFICATION OF BIRDS
pigeons. The sternum has both spina externa and interna; it
has two pairs of notches (Gourci), or one pair of notches and
one pair of foramina (Phaps, Carpophaga).
The furcula is U-shaped without hypocleidium. The
coracoids may meet, but they do not overlap.
The following table gives the variations of the principal
variable organs in a number of genera :--

Ambiens Cæca
i
Oil í Gall
Gland Bladder;
Distribution
-
.
--
--
+ + +
.
Columba
Turtur .
Leptoptila
Macropygia
-
.
.
.
+ + + +
-
.
-
-
+
.
-
...
-
-
.
- -
+ +
-
-
+ + +
.
-
.
-
Ectopistes
Ianthanas .
Chamæpelia.
Geotrygon .
Metriopelia :
Peristera
Zenaida .
Zenaidura
Calanas
+ + +
+ + + + + + ooooooo o
.
+ + +
.
.
.
+ + + +
+ + +
.
.
.
+ +
+ +
.
11
.
+ +
.
.
.
+ + +
Chalcopelia .
Chalcophaps ·
Tympanistria .
Ocyphaps ..
Leucosarcia .
Phaps .
Didunculus
Carpophaga .
Ptilopus. .
Erythrænas.
Lopholæmus.
Treron . .
tot + oH +
o
Cosmopolitan
Old World
South America
Australia, East
Indies
North America :
Japan, Fiji, Samoa
America
South America
South America
South America
America
North America
New Guinea,
Cbina, Nicobar
Africa
Australia, East
Indies
Africa
Australia
Australia
| Australia
Samoa
East Indies, Pacific
Islands
Australia, Fiji,
· Celebes
Madagascar
Australia
India, East Indies,
Africa, Mada-
gascar, Celebes,
New Guinea
New Guinea
South Africa
Australia, East
Indies
America
East Indies
| America
Celebes, Timor
! Fiji
.
.
+
.
0
o
.
Oto
Oto
.
O+
.
--
-
.
-
Goura .
Ena . .
Geopelia .
.
.
-
-
-
-
vot to tto.
ooo ooo
-
--
-
Ottoo ooo
---
2.
-
Starnanas
Phlogenas
Columbula
Turaccena
Chrysana
-
-
-
-
-
-
?
+
-
-
COLUMBÆ
313
GARROD included with the Columbæ Pterocles, which I
treat of separately. Accordingly, in quoting his classification
of the group,' I term families what he termed subfamilies.
For him the group contained two families, viz. Columbidæ
and Pteroclidæ. The following is, with the alterations
referred to, GARROD's scheme of division of the group :-
Family I. Columbidæ. Columbæ with ambiens, cæca, oil
gland, no gall bladder, and 12 rectrices.
Genera: Columba, Turtur, Macropygia, Ectopistes,
Leptoptila, Ianthenas.
Family II. Phapidæ. Columbæ with ambiens and no
сеса.
Division A. Oil gland present, no gall bladder.
Genera : Chamæpelia.
Metriopelia.
Zenaida, Zenaidura.
Geotrygon.
Peristera.
Calonas.
Chalcopelia.
Tympanistrici.
Ocyphaps.
Leucosarcia.
Phaps.
Division B. The oil gland and gall bladder present.
Genus Carpophaga.
Division C. The accessory femoro-caudal absent; oil
: gland and gall bladder present.
Genus Lopholæmus.
Division D. Oil gland and gall bladder absent.
Genus Didunculus.
Family III. Treronidæ. Columba without ambiens.
Division A. With cæca and oil gland; no gall bladder.
Genus Phlogænas.
1.On some Points in the Anatomy of the Columbæ,' P. Z. S. 1874, p. 249,
and · Notes on Two Pigeons,' &c., ibid. 1875, p. 367.
314
STRUCTURE AND CLASSIFICATION OF BIRDS
MIN
Division B. With cæca, no gall bladder, no oil gland.
Genus Starnenas.
Division C. With oil gland, without gall bladder and
cæca.
Genera Geopelia, Ena.
Division D. Without oil gland (or rudimentary) and
cæca; tarsi scutellate.
Genera Treron, Ptilopus, Erythrænas.
Division E. With cæca, oil gland, and gall bladder ;
tarsi reticulate.
Genus Goura..
To these must in any case be added another family to
include the flightless dodo (Didus) and the equally flightless
solitaire (Pezophaps), the former from Mauritius, the latter
from Rodriguez,
The dodo at the time of its description by Messrs.
STRICKLAND and MELVILLE 2 was only very imperfectly
known. Subsequently OWEN' gave an account of and figured
the greater part of the skeleton. Later still Sir E. NEWTON
and GADOW 4 supplemented this account by further details,
and published a figure of the first correctly restored and
properly mounted skeleton. There are naturally many
other notices of this much-written about bird.
The skull has the median supra-occipital foramen of
some pigeons, but not the basipterygoid processes. The
nostrils are schizorhinal. The palatines have, contrary to
what is found in Didunculus, with which Sir R. OWEN
specially compares Didus, an internal lamina. Neither do
the postfrontal process and zygoma meet and fuse, as they
do in Didunculis. The interorbital septum is thick and
complete.
There are 15 cervical vertebræ, and the atlas is notched for
the odontoid process. The last cervical and first two dorsals
A. and E. NEWTON, 'On the Osteology of the Solitaire,' &c., Phil. Trans.
1869, p. 327; E. NEWTON and J. W. CLARK, “On the Osteology of the Solitaire
(Pezopraps solitarius),' ibid. vol. clxviii. 1879, p. 438.
? The Dodo and its Kindred. London, 1848.
3. On the Osteology of the Dodo,' Tr. Zool. Soc. vi. p. 49.
1.On Additional Bones of the Dodo,' &c., ibid. xiii. p. 281.
COLUMBÆ
315
are fused. Four ribs reach the sternum, of which the last
belongs, as in Pezophaps only, to the first pelvic vertebra.
The scapula and coracoid are, as in the Ratites,' ankylosed,
and the angle between them approximates to that of the
Ratites in its wideness.
The sternum has a fair keel, neither spina interna nor
externa, and the coracoids do not nearly meet. The clavicles
have no hypocleidium.
I discuss the affinities of the Columbæ under Pterocletes..
PTEROCLETES 2
Definition.--Aftershaft small; aquincubital. Oil gland nude. A crop
present. Cæca long. Muscle formula of leg, ABXY +. Biceps
slip and expansor secundariorum present; plantar tendons of
type IV. Skull schizognathous, holorhinal, with basipterygoid
processes. Both carotids present.
This group contains but two genera, Pterocles and Syr-
rhaptes, both of which are Old-World in range. Pterocles is
more widely spread than Syrrhaptes, extending southwards
to Africa and Madagascar. Syrrhaptes is confined to Central
Asia. These birds have a pigeon-like aspect, though NEWTON
has pointed out that Syrrhaptes has a plover-like flight.
The feet are peculiar for the feathering, which extends to
the claws; and in Syrrhaptes the three toes (the first is
altogether aborted) are encased in a common 'podotheca,'
which presents the appearance of 'a fingerless glove.' This
is not the case with Pterocles, which, moreover, has the first
toe. The sand grouse have a small aftershaft and a nude
oil gland. The rectrices vary in number from fourteen to
eighteen. Contrary to what is found in the pigeons the
newly hatched sand grouse is covered with down, and in the
I MOSELEY (On the Structure and Arrangement of the Feathers in the Dodo,
Rep. Brit. Ass. for 1884, p. 782) notes that the feathers are disposed in threes,
a feature which is, he says, apparent in pictures of the bird.
2 M. BOGDANOW, ‘Bemerkungen über die Gruppe der Pterocliden,' Bull. Soc.
Imp. St. Petersb. xxvii. 1881, p. 164; H. Gadow, 'On some points in the
Anatomy of Pterocles,' &c., P. 2. S. 1882, p. 312; D. G. ELLIOT, 'A Study of
the Pteroclidæ, or Family of the Sand Grouse,' ibid. 1878, p. 233.
316
STRUCTURE AND CLASSIFICATION OF BIRDS
adult there is down upon the apteria. The pterylosis, as
figured by NITZSCH, is almost exactly like that of the pigeons,
but there are no neck spaces. The beak has no soft 'cere,
such as exists among the pigeons.
GADOW has contrasted the crop of the sand grouse with
that of the pigeon. In the former it is a simple dilatation of
the anterior and lateral walls of the æsophagus, without any
constriction in the middle line. In the pigeons, on the other
hand, the crop consists of two symmetrical swellings of the
æsophagus, between wliich is continued the esophagus. The
intestinal coils have, according to MITCHELL, an extremely
primitive character.' The resemblance to the intestine of the
pigeons is great. The Pterocletes differ from the pigeons
in the large size of the caca. The lining of the cæca is
marked by about six longitudinal folds, according to GADOW,
but according to PARKER no less than twelve. In Pterocles
the right lobe of the liver is about three times the size of the
left. A gall bladder is always present. Figs. 17 and 18
(p. 33) show some variations in the positions of the liver and
pancreatic ducts in the sand grouse, which are taken from
GADOW's paper upon the anatomy of this group.
The syrinx (of Pterocles) is not in the least like that of
the Columbæ. The extrinsic muscles are perfectly symmetri-
cal, and the intrinsic muscles are enormously developed. The
ordinary pair present in the Columbæ are attached to what I
regard as the first bronchial semi-ring, and are not specially
large ; the second pair' are only visible on the posterior
aspect of the windpipe; they are two large fusiform muscles
which are inserted in common into the middle line of the
trachea, near to its termination.
The muscles of the hind limb have been described in some
detail by GADOW.
The muscle formula is complete, being thus expressible,
on GARROD's notation, by the letters ABXY+. There is
only one peroneal, the longus, which has the usual attach-
ments to the ankle and to the flexor perforatus.
UVC
| Pterocles arenarius; it appears that P. alchata has not the second larger
pair.
PTEROCLETES
317
The deep flexor tendons fuse at the ankle, but no branch
is given off to the small hallux ; this digit has, however, a
special flexor hallucis brevis. GADOW concludes his survey
of the muscles of the bird with the following remarks : Of
all the other muscles of the leg (excluding ambiens, peroneus,
and absent flexor hallucis slip) there is none that shows any
practical difference between sand grouse, pigeons, and even
(if we include them in our comparison) the plovers. On the
whole, however, the myology of Pterocles indicates that it is
more nearly allied to the pigeons than to any other group of
birds.'
The general aspect of the skull of Pterocles arenarius is
much like that of a similarly sized pigeon. The nostrils,
however, are more distinctly holorhinal, thus leading towards
the gallinaceous birds. They end on a level with the ends of
the nasal processes of the premaxillaries, and do not narrow
at all at their broadly rounded terminations. As is the case
with Gorra, Opisthocorus (a fact of possible importance), and.
some other holorhinal birds, a plate of bone underlies the ex-
tremity of the nostrils, reducing the extent of the orifices.
As in pigeons the ectethmoids are very solid plates of bone
which fuse with the lacrymals, and nearly reach the jugal
bar; only the minutest foramen perforates this plate above.
Syrrhaptes ' agrees so far with Pterocles, but has a rather
more vacuolated interorbital septum.
The post-orbital and post-frontal processes are long, and
nearly (Pterocles) or quite (Syrrhaptes) fuse at their extremi-
ties, as in some gallinaceous birds.
The maxillo-palatines are not like those of pigeons; they
are, as in gallinaceous birds, slender curved hooks.
The basipterygoid processes are well developed.
There are fifteen or sixteen cervical vertebræ.
In almost all those respects, remarked HUXLEY,' in which
the grouse differ from the fowls they approach the pigeons; and
an absolute transition between these groups is effected by the
Pteroclidæ, whose popular name of “sand grouse” might fitly
See PARKER, 'On the Osteology of Gallinaceous Birds,' &c., Trans. Zool.
Soc. vol. v.
On
318
STRUCTURE AND CLASSIFICATION OF BIRDS
I CU
be exchanged for that of “pigeon grouse."! There is, in my
opinion, much to be said for this view, which, however, is
not now so generally held. HUXLEY's view was based
almost exclusively upon osteological characters, with but
slight reference to the anatomy of the soft parts, which were
indeed—when he wrote (in 1868)—scarcely known. The
several regions of the vertebral column in the sand grouse
have the same number of vertebræ as in the 'Alectoromor-
phæ,' and ankylosis takes place in the same manner.' The
skull is dove-like for the most part; but in certain ways it
approaches the Galli. For instance, the maxillo-palatines are
alike in both groups of birds ; the union between the squa-
mosal and the post-frontal process is gallinaceous; the
holorhinal nostrils, which I must term those of Pterocles,
indicate a likeness to all the members of the group Galli.
The remainder of the skeleton is, in HUXLEY'S opinion,
peristeromorphous, but the pelvis is partly grouse-like.
Attention may be directed to the likeness of the sand
grouse humerus to that of pigeons. The osteological cha-
racters, however, are not quite so intermediate in some
respects as might be inferred from HUXLEY'S paper. The
at least pseudo-holorhinal' nostrils have their counterpart
among the Limicolæ, in Thinocorus, and in some others (see
below). The solid ectethmoids too are also seen in that
group, while GARROD's remark that the Alcæ have a hu-
merus like that of Columbæ and Pterocles is suggestive in the
light of the unquestionable likeness of the Alcæ for the Limi-
colæ, though the actual weight of this character may be
thought by some to be discounted by the fact that it is met
with in the Psittaci.
Moreover Otis, which is to be placed somewhere near the
Limicolæ, has the gallinaceous union between the squamosal
and the post-frontal process, to which I have referred as
possibly affining the Pterocletes to the Galli. Other characters
too, which appear at first sight to be arguments in favour of
the position taken up by HUXLEY, may be interpreted fairly
as marks of affinity with the Limicolæ (and their immediate
allies). Such are, for example, the long cæca (with folds in
PTEROCLETES
319
the bustards), the crop (present in Thinocorus), the gall
bladder, &c. MITCHELL distinctly places both Pterocletes
and Columbæ in the neighbourhood of the Limicolæ by reason
of the arrangement of the intestinal coils.
It is at any rate clear that the Pterocletes occupy a lower
place than the Columbæ—that they have given rise to the
Columbæ, and not vice versa. The justice of this view is
shown by the long cæca, the existence of an aftershaft, the
equally unmistakable characters. On the whole it seems
not unreasonable to look upon the Pterocletes as not far from
possibly not far again from the primitive gallinaceous stock.
TURNICES
Definition.-Rectrices, twelve. Aftershaft present. Oil gland tufted.
Cæca long. Muscle formula of leg, A(B)XY +. Skull ægitho-
gnathous, schizorhinal, with basipterygoid processes. Cervical
vertebræ, fifteen. Sternum one-notched.
This group of birds consists of the genera Turnix and
Pedionomnus. It has been confounded with the gallinaceous
birds ; but the discovery of PARKER that the skull is ægitho-
gnathous, and further investigations into the structure of
the group-of which the most important is a recent paper
by GADOW 2_have rendered it necessary to remove the two
genera from close association with the Galli.
Of the two genera Turnix (Hemipodius) is European,
African, and Indian in range; Pedionomus is Australian.
Besides the external characters mentioned in the defini-
tion, which are common to both genera, Pedionomus wants
the fifth cubital, which is present in Turnix; there are four
toes in Pedionomus ; Turix has lost the small hallux of
the former genus.
2
/
| LEGGE (P. 2. S. 1869, p. 236), from a consideration of some external cha-
racters and habits, was impressed by possible charadriine affinities of Pedio-
211.
20
11 tue
? "Notes on the Structure of Pedionomus torquatus,' &c., Records Austral.
Mus. i. 1891, p. 205.
320
STRUCTURE AND CLASSIFICATION OF BIRDS
As to the pterylosis, there is a long spinal apterion, which
begins on a level with the shoulder joint and reaches to a
little beyond the level of the hip joint. Thence the two
dorsal tracts are continued on as a single tract to the
feathered oil gland. On the neck below there is no apterion;
the two tracts then divide, leaving a bare interclavicular
space; they divide again on a level with the anterior end of
the carina sterni into a lateral thick patch and a median
thinner one ; this latter swells out in its course and then
again dwindles, being continued to the cloacal aperture by a
few scattered feathers. .
The pectoralis I. (at any rate in T. Sykesi) is two-layered.
The tensor patagii brevis tendon gives off a wristward slip,
but there is no patagial fan.
There is no biceps slip, but the expansor secundariorum
is present (? as to both these structures in Pedionomus).
The muscle formula of the leg is the complete one ABXY+
in Pedionomus ; Turnix has lost the accessory femoro-caudal
for the most part--not, however, in T. Kleinschmidti, where
it is present. It is remarkable that in Pedionomus it is not
B but A which is on the wane.
Both carotids are present in Pedionomus, only the left
in Turniz; but in Pedionomus the left is the weaker and
not the right, as might perhaps have been suspected.
The alimentary canal has no crop, but the upper half
of the desophagus is very dilatable’ in Pedionomus). The
ceca are well developed; the liver in both genera is split
into three nearly equisized lobes. The gall bladder is
present.
The syrinx (of Turnix lepurana) is not at all gallinaceous
in its characters. The tracheal rings are weak and carti-
laginous. The intrinsic muscles are thick and originate in
close contact from the anterior face of the trachea ; they are
inserted some way down the bronchi on to the opposite face
of the tubes. In Hemipodius tachydromus the windpipe is
very soft, and is much dilated in front of the origin of the
intrinsic muscles, which, as in the last species, are large.
Our knowledge of the osteology of the Hemipodes is
LCU
TURNICES
321
12
LI
chiefly due to PARKER, who has described in detail the
entire skeleton of Hemipodius varius, and also the skull of
Turnix rostrata. The atlas is perforated for the odontoid.
There are 15 cervical vertebræ, of which Nos. 10-15 bear
hæmapophyses. None of the dorsals are ankylosed. The
sternum is reached by three or four ribs, and has one pair of
deep lateral incisions cutting off two long thin postero-
lateral processes.
The skull is ægithognathous in its vomer, broad in front,
and double posteriorly, and in the slender hook-like maxillo-
palatines ; the latter, however, are not unlike those of many
gallinaceous birds, while HUXLEY has compared the vomer
with that of Tetrao urogallus. The nostrils are pseudo-
holorhinal, and, as in pigeons, there is a considerable alinasal
ossification, reducing the long nares, which are perfectly
pervious. As is also the case with the pigeons, the ecteth-
moids are large and solid, and have fused with the lacrymals.
There are well-marked basipterygoid processes.
ILU
RALLI
Definition - Aftershaft usually present. Carotids, two. Muscle
formula of leg, ABX(Y) +. Expansor secundariorum always
present. Tensor patagii brevis without recurrent slip to tensor
patagii longus. Cæca long. Skull schizognathous and holo-
rhinal.
The rails are a group of birds of very uniform structure.
They have as a rule a tufted oil gland, but Porzana carolina
is an exception. The aftershaft is present. The rectrices
vary in number from 10 (Aramides cayennensis) through 12
(Porzana carolina) to 14 (Ocydromus Earlei).
The spinal tract encloses a long narrow apterion, which
commences earlier in Rallus aquaticus than in Fulica atra.
The latter bird has almost a gap between the anterior and
posterior parts of the spinal tracts. The pectoral tract of
12
In his papers on the osteology of gallinaceous birds and of the ægitho-
gnathous skull in Zool. Trans. vols. v. ix. X.
322
STRUCTURE AND CLASSIFICATION OF BIRDS
LUUU
each side is double in Rallus and Ocydromus, single in
Fulica.
The following are the intestinal measurements of a series
of species :-
11
12
UUUUU
LU
-
-------------
-
-----
-
---
-
-
Small Int.
Large Int.
. Cæca
-
-
-
--
-
-
-
-
.
-- --..
.
..
Inches
15
-
.. ..
Inches
1.25
Inches
1.5
..
in
.
27
-
-
3.5
2.5
-
.-
-
1.5
0
74
14
6.5
-
..
.
-
-
--
---
-
-
-
---
-
-
-
-----
Rallus aquaticus
Ocydromus sylvestris
0. lefresnayanus .
3.5
O. Earlei . . :
Aramides cayenilcisis
1.5
1.75
Porzana carolina. .
2.251
Crex pratensis . .
Porphyrio madagascariensis
1 Gallinula chloropus .
39
Fulica atrc . .
F. ardesiaca . .
391 3
Tribonyx Mortieri,..
40-5
275 6, 6.75
- : ----
---
The folds of the intestine (fig. 159) are remarkably like
those of the cranes (fig. 158), so much so that on intestinal
characters only the two groups could not be separated.
There is no crop; the proventriculus is zonary ; the
stomach a gizzard.' The right lobe of the liver is larger
than the left, and the gall bladder is always present.
The atlas is notched for the odontoid process ; it has no
lateral canals. The number of cervical vertebræ is 15 in
Fulica ardesiaca, in which there are 7 complete ribs (6 in
Ocydromus). On the eleventh cervical (of Fulica ardesiaca)
the catapophyses nearly unite; the hæmapophyses, up which
the catapophyses do not climb, extend as far as the second
dorsal. The sternum has very long lateral processes, with a
larger or smaller spina externa. The clavicle comes into
near relations with both procoracoid and scapula. In the
skull? there are no basipterygoid processes, and the lacry-
mals (in Fulica, Ocydromus, and Aramides) do not join the
21
VO
UL
LCIUL
1 In Porzana notata the cæca are minute—8 inch in length. Cf. Parride
among Limicolæ.
? C. G. GIEBEL, 'Osteologie der gemeinen Ralle,' &c., Zeitschr. ges. Naturw.
V. (1855), p. 185. SHUFELDT, Osteology of certain Cranes, Rails, and their
Allies,' J. Anat. Phys. 1895, p. 2; and Osteology of Porxana carolina,'
Journ. Comp. Med. Surg. 1888.
RALLI
323
D
ectethmoids, as they do in all charadriiform birds. The
ectethmoids themselves in all rails that I have examined
send a process upwards, which joins the frontal bone and
leaves a foramen for the passage of nerves. The interorbital
septum is widely fenestrate.
The pelvis in the rails has a longer preacetabulum than
postacetabular portion. The ilia are vertical in their plane
anteriorly, and in Tribonyx and Fulica are completely sepa-

PE

TO
S
INI
KIROKRUŽE
mo
LUCT
TYYYYY
Fig. 158.-- INTESTINES OF Cariana
cristata (AFTER MITCHELL).
2, short-circuiting vessel.
Fig. 159.-INTESTINES OF Crex pra-
tensis (AFTER MITCHELL).
.2, as in fig. 158.
rated from each other by the fused neural spines of the
vertebræ. In Aramides and Ocydromus, on the other hand,
the ilia reach the summit of those neural spines. In all
these rails the pubes are fairly strong bones, which are not
ankylosed anywhere with the ischia.
Nearly all the Rallidæ have a biceps slip. Ocydromus
Earlei and Rallus maculatus are the only exceptions known
to me. The tensor brevis is simpler than in many birds ;
in Ocydromus Earlei it consists of only a single tendon. In
Crex, as in most others, this tendon gives off a wristward
slip. In Aramides and Porphyrio martinicus the hinder
branch of the tendon is very feeble, and in the latter does
not reach the fore arm. In no rail is there any distal
LUI
Y 2
324
STRUCTURE AND CLASSIFICATION OF BIRDS
L
patagial fan, a fact justly emphasised by FORBES ? in dis-
criminating from the rails the somewhat rail-like Parra.
In some (e.g. Ocy dromus Earlei, Aramides) the tendon of
the tensor brevis does not run over the arm to the ulnar
side, but in others (e.g. Crex) it does.
The anconcus has a humeral attachment.
FÜRBRINGER figures in Porphyrio an interesting con-
dition of the biceps and of the biceps slip. The biceps slip
arises by a tendinous head close to, but apparently inde-
pendently of, the humeral head of the biceps. Close to the
coracoidal head of the biceps springs a ligament which is
inserted on to the humerus just in front of the origin of the
humeral head. This ligament seems to be a detached
portion of the biceps, since in the Steganopodes (9.v.; cf.
also FÜRBRINGER, pl. xxvi.) it is perfectly continuous with
the biceps.
In the leg both peroneals are present, with the usual
insertions.
The deep flexor tendons are often of No. I. type. But
in Aramides there is a modification of this in the shape
of a second vinculum, attached partly to the tendon just
before its trifurcation and partly to the special tendon of
digit II. In Ocydromus Earlei the second vinculum is also
present, but feebler, not having the second attachment to
the flexor of digit II.
The syrinx in the rails is of a quite typical tracheo-
bronchial form, except for the fact that the intrinsic muscles
are attached rather far down the bronchi-to the fourth
bronchial semi-rings in Ocydromus, Aramides, and some
others. In Ocy dromus sylvestris none of the tracheal rings
are fused; the first two bronchial semi-rings are ossified,
and there is an ossified pessulus. In Aramides the last
three tracheal rings are partly fused; the last two of these
and the first two bronchial semi-rings are ossified; there is
no ossified pessulus. In Fulica (ardesiaca and leucoptera)
the bronchidesmus, which is incomplete, is at first strengthened
I'Notes on the Anatomy and Systematic Position of the Jaçanas,' P. Z. S.
1881, p. 639.
RALLI
325
1
19
l
by two yellow elastic pads of tissue springing from the
membrana tympaniformis.
The genera Heliornis and Podica—the former American,
the latter Old-World in distribution-seem to require a sepa-
rate family for their reception. The structure of these two
birds has been mainly investigated by myself ; 1 the skeleton,
however, has been described by BRANDT also.?
In neither bird is there an aftershaft, though the oil
gland is tufted. Unlike other rails they are quintocubital.
The pterylosis is essentially ralline. In Heliornis the neck
is nearly continuously feathered, there being only a short
vental apterion. The dorsal tract is strong between the
shoulder blades, and is forked; the hinder parts of the tracts
scarcely join the anterior ; they become fused some way
in front of the oil gland. In Podica senegalensis, but not in
Heliornis, the ventral tracts are undivided. The less degree
of specialisation is seen in other features of the anatomy of
the smaller American finfoot.
The muscle formula of the leg in both genera is ABX+,
the Y of the rails not being developed. The chief peculiarity
of the leg muscles, however, concerns the biceps. This is a
very large muscle; in Podica it has no less than three
separate insertions on the leg. First there is the ordinary
insertion through a perfectly normal sling ; just before this
tendon a branch is given off which is inserted independently
on to the leg some way further down. In addition there is
an extensive insertion on to the fascia covering the calf of
the leg. In Heliornis the muscle is somewhat simplified,
only the first and third insertions being present. The
complications of the biceps may have some relation to
swimming; for in certain auks (q.v.) there is a similar
gastrocnenial attachment.
I. On the Anatomy of Podica senegalensis,'P. Z. S. 1890, p. 425 ; 'On the
Osteology, Pterylosis, and Muscular Anatomy of the American Finfoot (Heliornis
surinamensis),' Ibis, 1993, p. 30.
2 Beiträge zur Kenntniss der Naturgeschichte der Vögel,' &C., Mem. Ac.
Sci. St. Petersburg, 1840, p. 81. See also GIEBEL, ‘Zur Naturgeschichte des
surinamischen Wasserhuhns Pocloa surinamensis,' Zeitschr. ges. Naturw. xviii.
1861, p. 424, and NITZSCH's Pterylography.
326
STRUCTURE AND CLASSIFICATION OF BIRDS
The deep flexor tendons of Heliornis are remarkable (see
fig. 160) for the fact that both tendons split into three branches
for the three digits before they unite, the slip to the hallux
being given off from the flexor hallucis previously. The
conditions which characterise Podica are unknown. In the
fore limb some of the muscles are characteristic, and differ
from those of the rails. The patagialis brevis consists in

ET.p
.
.
.
. . .
samt-
54.
LSIA
.
.
.
.
I
FIG. 160.- DEEP FLEXOR TENDONS
OF Heliornis (AFTER BEDDARD).
t, fl. hallucis ; B, il. communis ; 1-4,
slips to digits.
Fig. 161.--PATAGIAL MUSCLES OF
Heliornis (AFTER BEDDARD)
Tp, tensor patagii ; Bi, biceps; Bi.s,
biceps slip; x, tendinous slip.
both of a simple undivided tendon, which has not more than
an indication of a patagial fan. This indication is seen only
in Heliornis (fig. 161) in the shape of an upwardly directed
tendinous slip, to which, a little before its termination,
apparently upon the patagium—a well-developed biceps slip
is attached. In Podica the biceps slip ends freely upon the
patagium. Both these conditions are different from what is
met with in the rails, but are to some extent paralleled
among the grebes. In Podiceps the biceps slip ends freely
upon the patagium, as in Podica. In Æchmophorus (p. 387)
the biceps slip is connected directly with the patagial fan.
The likeness between that bird and Heliornis appears to me
to be unmistakable.
The expansor secundariorum is present, and the anconcus
܂
RALLI
329
is anchored to the humerus. The finfoot agrees with the
divers in the extensive origin of the posterior latissimus dorsi
from the front end of the ilium. The largely tendinous
origin of the rhomboidei appears to point in the same direc-
tion. As to the alimentary viscera, there are long cæca; the
right lobe of the liver is the larger ; a gall bladder is stated
by GIEBEL to be present in Heliornis. I did not find one in
Podica, but the matter doubtless requires re-examination.


LAB
.
FIG. 162.–SYRINX OF Podica
senegalensis (AFTER BEDDARD).
Fig. 163.-STERNUM OF Heliornis.
VENTRAL VIEW. (AFTER BEDDARD.)
The syrinx is typically tracheo-bronchial, and in no way
remarkable.
The osteology of the Heliornithidæ is not very decisive as
to their affinities. In Podica there are seventeen cervical
vertebræ, an advance upon the fifteen of the rails and an
approach to the twenty-one of Podiceps. Six ribs reach the
sternum in both genera of Heliornithidæ. The sternum has
but one pair of notches, and in Podica, at any rate, the spina
externa is well developed. The skull is, on the whole, rail-
like, bearing, perhaps, a greater resemblance to Aramides
than to any other genus of rails. The clavicles, contrary to
what is met with in the rails, reach, and are firmly attached
to, the carina sterni.
The pelvis (fig. 164) of the Heliornithidæ is in some respects
UU
328
STRUCTURE AND CLASSIFICATION OF BIRDS

KIZ
U
1
OST
TI!
ta
IV
W
11
.
**
Illit
NLIMI
2
AN
NON
Je
DIR
Y
L
ENT
If
111WUWU
IIIIIIIIIII
millimit M1
ZO.
a
2017
2.UZ
PTT
.
1
.
S
.!
.
2
RAY
www
w
VY
Nerd
.
HUNDA
A
W
KO
.
.
M
.
.
.
.
.
AL
.
.
..
WOW
.
.
IN
SS
.
..
.
h
ko
..
...
TANITE
-
117
Il
.
.
du
.
IN
.
I
Y
.
Chil
-
VA
.
.
UDHIW
!
..
**
.
****
W
.
..
.
.
.
.
birit
.
.
u
2
.
,
.
.
150
.
.
M
...
.
.
.
.
.
..
.
.
IINA
.
www
13.
.
.
www
.
.
.
.
.
.
where
.
FEC:
.
.
.
SU
W
.
.
S
.
UU
.
.
.
Unis
S
.
w
STO
www
>
.
.
www.
.
.
VILA
TS
ca
1.
.
1
.
w
Ella
III
2
WA
9
VN
11
FIG. 164.–LATERAL VIEW OF VERTEBRAL COLUMN, PELVIS AND STERNUM OF Podica senegalensis (AFTER BEDDARD).
.
NO
w
W
WN
HAT:
VI
W
VM
111111
M
.
MUV
WWW
MM
.
.
!
.
Wh
.
.
Do withili
w
:iflilli
WIRE
.
re
Will
RIVO
RE
WA
.
A
.
ST
RI
VI
WW
SIM
.?
What illetility
.
S
.
.
HULUMISI!!!
SS.
.
.
*.
..
..:
:
-
:
.:.:.
+
1
.
:
.
..
A
:
.
.
.
S
.
-
.
..
-
C
-
.
F
.
..
..
.
.
.
.
.
.
.
.
....
..
.
.
.
SEN
NU
:
:
YL
A
.
YEN
**
Emm
!!
WIRU
!!
ASUN
MWAY
W
III!
C
SO
RU
ZANIA
S
BES
re
.
HINO
SUS
PUT
2111
...
.
1:1
..
www.
.
7
.
P"
SE
.
AN
.
WITH
VIII
**
VISI
CM
'.
SE
SO
...
SA
...
.
".
-
III
.
ws
RALLI
unlike that of the typical rails. As in Fulica, the ilia are
widely separated by the fused neural spines of the dorsal

.
...
..
....
.
.
'.'
A
.
plus
Dib
ilur
SS
!!
.
OA
S
ZI
WA
R:E:)
Fig. 165.-SKULL OF Podica. LATERAL VIEW. (AFTER BEDDARD.)
vertebræ concerned; but the ischia are broader and directed
more downwards (their position is, in fact, more primitive)

www
31
,
I
RE
.
.
4
2:
6.
6
7


CS
TY
1
.
.
1.
*
.
St.
1
.
W
Fig. 166.-SKULL OF Helioris.
VENTRAL AND LATERAL VIEWS.
Fig. 167.-SKULL OF Podica.
VENTRAL VIEW. (AFTER
BEDDARD.)
than in the rails, while the pubes are ankylosed at least at
one point with the ischia.
There are a considerable number of extinct rails, many
of which were flightless, thus showing an exaggeration of a
330
STRUCTURE AND CLASSIFICATION OF BIRDS
IC
1
1
tendency of many existing rails which either do not fly
much or are but feebly fitted for flying.
It is particularly upon small islands that these flightless
rails have been discovered, both living and fossil, and in
islands where loss of flight may be regarded as having been
of less importance as a disadvantage in the struggle for
existence. Thus in New Zealand there was (until recently)
the large Notornis, whose skeleton has been described by T. J.
PARKER. The last living specimen was taken in 1879. From
the Chatham Islands are known Palceolimnas chathamensis
and Nesolimas Dieffenbachii. The skeletons of these rails
have been described by H. O. FORBES,2 MILNE-EDWARDS,3
and ANDREWS; 4 the latter by ANDREWS. Nesolimnas ap-
pears to be not yet extinct; the former species is. Another
form from the Chatham Islands was originally described
under the generic name of Aphanapteryx, and supposed to
be congeneric with A. Broecki of Mauritius. Both of these
birds have been dealt with by MILNE-EDWARDS and ANDREWS.
Diaphorapteryx Hawkinsi was a largish rail, with the keel of
the sternum much reduced, being about half the height of
the keel of the flying Hypotonidia celebensis and slightly
less than that of Ocydromus. The scapula and coracoid
make an exceedingly wide angle, as in all flightless birds-
about 130 degrees. The resemblances of Diaphorapteryx to
Aphanapteryx are set down by ANDREWS and GADOW to
parallelism of development, and not to real affinity.
Palceolimnas chathamensis is not, as was at one time
thought, identical with Fulica Newtoni of Mauritius ; it may,
however, be the same as Fulica prisca of New Zealand.
The bird is much like Fulica in osteological characters, the
principal difference being the large size of the impressions
T'On the Skeleton of Notornis Mantelli,' Tr. N. Zeal. Inst. xiv. (1881), p.
245.
? In Nature, xlv. (1892), p. 416; ibid. p. 580 ; and Ibis, 1893, p. 254.
3. Sur les Ressemblances qui existent entre la Faune,' &c., Anii. Sci. Nat.
(8), ii. 1896, p. 117.
4.On the Extinct Birds of the Chatham Islands,' parts i. and ii.; Novitates
Zool. iii. p. 73 et seq., p. 260 et seq.; and Note on the Skeleton of Diap7101 -
apteryx Hawkinsi, Geol. Mag. 1896, p. 337.
RALLI
331
for the supra-orbital glands. The keel is reduced as com-
pared with living coots, its height being 12 mm. as compared
with 17 mm. and 15 mm. in F. atra and F. cristata. The
wing is short in proportion to the leg, shorter than in F. atra";
but ANDREWS thinks that the bird ‘may still have been
capable of heavy flight for short distances.'
Nesolimnas is a more aberrant form in some particulars.
It may be still living, but the only specimen was obtained in
1840. The most striking feature in the osteology of this
bird appears to be the schizorhinal nostrils, which do not
occur elsewhere in the rails (as defined in the present volume).
The wings are reduced, but the scapula and the coracoid do
not make a wide angle (forty-five as against sixty for Ocy-
dromus).
Of the extinct European rails described by MILNE-EDWARDS,
from the Eocene and Miocene, a number of species have been
described and referred to the genus Rallus. Gypsornis is believed
to be most nearly akin to Aramides.
OTIDES
Definition.--Three-toed birds. Oil gland absent. Aftershaft present.
Aquincubital. Skull schizognathous, holorhinal, without basi-
pterygoid processes. Muscle formula, BXY +. Cæca long. No
biceps slip. Expansor secundariorum present. Syrinx without
intrinsic muscles.
THE bustards are undoubtedly a much-specialised group, not
(in my opinion) distinctly nearer to the charadriiform birds,
where they are placed by FÜRBRINGER, than to the cranes,
with which they are associated by GADOW.
They are distinguished from all their allies by the total
absence of an oil gland. The feathers have an aftershaft.
There are twenty rectrices in Otis and Houbara, sixteen in
Eupodotis Denhami, eighteen in Tetrax.
In both Otis and Tetrax the lateral neck spaces are
reduced to a rudiment on each side close to the shoulder.
The dorsal tract is divided high up on the back of the neck;
the two halves come nearer together, and at the same time
332
STRUCTURE AND CLASSIFICATION OF BIRDS
Van
get broader in the lumbar region; they finally completely
fuse to form a broad and uninterrupted tract.
The ventral tract is undivided in the neck in Otis ; it is
very broad in the pectoral region, where it divides into two
narrow bands, with an indication of a third in the form of a
slightly divergent outer group of particularly strong feathers.
The two pairs of narrow tracts unite round the cloaca.
In Eupodotis australis the dorsal tract is divided high up
on the neck, the ends of the tracts at ends of scapula are
particularly strongly feathered, and the two halves of the
posterior region of the dorsal tract run in anteriorly between
the anterior forks. The ventral tract has a fainter indication
than in Otis of the outermost branch. It does not appear
again to divide into two.
A striking peculiarity of the bustards is the variability of
the carotids. In Otis and Houbara there are two; in Eupo-
dotis only the right; in Tetrax only the left.
The following are intestinal measurements :-
CUU
-
--
-
-
-
--
--
Small Int.
Large Int.
Caca
-
-
-
--
-
-
-
-
-
-
-------
--------
Inchies
liches
46
28.5
42
-
4.75
11
!
Iuclies
10.5
13.5 and 14
14:5
9.5 and 8.75
7.5 and 9
-
9
Otis tarda
Eupodotis australis
E. kori, . .
E. crabs . . .
| E. Denlami . .
Houbara undulata
H. Macqueeni . .
· Tetrax campestris .
29
4.5
22
4.5
-
18
36
30
31
-
-
6.25
-
-
--
-
-
-
--
-
-
-
--
--- --
LA
The ccecum of Otis tarda is highly remarkable. The
median third of the gut is much dilated, and is lined by a
smooth mucous membrane, which is marked by about seven
slightly raised longitudinal folds, which are visible externally,
but connected with no sacculation. Scattered about are
numerous circular glands, of the size of hemp seed. The
terminal part of each cæcum, which is some two inches in
length, has villi, like intestine. The apical region has not,
but there is a close retiform disposition of mucous membrane,
which gradually passes into longitudinal folds of the middle
OTIDES
333
12
region. The cæca of Eupodotis Denhami appear to be much
the same.
In Eupodotis australis the cæca are not dilated only in
the middle, as are those of Otis tarda, but for the apical
eleven or twelve inches or so. The dilated region is lined
with irregular folds. E. Denhami agrees with 0.tarda. The
liver lobes are equal, or (Tetrax) the right is the larger. A
gall bladder is present.
The bustards (at any rate Eupodotis Denhami) are remark-
able for possessing a rudimentary penis, as does the perhaps
nearly allied Edicnemus. It is a short blunt cone, grooved
above, with a row of glandular pores on each side below.
Internally there are two oval spongy bodies, attached to
anterior part of sphincter muscle, and external to these on
each side are retractor muscles, attached to back of cloaca.
The bustards have a tracheo-bronchial syrinx, but the
intrinsic muscles are either absent or, if present, are but
feebly developed.
Eupodotis australis has perhaps the least modified
syrinx. The first two or three bronchial semi-rings seem
really to belong to the tracheal series, on account of their
greater depth and slighter dividing membranous intervals
than those which follow. The intrinsic muscles are reduced
to a narrow ligament, fanning out somewhat below.
In E. kori the ligament representing the intrinsic muscle
of each side is even feebler, and in E. Denhami it has abso-
lutely vanished.
In all the above species the rings and semi-rings preserve
their independence, and are not fused, except one or two
ventrally to form the pessulus, which is strong and ossi-
fied.
· In Otis, on the other hand, the pessulus is slender and
cartilaginous, being formed by one ring only. There are no
traces of intrinsic muscles.
The genus Houbara has a rather peculiar syrinx, which,
however, like the last, is without intrinsic muscles. It is
compressed from side to side just before the bifurcation.
But the 'waist,' thus formed does not correspond to the
.
CU
1
334
STRUCTURE AND CLASSIFICATION OF BIRDS
1
boundary line between trachea and bronchi; it lies between
the penultimate and antepenultimate tracheal rings.
In front of the last three tracheal rings there is no par-
ticular modification of the trachea. The antepenultimate ring
is strongly ossified in front, where it is convex downwards,
thus leaving a considerable membranous interval between
itself and the ring in front. The next ring is of the same
size, and also ossified in front; the tough and elastic mem-
brane uniting the two can be easily stretched. The last
tracheal ring is much narrower, but also ossified in front; it
passes into the cartilaginous pessulus. Posteriorly these
rings are incomplete, but are joined by a particularly tough
membrane. The bronchial semi-rings are delicate, and not
so long (from before backwards); they naturally diminish
successively in length. The above description refers to H.
Macqueeni, but A. undulata hardly differs.
The bustards exhibit a phenomenon known as 'showing
off,' which is associated with certain anatomical peculiarities.
The appearance of the male bird, when indulging in this
display, is illustrated by a plate which accompanies Dr.
MURIE's paperl upon the subject. The neck is immensely
puffed out, so as actually to trail upon the ground. This
singular behaviour on the part of the cock bird during the
breeding season is not confined to the European Otis tarda;
it has been observed in both Eupodotis australis and E.
Denhami. It is curious that, though the result to all out-
ward appearance is much the same, the mechanism which
produces the inflation of the neck differs in the two cases.
In Eupodotis the anterior section of the oesophagus becomes
dilated. In Otis there is a special pouch developed between
the two halves of the lingual frenum, which extends for a
considerable way down the neck.
The tensores patagii are fairly characteristic. No bustard
. 1 P. 2. S. 1868, p. 471; Sir W. ELLIOT, 'Notes on the Indian Bustard,' &c.,
P.Z. S. 1880, p. 486. See also FLOWER, P. 2. S. 1865, p. 747 ; NEWTON, Ibis,
1862, p. 107; MURIE, P. 2. S. 1869, p. 140; GARRON, ibid. 1874, pp. 471,
673; FORBES, ibid. 1880, p. 477.
· ? Cf. similar pouch in duck Biziura, v. p. 458.
.
335
OTIDES
VII
has a biceps slip. In Eupodotis Denhami the brevis tendon is
a broad fibrous band spreading out after the ulnar muscles
and inserted on to humeral tubercle. In Eupodotis australis
and Houbara Macqueeni there is, in addition, a broad wrist-
ward slip which does not cross the fore arm. In Otis tarda
the extreme degree of complication is reached, for there is,
in addition to the structures described, a slight patagial fan
joining the longus tendon in the usual way.
The anconaus has a tendinous humeral head (at least in
Eripodotis australis and Otis tarda). Otis has no latissi-
mus dorsi posterior.
As in other three-toed birds, the deep flexor tendons are
completely blended.
The gluteus maximus is large and quite covers the
biceps.
The number of cervical vertebre is sixteen, seventeen
(fide GADOW and FÜRBRINGER), or eighteen (Houbara Mac-
queeni). The atlas is notched. In Houbara Macqueeni at
any rate the eleventh to thirteenth cervicals have closely
approximated hæmapophyses. The last hæmapophysis is on
the D1; in the two vertebræ in front these processes are trifid.
Five ribs reach the sternum, all of them with uncinate
processes. The sternum has two notches. There is neither
spina externa nor spina interna.
In the skull the margins of the orbit are very sharp, as in
Edicnemus and Rhinochetus. The interorbital septum is
not greatly fenestrate. The descending process of the lacry-
mal just comes into contact, but does not ankylose, with the
prefrontal process of the ethmoid. The maxillo-palatine
processes are curved and shell-like. In Houbara Macqueeni
at any rate this bóne reaches the jugal arch. The temporal
fossa is guarded by two long and spine-like processes of the
squamosal bones, as in gallinaceous birds, and much more
marked than in Rhinochetus.
The procoracoid is of moderate size and does not reach
the clavicle. The two coracoids are not in contact at their
articulation with sternum. :
I place the bustards in a group by themselves, largely
336
STRUCTURE AND CLASSIFICATION OF BIRDS
2
.2.1
on account of the fact that they are in several respects much
. altered by modification from their allies. They show
evidence of degeneration in the loss of the oil gland, in the
occasional loss of one of the two carotids, in the absence of
the biceps slip, and in the reduced muscle formula of the
leg. GARROD associated with the bustards the Cariamidæ,
Edicnemidæ, Serpentarius, and possibly Phonicopterus.
There is, in my opinion, more to be said in favour of
associating the first two families with the bustards than the
last two. But, as I have pointed out elsewhere, Serpentarius
shows more than one hint of a crane-like origin. As to the
first two groups, they agree with the bustards in the muscle
formula BXY, in the holorhinal nostrils, in the absence of the
biceps slip (Cariama), the absence of basipterygoid processes,
the absence or feeble development of intrinsic muscles to the
syrinx; the oil gland too, absent in the bustards, is nude in the
cariamas, and thus shows a commencing reduction. But these
various cases of reduction cannot be held to be necessarily
indications of relationship. I should, however, lay some stress
upon the holorhinal nostrils, the leg muscles, and the syrinx;
in this case the same conclusion as that advanced by
FÜRBRINGER is arrived at, viz. that the Otides come nearest
to the Edicnemidæ. The very difficulty of associating the
Otides with either gruiform or charadriiform birds is evidence
of the common descent of all three divisions of the class.
LIMICOLÆ
Definition.---Oil gland feathered. Aftershaft present. Aquincubital.
Skull schizognathous. Both carotids present. Cæca nearly
always large. Ambiensalways present. Biceps slip to patagium
nearly always present.
This is a large group of birds which are cosmopolitan in
range and embrace a variety of types, which may perhaps
be arranged in six families. The type family is that of the
SEEBOHM, The Geographical Distribution of the Charadriidæ, &c., London,
1887. A monograph of all the species (excl. gulls).
? Rhynchups is alone exceptional in having no ambiens.
LIMICOLÆ
337
TY
Charadriidæ, which contains the largest number of genera ;
the remaining families are not separated from it by very
numerous points of difference, and the group as a whole is
very near to the gulls, which I only divide as a family. The
birds of this group, though they are generally good flyers, are
mostly found upon the margins of the sea or of marshes and
pools; and their long bills are apparently constructed with a
view to probing the mud and sand of such localities for their
food, which is, with the exception of the vegetable-feeding
Thinocoridæ, animal. The bill is usually long, and, in the
woodcock, soft at the extremity, reminding us of the bill of
Apteryx, being used, indeed, for the same purpose, to extract
earthworms. In the curlew (Numenius) the bill is curved
downwards, as in the ibis. In the avocet (Recurvirostra
avocetta) it is curved upwards; in Eurynorhynchus it is
spatulate at the extremity, and, finally, in the crooked-billed
plover it is bent sideways. The legs are often long, and the
toes moderately or very much so (Parridæ). There are either
four toes, the hallux being small, as in the whimbrels,
pratincole, &c., or the hallux and the remaining toes also are
of enormous length, as in the Parridæ only; in many forms,
such as the stilt plover, the hallux is absent. In Recurvi-
rostra and Himantopus andinus the feet are well webbed.
In the phalaropes the feet are lobate. The colour of these
last-mentioned birds is suggestive of that of the mature gulls,
just as the markings of the immature gulls is suggestive of
the coloration of many Limicolæ, such as the dunlin, knot, &c.
The number of rectrices varies from ten in Rhynchoa and
twelve in Eurynorhynchus to as many as twenty-six in
Scolopax. The face in Lobivanellus is adorned with fleshy
lobes, so often found in birds.
The pterylosis of the Limicolæ has been chiefly studied
by NITZSCH,' who figures Scolopax and Charadrius. The dor-
sal tract, single on the neck, bifurcates between the shoulders
into two strong bands, which either are (Scolopax) or are not
(Charadrius) continuous with the anteriorly bifurcate pos-
terior section of the dorsal tract. The ventral tract divides
i See also ANDERSON as quoted on p. 343.
1
nn
UUUU
LCU
338
STRUCTURE AND CLASSIFICATION OF BIRDS
I'M
A
NR
at the beginning of the neck; on the breast each half gives off
a strong lateral branch.
All the Charadriidæ, and indeed all the Limicolæ,' are schi-
zognathous; but many of them have not the typical condition
of the vomer which accompanies as a rule the schizognathous
skull. In the woodcut (fig. 169) a few exceptions to this are
given, which range from the typical
condition observable in Sterna to an
excavated extremity, such as charac-
terises Recurvirostra. In Chionis the
vomer ends in the typical manner, i.e.
in a point; but it is exceedingly broad
before its termination, and therefore
quite unusual.
In Thinocorus and Attagis the
vomer is short and broad, and almost
passerine in form.
The maxillo-palatines are, as a
rule, thin and scroll-like plates, which
are bent downwards and often defi-
cient in ossification, leaving holes here
and there. The palatines have a
spout-like process, extending upwards
towards the base of the skull, which
is especially well marked in Edicne-
mus. The Limicolæ are nearly all of
them schizorhinal, the delicate bar of
Fig. 168. - UNDER VIEW or
SKULL or Charadrius pluvi- the premaxilla being inserted at a
alis (AFTER HUXLEY).
different plane from the attachment
Pmz, premaxilla ; Vo. vomer; Mx,
maxilla; Pi, palatine; R, ros of the nasals to the frontals. In the
palatines ; *, ectetlimoid. Charadriidæ proper there are a pair of
largish occipital vacuities, one on either side of the foramen
magnum. These same birds have basi-occipital processes,

LAG
.
2
Aft
..!
RAH
wand
.
.
7
17
7:1722
Alap
A
17
.
KNIHY
le
"
11
VUE
ICM
FOTO
2
21.
11
PAVILI
Het
WL
1
11
uw
.
llo
26
RAPOVI
*
Mr.
11
maxilla; PP, palatine; R, ros-
trum; Na, nasa! ; Mliep, waxillo-
SHUFELDT (* Contributions to the Comparative Osteology of Arctic and
Subarctic Water Birds,' J. Anat. Phys. 1989 and 1890) figures a few skulls of
Limicolæ. See also the same, 'On Aphriza virgata,' Juurn. Morph. ii. p. 311.
See also Osteology of Numerius,' &c., Journ. Anat. Phys. 1885, p. 51;
• Observations on the Osteology of Podlasocys inontarus,' ibid. 1884, p. 86.
LIMICOLÆ
339
which vary somewhat in the degree of their development. The
lacrymal bone articulates with the ectethmoid, and makes a
complete arch of bone in the anterior region of the orbit. The
bones are particularly slender in Himantopus, leaving, there-
fore, a large vacuity. In one or two types the foramen of the
arch is almost obliterated by the thickness of the ectethmoid.
The upper margin of the orbits in the Charadriidæ is marked
with conspicuous grooves for the supra-orbital glands.
There are fifteen cervical vertebræ in Hematopus, Ni-
menius, &c.
The atlas is perforated by the odontoid (Numenius,
2002
UU
FIG. 169.--VOMERS OF VARIOUS Limicolce (AFTER GARROD).
1. Sterna Tvirundo. 2. Hematopus Ostralegus.
3. Numenius arquatus. 4. Recurvirostra avocetta.
5. Chionis alba.
ra
Limosa). The Limicolæ differ from the Grues in the fact that
only one or two vertebræ (the ninth in Limosa) are furnished
with two fairly closely approximated hæmapophyses for the
reception of the carotids. In. Numenius these exist on the
ninth and tenth, and there are traces on the eleventh. The
first dorsal vertebra, or the first two, has a large distally
expanded hæmapophysis, an indication of a state of affairs
which is carried much further in the allied group of Alcæ (q.v.)
In these points the gulls may be contrasted with the more
typical Limicolæ. There are no paired hæmapophyses borne
by the centra.
The unpaired hæmapophyses extend (in Lestris) from C10
to C15; on D1-3 there are slightly bifid hæmapophyses. The
atlas is notched.
In Chionis C10 has a slightly excavated hæmapophysis,
2 2
340
OF BIRDS
7
STRUCTURE AND CLASSIFICATION a trace of the double one of other birds. The hæmapophyses
of D1, D2 are the longest, and the former is slightly trifid;
this trifidity is very marked in the case of the two last cervicals.
The atlas is notched.
In Parra, as in the typical Limicolæ, the atlas is perforated
by the odontoid process. On the eleventh vertebra only do
the two processes, which form an incompletely closed canal
for the carotids, approach each other markedly in the middle
line. The first dorsal vertebra has the largest hæmapophysis,
which is flattened slightly distally.
(Ediciemus, with a notched atlas, has paired ventral out-
growths for the carotid, closely approximated only on C10.
The three following have median blade-like hæmapophyses.
On the fourteenth to sixteenth there are lateral outgrowths
of these. The first dorsal has the last and the strongest
hæmapophysis.
In Attagis the atlas is perforated ; the hæmapophyses
are very feeble.
In Limosa and in other genera the clavicle is attached
by ligaments to the acrocoracoid, procoracoid (which is mode-
rately developed and curved upwards), and scapula. The two
coracoids are not in contact at articulation with sternum ;
the latter is two-notched and has the spina externa only; six
ribs reach it. The same statements may be made about
Hæmatopus and Numenius, Eudromias (all examined by
myself), as well as other genera.
The pelvis of Numerius may serve as a type for that of
the Limicolæ.
The preacetabular portion of the ilium is about equal
in length to the postacetabular portion of that bone; the
tivo bones are excavated horizontally, and are just prevented
from coming into contact by the fused neural spines of the
1 rtebræ. The pubes are strongish bones and not fused with
te ischia. The ischia end in long thin processes which
· tend back beyond the ilia and nearly as far as the ends of
ne pubes. Hæmatopus and Limosa are much the same.
hionis hardly differs. In Parra the pelvis has rather more
e look of that of a rail. The pelvis of Attagis is wider
12001
VUUUU
1
LIMICOLÆ
341
22)
III
1722222.21
DITULO
O
than that of other Limicolæ, and the ilia are rather further
apart. In (Edicnemus bistriatus, but not in E. grallarius,
the ischium has a well-marked pubic process, which reaches
the pubis.
As to the muscular anatomy, there is great uniformity in
the tensores patagii of this group. Charadrius pluvialis
may serve as a type. In that bird there is a biceps slip ; the
tensor brevis early divides into two, of which the anterior is
again divided not far from its ending; a recurrent slip runs
to the longus.
The same disposition of tendons is found in Glareola,
Numenius, Scolopax, Himantopus, Vanellus, Machetes, Parra,
Recurvirostra, Totanus, Limosa, the only differences being
that in some (e.g. Parra jacana) the middle only of the three
tendons which are inserted upon the fore arm is continued
over the muscles of the fore arm to the lower border of the
ulna, while in others (e.g. Numenius) both the principal
tendons are thus continued. In Glareola the middle and
wristward tendons are thus continued.
Vanellus cristatus has been recorded with two separate
biceps slips, which both run to the tendon of the longus. In
Tringa cqnutus I found a second biceps slip, largely but not
entirely tendinous, which is attached to the outer of the two
main tendons of the tensor brevis, this latter tendon indeed
only dividing into two near its insertion on to the ulna.
In Gallinago the recurrent slip connecting the two
tensores seems to be absent.
In Gambetta flavipes GARROD found no biceps slip at
all, and it seems also to be absent in Metopidius afri-
Carus.
Thinocorus rumicivorus has the typical pluvialine arrange-
ment of the tensores tendons that has been already described,
but the biceps slip is remarkable for the fact that it has a
tendinous band running along it. The characters of the
tensores patagii in this group are fairly distinctive and at
any rate serve to distinguish the Limicolæ from the Ralli.
They do not, however, permit of the enforcement of any
| FORBES, P. 2. S. 1881, p.
VU
342
STRUCTURE AND CLASSIFICATION OF BIRDS
UU
views respecting the families into which the Limicolæ have
been divided.
An expansor secundariorum is almost universally present,
but is often feebly developed. It appears to be absent in
Tringa canutus and Chionis.
The biceps is so far noteworthy that only the coracoidal
head is present in Rhynchæa and in Parrci sinensis. The
condition of this muscle in Himantopus is extremely
interesting. It is stated by Dr. GADOW (on the authority of
MECKEL) to be a double muscle. In H. nigricollis I find
the following arrangement : There are two distinct portions-
(1) a part which may perhaps correspond to the entire biceps.
of other birds, with two heads, a coracoidal and a humeral;
from the former of these arises the biceps slip : (2) in addi-
tion there is a distinct coracoidal portion, with a fleshy
belly, which has, however, a common origin from the coracoid
with the coracoidal head of the main muscle. Something of
the same kind appears to occur in Chionis and Scolopax ; it
may obviously be compared with the gulls (9.v.) In Cur"-
sorius the biceps was also double, though the division only
commenced a little below the level of the humeral attachment.
In Lobivanellus there were indications merely of the same
division in the lower part of the belly of the muscle. Glareolcu
has a biceps which is double for the greater part of its course.
The anconaus appears to invariably possess the tendinous
humeral head.
My remaining notes upon the myology of the group are
scanty. In Lobivanellus atronuchalis, the seinimembranosus
and semitendinosus are inserted by a common tendon, and
the latter gives off a branch to gastrocnemius. There is but
one peroneal muscle (the longus). The latter is alone
present in Chionis alba and Himantopus nigricollis. The
pectoralis primus in these birds does not appear to be
divided into two layers.
There is some variation in the deep flexor tendons of this
group.
In this bird the biceps slip arises (as figured by FÜRBRINGER) from the
humerus itself.
117
CU U
LIMICOLÆ
343
In Totanus calidris there is a slender vinculum, and, in
addition, the flexor hallucis gives off a special slip to the
branch of the flexor communis which supplies the second
digit. The arrangement, in fact, is like that in Scopus, in
many Accipitres, &c. In the Parridæ, on the other hand, the
tendons blend early upon the ankle, and in those that have
been examined no branch to the hallux has been discovered.
Chionis alba has the deep flexor tendons of Totanus.
In all Charadriidæ the ambiens is present. The genera
Charadrius, Calidris, Gambetta, Gallinago, Limosa, Ma-
chetes, Scolopax, Strepsilas, Totanus, Tringa, and Vanellus
have the reduced formula AXY+.
In Hæmatopus, Himantopus, Recurvirostra, Ægialitis,
Numenius, there is the full formula ABXY+; so, too, in the
representatives of the remaining families of the Charadrii,
with the sole exception of the Australian thickknee, Bur-
rhinus, and some Edicnemus, which have the formula BXY+.
With the exception of the Parridæ (q.v.) the charadrii-
form birds have well-developed cæca. The intestinal mea-
surements of a few types are as follows:
Small Int.
:
Large Int.
Cæca
-
.--.
-
34
21 (3)
و مرا با نه
or J. o
O c
QQQQIRA
-
13
18
--
10W
Inchies
Inchies
Inches
Hematopus ostrulegus
1:6
2.75
Edicnemus crepitans
22 (32)
2} (3)
u grallarius
16 (17)
, superciliaris .
, bistrictus
Himantopus brasiliensis .
Numenius arquatus .
Strepsilas interpres.
Gambetta flavipes .
Glareola pratincola .
Scolopax rusticola .
Gallinago gallinula .
Tringa canutus .
Liinosa rufa . .
Numenius phaeopus.
20
Vanellus cayennensis
18
Recurvirostru avocettil
41 (30)
Hydrophasicinus chirurga.
12
Thinocorus rumicivorus .
12.6
21 and 21
Chionis alba, . . .
1.75 8.25 and 9
Attagis . . .
Ai
llocsolá
-
-
--
-
---
123
33
12.5
Eurynorhynchus Pygmeus ?
8.75
•88 I •7
-
1 The brackets coutaing measurements of a second specimen.
" ANDERSON, 'On the Pterylosis, &c., of the Spoou-billed Sandpiper,' 77. Linn. Soc. (2), i. p. 213.
DIC972
CIUL
.--
.-
344
1
STRUCTURE AND CLASSIFICATION OF BIRDS
Comments upon the facts set forth in the above table must
obviously be discounted by the variations (quite considerable
in amount) which occur in one or two of the species. The
table given by GADOW 1 increases the number and extent of
the individual differences in intestinal length.
In the liver the right lobe is, as a rule, larger than the
left. Sometimes it is only slightly so; but in Charadrius
pluvialis the right lobe is twice as large. In Scolopax ruusti-
cola and in Edicnemus crepitans the lobes are equal. The
gall bladder is nearly always present. GADOW did not find it
in a specimen of Numenius arquatus and of Tringa arenaria
and T. alpina. This, however, appears to be individual.
In all the Charadriidæ the syrinx is of the tracheo-bron-
chial pattern.
In Vanellus cayennensis 2 (fig. 45, p. 66) the last twenty-
five tracheal rings are narrower than those which precede them,
and of equal diameter throughout. The first two bronchial
semi-rings are like split tracheal rings; the next two are very
closely applied together ; the remainder are normal bronchial
semi-rings with no modification. The most remarkable fact
about the windpipe is the enormous size of the intrinsic
muscles, of which, however, there is only a single pair. The
muscles end in a tendon, which is inserted on to the second,
third, and fourth semi-rings. In l'anellus cristatus the intrin-
sic muscles are certainly large, but not so abnormal as in the
other species of the genus. Only the last four tracheal rings
are modified, and in front they are all fused in the middle
line to form a bony box; behind the last three tracheal rings
are semi-rings, the pessulus being attached to the fourth.
The muscles are attached to the first bronchial semi-ring.
In Himantopus nigricollis there was no trace what-
ever, that I could detect, of these muscles ; nor in H.
brasiliensis. Charadrius pluvialis, Hematopus ostra-
legus, and Squatarola helvetica are also without these
muscles. On the other hand they are present in Totanus
UVC
In Bronn's Thicrreich, “Aves,' p. 624.
2 GARROD, 'On the Trachea of Tantalus loculator and of Vanellus cayen-
izcilsis,'P. Z. S. 1878, p. 625.
LIMICOLAE
345
canutus, Tringa cinclus, Numenius arquatus, Ægialitis
hiaticula, Limosa rufa, L. @gocephala, Machetes pugnax,
Strepsilas interpres, and Scolopax rusticola. But although
the muscles are present in the birds included in the second
list they do not, in all of them at least, reach as far as the
bronchi, though they may possibly be continued by fibrous
tissue to a more normal point of attachment. Thus in
Limosa cegocephala the muscles stop three or four rings
before the end of the trachea. In Scolopax rusticola, on the
other hand, the rather broad intrinsic muscles reach as far as
the first bronchial semi-ring.
The windpipe of the Indian painted snipe (Rhynchæa
capensis) is peculiar in that it is convoluted slightly in the
female, not in the male, as might be expected in view of this
frequent difference between the sexes in other birds. As has
been pointed out, the female is the larger and more richly
coloured of the two, a fact which is in harmony with the
more complicated trachea.
This is not seen in young females. The same condition
is stated by GOULD to characterise the Australian R. aus-
tralis.
The large group of the Limicolæ has been variously
divided. I follow GADOW in the families, but include also the
Laridæ, which I separate from the auks. I should define
the Charadriidæ, to which most of the foregoing refers, as
schizorhinal birds, with occipital fontanelles, furrows for
supra-orbital glands and basipterygoid processes, and fifteen
cervical vertebræ.
TT
1
The family Edicnemidæ has been instituted for the genus
Edicnemus, which includes the Norfolk plover and a number
of other species closely allied; these range widely, being only
absent from North America, Central Asia, and New Zealand.
The Australian E.grallarius has been separated as a distinct
genus, Burhinus, which, as also E. crepitans, instead of
possessing the complete muscle formula (ABXY+), as in
LUCI
i Wood-Mason, 'On the Structure and Development of the Trachea in the
Indian Painted Snipe (Rhynchæa capensis),' P. Z. S. 1878, p. 745.
346
STRUCTURE AND CLASSIFICATION OF BIRDS
the other members of the genus, has the formula BXY+.
The pterylosis is as in the Charadriidæ, but the number of
rectrices may be as numerous as fourteen. There is no
hallux. In the skull the absence of basipterygoid processes
(sometimes indications of them are present, according to
GADOW) and the holorhinal character of the nostrils distin-
guish this family from the Charadriidæ. The depressions
for the supra-orbital glands are well marked. The lacrymal
bones are nearly (occasionally quite, though by suture)
united with a process of the frontals, and form a canal,
through which the gland apparently passes ; this is seen in a
more exaggerated way in Chionis and in Vanellus (v. de-
scription of Chionididæ). The post-orbital angle is not
distinct from the post-frontal process. There are no occipi-
tal foramina, as in Charadriidæ. There are sixteen cervical
vertebre, the last three of which have ribs of progressively
increasing length; five or six ribs articulate with sternum.
Contrary to what is found in the Charadriidæ, the coracoids
slightly overlap at their external articulation.
Some of the visceral characters have been already dealt
with above in the general description of the Limicolæ.
There is a tendency for the ambiens not to cross the knee ;
this occurs individually with specimens of several species.
The syrint has not, except as an occasional variation,
any intrinsic muscles.
Edicnenus bistriatus has on the anterior wall of the
cloaca two hardly elevated ridges, which end by slightly free
points, and seem to represent a rudimentary penis.
The surgeon birds and jaçanas of the tropical regions of
the Old and New Worlds, with their enormously elongated
feet and their somewhat rail-like aspect, are now known to
belong to the Limicolæ (and not to the Ralli), of which they
may be regarded as forming a distinct family, Parridæ.
Their anatomy has been chiefly studied by FORBES. As
with the Thinocoridæ so with the present family there is a
character of the alimentary canal which immediately distin-
1Notes on the Anatomy of the Jaçanas,' P. 2. S. 1881, p. 639.
2
LIMICOLE
347
guishes them from all their allies. In this family the cæca
are mere passeriform nipples, measuring from 15 to 2 of an
inch in length.
The muscular anatomy has already been to some extent
treated of in connection with the structure of the entire group
of birds of which the present genera form a family. In all
of them, Parra, Hydrophasianus, and Metopidius, the mus-
cle formula is complete, i.e. ABXY+. The condition of the
deep flexor tendons of the foot is very singular. As FORBES
justly pointed out, the peculiarly large size of the hallux (as
of all the digits) of the foot in these birds seems to be un-
reconcilable with the entire absence of a special slip from the
conjoined tendon of the long flexors. This fact,' he thinks,
seems to indicate that the Parridæ may have been developed
from some form with a more normal-sized foot, and a small
hallux which had no special long flexor, the great size of
their feet having been developed in accordance with their
peculiar habits.
The syrinx has a pair of intrinsic muscles.
The skull has well-formed basipterygoid processes, but
no occipital foramina or supra-orbital impressions. In
Metopidius the radius is extraordinarily enlarged (see fig. 70,
p. 125). In the remaining genera there is no such modifica-
tion of the bone, but there is a metacarpal spur, which may
be of the same use, i.e. for fighting. In Parra the clavicle
is at its articulation further from the procoracoid than in the
Charadriidæ, and the sternum has only one pair of notches.
Five ribs reach it.
The single genus Chionis, of antarctic range and some-
what gull-like form, makes up the family Chionididæ.
There are twelve rectrices.
The skull is peculiar in that the grooves for the supra-
orbital glands end in a large foramen on each side, which is
The bones of Parra albinucha are described and figured by MILNE-EDWARDS,
Hist. Madagascar.
? The peculiar sheath which covers the base of the bill and the nostrils
(whence 'Sheathbill') is declared by STUDER to be developmentally different
from the tube of the Tubinares.
348
STRUCTURE AND CLASSIFICATION OF BIRDS
9.
U
7
11
formed by the union of the lacrymal with a process of the
frontal, forming a continuous bony bar. As has been already
mentioned, Edicnemus shows a very considerable approach to
this state of affairs. So too, as I interpret it, do the quite
typical charadriid Vanellus and Eudromas. In these birds
the grooves for the supra-orbital glands do not, as they
do in Limosa and Recurvirostra, border the margin of the
orbit. They are situated at some distance from it, and each
ends in a very small foramen, bordered in front by the
ankylosed lacrymal, which I take to correspond to the large
foramen of Chionis.
There are no occipital foramina or basipterygoid pro-
cesses.
The cervical vertebræ are fifteen, of which the last three
bear discrete ribs; six ribs reach the two-notched sternum,
and there is one behind. The clavicles have no hypocleidium,
and end a long way in front of carina. The coracoids are
not in contact at sternal articulation.
The muscle formula is ABXY+.
The syrinx of Chionis is not widely different from that
of other Limicolæ, and exhibits, as will be seen from the fol-
lowing description, no particular resemblance to the Galli. As
is the case in so many Limicolæ, the intrinsic muscles end as
such some way in front of the bifurcation of the windpipe,
though they are continued on to the bronchi by fibrous tissue.
They end in Chionis upon the fifth tracheal ring counting
from the last.
The last four tracheal rings are more or less closely united
to form an ossified box. The first bronchial semi-ring to
which the fibrous continuation of the intrinsic muscles is
attached is the widest (from before backwards) of the rings
of the windpipe, and is deeper than the bronchial semi-rings
which follow.'
i The following are the principal memoirs dealing with the anatomy of this
bird : EYTON, • Note on the Skeleton of the Sheathbill,' P. 2. S. 1858, p. 99 ;
A. REICHENOW, Osteologie von Chionis minor,' &c., J. f. 0. xxiv. 1876, p. 84;
SHUFELDT, The Chionidæ : & Review of the Opinions on the Systematic
Position of the Family,' Auk, 1893, p. 158, and in ' Contributions to Comparative
Osteology,' &c., J. Anat. Phys. 1891, p. 509 ; KIDDER and COUES, ‘A Study of
LIMICOLA
349
17
V
It is usual to separate the two genera Thinocorus and
Attagis, both South American birds, into a family, Thinoco-
ridæ. In contradistinction to their allies they are grain-
eating birds, connected with which habit is the presence of a
crop, an absolutely distinctive character so far as the present
group is concerned. Their anatomy has been chiefly studied
by GARROD.' The differences which distinguish them from


.
SN
S
AG
.
.
.
21
SIS
-
-
ET
21B
-
Z:..
-
*1.
da
10.
VV
.
a
SUNT
-
.
2
-
22
.
4.
-
.
-
-
INT
-
.
+
.
WTB
.
HULL
*
IT WE
Orie
US
2
SE
ent
WO
L2
.
WA12
,3
TISSA
Wh
.
BA
7.3
ASTERS
TA
.
.
6
UN
JUIN
WWIIU
"
i
.
HH
22/
•
1
.
A
A
(
DURA
277
M
%
WA
M
UNISI.
NA
.
!
la
1.
*
*
DS
HL.
1
.
.
.
2212
V
.
/
WPi 14
Will112
M
.
in
91
22
TV.
Sit
.
..NU
RUK
PLA
MAY
1.
.
.!
..
IRITVI
USE
UNI
Fig. 170.-SKULL or Attagis Gayi (AFTER GARROD).
other Limicolæ are neither great nor numerous. In the skull
the basipterygoid processes are absent, and the vomer is broad
and rounded in front as figured by PARKER ; ? the skull, in fact,
as has been mentioned on a previous page, is ægithognathous
rather than schizognathous. There are no occipital foramina,
y
Chionis minor',' Bull. U.S. Nat. Mus. iii. 1876, p. 85; R. O. CUNNINGHAM, · On
Chionis alba,' J. Anat. Phys. 1870, p. 87 ; BLAINVILLE, "Mémcire sur la Place
que doit occuper le Genre Chionis,' Ann. Sci. Nat. 1836, p. 97 ; STUDER,
Forschungsreise S. M. S.' Gazelle,' Bd. iii. - Zoologie u. Geologie,' p. 107.
I'Notes on the Anatomy and Systematic Position of the Genera Thinocorus
and Attagis,' P.Z. S. 1877, p. 413.
2.On Ægithognathous Birds,' Zool. Trans. vol. x.
350
STRUCTURE AND CLASSIFICATION OF BIRDS
but the supra-orbital impressions are present. The maxillo-
palatines are very far apart, and besides being short are
swollen instead of being leaflike plates. The same pseudo-
holorhiny that characterises the Glareolidæ is also found in the
present family. Five ribs reach the sternum. The coracoids
are quite separate at their insertion on to sternum. The
muscular formula of the two genera is the complete one
ABXY+.
In Thinocorus rumicivorus the syrinx has a pair of
lateral muscles, which are attached to the fourth incomplete
ring when seen from in front. This is probably the first
bronchial, the last three tracheal rings being thus incomplete.
.
Glareola, Cursorius, Pluvianus, and Dromas, all Old-World
genera, are included in a separate family, Glareolidæ, which
GARROD regarded as very near akin to the Thinocoridæ. As
in them, basipterygoid processes and occipital fontanelles are
absent, and impressions of supra-orbital glands present. The
muscle formula too is complete, and the syrinx has intrinsic
muscles.
Except in Cursorius there is a hallux. FORBES, with
some reason, has united into a group Pluviales, equivalent to
the rest of the Limicolæ, this family, together with the Thino-
corida and Chionididæ, mainly on account of the above
combination of skull characters found in no other Limicolæ.
As in them also there is pseudo-holorhiny, the bony
nostrils, though extending back beyond the nasal process of
the premaxilla, being distinctly rounded off.
Pluvianus, however, has typically holorhinal nostrils.
In Cursorius the grooves for nasal glands are converted
into elongated foramina by a fusion between adjacent pro-
cesses of the skull.
The gulls form another distinct family, Laridæ, containing
the genera Larus, Lestris, Sterna, Rhynchops, Anous, and
Gygis.
The skull is schizorhinal and schizognathous, without
1 LINNAUS placed Glarcola in genus Hirundo, SUNDEVALL in Caprimulgidæ.
LIMICOLÆ
351
I
basipterygoid processes or occipital fontanelles, but with
well-marked grooves for supra-orbital glands. In Lestris
antarcticus at any rate there is a foramen formed round
anterior end of supra-orbital groove, as in Chionis (q.v.) In
Lestris there is a distinct tendency towards the pseudo-holo-
rhinal condition of the Thinocorida and Glareolidæ.
In Larus the relations of the clavicles, scapula, and cora-
coids are as in the Charadriidæ; but the clavicles provided with
a hypocleidium come into nearer relations with the carina
sterni, to which they are attached by a ligament. The cora-
coids are in contact behind the spina (externa) sterni. The
same statement may be made of Lestris.
The cervical vertebræ are fifteen in number. The dorsal
vertebræ are, as in Alcidæ and plovers, opisthocoelous. Six
(Lestris antarcticus) or seven ribs articulate with the sternum. .
The first phalanx of the second is commonly perforated.2
As to the pterylosis, the plan is that of the Limicolæ, but
the ventral tract does not divide until some way down the
neck. The feet are webbed, the hallux is small or absent,
and there are twelve rectrices.
The muscular formula of Rissa tridactyla is AX+; of
Larus, Stercorarius, and Gygis, AXY+. The other genera
have the complete formula ABXY+. Rhynchops has no
ambiens.
In Lestris crepidatus and L. antarcticus the semi-
membranosus is sometimes two-headed, one arising from
ischium and one from postacetabular ridge of ilium.
The tensores patagii 3 (see fig. 171) are on the plan of
10
| These are present in the young: see PARKER, Linn. Trans. (2), i. p. 142.
? This does not, however, as it has been stated to do, distinguish the Laridæ
from other Limicolae ; though apparently universal in the gulls (including
Arous and Gygis), the same perforations are found in Glarcola. The value of
this anatomical fact may be judged by the perforation of the same bone in such
varied types as Pterocles, Coracopsis obscura, (not in C. nigra), Psittacula
passerina, Macharhaipirus Andersoni, Heliodilus, Caprimulgus, Phaethon
candidus (not P. rubricauda), and Fregata ninor. These instances are taken
from the osteological plates illustrating MM. GRANDIDIER and MILNE-EDWARDS'S
Histoire Naturelle de Madagascar.
? For muscular anatomy of Laridæ see GIEBEL, “ Beiträge zur Anatomie
d. Möven,' &c., Zeitschr. f. d. ges. Naturw. X. (1857), p. 20; BEDDARD, 'A
Contribution to the Knowledge of the Anatomy of Rhynchops,' P. 2. S. 1896,
p. 299.
352
STRUCTURE AND CLASSIFICATION OF BIRDS
L
1
those of other limicoline birds, but are apt to be a little more
complicated. In Larus argentatus, of which the tendons are
represented in the annexed cut, the anterior stronger branch
of the brevis tendon gives off a forwards and downwards slip
to the extensors of the fore arm, from which arises the usual
connection with the longus tendon. There is a second con-
nection between the two tendons. At the origin of the

ww
P2P
..
.
.
.
i
1
---6.pl
111
INDIA
VI
TO
VIZ
.
ATNUVILIN
.
W
IV
W
or
MOTII
K
mil
10
UWIN
R
.
VINI
INIUM
RUTIITTITTIINTIMITUITINIUM
Fig. 171.-TENSORES PATAGII Or Rhynchops (AFTER BEDDARI)).
1.p.?, tensor longus; 1.p.!, tensor brevis; B, wristward slip; I", patagial fan';
A, tendons to ulnar side of arm.
patagial fan is a bony nodule, as in the petrel. The tensor
longus tendon also gives off a slip (A, fig. 172) to the inside
of fore arm which is also present in the auks (q.v.) In
Rhynchops (fig. 171, A) there are two such tendons.
Lestris antarctica, Sterna, and Larus marinus (according
to FÜRBRINGER's figure, Pl. xix.) are much the same, but are
without the additional slips A and B. Of these A is present
in Rissa tridactyla.
The expansor secundariorum is frequently absent, but it
LIMICOLÆ
353
is present in Larus argentatus, marinus, and glaucus, not
in fuscus. It is absent in Sterna and Lestris ; present in
Anous; absent again in Rhynchops.
The biceps is peculiar in some members of this family.
In Larus, Sterna, and Anous the biceps has, as usual, the
two heads, humeral and coracoidal; but they form two per-
fectly distinct muscles, of which one, the coracoidal, soon
divides into two distinct muscles again, which are inserted

..
A-t.22.7.
67274
OT
All
SON
I
1
.
.
.
.
.
.
.
.
.
.
.....
...
.........
FIG. 172.--TENSORES PATAGII OF Larus argentatus (AFTER BEDDARD
FROM FORBES).
12, osseous nodule. Other letters as in fig. 171.
respectively upon the radius and ulna. The biceps head
goes to the radius, and as a rule gives off the biceps slip to
the patagium; but in Larus ridibundus, according to FÜR-
BRINGER, this slip arises from the coracoids, an anomaly
observable also in the petrel, Thalassiarche. Rhynchops
has no biceps slip at all.
The anconaus is generally attached by a tendon to the
humerus.
A A
35+
STRUCTURE AND CLASSIFICATION OF BIRDS
1
The cæca vary considerably in their development, as the
following table of measurements shows:-
Small Int.
Сеса
Large Iut.
S-
.-
V
•5 (25)
3.25 (1)
2.75
.
-
Larus argentatus.
1 glaucus .
, ridibundus.
u · Jamesoni .
Lestris pomatorhinus
, antarcticus
, crepidatus.
Sternza cantiaca .
Rissa tridactyla .
56.25 (36)
66
26
12.9
30.5
• 25
.12
3
3.4
2.25
1.75
3.5
38
18.5
24
Gy V I
-25
25
The lobes of the liver are subequal in Sterna, Anous,
Gygis, and Rissa. In Larus and Lestris the right is the
larger. A gall bladder is always present.
In Anous the cæca are quite short; in Gygis long and
charadriine.
The syrinx of this family is typically tracheo-bronchial
(at any rate in Larus), with well-developed muscles, which
always reach the bronchi. The family thus differs from
other Limicolæ where there is a tendency towards a retro-
gression of the intrinsic muscles, sometimes culminating in
actual disappearance.
In Larus marinus the last six or seven tracheal rings
are rather narrower from above downwards than those
which precede them, and are more or less firmly attached
(except the last ring, which is incomplete both in front and
behind) to form a box. When the syrinx is viewed from
behind, a broad three-way piece is seen, into the formation of
which the penultimate tracheal ring and the four or five in
front of it appear to enter. This piece, however, is only
really solid at the edges, the bars being a continuation of
the penultimate tracheal rings. In the middle it is so thin
as to be little more than a membrane. The first bronchial
semi-ring (to which the intrinsic muscles are attached) is
bow-shaped and in close contact with the last tracheal ring.
The remaining semi-rings are narrower and run in a straight
direction across the bronchi.
The membrana tympaniformis is distinguished by its
.
:
LIMICOLÆ
355
UT
thinness and transparency from the thick yellowish mem-
brane which unites the edges of the greater number of the
bronchial semi-rings.
In Larus fuscus and L. glaucus the differences are but
slight, and chiefly concern the greater solidity of the three-
way piece.
In Larus argentatus the edges of the three-way piece
are most solid; but they are connected by a series of four
or five bars which divide up the central region of the three-
way. piece into alternate thicker and thinner portions. This
is a peculiar specialisation of the three-way piece which I
have not observed elsewhere. There is, furthermore, a thin
bony curved rod, closely applied to the outside of the three-
way piece, which arises from, or is at least connected with, the
last tracheal ring.
Lestris antarcticiis has a syrinx which is rather different
from that of Larus, and which points in the direction of the
Charadriidæ, owing to the fact that the intrinsic muscles do
not reach the bronchial semi-ring except as a fibrous band.
The three-way piece, which is solid, is formed by two or three
tracheal rings ; there is no differentiation in membrane
closing bronchial semi-rings.
It is evident from the foregoing account that, while there
are a few differences between the various genera of Laridæ,
Rhynchops is quite the most anomalous form in structure as
well as in external appearance, as seen in its remarkable bill,
with its scissor-like edge and projecting mandible. Still,
the differences are, in my opinion, not sufficient to place
Rhynchops in a family by itself opposite to the remaining
Laridæ. It seeins that the usually received division of the
family, making an additional one for Rhynchops, will serve to ·
divide naturally the Laridæ ; we may term these divisions
subfamilies. They will be thus characterised :-
12
IT
ON
UILL
1Cu.
Subfamily I. Larinæ.
Muscle formula of the leg, AXY+. Cæca ludi-
mentary. Biceps slips and expansor SCCUN-
dariorum present.
356
STRUCTURE AND CLASSIFICATION OF BIRDS
, Subfamily II. Stercorariinæ. . .
Muscular formula, AXY+. Cæca long. Biceps
slip present. Expansor secundariorum absent.
Subfamily III. Sterninæ.
Muscular fornula, ABXY+. Cæca rudimentary.
Biceps slip present. Expansor secundariorum
absent.
Subfamily IV. Rhynchopinæ.
Muscular formula, ABXY-. Cæca rudimentary.
Biceps slip and expansor secundariorum absent.
Gygis and Anous require further investigation before they
can be placed in this system; they are usually regarded as
terns-by HOWARD SAUNDERS, for example. Anous has the
complete muscle formula. Gygis has the formula of the
gulls; but then the tern, Sternula (sp.), wants the accessory
femoro-caudal, and in this approaches the gulls. Anous has
the expansor secundariorum.
Of undoubted or reputed extinct limicolous birds a number
have been described. If Palæotringa (with three species), from
North America, is rightly referred by MARSH to this group, it goes
back to Cretaceous times. Milnea, from French Miocene, is known
by the humerus. Elorius, known by an imperfect coracoid, a tarso-
metatarsus, and parts of the skull, seems to belong here. Ægial-
ornis is considered by LYDEKKER to have been a gull-like bird,
largely on account of the perforated first phalanx of the second
digit. Halcyornis has been described from the extremity of a
humerus and the back of the skull.
-
-.
-
-
.
.
Atlas
Cery. Vert.
Coracoids
Sternum
Nostrils
Basipt. Pr.
Occipital
Foramina
Muscle
Formula
of Leg
1+
10
16
--------
- -- ...--. ..
Charadriiklau Perl.
Distant 2-uotchell | Schiz.
A(B)XY +
Edicnemidæ.1 Notch
Over). 2-notchell Holorli.
(A)BXY +
Parridæ. . Perf.
✓ Overl. 1-110tchell
Scliiz.
ABXY+
Chionidida . Notcli 15 Distant 2-notchell Scliiz.
ABXY +
Thinocoridee.
Perf. 15 Distant 1-notchel Ps.-hol
ABXY+
Glareolide
15, 16Distant 2-10tchec Ps.-hol.
ABXY+
Larida . . Notcli! 15 In cout. 2.110tchell | Schiz. 1-
A(B)XY(+)
--- --- -- ---- ..-... -- .
-- --- ----
"A character which we have seen (supra, p. 351, footnote) to be of no
account in fixing affinities.
I!!!!! +
LIMICOLA
357
The foregoing table shows some of the principal points
in which the several families of the Limicolæ differ from
each other, and will afford a justification for the divisions
adopted in the present work. Whatever is the relation
between the other families, we can clear the ground by
removing the Laridæ from competition for the basal place
in the series. As was discovered by PARKER, the young of
these birds have basipterygoid processes and occipital formina,
the persistence of which, therefore, in the Charadriidæ and
Parridæ (basipterygoids only) places those two groups lower
in the series than the more specialised gulls. That the gulls
are rightly placed here, and therefore as rightly removed from
a closer association with the Alcæ, can hardly be disputed.
GADOW, who does the reverse in his scheme, enumerates only
the following points in which the gulls differ from the
Limicolæ :
In the Laridæ-
Down feathers are thicker. Coracoids in contact. Hæm-
apophyses mostly (not in Lestris) wanting to the dorsal ver-
tebræ. Hypotarsus simpler. In muscle formula of leg dis-
appearance of B instead of Y. Webbed feet.
As a matter of fact, the crossing of the coracoids in
Ediciemus destroys the second of these, at best very slender,
grounds, and, as GADOW admits, the webbing is almost as well
developed in Recurvirostra.
On the other hand the differences from the Alcæ are
more pronounced.
These latter birds have-
A much longer sternum.
Largely developed dorsal hæmapophyses, of which in-
dications only are to be found in the gulls and in other
Limicolæ.
The biceps slip is peculiar.
The leg muscles are always reduced, the formula being
in Phaleris only AX -..
It may be mentioned in addition that the expansor
secundariorum is always absent in the Alcæ and only some-
times in the Laridæ. The auks are, in fact, so far as we
Q
358
STRUCTURE AND CLASSIFICATION OF BIRDS
can see, a further modification of the gull type, but further
from them than they are from the Limicolæ.
We may, therefore, probably regard the gulls as a slightly
inodified offshoot of the typical Limicolæ (Chionis, perhaps,
being slightly intermediate), leading towards the Alcæ. The
arrangement inter se of the remaining families brings us to
the broader question of the affinities of the Limicolæ as a
group. It appears to me that the only other groups which
need be specially considered in this connection are the
Grues, Otides, and Ralli. It may be convenient to preface the
discussion with a tabular statement of the actual points of
likeness between these several groups.
Limicolæ
Cirues
Otides
Ralli
:
14, 15
--
..
--
15-16
14-20 ! 16–18
– or +
Schiz. or hol. Schiz. or hol. ; Hol.
+ or - !
+ or -
1- or 2-notched 1- or 2-notched 2-notched
A(B)XY+ (AB)XY+ BXY +
Hol.
Cerv. vertebra
Basipt. pr..
Nares . .
Occip. foram.
Sternum .
Leg muscles
Patagial fan
Biceps slip :
--
--
1-notched
ABXY+
.
+
+
+ or -
Х
The very difficulty of finding any characters, greatly
noteworthy, in which the groups in question vary is an
index of how closely allied all four are. There can, to my mind,
be no doubt of their common origin. The Limicolæ on the
whole come nearest to the Grues, and especially to the true
cranes, whose distinctive characters are a little swamped in
the above table, owing to the aberrantcranes (e.g. Rhinochetus,
Psophia), whose peculiarities have naturally modified that
table. Taking this point of view, it seems to follow that of the
Limicolæ the most primitive section is that of the Chara-
driidæ proper; for it is among them that the forms with
the greatest number of points of resemblance to the cranes
occur. I should consider these birds to be slightly lower in
the scale than the cranes.
ALCÆ
359
ALCÆ
VLU
Definition.-Oil gland tufted. Aftershaft present; aquincubital.
Skull schizognathous and schizorhinal. Occipital fontanelles
present, but no basipterygoid processes. Two carotids. Ten-
sores patagii and biceps slip distinctive. No expansor secun-
dariorum. Dorsal vertebræ opisthcocolous.
This group of birds comes nearest to the Limicolæ, but
differs more from any of them than they do among them-
selves. The group is entirely confined to the northern
hemisphere, and is mainly Arctic.
The oil gland is invariably tufted and the feathers have an
aftershaft.
In the pterylosis the dorsal tract divides between the
scapula, and there is (? universally) a well-marked spinal
space. But there is no break between anterior and posterior
parts (as in Limicolæ). The ventral tract, contrary to what
we find in the Limicolæ (incl. Laridæ), does not divide early
in the neck. The rectrices (see table, later) vary in number
from twelve to sixteen. The Great auk (Alca impennis) is
said to have possessed eighteen.
The oil gland has often many apertures; there are only
two in Brachyrhamphus marmoratus, but four in Lunda
cirrhata, six in Synthliborhamphus antiquus, and eight in
Uria columba.?
The skull is schizorhinal 3 and schizognathous, with well-
marked occipital fontanelles 4 and impressions for supra-orbital
glands ; the latter nearly meet in the middle line, leaving but
Synthliborhamphus antiquus has only one (the left).
? The remarkable shedding of the beak of the puffin (stated also to occur in
the penguin ; cf. P. 2. S. 1880, p. 2) has been described by BUREAU in Bull.
Soc. 2006. Hr. ii. 1877, pp. 377, 432. See also ibid. iv. 1879, p. 1, for the same
phenomenon in other auks.
3 For osteology of auks see OWEN, · On Alca impennis,' Th. Z. S. v. p. 317;
SHUFELDT, J. Anat. Phys. vol. xxiii.; and PARKER, 'On the Morphology of the
Duck Tribe (Anatide) and Auk Tribe (Alcidæ),' Curringham Memoirs R. Irislu
Ac. No. 6, 1890.
These are sometimes obliterated with age. I find them present in a young
Uria troile, absent in an old one. In a specimen of Fratercula arctica there
was only one present. They also may be present or absent in Brachyrhamphus
and Synthliborlamphus.
LU
ULU
LO
360
STRUCTURE AND CLASSIFICATION OF BIRDS
a thin median line. The interorbital septum is very imper-
fect. Basipterygoid processes are absent in the adult, but
present as rudiments in the young. The lacrymals are
firmly united with the prefrontals, as in gulls and Limicolæ.
The vomer is distinctly double in the young. Alca torda
has an os uncinatum. In Uria troile and in Alca torda and
A. impennis there is on each side a foramen at anterior end
of supra-orbital grooves, as in Chionis, &c. There are fifteen
cervical vertebræ ; the first few dorsal vertebræ have very
conspicuous hæmapophyses, bifid at their free ends. Seven

TRY.
.
.
:
W
'
ST
"
.
-
!.
.1:
-
--
.
d
RS
12
.
2
ST
.
1/III
w a
12III
V
NU
wwwwwwwwwww
www
www
***
e.
.
HUNT
Fig. 173.-TENSORES PATAGII OF Lunda
cirrhata (AFTER BEDDARD FROM FORBES).
(i, slip to ulnar side of fore arm.
FIG. 174.- THE SAME OF Synthli-
borhamphus antiquus.
ribs reach the very long and narrow sternum, which has one
notch on each side posteriorly (Uria), or in addition a fenestra
on each side and a median notch (Fratercula) or no notches
at all (Alca impenris).
As to the muscular anatomy of the auks, the simplest
form of the tensores patagii tendons 1 is seen in Alca torda,
where there are two brevis tendons, both of which pass over
For muscles of Aica {and Spheniscus) see A. CARLSSON, “Beiträge zur
Kenntniss d. Anatomie d. Schwimmvögel,' Bil. K. Svensk. Vet. Ak. Handl.
ix. 1884, No. 3.
ALCÆ
361
mol
-
the extensors of the fore arm to be inserted on to the ulna ;
the anterior of these bifurcates in the limicoline fashion
just in front of its insertion, and here a very faintly marked
fan? (FÜRBRINGER) connects it with the longus.
Synthliborhamphus antiquus is in some respects even
more simple.
: There is but one brevis tendon, from which-just as it
passes over the extensor of the fore arm--the merest apology
for a forward branch exists;
from this branch arises a
special muscular belly of
the extensor metacarpi (cf.
Petrels). There is no
patagial fan, but a special
slip, found in all the other
members of the family (and
also occurring in Larus
argentatus), runs from the
longus tendon to the op-
posite side of the fore arm
to that upon which the
patagial fan, when present,
is inserted.
In Brachyrhamphus
FIG. 175.- TENSORES PATAGII OF Cerato-
marmoratus three separate lina monocerata (AFTER BEDDARD FROM
and parallel tendons arise FORBES).
from tensor patagii brevis muscle, of which the anterior is
the strongest and alone passes to the ulna. From a small
wristward slip arise a few fibres of the extensor metacarpi, as
in the last species. There is no patagial fan, but an ulnar slip,
which gives off a branch running back to the humerus. In
Uria columba there is the same.
In Lunda cirthata there are but slight differences; the
two most anterior of the brevis tendons cross the extensor

.
!
Tartu
VE
NAS
RSS
G
.
· Not figured at all by GARROD in a MS. sketch.
2 For various details in anatomy of soft parts see BEDDARD, 'On the Anatomy
of a Grebe (Æchinophorus major), with Remarks upon the Classification of
some of the Schizognathous Birds,' P. Z. S. 1896, p. 538.
362
AND CLASSIFICATION OF BIRDS
ni
STRUCTURE U
TU
muscles and reach ulna, but they cross it as a single diffuse
band formed by their fusion.
Ceratorhina monocerata has a slight patagial fan, as well
as ulnar slip; otherwise it is like the last.
Fratercula arctica has only two brevis tendons, upon the
anterior of which, at the origin of the patagial fan, is an
ossicle..
The biceps slip is present in Alcidæ, but is generally, if
not always, peculiar. Thus in Alca torda it is inserted partly
on to patagial membrane, partly on to inner of two brevis
tendons (not longus tendon).
In Lunda cirrhata it arises tendinously and joins inner
of three patagialis brevis tendons. The biceps slip (as in
some petrels) is all that is left of the humeral head of the
biceps. io
The biceps slip of Fratercula arctica is inserted on to
middle of three tendons.
In Brachyrhamphus marmoratus the biceps slip ends in
a long and fine tendinous thread, which is inserted on to the
innermost of the three tendons of the brevis.
In Phaleris psittacula the biceps slip is firmly adherent
to the single brevis tendon ; but from it just at the lower end
of the line of the brevis tendon an obliquely running strand
is found, which reaches the tendon of the longus.
The biceps, as already mentioned, consists merely of the
coracoidal head, the humeral head being represented only by
the biceps slip.
The muscle is not large, and in Phalcris its muscular
belly is largely divided into two.
The humeral head of the anconcus seems to be nearly
always present.
There is no expansor secundariorum. The deltoid has,
as a rule, no scapular slip, but there is one in Uria.
The muscles of the leg which are invariably present are
the femoro-caudal and the semitendinosus. The accessory
head of the latter is never present. The ambiens and the
accessory femoro-caudal may be present, and, except in.
? It is (? individually) absent in Brachyrhamphus mclr'moratus.
ALCÆ
363
Phaleris psittacula, are never both absent; the formulæ are
the three following :-
ABX - Uria.
AX+ Ceratorhina.
AX – Phaleris.
The biceps femoris of Brachyrhamphus gives off a fleshy
slip to the outside of the thigh, to the gastrocnemius (cf.
Podica). This slip is not to be found in Phaleris.
The least modified form of syrinx is seen in Alca torda,
The biceps one of the thigh, und in Phale
.


.
U
17)
w
.
MIVUT:111111
01.
9.17
ARI
INI
TH
1.17
ISURE
CO
M
INU
Anel: .
AT
Fig. 176.--SYRINX Or Lomvict
troile (AFTER BEDDARD).
į, intrinsic muscle.
Fig. 177.-SYRINX OY Ceratorhina
Inonocerata (AFTER BEDDARD).
į, intrinsic muscle.
Lomvia troile, Synthliborhamphus antiquus, and Uria
columba.
In Lomvia troile the last four or five tracheal rings enter
into the formation of a three-way piece, which is deeply
excavate medianly. The intrinsic muscles are attached to
the first bronchial semi-ring, which hardly differs from those
that follow ; it and the one which immediately succeeds are
slightly more broad than the rest.
Alca torda is rather more gull-like, there being no
marked depression in the pessulus medianly, and the trans-
parent membrana tympaniformis being sharply marked off
from a thicker yellowish region behind.
36Ł
STRUCTURE AND CLASSIFICATION OF BIRDS
S
Synthliborhamphus antiquus has also a perfectly typical
tracheo-bronchial syrinx, the first bronchial semi-ring (to
which intrinsic muscles are fixed) being longer and deeper
than those which follow. Phaleris is similar.
Uria columba distinctly differs from Lomvia troile (with
which it is often considered to be congeneric), and is an
approach towards a type of syrinx to be described imme-
diately, but with certain peculiarities of its own. .
A dozen tracheal rings in front of the last are very
thin (more particularly in front), and have, therefore, wide
membranous intervals. The last tracheal ring, however, is
stout and ossified; it appears to be composed of two closely
adjoined; posteriorly three rings enter into the formation
of the tracheal box. The first bronchial semi-ring is very
much arched, so much so that laterally it conceals the last
tracheal rings. To it the intrinsic muscles are attached.
In Ceratorhina monocerata this state of affairs is ex-
aggerated. Not only the first, to which muscles are attached,
but the second bronchial semi-ring is very convex upwards,
forming, indeed, the half of a rather elongated ellipse, as
shown in the figure (fig. 177). The last two tracheal rings
are ossified and closely connected. The last twelve tracheal
rings are shallow vertically and leave considerable mem-
branous interspaces.
In Lunda cirrhata there is an almost identical syrinx,
but the last tracheal rings are not particularly thin in front.
Fratercula arctica and F. corniculata are sufficiently
similar to need no special description.
The tongue is generally fleshy, elongated, triangular, and
spiny only at the base.
The relative proportions of the liver lobes not only vary,
but the absolute size of the organ varies greatly.
A gall bladder is always present. There is no crop.
The cæca are usually mere nipples, :35-25 inch in length,
but in Alca torda one inch. The length of the small
intestine in Fratercula arctica is 28.5 inches, in Alca torda
49.5 inches.
From the characters displayed in the accompanying
ALCÆ
365
table it seems possible to divide the group into two families,
Uriidæ and Fraterculidæ, which may be thus defined :-
Uriidæ
Rectrices, twelve 01 fourteen. Lobes of liver equal,
or left larger than right. Muscle formula,
ABX – (or AX-).
Fraterculidæ.
Rectrices, sixteen. Lobes of liver equal, or right
larger than left. Muscle formula, AX+.
Syrinx peculiar.


Accessori
Rectrices Femoro. | Ambieus
caudal
Liver
Lobes
Syrinx
14
Uria colaembe
Synthtiborhamphus antiquus
Ceratorhinc monocerata
Good
Good
16
L>R
L=R
Good
With U-shaped first i
bronchial semi-ring
With U-shaped first
bronchial semi-ring
Lunca cirrhata
.
.
Giood
14
Broach
Brachyrhamphus in armoratus
Phaleris psittacula
tralerculae circtica
A
L>R
L=R
R>L
Slender
With U-shaped first
bronchial semi-ring
I>R
Alca lorda
Uria troile
,
.
.
.
Present !
Good
L>R
There appears to me to be no doubt that the Alcæ are
best placed in the neighbourhood of the Limicolæ, though,
as FÜRBRINGER justly states, “at first sight the relations
between the two groups do not appear to be intimate.'
These differences, however, merely concern outward form, in
which it is perhaps reasonable to compare the auks with
the grebes. But an anatomical study shows plainly that
the grebes are much further away from the auks than are
the Limicolæ. Such points of likeness as there are with the
Colymbi are largely, if not entirely, due to the similar life ;
thus the elongated sternum, which is also shared by the
aquatic ducks, and possibly the muscle formula ABX+.
With the Limicolæ are many positive points of likeness, to
which no such explanation seems to be applicable. In the
skull it is hard to find points of difference; but the most
remarkable point of similarity is the presence in both groups
of those additional tendinous slips upon the patagium on the
366
STRUCTURE AND CLASSIFICATION OF BIRDS
ulnar side (in Charadrius as well as Laridæ) which have been
duly described in the foregoing pages. Nor are there any
salient facts, save such as are evidently associated with loss
of the power of flight, which contradict such a placing.
GRUES
Definition. -Oil gland present and tufted;' feathers with an aftershaft.
Rectrices, twelve. A quintocubital or quintocubital.? Ambiens,
semitendinosus, and accessory always present. Expansor secun-
dariorum present. Cæca large. Skull schizognathous, schizo-
rhinal, without basipterygoid processes. Two carotids.
2
Among the typical cranes of the family Gruidæ I include
not only the nearly cosmopolitan Grus and the African
Balearica, but also the South American Aramus.
There are no particular remarks to be made about the
pterylosis, which NITZSCH states to be precisely like that of
Psophia (see below, p. 374).
The muscular system is fairly uniform in its characters, as
will be seen from the length of the above definition.
The tensores patagii of the demoiselle crane (G. virgo)
are furnished with a muscular biceps slip, which is reinforced
by a tendon springing from the biceps below the origin of the
biceps slip. There is also the usual fibrous junction with
the deltoid crest of the humerus.
From the pectoralis 4 springs a broad flat tendinous slip,
which joins the undivided tensor patagii. The tensor brevis
divides at once into two thin broad diffuse tendons, of which
the anterior sends forward a wristward slip, from whose
junction with extensor metacarpi a slight patagial fan pro-
ceeds to the longus tendon.
In Grus leucogeranos the tensor brevis tendon widens out
shortly after crossing biceps slip into a wide diffuse band,
composed of many strands, but not distinctly separable into
two or three tendons. There is a patagial fan.
| Except in Mesites, Cariama, and Rhinochetus.
? Rhinochetus, Cariama, Psophia.
3 Not in Elypyga.
• The pectoralis I. is usually stated to be single. It appeared to me to be
distinctly double in Grus carunculatus and in Balearica pavonina, especially
in the latter.
GRUES
367
and person who
112 B
Aramus scolopaceus has the same thin diffused tendons ;
but they are distinctly divided below into a main tendon and
a wristward slip. There is no patagial fan.
The anconcus has generally, if not always, a well-marked
broad humeral slip.
The typical formula of the leg muscles for the cranes is
ABXY+. This is the case with all the members of the
genus Grus, excepting G. leucogeranos, where I could find
neither A nor B. In Aramus and Balearica pavonina the
formula is BXY+, and in B. regulorum, as in G. leucoge-
ranos, XY + only. In G. americana the femoro-caudal is
minute and has but a feeble accessory.
The deep flexor tendons are united by a strong vinculum.
Both peroneals appear to be present; but the only notes
at my disposal on this matter refer to G. leucogeranos.
The left lobe of the liver is much smaller in B. pavonina,
a little smaller in G. antigone and G. virgo. The proportions
are reversed in Aramus.
The gall bladder is present; there is a good gizzard ; the
proventriculus is zonary. The following are intestinal mea-
surements:-
021
CONIU
-
-
..
.

-
--
-
-
--
--
Small Int.
Large Int.
Caca
-.
.--.-
-
---
69
Inches
3.5
-
78
--
----
Inclies
Grus antigone
, leucogeranos .
is carunculata . 80.5 ( 3 ) 86(?)
, americana ñ .' 76
en canadensis ő.
72
, australasiana 8 84 (73)
, virgo . . 51.5
Balearica pavonina o 54
, ,, negaton'2/17 0 64
Aramus scolopaccus
7 õ4 9
3.5
3.5
6 (3.5)
Inchies
7 and 8
6.5
8850
7.5
4:25
7.5 (7 and 8:25)
2.5 and 3.25
6.8 and 6.1
5.5
2, 27
--- -------- ----- -
2:5
40
-.-
-
..
.
- .
-
-
.
.
.
.
.
.
.
-
----
-
UUIO
The intestinal coils in the crane tribe are very character-
istic and quite unlike those of any other birds except the
rails and bustards. The figure of Cariama shows the
characters of the Grues generally and may be compared with
that of Crex on p. 323.
The genus Grus has the most typical syrinx. In G. leuco-
geranos the first bronchial semi-rings are firmly attached to
368
STRUCTURE AND CLASSIFICATION OF BIRDS
each other, and the first two are ossified and somewhat arched.
To the first of these are inserted on each side the two flat, rather
broad intrinsic muscles, which run side by side, and which
appear to be continued by fibrous tissue on to the second
semi-ring. There is a normal pessulus. The membrana
tympaniformis gets narrower from above downwards (having,
therefore, a triangular form), and finally ends opposite the
thirteenth semi-ring; but the rings remain semi-rings after
this point, though their ends are very closely approximated,
until close to their opening into the lung. G. australasiana
shows no special differences. In G.canadensis the two mus-
cles, though distinct above, appear to fuse below; they do not
quite reach the bronchial semi-ring as muscle, but are
attached to it by a short ligamentous ending. Grus carun-
culata agrees with the last.
A peculiarity found in many cranes is the convoluted
trachea. This state of affairs is not found in Balearica or
Aramus.
In both males and females of the following species the
trachea is convoluted : G. cinerea, G. antigone, G. carun-
culata, and G. leucogeranios. The males of G. australasiana
and G. canadensis are known to be the same, and the female
of G. americana. In the female of G. leucogeranos and in
the male of G. carunculata the trachea, though convoluted
more or less, does not enter the substance of the sternum, as
it does in the others. This too holds good for Tetrapteryx
and Anthropoides.
The trachea has the usual pair of extrinsic muscles, which
in Balearica pavonina arise not from the costal processes, as
is the rule, but from the angle of the first rib.
I have myself examined syringes of the following species :
Grus canadensis, G. australasiana, G. leucogeranos, G.
carunculata, Balearica pavonina, and B. regulorum.
The syrinx of Balearica is rather different and less
typical.
The two intrinsic muscles are present, but they end in a
See' A Natural History of the Cranes,' by W. B. TEGETMEIER, and Forbes,
P. Z. S. 1882, p. 353.
2
LI
GRUES
369
fibrous band fourteen rings above the end of the trachea.
The first tracheal ring is not so strongly modified as in
Grus.
B. pavonina hardly differs.
There are nineteen cervical vertebræ in G. carunculata,
twenty in Balearica.
Seven ribs reach the sternum in both. The clavicles in
the former and in Tetrapteryx are ankylosed with the sternum,
but not in Balearica. Some of the dorsal vertebræ are partly
ankylosed.
The skull has occipital fontanelles, as in most charadriiform
birds. This holds good also of the slightly aberrant Aramus.
The impressions for the supra-orbital glands are slight, and
largely concealed when viewed from above. The lacrymal
bones do not blend with the ectethmoid. The interorbital
septum is much fenestrated, but not so much so as in the rails.
In Tetrapteryx and Balearica 1 the palatine bones do not
appear to come into contact posteriorly, and at any rate the
inner lamina is continued right to the end of the bone.
This is not the case with Grus, where the bones do come
into contact posteriorly and the inner laminæ are not
continued to the end.
The pelvis of the typical cranes (Grus, Balearica, Tetral-
pteryx) hardly differs from that of such a rail as Aramides.
An outlying member of this group is usually included in
the family Rhinochetidæ. This family is represented by but
a single species, the kagu (Rhinochetus jubatus), of New
Caledonia. The bird is not unlike a heron in appearance;
but BARTLETT, who made a careful study 2 of the habits
of specimens at the Zoological Society's Gardens, compared
its quick active movements rather with those of a crane
than with the slow motions of a heron. The anatomy of
the bird has been chiefly studied by PARKER (osteology),
? So too apparently in Anthropoides stanleyanus (PARKER, T1. Z. S. x. pl.
liv. fig. 6).
? P. Z. S. 1862, p. 218.
3. On the Osteology of the Kagu,' Zool. Trans. vi. p. 501.
BB
· 370
STRUCTURE AND CLASSIFICATION OF BIRDS
רון
MURIE (dermal and visceral structures '),1 and myself
(syrinx and muscular anatomy). Others, however, particu-
larly FÜRBRINGER and GARROD, have contributed details of
importance to our knowledge of this bird.
The powder-down patches, which were originally dis-
covered by BARTLETT, exist as scattered groups of feathers
of the kind; there are not the regular patches found in the
landiilid A

.
.
Wh
..
S1
www.
ORT
www
.
.
.
www
.
www
...
.
C
mm
Fig. 178.–CERTAIN LEG MUSCLES OF Rhinochetus (AFTER BEDDARD).
Si, semitendinosus; d, its accessory; Sm, semimembranosus.
near ally of Rhinochetus, Mesites. The oil gland is present
but nude. The feathers have an aftershaft. There are
twelve rectrices. The pterylosis, imperfectly described by
1. On the Dermal an: Visceral Structure of the Kagu,' Zool. Trans. 'vii.
p. 465.
? Contributions to the Anatomy of the Kagu,' P. 2. S. 1891, p. 9. See also
W. MARSHALL, 'Quelques Observations sur la Splanchnologie de Rhino-.
chetus jubatus,' Arch. Néerl. 1870, p. 402.
GRUES
371
VU
2012
UUUU
LUO
MURIE, has been rather more fully dealt with by FORBES.
The dorsal tract is double on the neck, and continues so
until its termination about on a level with the scapulæ.
The posterior portion of the dorsal tract is not continuous
with the anterior portions; it terminates with a slight bifur-
cation anteriorly and is widely dilated mesially. The ventral
tract is broken into two by the intervention of powder-downs,
and the pectoral branch is perfectly separated from the
main tract, a unique feature, save for Mesites. It is the
scattered powder-downs which are apparently responsible
for much of the breaking up of the pterylæ of Rhinochetus.?
The semitendinosus, its accessory, the femoro-caudal, and
the ambiens are all present in the kagu.
As in Psophia and some other birds, the
semitendinosus is inserted in common with
the semimembranosus. The relations of the
last muscles and of the gastrocilemius are
illustrated in the accompanying figure (fig.
178), which will explain itself. Both pero-
neals are present, and have the typical
arrangement seen when both muscles are
developed. The deep plantar tendons are as
shown in the figure (fig. 179). The flexor FIG. 179.—DEEP
hallucis supplies the hallux alone, and is
7 i FLEXOR TENDONS
tied to the flexor communis by a strong (AFTER BEDDARD).
vinculum before the trifurcation of the
latter. The mode of insertion of the tensor patagiż brevis
is complicated; the tendon divides into three branches,
the two inner of which are prolonged some way beyond the
tendon of the extensor metacarpi radialis longi, to which
they are first of all attached. There is a biceps slip.?
The anconcus longus has a flat tendon of origin from the
humerus, as well, of course, as its scapular head. A muscle
apparently peculiar to Rhinochetus (see fig. 180) is what
has been termed by me an 'accessory biceps.' This arises

OF
12
otuus
In his paper on Mesites, P. 2. S. 1882, p. 267.
2 I wrongly asserted the absence of this in my paper upon the anatomy of
the bird.
B ]} 2
372
STRUCTURE AND CLASSIFICATION OF BIRDS
from the humerus just below the insertion of the deltoid,
and is inserted near to the insertion of the biceps. The
expansor secundariorum is present.
The syrinx of Rhinochetus is tracheo-bronchial, and
presents us with no features of special interest. The
accompanying drawing (fig. 181) shows its lateral aspect.
The bronchidesmus is incomplete ; the intrinsic muscles are
attached to the third bronchial semi-ring.
The number of cervical vertebrce is sixteen. Four of the

-D2
.

L.d.a
Bil
I.d.
!
Bi.a
Fig. 180.- MUSCLES OF FORE LIMB OF
Rhinochetus (AFTER BEDDARD).
D), D2, deltoid ; Lai, La2, latissimus dorsi; Bil, biceps;
Bi2, accessory biceps; N, nerve.
Fig. 181.--SYRINX OF
Rhinochetus (AFTER
BEDDARD).
last dorsal vertebræ are ankylosed. Five ribs articulate with
the sternum. The sternum is unnotched. The skull is
schizorhinal; there are no basipterygoid processes. There
is a partial bony internasal septum not to be found in the
cranes. The interorbital septum is more fenestrate than in
IC
GRUES
373
them. The palatines are abruptly truncated posteriorly, as
in the herons. There are small occipital foramina.
4
.
So
4
.
SS
JEDI
N
2
2
--
inti,
1915
.
1401
Syai
.
.
.
K
AYA
W
SA
.
-
An abnormal member of the crane 2 group is the South
American seriema, of which it is usually considered that there
are two genera, Cariama and Chunga, of the family Cariamidæ.
These birds agree with the cranes
in possessing an aftershaft and in
the number of their rectrices
(twelve). The oil gland, however,
is nude. In the pterylosis (which
has been described by NITZSCH)
there is a marked break between
the posterior forks of the anterior
section of the dorsal tracts and the
anterior fork of the posterior sec-
tion of the same tracts.
The dorsal tract is single on
the neck and divides interscapu-
larly. The posterior parts of the
ventral tract are formed of two 8-
rows about two feathers wide.
Each joins the outer branch above
by one row of feathers merely.
The skull (fig. 182) is des-
mognathous, but the two maxillo-
palatines, though they come into
contact in the middle line, are not
fused. The nasals are appa-
rently holorhinal, really schizo- FIG. 182.-SKULL OF Chunga
rhinal (see p. 144), and there are no VENTRAL VIEW. (AFTER BEDDARD.)
basıpterygoid processes. There are P, palatine ; 6, supraorbital ridge.
fifteen cervical vertebræ ; five ribs articulate with the sternum,
which is one-notched; it has the spina externa.
Stress has been laid upon this fact and comparison, but a posterior trun-
cation of the palatines, nearly as marked, is to be seen in Fraterculae arctica
and not in some other auks.
2 The skull is described by PARKER, Tr. Linn. Soc. (2), i. p. 128 ; the
general osteology and to some extent the visceral anatomy by BURMEISTER,

On
.
.
R
C
TS
4
llllll.wim
VA
>
-
2014
1
WOX
VOLS
w
at.
IM
AM
AUDIN
.
.
.
NA
VVY
GI
.
**.
VIIMANI
2011
.
.
1
WWW
NO.
1
Ibai
III
-
22
AT
.
1
WE
VINTA
3
.
.
VEC
WS
Mahe
CENA
S
11
1
KU
12"
1.4
01
UW
10 .
ins.
374
STRUCTURE AND CLASSIFICATION OF BIRDS
LU
. The muscle formula of the leg is BXY+, as in bustards.
The accessory femoro-caudal muscle (of Chunga) is peculiar
in that it becomes reduced in the middle to a thin tendon,
being muscular at both extremities. Both peroneals are
present.
, The tensores patagii spring from a single muscle. There
is no biceps slip, another point of likeness to bustards. The
brevis tendon spreads out into a broad aponeurosis, but there
is no patagial fan. The anconaus has a humeral head.
The intestinal measurements of the two birds are as
follows:-
Chunga Burmeisteri.
33 inches.
Cariama cristata.
Small intestines, 33 inches.
Large intestine, 3 ,
Cæca,
8.75
3.5
»
8.5 and 10.5 inches.
The family Psophiidæ is represented by the single South
American genus Psophia, including some four species.
These birds have the outer aspect of a rail rather than of a
crane, and PARKER has commented upon their phasianine?
expression of face. Nevertheless their nearest alliance
seems to be with the crane tribe, and perhaps more
especially with Cariama.
The pterylosis has been described and figured by NITZSCH.
There are apparently ten rectrices (not twelve, as NITZSCH
stated), and the oil gland, as in Grus, is tufted. The dorsal
tract is single on the neck and forms a strong bifurcation
between the shoulders; from the two ends of the fork a
single row of feathers descend and unite to form a weakly
feathered but widish posterior part of the dorsal tract. The
ventral tract bifurcates early in the neck, and each in the
pectoral region gives off a strong band on the outside ; the
main portion of each tract is continued on to the cloaca by
Beiträge z. Naturgeschichte der Seriema,' Abhandl. rat. Ges. Halle, i. (1854), p.
17; the viscera also by GADOW, J. f. O. xxiv. (1876), p. 445, and by MARTIN,
P. Z. S. 1836, p. 29. See also BEDDARD, 'On the Anatomy of Burmeister's
Cariama,' P. Z. S. 1889, p. 594, and literature there quoted.
GRUES
375
1/
17
/
.
ht
.
.
a very narrow band of feathers, which is only one feather
wide to begin with, and afterwards only two feathers wide.
The tensor patagii muscles are distinctly gruine ; the
biceps slip is present.
In the hind limb the muscle formula is BXY+, as in
Cariama and the bustards.
The syrinx, shown in the accompanying woodcut (fig.
381), presents no remarkable features. It is quite typically
tracheo-bronchial, and has, as will be observed, an incom-
plete bronchidesmus. It has been stated
(by TRAIL) that the windpipe communicates
with an air space, apparently after the fashion
of the emu. But there is no doubt that this
statement was based upon some imperfection
of the example studied. It has been also
stated that the windpipe in the male is con-
voluted; this requires confirmation also.
The skull of Psophia' is schizognathous Fr. 183._SYRINX
and holorhinal (fig. 81, p. 143). As PARKER OF Psophia leul-
coptera (AFTER
first observed, the orbital margin is furnished BEDDARD).
with about five smallish supra-orbital bones,
a feature which reminds us of certain archaic birds, as the
tinamous, Arboricola, and Menura. The lacrymal has a de-
scending process, which is swollen and nearly comes into
contact with the ectethmoid. The maxillo-palatines are
comparatively large and swollen bones ; as in Cariama
these bones are convex on the outer side, and not concave-
as in Grus. There are no occipital foramina. It may be
remarked that the holorhinal nostrils of this bird show no
such approach to schizorhiny as is displayed by Chunga.
From the anterior part of the maxillo-palatines, on a
level with a point just in front of the commencement of the
bony nostrils, a stoutish knob of bone 2 projects inwards on
either side. Of this there are traces in the cranes, parti-
cularly in Tetrapteryx. If these processes were to be
increased in size and to meet a bony internasal septum, we
F. E. BEDDARD, 'On the Structure of Psophia,' &c., P. Z. S. 1890, p. 329.
2 Duly referred to by PARKER, ' Osteology of the Kagu,' Tr. 2. S. vi. p. 507.

376
STRUCTURE AND CLASSIFICATION OF BIRDS
should have the desmognathous' skull of the American
vultures.
Psophia has seventeen cervical vertebra, of which the

ku
B
TAHUN
ROWNIH
we
PP
...
..
MINUNNI
IRR11
WI
TO
T
2011
**..
umu
TUNUA
-
IT
-
-
-
ACES
w
monitoring
W
N
MATATU
.
2S
!!:
10POL
03
TOINTITO DELLA
elim
Lumir..lent:
le
in
you
ST
W
ii.
22
.
10. Bollisill!
MU
in:33
www
Piniline
INNE
.
..
.
.
.
r
.
.
JU
IML
Wh
.
Ali
WMV
..
.
!
..
... 11
R
...
1272
.
....
.
MU
..
..
.
Shr
IIIIIII
DAM
FIG. 184.-STERNUM, PELVIS, &c., or Psophia leucoptera (AFTER BEDDARD).
CORACOID
!
REMY
PETIT
MLA
WALTERUTZ
D
TAR
...
17TTITO
1.no
DITT.7
0
LA
hotellimus
ST-
Nirmol
he
LC
Ulti
12
-
-
!
w
last bears a rudimentary rib. Five dorsal vertebræ are
ankylosed, there being two free ones behind. The sternum
GRUES
377
(fig. 184) is entire and unnotched; eight ribs articulate
with it.
The atlas is notched for the odontoid process. From
the fourteenth cervical vertebra to the third dorsal there are
blade-like median hypapophyses. In front of the fourteenth
the catapophyses nearly enclose a canal; they get further
apart and die away anteriorly. The following table shows
the number and character of the hypapophyses in various
Grues :-

Chunga
Cariama | Psophia
Rhinochetus
Grus
Balearica
I-
Catapophyses Last on C11
012
013
Cli
015
C16
Hypapoplyses C12-D1
C13-D1
C14-D3
012-D3
C16-019
C17-019
11
The family Eurypygidæ contains but one genus and
species, Eurypyga helias, native of South America. It has
an oil gland, which is generally nude but occasionally tufted,
and twelve rectrices. Eurypyga, like Rhinochetus and
Mesites, has powder-down patches, but their arrangement is
very different from those of Rhinochetus. Dorsally there is
on either side of the dorsal tract a compact dense triangular
patch; in front it continues over scapula as a band which
runs on to the sternal surface, and there forms a sparsely
feathered patch more or less continuous with pectoral tract
of contour feathers. There are a few scattered powder-
downs on axilla and along neck.
The tensor patagii brevis is broad and rather diffused,
stronger at the two edges; it sends off a wristward slip.
The tensor longus is reinforced by a strong biceps slip.
The expansor secundarioruin is strong and 'ciconiine.'
The anconcus has a humeral attachment. The insertion of
the deltoid extends halfway down the humerus. I have
noticed in the pectoralis primus a vertical septum dividing
the muscle into a right and left half.
The muscle formula of the hind limb is complete, i.e.
ABXY+. The glutæus I. extends well over the biceps.
Both peroneals are present.
378
STRUCTURE AND CLASSIFICATION OF BIRDS
The liver is equilobed, with a gall bladder. The intestines
are 18 inches long, the short cæca (4 inch) being 14 inch
from cloaca.
Both carotids are present.
The skull of the sun bittern has been described 1 and
figured by PARKER.
It presents several points of likeness to that of Rhino-
chetus, notably in the ardeine character of the palatines,
which are cut off squarely behind and are of approximate
length throughout; each palatine, moreover, has a fenestra,
as in Tigrisoma leucolophum (and also in Numenius phcopiis
and Anous stolidus). The interorbital septum is widely
fenestrate; there are no occipital foramina. As in Psophia
(q.v.), Rhinochetus, and cranes, there is a rudimentary "snag'
from the anterior part of maxillo-palatine.
The nostrils are schizorhinal, and the curves of the
various surfaces of the bones are such that if the very
narrow anterior chink were closed a well-rounded and quite
typical holorhinal skull would be the result.
Eurypyga has a one-notched sternum with well-developed
spina externa. There are eighteen cervical vertebræ, and
three dorsals are fused.
The pelvis is a little less rail-like than in Grus, Rhino-
chetus, Psophia, &c., in being wider, and in the more hori-
zontal plane of ilia, which do not meet.
Family Aptornithidæ.3—The two species of Aptoris, A.
defosson and A. otidiformis, from New Zealand quaternary
deposits, were originally referred to the Dinornithidæ, and
more lately to the rails. FÜRBRINGER has, however, advanced
certain reasons for relegating them to the neighbourhood of
Rhinochetus, and I follow him in placing them in the present
group. The chief reason which persuaded FÜRBRINGER to
this conclusion was the schizorhinal nostrils, quite evident
ToOn the Osteology of the Kagu,' Ir. 2. S. vol. vi., and On Ægithogna-
thous Birds, ibid. vol. X. p. 307, pl. liv. figs. 7, 8, 9.
? See, however, footnote, p. 373.
3 OWEN, 'On Dinornis,' pt. xv. Tr. Z. S. vii. p. 353.
GRUES
379
in OWEN's plates, and showing the inward curvature so often
found in the schizorhinal nostril, and quite apparent in Grus
(though not in Rhinochetus). A special point of resemblance
to Rhinochetus among the crane-like birds seems to me to
be in the partial ossification of the nasal septum. The
solidity, posteriorly at any rate, of the interorbital septum is
like Psophia so far as gruine birds are concerned, while the
spout-like process, upwards of the palatines is quite in
harmony with FÜRBRINGER's views of the affinities of Ap-
tornis. The junction of the zygoma with the post-frontal
process is not crane-like ; it occurs among gallinaceous birds,
and there is a near approach to it in Otis.
In the view given by OWEN of the under surface of the
skull is a bone described, though not figured, which ap-
pears to me to correspond to the desmognathous palate of
Cariama. The union of the bones and their divergence
posteriorly are precisely like what is to be seen in Cariama.
Large basipterygoid processes are present, but OWEN
failed to find upon them an articular surface.
So that while the outline of the skull of Aptornis is very
like that of some of the large rails its affinities have been
probably more correctly diagnosed by FÜRBRINGER.
Besides the Aptornithidæ already mentioned other forms
referable to the Grues have been obtained from Tertiary
strata. Of these Aletornis (with a number of species) is placed
among the Gruidæ and Geranopsis of LYDEKKER. The latter
is known only by the coracoid, which differs somewhat from
that of Grus. LYDEKKER does not admit the genus Palæogrus of
PORTIS.
The family Mesitidæ is represented by the Madagascar
Mesites, a genus containing but a single species, which has
been investigated anatomically by MILNE-EDWARDS 2 and by
FORBES. One of its principal characteristics was originally
| Loc. cit. pl. xl. figs. 1, 2.
2. Remarques sur le Genre Mesites,' &c., Ann. Sci. Nåt. (6), vii., and in Hist.
Nat. de Madagascar.
3 . Description of the Pterylosis of Mesites,' &c., P.Z. S. 1882, p. 267.
380
STRUCTURE AND CLASSIFICATION OF BIRDS
discovered by E. BARTLETT, who found and described
briefly the powder-down patches.
The bird has sixteen rectrices, and apparently—but there
is some little doubt about the matter—a nude oil gland. The
contour feathers have no aftershaft. There are five pairs of
powder-down patches. The most anterior pair lie in the
interscapular region, and are enclosed by the dorsal tracts.
The second pair are upon the rump, the third pair at the
commencement of the pectoral region; the fourth pair lie
also on the ventral region, but posteriorly ; the fifth pair,
finally, are axillary. The number of these pairs is greater
than in any known bird, and their definition and complete
separation as distinct patches contrasts with the diffused
arrangement characteristic of Rhinochetus and Eurypyga.
There are four apteria on the neck, since both dorsal and
ventral tracts divide early. The dorsal tracts converge inter-
scapularly, and then become much feebler, and are continued
on to the Y-shaped posterior part of the tract. The ventral
tracts cease altogether at the commencement of the pectoral
region, but recommence behind the powder-downs. The
outer branch is present, but is quite unconnected with the
main stem.
The muscle formula is complete, ABXY+. Both carotids
are present.
As FÜRBRINGER removed Aptornis from the rails and
placed it in the present group largely on account of its
schizorhinal nostrils, it is remarkable that he did not also do
so with the present bird. The bony nostrils are, in fact, of
the type that has been termed pseudo-holorhinal. They are
rounded at their end, but elongated and curved inwards ; they
are exactly like those of Glareola.
Mesites is schizognathous, with delicate maxillo-palatines.
The descending process of the lacrymal abuts upon, but
does not fuse with, the very stout square ectethmoid. This
part of the skull, again, is more like Glareola than any gruine
form ; but it is also like Pterocles and various other birds.
There are seventeen cervical vertebra, and four ribs reach
I 'Remarks on the Affinities of Mesites,' P. 2. S. 1877, p. 292.
GRUES
381
the one-notched sternum. The dorsal vertebræ with com-
plete ribs are ankylosed. The furcula is quite degenerate.

Aftershaft
Oil Gland
Poider-downs
Fifth Remex
Nostrils
1 Occipital Fontan.
Supra-orbital
Grooves
Interorbital
Septum
Cervical
Vertebræ
Dorsal Vertebræ
fused
Sternum
Muscle Formula
of Leg
Biceps Slip
+
O
idæ
++
Gruidæ . . + Tuft o oi Schiz. + + Incompl. 19, 20 2–3(4)"| Solid ABXY+ +
BXY+
XY +
Cariamidæ
Nude 0 + 10.10 Compl. 15 None Oue BXY+
incis. XY+
Rhinochetidæ.
N.
Schiz.
Incompl. 16 1-4 Sol. LAXY +
Eurypygidæ . + N., t. |
Scliiz.
Incompl. 18 1-3 One ABXY +
incis.
Mesitidæ
Schiz.
Incompl. | 17 | 1-4
One ABXY +
incis.
Psophiidae ..
Hol.
Sol. BXY+
RALLI . .
Incompl. 15,14 | None ABXY +
incis.
OTIDIES. .lt 010 010 Incompl. | 16, 17 None Two BXY+ o
iucis.
CEDICNEMIDÆ. + ' T. OloHol. Tolo Incompl.16 None Two ABXY+ +
incis. BXY +
+ + oo Ot
+ + + o
tt O
Fol.
"Not completely fused, and not always.
It is clear from the accompanying table that the seven
families which I here include with the Grues are a tolerably
divergent series of birds. Yet it does not appear to me
possible to locate any one of them elsewhere. The bird
concerning whose position I am most doubtful is naturally
Mesites. It is placed near the hemipodes among the galli-
naceous birds by GADOW, and by FÜRBRINGER near the
hemipodes but among the rails. SHARPE takes the view
which is urged here, while FORBES and some other recent
writers are impressed by its likenesses to Eurypyga and
Rhinochetus, FORBES, indeed, having associated all three in
a separate group. There are, unfortunately, so many lacuna
in our knowledge of this form that a strict comparison is as
yet hardly possible. Allowing the characters of the deep
flexor tendons, not mentioned by FÜRBRINGER, the agree-
ments with the Turnices do not appear to me to be more
numerous than those with Eurypyga, while the powder-
bird.
There are difficulties too with other genera of crane-like
382
STRUCTURE AND CLASSIFICATION OF BIRDS
birds. For PARKER the inclusion of Cariana in the present
group is impossible. Yet I find myself in this matter in
accord with most recent writers. If Cariama is not allied
to the cranes, where are we to put it? The only alternative
seems to be the rails, which are in any case not far removed
from the present group. MITCHELL has pointed out the
very close resemblance in the intestinal tract of cranes, rails,
Cariama, Otis, and (as yet unpublished) Psophia. PARKER,
on the other hand, has emphasised the likeness between
Cariana and the Accipitres, a likeness which has even im-
pressed itself upon their external physiognomy. FORBES
went so far as to include in the same group with Cariama
the secretary bird. It appears to me, in fact, that the
origin of the Accipitres is to be traced to some crane-like form,
and that the very varied characters of the Grues point to
their being a basal form connected with more groups than
one. As is pointed out elsewhere, unless we are to regard
the Accipitres as here treated as diphyletic, or even triphy-
letic, we must assume that the Catharta and Serpentarius
are the most primitive forms whence the typical Falconidæ
have been derived by a loss of two muscles of the leg. In
these birds the formula BXY or AXY must come before A
alone. But little change is required to convert Caricma into
Gypogeranus ; and if it be objected that this is because
Cariana is an accipitrine, the quite similar skull, so far as
the desmognathism is concerned, of Aptornis may be pointed
to; it will hardly be contended that Aptornis is anything but
a crane or a rail. Along another line probably the peculiar
desmognathism of the American vultures may be derived
from conditions obtaining in the crane group. PARKER has
pointed out the ossification and fusion in the middle line of
alinasals in Cariama ; but in that bird the fused bones, though
quite analogous with, cannot be the exact homologues of,
the fusion of bones which has occurred in Cathartes, &c.;
for the position is totally different, being much further
forward in Cariana. There is, however, in Psophia and in
others of its allies—particularly well developed in Psophia-
''A raptorial isomorph of the Cranes' (PARKER).
GRUES
383
a small snag of bone, already referred to as projecting out-
wards from the maxillo-palatine in precisely the spot required;
if this projection were to grow more extensively, we should
have a palate exactly like that of Cathartes and Gypagus.
To consider another quite different group of birds, the
Herodiones, I have urged on another page (p. 441) the low
position of Platalea among the Herodiones. In more than
one particular these birds recall the cranes. The occipital
fontanelles, the complete muscle formula are among these
characters. FÜRBRINGER has hinted at, but not accepted,
the diphyletic origin of the Herodiones ; were it not for Scopus
and Balæriceps, this might be fairly assumed indeed; and in
view of this possibility the strongly ardeine character of the
palatines in Rhinochetus and Eurypyga may be commented
upon. This character, too, is coupled with the existence of
powder-down patches.
Though the charadriiform birds form, in my opinion, a
group distinct from the Grues, there are many points of simi-
larity between them. This is practically shown by the fact
that Edicnemus has been much bandied about between the
two groups. The occipital fontanelles, the supra-orbital
impressions are among the points of likeness. In view of
these facts the likeness in some matters of the skull of
Mesites to that of Glareola is perhaps significant. It is
really mainly the form of the intestinal coils as described by
MITCHELL that leads me to dwell upon the separateness of
the two groups. But this question is dealt with more fully
under Limicolæ con p. 358).
As an appendix to the Grues we may perhaps consider the
STEREORNITHES
This singular group of birds was originally discovered in
the lower Tertiary strata of Patagonia by the well-known
palæontologist AMEGHINO. Of the several genera assigned
to the family, many of which are very imperfectly known
See, however, p. 373 footnote, where a similar conformation of these bones
in the auk, Fratercula, is described.
384
STRUCTURE AND CLASSIFICATION OF BIRDS
and doubtfully referable to the group, Phororhacos is the
best known, almost the entire skeleton being now in the
museum at Buenos Ayres. A convenient summary of AME-
GHINO'S work, with criticisms, has lately appeared in the 'Ibis,'2
by Mr. ANDREWS, from the whose paper the information here
has been extracted. When first discovered (the anterior por-
tion of the lower jaw) the creature was referred to the mam-
malia. As with the leg bone of the Dinornis its ornithic
nature was doubted, though the lesson afforded by the
Dinornis might have tempted naturalists to be bolder than
was perhaps reasonable in the forties. The bird was formerly
CD

.
.
A
X
W
.
10
.
:*
.
>
..
.
.
*
11. F
S
.
11W
.
9
ESOS
1KO
OM
V
pun
:*
SK, NY
WISAP
.
NA
450..
.
W
UN VOYED
7
DAWA
ay NGO
HIV
.
4*
$
1.
SA'
MORE
.
1
:*:
SEE
24
AVE
:
*
OUT.
.
.
TAYO!
SOS
IKA-
.
V
Po
06
.
ti
usu
1
O
SIS
O
ES
'
DOS
.
QuotUA
::r
.
***
TA
NOW!
**US
S
Vr
.
D
GER
SUNT
.
00
XO
ka
.
*
AX
1
"
...
IS
:1.
.
SOWE
.
SARAN
3.SE
1.
1X
...
r
.
.
.
Di
KO
Vrat.
..NY
-
..
.
.
4
RA
.
.
*
-
.
PU
im
VAN
1
it
:
OneWALTOVA
SA
WAX
VIVO.
.
A
OM
ke
TI
HYFFITI
IV
.
.
.
.
1
.
.
.
CH
KY
.
A
O
1
WIN
M
MONOL
11
SUNT
NYA
T
-
.
H
.
:
KOOL
1
.
ORLU
ori
MOS
13
VO
.
.
Til
VXXU
DUITS
NITA
1-tit
LOV
AXA
19
I
LIS
Ici
.
I
KUS
...
YOYO
.
hiv
..
..
,
.
.
..
.
.
.
VA
..
.
27
0
.
CS
WE
9
2
.
.
NA
.
.
YOY
.
..
NA
ASSY
.
.
Menu
.
.
NA
Oo.
AK
PART
12:10
. * . .
ON :
Wir
UUTA
Fig. 185.-SKULL or Phororhacos. LATERAL ASPECT.
(AFTER ANDREWS.)
held to be ratite. But LYDEKKER, who examined the qua-
drate, found that, as in carinates, it articulated by two heads
instead of the one which characterises that bone in the
ratites.
The skull of Phoror hacos longissimus is two feet in
length; the hooked beak has two or three serrations at the
commencement of the hook, which remind one of the Eocene
Odontopteryx, in which bird, however (see p. 418), the serra-
tions extend along the entire length of both jaws. Seen
from above certain resemblances between this skull and that
of Phalacrocorax or Piotus will be apparent. ANDREWS
thinks that the lacrymal was united with the jugal by a
E.g. Brontornis, Dryornis, Pelecyornis.
2 Jan. 1896.
3 Except Apteryx.
STEREORNITHES
385
1
.
.
.
r
.
141
"
.
ya
US
nes
..
IGRO
6.
22
si
x2
zł
.
11
?.01.
SABT26
UK2
.
.
O
UN
.
Poi
* NO
NIYA
XXX
.
trẻ,
OTIV
O
01
.
ON
NICAR
E ran..
.
:
.
12
:
.
*
1
.
A
.
separate bone which exists in Cariama (and of course
Chunga), a bone which is found in other birds, though its
articulation with the palatines often makes its identification
with that of the seriema doubtful.
The ventral surface of the skull is crane-like.1
The vertebral column is interesting on account of the
fact that many of the dorsal and all
of the caudals have their centra per-
forated for the remains of the noto-
chord. There is no pygostyle. The
pelvis is remarkably like that of Hes- .
perornis and the grebes. It has the
length and narrowness of that limb
girdle in the birds mentioned. It
has, however, been more satisfac-
torily perhaps compared with the
pelvis of Cariama. The slenderness
and length of the coracoid, together
with the absence of a procoracoid,
prevent a comparison in this particu-
iar with the ratites. It is typically

NIN
9
TRA
*
F!
*
oW:
ARR
.
NOVA
NA
**
Sv
.
.
MATE
C
N1
dra
...
19
WRIT
*.
17
FOWA
with
YOU
K
LY.
PA
YOY
.
dal
ON
.
YO
2
.
FOTO
.
Nr.
cu
4
1
2M
T
TU
.
.
st
.
.
22
1
'
.
UMNO?
.
X4in.
..17
.
..
.
.
wy.
IZ
.
..
.
CS
4
"
22
KI
2747.
.
**
C2
.
EV
A
.
.
KOV:
re
in
K
...
14
.
.
A
nen
Vn
.
.
YU
L
*
.
A
3
..
2./
.
.
TO
MOTO
C.RO
tar
S
..
VIVA
S
.
s
"W
'
SAN
CO
.
. .
11.
SOSY
m
.yr
RM
MON
*
WS
S
TATUS
1,
.m
!
.
'
Y
NN
.
cenu
.
S
.
..
.
WWW.
Si
..
.
.
Vies
XII
nes
.
1
AM 12
.
Yes
2.
-
Ut
.
.ASTO
'.
inson
.
.
asive
OY
ucre
A
ou.
L
10.
h
CA
FIG. 186.—SKULL OF P1ro-
rorhacos. DORSAL ASPECT.
(AFTER ANDREWS.)
FIG. 187.-PELVIS OF Phororhacos. DORSAL
ASPECT. (AFTER ANDREWS.)
22
UU
carinate in fact, and shows perhaps special resemblances to
Cariama.
The ulna shows well-marked tubercles, which indicate the
insertion of the secondaries. Though reduced in size, and
therefore possibly useless for purposes of flight, it seems
i See letter from Dr. GADOW, Ibis, Oct. 1996, p. 586, where it is pointed out
that Stereornis is synonymous with Pliororlacos, and that therefore the name
Stereornithes cannot stand. It is, however, difficult to compose a name out of
Phororhacos, and it is not proved that the birds in question are definitely
cranes. I therefore leave the name.
C C
386
STRUCTURE AND CLASSIFICATION OF BIRDS
likely that the wings of this bird were more efficient than
those of the ratites on account of the apparently well-
developed remiges.
COLYMBI
Definition.-Oil gland tufted. Aftershaft present. Aquincubital.
Accessory semitendinosus absent. Biceps slip present. Glutæus
maximus large, extending behind acetabulum. Cæca long.
Skull holorhinal, without basipterygoid processes, schizogna-
thous. Tibial crest strongly developed.
This group of birds contains two very well-marked families,
the divers (Colymbidæ) and the grebes (Podicipedidae). In view
of their numerous and important points of similarity I have
not thought it desirable to separate these two families quite
so widely as has GADOW. The Colymbidæ contain but one
genus, Colymbus, with four species. Of the grebes there is
perhaps also only one well-marked genus, Podicipes. But
the Central American Centropelma (of SCLATER and SALVIN)
has some claims, on account of the complete loss of flight, to
generic distinction, while in the course of the following pages
it will be seen that there are certain, if small, reasons for
distinguishing Æchmophorus and Tachybaptes. Podilymbus,
another alleged genus, has not been dissected.
Our knowledge of the anatomy of this group of birds is
chiefly due to NITZSCH,' BRANDT, 2 COUES,3 SHUFELDT,4 and
myself.5
As to external characters, there is a close agreement
among the Colymbi. The number of rectrices in Colymbus
glacialis I find to be twenty. NITZSCH gives eighteen to
twenty for the genus. Specialised rectrices are not recognis-
able among the grebes. The inferior tract of feathers is
I Loc. cit.
2 • Beiträge z. Kenntniss d. Naturg. d. Vögel,' Mem. Ac. St. Petersb. 1840,
p. 197.
3. On the Osteology of Colymbus,' &c., Mem. Bost. Soc. Nat. Hist. i. 1866,
p. 131.
+Concerning the Taxonomy of the N. American Pygopodes,' &c., J. Anat.
Phys. 1892, p. 198.
5 Notes upon the Anatomy of a Grebe (Æchmophorus major),' &c., P.Z. S.
COLYMBI
387
divided into two about halfway down the neck; the two
tracts are not again divided upon the trunk, where they are
broad. The spinal tract divides high up on the neck (Podi-
ceps cristatus) or only between the shoulders (Colymbus
glacialis). The anterior part of the spinal tract is stronger
than the posterior part, and is separated from it; the latter is
solid, enclosing no space.
The patagial tendons of Colymbus glacialis are rather
simple. The tendon of the brevis is a rather broad undivided
band. There is no patagial fan, but, as in Æchmophorus, a
delicate tendon arises from the fore arm near the insertion of
the tensor brevis and ends in the biceps slip. In Colymbus
arcticus, according to FÜRBRINGER's sketch, a broad diffuse
tendon arises from biceps slip, and ends freely upon the
patagium. The first description given is from my own dis-
section of C. glacialis, and agrees with a manuscript note
of Mr. FORBES upon C. septentrionalis. But C. glacialis
apparently sometimes approaches C. arcticus. I have a manu-
script sketch by Professor GARROD showing a broad band of
fibres arising from the biceps slip, but ending on the fore arm.
The anconcus has a humeral head. The expansor secun-
dariorum appears to be absent. The biceps is single-headed.
The leg muscle formula, in contradistinction to what we
find in the grebes (where it is BX - ), is ABX +.
There is a peculiarity in the gastrocnemius of C. septen-
trionalis which is worth calling attention to : one of the heads
of that muscle arises from the tendinous end of the glutæus
maximus.
The femorocaudal is tendinous for half its length; its ac-
cessory is a very large muscle. The ambiens in Colymbus
glacialis has two heads of origin.
The combined plantar tendons give off a small slip to the
hallux in C. septentrionalis, as in Podicipes minor.
The divers have two carotids, the more modified (cf. leg
formula) grebes only the left.
The lobes of the liver in the Colymbi are equal, and there
is a gall bladder.
The following are a few intestinal measurements:
сс 2
388
STRUCTURE AND CLASSIFICATION OF BIRDS
-
-
-
-
-
-
-
-.
.
S. I.
L. 1.
Cæca
. .
.
--
.
-
-
-
-
-
Inches
1:7, 1:8
-
-
-
-
Columbus septentrionalis
glacialis
Podicipes cornutus .
o mninor . .
Ft. Ins.
3 11
5 4
2 5
2 5
Inchies
3.7
2.5
1.5
1.5
1.1, 1.6
1.5
-
-
-
-
--
-
-
--
-
.
..
-
-.
.
.
-----
The cæca of C. septentrionalis are conical and saccular in
form, with irregular but distinct transverse rugæ.
The syrinx in the divers (Colymbiis septentrionalis) is not
in any way remarkable in form. The last tracheal rings and


.
Ro
படம்
.
All
AU
i
Piumin
Williini
SS
EEZ
millilijiinit
T
SINUL
WWW.
l
.
.
AN
1
"
WWIIN
III
LAI.
FIG. 188.-SYRINX OF Æchmopliorus.
į, intrinsic muscles.
Fig. 189.-SYRINX Or Tachybaptes.
i, intrinsic muscles.
the first bronchial are ossified and firmly attached to each
other. The pessulus is also ossified. The succeeding bron-
chial rings are soft and cartilaginous. The powerful intrinsic
muscles are inserted partly on to the last tracheal ring and
partly on to the first bronchial, the line of insertion being
oblique.
The syrinx of Æchmophorus (fig. 188) has a very incom-
plete bronchidesmus, a very wide space between the two
bronchi existing above its anterior edge. The last two
tracheal rings are fused to form a long box, into the compo-
sition of which it appears to me that the first bronchial semi-
ring enters. In any case, if that be not so, the first bronchial
Y
COLYMBI
389
semi-ring has the unusual relations shown in the drawing,
which are perfectly consistent with the belief that the ring is
the second bronchial. The intrinsic muscles are attached to
the third tracheal ring in front of the tracheo-bronchial box.
The bronchial semi-rings are fairly ossified, but have rather
wide membranous interspaces.
In Podicipes cristatus there is the same failure of the
intrinsic syringeal muscles to reach even the end of the
trachea. A box is formed by fusion at the end of the trachea,
into which it appears to me the first bronchial semi-ring does
not enter. The bronchial semi-rings are deeper and closer
together, and the whole bronchus is more ossified, than in
the last genus. The bronchi, too, are longer.
In Podicipes cornutus the syrinx is much the same, but
of course smaller. The first free semi-ring of the bronchus
seems to be No. 2. There is a wider membranous interval
between it and the antecedent tracheo-bronchial box than in
the last species.
Tachybaptes fluviatilis (fig. 189, p. 388) has a different
syrinx. The last three tracheal rings are only fused in front,
though they are closely united laterally. These rings are
much ossified. The insertion of the intrinsic muscles is
remarkable. They run obliquely forward, converging, to be
inserted into the last three tracheal rings. The first bron-
chial semi-ring is arched, and ossified in front, where it is
fused with the tracheal box; otherwise it and the succeeding
rings are cartilaginous. It is clear, therefore, that the
syringeal characters justify the generic distinction here
adopted.
The cervical vertebre are more numerous in the grebes
than in the divers; they are only fourteen or fifteen in the
latter, twenty-one in Æchmophorus and Podicipes cornut-
tus. Cervical vertebræ 10 to 16 in Æchmophorus I have
a catapophysial canal; on 17 and 18 the hypapophyses
are blade-like and enormous; these processes extend to
the very end of the dorsal series. The last cervical and
the first three dorsals are fused. There is no catapophysial
A canal is nearly formed in Podiceps.
O
390
STRUCTURE AND CLASSIFICATION OF BIRDS
canal in Colymbus ; but the hypapophyses are greatly deve-
loped, and in the dorsal region Y-shaped, with widely diver-
gent flattened and expanded limbs. None of the dorsal
vertebræ are fused. Six ribs reach the sternum in the two
grebes mentioned ; eight or nine in the divers. The sternum
is one-notched; in the grebes it has in addition a median
triangular notch. There is no anterior spine to the sternum
in the grebes. The procoracoid is moderately large and
hooked in the divers, absent in grebes. The pelvis is very
elongated and compressed, as in Hesperornis, but the ischia
are not free from the ilia, as in that bird.
In the skeleton of the leg the most conspicuous feature
is the highly developed cnemial crest. The patella too is
very large in the grebes, but not in Colymbidæ, where, indeed,
it is not ossified. In these particulars the grebes resemble
Hesperornis. The principal skull characters have been
already mentioned in the definition of the group. In addition
to these matters the strongly marked temporal fossæ may be
mentioned, which nearly meet on the upper surface of the
skull. They are not so well marked in the small Podicipes
minor. In the divers are strongly marked furrows for the
supra-orbital glands; this is not the case with the grebes.
The former have also a single median occipital foramen
above the foramen magnum. The ectethmoids exhibit the
bullate form so characteristic of the Anseres.
It may be useful to state in a tabular form the principal
characters of the grebes and divers.!
Muscle
Tormula
Carotids
Cerv.
Vert.
Dors. Vert.
No. of 1 Semi-
Conn. I men bril-
Ribs
NIOSIIS
Grebes
Divers
l
.
.
BX-
ABX +
1
1.2
.
21
15
! Ankylosed !
Not ank.
4-6
8,9
+
-
-
-
-
-
-
-
.
.
.
These characters appear distinctly to point to the more
modified structure of the grebes. There are reasons (p. 165)
for regarding a small number of cervical vertebræ and a
O
| The extinct Colymboicles (C.minutus, M.-E1). ; C. anglicus, LYDEKKER), of
which the former is known by a humerus, the latter by a coracoid, and possibly
a piece of sternum, is said to combine the characters of grebes and divers.
COLYMBI
391
large number of complete ribs as more archaic characters
than the reverse ; the other features as evidence of degenera-
tion require no comment.'
In considering, then, the affinities of the Colymbi the
Colymbidæ are to be chiefly taken into account. But any
comparisons bristle with difficulties. The late Mr. FORBES
in his final scheme of classification definitely associated the
Colymbi with the Heliornithidæ; in this course I supported
him by reason of certain muscular characters of both groups
of birds. The outward appearance, too, of both birds is not
at variance with such an affinity. The muscular formula of
the leg is the very unusual one of ABX+. This reduced
formula is found in Podoa and in the Sphenisci, Anatidæ,
Tubinares, Phalacrocorax, and certain Alcidæ. It is to be noted
that all of these are at least largely aquatic in their habits, a
fact which must, of course, discount the value of the character ;
but still ABX is an unusual formula, and there are other
grounds for regarding the birds mentioned (with the excep-
tion, perhaps, of the Alcidæ) as having some relation to each
other. The insertion of the biceps slip on to the patagium
allies Colymbus and Podoa; though this also occurs in other
birds, it is, again, in some that are presumably not far from
the Colymbi : for example, of the forty characters selected
by GADOW for the comparison of the various groups of birds
the Colymbidæ agree with the Sphenisci in twenty-eight;
with the Tubinares in twenty-seven ; with the Steganopodes in
twenty-six; with the Anatidæ in twenty-three ; with the
Heliornithidæ in twenty-three.
On the other hand there are twenty-five points of likeness
to the Larida, as deduced from the same tables, and no less
than twenty-nine to the Alcæ. As might indeed be imagined,
it would be rash to lay much stress upon the proportions of
these numbers. It is not to my mind clear with which of
the groups mentioned the Colymbi are most nearly allied.
Their undoubted relationship to the Hesperornithes is treated
of on another page (p. 395); and it is perhaps this very fact
which prevents us from detecting likenesses to more modern
(?) groups.
392
STRUCTURE AND CLASSIFICATION OF BIRDS
HESPERORNITHES
Definition.-Large extinct birds of a diver-like form. Skull holorhinal,
with supra-orbital impressions. Vomers paired. Quadrate
single-headed. Sternum without keel. Shoulder girdle platy-
coracoidal; clavicles fully developed. Fore limb represented by
humerus only.
!
The principal source of information concerning the
remarkable genus Hesperornis, from the Cretaceous of North
America (to which three species, viz. H. regalis, H.crassipes,
and H. gracilis, are assigned), is naturally the magnificent
treatise on this bird (and on Ichthyornis) by MARSH."
The bird stood about six feet high, and presented the
general form of the diver, to which bird it is now held to
come nearest. MARSH, however, compared it more especially
with the Struthiones, and it is spoken of by him and by
others as an 'aquatic ostrich.' The former view now holds
the field.
There are, nevertheless, various struthious features in
the skull, and in other parts of the skeleton, some of
which may be held to be due to its loss of the power of
flight; others are not so explicable from the point of view of
our actual knowledge of bird structure.
The skull has the general contours of that of the diver,
and, like that bird, has very well-marked furrows for the
supra-orbital glands. The nasal bones produce a holorhinal
nostril. The figure given by MARSH of the upper surface of
the skull is a little suggestive of there having been an ap-
pearance of the ossified ethmoid on the surface of the skull,
as in some struthious birds and tinamous. The interorbital
septum is fairly ossified with a large foramen. The lacrymal
is large with a large descending process, which nearly, if not
quite, reaches the jugal bar. The pitting of the premaxil-
laries led MARSH to the inference that the beak was present,
in addition to the teeth, which will be presently referred to.
The skull has been described as “saurognathous,' on
i Odontornithes. Washington, 1880.
HESPERORNITHES
393
account of the paired vomers. These were, however, not
particularly like the presumed. vomers of the woodpeckers
(see p. 187). Each bone is broad behind, where it may, as
in struthious birds, have articulated with the pterygoids, and
tapers in front to almost a point. It is not clear whether
the bird really had, as MARSH is disposed to infer, a 'dromæo-
gnathous' palate. In any case the basipterygoid processes
are present, and the articulations on the pterygoids are
towards the posterior end of these bones, as in the skull of
the Struthiones. The palatines are longish bones, and are
compared to those of the ostrich. They taper in front. As
in most Struthiones the articular head of the quadrate, for
articulation with the skull, is not divided into two facets.
The rami of the lower jaw do not appear to have been
ankylosed together, but to have been connected by a possibly
merely chondrified or ligamentous tract, which would have
allowed a gaping of the mandibles —seen partly in the
pelican, and obviously useful to a fish-eating bird, as we
may presume Hesperornis to have been. Both lower and
upper jaws have teeth, which are implanted in a continuous
groove, widened at the implantation of each tooth. In the
upper jaw the teeth are limited to the maxillæ, and there
were fourteen to each maxilla. The lower jaw had teeth
along its entire length, and the number given is thirty-
three.
The vertebræ are saddle-shaped. The number of cervical
vertebræ is seventeen. The entire vertebral column con-
sisted of forty-nine vertebræ. None are ankylosed, except, of
course, the sacral series, and some at the end of the tail.
Pneumatic openings were not discoverable in any of the
vertebræ. The atlas has not been found. In no vertebra
do the catapophyses seem to have united to form a ventral
canal, a state of affairs which is occasionally met with in
the Struthiones and is characteristic of the Herodiones and
Steganopodes. The fourteenth cervical is extraordinary by
reason of the enormous size of the two catapophyses, which
are approximated and nearly parallel. The following vertebra
has the first median hypapophysis, which is bifid at the free
39+
STRUCTURE AND CLASSIFICATION OF BIRDS
tip; the hypapophyses die away on the fourth dorsal
vertebra.
With regard to the caudal vertebræ, the most remarkable
fact is that while there is no pygostyle there is no rudi-
mentary state of affairs observable ; for the last few vertebræ
have greatly expanded transverse processes, which would not
move independently. MARSH thinks that 'the end of the tail
would move mainly as a whole. This would give great
power, similar to that in the beaver's tail or the flexible blade
of an oar.'
As to the shoulder girdle, the scapula is in the same
straight line, or nearly so, with the coracoid; it belongs, in
fact, to what FÜRBRINGER has termed the 'platycoracoidal’
type, seen also in the Struthiones. But, contrary to what we
find in those birds, there is not a fusion between the cora-
coids and scapula in Hesperornis, and there is, moreover, a
complete pair of clavicles. The cora coid has a strong pro-
coracoidal process, and also a supra-coracoidal foramen, as in
various Struthiones.
The two coracoids are widely removed at their articula-
tion with the sternum. The clavicles, though complete,
appear to have joined each other ventrally by a joint; they
arise from the procoracoid. The sternum, which has articu-
lar surfaces for five ribs, has no keel. It is notched in the
middle line posteriorly, and is wider in front than behind.
The elongated form of the sternum is compared by MARSH
to that of Uria. The ribs have uncinate processes.
The fore limb of Hesperornis appears to have consisted
only of the humerus, as no other bones were discovered, and
as there were no distal facets for articulation with a radius
and ulna.
The pelvis of Hesperornis in its general form resembles
that of Podiceps. The constituent bones are, however,
entirely free distally. The acetabulum is closed by bone, a
state of affairs only seen in the emu and to some extent in
Tinamics.
The ischium has no processes tending upwards to the
ilium and downwards to the pubis, as in Struthiones.
.
12
.
HESPERORNITHES
395
The prepubic process is large, but not larger than in certain
recent birds, and not so large as in Geococcyx and Tinamus.
The femur of Hesperornis is remarkably short and stout,
more so than in any known bird, recent or fossil. The tibia
has an enormous cnemial crest, as in divers, and the patella
is a huge bone; the latter is perforated by a foramen for the
ambiens muscle. The feet have four toes.
Nothing is known about the soft parts of this bird, save
the feathers, which have been latelyl stated to be quite
ostrich-like. But casts of the brain have brought to light
the interesting fact that it has smaller cerebral hemispheres
than are found in any existing bird.
It seems clear that, as D'ARCY THOMPSON and others have
argued, the nearest affinities of Hesperornis are with the
Colymbi. That they are more nearly related to the ratites
was the opinion of MARSH. The likeness to the ratites,
however, seems mainly to be based upon the degenerate
structure of the wings in both. The degeneration of the
wings, however, has not proceeded along precisely similar
lines. Although the angle between the scapula and the
coracoid is nearly as open as in the ratites, the two bones
have not become ankylosed ; and moreover the clavicles are
retained. The fact that of the fore limb only the humerus
remains (at least in an ossified condition) may be compared
with the fact that in the Dinornithidæ traces of the same
bone have been met with. On the other hand there are
more positive likenesses to the Colymbi, which are not so
clearly due to the immediate action of environment. The
long and narrow pelvis, and the huge cnemial crest with the
relatively enormous patella, are among the more salient points
of resemblance.
The characters in which the Hesperornithes approach the
Colymbi are divided between the two families of the latter
group; in some points Hesperornis is more of a diver ; in
others it comes nearer to the grebes. The following table
of comparison may help to make its mixed' characters
clear :-
In a letter to Nature, April 8, 1897, by Prof. MARSH.
396
STRUCTURE AND CLASSIFICATION OF BIRDS
·
--
-
--
-
-
-
-
-
-
-
-
--
-.
.
-
- -
. -
-
-
-
-
-
.
-
.-
-
-
-
-
--
Hesperornis
Divers
Grebes
-.
Cerv. vert.
Catapoph. canal .
| Hoeincip. . .
· Dors. vert. fused .
Patella . .
Supra-orbit. groores
17
14, 15 i 17-21
0
With expanded With expanded Not so expanded
at ends
None
None
Several
Large
Very small
Large
Large Not marked
ends
ends
-
-
- -
.
.
-
-
-.
.
-
.-
-
.
-
--
.
..
With the grebes Hesperornis agrees in only two of the
characters, and in the remaining four with the divers. It
presents in fact, as might be expected of so ancient a form, a
compound of the grebe and the diver.
We cannot however, in my opinion, put it down defi-
nitely as the ancestral form whence both divers and grebes
have branched off; but it seems to approach that form,
agreeing as it does in most points with the more generalised
divers.
SPHENISCI 2
Definition.—Moderately sized to large birds, with wings' modified to
form a swimming paddle. Aftershaft present. Feathering
continuous. Oil gland tufted. Muscle formula of leg, ABX +.
No biceps brachii or expansor secundariorum. Two carotids.
Skull schizognathous, holorhinal, without basipterygoid pro-
cesses. Dorsal vertebræ markedly opisthocoelous. Scapula
flattened and expanded. Metatarsals short and incompletely
fused.
The anatomy of the penguins has been mainly investi-
gated by MENZBIER ? and WATSON.2 The group, which is
entirely antarctic, contains the genera Eudyptes, Aptenodytes,
Pygosceles, and Spheniscus.
For discussion of the affinities of the Hesperornis gee, besides MARSH and
FÜRBRINGER and Gadow in their large works, FÖRBRINGER, · Über die syste-
matische Stellung der Hesperornithidæ,' Orn. Monatsschr. d. deutsch. Ver. 2.
Schutz. Vögel, xv. 1890, p. 488; F. HELM, 'On the Affinities of Hesperornis,'
Nature, xliii. 1891, p. 368; SHUFELDT, 'On the Affinities of Hesperornis,' ibid.
p. 176; D’A. W. THOMPSON, 'On the Systematic Position of Hesperornis,' Stud.
Mus. Univ. Coll. Dundee, i. 1890.
| 2 Since WATSON'S "Report on the Penguins collected by the Challenger?
the following papers have appeared : M. MENZBIER, Vergleichende Osteologie
der Penguine,' &c., Bull. Soc. Imp. Nat. Mosc., 1887; H. SCHAUINSLAND, ' Zur
Entwickelung des Pinguins,' Verh. Ges. Deutsch. Naturf. Leipzig, 1891, p. 135 ;
STUDER in Zoology of S. M. S. 'Gazellc.'
SPHENISCE
397
The penguins have a continuous feathering, the feathers
acquiring upon the paddle-like wing a scaly aspect;' they
have an aftershaft. The oil gland is tufted.
In the myology of the fore limb the most remarkable
fact is the entire absence of the biceps, a muscle which is
wanting nowhere else among birds. There are also absent
the expanşor secundariorum, scapulo-humeralis anterior, and
serratus metapatagialis. The tensor patagii longus is pre-
sent, and its tendon is inserted on to the whole length of the
bones of the arm as far as the extremity of the last phalanx.
The latissimus dorsi is peculiar in that its two parts, ending
in thin tendons, pass side by side through a pulley arising
from the scapula. The pectoralis major (of E: chrysocome)
meets its fellow in the middle line over the carina sterni, as
in tinamous, &c. In the hind limb the muscle formula is
ABX+. The semimembranosus is remarkable for the fact
that it has, besides the usual head of origin, a second from
the aponeurosis of the abdominal muscles. The accessory
femorocaudal (in E. chrysocome) sends a muscular slip to the
tendon of the femorocaudal. The tibialis anticus divides in
Spheniscus mendiculus into two heads of insertion; in other
species its insertion, as is usual with birds, is single. There
is but one peroneus present, the longus. The deep flexors
are as in birds with but three well-developed toes, i.e. they
blend. In S. demersus there is a slip to the hallux ; in
Pygosceles papua, as in Heliornis, the flexor hallucis splits
into three tendons, one for each branch of flexor profundus,
there being no slip to hallux. The glutæus maximus is
absent in Eudyptes, limited in extent in the other genera.
The ambiens grooves the patella.
In the vascular system the most remarkable fact is the
breaking up of the brachial artery into a rete in the arm.
There are two carotids, which do not fuse. In the leg the
sciatic artery is practically absent.
2212
Ao
? It is stated that when moulting the scale-like feathers of the wing are
detached in a continuous piece, as with reptiles (BARTLETT, P 2. S. 1879,
p. 6).
348
STRUCTURE AND CLASSIFICATION OF BIRDS
11
The tongue and the roof of the mouth are covered with
papillæ.
The proventriculus has a patch of glands upon the right
side, heart-shaped in Eudyptes chrysocome and Spheniscus
demersus ; the gizzard is small and not gizzard-like. In
Pygosceles the proventricular gland, however, is zonary, and
the same state of affairs was found in one of four examples
of Aptenodytes. .
In Eudyptes chrysocome the gut is thrown into a vast
number of primitive irregular folds. The duodenal loop is
excessively complicated, more so than in Haliaetus, to which
it bears some (probably a convergent) resemblance.
The following are the intestinal measurements of a series
of species :-
-
-
-
--
-
-
-
--

Small Iut.
Large Int.
Cæca
-
-
Inches
Eudyptes chrysocome
.
Inches
1}
-
Ft. In.
11 8 (14 ft.,8 in.,
23 ft.)
21 3 (20 ft.)
30 6 (19 ft.)
21 8 (17 ft. 10 in.)
37 (3 in.)
31
.
-
, chrysolophus .
Spheniscus magellanicus
! Aptenodytes longirostris .
-
home
-
A
-
From these data, which are extracted from WATSON'S
memoir already referred to, it is clear that there is some
individual variation in the length of the small intestine
among the penguins, which is indeed, greater than anything
that has been recorded in any other group of birds. That
the cæca are so small is a curious fact in the structure of a
fish-eating bird.
In the liver the right lobe is larger than the left in all
species. The gall bladder is large and extends a long way
down the abdominal cavity, as in the toucans.
The syrinx is not especially divergent in structure. The
trachea has a septum down the middle, as in certain
petrels (9.v.) The intrinsic muscles are attached to the
tracheal rings a considerable distance above the bifurcation
of the tube, the distance varying from species to species.
There is but little fusion between the last rings of the
trachea. In Eudyptes chrysocome there is a thick fibrous
SPHENISCI
399
pad at the commencement of the membrana tympaniformis.
There is a tendency, as in the petrels, to the formation of a
bronchial syrinx. This is especially well seen in Aptenodytes
and Pygosceles. In the latter penguin the rings, three or
four of them, after the bifurcation preserve the character of
the tracheal rings, being deeper than those which follow,
and being at the same time complete rings.
In the penguin's skull the sutures are not so completely
closed as in most birds ; in this they resemble the ratites
among existing birds.
In Eudyptes chrysocome, which may be taken as a type
of the Sphenisci, the skull is schizognathous; the maxillo-
palatines are thin plates which are curved backwards, as in
many Passeres and in some other schizognathous birds; but,
instead of being flatter upon the ventral and dorsal surfaces,
they are compressed laterally. These bones gently nip the
vomer, which is also composed of two flattened rami partially
separated up to nearly the very anterior end. The palatines
are large and flat with a very slightly developed internal
lamina ; they nearly come into contact in the middle line.
The pterygoids are unique among birds for their relatively
immense size; their shape is almost that of the human
scapula, the wider region being at their junction with the
palatines. Each pterygoid is perforated at the middle of
the wider part. The nostrils are holorhinal, and the nasal
bones at their posterior extremity are seen to overlap the
frontals. There are strongly marked impressions for the
supra-orbital glands. The lacrymals reach the jugals, where
they expand into a flattened foot; the descending limb of
each lacrymal, which is flattened out in a plane parallel with
the long axis of the skull, is there perforated by a very large
foramen. It is extraordinary that in this bone, as in the
maxilio-palatines, the plane of the bone is in a different
direction from that of the same bones in other birds. There
are no ossified ectethmoids. On either side of the foramen
magnum are occipital fontanelles of small size. The inter-
orbital septum is largely vacuolate posteriorly. In front of
the occipital condyle, in the region occupied by the basi-
400
STRUCTURE AND CLASSIFICATION OF BIRDS
LIV
U
occipital and the basitemporals, is a hollowed area which
suggests the impress of the potter's thumb. The thumb of
the writer exactly fills it.
The symphysis of the lower jaws is of unusually limited
extent.
The vertebral column of Spheniscus Humboldti consists
of twenty-one vertebræ in front of the sacrum, of which
fifteen are cervical. The atlas is notched for the odontoid
process. The catapophyses do not form a canal; hypapo-
physes commence on the eleventh cervical and continue to
the last dorsal but one; they are large on the twelfth and
thirteenth ; on the fourteenth they have greatly diminished,
but there are two large lateral catapophyses which on C15
form two large flanges (as in the diver) ; these arise from
one base or Di, and gradually diminish into a single median
hypapophysis again. The first dorsal is the first vertebra
to be opisthocoelous, but it is heterocælous in front. The
opisthocoelous characters of the dorsal vertebræ of the
penguins are better marked than in other recent birds in
which the same structure of vertebra occurs (cf. p. 111).
In Edicnemus, for example, some of the dorsal vertebræ are
opisthocælous, but the convexity in front is by no means so
clear as in the penguins.
The scapula is remarkable for its great breadth posteriorly,
which narrows towards the neck. In Pygosceles it is wider
actually as well as relatively than in Spheniscus, and has a
truncated extremity ; the same is the case with Eudyptes
and Aptenodytes.
· The coracoid also shows some differences. In Spheniscus
the procoracoid fuses below with the coracoid, leaving an
oval foramen about half an inch long; at the sternal end of
the bone is a short upwardly directed snag of bone. In
Pygosceles the procoracoid is not fused with the coracoid,
but it is carried on by ligament to the snag at the base of
the coracoid—as probably also in Spheniscus. The acro-
| MENZBIER describes the quadrate as single-headed. This is not accepted
by FÜRBRINGER.
. SPHENISCI
401
LCU
coracoid in both is very long. The furcula is strong and
U-shaped.
The bones of the anterior extremity are extraordinarily
flattened, in accordance with the paddle-like function of the
limb.
The sternum is roughly triangular, with a well-developed
keel. There are two lateral notches (one on each side),
which are united distally by cartilage and membrane. There
is a spina externa, but no spina interna.
The pelvis, unlike what is found in the majority of birds,
is remarkable for the fact that the pubes take a share in the
formation of the acetabulum. The ilia are well separated
from each other by the neural spines of the dorsal vertebræ.
The pelvis is thus perfectly free from, not ankylosed to, the
vertebral column.
The point of chief interest in the hind limb of this group
is the imperfect fusion between the short metatarsals, which
closely resemble those of the dinosaur Ceratosaurus. The
only recent bird which approaches the penguins in the
shortness of these bones is Fregata.
Fossil penguins are the genera Palæeudyptes and Pala-
spheniscus. The latter, from the Tertiaries of New Zealand,
was originally described by HUXLEY,' and later by HECTOR.2
It was a large bird standing some five feet in height, the
were proportionately longer than in recent birds, while the
partly separate metatarsals were as is the case now; hence
this latter character is obviously an inherited one in the
recent penguins.
The affinities of the penguins are not clear. This is due
to their antiquity, the existing characters of the group having
been apparently acquired in the Tertiary period. The main
facts of structure in which the penguins differ from other
birds are-
(1) Continuous feathering (except Chauna).
1. On a Fossil Bird . . . from New Zealand, Q. J. Geol. Soc. 1859, p. 670
p. 341. 'Further Notice of Bones of a Fossil Penguin,' &c., ibid. 1872, p. 438.
D D
402
STRUCTURE AND CLASSIFICATION OF BIRDS
VC
(2) Scale-like feathering of the flattened wing.
(3) Absence of biceps brachii muscle.
(4) Presence of a vascular rete in the wing.
(5) Freedom of cranial bones (not so marked in Ratita).
(7) Large and flattened scapula.
(8) Short and imperfectly fused metatarsals.
The opisthocoelous character of the lumbar vertebræ is
more pronounced than in other birds, but is, as has been
already said, a character found in many groups.
These features, some of them, have appeared so important
to MENZBIER that he has divided birds into four great
groups-Saururæ, Ratitæ, Odontormæ, Carinatæ, and, finally,
the Eupodornithes or penguins. This, however, seems to be
a too great separation from other birds. GADOW would
place them nearest to the Tubinares and Steganopodes, the
Colymbi being only a little further removed.
STEGANOPODES
Definition.- All four toes webbed. Oil gland tufted; aquincubital.
Skull desmognathous, holorhinal, without basipterygoid pro-
cesses.? Cæca present, but small.
YA.
Though this group shows much divergency of structure,
its naturalness can hardly be doubted. The number of
rectrices varies. In Phalacrocorax brasiliensis and graculus
there are twelve, so also in Fregata aquila and Plotus
anhinga.3 Phaeton has twelve or sixteen. P. carbo has four-
teen. Pelecanus has up to twenty and twenty-four.
The aftershaft is minute but distinct in Fregata, appa-
rently absent in Plotus and other genera.
The skin is only slightly pneumatic in Fregata, not so at
all in Plotus. It is distinctly emphysematous in Phaeton,
Pelecanus.
1 This one feature is sufficient to define the group.
? Rudiments exist in Pelecanus ; cf. infra, p. 409.
3 P. melanogaster appears to have only ten.
4 Some few details of the structure of the soft parts of this tern-like
steganopod are to be found in BRANDT, ' Monographia Phaethontum,' Mem. Ac
· STEGANOPODES
403
The tufted oil gland has four orifices in Phalacrocorax
brasiliensis and in Plotus melanogaster. Phaeton has six,
the other genera apparently two, save Pelecanus, which has
the unusually large number of twelve.
The pterylosis, on the other hand, is very uniform, and
the feathering is very close. The neck and head are closely
feathered, and there is a very narrow apterion on the breast.
The spinal tract has a very limited apterion between the
shoulder blades.
The tongue is small in this group, practically obsolete in
Plotus (see fig. 5, p. 20). The proventricular glands are in two
large squarish patches in Phalacrocorax (brasiliensis). The
remarkable modifications of these organs in Plotus are
described later (p. 414.)
The gizzard is very small in Pelecanus and Sula, the
proventriculus being enormous. The glands are zonary in
arrangement.
The following are measurements of the alimentary tract
in a series of Steganopodes. The most remarkable fact to be
noted in the table is the great length of the large intestine
in Plotus.

Small
Intestine
Large
Intestine
Cæca
Inches
Inches
•25
·
Inches
36
42:75
111
·
2
·
m
·
Fregata aquila
Phalacrocorax brasiliensis
carbo
Sula bassana . .
Pelecanus onocrotalus
nitratus.
u rufescens.
Plotus anhinga
57
93
·
#avodno
·
25
1.75
1.25
1.25
(One cæcum
only in some
specimens)
·
·
24
2
·
» Levaillanti .
... melanogaster.
Phaeton sp. . .
30
5.5
2 *
·
*
42
.75
-
-
--
--
-
--
* These measurements are derived from descriptions.
The varying proportions of the liver lobes 1 are given in
St. Petersburg, 1840, p. 239 and pl. v., and in a paper by myself, P. Z. S
1897, p. 288.
"G. ALIX, “Sur l'Anatomie du Pélican,' Bull. Soc. Zool. Fr. ii. 1877, p.
DD 2
404
STRUCTURE AND CLASSIFICATION OF BIRDS
the table on p. 415. The gall bladder appears to be always
present.
The tensores patagii of Fregatal are somewhat compli-
cated. The tensor muscle gives off two tendons, of which
the anterior, the longus, is much the thickest. The latter
is reinforced by an elastic slip from the deltoid ridge of the
humerus, whereupon it again divides into two, a branch
going to fuse with the brevis ; where this branch joins the
brevis tendon that tendon gives off a wristward slip, and is
itself continued over on to the ulnar side of the fore arm.
There is a patagial fan and a bony nodule where it arises
from the junction of the wristward slip of the brevis and the
extensor metacarpi radialis.
In Sula bassana the tendons of the brevis are two from
the very first; the anterior one corresponds to the wristward
slip of Fregata, and from it springs the patagial fan.
The other genera are not very different, save that in none
is there an osseous nodule, and that all have a patagial fan.
The pectoralis I. is double in Fregata, Plotus, Pelecanus,
and Sula, variable in Phaeton, single in Phalacrocorax.
The biceps slip has been occasionally overlooked. It is
present in Plotus, Phalacrocorax,2 Phaeton, and Sula. It is
absent in Pelecanus, Fregata.
Where present, however, it is slender, and is attached
sometimes to the tensor longus, as ordinarily, and sometimes
to the patagium itself, as in Colymbus, Podica, &c. The
deltoid has the scapular slip in Phalacrocorax.
The expansor secundariorum has been commonly said to
be absent from the wing of the steganopods. This is not,
however, at least according to FÜRBRINGER, an accurate
statement of the case. In an embryo of Phalacrocorax
carbo unmistakable traces of it were discovered, while in
287; G. L. DUVERNOY, 'Sur la Poche Mandibulaire du Pélican,' Mer. l’Inst. iii.
1835, p. 219.
| The anatomy of this genus has been described by Burton in Linn. Trans.
vol. xiii. p. 1.
2 Not always. FORBES records its absence in P. brasiliensis. I did not find
one in P. africanus.
3 Not always; it is absent in S. fusca (fide GARROD).
STEGANOPODES
405
Sula and Pelecanus a slender tendon, running from the arm-
pit and ending in unstriated (Sula) or striated (Pelecanus)
fibres for the movement of the secondary feathers, was dis-
covered.
The Viceps is two-headed in the Steganopodes ; but the
arrangement differs from what is common among birds:
Both heads, in fact, arise from the coracoid, but the outer
one, which corresponds to the humeral head of other birds, is
also attached to the humerus. The two muscular bellies are
separate in Pelecanus and Fregata, and their tendons unite
COR.


ISI
- COR.
VA
N
N IH Iliria07do Tri Tiina
S
.
S
MOE
.
V
Fig. 190.- ORIGIN OF BICEPS IN Pelecanus (LEFT-HAND
FIGURE) AND Phalacrocorax (ATTER FÜRBRINGER).
Cor, coracoid ; C, coracoidal head of biceps ; A, attachment of humeral head;
B, its prolongation to coracoid.
to divide again directly. In Fregata, indeed, the division of
the tendon of the coracoidal head takes place before the
junction. In Phalacrocorax africanus I found the coracoid
head alone, and it had but one insertion. In Phaeton and
Phalacrocorax and Sula the tendons of origin of the two
heads from the coracoid are continuous. In Phalacrocorax
and Plotus, at any rate, the anconcus has a humeral head.
The muscles of the leg vary greatly among the Stegano-
podes. The following are the formulæ for the different
genera :—
Phaeton AXY-1 Pelecanus AX -
| ABX + 2
Plotus AX +
Sula AX +
Fregata A+.
Phalaci*ocoran
AX +
Perhaps the ambiens varies. GARROD, FORBES, and I did not find it.
FÜRBRINGER marks it as present, as does GADOW.
2 ABX P. carbo? AX P. lugubris, P. Brasiliensis.
1.
406
STRUCTURE AND CLASSIFICATION OF BIRDS
1
As regards the other leg muscles Phaeton has quite excep-
tionally no tendinous loop for the biceps to pass through.
The plantar tendons blend in Fregata, &c., sending slips
to all four toes; they blend in Phaeton, but send no branch
to hallux. In Plotus there is no blending, but a strong
vinculum, which is attached to flexor perforatus, just as it
splits up into its three branches. This too is the case with
Phalacrocorax, but the vinculum is not strong.
In the pelicans (at any rate in P. rufescens and P.
mitratus) there is a curious relationship between the femoro-
caudal and the semitendinosus. The former receives a tendi-
nous slip not far from its insertion, which runs up from the
middle of the semitendinosus at right angles to its fibres.
Whether this may be regarded as a rudiment of the accessory
semitendinosus or not is uncertain.
. Another peculiarity shared with Biziura lobata, Colymbus,
and the extinct Hesperornis is the perforating of the patella
by the tendon of the ambiens in Phalacrocorax. In Plotus
there is a groove upon the ossified patella, and, remarks
Professor GARROD, “ some of the fibrous ligament overlapping
this groove shows traces of ossification; so that in aged birds
this groove may be converted into a foramen.'
Glutæus I. in the Steganopodes is a small muscle, not
extending, or hardly extending, over the biceps. Glutaus
V. is large. In Fregata glutæus I. is absent.
The form of the syrinx of the Steganopodes varies con-
siderably, but in all it is tracheo-bronchial ; intrinsic muscles
may be present or absent.2
Of Pelecanus I have examined six species, viz. P. mitratus,
P. onocrotalus, P. rufescens, P. fuscus, P. conspicillatus, and
P. crispus. In none are there any intrinsic muscles, and the
bronchidesmus appears to be complete.
In P. conspicillatus the organ of voice is very simple.
The rings are but little modified. There is a bony pessulus,
which is attached behind to the last two tracheal rings,
| This peculiarity is, however, to be found in the swifts.
? The anatomy of Pelecanus rufescens has been described by OWEN, P. Z. S.
1835, p. 9, by MARTIN, ibid. p. 16, and by Alix, loc. cit. on p. 403, above.
STEGANOPODES
407
which are fused and ossified where they pass into it; in
front the last of these and the next following are ossified and
fused in the middle line; the middle one of the three is con-
tinuous with the pessulus.
P.mitratus chiefly differs in the larger number of rings with
which the broad three-way piece comes into contact in front
and in the greater length of the membrana tympaniformis.
P. fuscus is remarkable for the degree in which the
syrinx is flattened from before backwards. This is caused
by the straightening of two of the bronchial semi-rings,
which thus come, though hardly longer than the others, to
project out considerably beyond them. At a first glance
these two semi-rings appear to be the first two of the bron-
chial series which are commonly among birds different from
those which follow. There are, however, five pairs of bars
in front of them, only separated in the middle line in front
by a furrow; on slitting up the windpipe it may be observed
that there is really a septum between them, and that they
are bronchial. Owing to the peculiar form of the sixth and
seventh semi-rings the membrana tympaniformis is exposed
behind, but not in front.
P. onocrotalus and P. crispus have syringes which are
very much alike. When removed from the body, at any
rate, the bronchi stand out at right angles to the trachea.
This is due to the very large posterior end of the pessulus,
which is broadened into a bar at right angles to and longer
than the median portion of the pessulus. It is not ossified.
There is a slight dilatation of each bronchus, which is carried
to an excess in the next species.
In P. rufescens the characters of the syrinx of the last
species are carried to an extreme. The pessulus is the same
in shape, but ossified. The bronchi are greatly swollen for
the space of about an inch, there being occasionally some
forking and anastomosing of the individual rings. The ends
of the rings in the swollen region are nearly in contact, being
separated only by a narrow membranous interval.
In Fregata aquila the syrinx has a pair of intrinsic
muscles and the bronchidesmus is incomplete. The syrinx
YA
UUUU
408
STRUCTURE AND CLASSIFICATION OF BIRDS
LOT 1
is flattened from before backwards, and the first two bronchial
semi-rings are very prominent. To the first of them, and
apparently also to the ring in front, are attached the two
muscles into which the intrinsic muscle divides. There is
a membranous gap separating the last of the, specialised
bronchial semi-rings from the first of those which follow,
whose border, moreover, is concave upwards. The last few
tracheal rings are ossified and firmly fused.
Phalacrocorax has a complete bronchidesmus and a single
pair of intrinsic muscles. The first three bronchial semi-
rings are very prominent and arched, and to the third of
these the intrinsic muscles are attached. There is a mem-
branous gap between the last of these and the first of the
remaining series of bronchial semi-rings, which forms, at any
rate in P. carbo, quite a pocket. The fourth bronchial semi-
. ring is curved in the same direction as that which precedes
it; both, in fact, are convex. The curvature, which is slightly
more marked in P. brasiliensis than in either P. carbo or
P. varius, suggests very much the syrinx of certain auks
(cf. p. 363). In P. varius the intrinsic muscles are attached
to the second bronchial semi-ring, as also in P. brasiliensis.
The syrinx of Plotus does not differ greatly, but it has an
incomplete bronchidesmus. There are two bronchial semi-
rings, which are specially increased in length and depth ;
they are the second and third, and are relatively stouter than
those of Phalacrocorax; to the first of them the intrinsic
muscles are attached.
The syrinx of Sula is a good deal different from that of
other steganopods.
There is no ossification, except in the pessulus. A square
projection is formed by a fusion between last tracheal rings;
this is continuous with the pessulus and is well shown in
GARROD's figure. The bronchial semi-rings are at first
feeble with wide interval. Between the third and fourth of
them there is, covering the insertion of the intrinsic muscle,
a protuberant pad of elastic tissue about the size and shape
of a pea,
P. Z. S. 1876, pl. xxxviii. fig. 4.
.
STEGANOPODES
409
In Phaeton flavirostris the syrinx is typically tracheo-
bronchial and not flattened, as in Fregata.
The skull of the Steganopodes 1 is desmognathous. It is
most extremely so in Pelecanus, in correlation, perhaps, with
the long broad beak. Pelecanus, in fact, may be described
as doubly desmognathous, for the palatines are not merely
united but ankylosed behind the posterior nares, which are
of limited extent. They form but one bone with a deep
ventral median crest, and on the opposite side an equally
pronounced dorsal crest, occupying a space left by the here
deficient interorbital septum. Fregata is nearly at the
other extreme, for the maxillo-palatines are largely free from
each other in the middle line, and the palatines are only
united for a short distance posteriorly. Phaeton ? is most
like Fregata, but here there is no fusion between the
palatines. The strong inferior crest of Pelecanus is repre-
sented by two feeble ridges of limited extent. Phalacrocorax
is intermediate. The maxillo-palatines are completely united.
The palatines are fused for the greater part of their length
posteriorly; they are, however, quite flat above and have below
but a faint trace of the median crest. The interpalatine
space anteriorly is much more capacious than in Pelecanus.
Plotus agrees with Phalacrocorax.
The Steganopodes are generally (HUXLEY, FÜRBRINGER,
GADOW) said to have no basipterygoid processes. In
Pelecanus rufescens, however, I find a pair of thorn-like
outgrowths in the right position (cf. Platalea, p. 439), which
I take to be the rudiments of these structures.
The bony nostrils are holorhinal, pervious only in Phaeton,
in others much obliterated by bony growths, as in Herodiones ;
in Plotus, indeed, reduced to the merest chinks. As in some
Herodiones and Tubinares they are continued forward by a
marked groove which runs to, or near to, the very end of
the bill, absent only in Phaeton. In Fregata there is no
| All the types are described and figured by BRANDT, ' Zur Osteologie der
Vögel, Men. Aki St. Petersb. 1840 (6), iii. p. 81. See also for osteology of
Plotus and Phaeton MILNE-EDWARDS in Hist. Nat. Madagascar.
2 BEDDARD, ' Notes upon the Anatomy of Phaeton,' P. 2. S. 1897, p. 288.
410
STRUCTURE AND CLASSIFICATION OF BIRDS

NOTA
-
RAR
-
1
SRL
CU
BER
SIA
--
ES
I
ZA
.EE
.
AL
W
S
hinge line separating the
cranium from the face.
This is present in Pele-
canus and Phaeton, while
in Phalacrocorax and
Plotus the existence of
fibro-cartilage allows of a
free motion.
The lacrymal in Fre-
gata and Pelecanus is large,
with a large descending
process, which in both
reaches the jugal bar; in
addition Fregata has an
uncinate bone, which
reaches the palatine. Of
this there is apparently a
rudiment in Phaeton.
In Phalacrocorax the
descending process of the
lacrymal completely blends
Mxp.
with the ectethmoid to
form a ring of bone, as in
the Limicolæ. In Plotus
the same thing occurs, but
the lacrymal is much
smaller. The interorbital
septum as an ossified
structure is almost com-
plete in Pelecanus and
Fregata, largely deficient
in Phaeton, almost absent
in Phalacrocorax and
Plotus. In Phalacrocora:X
carbo there is a small
bonelet resting upon the
REN
jugal bar in front of the
Fig. 191.— SKULL or Fregata. VENTRAL incromolil this
I lacrymal ;l this
is also
ASPECT. (AFTER BEDDARD.)
is also
Vo, vomer ; Mæp, maxillo-palatines ; %, upwardly Ossicului supraijugale of BRANDT.
IL
64
.
.
.
.
.
.
2
AL
.
LET
.
nr.
Z
1
+
.
.
1
+
.
.
aan
W
'
IT
HRIN
OA
11
DEN
directed part of maxillo-palatines.
STEGANOPODES
411
Tuo
.
.....
.
well developed in Plotus. There are traces of it in Fregata.
Another peculiarity shared by Phalacrocorax and Plotus is
a style-like bone l attached to the occipital, to which the
temporal muscles are partly attached. The bone varies in
size, is not ankylosed to the skull, and is probably to be
looked upon as an ossification in the septum between the
two muscles. In these birds also
the quadrate is peculiar in form in
that the anterior process is short
and slender and at right angles to
the rest of the bone.
Sula is nearest to Phalacroco-
Yax. It has the same peculiar
form of the quadrate bone, and
the equivalent of the small bone
seated upon the jugal bone is Mop:--
apparently there, though anky-
losed. The nostrils too are re-
duced to a mere pinhole, as in
Plotus. The palatines agree ab-
solutely with those of Phalacro-
Corax and Plotus, but the interor-
bital septum is not so completely
vacuolate. It rises up, more-
over, in front, as in Pelecanus,
and a faint crest from the pala-
tines ascends into the vacuity. FIG. 192.—SEULL OF Phaeton
The
The lacrymal is,
Loormal is however
however, (AF"
(AFTER BEDDARD). LETTERING
AS IN FIG. 191.
different; the orbital part is
small, but the descending bar is large and joins the jugal ;
the ectethmoids appear to be deficient as bony structures.

SCAN
*
M
--
17
-
-
XIVA
E.
.
T!
.
1
CCM
Muir
4.
lide
.
WD
All
1
| J. A. JEFFRIES, · The Osteology of the Cormorant,' Science, ii. p. 739, iii.
pp. 59, 274 ; GILL, ' Osteology of the Cormorant, ibid. iii. p. 404 ; SHUFELDT,
Remarks upon the Osteology of Ph. bicristatus,' ibid. ii. p. 640, and · Osteology
of the Cormorant,' ibid. iii. p. 143; DOLLO, Bull. Mus. Roy. Belg. iii. 1884, p.
130. This bone (xiphoid, YARRELL; nuchal, MARSH ; intranuchal, DOLLO) has
been wrongly compared with the post-occipitals of dinosaurs. It is merely a
sesamoid. LUCAS, “Description of some Bones of Pallas's Cormorant (Ph.
perspicillatus), P. U. S. Nat. Mus. xii. 1889, p. 88.
412
STRUCTURE AND CLASSIFICATION OF BIRDS
1
C
The lacrymal, as in Pelecanus and Fregata, is deeply notched
laterally.
MIVART, from his investigations into the axial skeleton
of this group,1 set aside Phaeton and Fregata by reason of
their possessing twelve or thirteen cervical vertebræ and
the doubly notched (on each side) sternum of Phaeton,
besides a number of other points.
There are seventeen cervical vertebrce in Pelecanus,
eighteen in Sula, twenty in Phalacrocorax.
The atlas vertebra is notched for the reception of the
odontoid process in Pelecanus, perforated in Sula and Plotus ;
in Phalacrocorax the conditions are intermediate, a perfora-
tion being only just closed above.
The Steganopodes have catapophyses upon some of the
cervical vertebræ which enclose a canal; in Pelecanus this
is found on vertebræ 8-15. In Sula, the canal may com-
mence on the same vertebra, but more usually on the ninth,
extending to the thirteenth. In Phalacrocorax there are no
vertebræ with a complete hæmal arch formed by union of
the catapophyses. In Plotus the canal begins on the ninth
vertebra and extends to the fourteenth. In Phaeton there is
no canal. The dorsal vertebræ are opisthocoelous in Phala-
Cl'ocorax and Plotus, not in Sula and Pelecanus.
In all these genera the sternum is at niost only slightly
notched by one notch only on each side. In Pelecanus the
clavicles are ankylosed to its keel. They reach it in Plotus,
Phalacrocorax, and Sula, but are only firmly connected by
ligaments, not ankylosed. In Phaeton the clavicles are
attached to the keel behind the extremity.
Both spina externa and interna are wanting in Sula and
Pelecanus ; the spina externa is present, but small, in Phala-
Crocorax; contrary to the statement of FÜRBRINGER (in
his tables) I find a rudimentary spina externa in Plotus
anhinga. Fregata and Phaeton show their divergence from
the normal steganopod type by a better developed spina
externa, while the latter bird may possess a rudimentary spina
interna. Four to six ribs reach the sternum.
1.On the Axial Skeleton of the Pelecanidæ,' Tr. 2. S. x. p. 315.
021
STEGANOPODES
413
· The relationship of the clavicles to the scapula and to the
coracoid, upon which FÜRBRINGER has laid so much stress,
serves to differentiate some of the Steganopodes. In Plotus
the clavicle is connected by ligament with the scapula; this
connection is nearly effected in Phalacrocorax and Sula, but
not in Pelecanus. In Fregata the dilated end of the clavicle
is perforated in the middle ; it is, moreover, fused with the
scapula.
The genus Plotus (consisting of the four species P. anhinga,
P. melanogaster", P. Nove Hollandiæ, and P. Levaillanti) has been
investigated by BRANDT, EYTON,” DÖNITZ,3 GARROD,4 FORBES,5 FÜR-
BRINGER,S and myself. Many of its characters have been described
in the foregoing pages. I shall here direct attention to certain
peculiarities of P.lotus which it does not share with the other
Steganopodes, or which it possesses in a more marked degree than
its nearest ally, Phalacrocorax. The darters feed in a peculiar
manner; they pursue fishes under water with a jerky action of the
head and neck. This action, as Mr. FORBES has suggested, may
be compared to that of a man poising a spear before hurling it.
* Arrived within striking distance,' continues Mr. FORBES, 'the
darter suddenly transfixes-in fact, bayonets—the fish on the tip of
its beak with marvellous dexterity, and then immediately comes
to the surface, where the fish is shaken off the beak by jerking of
the head and neck, thrown upwards, and swallowed, usually head
first. This mechanical action is associated with a mechanism in
the neck.
The first eight vertebræ form a continuous curve forwards, so
marked that the head when outstretched is in the same straight
line with the eighth vertebra. This latter vertebra is articulated
at right angles with the foregoing, and almost at right angles with
that which follows; there is thus formed a conspicuous kink in
the neck, which is never unbent.
1 Loc. cit. (on p. 409.)
2 Osteologia Aviun, p. 218.
3. Ueber die Halswirbelsäule der Vögel,' &c., Arch. f. Anat. u. Phys. 1873,
p. 357.
4 "Notes on the Anatomy of Plotus anhinga,' P. Z. S. 1876, p. 335, and
"Note on Points in the Anatomy of Levaillant's Darter (Plotus Levaillanti),' ibid.
1878, p. 679.
5. On some points in the Anatomy of the Indian Darter,' &c., ibid. 1882,
p. 208.
6 Notes on the Anatomy and Osteology of the Indian Darter (Plotus
melanogaster),' ibid. 1892, p. 291.
414
STRUCTURE AND CLASSIFICATION OF BIRDS
On the ninth vertebra there is on the dorsal surface a fibrous
loop (Dönitz's bridge'), which is fibrous only in P. anhinga,
ossified in the three other species. Through this loop passes the
tendon of the longus colli posterior muscle to be inserted on to
vertebræ 2, 3, 4. The longus colli anterior is a very powerful
muscle, which ends in a long tendon attached anteriorly to the

!
2
20
VI
1.
!
.
NSV
Nel
YUX
V.
222
.
WO
.
AS
.
!
JA
WRIT
SPL
LE
TU
.
A
.
M
22
Veluk
mi!
1
>
S
UNI.
R
..
DUTE
11
.
AN
win
VEIS
2::::
1859
:
BE
ES EJUS
24
.
M
is
INA
WS
-
S
***
.
SO
-
AP
.
23
A
YA
KER
>
SIE
.
.
INI
SS
OB
V
VIA
.
OG
-
BUTY
10
WA
H
/1
9
IN
.
SAS
42
C
COL
.
hu
RISAS
US
ID
20
las
SV
ANY
PIX
.
S
11.11
.
.
AU411
SAU
S
_
.
21
22
.
.
.
1
w
II
You
Jo
ES
17
12
AAA
HA
TATUIMMT
IZO
EEE
!!!T7
Fig. 193.--STOMACH OF LEVAILLANT'S DARTER (AFTER GARROD).
hæmapophysis of cervical vertebræ 8–10. A separate portion of
the muscle is similarly attached to the eleventh.
The pulling back of the head preparatory to striking is effected
by the longus colli posterior, while the bayonetting movement
is produced by the longus colli anterior.
The second characteristic feature in the organisation of Plotus
concerns the stomach. Though originally described by MACGILLI-
STEGANOPODES
415
s, constitutietely lined by the well-marked.com of the
ric portion of mpletely lined becal diverti
VRAY in AUDUBON’s ornithological miscellany, it has been more fully
described and illustrated by GARROD and FORBES. One great
peculiarity is that in P.anhinga the proventricular glands, instead
of forming a patch, or patches, upon the inner surface of the
proventriculus, constitute a special cæcal diverticulum of the
stomach, which is completely lined by the glands in question.
The pyloric portion of the stomach forms a well-marked compart-
ment, quite distinct from the gizzard region; the opening of the
pylorus into the duodenum is protected by a dense mat of hair-
like processes, each of which is about half an inch in length.
Microscopically these structures are much more like true hairs'
than like any filiform papillæ which might occur in such places.
In P. Levaillanti there is no special compartment for the pyloric
proventricular glands. The hairs lining the pyloric chamber have
a more complex arrangement than in P. anhinga. There is
(fig. 193) a dense mass of them lining the distal end of the pouch,
but there is also a singular conical process of the mucous mem-
brane, covered with more hairs and serving to close the pylorus.
P. melanogaster agrees with the last species, but the plug is less
developed, being rather a well-defined ridge than a retractile plug.
Mr. FORBES thinks that this hairy plug of the darters is an
exaggeration of the nipple-like valve which is found to guard the
pylorus in many birds. The two Old-World species thus come
nearer together, as they do in the ossification of Dönitz's bridge,
than does either to the New World P. anhinga.
In order to facilitate a comparison of the several genera
of Steganopodes among themselves, the annexed table, indi-
cating the differences in some of the muscles, viscera, and
bones, may be of use :-

Muscle Formula
of Leg
Exp. Sec.
Bic. Slip
Carotids
Liver Lobes
| Lateral Muscles
of Syrinx
Cerv. Vert.
Tomer
Maxillo-
palatines
Fregata
Pelecanus.
Phaeton
At
AX-
AXY
Oto!
too!
1
R2>
R2>L
R>L
15
17
15
Single
Rud.
Double
posteriorly
Free
Fused
Free
tot + + +
20.
O'?
Phalacrocorax .
Plotus
Sula -
AX+
AX+
++
Hlo
o
R2>L
R2>I
R>L
0?
tot
Absent
Abseut
Absent
+
+ or 0 2 or 1
The Steganopodes, though allowed by all to be a natural
416
STRUCTURE AND CLASSIFICATION OF BIRDS
2
TO
group, show, as is indicated in the above table, a considerable
amount of variation among themselves. And, what is even
more striking, the genera vary more than genera as a rule do
-for example, the stomach of the darters, the biceps and
carotid of Sula, and the muscle formula of the leg of Phala-
Crocorax. The accompanying table gives some of the chief
characters of the several genera. It is interesting to observe
from this table that there is to some extent a linear
series to be deduced from the facts of structure. If we
commence with Phalacrocorax, we may associate with it
certainly Plotus and also Sula. In these genera the peculiar
flat and largely fused palatines are associated with the
muscle formula AX+. Sula offers a slight step in the
direction of Pelecanus. There is a trace of the dorsal ridge
of the palatine, and of the anterior vacuity in the interorbital
septum for the reception of this edge. In Pelecanus these
characters are fully realised, and at the same time the
ambiens has vanished. Fregata, which stands apart in the
structure of its skull, is also unique in the group by reason
of its muscle formula, which is only A+. But this genus
and Pelecanus have lost the biceps slip, present in those
referred to before, but commencing to disappear in Sula.
The question is, In what direction has the modification
gone? Are we to start with Phalacrocorax or with Pelecanus,
or with some other genus ?
The answer to this question naturally depends upon the
relationship of the Steganopodes to other groups. The group
to which they are most nearly allied appears to me (as to
FORBES and others) to be the Tubinares. In estimating this
affinity. FORBES did not, in my opinion, lay sufficient stress
upon the 'os uncinatum. It is true that-as he states-
this bone appears also to be present in Chunga and in the
touracos, not to mention other birds; but in Chunga it is a
continuation of the descending process of the lacrymal, and
articulates with the jugal bar, while in Corythaix it articu-
lates both with ectethmoid and lacrymal, though it ends, as
in the birds under consideration, on the palatine. In both
Fregata and Diomedea this bone connects the lacrymal with
STEGANOPODES .
417
11
the palatine, the lacrymal itself reaching (or nearly so) the
jugal bar. The palate of Diomedea is remarkably like that of
Fregata, which, unlike other Steganopodes (except Phaeton),
is not far from being schizognathous, and represents, I am
disposed to think, the nearest intermediate form. The
grooves, starting from the nostrils and running towards the
end of the beak, are also found in the Tubinares (and in the
Herodiones, with which latter group the Steganopodes share
the very much reduced, and yet holorhinal, nostrils). Another
fact which is perhaps of importance is the much-reduced
gizzard and the correspondingly enlarged proventriculus.
Less important likenesses are the double pectoral, the short
colic cæca, which are occasionally reduced to one in the
Steganopodes; these points ally the group to the Herodiones
as well as to the Tubinares. The very names Fregata and
Fregetta, Pelecanus and Pelecanoides are an expression of
these views.
FÜRBRINGER, however, and GADOW place Phaeton near-
est to the base of the steganopod series, and there is much
to be said for this way of looking at the group. There is no
doubt that Phaeton is very different from the other genera
of the group; indeed, if it were not for Fregata it would be
difficult to avoid removing it altogether. It is really not
desmognathous (in the sense of HUXLEY); for the maxillo-
palatines do not fuse; in front of them there is a bony plat-
form, forming the hard palate, but this is produced from
anterior ingrowths of the maxillæ, not homologous with the
maxillo-palatines, which are present and unfused. The
vomer, moreover, is well developed and bifid' posteriorly,
being exceedingly like the bifid vomer of such schizognathous
birds as the grebe, Æchmophorus. In Fregata we have a
further step. The vomer has coalesced into a single rod;
the palatines have united posteriorly; the os uncinatum,
rudimentary in Phaeton, has increased (?), and the grooves
running from the nostrils to the end of the beak have put in
an appearance ; furthermore the nostrils, pervious in Phae-
ton, have acquired the steganopodous imperviousness. The
maxillo-palatines, however, are not united ; but beneath them
Ε
Ε
418
STRUCTURE AND CLASSIFICATION OF BIRDS
VOU
is a slanting wall of bone (cf. fig. 191 X), present in all the
other Steganopodes, co-existing with and lying below the
maxillo-palatines, and therefore not comparable to them.
True maxillo-palatines, indeed, seem to be only present in
Pelecanus of the remaining genera of the family, where they
are small and coalesced. The other genera have only the up-
wardly sloping bone of Fregata. The vomer too appears to
be at the most very small in the higher steganopods, and
I have not been able to find it. .
All these facts point to the basal position of Phaetori.
It has, however, in the loss of the ambiens departed from
the primitive condition. We can derive Fregata from
Phaeton; but in this case the mutual relations of the
Steganopodes and the Tubinares, and perhaps the Colymbi,
become somewhat obscured.
As perhaps an appendix to the present group we may
consider Odontopteryx toliapicus of the London clay, known?
by a portion of a skull.
FÜRBRINGER discusses this bird very slightly under the
Tubinares and Anseres ; both GADOW and LYDEKKER place it
near the Steganopodes, with which determination I associate
myself. The most marked peculiarity of this bird, which
has given to it its name, is the serration into longer and
.shorter teeth of the upper and lower jaw. The two jaws are
grooved, which seems to indicate that the beak was, as in
the Steganopodes (and other birds for that matter), divided
into several pieces. On the right-hand side of the skull is a
small notch, which has been identified with the bony nostril
of that side. It has, however, in the drawings an accidental
look, and the fact of the possible obliteration of the nostrils
must be weighed in discussing the steganopodous affinities
of the Odontopteryx; for in many of those birds, especially
in Sula and Plotus, the nostrils have been practically oblite-
rated. It does not seem to me that the depressed form of the
skull, or, so far as we can judge them, the shape of the
lacrymals, is strong evidence in favour of the steganopodous
OWEN, ' Description of the Skull of a Dentigerous Bird,' &c., Q. J. Geol.
Soc. 1873, p. 511.
STEGANOPODES
419
CU
relationships of this remarkable fossil; but the facts are at
any rate not opposed to that placing.
Of birds more definitely referred to the Steganopodes a large
number have been described from Tertiary strata. If MARSH'S
Graiculavus, from the Cretaceous, really belongs here, the group is
as old as any existing group, and older than most. Argillornis
(= Lithornis) of Owen is among the most interesting, inasmuch
as it is known from fuller remains than others. The skull and
some long bones have been found in the London clay. It is
referred to the neighbourhood of the present group by LYDEKKER,
but by FÜRBRINGER to the Ichthyornithes.
Actiornis, Pelargornis are placed here by LYDEKKER, and FÜR-
BRINGER would include Remiornis (considered struthious by
GADOW) and Chenornis, referred by others to the Anseres.
HERODIONES
Definition.--Oil gland feathered. Aftershaft present. Aquincubital.
Skull desmognathous, holorhinal, without basipterygoid pro-
cesses. Catapophysial canal nearly always present. Two
carotids. Cæca present, but nearly always rudimentary. Ex-
pansor secundariorum present.
This group of birds is an extensive one, with a con-
siderable range of structural variation. That the flamingoes
form a group apart can hardly be doubted, though it is not
easy to differentiate them by any very important characters
from other Herodiones. Less easy is it to distinguish the
herons from the storks. The extreme types, e.g. Ciconia
and Cancroma, can be readily distinguished by the muscle
formula and by the characters of the syrinx, not to mention
some other points of minor importance; but between the
extremes are forms like Abdimia, Scopus, and Balaniceps,
which forbid so sharp a line of division. As to Phoni-
copterus, WELDON was the first 3 to show in a convincing
way its likenesses to the stork, its previous association with
the duck tribe having been in large part due to the lamellated
bill and the webbed feet. As to the latter character, no one
1 Except in Cancrona.
? ? except in Leptoptilus argala.
3 On some points in the Anatomy of Phonicopterus,' &c., P. Z. S. 1883,
p. 638.
E
2
E
420
STRUCTURE AND CLASSIFICATION OF BIRDS
would nowadays associate the gulls with the ducks for a similar
reason, though it was, of course, done by the earlier ornitho-
logists. The duck-like bill of the flamingo is not so exclusively
anatiform as might be thought; for a very decided stork,
Anastomus, has a bill which has very much the same
structure as regards the lamellæ (hence, indeed, its specific
name-lamelligerus).
The typical storks may be distinguished from the typical
herons by the following table :-
-
---...
anca.---
W
A
-
-
-
-
--
-
-
-
-
-
.
-
-
-.
-
...--
..
-
-
-
-
-
-
-
-
--
-
----
-
--
-
Ciconiida
Ardeilla
--
---
-
.
.---..
Syrinx . . . Without intr. muscles. With intr. muscles.
In Tracheal
Tracheo-bronchial
Creca . . .
2, small
1, small
Powder-couns.
0
Pterylce .
Wide
Narrow
Pectoralis 1.
In two layers
Single
Cucullaris dorsocuta- :
NCILS . .
Pectoralis abd..
Vinculuin of deep flexor
Strong
Weak or absent
tendons
Ambiens
+ or 0
Carotids .
2, separate
2, fused
--
.-.
.-
.
....
--..-
-
-
--
-
- .
The set of differences may be certainly regarded as of
family value. But it must always be remembered that there
are tendencies to the heron-like organisation among true
storks; while Scopus, and possibly Balaniceps, are distinctly
intermediate.
Family Scopidæ.—There is one genus only, containing but
a single species, Scopus umbretta-African and from Mada-
gascar. The anatomy of this stork-like heron has been prin-
cipally investigated, as regards the 'soft parts,' by myself.1
It differs from the true herons by the absence of powder-
down patches, in having ten primaries instead of eleven, and
in possessing sixteen cervical vertebrce. On the other hand
it differs from the storks in having an ardeiform-or at
least a 'typical'-syrinx, and (from the Plataleida) in the
L'A Contribution to the Anatomy of Scopus umbretta, P. Z. S. 1884,
p. 543.
HERODIONES
421
absence of a biceps slip to the patagium. Its leg muscle
formula too is that of a heron. Besides these facts-


Flih-

-F2.P
SU
-
"
WA
HIVI NISUNF
ve
AN
HMISIIN UUTTUR
UKIT
WIDTH
Wh
.
LU
VERENIE
CAS
*
.
/
DIRI
AA
NL
i
AST
JOOML
IV
III
Fig. 194.---SYRINX OF Scopus (AFTER
BEDDARD). (. FRONT VIEW. b. SIDE
VIEW.
Fig. 195.- DEEP PLANTAR TENDONS
or Scopus (AFTER BEDDARD).
Fl.), flexor hallucis: Fl.p, flexor profundus.
which incline to both the stork and the heron side, and
may be mentioned that Scopus shows a stork-like character
in the partial division of the pectoralis primus,
a fact which was first pointed out by FORBES
incidentally, in his report upon the petrels
collected during the voyage of the Chal-
lenger.' The patagial muscles and tendons
are not specially distinctive of the affinities
of the bird. In my dissection of Scopus I
could not find the expansor secundariorum ;
but as this muscle is found in most of the
Herodiones its absence is not in any way sig- Fig. 196. -- Dump
nificant, though it should doubtless be PLANTAR TENDONS
or Scopus (AFTER
verified. The anconcus has a tendinous slip BEDDARD).
to the humerus. The deep plantar tendons
appear to vary somewhat; in two specimens dissected by
inyself I met with the two conditions illustrated in the two

ni
YY 1
422
STRUCTURE AND CLASSIFICATION OF BIRDS
I CU
.
L
Uhr
SULI
ma
www
4
1
figures annexed. In the one the flexor hallucis was united
to the flexor communis by two distinct vincula, one before
the trifurcation of the latter tendon, the other attached to
the tendon supplying digit II. In a specimen of Ciconia
nigra dissected by FORBES there was an identical arrange-
ment. In the other Scopus (see fig. 195) only the last of
the two vincula was present, i.e. that passing to tendon of
digit II.
For the skeleton of Scopus see MILNE-EDWARDS's account.'
The skull is on the whole more
stork-like than heron-like, but it does
not show any of the extreme modifi-
cations of the stork type. The bony
interorbital septum, as in the storks, is
not largely fenestrate. The inner
lamina of the palatines does not reach
the posterior boundary of those bones.
In front, at about the middle of the
interpalatine vacuity, the palatines are
produced into a short lateral process ;
this is well marked in many storks,
but also in Cancroma, to the skull of
which heron that of Scopus shows
ITIG. 197.--SYRINX or another point of likeness; in both
Leptoptilus (AFTER these birds a deepish groove runs from
WELDON).
the end of the nostril to the end of the
bill. This groove is also found, though it is not so con-
spicuous, in Ardea and Butorides, and (among storks only)
in Platalea; it is suggestive of a recently closed, more
elongated nostril, like that of the cranes. The procoracoid
is more rudimentary than in storks, but the coracoids overlap
at insertion.

wer
TUIS
STANE
YA
BO
S
.
.
u
..
JUN
so
WA
.
*4*
Family Ciconiidæ.-I include in this family not only the
true storks but also the wood ibises (Tantalus). GARROD ?
| Histoire Naturelle, c., de Madagascar, 'Oiseaux,' p. 514.
?F. E. BEDDARD), "Notes on the Convoluted Trachea of a Curassow (No-
thucrax urumuturn), and on the Syrinx in certain Storks,' P. 2. S. 1886, p. 321.
HERODIONES
423
contrasted Ibis and Platalea on the one hand with Ciconia
and Tantalus on the other, on account of the following
differences :-
Ibis and Platalea
Ciconia and Tantalus
Skull schizorhinal, angle of man Skull holorhinal, angle of mandible
dible produced.
truncated.
Pectoralis major single.
Pectoralis double.
Accessory femorocaudal present. Accessory femorocaudal absent.
Semitendinosus muscular through- 1 Semitendinosus tendinous for
out.
distal half.
Biceps slip present.
Biceps slip absent.
To which I add the form of the syrinx. These collec-
tively appear tu me to justify this separation. The true

}
ur
Uut

WAS
U111
UR
-
A
Le
BA
Sheikh
06
FACE
9
.
V
AU
t
.
SED
!
Net
NOUA
E-
--
.
*
CS
item
.
.
.
.
N
"
MOODLE
270
.
.
H
1
ANYS
U
nit
Bunt
.
.
un
itu,
tatt
..
MIN
II/
I
SENA
VIII
AUDIO
Recit
FEEEEEEEEEEEEF
...
it.fr
EEEEEga
HUND
VE
UUUU
.
uta
ila
:
.
os
WEZA
E
?
A..
22
FIG. 198.-SYRINX OF Dissura
episcopus (AFTER BEDDARD).
FIG. 199.-SYRINX OF Abdimia sphenn-
rhyncha (AFTER BEDDARD).
storks, including Tantalus, are well characterised by the
peculiar structure of the trachea and syrinx, there being, as
already mentioned, an approach in these birds to the purely
tracheal syrinx of the tracheophone Passeres. In the
common black stork, C. nigra, the syrinx has the form illus-
trated in the figure (fig. 197). Its principal features are the
absence of intrinsic muscles, the modification of the last
tracheal rings, the existence of a rudimentary vocal process
(see p. 69), and the closed character of the bronchial rings,
which are rings, not semi-rings, the membrana tympani-
424
STRUCTURE AND CLASSIFICATION OF BIRDS
formis being absent. In Xenorhynchus senegalensis, how-
ever (fig. 200), there is some approach to the more typical
tracheo-bronchial syrinx, which is further developed in
Abdimia sphenorhyncha and Dissura episcopus;1 the
syringes of these two storks are illustrated herewith (figs. 199,

VI
HR11
:
PRIH
-
W
P
.
ir
VZ.
-
.
.
Molt
.
.
RAUN1111
"
..
RSY
MI
?
H
.
-.-
-
-
-
.
-
.
17
i.
.
dr
.
*,
V-
1
Pt.
SA
.6
.
PE
3
-
TX
SATURO
TO
PT
AL
ESES
Ee
I ASSIST
:
LAS
NN
-
Ant
AAT
.
www.
pe
CT
muhay
1914
RUST
911
.
HI
JANGWA
.
W
A
BA
hr
VIVA
UX
2
.
.
27
.
.
ho
11
We
2.
W
AY
-
.
41
DAR
.
US
.
SEN
.
.
MW
RUSU
V
w
.
.
.
.
D
ir
Al
S
MU
meru.
SS
w
With
19HRN1
.
Udo
....
1
1.
20
1
5.
IND
VW
www
..
h
/
.
wana
/
AU!
22
A
W
1
ST
-
FIG. 200.-SYRINX OF Xenorhynchus senegalensis (AFTER BEDDARD).
198). In the former as well as in the latter the intrinsic
muscles are still absent, and there is a considerable modifi-
cation of the last tracheal rings; but in both there is a
partial deficiency of cartilage where the membrana tympani-
formis is developed in other birds. In Xenorhynchus this
" F. E. BEDDARD, ' A Note upon Dissura episcopus, &c., P. Z. S. 1896, p. 231.
.
HERODIONES
425
is but slight; in Abdimia and Dissura episcopus it is well
shown. But the latter bird has the complete bronchidesmus
which marks the ciconiine as contrasted with the ardeine
syrinx (cf. figs. 194 and 198). In Mycteria americana the
bronchial rings are complete, but thinner internally, which
is a hint of the otherwise absent membrana tympaniformis.
The genus Tantalus is unique among the Ciconiidæ in
having a convoluted trachea. This, however, is now known
to occur only in the male of T. ibis ; in both sexes of T.
loculator the trachea is unconvoluted. In the former bird
the tube makes several intrathoracic loops, as shown in the
figure (fig. 201). The syrinx is essentially stork-like.
In most storks the muscle formula of the leg is AXY +;2
the only exceptions to this yet known are Xenorhynchus
senegalensis, Dissura episcopus, and Abdimia sphenorhyncha,
where the ambiens is absent, and Leptoptilus crumeni-
ferus and argala, where there is no femorocaudal. The
tendency to an ardeine structure in the syrinx of these
birds has already been remarked upon, and may possibly be
correlated with the absence of the ambiens. Storks have
no biceps slip, but a typical expansor secundariorum. The
humeral head of the anconæus is generally present. The
patagial tendons are usually of a somewhat complicated
form.
The tensor patagii brevis is constituted upon a similar
plan in all storks, though there are naturally some little
differences in detail.
In Leptoptilus, according to WELDON,3 there is but one
tendon which, widening out just before its insertion on to
the fore arm, gives off a recurrent slip to the tendon of the
longus.
In Ciconia nigra, according to FÜRBRINGER, the tendons
.
o
1. On the Trachea of Tantalus,' &c., P. Z. S. 1878, p. 625 ; . On the Form
of the Trachea in certain Species of Storks and Spoonbills,' ibid. 1875, p. 297.
2 A. H. GARROD, 'Note on an Anatomical Peculiarity in certain Storks,
ibid. 1877, p. 711. In a specimen of Xenorhynchus australis a few fibres corre-
sponding to the accessory femorocaudal were found.
3 Loc. cit. (on p. 419).
426
STRUCTURE AND CLASSIFICATION OF BIRDS

NA
..
..
.-
'.
.
.
WA
.
wwlind
w
.
..
w
.
.
-
'
.
1
23
whe
.
-
/
..
-
www
.
•
SS
ll!
...
.th
11.
.
-
.
SSN
1
--
w
!
/
.
.
-
D
tu
-
::
..
'
-
*
.
-
!!
A
...
lr
12
KEY
LON
NI
.
l'ig. 201.- CONVOI.UTED WINDPIPE OF Tantalus ibis (AFTER GARROI)).
C', coracoid ; l, furcula ; st, sternum ; 7.0, 1.0, bronchi.
24
.
.
-
.-
-
.
.
-
.
AWY
A
.
NIM
23
.
.
-
-
-
-
.
-
--
IYA
..
.
..
1.
1
SKINS
-
.
-
.
S.
.
T-
.
.
.
.
.
TO
1.
.
Viis
SR
..
A
III
.
.
.
Z
:
27
CDR
.
*
NI
I
.
TES
.
.
.
.
-
-
.
SOVI
WITH
SNR
VAN
**
Si
W
WWW
N
j
.
ali
MAT
YI
.
.
Wint...1:
X
NA
.
?
O
1.
O
i
..
.
V
MAS
21
RY
..
TO
.
cil
.
13
Tahin:
ge
.
ANN
MW.
?
..
€
.
..
..
WA
1
23
..
IN
*
*
.
1901
2
2TAKT
L
NA
SSSSSS
*.
AVA
A
.
12.
Til
.
1
-
*
YA
.
.
.
.
7
EUR
,
th-
NA
1
CIIINNN
..
G
tc
.
-
.
-
..
-
.
.
Bu
NNNNN
S.-.
..
.
11
.
W
INV
.
...
SYARAK
.
.
-
.
-
IN
EN
7
IN
.
.
.
.
PE
-
SENSA
Uru
.
TAGS
RSS
ހަކަހަރި
es
W
SET
TY
XI
-
-
-
OLS
ENDUR
.
*
.
ESSEN
S
S
:
.
Fun
.
A
AR
.
'
.
2
.
.
11!!!!!
.
.
3
.
1
..
2
DIK.
.
.
11
-
.
.
2.
.
VVS
.
A
R
.
SHELDONDOLID
SU
1.
.
:
.
.
-
-
-
-
w
YARIS
OU
THI
I
WIND
9
..
INN
MA:
7
N-
XL
..
IZ
.
IL
I
+
.
LEO
HERODIONES
427
are a little more complicated. The tendon of the brevis is
obscurely divided into two from nearly its commencement;
the more anterior of these again divides into two, one of which
runs forward to be inserted on to the fore arm separately
from the hinder part, which remains continuous with the rest
of the tendon; there is a recurrent slip to longus.
In Abdimia the tendons are much the same; in both
these genera the propatagialis pectoralis of FÜRBRINGER IS
muscular.
In Tantalus leucocephalus the broad fascia-like tendon of
the brevis gives off a wristward slip, from the junction of
which with tendon of extensor matacarpi radialis a patagial
fan arises.
The pterylosis of the Ciconiidæ has been studied by
NITZSCH. The neck is continuously feathered down to
about the middle, where the spinal and ventral tracts
respectively become divided into two. The two spinal
tracts are narrow but strongly feathered, and cease abruptly
at about the end of the scapula ; after a short space they
recommence as a bifid but feebly feathered tract, the limbs
of which unite a little way in front of the oil gland. The
ventral tracts are broad upon the pectoral region but narrow
towards the vent.
In Pseudotantalus leucocephalus NITZSCH could not find
the aftershaft, but nevertheless one appears to exist.
In Mycteria and Leptoptilus argala the dorsal tract has
posteriorly no spinal space.
In L. argala NITZSCH states the aftershaft to be absent.
The oil gland has two apertures on each side in Ciconia
alba, five in C. nigra; L. argala has no less than six.
Anastomus coromandelicus has three ; Tantalus leucocephalus
has the same number.
The deep flexor tendons of the Ciconiidæ are constructed
on the plan of type I. In Tantalus leucocephalus there is a
slight variation; a small vinculum runs to flexor communis
before the latter divides into three, and then a broader vincu-
lum, chiefly going to tendon of digit II., but also slightly
to III. and IV., binds together the two tendons. In C.
Y
428
STRUCTURE AND CLASSIFICATION OF BIRDS
nigra there is the ordinary vinculum and a special slip to
digit II.
The lungs in the Ciconiidæ are at least often distinguish-
able from those of the Ardeidæ by the great deficiency of the
muscles arising from the ribs and attached to the pulmonary
aponeurosis. In Cancroma there were four pairs of such
muscles, arising from a corresponding number of ribs, in
Nycticorax five; but in Cicoria alba I only found one
pair inserted on to the aponeurosis in front of the septum
bounding the anterior intermediate air sac anteriorly. Pro-
fessor WELDON found no such muscles in a considerable
number of storks.
The tongue is always small. The proventriculus is
zonary. The liver is nearly equilobed, and there is always
a gall bladder. The intestinal measurements of a number of
species are as follows:-
-
-
-
-
-
-
-
S. I.
L. I.
--
-
-
-- ........
Ft. 11.
Inches
Iuches
4.9
Ciconia nigra .
, alba .
.
.
o a
3
6
aci ci cu cei
've
7.6
»
5
3
7
3
G
cici
maguari .. .
boyciana . .
Dissura episcopus . .
übdimia sphenorhynchus .
Mycteria americana. .
Xenorhynchus australis.
senegalensis
Leptoptilus crumeniferus .
i argala
Tantalus ibis . . .
1 loculator
aromi
od #ava 20
ci
8.5
6.5
5
6.6
-
..
.
-
- -
-
-
-
--
-
-
The number of cervical vertebræ is seventeen (Lepto-
ptilus, Tantalus) or eighteen (Xenorhynchus); the hypapo-
physes are feeble; there is a ventral canal formed by
union of catapophyses of 07-C11 (Xenorhynchus), C7-C12
(Tantalus). Four ribs reach the sternum in Xenorhynchus,
five in the others. The sternum has one pair of notches, and
the spina externa is absent or small. The procoracoid is of
fair size, but does not reach the clavicle; the coracoids meet
HERODIONES
429
at their sternal insertion in Leptoptilus. The hypoclei-
dium articulates with carina sterni. The skull is desmogna-
thous, holorhinal, and without basipterygoid processes; there
are in Tantalus rudiments of these processes in the shape of
a minute spine. The holorhinal character of the nostrils is
largely marked by ossifications of the alinasals; the nostrils
are thus much reduced in size, in a fashion suggestive of the
Steganopodes and possibly significant, but there is no bony
septum between them. This distinguishes the storks from
the herons, as does also the form of the palatines. These
bones are in the first place not cut off at right angles behind,
as in the herons, while the internal lamina only bounds the
interparietal space, and is at most (Xenorhynchus) carried
back to the end of the bones as a slight median keel. This
is absent in other storks. In Xenor hanchus and Leptoptilus
the palatines again approach each other, and are only sepa-
rated by the vomers just behind the maxillo-palatines. Oppo-
site to this point each palatine is produced into a strong
outwardly directed snag, large in Xenorhynchus, hardly indi-
cated in other storks. The interorbital septum is entire.
The large lacrymal is perforated or deeply notched for duct
of gland.
n
Y
Family Ardeidæ.—The herons contrast with the storks in
(1) the tracheo-bronchial syrinx always furnished with a
pair of intrinsic musclés, (2) non-division of pectoralis primus
into two layers, (3) invariable absence of ambiens, (4) pre-
sence of powder-down patches, (5) absence or weakness of
vinculum, (6) presence of a single cæcum only.
On the other hand the two families agree in (1) absence
of biceps slip to patagium, (2) presence of expansor secun-
dariorum, in addition, of course, to the points enumerated in
the definition of the group.
In Cancroma the oil gland is nude. The herons have
four or six powder-down tracts. Six are found in Cancroma,
Butorides atricapillus, Ardea cocoi, and other species ;
11
Not in Xenor lynchus and Dissura ; there is a trace of an overlap in
Abilimia, Tantalus, and Platalea.
430
CLASSIFICATION OF BIRDS
Y
STRUCTURE AND four in Ardetta and Botaurus. The number of rectrices differs
much; there are only eight in Ardetta exilis and A. involucris,
ten in Botaurus (not invariably), twelve in Ardea cocoi and
Cancroma cochlearia.
The pterylosis differs from that of the storks by the
narrowness of the tracts. The spinal space begins with the
commencement of the neck, and only terminates a little way
in front of the tufted oil gland. The anterior part of the
spinal tract is not always more strongly feathered than the
posterior part, and there is (according to the figures of
NITZSCH) hardly a break between them. The ventral tracts
also are separate early on the neck. In Cancroma they divide
on the breast into a broader, stronger outer tract, which ceases
just below the metapatagium, and a narrow inner tract. The
anterior ventral powder-down patches constantly interrupt
the continuity of the anterior and posterior sections of the
ventral tracts.
--
-
-
-
-
Small
Intestine
Large
Intestine
i
-.
Cæcuu
-
.
--
--
-
.
-
-
'.
.
-
.
-
-
.
90
-
-...--.-
--
.25
•15
•15
-
-
--
Ardea Goliath .
sulinairana
pirpatrea
сосой
egretta .
-
1.5
-
--
..--
-
-
-
--
-
..
1.5
•25
.
-
-
-
-
-
-
•15
-
-
25
-
-
, garzetta . .
Bitorides atricapilius
, cyanurus.
Ardetta involucris.
Nycticorax caledonicus
30
15
3.6
3.5
2.25
3.5
22:5
40
.15
33
•14
violaceus.
Tigrisoma brasilien.se
Cancrorna cochlearia
Botaurus stellaris .
33
Co
•15
51
hean
•15
-
-
:
-
-
-...
-
A curious absence of any apparent relationship between
the relative length of the sections of the alimentary canal,
and of the alimentary canal as a whole, and of the food, is
shown by the above table, drawn up by Mr. GARROD,
which I reproduce here from his notes.
They seem, however, to ally the last four genera, which
HERODÍONES
431
22
USD
have a long large intestine. As a rule the left lobe of the
liver is the smaller, while in the storks the lobes are equal.
A gall bladder is always present except in Botaurus stellaris.
The cæcum is single, and, as will be seen from above
measurements, rudimentary.
The carotids are, as a rule, two, and separate ; but in
Botaurus they fuse, and in Ardetta involucris the right only
is present.
Of the leg muscles the ambiens is always absent, and the
formula is typically AXY-. The femorocaudal is never
strong, and is particularly slender in Ardea Goliath,In A.
sumatrana, A. ludoviciana, Nycticorax Gardeni, Cancroma
cochlearia, and Tigrisoira brasiliense it is totally absent.
The deep plantar tendons are characteristic; there is
almost always a very slender vinculum between the two,
which is totally wanting in Botaurus stellaris, Ardetta
involucris, and A. exilis.
The tensores patagii are stork-like. The tendon of the
brevis bifurcates, and from the point where the anterior
limb is inserted on to tendon of extensor of fore arm a
recurrent slip is given off to longus. This arrangement
holds good for Ardea purpurea, A. Goliath, Cancroma
cochlearia, and Nycticorax griseus; but in Cancroma the
recurrent slip is sometimes absent. The pectoralis abdomi-
nalis is present, and thus serves to differentiate them from
the storks, ibises, and spoonbills, in which the muscle is
absent.
The skull of the Ardeidæ has been chiefly studied by
SHUFELDT.2 In the more normal forins (e.g. Ardea cinerea,
Butorides cyanurus) the skull is holorhinal, the holorhiny
not being obscured-as it is often among the storks-by
the irregular ossification of alinasals. The vomer is well
developed, much compressed laterally, and largely double.
The maxillo-palatines are spongy bones, largely free
from each other posteriorly. The palatines (see fig. 202)
Y
t.
1
I
.
Sometimes absent in this species.
2Osteological Studies of the Subfamily Ardeinæ,' Journ. Comp. Med. and
Surg. 1889.
432
STRUCTURE AND CLASSIFICATION OF BIRDS
ܕܵܢܵ
-
-
V
-
-
-
UN
Hote:
SHA
S
1
sem
-
-
>
are very straight bones, usually cut very squarely behind,
but notched postero-laterally in Ardea bubulcus, A. minuta,
A. comata, with well-marked internal laminæ, which extend
quite to the posterior end of the bone. The interorbital
septum is largely fenestrate. The bony ectethmoids are but
little developed; Cancroma is in
several ways rather anomalous. It
is heron-like in the fenestrated in-
terorbital septum, and in the fact
that the internal lamina of each
МІxp
palatine is continuous to the posterior
end of that bone. The nostrils are
continued forward by a deeper groove
than that which is formed in the more
normal herons--a point of likeness
this to Scopus and Balæniceps (qq.v.)
The very broad palatines join the
vomer again in front of their posterior
junction with each other, thus divid-
ing the interpalatine vacuity into two
areas. It is thus to a certain degree
'doubly desmognathous,' and is so
far like Xenorhynchus (see p. 429).
There is a well-marked lateral process
of the palatines, as in Scopus and
storks.
As in Scopus the procoracoid
FIG. 202.-VENTRAL SUR- is very small and the coracoids overlap
FACE OF SKULL OF Ardea
cinerea (AFTER HUXLEY). each other at their insertion. Like
Pł, pterygoids ; PI, palatines ; l'o, the storks, and unlike Scopus, the
vomer ; ArxP, maxillo-palatincs.
hypocleidium articulates with the end
of the carina sterni. The hypocleidium, moreover, projects
backwards between the two clavicles as a narrowish piece.
The hæmapophyses of the cervical and dorsal vertebre
are small, those of the latter being sometimes quite absent.
There is a catapophysial canal (in Cancroma as well as
Ardea), formed in the two types mentioned by cervical
vertebræ 7-12.

M3
Dec
'
TE
..
AP
IL21
DIA
Court
.
HERODIONES
433
Family Balænicepidæ.— The great 'whale head' of Africa,
Balaniceps rex, requires further study before its exact
position can be determined. It is admittedly a member of
the present group, though its original describer, GOULD,
regarded it as a pelican. We know the skeleton through the
labours of PARKER, while our at present scanty know-


.
.
JOTTO
Pe
.
murattini
wwungTROMU
urrent TAN
1
..
Out
..
MS
101
111
IVUL
hlution
on
KO
Stutt
UUNI
ARVU
.
11
UNAMIN
1......
annat
nh
nu
.
1.
.
tutto
MUR
AUDI
US
UN
VA
CON
TERTUNTUT
XR
.
..
undMANNITUS
AAC
A
.
2
12
.
00157
Fig. 203. -SYRINX OF Balcriceps.
FRONT VIEW. (AFTER BEDDARD.)
b, free margin of bronchidesmus.
Fig. 204.—THE SAME. BACK VIEW.
(AFTER BEDDARD.)
ledge of the soft parts is due to myself.3 Its powder-down
patches were discovered by BARTLETT.4 As in the herons
also the right lobe of the liver is the largest, and the cæcum
is single. The syrinx (see figs. 203-205) is ardeine in form, but
lacks the intrinsic muscles. These, however, are not en-
Not a serious mistake in view of the admitted relationships between the
Steganopodes and Herodiones.
2"On the Osteology of Balæniceps rex,' Trans. Zool. Soc. iv. p. 269
(abstr. in P.Z. S. 1860, p. 324).
3.On certain Points in the Visceral Anatomy of Balaniceps bearing upon
its Affinities,' P. 2. S. 1888, p. 284.
4. On the Affinities of Balaniceps,' ibid. 1861, p. 131. See also REIN-
HARDT, 'On the Affinities of Balaniceps,' ibid. 1860, p. 377, and GIEBEL, ' Ueber
Balæniceps rex,' Zeitschr. f. d. ges. Nat. lxi. 1873, p. 350.
FF
434
STRUCTURE AND CLASSIFICATION OF BIRDS
11
CA
1
n
.
-
S
ANOM
.
t
ADI
Villa
141
MINIM
JI
WIN
)
tirely absent; their former presence is indicated by a narrow
ligament on each side (fig. 42, p. 62), which occupies the place
that a muscle should, and is attached precisely where the
intrinsic muscles are attached in other Ardeidæ. The mem-
brana tympaniformis is well formed, the bronchidesmus is
incomplete, while the general form of the organ is purely
tracheo-bronchial and thoroughly ardeine. This will be
apparent from the annexed woodcuts.
The nearest relations of Balaniceps,' said PARKER, ' are
the South American boatbill (Can-
croma cochlearia) and the little
South African umbre (Scopus um-
bretta). The interorbital septum is
stork-like in its completeness. The
lacrymal, as in Scopus alone among
Herodiones, reaches as far down as
the quadrate jugal bar, but it is fused
anteriorly with the walls of the
skull. The nostrils are continued
forward by a groove precisely like
that of Scopus and Cancroma. In
FIG. 205.-SYRINX OF Bala- the palatine bones the fusion of the
riceps, ARRANGED TO DISPLAY
PESSULUS AND MEMBRANA internal laminæ to form a median
TYMPANIFORMIS (AFTER BED- keel behind the interparietal space
DARD).
is precisely like Scopus ; so, too, is
the lateral angle of these bones (see p. 422). There is a firm
synostosis between the furcula and the carina sterni.
Cervical vertebræ 7–13 have, as in most other Herodiones
(excluding, however, the supposed ally of Balaniceps, Scopus),
a ventral catapophysial canal.

****
11..
**
.
S
W
.
..
**
MU
9
TAYA
th
WWWWWWWW
NA
at!
NO
N
The family Plataleidæ includes not only the spoonbills
NITZSCH to the group'on account of the surprising small-
ness of their tongues.'
The pterylosis is exactly as in the storks. The rectrices
1 According to NITZSCH It appeared to me (in Platalea rosea) to be more
like that of Tantalus loculator, in that the hinder part of the spinal tract was
not bifid, but continuously though sparsely feathered.
HERODIONES
435
TTT
1
11
N1
LOU
1
CU UIT
are twelve. The oil gland of Platalea leucorodia has three
distinct orifices on each half, that of Ibis only one. The
long downwardly bent bill of the ibises distinguishes them
from the storks and suggests Numenius. NITZSCH, indeed,
regarded the birds as intermediate between the two groups
represented by these types.
The tensores patagii have always a biceps slip running to
the tendon of the longus, and there is a patagial fan.
In Ibis ethiopica the tendon of the tensor brevis is
simple and rather diffuse. In Eudocimus ruber and G. mela-
nopis the tendon gives off a distinct wristward slip, while the
patagial fan is formed of two rather separate strands, with
the posterior of which, rather high up, the wristward slip
fuses in Geronticus melanopis.
In Platalea the muscle and its tendons are much the
same, but the brevis is very broad and fascia-like.
The muscle formula of the leg is complete (i.e. ABXY+)
in all Plataleidæ.
The plantar tendons are connected by a vinculum which
in Eudocimus ruber extends on to the special slip to digit II.
By the division of this vinculum may have arisen the two
vincula of Ciconic nigra (see above, p. 427).
The liver is equilobed (I. ethiopica), or the right is a
little larger (E. ruber). A gall bladder is present. The
following are intestinal measurements :-
S. I.
l
L. I.
Eudocimus ruber
.
.
31
1.6
62
•35
•25 1
•12
10
Nipponic Terrininckii
Plegadis falcinellus .
Ibis cethiopica . .
» strictipennis
Platalea leucorodia
» cijaja . .
36
•12
.
The intestinal convolutions of Platalea leucorodia are
shown in fig. 207. The greater part of the gut has preserved
1 HUNTER, in Essays and Observations (ed. Owen, London), 1861, writes of
this species : The cæca are about four inches long and very small, attached to
the ileum their whole length.'
FF 2
436
STRUCTURE AND CLASSIFICATION OF BIRDS
the primitive arrangement. The duodenal loop is curved,
and in other storks (s.s.) this (cf. fig. 208) is converted into a
spiral. There is a tendency, in fact, among the Ciconiidæ

..
.
EE
'
B
.
.
ht:
III
-
-
.
S
.
VN
T-IT
ww
ESCA
w
WS
h
*.1111
MWAIDS.
*
.
Dhi. WICI!
WA
.
INT
liEANID
X
Y
20
-
IXA
S-
1
TAR
NO
111
2
ri."
SITY
A
1
CNN
.
TY
W
Link
UN
12
A
HA11
M
CALLINN
A
E
-
2
(
4
.
-
SU
SHE
EEN
TT
ER
.
SSS
w
27
iti
.
ta
Ditt
.
EN
VIV13
.
.
27
20
*
N6
LTZU14
12
S
2.
.
3
U
is.
The
or
2.
wa
WA
www
.
39
Shar
ws
.
..
.
..
I
.
.
.
S
.
.
-
.
*.
.
Sr
.
W
-
.
-
2
--
*
.
.
.
WE
11
ci
w
.
..
Z
.
.
G
**
PP-
.-
.
-
-
*
-
.
-
WIZ
-
33
Sis
ih
.
Si
-
-
a
.
++
.
LSIS
s..
AI:11
...
.
W
.
gitti
IS
Fig. 206.-WINDPIPE OF Platalea ajaja (AFTER GARROD).
a, trachea ; 0, bifurcation of bronchi in front of sternum ; 9.6, 1.6, bronchi; d, esophagus
C, cervical muscles.
HERODIONES
437
JUI
to the formation of these spirals, which are also found in the
Accipitres.
The windpipe in the ibises is simple, not convoluted;

LLENDE
TRARED200A
FIG. 207.--- INTESTINES or Platalea leucorodia (AFTER MITCHELL).
t, short-circuitiug vessel divided.
but in Platalea leucorodia it is convoluted. In this bird
the windpipe runs in a straight or slightly sinuous course

TIPYN
FIG. 208.—INTESTINES OF Ciconia nigra (AFTER MITCHELL). **
X, as in fig. 207.
into the thorax; it then bends upon itself, and after an inch
and a half or so reverts to its original direction, and divides
within the thorax into the two bronchi.
'I have a windpipe of P. leucorodia which is not convoluted, but which
bifurcates within the thorax.
438
STRUCTURE AND CLASSIFICATION OF BIRDS
In Platalea ajaja (see fig. 206) the trachea is peculiar
in that its bifurcation takes place about the middle of the
neck, some distance at any rate before the entry of the
bronchi into the thoracic cavity.
In a female which I measured the bifurcation was three
inches in front of sternum, and the distance from the bifurca-
tion to the end of the larynx was six and a quarter inches.
HUDSON has stated 1 that there are two species of spoonbill
in the Argentine : one has a windpipe like that figured above,
and may be considered to be the true ajaja, while the other
has a windpipe which is not modified in any way. The
characters of the latter—apart from the question of the
windpipe-have been considered by some to be those of
immaturity ; but this is denied by HUDSON.
I have in my possession seven windpipes of P. ajaja, of
which two are males and the rest females. In the two males
the lengths of the trachea are practically identical. In the
females the position of the syrinx varies considerably, being
more than an inch lower in some than in others; this may
possibly account for the differences observed by Mr.
HUDSON.
The extrinsic muscles of this species arise from inner side
of coracoid, not far from the middle line of sternum. The
intrinsic muscles of the syrinx are present; they cease, how-
ever, some little way in front of the syrinx. These muscles
are also inconspicuous, and form a very thin though rather
wide band. The syrinx is not especially stork-like, except in
the fact that the bronchi are for the greater part of their
extent tubes with complete rings. The first dozen or so,
however, are incomplete, there being thus a membrana
tympaniformis.
There is a cartilaginous three-way piece, and generally
there is but little ossification in the windpipe.
The windpipe of P. alba is different from both the species
already described.
It is not convoluted, but the bifurcation does not take
place outside of the thoracic cavity, as in the last species. It
SCLATER and Hudson, Argentine Ornithology, vol. ii. p. 115.
HERODIONES
439
is also stork-like in the fact that there is no membrana tym-
paniformis; the bronchial rings are complete rings from the
very first.
The main peculiarity of the windpipe, however, lies in
the fact that from a point about three inches from the larynx
it appears to bifurcate and to consist of two closely applied
tubes. By cutting windows it was ascertained that this
appearance corresponded to the reality--that the windpipe
did consist of two tubes. This arrangement, which seems to
characterise the present species only, is, of course, suggestive
of the median tracheal septum of the penguins, &c.1
Of the ibises I have examined the windpipe of Eudocimus
ruber, E. alba, and of Ibis ethiopica. There are differences
between the species similar to those which exist between the
species of Platalea. In Ibis ethiopica there is no membrana
tympaniformis, the bronchial rings being complete. In the two
other species this structure is present, and moreover the last
few tracheal rings are defective in the middle line posteriorly.
The extrinsic pair of muscles are attached in E. ruber to
the inner surface of sternum not far from the middle line.
The intrinsic muscles stop short some way in front of the
syrinx.
In Platalea ajaja cervical vertebræ 7-10 have a cata-
pophysial canal. Some of the dorsal vertebræ are fused.
The number of cervical vertebræ is seventeen or eighteen
(Platalea ajaja). The sternum is two-notched (Platalea)
and has a small spina externa, but no spina interna.
The skull has, as in charadriiform birds, a pair of
occipital vacuities.
It is schizorhinal and has rudimentary basipterygoid
processes, which in Platalea ajaja have the form of small
sharp thorns. Supra-orbital impressions are feebly developed.
The lacrymals with the ectethmoids very nearly form a com-
plete ring of bone, the aspect of this part of the skull being
1 Gadow, in NEWTON's Dict. Birds, speaks of the trachea (sub voce) of Platalea
as divided by a cartilaginous septum. I have not found this to be the case
with P. ajaja or P. leucorodia.
? Also, however, in geese.
440
STRUCTURE AND CLASSIFICATION OF BIRDS
the
distinctly charadriine. A groove runs forward from
nostrils, as in Scopus, &c. (9.v.)
Family Phænicopteridæ.1Phoenicopterus agrees with
the storks in the subdivision of the prebronchial air sacs by
many septa into smaller chambers. But, as this also occurs


Ac
222
SINUN
2141
ADITIV
.
Fig. 209.-SYRINX OF Plicericopterus (AFTER WELDON).
la, front view; ac, lateral view.
in Chauna and to a much greater extent, less weight must
be laid upon it than upon some of the muscular characters.
In the storks, as in Scopus, but not the Anatidæ, the pec-
toralis major is divided into two distinct layers. This is also
the case with Phænicopterus. The tensores patagii are
closely similar in the birds under comparison and diverge
from those of the duck. The ducks are peculiar in the origin
of the smallest head of the gastrocnemius from the biceps;
Our knowledge of the anatomy of the soft parts' of Phoenicopterus is
mainly due to WELDON (P. Z. S. 1883) and to GADOW (Journ. f. Onn. XXV.
p. 382.)
HERODIONES
441
VA
no such connection occurs in either stork or flamingo. That
the deep flexor tendons of Phænicopterus are not stork-like is
surely related to the diminutive hallux of that genus.
On the other hand the accessory femorocaudal, though
small, is present in the flamingo, though absent in the storks,
while the syrinx (fig. 209) is not stork-like. The cæca are
long (three inches), but the intestines are not duck-like.
The atlas is notched by the odontoid process, and the
notch is very nearly converted into a foramen. There are
nineteen cervical vertebræ. None of the catapophyses fuse
to form a canal. The transition between catapophyses and
hæmapophyses is more complete than in most birds ; on the
last cervical the two catapophyses are raised on a common
platform, and on the first dorsal is the first (and last) hæma-
pophysis, which is flattened and obscurely bifid. The last
cervical and the first three dorsals are fused. Five ribs
reach the single-notched sternum. The coracoids overlap at
their insertion.
The skull is desmognathous, with basipterygoid processes,
to which the anterior ends of the pterygoids are attached.
It is holorhinal with pervious nostrils. There are lateral
occipital fontanelles. The lacrymals are large and rather
duck-like, notched externally; they nearly reach the jugal
bar. There are no ossified ectethmoids.
In including the Plataleida and Ibididae with the Hero-
diones I shall have the assent of most ornithologists. Alone
among recent observers who have occupied themselves with
the structure of the group, GARROD and FORBES placed the
spoonbills and ibises apart. The latter included them in his
group Pluviales with the Charadrii, Rhinochetus, &c. These
diverse opinions about the Plataleidæ appear to me to be
largely due to the primitive position which they occupy
among the Herodiones. They are to my thinking not far from
a basal gralline' stock. The Plataleidæ have the complete
muscle formula, and the biceps slip to the patagium. Some of
these muscles have been lost in the other Herodiones, in which
With the partial exception noted on p. 425, footnote.
442
STRUCTURE AND CLASSIFICATION OF BIRDS
there is traceable a gradual series of modifications. In the
storks the accessory femorocaudal is always absent, and in
some the ambiens and femorocaudal also ; in the Ardeidæ both
ambiens and accessory femorocaudal are gone, and the
modification of these leg muscles culminates in the aberrant
Cancroma, where the formula is merely XY-. In the
Plataleidæ (as in Tantalus) there are just faint traces of the
basipterygoid processes, missing elsewhere in the group.
The ibises are schizorhinal, and in Platalea the ends of the
nasal grooves are rounded, thus tending towards the holo-
rhinal, while the lower part of the bony nostril is wider than
the upper, appearing thus to show a commencing occlusion
of the schizorhinal nostril into a holorhinal one ; in Ardea
cinerea a faint trace of a former schizorhinal condition is
seen in a slight groove which runs back from the end of the
holorhinal nostril, as in Chunga (see p. 144). The schizo-
rhinal condition, as has been before pointed out, is probably
the more archaic. Finally the Plataleidæ have, according
to MITCHELL, the most primitive form of gut among the
Herodiones. Significant points of likeness between the
Plataleidæ and Grues are not wanting; the occipital foramina
and the impressions of the supra-orbital glands were among
the facts that led FORBES to associate them together. The
convoluted windpipe is common to Platalea, Tantalus, and
Grus. Both Platalea and Grus have the complete muscle
formula and schizorhinal nostrils.
It has been often asserted that there are likenesses
between the Herodiones and the accipitrine birds. This
largely reduces itself to a comparison between the Herodiones
on the one hand and the Cathartidæ and Serpentarius on
the other; for if the two latter forms of accipitrine birds are
rightly so placed the falcons must, on account of the various
reductions in their structure, be derived from some form near
to these, and cannot be their ancestors. There are two at
first sight rather striking likenesses between the Herodiones
and these lower accipitrines. GADOW has commented upon
resemblances in the lie of the intestines, and MITCHELL has
still further emphasised this likeness. In both groups (the
HERODIONES
443
falcons only among the Accipitres were examined) there is a
tendency for the intestine to be thrown into spirally twisted
loops; but MITCHELL is of opinion that this is really no
more than a convergent resemblance, for as the simpler
types are considered the spiral arrangement becomes less
and less obvious, thus indicating its special development, and
independent development, in both.
: The second point concerns the syrinx, which as a special-
ised organ is wanting in both storks and Cathartidæ. In
neither group are there intrinsic muscles. This point of
resemblance rests, however, upon mere negativity. The
details of the conformation of the lower part of the larynx
are, as may be inferred from the preceding explanations and
figures, extremely different in both; it seems as if the syrinx
has degenerated in both, but along quite different lines, the
loss of the intrinsic muscles being about the only point in
common. And we know from other groups that this muscle
may be independently lost. There is, to my mind, as much
to be said for a derivation of the Accipitres from the crane as
from the pelargine stock, the fact being that we must
probably seek for the origin of both from a low branch,
perhaps common to all. The matter is further dealt with
under the section devoted to the Grues.
The skull of the flamingo is not duck-like. The back
view of it, with the occipital fontanelles, might, it is true, be
mistaken for that of an anserine bird; but there are no
salient likenesses elsewhere. There are but rudimentary
basipterygoid facets, and the palatines have (which they
have not in the duck tribe) a well-developed internal lamina,
which, as is so often the case, is sharply bent downwards at
its edge. In front of the fused maxillo-palatines there is no
palatal vacuity, as in nearly all Anseres. The lacrymals,
like those of the Anseres, are certainly large ; but their size is
not so conspicuously marked in the length of their base of
attachment to the margin of the orbit as in the length and
great breadth of the descending process, not a feature of the
anserine skull. The ectethmoids seem hardly ossified. The
interorbital septum is largely deficient in front, as in Chauna,
444
OF BIRDS
-
STRUCTURE AND CLASSIFICATION but is also more vacuolated behind, and in a different way from
what is found among the few Anseres in which the inter-
orbital septum is not solid. The length of the angular
process of the mandible, though a duck character, is also
found in the Plataleida. There are so many characteristic
duck-like characters wanting in the skull of Phænicopterus
that we cannot place it with that group.
Of fossil Herodiones a considerable number of genera and
to cave deposits, and have been found in Europe, India,
by DAMES, from the Cretaceous of Sweden, be really an
ally of the flamingo-like bird Palclodus, it is important to
note that this family goes back further into the past than
any other living family, so far as our information allows us
to say. HUXLEY'S name of ' Amphimorphæ’ for the group,
and his remark to the effect that they are so thoroughly
intermediate between the storks and ducks, will occur to the
mind in this connection. This bird is known by a scapula,
coracoid, and humerus.
The other forms upon which new genera have been founded
are not known by even so much as the scanty remains of Scanior-
by the tarso-metatarsus (incomplete), while the other genera are
founded upon equally fragmentary remains. Tantalus Milne-
Edwardsiz ? (nearly perfect tibio-tarsus), from middle Miocene,
France. Palelodus, however, is known by coracoid, scapula, and
some of the 'long bones,' as well as the sternum, 'scarcely to be
distinguished from the somewhat larger sternum of Phænicopterus
l'oscus,' furcula, one or two vertebræ, and metacarpal bones. The
bird seems not to have had such long legs as the modern flamingo,
but longer toes. Elornis (Eocene and Miccene) was also a
flamingo, but intermediate in the length of its legs between
Phænicopterus and Palalodus. Agnopterus (Miocene) is reckoned
a flamingo by FÜRBRINGER, placed'incerte sedis' by LYDEKKER.
TÜber Vogelreste aus dem Saltholmskalk von Limhamn bei Malmö,' Bih. K.
Svensk. Ak. Hardl. xvi. 1891.
2 SHUFELDT, 'Fossil Bones of Birds,' &c., P. Acad. Nat. Sci. Philad. 1896,
p. 507.
TUBINARES
.
445
TUBINARES
Definition.--Nostrils produced into tubes. Aftershaft present, aquinto-
cubital. Oil gland tufted. Skull schizognathous, holorhinal.
Two carotids present. Large supra-orbital glands.
V
CU
In
The peculiar form of the external nares, which has given
to the group its name, characterises it. It is a character
which is found in no other group, but in all members of
the present. The Tubinares are nearly the only large group
of birds which can thus be diagnosed by a single character.
The tube itself is, according to FORBES, whose Challenger'
memoir upon the group forms the chief classic upon the
subject, in Majaqueus, and probably in other genera,
caused by a growth of the catilaginous walls of the nasal
sacs. The degree of fusion between the two tubes varies in
different genera. In Procellaria, for example, they quite
coalesce and the external aperture is single. In Pelecanoides
there is a distinct and not broad septum; while in Bulweria
and others the septum is so broad that the tubes almost
appear double.
The petrels are web-footed birds with a small hallux,
which in Pelecanoides is quite absent. The web does not
take in the rudimentary hallux. The general number of the
rectrices is twelve, but Ossifraga has as many as sixteen.
The aftershaft is always present. The pterylosis does not
vary greatly; the dorsal and ventral tracts are well separated
upon the neck. The ventral pteryla is divided on the
neck; in the pectoral region each branch again divides.
The dorsal tract divides at the middle of the scapulæ into
two, which unite later, thus enclosing a space.
• The tongue varies much in size and in the amount of its
spiny bordering or covering. In Diomedea, for instance, it is
much covered superiorly with spines. In (Estrelata and
others the tongue has a bordering of spines which are lateral
1 It has been pointed out that the complex and somewhat protuberant
nostrils of Chionis bear a little resemblance to those of the Tubinares, but are
differently developed.
446
STRUCTURE AND CLASSIFICATION OF BIRDS
pole
".
as well as posterior; in Daption capensis, and in many
others, the spines are confined to the hind margin of the
organ. The more usual condition is the intermediate
form.
There is a well-developed but small.gizzard present.
The cæca are absent in the Oceanitidæ, but present, as a
rule, in the Procellariidæ ; they are small and nipple-like,
and in Cymochorea appear to be reduced to a single cæcum.
The gall bladder is
always present, and the
lobes of the liver are
equal or nearly so. The
arrangement of the
intestine is shown in
fig. 210. The duodenal
loop is double; the
greater part of the in-
testine is drawn out into
a considerable number
of straightish loops.
As to muscular
anatomy, the great
FIG. 210.—INTESTINES or Fulinarus glacici- pectoral is divisible into
lis (AFTER MITCHELL).
two layers by an inter-
2, short-circuiting vessel divided.
posed tendon, asin storks
and Steganopodes. But in Larus, according to FÜRBRINGER
(and in Podica also), the same division occurs, which tends
to lessen the differences between the Tubinares and the
Laridæ, so insisted upon by GARROD, FORBES, and some
others. The tensores patagii in the Tubinares are com-
plicated, but not in all the genera. In the Oceanitidæ they
are simplest. In these petrels the tensor brevis is a simple
tendon. In Pelecanoides, and in some others, there is the
additional complication that the tendon bifurcates near to
its attachment on the extensor tendon, and gives off an
anterior slip inserted more wristwards. In Prion affairs
are still further complicated by the metamorphosis into
tendon of the whole of the extensor metacarpi radialis

:
.
......
MIT
.
TUBINARES
447
superficialis. In (Estrelata brevirostris we first meet with
a recurrent slip going to the longus tendon and arising
from the brevis in front of the termination of its anterior
branch. The more typical tubinarian arrangement is seen
in Estrelata Lessori. We find here the characteristic
ossicle of the tendon of the brevis which is found in
so many Tubinares, and which has been held by some to
be a character of much systematic importance in differen-
tiating the group-a character which FÜRBRINGER thinks
has been 'overvalued.'! From this ossicle' spring some
of the fibres of the extensor muscle of the fore arm ; it is
also the starting point of the recurrent tendinous fibres,
which unite the brevis and longus tendons; these tendons
are, moreover, in close apposition for nearly the whole of
their course--itself a characteristic feature of the Tubinares.
In Ossifraga and in some other genera there are no
ossicles, but the tendons are highly complicated. In some
petrels-for instance, in Diomedea exsulans—the wing sesa-
moid is double, and in this bird also there are considerable
complications of the various tendons. While, therefore, we
cannot define the petrels by the arrangement of the tendons
of the tensores, as is sometimes possible, it is evident that
we have what might be expected in a large and important
group-a very considerable series of modifications of these
organs. No petrel has, strictly speaking, a biceps slip, and
the biceps itself, though perfectly normal in origin and
insertion, has much more largely degenerated into tendon
than is usual for this muscle. There is, however, a curious
modification of this muscle in Pelecanoides and in a few
others. Here the coracoidal head alone forms the muscle ;
the humeral head goes entirely to the tensor patagii longus;
this slip is, therefore, as FORBES remarks, 'functionally, a
biceps slip.' Something apparently representing the true
biceps slip is occasionally found in the Tubinares. In a
few there is a tendon derivable from the humeral head of the
I Justly, as it is found not only among the Steganopodes, which may be
fairly regarded as allies of the Tubinares, but also in so lernote a type as
Morops !
448
STRUCTURE AND CLASSIFICATION OF BIRDS
biceps, which appears to end on the fascia of the wing. 1
The expansor secundariorum, found only among the
Oceanitidæ, is peculiar in that it arises from the surface of
the pectoral ; its muscular belly is, as usual, at the elbow,
and the tendon is joined by a branch from the scapularies.
The aircon@us has a well-marked tendinous attachment to
the humerus.
The muscles of the hind limb, to which GARROD attached
so much classificatory importance, vary much in the group.
The ambiens is present in all except Fregetta and Pele-
canoides. In Garrodia and some others the tendon does
not cross the knee. All have a femorocaudal, but the
accessory is absent in Bulweria and Pelecanoides. The
semitendinosus has an accessory in the Oceanitidæ, but not
in the others. It is inserted separately from the semi-
membranosus. The deep flexor's blend about halfway down
the leg ; but when a hallux is present it receives no slip
from the conjoined tendons. The syrinx of the Tubinares
shows an interesting series of gradations, from a quite
ordinary tracheo-bronchial type to what is very much like the
bronchial syrinx of the Caprimulgidæ, though FÜRBRINGER,
while admitting the 'bronchophone tendency of the syrinx
of the Strigidæ, as a point of similarity between that group
and the Caprimulgidæ, considers that only 'artificially' can
the Tubinares and the Spheniscidæ be brought into the same
line. Nevertheless in the series of Tubinares the bronchial
rings to which the intrinsic muscles are attached seem to
move further down. FORBES, however, regards this as a
splitting of the trachea, and holds that the intrinsic muscles
are invariably fastened to the fifth semi-ring. “It is in the
genus Pelecanoides,' remarks FORBES, 'that the typical
construction of the syrinx of the Tubinares is seen in its
simplest fcrm. In this bird all the bronchial rings are
semi-rings, and there is a three-way piece of the usual
r
In a specimen of Nycticorax griseus on one side of the body I found a
tendon from the biceps running to the tensor brevis tendon, which may be com-
parable to the above-described slip.
2 Cf. as to this Opisthocomus, Edicieinus, and Casuarius.
TUBINARES
449
· structure. In Garrodia the first three bronchial rings are
complete. In Thalasseca glacialoides the last four tracheal
rings are incomplete behind, and are quite like the four
succeeding bronchial semi-rings, being, moreover, like them,

-

777
.
:-
3.
-
Map
Mæp
M
min
T
O
.
AL
-
"
- -
1-
.
.
1
ande
TE
2
*-
Fig. 211.-SKULL OF Diomedea exularis
(AFTER HUXLEY).
Vo, vomer; Mxp, maxillo palatines ; Pt, pterygoid.
Fig. 212.-SKULL OF Procellaria
gigantea (AFTER HUXLEY).
Pl, palatines ; * basipterygoid process.
Other letters as in fig. 211.
ossified. This modification is carried to its furthest extreme
in Ossifraga. In this petrel the last nine or ten tracheal
rings are incomplete in front, and the last twelve or so are
incomplete behind. Thus the membrana tympaniformis
does not commence for some distance away from the bifur-
cation of the respiratory tube, the rings being double and
GG
450
STRUCTURE AND CLASSIFICATION OF BIRDS
complete for the same way in front of it. The division of
the trachea is carried upwards above the point where it is
externally divided into two tubes by an internal septum.
And in Acipetes, though there is no external division of
the trachea, there is an incomplete internal septum. In
Diomedea, according to SWINHOE, at any rate in two
species, the bronchi are long and convoluted, as in certain
storks.
The petrels are schizognathous and holorhinal birds,
some with basipterygoid processes. The skull possesses a
small peculiar bone, which has been termed the 'ossiculum
lacrymo-palatinum,'? whose relations are sufficiently in-
dicated by its name. This bone occurs in many genera ;
but it is said to be of no great classificatory significance, 2-
since it also occurs in birds so remote from the petrels and
from each other as Cuculidæ, Cariama, and Laridæ. The
skull is markedly excavate above the orbits for the supra-
orbital glands. The skull of an albatross (Diomedea melano-
phrys) is in more than one particular like that of the
steganopods. It is, it is true, schizognathous; but the
interval separating the maxillo-palatines and the palatine
expansions of the maxillæ in front of these is very slight;
and, as FORBES has observed, the downwardly curved
extremity of the vomer partly fills up this gap, though there
is no actual fusion between it and the maxillo-palatines.
The hooked bill is Fregata-like; and the closely approxi-
mated and downwardly produced internal laminæ of the
palatines are highly suggestive of the pelican. There are
always fifteen cervical vertebre. The sternum varies so
much, from having a plain hinder contour to the presence of
two notches on each side, that its characters need not be
given in detail.
The petrels can be divided into two families, the
Oceanitidæ and the Procellariidæ, which may be thus
defined :-
A
| By BRANDT. PARKER has termed it uncinate.'
? See, however, under Steganopodes, p. 416.
TUBINARES
451
.
Oceanitidæ.
Tarsi ocreate or covered by large transversely
oblique scutes anteriorly. No cæca. Expansor
secundariorum present. Accessory senvitendinosus
present. Ambiens (when present) does not pass
over knee. Wing shorter than leg.
Procellariidæ.
Tarsi covered with hexagonal scutella. Cæca
present (except in Halocyptena). No expansor
secundariorum 01 accessory semitendinosus.
Ambiens (absent in Pelecanoides) crosses knee.
Leg shorter than wing.
Not many fossil Tubinares are known. If Hydrornis natator
of MILNE-EDWARDS, from the lower Miocene of France, be referable
to this group, it has a considerable antiquity. Diomedea anglica
has been lately described by LYDEKKER.)
The nearest allies of the petrels appear to be the
Steganopodes (q.v.)
LUU
PALAMEDEÆ
Definition.—Aftershaft rudimentary. Aquincubital. Oil gland tufted.
Muscle formula, A(B)XY +. No biceps slip. Expansor secun-
dariorum present. Carotids, two. Cæca large. Skull desmo-
gnathous, holorhinal, with basipterygoid processes. Ribs without
uncinate processes.
This well-marked group of birds has only two genera at
most, which collectively contain but three species. It has
been chiefly investigated by PARKER,” GARROD,3 MITCHELL,4
and myself.5
1 In Quart. Journi. Geol. Soc. xlii. p. 366.
2. On the Systematic Position of the Crested Screamer,' P. Z. S. 1863,
p. 511.
3. On the Anatomy of Chaura derbiana,' &c., ibid. 1876, p. 189.
4. On the Anatomy of Chaura chavaria,' ibid. 1895, p. 350.
5.On some Points in the Anatomy of Chauna chavaria,' ibid. 1886, p. 178,
and BEDDARD and MITCHELL, On the Anatomy of Palainedea,' ibid. 1894,
p. 536.
GG 2
452
AND CLASSIFICATION OF BIRDS
NO
STRUCTURE 1)
The skin in these birds is excessively emphysematous,
save only on the shoulder, and-in Palamedea and Chauna
derbiana-on the tibia. The feathers, however, do not per-
forate the cutaneous air cells, but cause the skin to be
indented where they are inserted.' The aftershaft, though
present, is confined to the feathers on the nape of the neck.
The rectrices are twelve in Chauna and fourteen in Palame-
dea. The oil gland in Ch. derbiana has a single orifice on
each side; it is encircled by feathers which constitute the
tuft.
In Ch. chavaria the summit of the oil gland is covered
by feathers, a line of which separates the two orifices of the
gland. In Palamedea the same is the case, but the encircling
ring of feathers is not complete on the ventral side. The
pterylosis is almost unique in the fact that there are no
apteria, except, indeed, a space in the axillary cavities, and
these are covered with down feathers. The strong horny
spur borne on a bony core, an outgrowth of the first meta-
carpal, is comparable to a thickened featherless patch of skin
in a corresponding situation in Sarcidiornis.?
The patagialis muscle is not reinforced by a biceps slip;
the brevis tendon is single, but broad, and without a patagial
fan. The expansor secundariorum is present and ciconiine.'
The insertion of the deltoides posterior is extensive in Pala-
medeamfor about three inches down the humerus. The
anconæus has a well-marked humeral head. The division of
the biceps commences in the fleshy belly of the muscle.
In all the members of this family a very peculiar muscle
exists, to which Mr. MITCHELL and I have given the name of
costo-sternalis externus. It arises from the third, fourth,
and fifth ribs by a tendinous head, and is inserted on to the
costal edge of the sternum half an inch from the posterior
end.
The muscles of the leg are complete, as regards those
upon which GARROD laid stress in his classification, in
Chauna. In Palamedea, however, the accessory femorocau-
dal is absent. The biceps has not an anserine insertion, but
? Not, of course, to the carpal spur of Plectropterus.
153
passes through a loop in the ordinary way. Both peroneal
muscles are present; the tibialis anticus is split just at its
insertion. The deep flexor tendons differ somewhat in the
UU

PS
SP
.
Ni
.
2
NA
ES
SA
Hub
.
11.-
lllllllll
NOK
.
U11
IN
WS
ilin
IULIER
hi
!"
11:11
WS
27
UANZI/
TAS
l
UZUN
He
.
UST
W
T
:11i1i.
IIN
.
.
.
-
.
N
.
SS
11.
"1
A
VIA
11
M
1
:
.
WO
.
...
...
INN
NA
T
.
.
V
U
1
mor
llll
PS..
. . .
.
.
.
.
...
HI
.
!
NA
a
It
.
.1
ZINA
!
lun
-
NI
-
Po
-
.
-
IITA
N
ZE
WIIIIII/
INI
.
*
.
77177
-
We
-
ཆཆས
...
-
-
LE
.
.
ORKEL
e
CS
92
- Sex
.
-
ES
MO
.
-
SAN
a
.
*
L
SSSR
-T
Set
-
...
-
-
-
P
A
.
11
.
WONIN
HIRI
-se.
!!
iii..
.
.
****
:.::
.
.
.
.
.
Z
.
..
V
RUNN
A
All
*
..
...
.
WILL
.
.
.
..
.
-
.
.
- IS
.
+
+
WWW
.
..
.
.
IIIIIIIIIIIIIIII
:
...
.
.
.
.
.
M
*
.
*.
..:::*
*.
.
.
FIG. 213.-CÆCA OF Chauna chavaria (AFTER BEDDARD).
454
STRUCTURE AND CLASSIFICATION OF BIRDS
three species. In Palamedea the flexor longus hallucis is
slender, and gives off a vinculum to the flexor Communis
tendon, before supplying the first digit; in Chauna derbiana
there is no branch to the first digit at all; Chauna chavaria

ul
11
.
..
.
.
....
UC
distinct vincula..
The palate (of Ch. chavaria at any
rate) is provided with three longitudinal
rows of papillæ ; the tongue is just over
an inch long, and its base is edged with
spines. There is no transverse constric-
tion or oblique groove, such as is found
in many anatiform birds. The proven-
triculus is peculiar; there is a narrow
zone of glands round the oesophageal
aperture, from which a broad triangular
patch extends down one side of the
cavity. The gizzard is decidedly small.
The lobes of the liver are more nearly
equal in size in Chauna than in Pala-
medea ; in all there is a conspicuous gall
bladder. The cæca (fig. 213) are in
some respects unique in structure; they
are in the first place large, measuring
three inches or so in length; they are
sacculated by a single band.
FIG. 214.-WINDPIPE OF The windpipe agrees with that of
Palamedea (AFTER BED-
DARD AND MITCHELL), some of the Anseres in having two pairs
of extrinsic muscles : 1 the upper pair is
inserted into the middle of the membrane, which runs
between the coracoid and the corresponding limb of the
furcula ; the lower pair close to the costal processes of the
sternum. The intrinsic muscles cease some little way in
front of the syrinx.
The prebronchial and subbronchial air sacs are, in Ch.
chavaria at least, much divided up, as in the storks. In
TO
nema
WUNLAYN
SUNT
all
H
Apparently first noted by CRISP, : On the Visceral Anatomy of the Screamer,'
P.Z. S. 1864, p. 14.
PALAMEDEÆ
455
V
WWF
AG
-
.
AN
II
.
SEZO
L
-
*
III
.
V
.
A
E
R
*
)
.
.
IN
TÄ
.
%
16.
**
.
ie
2
.
.
4
II.
1
.
.
Chauna the lower pair of extrinsic muscles fan out upon the
aponeurosis of the lungs.
There are eighteen cervical vertebræ in Palamedea and in
Ch. chavaria, nineteen in Ch. derbiana. There are seven
complete ribs in Palamedea, eight in Chauna. The sternum,
which has one notch on either side, has neither external nor
internal spina. There are in neither genus any traces of
uncinate processes on the ribs, a
character which is unique among
living birds.
The skull of the Palamedeidæ
has many anserine characteristics,
which have been emphasised by
PARKER, and perhaps rather too
lightly touched upon by GARROD.
In their desmognathism (which is
a complete fusion) they are, of
course, anserine, the form of the
maxillo-palatines most recalling
those of Mergus. The form of the
palatines is duck-like or gallina-
ceous in the rudimentary character
of the internal lamina, which is a
mere ridge. The pterygoids are
articulated to the large oval duck-
like basipterygoid processes, nearer
to their middle than is the case
with the Anseres. The lacrymals FIG. 215.-SKULL or Chauna
derbianc. VENTRAL ASPECT.
are small, quite contrary to what (AFTER GARROD.)
is found among the Anseres,
though the ectethmoids are not unlike those of the
latter group. The anterior part of the face, with the clear-
-cut holorhinal nostrils and the hooked bill, is suggestive of
Cariana or a gallinaceous bird ; it does not at least recall the
duck or goose. The interorbital septum is deficient in front,

1..
Y
.
.
wi
.
.
SUNCE
A
Hot
EN
24
Bu
li>
ITUNES
LI
VOX
VO
SUS
SAS
.
.
AT
.
CU
10
TO
*
.
.
ca
11
.
CI
.
22
UU
PAK
::-1111111!.
A
!!!".;
E
.
It
Willa
.
e
17
za
.
.
.
TriNKY
HOIXIT:
imo
i Not even a rudiment of these characteristically avian structures has, so far
as I am aware, been detected.
456
STRUCTURE AND CLASSIFICATION OF BIRDS
but not fenestrate posteriorly. Occipital fontanelles are
absent. :
Though perhaps rightly placed in the neighbourhood of
the geese, it is obvious, from what has been said, that the
Palamedeidæ are distinguished from them by many differ-
ences, of which the most important are perhaps-
(1) Continuous feathering.
(2) Absence of biceps slip to patagium.
(3) Peculiar form of intestinal cæca.
(4) Normal character of biceps cruris.
(5) Emphysematous character of skin and breaking up of
cervical air sacs.
On the other hand there is nothing in the skull which
forbids an association with the Anseres, and the windpipe,
with its two pairs of extrinsic muscles, is decidedly goose-like.
But it must be remembered that this feature is also found
among Galli, and in a few other forms.
ANSERES 1
Definition.—Oil gland tufted. Aftershaft small or absent. Aquin-
cubital. Two carotids. Trachea with two pairs of extrinsic
muscles. Cæca long. Gall bladder present. Biceps slip present.
Gluteus maximus large. Muscle formula of leg, ABX +. Skull
desmognathous, with basipterygoid facets.
The swans, geese, ducks, and mergansers, which make up
this large assemblage of birds, are all aquatic, or semi-aquatic,
in habit, and in correspondence have webbed feet, with the
exception only of Anseranas. They are also for the most
part strong flyers, excepting only the living Tachyeres cinereus
and the extinct Cremiornis calcitrans.
Tachyeres cinereus, the 'steamer duck,' from the shores
of Patagonia, has been investigated by R. O. CUNNINGHAM.2
It does not appear from his memoir, which relates chiefly
to osteology, but in the course of which he describes and
1 H. SCEBOHM, “An Attempt to diagnose the Sub-Orders of the Ancient
Ardeo-Anserine Assemblage,' &c., Ibis, 1889, p. 92.
2 "On the Steamer Duck,' Tr. 2. S. vii. p. 493.
ANSERES
457
figures the gizzard and windpipe, that there are noteworthy
modifications of structure. The bird flies strongly when
young, but swims only when adult. CUNNINGHAM suggests
a greater density of the bones; but when weighed and com-
pared with the skeleton of some other Anseres no reliable
differences were apparent.
Cremiornis calcitrans is a large anserine bird from the
Pleistocene deposits of New Zealand, which, according to
Sir JAMES HECTOR, stood over two feet high, and was at
least three feet in length. Cremiornis is characterised by
the great weight of its bones ; the following comparative
table from HECTOR'S paper brings out this fact:-
C

Bulk
Weight
WOT PLS
.
Non-volant
Cnemiornis
Ocydroinus
Stringops
Nestor .
Hieracidea
10
10
10
10
244
210
187
131
126
Volant
10
It seems clear from these comparisons that Cnemiornis
could not have been a flying bird. Moreover the sternum
has a keel whose highest elevation is under three lines.
This bone appears to have possessed no lateral notches, but
only a slight median concavity. On the other hand the
'rough tubercular surface of the keel is perhaps a little
suggestive of a missing cartilaginous piece.
The suggestion of FÜRBRINGER to separate Cnemiornis
into a sub-family, Cnemiornithinæ, seems perhaps, in the
light of the above facts, to be justifiable. But the remainder
of the members of the family cannot be divided with precision.
It is above all impossible to divide swans, geese, and ducks
from each other into three such groups. Nevertheless, as
will be gathered from the following account of their struc-
ture, the Anseres vary very much among themselves—more
especially in the structure of the windpipe.
All the Anseres, as noted in the definition, have a tufted
oil gland.
1. On Creiornis calcitrairs,' &c., P. 2. S. 1873, p. 768, and 1874, p. 307.
458
STRUCTURE AND CLASSIFICATION OF BIRDS
4
.
"
...
1
.
.
1
.
32
."
..
Dr
Stih
.
41
.
.
.
4
S
.
.
.
The aftershaft is always small, and sometimes absent.
In the pterylosis (according to NITZSCH) the pectoral tract
divides about halfway down the
neck ; it is broad, and gives off on
each side a stronger outer band.
The dorsal tract also divides
about halfway down the neck, and
encloses a long narrow space.
The number of rectrices in
various genera is shown in the
annexed table.

.
**
-
.
.-
.
4
".
-
.
--
261
-
.
.
-
I
.
.
*
1
22
ISH-
"
LA
Ft
RE
.
..
-
...
22
34
"
*
NS2
*
•
BISS395
-
SL
:
.
!
.
-
...
*
OS
C.
.
SOLARE
*
T
.
.
*.*
.
.
!
--
:
.
.
..
.
OS
.
.
14.
Rectrices
XY
.
·
*
1
The
ra
ESG:
.
.
R
.
..
*
co
Y
W
VERINA
.
..
ZEE
WA2
.
Biziura lobata
Anas specularis . .
Anas boschas . . .
Aix sponsa . . .
Erismatura rubida . .
Cereopsis Novce Hollandice
Plectropterus gambersis .
Cygnus mmusicus . .
Fuligula rufina. . .
Dafila acuta . . .
Bernicla canadensis .
Mergus nerganser . .
albicillus . .
OR
. 24
. . 14
. . 14
. . 16
. . 18
141
. . 16
. . 24
16
16
... 18
. . 18
. .
+
ANAS
-
-
--
-
-
-
.
X
--
-
-
ve
.
.
SSS
T.
..
:
TAM
RA
HO
-1
VY..
CSS
.
.
..
.
A
S.
STAN
II
.
16
• 1126
.
X
.
AL
Y
.
.
2
"
XIVACY
SE11
linguæ.
The tongue is strong and
bordered with spines. In Mergus
FIG. 216.--MOUTH of only is it thin and pointed.
Biziura lobata (AFTER The liver has a large gall
FORBES).
P, pouch ; 1, tongue ; f.1, frænum bladder.
Biziura lobata is unique among
Anseres ? in having a subgular pouch (fig. 216), formed by a
duplicature of the frænum linguæ.
The most noteworthy point that appears from the facts
given on the next page is the gradual reduction of the cæca
in the mergansers and smews, and the great range of variation
in size which they exhibit in Cygnus nigricollis, a variation
NI
ITU
NITZSCH says 16.
2 Cf. Otides for a similar structure.
ANSERES
459
which does not, it will be observed, bear any relation to the
variation of the total length of the intestine.
The following are some intestinal measurements :-
S. I.
L. I.
Cæc.
Iuches
2.25
.
.
Ft. In.
5 4
4 8
4 3
8 6.5
6 11.25
5 2:5
Inches
1.25, 1.5
1.8
21
6.75
7.75
.
.
4.5
6.5
2:75
.
.
3.5
.
4
4
1.2
7
.
.
-
-
.
-
2.2, 1.75
5
2.75, 3
3.25
9
2.5, 2.75
3.75,4
15
-
-
.
-
3-5
-
.
-
-
2.5
.
ODA
11 4
9 6
3 6
4 10.5
2:25
.
9, 10
3.2, 3.4
3.5
5.5, 6
6.75, 7.25
er DDLA HA CON
3
.
9
1
Mergus 11erganser .
, castor . .
, albicillus . .
Biziura lobata . .
Anas specularis .
Rhodonessa caryophyllacea
Aix sponsa i
Sarcidiornis inelanota mo .
, carunculata
Bernicla canadensis .
jubata ð . .
Chenalopex jubata .. ..
Cygnus nigricollis. .
Dendrocygna autumnalis . ..
Metopiana peposaca . .
Plectropterus gambensis .
us niger ő .
Cereopsis Nove Hollandice
Anser albifrons . .
Chloephaga magellanica 4
Cygnus olor . .
ferus &
,, baccc11coton 3
, atratus . .
Tadoriza tadornoides .
Dafila acuta...
Pæcilonetta bahamensis 8
bahanensis ģ
Querquedula circia .
Hymenolæmus malacorhynchus
Spatula clypeata . .
Fuligula ferina . .
„ rufina . .
Nyroca leucophthalma .
.
no cowo
.
.
:
indicus ?
:
.
ci
11.5
7.75
5.5
12, 13
14, 15
9.25
+
.
.
.
9
m
.
.
.
ä
7.5
11 :
3.5, 4.5
4, 4.5
4, 4.25
3, 3.3
3.
3.8, 4.25
.
.
to
oo ! * * * * * *
3.5, 3.75
4.5
6.75
6.5, 7.5
1.5
tam
Only one present.
The muscular anatony of the Anseres is very uniform,
which coincides with their uniformity of life habit. Even
presumed aberrant types, such as Mergus, Biziura, and
IX
460
STRUCTURE AND CLASSIFICATION OF BIRDS
Tachyeres, are hardly if at all to be distinguished anatomically
from the typical geese and ducks. Our knowledge of the
muscular structure of this group of birds is mainly due to
FÜRBRINGER, who has illustrated the fore half of the body
by two double plates referring to Anser cinereus.
An interesting duck character (also, however, found in
Colymbus, Tinami, and some Galli) is the meeting of the two
great pectoral muscles over the carina sterni. In Mergus

ht
th
Bi
.
.
www.
..
RUTINITIVE
11
INIO
CI
.
.
LA
..
home
w
ERA
m
C
SA
.
.
re
.
.
.
www.
...
..
.
.
..
.
I.
7
COLO
..
.
.
.
.
.
FIG. 217.–BICEPS FEMORIS OF DUCK (Bi), TO SHOW ITS
RELATIONS TO GASTROCNEMIUS (AFTER WELDON).
merganser, for example, they blend for a space of half
an inch.
There is a biceps slip present, and this has at least
sometimes a peculiar arrangement, which is remarkably like
that of the Colymbi. In Anser cinereus FÜRBRINGER
figures the biceps slip as attached in the ordinary way to
the tendon of the tensor patagii longus; but before it is thus
attached it gives off a slender tendon, which exactly as in
the Colymbi-runs over the patagium'and is inserted on to
the fore arm in front of the broad and diffuse tensor, patagii
brevis tendon.
In Anas FÜRBRINGER figures this tendon as joining the
| Not in Cygnus Bewicki.
ANSERES
461
patagial fan, a state of affairs which is exactly paralleled in
Æchmophorus (see p. 387). In ducks there is a peculiarity in
the biceps to which attention appears to have been first
called by FÜRBRINGER. There is a tendinous sheath
partly covering the patagial side of the muscle and derived

Iwona
Wb
U
V
WWW
WUR
U AMIGA

1
SI

TS
Witte
2
WHIKALI
Nic
-
-
B
-
2
2
.-
.*
E
-
LDP
..
UT
A
S
"
*
*
.
1
lit
.10.11
TAPI
ARA
PL
1
.
9
.
..
.
WEEN
.
..!
NY
!
11
I!
11
...
VERIG
>
VANSA
F
!
X V IENU! 11
Panny
PODEM
YAX
il
EV
.
.
U.
:
.
MAUMI
Wu.
LY
.
BUENO
2
to the
../
llam
Miam. inth
ASSERE
RESH
-,
Vagandi
*
bol
11
PUS
un toy
US
OM
..
.
H
Eu
17
.
oll
TUS
.
KA
BE
.
"
NI
.
.
.
WY
/"
a
:
.
2.
CR
H
:
ENKI
..
B
NAMIS
.
TODO
2.
"
41
S
..
P
*
*
130 AUSNA
Tips!
SAN
SETT
ry
515
ANK
SU
A
16
;
.)
Hogy
1.)
Wat
18
mler
Fig. 218.—WINDPIPE OF
Sarcidiornis melanota ở
(AFTER GARROD)
FIG. 219.-SAME OF
S. melanota
(AFTER GARROD).
FIG. 220.-SAME OF
Rhodonessa caryo-
phyllacea (AFTER
GARROD).
from the pectoralis primus. A similar structure occurs in
Colymbi and storks, and in Casuarius its homologue is more
independent of the biceps. The latter at any rate, if not
the former, seems to me to correspond to a peculiar muscle
found in the tinamous (cf. p. 489).
The expansor secundariorum shows some variations. In
Biziura lobata it is entirely absent. In Aix sponsa the
tendons thin off and are lost on the interthoracic septa. In
others, as, for instance, Bernicla canadensis, the expanded
tendons end upon the oesophagus; on the way thither they
462
STRUCTURE AND CLASSIFICATION OF BIRDS
blend with the sheath of the carotids, which when pulled
upon they compress, as also the jugulars. This may con-
ceivably be a provision for increasing the blood supply of the
wings by interrupting that of the head. Finally in Cygnus,
Mergus, and Sarcidiornis the expansor secundariorum is
ciconiiform.
The deltoid has a strong scapular slip. The anconaus
u


RI
ALL
201
2
TV
SN
"
*
*
WA
40
*
**
INN
.
*
23.
S
.
Y
A
*
*
MV
ill:
.
DY
si
V
W
ITHIUD
CS1
Wh
7
B
ROL
.
SR
fo.
AT
2
Ru
A
Tirn
N
.
La
Etware
TOWO
VITRO
UTWA
4
h
tea
LAMAN
Lorem
masinate
WMO
CS
.
Fig. 221.-SYRINX OF R. caryophyllacea S. RIGHT-HAND FIG., FRONT
VIEW; LEFT-HAND, SIDE VIEW. (AFTER GARROD.):
has a humeral slip. In the hind limb all Anseres have the
formula ABX+. The femorocaudal is slender, the acces-
sory very large. In Biziura: lobata the ambiens has a pecu-
liarity found also in Phalacrocorax and the extinct Hesper-
ornis—that its tendon perforates the patella. The gluteus
maximus is very large, and its origin descends below the aceta-
bulum. A marked peculiarity of the Anseres, found else-
where in Struthio, is that the biceps femoris gives off a slip
to the gastrocnemius. In most Anseres the flexor longus
hallucis gives off a slip to the hallux before fusing with the
Iul
ANSERES
463

1.
12
XY
.
-
14.2
HINS
i
YS
LE
OV
.
NET
*
...
a
.
.
"
.
*
W
Air
.
IP
.
6
*
*
.
*
1
1
..
N
?
--
14
-
-
J
.
.
..
!
-
C
ICA
+ TUIN.
V
H
-
1.310
.
.,
.
.'
.
.
2
'
UM
WE
FIES
.
.
-
TRE
..
!
RI
.
*
01.
YA
!
MA
MINO
.
UR
AT&T
2
.
.
NA
V
ta
:
.
.
-
ESTE
-
...
14
flexor profundus ; in Biziura lobata
the same slip is given off, but it be-
comes lost on one of the annular masses
of fibrocartilage surrounding the other
flexors.
The windpipe in the Anseres is nearly
always straight, the only exception
among the ducks and geese as yet
recorded being Anseranas melanoleuca,
in the males of which the trachea forms
a double loop, extending to quite the
end of the pectoral muscles. A
second peculiarity of the trachea is
seen in the males of Metopiana pepo-
saca, Strictonetta novosa,' Melanitta
fusca, Nyroca, Mergus, Somateria, and
Clangula. In these (see fig. 222) there
is a bulbous enlargement of the trachea
some little way in front of the syrinx.
It is present, but very slightly developed,
in Fuligula rufina. In nearly all the
ducks the syrinx in the male has a re-
markable asymmetrical enlargement,
which is as a rule entirely bony, but is
sometimes (Mergus, Clangula, Nyroca,
Fuligula) mainly formed of menbrane.
The accompanying figures will give
some idea of the form of this structure,
which shows differences in different
species. The figures are taken from
a memoir upon the subject by Professor
GARROD.2 YARRELL 3 and EYTON 4 have
121 RSD
:
.:
NE
ESS
131
EMIL
LUU
.
1
KAU15
mind
.
Var
.
30
.
11111
.
12
HO
SA
2
.
Wi-
"
-
11
L21
t
.*
F
23
T .
RI
.
19:
11NR NUAXH):
!
SAR.
WON
KI
* *
*
.
AS1163
I E. P. RAMSAY, 'Note on the Tracheæ of certain
Australian Ducks' Proc. Linn. Soc. N. S. W. iii.
1879, p. 154.
? On the Form of the Lower Larynx in certain
Species of Ducks' P. 2. S. 1875, p. 151.
3 British Birds.
4 Monograph of the Anatida or Duck Tribe.
FANART
TLT
Fig. 222.-WINDPIPE OF
· Metopiana peposaca o
(AFTER GARROD).
464
STRUCTURE AND CLASSIFICATION OF BIRDS
IVUNIA
Marian
Or
SIMO
.
WS
*
*
also figured a good many of the syringes of the ducks in
illustration of this matter. The only ducks in which there is
certainly no modification of the syrinx of this kind are
Biziura lobata, Edemia nigra, and Melanitta fusca ; in the
former bird FORBES 1 has described a plain syrinx (fig. 223)
with a box at the bifurcation of the bronchi formed of the
last tracheal and of a few of the anterior bronchial semi-rings.
He suspects, however, that the
genus Erismatura 2 will be found
to have a similar syrinx minus a
lateral outgrowth, as MACGILLI-
VRAY appears to have described
something of the kind. Somateria
mollissima has a very slight sym-
metrical enlargement of the syrinx.
A very marked characteristic of the
Anseres is the possession of two
Fig. 223.—SYRINX OF Biziura 8 pairs of extrinsic tracheal muscles.
(AFTER FORBES).
In this they agree with Pala-
medeidæ. The single pair of intrinsic muscles are as a rule
attached to the third or fourth tracheal ring in front of
the syrinx in the ducks.
Among the Cygnina (swans) there is frequently a looped
trachea, the coils being intrasternal. This is so with both
sexes of C. ferus, C. buccinator, C. americanus, and C.
Bewicki ; there appears to be a trace of the looping in C.
atratus. In C. olor, C. immutabilis, C. nigricollis, and C.
coscoroba the windpipe is straight in both sexes. It is
interesting to note that in C. buccinator, at any rate, the
intrinsic muscles do not follow the coils that bridge across
the loop. This species of swan is also remarkable for the
extraordinary dilatation of the middle of each bronchus, which
is, again, characteristic of both sexes. These dilatations would
be almost spherical were it not for the irregular crumpling

T'A Note on some points in the Anatomy of an Australian Duck (Biziurce
lobata),' P. 2. S. 1882, p. 455.
2 • There is no expansion or tympanum, as in other ducks' (Orn. Biogr. iv.
1838, p. 331).
ANSERES
465
1
1
here and there; their diameter is about an inch. The
bronchial rings which cover them have largely lost their
individuality, and form an irregular network of partly
cartilaginous and partly osseous bars.
The males (? as to females) of Cygnus ferus and C.
Bewicki at any rate show less marked traces of the same
peculiarity.
In the former there is a distinct fusiform dilatation, but
further down the bronchi than in C. buccinator, between
the rings of which there is some slight formation of
anastomoses. In C. Bewicki both features are still less
marked.
Cygnus olor, C. atratus, C. nigricollis, and C. coscoroba
have no trace of this remarkable structure. I have examined
males of all and females of two.
As to the geese, Bernicla canadensis, Anser indicus, and
Cereopsis Nove Hollandice (and doubtless many others) have
a syrinx without the anatine bulbus. It is present in
Plectropterus (gambensis, Ruppeli, niger) and Sarcidiornis,
and present, though small and solid, in Chenalopex jubata.
It is fenestrated in Plectropterus, not so in Sarcidiornis.
Dendrocygna appears to illustrate the commencement of
the syringeal enlargement. In the male of D. arcuata the
last twelve tracheal rings are widened and enclose a spacious
chamber about twice the diameter of the rest of the trachea.
The intrinsic muscles are attached to the beginning of this
thin-walled box. In the female there is an indication of
this in the fact that eleven of the tracheal rings in front of
the last three are imperfect posteriorly, being closed by
membrane. The intrinsic muscles also are attached opposite
to the commencement of this modified region of the trachea.
In D. autumnalis there is the same box, which is
strengthened posteriorly by a strong bony bar. The wind-
pipe of the female has no such modification as has been
described above in D. arcuata.
It is possible that this single enlargement in Dendrocygna
is the beginning of both the tracheal swelling and the
syringeal bulbus in Mergus, &c.
1
Η
Η
466
STRUCTURE AND CLASSIFICATION OF BIRDS
The number of cervical vertebre l among the Anseres varies
considerably. The smallest number is found, for example,
in Plectropterus gambensis, Biziura lobata, and Tachyeres
cinereus, where there are only sixteen. In Edemia nigra
there are seventeen; among the swans, twenty to twenty-
four. The number of true ribs also varies considerably.
The smallest number is to be seen in Cereopsis, where there
are but five. Tachyeres, Plectropterus, and a number of
other genera have seven; there are eight in Tadorna vulp-
anser, and as many as nine in certain swans and geese..
The sternum, which has a moderate spina externa, but
no spina interna, is whole in Cneniornis, but has two
notches or foramina in other Anseres. The coracoids come
into contact, but do not overlap at their sternal articulation.
The procoracoid is small, and does not reach the clavicle,
which, however, reaches the scapula.
The skull has large oval sessile basipterygoid processes.
It is holorhinal and desmognathous. There are frequently
lateral occipital fontanelles, as in many 'pluvialine' birds.2
The palatines are remarkable for the rudimentary character
of their inner laminæ, which brings about a resemblance to
the gallinaceous birds, as has been pointed out by HUXLEY,
and, it may be added, to the parrots. That part of the
palatine is only indicated by a not well marked ridge which
is totally absent in Bernicla leucopsis, Chen cærulescens.
The general direction of the bone, therefore, is oblique ; it is
only near to the attachment with the pterygoids that it
becomes feathered out in a horizontal direction. That, at
least, is the more normal arrangement; for in Mergus the
greater part of the bone has its upper and lower surface co-
incident with the horizontal axis. This, too, is the case with
Biziura lobata.
The oval basipterygoid facets for articulation with the
2
| For osteology see PARKER, 'On the Morphology of the Duck and the Auk
Tribes,' Currninghanı Memoirs R. Irish Ac. No. 6,1890, and SHUFELDT, 'On N.
American Anseres,' P. U. S. Nat. Mus. xi. p. 215.
2 Absent in Cereopsis, Biziura, Cygnus, and Cnemiornis. See Owex, Tr. 2.
S. ix. pt iii.
ANSERES
467
pterygoids are placed so far forwards that the anterior ends
of those bones articulate with them.

14
.
.
.
.
DEAD
Site
A
TA!!
.
Wil
11.11
MEPIC/
WIRIN
EUR
M
I
1.
T:
2
.
V.VN
1
MY
ni
Bull
AX
S
iin
.
ORAN
:
NON
A
IR
UN
+
1
.
VOX
ST
mit
NA
ma
Pmx
WA
.
.
10
SO
FIG. 224.-SKULL or Querquedula crecca. · LATERAL VIEW.
(AFTER HUXLEY.)
Fr, frontal ; Na, pasal ; Pm.x, premaxilla ; Vo, vomer ; Pa, palatine ; Pt, pterygoid. .
in
ER
Pinel
C
.
+
--
-
-
..
.
21
LILU
..
-
MIT
19K
T
:
BE
SER
.
.
R2
The vomer is a thin deepish plate of bone which is more
or less intimately connected with the
inedian septum and maxillo-palatines in
front. The maxillo-palatines are com-
pletely fused across the middle line in
many Anseres (e.g. Chen, Hymenolamus);
in Biziura and Mergus they come into
contact but are not fused. The latter
has very un-ducklike palatine in that the
somewhat delicate maxillo-palatines diverge
from each other after their junction pos-
teriorly as well as anteriorly, the palatine
vacuity in front being (for a duck) un-
usually extensive. In Chen cærulescens,
indeed, secondary bony growths have
almost completely obliterated this vacuity,
a kind of 'false' palate having been
formed.
The lacrymal bones are large, having
a considerable length of line of union with
FIG. 225.- VENTRAL
the skull; they are sometimes (e.g. Chloë-
VIEW OF SAME.
phaga) and sometimes not (e.g. Mergus) Map, maxillo-palatines.
ankylosed with the orbital margin. Cere-
opsis has (among the genera which I have examined) a skull

....
...
9
.
.
..
.
..
OS
met
11
SMK
Other letters as in fig. 224.
I H 2
468
STRUCTURE AND CLASSIFICATION OF BIRDS
which is peculiar in that posteriorly the lacrymal is free
from the orbital wall, but is fused with a process of the
frontal at the anterior end of the supra-orbital impression,
leaving (as in Chionis and some other birds) a foramen.' In
Cereopsis the descending process of the lacrymal curves back-
wards and comes near to the zygoma ; 2 the junction is
completely effected, and there is ankylosis, in Dendrocygna.
The ectethmoids of the Anseres are often largely deficient
as ossifications; when present they are thin-walled bubble-
like structures, coming into relation with the lacrymals.
The interorbital septum is generally very complete ; but it
is largely vacuolate in Mergus and Biziura.
The following table shows the number of cervical
vertebræ and the condition of the hamapophyses and
catapophyses in a series of anserine birds :-

C. V.
Hyp.
Cat, nearly
unite
Posterior
Catapoph.
16
17
Plectropterus gambensis .
Metopiana peposaca.
Sarcidiornis carunculata .
Hymenolamus.
Tachyeres cinereus .
dernia nigra. ..
Biziura lobata
Dendrocygna autumnalis .
Bernicla brenta . .
ooooo
C13-03
C14-15
C13-14
C13-14
C13-15
C12-15
C13-D5
C13-D3
C15-D4
C12, 13
C12, 13
C11, 12
c11, 12
C11, 121
C10, 11
C11, 12
C11, 12
C12–14
C16-D1
C17-D3
C15-D2
C15-D2
C15-D3
C15-D3
C15-D3
C16-D1
C18, 19 2
19
· Fused to form a solid bifid 'hæmapophysis, as in some other birds.
2 They are rudimentary and do not mount upon the hypapophysis.
As a possible appendix to the Anseres must be mentioned
three or four species of an extinct genus of birds, Gastornis,
flightless and larger than an ostrich. It has been found
only in Europe and from Eocene beds. It is placed among
the 'ratites’ by LYDEKKER and some others; this is largely
on account of the coracoid, which is imperfect above, and
appeared to LEMOINE and others as probably platycora-
coidal.' FÜRBRINGER, however, considers that the tuberosity
1 This is figured by Owen in his paper on Cremiornis, Tr. Z. S. ix. pl. 35,
fig. 8.
2 Sometimes joining. Cf. OWEN, loc. cit. pl. 35, fig. 6.
ANSERES
469
described by the latter as 'tubérosité préglénoïdienne'is
really the broken end of the scapula, which would be thus,
as in Didus, ankylosed with the coracoid, and would also
form with it an angle approaching to a right angle. The
supposed remains of the scapula, on the other hand, are for
FÜRBRINGER the acrocoracoid. On this interpretation the
shoulder girdle of Gastornis would be a nearly typical
carinate shoulder girdle. The length and slenderness
of the coracoid too is not a ratite character, but it does
ally Gastorovis with Cremiornis (and also for that matter
with Phororhacos). In spite of the freedom of the meta-
carpals (a character only known elsewhere in Archæo-
pteryx), the complete furcula and various points in the bones
of the lower limb, pointed out by NEWTON, together with
the facts already referred to, seem to point to a greater like-
ness to Cnemiornis than to any other known type. The
skull had basipterygoid processes and seemingly teeth in
sockets. The pygostyle appears to have been at most very
small and probably absent.
I
1
/
ICHTHYORNITIES
Definition.-Small toothed birds with carinate shoulder girdle and
sternum. Bones of pelvis not united. Quadrate single-headed.
Vertebræ amphicoelous.
This group of birds, from the Cretaceous of North
America, has been investigated by MARSH, who, in his great
work upon the toothed birds, placed it in a group Odonto-
tormæ, as opposed to Odontolcæ (Hesperornis), on account of
the fact that the teeth are implanted each in a distinct
socket. Its relationship to other groups is doubtful; but it
is probably not greatly misplaced if we consider it in the
neighbourhood of the stork and plover tribe, as has been done
by FÜRBRINGER. The group contains two genera—Ichthy-
ornis and Apatoris. Of the former MARSH refers to several
species, viz. I. dispar, I. victor, I. validus, I. tener, I. agilis,
and I. anceps.
Of Apatornis there is but one species known, A. celer.
470
STRUCTURE AND CLASSIFICATION OF BIRDS
These two genera comprise a number of “small birds,
scarcely larger than a pigeon. In their powerful wings and
small legs and feet they remind one of the terns, and accord-
ing to present evidence they were aquatic birds of similar
life and habits.'
The restoration of Ichthyornis given by MARSH has
been extensively copied in various works, in some of which
it would appear as if our knowledge of the osteology.of the
species selected were greater than is really the case. It has
been made, for example, to show schizorhinal nostrils and a
pelvis constructed after the carinate type, with the ischia and
ilia fused. It is not known whether the skull was schizo-
rhinal, as only the calvarium and the lower jaw and a
fragment of the upper jaw have been discovered. The skull
has well-marked grooves for the supra-orbital glands ; the
quadrate, as stated in the definition, is single-headed, as in
Hesperornis and many Struthiones. The brain, like that of
Hesperornis, is small, and the cerebellum is remarkably
large as compared with the hemispheres. The teeth of Ichthy-
01nis are implanted in distinct sockets.
MARSH has remarked upon the close resemblance between
the lower jaw, with its teeth, and that of the smaller mosa-
sauroid reptiles. In Ichthyornis dispar there are twenty-
one distinct sockets in each ramus of the jaw. I. victor had
the same number of teeth ; in I. anceps the teeth were more
numerous, and at the same time more slender. The jaws.
were united, as in Hesperornis, by cartilage or ligament..
The vertebræ, as already mentioned, are amphiccelous ;
but an approach to the typical saddle-shaped vertebræ is
seen in some of them. The atlas is notched for the odontoid
process of the axis. None of the dorsal vertebræ appear to
have coalesced, and there is a pygostyle quite typical in form, .
but rather small. The shoulder girdle of both Ichthyornis
and Apatornis is constructed upon the carinate plan. There
is the same angle between the scapula and the coracoid, and
the clavicles are well developed. There are, however, differ-
I SAUFELDT (* Notes on the Extinct Bird Ichthyornis,' J. Anat. Phys. xxvii.
p. 336) especially compares Ichthyornis with Rhynchops and Sterna.
ICHTHYORNITHES
471
ences in detail. In Apatornis there is a very long acromial
process. The coracoids overlap at their articulation with the
sternum, more so in Ichthyornis than in Apatornis. The
clavicles are generally figured as typically carinate ; but the
only part of this bone known is a fragment from the upper
end of that bone in Apatornis.' The sternum is deeply
keeled.
The bones of the fore limb are well developed ; the
humerus has a very large crest, surpassing in comparative
size that of any recent bird ; this clearly indicates a powerful
flyer, and the rest of the bones of the limb bear out this view.
Though nothing is known of the structure of the feathers,
there are upon the ulna impressions for the quill feathers.
In the pelvis all the bones are free posteriorly, as in Hes-
perornis, Apteryx, &c. The acetabulum is perforate, as in
most recent birds ; but the perforation is of moderate size, as
in the tinamous.
In the neighbourhood of Ichthyornis are possibly to be
placed MARSH's genera Baptoriis, Telmatornis, and SEELEY'S
Enaliornis. These birds, however, Cretaceous, like Hesper-
ornis and Ichthyornis, are known by such limited material
that their position is absolutely uncertain.
The affinities of Ichthyornis to Hesperornis have been
dwelt upon by some ; but it appears that LYDEKKER'S
remark, that 'the Odontornithes are a series of birds ances-
tral to the modern series of toothless carinates,' expresses the
truth. He has furthermore added that this series differs
from the Euornithes (STEJNEGER'S name for carinates) by the
absence of union between the rami of the mandible and
between the distal ends of the ischium and ilium,' likenesses
which do not mean a near relationship, but express the
degree of development of bird structure at that period.
2
472
STRUCTURE AND CLASSIFICATION OF BIRDS
ACCIPITRES
Definition.— Aquincubital. Oil gland present. Two carotids. Skull
desmognathous and holorhinal. Cæca rudimentary or absent.
Ambiens present. Biceps slip absent.
This large group of birds admits of but a scanty defini-
tion, if we are to include in it, as is here done, the secretary
bird and the American vultures; for it then shows a con-
siderable amount of structural variation. The oil gland,

.
Av sodelovali
Anić
:
FIG. 226.—TENSORES PATAGII OF Polyboroides (AFTER BEDDARD).
l.p.l, tensor patagii longus; 1.p.br, tensor brevis; anc, anconæus ; D, deltoid.
invariably present, is generally feathered, but nude in the
Cathartidæ. In Serpentarius this gland varies in size; in
one specimen it was found to be very small and to have a
very minute tuft.
The aftershaft is absentin the Cathartida and in Pandion,
present in other Accipitres. Twelve rectrices is the usual
ACCIPITRES
473
number, but fourteen occur in Neophron percnopterus and
Rhinogryphus californianus.
There are powder-down patches in Elanus, Circus, and
Gypaetus. The pterylosis is described for a variety of types
by NITZSCH.
The ventral tract broadens out on the breast, where
it is even sometimes (Gyps fulvus) divided into an outer
and inner branch. The dorsal tract forks upon the
shoulders ; in Gypaetus barbatus each limb of the fork is
connected by a single row of feathers with the long single
median posterior portion of the tract.
In Pernis apivorus these latter slender forks are figured as
being much longer, and in Falco peregrinus they dilate into
four or five rows of feathers before uniting. In Falco
brachypterus there is the usual dorsal fork, but between its
extremities lies the beginning of the very broad posterior
part of the tract. In all these birds there are lateral neck
spaces. The lumbar tract is but little marked, or is entirely
deficient. A large amount of detail is given in NITZSCH'S
account of this family, which is treated more fully than many
others.
The tensor patagii brevis is simple in all accipitrines, and
there is never a biceps slip. There is, however, a certain
amount of variation in the tendon. The simplest form of
the tendon is seen in
Vultur monachus
Falco melanogenys
, auricularis
u subbuteo
Gyps fulvus
asalon
Tinnunculus alaudarius Thrasaetus harpyia
Microhierax coerulescens
21
where it is a simple tendon without branches, as in many
picarian birds. On the other hand in
Buteo vulgaris
Spilornis bacha
Circus maurus
cheela
, Gouldi
Neophron percnopterus
Helotarsus ecaudatus Milvago chima-chima
474
STRUCTURE AND CLASSIFICATION OF BIRDS
S
VU
Milvago chimango
Melierax polyzonus.
Gypaetus barbatus
Polyborus brasiliensis
Dryotriorchis spectabilis Polyboroides typicus
Aquila imperialis
Haliaetus albicilla
Lophoaetus occipitalis Milvus ictinus
Melierax monogrammicus Astur approximans
a wristward branch (as shown in fig. 226) is given off, the
tendon, in fact, bifurcating. FÜRBRINGER, however, while
figuring the two types, distinguishes in the apparently single
tendon of Tinnunculus two separate tendons in close contact
for their entire length.
A further complication is seen in Gypaetus and Gypo-
hierax,' where a small recurrent tendon (patagial fan) joins
the anterior branch of the brevis with the longus, a state of
affairs found to characterise Serpentarius, as will be pointed
out later.
The expansor secundariorum. 2 is present in Milvago chi-
mango, Harpyhaliaetus coronatus, Falco, Polyborus, Tinnun-
culus, and Microhierax coerulescens ; in others it is absent.
The anconaus arises in Polyboroides and in some other
types by a single head from the scapula, which is partly
fleshy and partly tendinous. In Vultur auricularis, on the
other hand, the muscle arises by two completely tendinous
heads, so that the muscle has not that value in the classi-
fication of the Accipitres that I at one time thought.3 In all
In Geranoaetus melanoleucus, which has, as have all the last-mentioned
genera, a bifurcate tendon of the brevis, a small muscular belly ending in a
tendon which becomes lost upon the patagium arose on the right side, in a
specimen which I dissected, from the extensor muscle near to the end of the
anterior branch of the brevis tendon. I am uncertain of the exact homology of
this structure in Geranoaetus.
? For muscular anatomy, &c., of Accipitres see GIEBEL, 'Bemerkungen über
Cathartes (0217C, &c., Zeitschr. f. d. ges. Naturw. ix. (1857), p. 426 ; Zur
Anatomie von Vultur fulvus,' ibid. xxi. (1863), p. 131 ; 'Zur Anatomie des
Lämmergeiers,' ibid. xxviii. (1866), p. 149 ; S. HAUGHTON, . On the Comparative
Myology of certain Birds, P. R. Irish Ac. ix. (1867), p. 524 (crane and goose
as well as hawks). He deals with weight only. E. NEANDER, Undersökningar
af Muskulaturen hos slägtet Buteo, Lund, 1875 ; MILNE-EDWARDS in Recherches
Anatomiques, clc., des Oiseaux Fossiles de la France, Paris, 1867.
3. On certain Points in the Anatomy of the Accipitres,' P. 2. S. 1889,
1
.
U
p. 81.
ACCIPITRES
475
A
2
there appears to be an accessory tendinous origin from the
humerus. The pectoralis primus is commonly divisible
into two layers, but not in Milvago and Dryotriorchis.
The deep flexor tendons of the foot belong in the
majority of species to type described above on p. 101. But
there are a few variations of the typical arrangement. In Astur
tibialis the slip to digit II. is present, but it is very small.
In Baza, on the other hand, the vinculum is alone present,
there being no special slip to the tendon supplying digit II.
In Dryotriorchis spectabilis, Vultuu auricularis, and
Milviis ictinus, the fibres of the vinculum are perfectly
continuous with the slip to digit II., and form with it one
single band of connection. -
Both peroneal muscles appear to be present in the
Accipitres.
All genera have the ambiens and the femorocaudal. In
Falco and Circus maurus there is also a slender semi-
tendinosus. Glutæus I. is generally absent, glutaus V.:
commonly but not always present.
The syrinx of the Accipitres is. of the ordinary tracheo-
bronchial form.
In Falco peregrinus the intrinsic muscles are inserted on
to a transversely elongate fibro-cartilaginous bar which runs
across the interannular membrane of bronchial semi-rings
1 and 2. This membrane is very wide, owing to the fact
that the first bronchial semi-ring is much arched, the con-
cavity being downwards, while the second semi-ring is equally
arched, but the concavity is upwards. None of the tracheal
rings are fused, and the last gives rise to a pessulus. F.
candicans, F. lanarius, F. biarmicus, F. Feldeggi, F. cesalon,
F. sacer are perfectly similar, and the bronchidesmus (in those
specimens in which it had been preserved) is complete.
Much like the syrinx of Falco is that of Hieracidea
berigora ; I can, indeed, detect no differences. So too
Tinnunculus alaudarius and Erythropus vespertinus. In
1
)
LT
| FORBES in a MS. note records what I call'semitendinosus' in Microlierax
coerulescens as a product of the division of the semimembranosus on account
of its origin from ischium and pubis.
476
OF BIRDS
S
STRUCTURE AND CLASSIFICATION DIVUL
11
U
Milvago chimango and M. chima-chima the syrinx is at first
sight perfectly similar, but the intrinsic muscles only just
get beyond the first bronchial semi-ring. In Herpetotheres
cachinnans this divergence from the normal falconine
syrinx is carried still further, the intrinsic muscle being
attached to the first semi-ring.
The syrinx of Polyborus brasiliensis is an exaggeration of
the falconine type. The first and second bronchial semi-rings
are very prominent and wide apart, thus leaving a very
spacious interannular membrane, to which the intrinsic
muscles are attached. The last few tracheal rings are fused
mesially in front and behind. The remaining forms, so far
as I have studied them (comprising the genera Melierax,
Nisaetus, Gypaetus, Thrasaetus, Buteo, Milvus, Spizaetus,
Urubitinga, Haliaetus, Vultur, Spilornis, Morphnus, Helo-
tarsus, Leucopternis, Circus, Aquila, Circaetus, Gyps, Archi-
buteo, Geranoaetus, and Asturina), differ from each other
in details—such as the completeness or incompleteness of
the bronchidesmus, the degree of ossification of the rings
and semi-rings, the number of the last tracheal rings which
are fused, and the attachment of the intrinsic muscles
(semi-rings 1, 2, or 3)--but they agree to differ from the
falcons in the absence of a pronounced oval gap between
the first and second bronchial semi-rings, which gives to
the syrinx of the falcons so characteristic an appearance.
The lobes of the liver are subequal, and a gall bladder
is present. The cæca of the Falconidæ are minute.
Haliaetus albicilla is a fish-eating bird, and for some
reason birds with such habits are furnished with a long in-
testine, as will be seen from the measurements in the table
on p. 477. The duodenal loop in this bird, exceptionally,
is thrown into a series of subsidiary loops, a state of affairs
which, as it occurs in the remote penguin, may have some
relation to habits and may not be a character upon which
stress is to be laid. The greater part of the intestine pre-
serves the simple archaic form of a number of irregular
coils; but near to the cæca are two spirally twisted, elongated
loops. In other Accipitres it is more usual for the upper
ACCIPITRES
477
loops to be long and twisted, a circumstance which recalls
the structure of the loops in the stork (see fig. 208, p. 437).
The following are a few intestinal measurements:

Inches
Serpentarius reptilivorus I
.
DIT
Ft. In.
6 6
7 9
6 8.5
7 6
4.5
3
Inches
•15.
.25
25
•25
1
4.5
5
1
4 10
4
1
.
5
3
o
ප
3
2
6
1.25
.
2
Gypagus papa a
Catħartes atratiis :
Polyborus brasiliensis
Spizaetus coronatus &
caligatus
Falco biarinicus f .
Milvus ictinus .
Circus Gouldi .
» @rruginosus .
Haliaetus albicilla
vocifer ga .
Aquila navioides .
3
3 11
4 7.75
3 8.5
l
2.75
une
11 2
• 25
•15
- -
.
.
2.5
8
4
7
4
-
- -
.
The skull of the Falconidæ is described and figured by
HUXLEY,' PARKER, and SHUFELDT.3 The palate is described
as desmognathous; but it is always the case that a large
portion of the maxillo-palatines—the posterior regionare
not in contact. In two skulls of Lophoaetus occipitalis the
palatal surfaces of the bones were nowhere in contact, and
were only in contact for a minute space in a skull of Vultur
calvus. Neither is Elanus desmognathous, according to
SHUFELDT. The maxillo-palatines are large and swollen.
The vomer is long and knifeblade-shaped ; 4 there is often a
medio-palatine, for instance in Halicetus albicilla, where it is
embraced by the bifurcate posterior extremity of the vomer.
The lacrymal is large and has a separate ossification, the so-
called infraorbital, attached to its posterior extremity in many
i In P. Z. S. 1867.
2 Linn. Trans. (2) i.
3 « Some Comparative Osteological Notes on the N. American Kites,' Ibis,
1891, p. 228; Osteology of Circus hudsonianus,' J. Comp. Med. 1889.
+ It has been found to be bifid in front, after the charadriiform plan, in young
of Tinnunculus (cf. SUSCHKIN, “ Zur Anat. u. Entwicklungsgesch. d. Schädel d.
Raubvögeln,' Arzat. Anz. xi. p. 767).
-478
STRUCTURE AND CLASSIFICATION OF BIRDS
hawks, for example in Haliaetus albicilla, Lophoaetus occipi-
talis, Circus Gouldi, Asturina Natteri, Astur Nove Hol-
landiæ; in others, such as Herpetotheres cachinnans, Vultur
calvus, the large size of the lacrymal suggests that such a
bone is present, but ankylosed with the lacrymal. The bony
nostrils of the Falconidæ are holorhinal, sometimes (e.g.
Herpetotheres cachinnans) reduced in extent by alinasal
ossifications; the long septum between them is more or less
perfect. The number of cervicalvertebræ, ribs, hæmapophyses,
and uncinate processes of a few types is shown in the fol-
lowing table :

Cerv.
Vert.
Ribs
Hæmapo- Uncinate
physes Processes
(8) I' + I +6.
(8) 1+1'' + 5+1
14
C10-D3
C10-D2
On 3-7
ကံ ကံ ကံ ကံ
co co oo
Herpetotheres cachinnans .
Dryotriorchis spectabilis.
Circus Gouldi.
Asturina Natteri . .
Accipiter nisus .
Astuir Nova Hollandiæ .
Lophoaetus occipitalis
Melierax monogramnicus
(9) 1+ v' + 6 +1 C10-04
14 | (10) r+v' + 7 + p' C11-D3
1 (9) 1 + 8
C10-D4
14 / (9) V + V' + 6 + r 010-04
13 / (9) V+r'+6+ v 010-D4
#
က် ကော
co co i
. !
,
O
The sternum is whole or with one pair of foramina, some-
times notches, and often only developed on one side. The
coracoids slightly overlap in Dryotriorchis, Herpetotheres,
and Melierax ; they do not quite meet in Accipiter, Lopho-
aetus, &c.
Pandion is undoubtedly an aberrant genus, which is by
several (e.g. GADOW) made the type of a separate family, and
is thought by some to lead towards the owls. It differs from
1
peculiar tensores patagii and deep plantar tendons.
The tensor patagiữ brevis has the additional'aquiline'
wristward slip, from the middle of which rises a short
recurrent slip which joins the insertion of the main tendon.
The tendon of the biceps muscle is split for nearly its whole
length.
The deep plantar tendons are not accipitrine ; they blend
completely, as in owls, hornbills, &c., the area of fusion being
Ossified.
ACCIPITRES.
479
The syrinx is not remarkable in form. Anteriorly the
last three tracheals are fused medianly; posteriorly the fusion
is more extensive, and includes the first bronchial semi-ring.
The second bronchial semi-ring is in front close to the first;
behind it is united with the third, upon which latter are
inserted the intrinsic muscles.
The skull is accipitrine and not strigine. The descending
process of the lacrymals, however, is firmly and entirely
blended with the ectethmoid, but the former bone has no
backwardly projecting frontal portion, let alone a separate
Ossification at the end of it, such as is met with in some
Accipitres. The vomer is long and ends in front in an olive-
shaped swelling which fits in between, but is not attached
to the diverging limbs of the anteriorly fused maxillo-
palatines.
Thering of the atlas is incomplete in the middle line above;
there are fifteen cervical vertebre. The hæmapophyses are
very feeble on the earlier cervical vertebræ ; they commence
on C10, where they are double ; they are strong over the last
cervical and the first three dorsals, where they end. Six
ribs reach the sternum, of which the first four have uncinate
processes. Both the tibio-tarsus and the tarso-metatarsus
have a bony bridge for tendons; the latter has one behind
as well as in front.
This bird possesses a scapula accessoria in the glenoid
capsule, the significance of which as a point of affinity with
the owlsis marred by its occurrence in toucans, &c. (see p.192).
The coracoids slightly overlap, as in some 'Accipitres.
Whatever may be thought about Pandion, it is clear
that the separation of the secretary bird to form a distinct
family, Serpentariidæ, is perfectly justifiable.?
Serpentarius has basipterygoid processes, and its muscle
formula is BXY+..
The tensor patagiż brevis is more stork or crane like than
accipitrine, and indeed resembles Cathartes in the presence of
1 The claims of Polyboroides to be a member of this family have been dis-
missed by MILNE-EDWARDS (Hist. Nat. Madagascar) and myself (loc. cit. on
p. 474).
480
-
STRUCTURE AND CLASSIFICATION OF BIRDS
a slip (see fig. 227) uniting the brevis and longus tendon. It
must be remembered, however, that this also exists in some
eagles.
In Serpentarius there is a longer attachment of the
deltoid to the humerus than in other birds of prey; and there
is an accessory biceps muscle (see fig. 227).1

INT.p.br
1
L--Bi
Bi
N
Anć
....
..
...
.
Fig. 227.-TENSORES PATAGII Or Serpentarius (AFTER BEDDARD).
t.p.7, tensor longus ; t.p.br., tensor brevis ; Bi, biceps; Bi', accessory biceps ;
Anc, anconæus ; D, deltoid.
The anconaus has a very broad tendon of origin from
humerus.
In the syrinx- a strong box is formed by the last tracheal
ring, and the intrinsic muscles are attached to bronchial
semi-ring 2.
There is a powerful expansor secundariorum.
1 Cf. Rhinochetus, p. 371.
ACCIPITRES
481
Niin
VIA
The skull has strong basipterygoid processes. The
lacrymals are large and extend backwards in close connec-
tion with the skull wall; they are not ankylosed to it. The
descending process is thin and articulates with the slight
èctethmoid. There is a small knife-shaped vomer.
The family Cathartidæ consists of the genera Sarco-
rhamphus (condor), Gyparchus (or Gypagus, king vul-
ture), Cathartes (turkey
vulture), and Rhinogry-
phus. They all have, so
far as is known, the oil
gland nude, twelve rec-
trices, no aftershaft, and ·
are aquincubital.
The tongue is large
and fleshy, with denticul-
ations of its upturned
lateral margins.
The stomach is not
a gizzard. There are no
intestinal cæca. The in-
testines are 61-inch in
Gyparchus, 49-inch in
Cathartes atratus. Of
the heart of the condor
some observations will be
found above (p. 50); both
carotids are present. The Fig. 228.-SKULL OF Serpentarius
liver is equilobed, with a
(AFTER HUXLEY).
gall bladder. There are in
palatine ; Pl, pterygoid ; x, basipterygoid process.
Gyparchus traces of a crop.
The most distinctive feature of the Cathartidæ, however,
is the windpipe, from which a proper syrinx may be really
said to be absent. The only muscles upon the trachea are
the sterno-tracheales, which (in G. papa) are very short and
broad, and arise from the sternum in the middle line, close
together between the inner ends of the coracoids. Intrinsic
syringeal muscles are entirely absent in the Cathartidæ,

SA
2
Pam, premaxilla ; Map, maxillo-palatines ; P7,
II
482
STRUCTURE AND CLASSIFICATION OF BIRDS
unless, indeed, their homologues existi in the form of a
muscular covering to the terminal purely membranous
section of the bronchus (fig. 229) which, dividing into three
slips, runs from thence to the parietes. There are in any
case no muscles at the actual bifurcation. Nor is there any
change in the character of the rings themselves such as to
suggest even the rudiment of a syrinx. In Cathartes
the rings at the bifurcation are extraordinarily thin, leav-
ing wide membranous intervals, which are occasionally
traversed by bridges putting successive rings into communi-
cation. In Sarcorhamphus and Gyparchus, which also agree
(see below) in their 'muscle formula,' the rings are thicker
and closer together (see fig. 229). And in these two genera
the bronchi are incomplete internally, giving rise to what
may be termed a membrana tympaniformis.
In Gyparchus papa the tendons of the patagium are
somewhat complicated. The brevis consists of a separate
anterior and posterior section, of which the latter is thinner
and more diffuse. The anterior tendon divides into two,
of which the foremost gives off a slip to the longus. There
is no biceps slip. The tendons, in fact, are thoroughly
stork-like, as are those of the condor (Sarcorhamphus)
and Cathartes. In this character the family is very uni-
form.
The expansor secundariorum is present in all.
The pectoralis primus is well divided into two parts, of
which the lower (in G. papa) is inserted by a thin round
tendon altogether below insertion of superficial layer. The
head of the anconæus is distinctly bifid and entirely tendinous,
arising from scapula and from supinator muscle. There is
a humeral slip of moderate size. (This muscle is described
from Cathartes.)
The ambiens is present in all Cathartidæ ; so too the
semitendinosus and its accessory. Cathartes has in addition
the femorocaudal, which is absent in the other genera. In
Gyparchus (? as to the others) the semitendinosus and semi-
| BEDDARD, 'Notes on the Anatomy of the Condor,' P. 2. S. 1890, p. 146.
ACCIPITRES
483
chartes). The
membranosus are inserted in common. There are two
peroneals (at any rate in Cathartes). The deep flexors are
fused before origin of four slips to four toes.
The gluteus I. covers over biceps, and glutæus V. is
present.
The skull of the Cathartidæ has basipterygoid processes.
It is desmognathous, but the desmognathism is totally
The gluteenigin of four

Pmx

77777
Map NIVIN
2.
an
SITARIOS
antissit
c
ndron
.
alt
wwwremont.com
vitano
ZE
"2110
D
••
.
EV
AM
IL
mann77
f
2011
11
V11
P
OS
VI
.
.
.
I 15
"
TUDUTO
03
Bell
AN
FIG. 229.-WINDPIPE OF CONDOR (ATTER
BEDDARD).
Tr, trachea ; Q', csophagus; 0, ostia of lungs; s, sp,
septa between air sacs ; m, muscles euslieathing end
of bronchi,
FIG. 230.-SKULL or Cathartes
aura (AFTER HUXLEY).
P7.x, premaxilla ; Mxp, maxillo-pala-
tiues; Pi, palatines; Pi, pterygoid ;
S, ossified septum ; %, basipterygoid
processes.
different from that of other vultures and hawks. The
maxillo-palatines proper (see fig. 230) are very far indeed
from meeting in the middle line ; indeed, they only just get
beyond the shelter of the palatines. But a flat dorsal pro-
cess of each of these bones (S) meets and is co-ossified with
1 1
2
484
STRUCTURE AND CLASSIFICATION OF BIRDS
the nasal septum in the middle line. In Gyparchus papa, at
any rate, there is a small medio-palatine. The lacrymal (at
least in Cathartes atratus) is a smallish bone completely
filling a notch in the frontal margin ; its descending process
ankyloses with the ectethmoid, forming the usual ring. In
Gyparchus papa the orbital portion of the lacrymal is greatly
reduced; the nostrils are not so elongated as in Cathartes ;
the palatal bridge is more plainly an alinasal fold. The
bony nostrils are holorhinal, but much more elongated than
in the Falconidæ; there is no trace of an ossified internarial
septum.
Of fossil Accipitres the remains of a number of different species
have been found. The most interesting of these, on account of its
age, is the Lithornis vulturinus of Owen, from the London clay.
It had been held to come nearest to Cathartes, an interesting fact
in view of its occurrence in this country; but LYDEKKER regards
it as clearly accipitrine and allied to Accipiter and Circus. Har-
pagornis, 2 from the Pleistocene of New Zealand, was a large bird,
one and a half time the bulk of a golden eagle, also belonging to
the same division of Accipitres. Teracus and Palæohierax are
extinct genera from the lower Miocene of France, known only by
femur and tarso-metatarsus respectively. They are also probably
true falcons. Serpentarius is known by an extinct form, S. robustus,
from the lower Miocene of the same country.
The following table shows the main differences between
the several families of the Accipitres :-

Falconidæ
Serpentariidae
Cathartida
+ (exc.Pandion)
Tufted
Tufted
BXY+
At
Nude
(A)XY+
t
Aftershaft
Oil gland
Muscle formula
Accessory semiremb.
Ceca . . .
Syrina. . .
Basipt. proc. . .
Desmognathis
+ (rud.) + (rud.)
Trach.-bronch. Trach.-bronch.
+
Of maxillo-pal. Of max.-pal. 1 Of alinasals
fi
DI
1. Description of the Fossil Remains of ... a Bird (Lithornis vulturinus)
from the London Clay,' Trans. Geol. Soc. (2), vi. 1841, p. 206.
2 Cf. HAAST in Trans. N. Zealand Inst. iv. 1871, p. 192, and ibid. vi. 1874,
p. 64, and Owen in Extinct Birds of New Zealand.
ACCIPITRES
485
It is clear from the few characters—the principal ones,
however-given in the above list that the Cathartidæ are
more aberrant (considering the Falconidæ to be the typical
birds of prey) than are the Serpentariidæ; for the
Cathartidæ diverge in all eight characters from the Fal-
conidæ, while the secretary vulture only diverges in three.
What reason is there, it might be asked, to retain the
American vultures within this order at all, particularly
if the owls are to be-as I think they should-excluded ?
The only group which has the distinctive characters of the
Cathartidæ (besides, of course, the present group) is that of
Herodiones. There only do we find birds with ambiens and.
expansor secundariorum, without biceps slip, holorhinal, and
with rudimentary or absent cæca. The Steganopodes also
are not far off. It really comes to the beak and claws, the
ceroma, and to the presence of various structures (e.g. the
peculiar palate, the basipterygoid processes) which forbid
their association with the Herodiones. The several groups
are not far off, but on the whole the American vultures are
more like the remaining birds of prey than like the stork
tribe (see also under the discussion of the affinities of the
Grues, p. 382).
TINAMI
Definition.-Oil gland tufted. Quintocubital. Muscle formula of
thigh, ABXY+. Expansor secundariorum present. Biceps
slip absent. Both carotids present. Large cæca and crop. Skull
dromzognathous. Tail short without ploughshare bones. Bones
of pelvis free distally.
The tinamous are purely South American birds, of which
in his recent catalogue Count SALVADORI allows nine
genera.
The tinamous have a tufted oil gland, but the tuft is often
very minute, and in Calodromas elegans consists of only four
feathers, two larger and two smaller, the larger ones being
uppermost.
I take my account of the pterýlosis of the tinamous from
486
STRUCTURE AND CLASSIFICATION OF BIRDS
6
PYECRAFT’S careful description of Calodromas (which I can ·
confirm) and Rhynchotus rufescens. In the former bird the
body is fairly covered with feathers, the apteria being narrow.
There is no down save on the wings. The spinal tract soon
divides into two; but they rejoin near the base of the neck.
These tracts again divide and reunite some way in front of
the oil gland, enclosing thus a dorsal apterion. The ventral
tracts also divide early upon the neck, and each of them
again divides on the pectoral region into a stronger, outer,
and a somewhat weaker, inner, tract. Until about halfway
down the neck the dorsal and ventral tracts are in contact.
In Rhynchotus rufescens there is no spinal apterion. The
aftershaft is much more rudimentary than in Calodromas,
where it is well developed. Both birds have ten feebly
developed rectrices. Rh. perdicarius has eight.
The aftershaft is apparently in the process of disappear-
ance among the tinamous. In Nothocercus, writes Mr. PYE-
CRAFT, “it is evidently degenerating, inasmuch as the shaft
is almost, if not quite, obsolete, only the rami remaining.'
In Tinamus solitarius the aftershaft is absent. Powder -
down patches exist in a few tinamous. They occur, for ex-
ample, in Tinamus major. In Crypturus tataupa the powder-
down patches extend down on each side of dorsal tract from
a little in front of humerus nearly to oil gland. After the
end of the scapula they thicken and spread outwards as far
as the head of the femur, and are in contact for nearly two
inches along mid-line; they then narrow again and terminate
half an inch in front, and slightly to the side, of the oil
gland.
Rhynchotus perdicarius has apparently no powder-
downs.
The tongue of the tinamous is small and triangular in
form. The crop is present and large. The proventriculus
is zonary ; the liver subequilobed, with a gall bladder.
The following are measurements of the alimentary
canal :-
LULU
Ibis, 1895, p. 1.
TINAMI
487

S. I.
L. I.
C.
Crypturus tataupa
19.75
3.75
2.5
3:3
obsoletus
sallai .
25
2.5
8.5, 9.5
Rhynchotus rufesceras
Nothura anaculosa .
19
19
3
Tinainus solitarius
4.5
The cæca, it will be observed (fig. 231, p. 488), are well
developed, particularly in Rhynchotus rufescens ; they are
also large and very peculiar in form in Calodromas. The cæca,
of this bird are not merely much wider than is customary,
but they are beset with numerous small diverticula, which
diminish in size towards the apex of the cæcum. These
peculiar cæca are absolutely unique among birds, and nothing
at all like them has been described in any other tinamou.
A curious feature of at any rate some tinamous (shared,
however, by the Anseres, Palamedeidæ, some gallinaceous
birds, and perhaps Toccus) is the existence of two pairs of
extrinsic muscles upon the trachea. In Crypturus tataupa
one of these pairs is stouter than the other, and they are both
lost on the fascia covering lungs. This genus has no intrinsic
muscles.
In other tinamous intrinsic muscles are present.
In Calodromas elegans the anterior face of the lower part
of the trachea (about an inch in length) is covered with a
sheet of muscle, which is the extrinsic muscle, and probably
(judging from the conditions which obtain in the female) is
attached to the long fascia. The very broad intrinsic mus-
cles underlie this, and are inserted a long way down the
bronchus to the four or five rings following the third. When
viewed laterally the curvature of the last four tracheal rings
is seen to gradually increase; there is thus a considerable
membranous interval left between the last tracheal and the
first bronchial, which is straight. The membrana tympani-
formis is narrow. In the hen bird the extrinsic muscles are
BEDDARD, 'On the Cæca of Calodromas,' Ibis, 1890, p. 61.
488
Y
STRUCTURE AND CLASSIFICATION OF BIRDS
.
.
*
"
.
7
.
NL
.
OH
.
::
TRADA
..
.
.
-
•
.
OH'
O
.
***
RAIS
.
217E
2.
.
4
I'T
VA
.
ATHAN
.
will
IN
TIR
on
.AHHII
UNIT
WWW.
*
..
11
V14
I!
III.
DIA
.
.
U
.
A
20
M
CAS
$
.
14
UNI
W
..
WW
. NULLA
.
.
Diy
WS
.
*
27
.
CHES
AM
NA
117
*
NIHA
SU
TOUUNIT
X
ANE
*
1
*
.
AVE
*
O'RIBUS
MYNAI
-
1
.
.
RUDO
.
ANY
12...
.
22.
SI.
UW
U
.
.
it.
. XX
.
-
VAN
:
.
!
HO
lu
AD11'.
O
.
lol
NATA
CARA
KO
P
.
A
Hii
w
.
.. MY
'.
.
***
..
CA
ti
..
.
1371
A
.
.
IA
.223
$
101
S
.
.
.
.
.
PARA
.
SER
12
Y-
M
.
.
-
-
-
TE
S.), small intestine ; L.1, large intestine ; C, cæca.
BEDDARD).
FIG. 231.—CÆCA or Calodromas elegans (AFTER
-
-
TV
.
ANXV.
Ist...
.
.
W
SI
RS.
-
A
.:
W
SUI
.
.
.
.
.
.
Nº.
View
..
IV
-
-
.
B
.
.
,
.
.
.
dt
.
S
W
W
ill"
.
.
IN
.
AN
!
22
J
?
er111
.
YNNE..
N
.
.
VA
.
.
.
lin
.
.
.
.
*
*
TILL
eta
NAR
XL
WL
PROWIWIRAS
S
tillllllllllll
TRAW
anna
1/12
WY:
ME
4
.
V
Su
ir
II
th
X
E
..ti
TS
ht
M
M
VINE
112
AV
US
21
ON
.
C
Z
CORT
MINO.
.
CENI
LUK
DU
.
A
XV i
W
O
>
al
l
iit
.
micili
TE
w
URI
.
2
CILIK
.
.
VA
•
AN
.
..1
W
1111/YIN
lii
W
N
MENTO
VII.
TI
UNT
the trachea.
small, and do not form a sheet of muscle covering the end of

.
.
ZE.
.:
"
22
DIINA
D
.
WL
20
.
.
*
1
MUS
MESMO
*
A
C
2
SVWHI
2
.
TAL
AN
Z
WA
P
et
de
online
NO.1
.
No.
!
ON
el
L
he
XIII
111
1.
.
U
.
V2
1
RSS
!
si
-
.
TA
Ll-
y
CA
15
LA
35
WOW
TEST
.
.
.
062
-
-
XX
NA
1
-
-
I
-
-
-
19
P4
VA
S
-
.
UR-
22
1.
R *
Seti
T
G
E
E
st
:.--
L
.
.
.
AN
IN FIG. 231.
BEDDARI)). LETTERS AS
thuru maculosa (AFTER
Fig. 232.-CÆCA OF No-
Sh.
.
.
UR
.
S
TINAMI
489
.
In Tinamus solitarius the intrinsic muscles are large and
are inserted upon the fifth or sixth bronchial semi-ring. In
Rhynchotus rufescens they are also large, but attached
higher up.
The muscles 1 of the tinamous are remarkable on account
of their soft texture and pale colour. The pectoralis I. is
very large and meets its fellow of the opposite side and for
a considerable portion of its extent. The actual junction of
the fibres is prevented by a fibrous septum, which is a con-
tinuation of the carina sterni. The second pectoral is also
large. The tensor patagii tendon is a broad diffuse band, as
in gallinaceous birds ; it has no biceps slip unless a muscle
that will be referred to in connection with the biceps
immediately really represents this. The biceps itself pre-
sents no remarkable features, but a kind of accessory biceps
runs along the front of the humerus, which is quite distinct
from the biceps proper ; I have found this both in Calo-
dromas and Rhynchotus. This is regarded by FÜRBRINGER
as part of the coracobrachialis externus.
In Crypturus (as also in gallinaceous birds and sand
grouse-a noteworthy fact, perhaps) the pectoralis abdomi-
nalis has a remarkable ending.
Instead of being inserted directly upon the humeral crest
it ends upon a tendinous bridge, to which are also attached the
pectoralis, the latissimus dorsi posterior, and the expansor
secundariorum.
The tinamous have the gallinaceous muscle in the fore
arm and the expansor secundariorun. The anconcus has a
humeral slip.
In Crypturus tataupa and Nothura maculosa at any rate
the expansor secundariorum. ends in a tendon which is
inserted on to the scapula on the one hand and the manu-
brium sterni on the other.
The tinamous have the complete muscular formula of
the leg, i.e. ABXY+.
It
JU
LI
רן ו
I ALIX, “Sur la Myologie du Rhynchotus rufescens,' Journ. de Zool. v. (1876),
p. 411. "Mémoire sur l'Ostéologie et Myologie du Nothura major,' Journ.
Zool. iii. 1874, pp. 167, 252. .
490
STRUCTURE AND CLASSIFICATION OF BIRDS
Pms.
.
.
I
.
SA
RE
FO
The glutæi I.-V. are well developed. A very interesting
feature of the thigh muscles (referred to by GARROD 1) is the
existence of a small “suprasciatic' slip of muscle arising
behind the acetabulum, which reinforces the accessory
femorocaudal. The interest of this small muscle lies in the
fact that it has its precise counterpart in the struthious birds
(q.v.) This muscle was found by FORBES to be absent in a
male Crypturus tataupa; it was present
in a female of the same species.
The two deep flexor tendons fuse and.
then supply digits II.-IV. ; before uniting
the flexor hallucis gives off a slender slip
to hallux, which is wanting in Crypturus
Map
undulatus.
The skull of the tinamous, as was
VO
first pointed out by PARKER,2 is com-
pletely 'struthious 'so far as concerns the
palate. As will be seen from the annexed
cut (fig. 233) the vomer is broad and unites
in front with the maxillo-palatines, as in
Dromæus. Its ends receive behind the
pterygoid and palatines, which are thus
prevented from articulation with the
basisphenoidal rostrum. There are large
basipterygoid processes and the head of
Fig. 233.-SKULL OF
Tinamus robustus the quadrate is single, as in struthious
(AFTER HUXLEY). birds. The supraorbital chain of bones
ille: Manifigured by PARKER in Tinamus robustus
tines; is another archaic skull character of these
Pl, pterygoids.
birds. The nasals, lacrymals, and
adjoining bones are very much like those of Rhea and not at
all like those of gallinaceous birds. Between the nasals
posteriorly is a considerable tract of ethmoid, appearing

ws
.
.
N
OU
>
SO
ATUA
.
WW
maxillo-palatines; 10,
vomer; PT, palatines ;
T' On certain Muscles of the Thigh of Birds,' &c., P. Z. S. 1873, p. 642.
2 On the Osteology of Gallinaceous Birds and Tinamous,' Zool. Trans. V.
3 Absent, according to LUCAS ( Notes on the Osteology of the Spotted
Tinamou,' Proc. U. S. Nat. Mus. X. 1887, p. 157), in Nothura mraculosa.
4 Prof. PARKER wrote, in 1862 (loc. cit. p. 213): 'I suppose that in the tina-
mou, as in other ostriches, the broad top of the ethmoid is separately developed
TINAMI
491
upon the surface of the skull. The outer descending part of
the nasal reaches the maxilla, and with the upper part of the
bone encircles the holorhinal nasal foramen; it is not
ankylosed with the lacrymal. The latter descends and
articulates with the jugal by a very distinct facet, especially
distinct in Rhynchotus rufescens. The bone also becomes
fused with the lateral wing-like process of the ethmoid,
forming a complete ring of bone round a relatively very
wide foramen. A special point of resemblance to Rhea and
Dromcus is the perforation of the descending process of the
lacrymal itself. This is best seen in Rhynchotus rufescens ;
in Calodromas elegans, Nothura maculosa, and Crypturus
tataupa, there is merely a notch which in the fresh skull may
possibly be converted into a foramen by a ligament."
FÜRBRINGER gives 16-18 as the number of cervical
vertebre. The cup of the atlas is perforated for the odontoid
process in Crypturus, Rhynchotus, and Nothura. As in
the gallinaceous birds, &c., some of the dorsal vertebræ are.
fused together. In Tinamus solitarius this was the case with
the first three and to a less extent with the last cervical. In
Nothura maculosa five vertebræ were thus fused, and a
strongish longitudinal piece of bone, formed of ossified liga--
ment, connected their transverse processes. In Crypturus
tataupa there were four vertebræ fused and one in front
partially so. Four ribs reach the sternum in Tinainus
solitarius. The sterium of the tinamous is very remarkable
in form. The manubrium is slightly bifurcate; the middle
portion of the sternum, which bears the keel, is exceedingly
narrow, and a wide space is left on each side between it
and the lateral processes, which are thin and as long as
the middle piece. The anterolateral processes are well.
developed
The pelvis is so far on the struthious pattern that the
1
NI
ILI
T
U
VEVO
by a long piece growing from above downwards between the anterior ends
of the frontals. No suture remains to tell me that; but if it be so all is
perfectly struthious, for those birds differ in this from all others examined
by me.'
1 This, however, is not a unique feature of the birds in question. It occurs,
for example, in Tantalus and Xenorhynchus.
i
492
STRUCTURE AND CLASSIFICATION OF BIRDS
three bones do not fuse posteriorly; the pectineal process is
large.
There are at most faint traces of a ploughshare bone.
In Crypturus the clavicles come into contact with the .
acrocoracoid and the scapula, but not with the small pro-
coracoid.
The two coracoids are not nearly in contact at their
articulation with the sternum.
The only birds with which the tinamous have been com-
pared are the ostrich tribe, the gallinaceous birds, rails,
bustards, and some of the Limicolæ. PARKER saw in the
tinamou a'cock ostrich mule ;' and perhaps the prevalent
opinion is that they lie on the confines of these two groups.
It is unquestionably to the Struthiones that they show the
greatest number of important likenesses, so much so, indeed,
that their inclusion in one great group with them would be
by no means an unreasonable way of disposing of them.
The salient points of resemblance are by no means confined
to the skeleton, but the most numerous resemblances are in
that part of the body of the birds. The skull, with its
dromeognathous' palate, is strikingly like. The appearance
of the ethmoid as a median ossification of the skull roof is
struthious, but it also occurs, though not so markedly, in
Gallus and (according to SELENKA) in the Caprimulgidæ. It
is very conspicuous in the tinamou and the Struthiones. The
open pelvis is especially like that of Apteryx. The single-
headed quadrate is struthious; but, as already mentioned,
the struthious birds are not uniform in this character.
The sternum, with its antero-lateral and postero-lateral
processes, recalls that of Apteryx, in spite of the enormous
length of these parts and a consequent superficial dissimi-
larity. The absent, or rudimentary, ploughshare bone may
perhaps be passed over as correlated with the imperfect
flight. As to the soft parts, the peculiar additional accessory
1 A singular if less important likeness than some mentioned above has been
referred to by Mr. BARTLETT (* Notes on the Breeding of several Species of Birds,
&c., P. 2. S. 1868, p. 114). The male Rhynchotus 9.21fescens incubates, as in
the Struthiones, while the chick' much resembles the young of a Rhea.'
TINAMI
493
femorocaudal muscle is a striking resemblance to the Stru-
thiones; the peculiar accessory biceps muscle of the arm
may have its degenerate counterpart in a sheet of strong
tendinous tissue which runs along the humerus in certain
ratites.
The following table shows some of the more striking
likenesses of the Tinami to the Struthiones and Galli :-

Tinami
Struthiones
Galli
Skull . . . Dromæognathous Drom. | Schizognathous
Pelvis
Bones free Bones free or Ischia and ilia
but little united fused posteriorly
Oil gland.
Tufted
Tufted, or nude,
or 0
Remex V.. .
+ ?
Leg muscles . .. ABXY+ (A)BXY(+) (A)BXY +
Suprasciatic muscle.
Entepicondylo-ulnaris
In Apteryx
Trachea . . . Sometimes with Only one pair | Sometimes two
two pairs ex-
pairs
trins. muscles
to
STRUTHIONES
Definition.-Flightless birds without stiff contour feathers. Oil gland
absent. Wing small. Expansor secundariorum and biceps slip
absent. Semitendinosus and its accessory always present. An
additional slip to accessory femorocaudal present. Skull
dromeognathous with basipterygoid processes; holorhinal.
Sternum without a well-developed carina. Coraco-scapular
angle wide. Coracoid fused with scapula. Cæca large.
As will be seen from the above definition, the characters
of this group are to a considerable extent negative characters.
They are for the most part such characters as are correlated
with the loss of the power of flight. We need not, therefore,
lay too much stress upon them as indicative of the natural-
ness of the group. But even when these characters (as, for
instance, the absence of the carina sterni, the open angle
between the coracoid and scapula, the absence of a plough-
share bone, which, moreover, is occasionally and exception-
ally present. There is a skeleton of an old Struthio in the
Cambridge Museum in which several of the last vertebræ
494
STRUCTURE AND CLASSIFICATION OF BIRDS
are fused) are set aside as comparatively valueless as marks of
near relationship, there remain enough anatomical resem-
blances to justify the older view that all these birds are but
members of one and the same group. FÜRBRINGER has
denied this in his · Untersuchungen,' and places Apteryx,
together with the Dinornithidæ, apart from the other stru-
thious birds, and has again separated Struthiiformes from
Rheiformes and Casuariiformes, deriving all from different
levels of the ornithic tree. There is no doubt that the
various types of struthious birds do require separating into
at least six families; but the likenesses among them appear
to me to forbid any wider separation. The close resemblance
of the palate throughout the group, so far as we know it
(Æpyornis is not known), is a strong reason for associating
them together; perhaps even the osteological and other
characters, which, as already suggested, are but evidence of
the loss of the flight power, may be of more importance as
an argument for affinity than is generally admitted; it may
show that they are allied, because the degeneration has pro-
ceeded along the same lines. There is, it is true, not a great
deal of evidence in favour of this view; but we have the
penguins also with a degenerate wing, in which the modifi-
cations of structurel have progressed along different paths.
They have, for example, lost the biceps, which is present in
all Struthiones, while the feathers of the wing are equally
inefficient as aids to flight with those of the Struthiones, but
are quite unlike them. The peculiar muscle of the thigh,
which will be found described as an adjunct of the accessory
femorocaudal, is one of those apparently small facts of struc-
ture which, on account of their very minuteness, seem of
importance as a mark of true relationship.
The fact that all of the struthious birds have large or
moderately developed cæca is further evidence of affinity.
It might be thought that the usual absence of the oil gland
was one of those characters affording clear evidence of degene-
ration; but its capricious appearance and disappearance in
See, however, the qualifying remarks with regard to the wings of Apteryx
on p. 499.
STRUTHIONES
495
UUU
other birds forbid us to assume this without any further
argument.
While the Struthiones present collectively and individually
a larger number of important differences from other birds,
their organisation is essentially on the plan of that of the
remaining members of the class. To take only one-at the
same time one of the most striking-of these correspondences
in anatomical structure, the respiratory organs may be con-
sidered. It is hardly too much to say that there are not even
differences of detail in the arrangement of the lungs and air
sacs among the struthious birds. Professor HUXLEY ex-
ploded some years ago the idea that the oblique septa of the
Apteryx were more like the mammalian diaphragm than the
corresponding structures of other carinate or ratite birds. It
is inconceivable that there should be this minute correspond-
ence of detail with detail, if we are to assume with some
that the struthious birds have arisen from a totally different
stock from that which produced the carinates. They would
derive the former from the dinosaurs and the latter from the
pterodactyles.
The existing struthious birds are the genera Struthio,
Afro-Arabian in range; Rhea, South American; Dromaus,
Australia; Apteryx, New Zealand; and Casuarius, Australian
region. The structure of these living members of the group
will be considered first, after which some account will be
given of the Dinornithidæ and other extinct and undoubted
members of the group, as well as of a few dubious forms
which have been placed here-rather because they do not
definitely fit in anywhere in particular than from their
obvious affinities with the Struthiones.
The genus Struthio appears to contain two species, the
more common Struthio camelus and the Somaliland S.
molybdophanes. The ostrich has two toes, Nos. III. and
IV. There is no oil gland. The pterylosis, continuous in
the adult bird, shows two distinct apteria in the embryo, as
has been shown by Miss LINDSAY.' In the young chick
1. On the Avian Sternum,' P. 2. S. 1885, p. 684. See also W. MARSHALL,
· Beobachtungen über das Verhältniss der Federn,' &c., Zool. Gart. xvi. (1875),
496
STRUCTURE AND CLASSIFICATION OF BIRDS
I
there is a ventral apterion in the sternal region and a lateral
apterion outside each half of the ventral tract. The adult
ostrich has a claw on each of digits I. and II. The arrange-
ment of the wing feathers has been carefully worked out by the
late Mr. WRAY.He finds the remiges to be quite distinct,
as well as the tectrices majores; the tectrices mediæ are but
scantily represented, and there is an incomplete row of
tectrices minores. The number of remiges upon the hand,
including one upon the carpus, is sixteen. There are four
to the ala spuria. The number of cubitals is about twenty.
It has, therefore, more primaries than any bird except the
penguin.
The genus Apteryx, entirely confined to New Zealand,
consists of three or four species, viz. A. australis, A. Mantelli,
A. Oweni, A. Haasti, and A. Bulleri.
It has been described as possessing a continuous, un-
interrupted plumage ; but this, according to T. J. PARKER, 2
IV
he remarks, 'I find the lateral apterium to be fully 2
cm. wide, and to extend about 5 cm. cephalad and 9 cm.
caudad from the axilla, its total length being, therefore,
about 14 cm. In the same specimen the ventral or inferior
space was of about equal width (2 cm.), and extended about
11 or 12 cm. caudad from between the origins of the wings.
Moreover the inner (ventral) surface of the wing is always
nearly devoid of feathers and so constitutes a well-marked
lower wing-space.'
The oil gland is present and the feathers have no after-
shaft.
The relatively minute wing of the Apteryx has a true
alar membrane, which, as PARKER has justly pointed out, is
further evidence for regarding this bird as the derivative of
a flying form.
p. 121, and ZANDER, - Über das Gefieder des afrikanischen Strausses,' Schi.
phys.-ök. Ges. Königsb. xxix. 1889, SB. p. 31.
1.On some Points in the Morphology of the Wings of Birds,' P. Z. S. 1887,
p. 343.
? Observations on the Anatomy and Development of Apteryx,' Phil. Trans.
1891.
STRUTHIONES
497
Though no rectrices can be distinguished, there are
recognisable remiges. PARKER counted nine or ten cubitals
and two or three metacarpals and a single mid-digital; there
are also tectrices majores. An extraordinary peculiarity of
Apteryx is the situation of the nostrils near the very end of
the beak.
Of Casuarius there are some ten species which are found
in several of the islands lying to the north of the continent
of Australia, such as New Britain, Ceram, &c., as well as
one species, Casuarius australism in the north of Australia
itself. They are remarkable externally for their black
coloration, brown in the young, and for the horny casque
upon the head. The neck is naked and adorned with
bright colours, in which blue is especially prominent, and
there are often dependent folds of bright-coloured skin in
this region. The feathers have an aftershaft as large as
the feather itself; the rectrices are unrecognisable, but the
remiges are present in the shape of long spines which corre-
spond to the stems of the feathers. The claw of the inner
of three toes is very elongate.
The emu, Dromeus, is entirely Australian in range, and
contains two species. This genus, agreeing with the casso-
wary in laying a green egg, has no helmet or wattle, or stiff
spines upon the wing. It has, however, like the cassowary,
a large aftershaft.
The fourth genus of Struthiones is the South American
Rhca, of which three species are recognised. These have
been carefully compared by GADOW. The genus is cha-
racterised, so far as external characters are concerned, by
the want of an aftershaft and by the feathered neck-not
naked, as in the ostrich ; it lays a yellowish white egg. The
Rhea is three-toed. There is a distinct ventral apterion
running from sternal callosity to vent.3
I G. DUCHAMP, 'Observations sur l'Anatomie du Drom@us,' Ann. Sci. Nat.
(5), xvii. 1873.
?" On the Anatomical Differences in the Three Species of Rhea,' P. Z. S.
1885, p. 308.
3 • A. BOECKING, De Rhea Americana, Diss. Inaug. Bonn, 1863; J. F.
KK
-498
STRUCTURE AND CLASSIFICATION OF BIRDS
Struthio has been found fossil in the Siwalik Hills, in South
Russia and Samos. Rhea is found fossil in America (South).
LYDEKKER considers Hypselornis sivalensis, whose place of inter-
ment is indicated by the name, to be an emu. It is only known
from the second phalanx of the third digit of the pes.
Genyornis Newtoni, from Australia,' with a skull a foot long,
seems to have been a gigantic emu. But it has not as yet been
fully described.
Dasornis londinensis (from the Eocene clay of Sheppey) is
placed by FÜRBRINGER among the Ratites, rather in deference to
the opinion of Sir R. OWEN ? than from conviction. GADOW, on
the other hand, places it among Stereornithes. It is only known
by a water-worn skull fragment, indicating á skull as large as that
of the Dinornithidæ. It seems useless to speculate upon the
affinities of this fragment.
Macrornis of SEELEY must remain for the present a namė.
C
In surveying the muscular system of the Struthiones 3 it is
clear that, so far as concerns the muscles of the manus,
Apteryx is, in accordance with other reductions in the bones
of that limb, the most degenerate type. On the other hand
(assuming, of course, the derivation of the Struthiones from
some carinate form) the shoulder girdle of Apteryx has
retained more of the primitive musculature than the other
genera.
In all the genera the following muscles have disappeared :
the pectoralis propatagialis, biceps propatagialis, deltoides
propatagialis, 4 deltoides minor, scapulo-humeralis anterior,
expansor secundariorum."
The pectoralis major is in all very reduced..
All the struthious birds except Apteryx have also lost the
VAN BEMMELEN, Onderzoek van een Rhea-Embryo,' Tijd. Ned. Dierk. Ver.
1888, p. cºv,
STIRLING and ZIETZ, 'Preliminary Notes on Gerlyornis,' &c., Tr. Roy. Soc.
S. Australia, xx.
? On Dinornis (part xiv.), Tr. Zool. Soc. vii. p. 145, pl. xvi.
3 GADOW, Z117 vergleichenden Anatomie der Muskulatur des Beckens und
der hinteren Gliedinäisse der Ratitenz. Jena, 1880.
1 In Apteryx some elastic tissue in the patagium possibly represents this.
5 Traces have been asserted to exist in Apteryx and Droincus, but require
confirmation.
STRUTHIONES
499
TO
10
n
serratus metapatagialis, the latissimus dorsi metapatagialis,
and the pectoralis abdominalis.
On the other hand Apteryx has lost what the other
struthious birds have retained, the latissimus dorsi anterior
and the rhomboideus profundus; the latter muscle, however,
is not distinguishable in the cassowary.
It must be admitted, therefore, that Apteryx, so far as
concerns the anterior extremity, has diverged from the
hypothetical ancestral condition in slightly different lines from
other Struthiones.
In the cassowary' both rhomboidei are present, but they
originate from ribs and not from the cervical vertebræ.
The rhomboideus profundus is parallel with and hardly dis-
tinguishable from a portion of the serratus profundus; hence
FÜRBRINGER is indisposed to admit the existence of a sepa-
rate rhomboideus profundus.
The serratus superficialis consists of two separate fan-
shaped bands of muscle. The coraco-brachialis internus is
entirely converted into tendon. The biceps originates only
from the coracoid, and ends without being definitely split
into two tendons upon both radius and ulna. There is only
one scapulo-humeralis muscle, which is, however, of fair
size.
: The subscapularis is a single-headed muscle arising from
the scapula only.
The anconcus has a single origin from the scapula, and
has no attachment to the humerus.
In the hind limb all five glutæi are present; they are all
large, especially gl. I. and gl. V. The ambiens is absent as
a rule; it is occasionally present, but is then imperfect,
reaching only as far as the knee. The 'semitendinosus and
its accessory are well developed. The femorocaudal is a
small slender muscle ; it is inserted in common with the
accessory, which is enormous in size. In Casuarius Bennettii
at any rate there is an additional adductor of peculiar origin;
the muscle is two-headed, one head being a tendon which
1 J. F. MECKEL, ‘Beiträge zur Anatomie des indischen Casuars, Arch. f.
Anat. 2. Phys. 1830, p. 200, 1832, p. 273.
LOL
Y
K
2
K
500
STRUCTURE AND CLASSIFICATION OF BIRDS
springs from the muscular fibres of the accessory femoro-
caudal, the other fleshy and springing from the pelvis
just behind the acetabulum. It is inserted along the femur
below the vastus internus and over the conjoined femoro-
caudals.
In Struthio the rhomboideus superficialis arises, as in
carinate birds, from the spingus processes of the vertebræ
(1-3 cervicals); it is inserted only on to the scapula. The
rhomboideus profundus arises from the spinous processes of
the last cervical and first dorsal vertebræ ; it is inserted on to
the end of the scapula. The serratus superficialis of Stru-
thio is a single muscle arising as two or three bands, either
from the last cervical and first dorsal rib or, in addition,
from the second dorsal rib. It is attached to the ventral
border of the scapula. The serratus profundus is divisible
into a more superficial and a deeper layer; the former is
the less extensive, and arises either by a slip from the rib
of cervical vertebra 19, and by two slips from the last
cervical rib, or by two larger slips and one very small one
from between the last cervical and the first dorsal rib, and
from the latter; they are inserted on to the inner border of
the scapula. The deeper layer also varies, but arises in
several slips from the last two cervical ribs. It is also
inserted on to the inner border of the scapula. The coraco-
brachialis externus is very large as compared with the same
muscle in the carinate birds; it is not quite so large as in
Rhea. The coraco-brachialis internus is larger in Struthio
than in any other ratite. The biceps arises from the spina
1
inserted on to the radius and ulna, and on to the membrane
between them. As with Rhea the deltoid arises from the
scapula and neighbouring region of coracoid. The teres
major, again, as in Rhea, is a comparatively large muscle.
On p. 87 et seq. will be found an account of the muscles of
the hand in Palamedea, which I have taken to illustrate that
The differences which are to be noticed in Struthio are,
apart from minor divergences, the following: -
STRUTHIONES
501
1
The extensor metacarpi radialis is single.
The ectepicondylo-ulnaris is absent or fused with the
extensor metacarpi ulnaris.
The extensor digitorum communis supplies only the
index.
. The two pronators form only one muscle.
The flexor digitorum sublimis and the fl. dig. profundus
arise by a single head from the flexor condyle of the humerus.
The two muscles immediately divide; the upper part (=
sublimis) ends in two tendons, of which one is inserted on to
radiale, the other fuses with the upper tendon of profundus,
and also gives off two slips which surround that tendon and,
reuniting, fuse with the lower tendon of the profundus. The
lower part of the muscle (= profundus) gives off two ten-
dons, of which the upper ends on the first metacarpal, while
the lower runs to the base of the last phalanx of the
index.
The flexor metacarpi ulnaris ends fleshily on ulnare, but
is prolonged beyond this bone, receiving also some fibres
from it, to the metacarpal.
The radio-metacarpalis ventralis-or at least a muscle
which, if it be not this, is not found in Palamedea-arises
from the ulna and not from the radius.
The total number of muscles in the hand of the ostrich
is twenty-three, allowing for the absent ectepicondylo-ulnaris.
The additional muscle is a small pronator quadratus, running
from the ulna to the radius.
It appears, therefore, that, in spite of the small size of the
manus of the ostrich relatively to that of flying birds, there
is but little if any evidence of degeneration in its musculaturę.
On the contrary, indeed, for it might be said that the wing
muscles of Struthio are less degenerate, or at any rate less
modified, than those of carinates in that amount of muscle
as compared with tendon is greater. The complication of
the conjoined flexores digitorum is highly suggestive of a
walking or climbing animal. It seems to be conceivable
that the ostrich branched off from the avian stem before the
power of flight was perfectly established.
502
STRUCTURE AND CLASSIFICATION OF BIRDS
The ostrichl has the complete leg muscle formula
ABXY+.
The femorocaudal is fleshy, but not large, and has no
distinct tendon of its own. It blends above with the acces-
sory. The accessory femorocaudal is an enormous muscle
ending in a broad thin tendon' which distally is lost in a
fibrous expansion round the great vesseis and nerves of the
thigh. The accessory semitendinosus is small. The tendons
of the semimembranosus and the semitendinosus become
united just after the attachment to the latter of the acces-
sory; they soon, however, diverge, the semimembranosus
being continued as a long thin tendon down the leg to join
the tendon of the gastrocnemius. The obturator externus
and the adductors are small ; the obturator internus is very
large. The ambiens does not arise from the pectineal pro-
cess, or even from the pubis, but from the ilium. An
additional adductor muscle which has been referred to in
the cassowary also exists in the ostrich ; it has, however,
but one (tendinous) head, arising from the femorocaudal
muscle.
The rhomboideus superficialis of Rhea 2 springs, like that
of Struthio, from the spinous processes of the cervical verte-
bræ, but from a larger number (four). It is inserted on to
the coracoid as well as the scapula. The rhomboideus pro-
fundus arises from the spinous processes of the first three
dorsals. As in carinate birds the serratus superficialis is
composed of an anterior and a posterior section ; the former
arises as a single band from the last cervical rib, and is
attached to the front part of the scapula ; the latter is large
and consists of three broad slips springing from the first
three dorsal ribs and their uncinate processes; it is attached
to the hinder end of the scapula. It may be, FÜRBRINGER
thinks, that a portion of this is really the pars superficialis
i S. HAUGHTON, 'On the Muscular Mechanism of the Leg of the Ostrich,'
P. R. Irish Ac. ix. (1866), p. 50; A. MACALISTER, 'On the Anatomy of the
Ostrich,' ibid. 1867, p. 1; Alix, “Sur l'Appareil Locom. de l'Autruche de
l’Afrique, Bull. Soc. Philom. 1868.
? S. HAUGHTON, ' Muscular Anatomy of the Rhea,' P. R. Irish Ac. ix. (1867),
p. 497.
STRUTHIONES
503
of the serratus profundus; otherwise that muscle only con-
sists of the deeper portion which arises as two slips from the
last two cervical ribs and runs directly backwards to be
inserted on to the lower border of the scapula.
The coraco-brachialis internus is largely tendinous ; its
origin, contrary to what is found in other Struthiones, just
extends on to the sternum. The origin of the biceps is.
peculiar; it arises not only from the coracoid spine by a
rounded tendon, but also by a sheet of tendon edged with
muscle from the whole of the coracoid and from just an
adjacent bit of the sternum. It is inserted on to both radius
and ulna.
In the manus of Rhea, on the other hand, we have more
evidence of degeneration than in Struthio. There are, in the
first place, only twenty-one muscles at most, and some of
these are much simplified.
The muscles that appear to be totally wanting are (1) the
extensor digitorum communis, (2) the pronator profundus.
The extensor indicis is only represented by the belly
arising from the wrist. The flexor sublimis may possibly be
represented by a slip of muscle arising from the tendinous
edge of the flexor metacarpi ulnaris, which goes to beinserted,
partly by tendon, partly by fleshy fibres, on to the ulnare and
base of metacarpals 2 and 3.
As in the ostrich the radio-metacarpalis ventralis arises
from the ulna. In Rhea there is a special peculiarity in the
presence of a muscular slip running from the tendon of the
extensor metacarpi ulnaris near to its insertion to the extensor
indicis. Finally the ectepicondylo-ulnaris is distinct.
In the leg there is no femorocaudal, the formula being
BXY+. The accessory femorocaudal is enormous, and there
is a good struthious accessory adductor. Glutaus primus is
very large and overlaps biceps; gluteus V. is present and
large.
In Dromæusl the rhomboideus superficialis and pro-
1
! S. HAUGHTON, ‘Muscular Anatomy of the Emu,' P. R. Irish Ac. ix. (1867),
p. 487; G. ROLLESTON, 'On the Homologies of certain Muscles connected with
the Shoulder Joint,' Trans. Linn. Soc. xxvi. 1870, p. 609.
504
STRUCTURE AND CLASSIFICATION OF BIRDS
fundus arise from ribs, the latter from only one, the former
from three.
: The biceps apparently arises like that of Rhea.
In the leg the ambiens and the femorocaudal are wanting,
the formula being, therefore, BXY-. All the gluteals are
present, and the first covers the biceps. The accessory
femorocaudal is very large, but it does not appear to
possess the struthious accessory muscle.
The muscles of the wing of Apterys are, of course, de-
scribed by OWEN in his account of the anatomy of the bird.
But a fuller and later description, with illustrations, is to
be found in T. J. PARKER'S paper upon Apteryx, and in
FÜRBRINGER..
There is no rhomboideus profundus. The serratus super-
ficialis is one muscle arising from the first two cervical ribs ;
it has the pars metapatagialis wanting in the other ratites.
There is also a pectoralis abdominalis wanting elsewhere, but
no latiss. dorsi anterior. The latiss. dorsi metapatagialis is
well developed.
The muscles running from the shoulder girdle to the
humerus are reduced to six; these are the two pectorals, the
deltoides (single), the teres major, the coraco-brachialis longus,
and the c. br. brevis
The biceps is single-headed, arising from the coracoid ; it
has long tendons at each end and a small belly in the middle ;
it is inserted only on to the radius. The anconcus longus
fuses early with the single-headed triceps.
As might be expected from the presence of but a single
finger, the muscles of the hand are much reduced. Perhaps.
the most noteworthy peculiarity is the presence of the gallina-
ceous and tinamine muscle, the entepicondylo-ulnaris.
There is a peculiar accessory brachialis anticus, seemingly
only met with in Apteryx. The remaining ten muscles are
brachialis anticus, ectepicondylo-ulnaris, ectepicondylo-
radialis, pronator (? sublimis or profundus), extensor meta-
carpi ulnaris, extensor indicis longus, with one head from
contiguous surfaces of radius and ulna inserted in A. australis
on to carpo-metacarpus, in A. Bulleri on to base of distal
STRUTHIONES
505
1112
phalanx, extensor longus pollicis I inserted on to the thumb
side of the carpo-metacarpus, flexor digitorum profundus,
ulni-metacarpalis ventralis.2 "In one specimen (A. australis)
a minute tendon was seen preaxial of that of the deep flexor
and passing to the preaxial side of the carpo-metacarpus,' a
rudimentary interosseous dorsalis in
one specimen of A. Bulleri. .
In the leg the muscle formula is
complete.

WOW
.
CZCd
.:.
S.
A
:
.
sir
.
RON
AYTI
"
REN
.
.
.
=
L
2
The tongue in all these birds is
a flat triangular organ, relatively small
in size. The accompanying cut (fig.
234) shows its characters in Rhea;
it does not show any differences of
importance in the other genera.
The course of the intestine in
Struthio camelus is shown in 'fig.
12, p. 28. It will be observed that
it is in many respects exceedingly
simple : thus the greater part of
the small intestine is thrown into a
series of short folds, with none of
the longer and more specialised folds
found in many other birds. The
duodenal loop is the only part of the FIG. 234.-TONGUE AND
small intestine which shows a special
WINDPIPE OF Rhea Dar-
wini (AFTER GADOW).
fold, and this is a loop with a short , ligpoglossal nerve.
lateral diverticulum-Y-shaped, infact.
The next most characteristic feature of the intestines of this
bird is the enormous large intestine, which is for the greater
part of its extent thrown into folds like those of the small intes-
tine. In Casuarius (see fig. 11, p. 28) the small intestine is
quite as simple as that of the ostrich; the large intestine is
short and straight. The emu is practically identical with the
OL
Koh
..
17
!
I identify it as
1 PARKER terms it extensor metacarpi radialis brevis.
above.
2 Flexor carpi radialis of PARKER.
506
STRUCTURE AND CLASSIFICATION OF BIRDS
cassowary, but the duodenal loop was strong, longer, and
narrower. It is interesting to find from MITCHELL’s paper
that the intestine of Rhea is somewhat intermediate between
that of Struthio and that of Casuarius. “The anterior portion
resembled Casuarius ; the rectum had an expansion recalling
that in the ostrich, but much less strongly marked.
The following table contains measurements of the ali-
mentary tract 1 in the Struthiones :-

Small Int.
Large Iut.
Cec.
..
-
.
..
-
-
In. Ft. In.
Rhea macrorhyncha o
12
Ft.
i 41,1 9
2. 9
Rhea alincricaria
.
OG GOTHA IA
govo do com
oHHH
2
4,
(young)
Struthio cainelus .
6,
2 8, 2 11
2 103
.
.
Gato to
7
8,
o
2
.
y
2,
.
e de todos
-
#
A W
co co
.
.
#
Casuarius uriappendiculatus
Beccarii
picticollis a
Benzetto 3 .
Apteryx australis
, Owerri
Dromeus Nova Hollandic
Casuarius biccruiculatus
*
o B C A W
All the Struthiones have cæca, which are especially deve-
loped in the ostrich, where they have been described by Sir
EVERARD HOME as well as by GADOW. Apart from their
length and structure the most remarkable fact about them
is that, in contradistinction to what we find in other birds,
they are inserted by a common orifice.
These cæca dwindle gradually in diameter towards the
tip, and are provided internally with a spiral valve of about
twenty turns. I have attempted to compare these cæca with
those of the Martineta tinamou (see p. 488). In the latter
bird the cæca are furnished with numerous short diverticula,
| E. REMOUCHAMPS, 'Sur la Glande Gastrique du Nandou,' Bull. Ac. Belg. 1.
(1880), p. 114.
STRUTHIONES
507
.
.
which are the outward expression of a reticulate internal
structure, like a ruminant's stomach. Towards the extremity
of the cæcum the folds cease to be so definitely arranged in
a network, and some to present an indication of a spiral dis-
position. Rhea has also very large cæca, and there are
traces of the spiral valve of the ostrich. The cæca of the
cassowaries and the emu, as will be seen from the table of
measurement, are very much smaller than those of the
ostrich and Rhea. GADOW mentions an obscure formation of


FIG. 236.—THE SAME, FROM BEHIND.
Fig. 235.-SYRINX OF Apteryx
Mantelli. FRONT VIEW.
(ATTER FORBES.)
0.00, in this and following
figs., tracheal rings.
an internal network by the presence of folds which may be
compared with the structure of the cæca of Calodromas,
already referred to. The cæca of Apteryx are long and nar-
row, like those of the tinamous (excluding Calodromas).
Struthio has the most remarkable liver of all the Stru-
thiones. The two lobes are intimately fused into one heart-
shaped lobe. There is an indication of a spigelian lobe, as
with other Struthiones, and the single bile duct (there is no
gall bladder) opens, exceptionally, only 4 cm. from the
pylorus. Rhea has, as a rule, no gall bladder, but GADOW
found traces of one in a specimen dissected. This occurred
(see figs. 19, 20, p. 34) both in Rh. Darwini and Rh. americana.
Casuarius and Dromaus have a well-developed gall bladder,
{
LO
UU
508
STRUCTURE AND CLASSIFICATION OF BIRDS
and MITCHELL noted in the former genus that the gall
duct and the pancreatic duct opened into a distinct diverticu-
lum of the duodenum.

.
YET
OS
Puriniului
-
WW
WIL!
O
ORA
DPD
1
f
.
10
PYR
TERESSE
.
.
A
LOW
RES
FIG. 237.-SYRINX OF Rhea americana. FRONT VIEW. (AFTER FORBES.)
In Apterys there is a gall bladder.
The chief source of information about the windpipe and

TH
SU
MHURS
WWW
IETE
Fig. 238.—THE SAME, FROM BEHIND.
syrinx of the Struthionidæ is contained in a memoir by
FORBES.' These birds, as a rule, possess no specially modified
1. On the . . . . Trachea in the Ratite Birds,' P. Z. S. 1881, p. 778.
STRUTHIONES
509
syrinx, a statement, however, which does not, as was first
shown by ALIX,' apply to Rhea. In that bird (see woodcut,

UNA
/
.
S
.
SY
.
mm
NA
.
re
2
.
.
w
:.
Fig. 239.-SYRINX or Casuarius galeatus. FRONT VIEW. (AFTER FORBES.)

ti
ur
...
AINUKAI
WIRA
12
WO
>
.
1
FIG. 240.--THE SAME, FROM BEHIND.
figs. 237, 238) there is not merely a pair of intrinsic muscles, 2
U
:Bull. Soc. Phil. 1874, p. 38.
: ? First noted, apparently, by PARKER in Tr. Z. S. vol. v. p. 238, foot note..
510
STRUCTURE AND CLASSIFICATION OF BIRIS
but some considerable modification of the last tracheal and
early bronchial rings. The last four tracheal rings are
soldered together to form a cartilaginous box, which behind
and in front shows no lines of demarcation between the
several rings of which it is composed. There is a membrana

SEE
Setler
LISUS
ON
TA
e
.
2.
PONU
WA
INSIR
VCU
.
SU
WA
.
SW
YS
NIC
lib
OR
!TY.
ha
WAY.
.
WIE
STO
li
ti
KA
MO
Sisters
2
SY
w
<
TE
M
62
.
II
NA
PY
IV.
RU
MAU
P
/
21 JA
YA
9
ZII
Pathan
VA
CZ
.
Usin
at 10a
DU
C
V
1
09
.
var
Wilt
Star
:.
WW
...
.
--.:
ciliu
.
D
.
IFA
.
S
11
IS
San
OX
1
w
KINK
29"
AN
CASA
.
.
role
!
.
YO
Who TTT
SA
.
.
YZ
PY
ES
SA
hod
1
.
GE
WOW
VIRU
SORT
2.
12
VAS
1
WAONY:
RA
.
Se
Cir
278
V
Tersant
t
CHA
RA
VW
*
DICE
AYES
NO
I
OT
..
r.
WA
'
TES
AVIIK
BASS
CA
Kui
SOOV
SA
FIG. 241.–TRACHEAL POUCH OF EMU CUT OPEN (ATTER MURIE).
Tr, Tp!, the pouch ; ap, opening into trachea ; c.d.s, prolongation of upper end of pouch ;
fo, ', fibrous glands.
tympaniformis and a pessulus ; the first three or four
bronchial semi-rings are different from those which follow.
The remaining Ratitæ have no distinct syrinx. In Struthio,
for example (see figs. 43, 44, p. 64), although there is a mem-
brana tympaniformis completing the bronchi internally, there
is neither pessulus nor intrinsic muscles. The syrinx of
Apteryx is about on the same level. Casuarius is rather
2
LULU
STRUTHIONES
511
different. The last few tracheal rings are incomplete
posteriorly; the space left between them is continuous with
a membrana tympaniformis. There is no pessulus or
intrinsic musculature; in the division of the last tracheal
rings there is a suggestion, faint perhaps, of the tracheal
syrinx. Dromæus, as might be imagined, closely resembles
Casuarius. It has, however, a peculiarity which has been
fully gone into by MURIE, who quotes the pre-existing
literature upon the matter. In front of the trachea some
way down the neck a certain number of the tracheal rings
are deficient in front; and the lining membrane of the tube
here projects as a sac, which can be inflated, and has, no
doubt, something to do with the drumming voice of the
bird. The accompanying illustration shows this peculiarity,
which is not met with in the cassowary.2
As to osteology, in Rhea (fig. 77, p. 140) the vomer tends
to be bifurcate posteriorly where it is much widened out, and
articulates both with the palatines and the pterygoids. The
palatines are posteriorly flat and fenestrated. The maxillo-
palatines are thin plates which meet the anterior bifurcation
of the vomer. The descending process of each lacrymal
has a large foramen, the presence of which led R. O. CUNNING-
HAM to distinguish Rh. Darwini from Rh. americana, where
the foramen is simply a notch. GADOW, however, showed
that the question of notch or foramen is simply individual
variability, and I am in a position to assert the same of Rh.
macrorhyncha. The existence of a complete descending
process of the nasal has been denied. PARKER, however,
has figured an ascending pillar of bone from the maxillary,
and in a specimen of Rh, macrorhyncha this was joined by a
suture to the anterior margin of the lacrymal. It has, it is
true, no connection with the premaxillary part of the nasal ;
but this can scarcely interfere with a comparison of the
T'On the Tracheal Pouch of the Emu,' P. Z. S. 1867, p. 405.
? For the lungs and air sacs of Struthiones see ante, p. 495. Those of
Rhea have been described by W. N. PARKER, “Note on the Respiratory!Organs
of Rhea,' P. Z. S. 1883, p. 141 ; of Dromæus by Malm, Om Luftrör-säcken,'
&c., Öfv. K. Vet. Al. Förh. 1880, p. 33.
3 PANDER and D'Alton, Die Skelete der straussartigen Vögel. Bonn, 1827.
512
STRUCTURE AND CLASSIFICATION OF BIRDS
bone to the outer part of a nasal and to the naso-maxillary
of the Dinornithidæ (see below).
There is a well-developed, though thin and curved,
ectethmoid lamina, which joins the maxillo-palatine below
and the descending process of the lacrymal above. This has
been also stated to be absent.
Rhea has seventeen cervical vertebra. The atlas is
notched, as in Struthio, but not so widely. In the shoulder
girdle the procoracoid is short, but is continued down to the
articulations of the coracoid by the membrana coracoidea,
of which, in a specimen of Rhea macrorhyncha before me, a
се

16
.
th
VITI
.
II
#
.-
DO
www
HAM
.
ww.
S
ww.
A
*
www
.-
JUUNI
•
w
.
.
he
L
.
TA
.
E21
re
.
-
SL
.
..
www
www
**
.
-
AWA
man
ant
8
.
.
-
www
A
+
-
-
1
SA
A
V
Fig. 242.- STERNUM OF Rhea (AFTER MIVART).
cc, coracoid grooves; ca, anterior lateral process ; f, keel (?); l.x, posterior lateral process.
portion is ossified as a thin spicule of bone shutting in the
foramen coracoideum. The sternum (see fig. 242) has a
median ventral prominence and two lateral thin rings of the
bone, which may be indications of foramina. Three (some-
times four) pairs of ribs reach the sternum. The pelvis
(fig. 243) has a small pectineal process. The pubes join
the ischia posteriorly, and anteriorly an interohturator pro-
cess, of which there are faint indications in Struthio, unite
the two bones. Posteriorly the ilia are attached to the
ischia.
STRUTHIONES
513
The structure of the skull of the emul is not widely
different from that of the skull of Rhea. The vomer is
widely bifurcate behind, where it articulates both with
pterygoids and palatines. The basipterygoids articulate
with the pterygoids at the extreme posterior end of the

iz
.
WAND
MIN
Willia!
.
.
.
Un
A
sowie
Fig. 243.-PELVIS OF Rhea (AFTER MIVART).
il, ilium ; lp, pectineal process; at, antitrochanteric process; st, supratrochanteric process;
ps, interobturator process ; i, ischium ; p, pubis.
latter, instead of nearly halfway along them, as in other
birds. The maxillo-palatines are hollow swollen plates,
which unite with the vomer and premaxillaries, but come
apart in the dried skull. The descending process of the
lacrymal has a foramen, as in Rhea. It joins the thin
lamina of the ectethmoid. The descending process of the
1 W. K. PARKER, On the Structure and Development of the Skull in the
Ostrich Tribe,' Phil. Trans. 1868, p. 113.
LL
514
STRUCTURE AND CLASSIFICATION OF BIRDS
nasal is only represented in the specimen before me by a
minute pointed bit of bone attached above to a point cor-
responding to that whence the "naso-maxillary' arises in
Rhea.
Dromaus has twenty cervical vertebre. The atlas is

G
..
.
.
w
.
RA
wwww
.
WP
w
www.
ww.
w
w
.
-
Map
NO
E
SK
VO
7
w
mm
ERT
.
GS
ST
.
6
.
Will
.
wauli
9
.
.
M
.
U2
DV
TIZ
","AVA
.
/
<
2
.
.
Fig. 244.—SKULL OF EMU (AFTER HUXLEY).
Pmx, premaxilla ; Mxp, maxillo-palatine; Vo, vomer ; Pi, palatine ; Pl, pterygoid ;
*, basipterygoid process.
notched, very nearly perforated (fig. 66, p. 118). The procora-
coid is not quite so well developed as in Rhea, but there
are a pair of rudimentary clavicles.
The sternum (fig. 74, p. 129) 'much resembles that of
Rhea ;' it is not notched and is rather pointed at its
extremity. Three or four ribs reach it.
STRUTHIONES
515
The pelvis (fig. 245) has the pubes and ischia quite free
posteriorly in the dry skeleton; but they are united by
cartilage, as in the latter with the ilium. The interobturator
process is present, and shuts off an anterior portion of the
obturator foramen.
The skull of Casuarius 1 is very like that of Dromcus.
The number of cervical verterbre in Casuarius varies
from eighteen to nineteen. In the atlas the indication of the
m

Ti AW
12
i
SEO
De
AC
E
LIFE
Pro
M
BES
gungo
TV
ISSN
.
MWIS
a
.
VI
!
Milli
MUNKKI
.!
2012
.
DIA
X2
TATUTU
.
.
ITIE
.
.
.
when
www
.
..
.
.
V
**
...
.
40liti,
IDI
closing of the notch for the odontoid process may be com-
pleted, as is shown in the cut (fig. 68, p. 118). The shoulder
girdle is very like that of the emu, possessing also rudimen-
tary clavicles. The membrana coracoidea may, however,
be ossified, and there are two foramina. One of these lies
between the membrana coracoidea and the coracoid, and
is therefore apparently the homologue of the foramen in
W. H. Flower, “On the Skeleton of the Australian Cassowary,' P. Z. S.
1871, p. 32.
L L 2
516
STRUCTURE AND CLASSIFICATION OF BIRDS
Dromæus; the other is smaller and further back in the
substance of the coracoid.
The sternum (fig. 246) is an exaggeration of that of
Dromæus, being longer and more pointed posteriorly. Four
or five ribs articulate with it.
The pelvis too, though very like that of the emu, is (fig.
247) an advance upon it in structure. There may be (C.

DUNUDE
VOIRIWA
DINIMNY
www
lo mal for invidundrattuale
niiUNIRII
WWWYWWRONO3
WIDIH.
umiinin
...
!
VI
::.
COM
AN
WWWWWWWWWWW
BURUNDINUM
.
AWS
Ayokohore Pentholimpiados
.
SUTARTY
QUOMOWWIIHIIIIIIIIIIII
WM
litib.
MWWWWWWWWWWWW
WWWWWWWWWWW
JWWWWWMMWM
VA
i
.
M
VM
VN
N
LOVINI
WIIHOIU
VUURIN
W
M
.2
Fig. 246.-STERNUM OF CASSOWARY (AFTER MIVART).
C, coracoid groove; mx, posterior end. Other letters as in fig. 242.
galeatus) or may not be an osseous union between pubis
and ischium and between ischium and ilium.
The ostrich skull is rather unlike that of the other two.
The vomer is very short and does extend back as far as
the articulation of the palatines and pterygoids. The latter
bones articulate not only with the basipterygoid processes
but with the basisphenoid; they bear off the palatines, which
T.W. GRUBER, ' Ueber das Thränenbein der straussartigen Vögel,' &c., Bull.
Ac. Sci. St.-Pétersb. 1855, p. 161. It varies somewhat in length according to
FÜRBRINGER, and was found in one case to be not unlike the vomer of an
ægithognathous bird.
STRUTHIONES
517
run forward in a straight course. The maxillo-palatines
articulate with the vomer.
The axial skeleton has been described in the greatest
detail by MIVART.1
There are twenty cervical vertebre, and then five which
have ribs articulating with the sternum. The atlas is more
simply ring-like than in other birds; it has a very wide notch

*
s
how
at
11
It
.
MIS
M
Gm
:
:
VI
.
/
NIEZAK
JITHMONTER
VOLUME
VIAWM
.
20
.
.
.
MA
AYY
NY
.
2
Ukoliko
NINE
TO
}
BEBERANI
.
.
.
.
r
.
.
.
Nist
Sa-
ZIO
Fig. 247.-PELVIS OF CASSOWARY (AFTER MIVART).
pl, pelvic rib. Other letters as in fig. 243.
for the odontoid process of the axis. The catapophyses of
the seventeenth cervical unite.
The sternum has a raised and flattened tract posteriorly,
which may be the equivalent of the keel ; it has two posterior
lateral processes, which extend beyond the median portion of
the bone.
T'On the Axial Skeleton of the Ostrich,' Tr. Z. S. viii. p. 385.
518
STRUCTURE AND CLASSIFICATION OF BIRDS
The pelvis is remarkable for the symphysis of the pubes,
which is shown in the accompanying figure (fig. 250). The
ischia also unite each with its corresponding pubis. There
is a well-developed pectineal process. GARROD 1 and F. DAR-
WIN described a small ossification attached to the front
Рах асу
1
.

(
Alter
SO
.
.
-
*
:_B
M
JHWAY
V
-
-
-
-
AZ
-
.
-
2
DOTARY
1
.
PER
.
42
Đ
S
H
mm
1
.
.
Pali
IS
5,12
-
!
i
.
YARAN
ww.re.
V.
-_-
YO
.
w
1
*
.
WIDTH
VIIIIII
III11
re
OKU
.
P
.
NA
NX
:
.
-7
.
.
.
.hr
UN
.
INI
E
.
..
FIG. 248.-SKULL OF OSTRICH (AFTER HUXLEY).
R, rostrum. Other letters as iu fig. 244.
margin of the pubis which may conceivably be the homologue
of the marsupial bone of the marsupialia.
The skull of Apteryx has been described by OWEN ? as
I'Notes on an Ostrich lately living in the Society's Gardens, P. 2. S. 1872,
p. 356.
2 "On the Apteryx australis,' Trans. Z. S. ii. p. 57, and iii. p. 277.
STRUTHIONES
519
regards its adult structure, and the development has been
lately treated of by T. J. PARKER.)
Apart from the very elongated anterior part of the skull
mac ca

.
IN
V
ON
VIIb WWW
W
brom
om
STA
th
un
ley
vi
m
usic
loot
Fig. 249.-STERNUM OF OSTRICH (AFTER MIVART).
LETTERS AS IN FIG. 74.
the characteristics are those of the struthious birds generally.
The Y-shaped posterior end of the vomer bears off from

ac
II
nili
Wi
OM
WWWA
P
12.
AM
NL
ARA
-
NUNTA
TAHUN
"
TI
ii...
W
CASTEL
KAK
Rp
-
DIN.
-
UNMU
WATERS
R SOS
SA
Si!
ROSET.
.2
2
.
2.
1
*OR.
2
II.
TULUNUL!!
18
IV.
..
.
!
PRI
VVS2
.
:
..
.
.
YA
2
10
,
IAVI
AI11
.
.
UP
CAT
.
.
strani
IN
ws
27
ht
.
2:
11111111
Bima
21/
WIDUUDIIDIINI
7UIIHII
W
IIIINNN
FIG. 250.—PELVIS OF OSTRICH (AFTER MIVART).
sy, symphysis pubis. Other letters as in fig. 243.
articulation with the rostrum the palatines and pterygoids.
The basipterygoid processes are large. As in all other
l'Observations on the Anatomy and Development of Apteryx,' Phil. Tran
clxxxii. (1891), p. 25.
520
STRUCTURE AND CLASSIFICATION OF BIRDS
struthious birds, with the exception of the adult cassowary
and the Dinornithidæ, the ossified ethmoid appears on the
dorsal surface of the skull between the nasals. In the adult
the sutures disappear, and the bones are so firmly united
that the quadrate and the columella are the only movable
bones in the skull. The quadrate has a two-headed otic
process, differing so far from other struthious birds and
agreeing with the Carinata.
PARKER's statements as to this matter are opposed to
those of FÜRBRINGER in the table of differential characters
which he gives in his great work. The vertebral column is
described by the authors already quoted as well as by
MIVART. There are sixteen cervical vertebra, and four ribs.
articulate with the sternum. The atlas is either perforated
or only notched by the odontoid process, and it is imperfectly
joined above, not always, but in many cases, at the summit
of the neural arch. The tenth and eleventh vertebræ have.
sometimes a ventral hypapophysial canal, as in Herodiones.
MIVART found this to be the case with A. Oweni. I found
the catapophyses to approach each other very closely in
that species and in A. australis, but not to fuse.
The sternum is somewhat variable in form. Occasionally
the posterior lateral processes exceed the middle process in
length; sometimes they are less or subequal. As a rule the
sternum appears to be broader than long, but this is not
invariably the case. The varying proportions of the sternum
and the lengths of its several processes seem to offer cha-
racters diagnostic of the species. In two specimens of A.
Bulleri PARKER found a 'low ridge nearly as well marked as
the vestigial keel of String ops. The shoulder girdle, like the
sternum, is subject to great individual variation. The relative
lengths of the scapula and coracoid vary; the curve of the
scapula varies, but it is in the coracoid that the most inte-
resting variations occur. The coracoid notch, converted by a
ligament into a foramen, but being in the embryo a distinct
foramen in the cartilage, is sometimes absent, its place being
1. On the Axial Skeleton of the Struthionidæ,' Trans. Z. S. vol. x. p. 1.
See also ALLIS, 'On the Skeleton of the Apteryx,' J. Linn. Soc. 1873, p. 523..
STRUTHIONES
521
indicated by a thinning of the bone. The rudiments of.
tuberosities for the attachment of the missing furcula are
often fairly evident. The coraco-scapular angle oscillated
between 150 and 122. There is a supracoracoid foramen.
In the pelvis there is no fusion between ilium, ischium,
and pubis. The pectineal process is long and appears to be
ossified equally by pubis and ilium. In the skeleton of the
adult foot two of the tarsals are present as free bones not
fused with either the tibia or the metatarsus; these are,
according to T. J. PARKER, two centralia.
The bones of the wing in the struthious birds are espe-
cially reduced in the emu, cassowary, and Apteryx.
The wing of the adult emu (Dromaus ater) has been
figured and described by PARKER. There is no trace of a
separate carpus either in young or adult. In a six-weeks-old
chick the first metacarpal is half the length of the second,
but in the adult it is reduced to a small prominence not a
third of its length. There is no trace of a third metacarpal.
The single finger (the index) has three phalanges and a long
strong claw. The wings of an adult are about the size of
those of a jay or a bower bird ; in the young chick, with legs
the size of those of a turkey, the wings are no longer than a
wren’s.'
In Apteryx the wing is in some respects further reduced
than that of the emu; in others less so. In the adult A.
australis (T. J. PARKER) there are no distinct carpals, but a
broad flattened carpo-metacarpus, with traces of being com-
posed of three metacarpals. There are sometimes two and
sometimes three phalanges—the last clawed--to the single
finger (index); where one is atrophied it is the second. In
A. Oweni there appears to be invariably a distinct radiale ;
the third metacarpal is more distinct than in the last species,
and in one case was entirely free. The clawed index has
two or three phalanges. The single example of A. Haasti
which PARKER examined had an ulnare as well as a radiale
in the carpus, a fairly distinct metacarpale III., and three
phalanges to the index.
In A. Bulleri the manus shows much greater variations ;
522
IL
STRUCTURE AND CLASSIFICATION OF BIRDS
lu
in one specimen a radiale is present in the carpus, in another
a bone which appears to represent radiale and distal carpals;
this specimen had a free third metacarpal. In two other
instances there is a carpo-metacarpus, as in A. australis.
There are two or three phalanges and, as always, a claw to
the index.
The development of the manus of Apteryx shows plainly
what is also apparent from its adult structure, that it is in a
condition of degeneration. Traces of three distal carpals, as
well as of radiale and ulnare, are visible; all the metacarpals
are distinct, the third being as long as the second and having
a rudimentary phalanx.
The Æpyornithidæ, containing the type genus Æpyornis
and a recently established new genus, Mullerornis, was for
some time only known by the subfossil egg and by the
bones of the hind limb. More recently Messrs. MILNE-
EDWARDS and GRANDIDIER, and more recently again Mr.
C. W. ANDREWS, have described other parts of the skeleton,
so that now, though there are still many lacunæ, we have a
fair knowledge of several important parts of the skeleton.
This family is limited to Madagascar, where its remains have
been found chiefly in marshes.
The skull is only incompletely known-the palate, for
instance, so important in determining its affinities, is quite
unknown-being only represented by what is little more
than a calvaria, and by an imperfect mandible. The occipital
condyle is pedunculate, as in the moas. The frontal region
of the skull is covered by many pits, which are arranged in
a fairly regular fashion ; it is suggested that these may be
the marks of the inplantation of feathers, of which, therefore,
the Æpyornis may have possessed a frontal crest—a feature
which has also been observed in certain moas. There are
also, as in the moas, a prominent basi-temporal platform,
1. Observations sur les Apyornis de Madagascar,' Comptes Rend. cxviii.
1894, p. 122 ; Sur les Ossements d'Oiseaux,' &c., Bull. Mus. Nat. Hist. 1895,
p. 9; “On the Skull, Sternum, and Shoulder Girdle of Æpyornis,' Ibis (7), ii.
p. 376 ; 'On some Remains of Æpyornuis in the British Museum,' P. Z. S. 1894,
p. 108.
STRUTHIONES
523
an open Eustachian groove, and a similar structure of the
articular facet for the quadrate.
The sternum is singular by its extraordinary breadth
and great shortness; the length in the middle line is only
one-fifth of the greatest breadth. The hinder border is not
notched, but forms a 'gently concave curve. The antero-
lateral processes are stout. There is, of course, no keel.
The coraco-scapula is typically ratite, the angle between

.
.
.
22
4
.
.
*
"
4
.
:
D
.
.
M
.
..
.
.
.
PUNT
NRWSZNICATEN
w
AVA
YA
WEEAWAY
OXOX.NA
.
.
.
**.:
..
.
.
.
.
WC
.
..
1
.
mikor
2
SMAS
!
.
LISAN.
2. 11. ***MINIMALI
1,
M
33
U
E
Onth
..
WO-
D
SV
YO
.
.
.
.
..
.
.
.
".
17
VIVI
.
.
.
.
**
"
*
*
R
32
BV
VY
VA
**
XC:
*
.
BUS
V
R
1
.
2.
..
1. UPA
CA
.
Xey
no
RO9
QUtu21
st
FIG. 251.--SHOULDER GIRDLE OF Æpyornis (AFTER ANDREWS).
sc, scapula; pc, procoracoid ; f.spc, foramen supracoracoideum ; gl. glenoid cavity.
the two being very slight. As will be seen from the figure,
it most resembles that of Casuarius. The bird had a
rudimentary humerus.
Dinornithidæ.—This family consists of a number of
genera, all New Zealand in habitat; their remains are so
abundant in various parts of the country that they must
have existed in countless numbers. That there should have
10
524
STRUCTURE AND CLASSIFICATION OF BIRDS
been within so limited an area at least twenty-five distinct
species is explained by Captain Hutton by the view that at
one time the two islands of New Zealand were divided up into
a greater number--an archipelago, in fact, the result of this
being what we now see among the cassowaries, where each
of the islands inhabited by them has its own peculiar species,
isolation, indeed, permitting of the specialisation. All the
moas, however, became extinct at a period not less than
three or four hundred years ago. T. J. PARKER,' whose
work on the cranial osteology of the group is the most
recent, allows the genera Dinornis, Pachyornis, Mesopteryx,
Anomalopteryx, Emeus, and probably Megalapteryx, dis-
tributed among three subfamilies. The moas—a general
term applied to all these genera—were birds of fair, often
large, size. The smaller species ranged from 21 to 4 feet in
height; the largest were at least thirteen feet high.
The skull of the moas had a short and wide beak. The
occipital condyle is remarkable on account of its more or
less pedunculate character,' a circumstance which is of
importance in considering the relationship to the moas of
the Madagascar Æpyornis (see p. 522).
The orbit is smaller than in other struthious birds. The
nasals are peculiar in that they meet behind above the
ethmoid, so that no part of the latter bone appears on the
upper surface of the skull. It is only in the adult cassowary
among recent struthious birds that the ethmoid is entirely
hidden on a superficial view, a state of affairs which is
brought about by the development of the crest, and does
not exist in the young bird. The palate is like that of the
emu and cassowary, but is most like that of Apteryx.
The nasal bone is furnished with a slender maxillary
process, or, as in emus, there is a corresponding bone
separately ossified. The lacrymal is firmly ankylosed to
frontal; its descending process joins ectethmoid. T. J.
PARKER has figured and described a peculiar thin scroll-like
bone which appears on a lateral view of the skull and pro-
I'On the Cranial Osteology, Classification, and Phylogeny of the Dinorni-
thidæ,' Ir. Z. S. xiii. p. 373.
STRUTHIONES
525
jects beyond the anterior margin of the maxillo-nasal ; this
he has termed the alinasal.
The number of cervical vertebræ is large, at any rate in
Anomalopteryx parva, the only species in which they are
all without doubt preserved. There are in this bird twenty-
one. The sternum is longish and rather narrow in Anomalo-
pteryx casuarina ; it is short and broad in Dinornis maximus.
In all it has a pair of lateral notches strongly marked; the
lateral processes are strongly divergent. There is also a
median posterior notch.
The pectoral girdle is but little known, and appears
sometimes to have been completely absent.
In the pelvis the bones are separate and the pectineal
process but little marked.
That the feathers have large aftershafts, like the emu,
&c., was first discovered by the late Mr. DALLAS.) Sir R.
OWEN has figured the ossified rings of the trachea ; but they
present no special features of interest.
As to their relationships with other ratites, T.J. PARKER
is of opinion that they form, together with the Apteryx and
cassowaries, a definite branch of the struthious tree, as in
the annexed diagram, which is from his paper. FÜRBRINGER
comes to conclusions which are not greatly different. The
relations of the Dinornithidæ to Struthio and Rhea are
'ganz entfernt,' to Dromaus and Casuarius "fern, but
to Apteryx ' nahe.'
There is no doubt that Struthio is removed far from the
Dinornithidæ, as well as from other ratites, by the structure
of its palate, which diverges much. But it not clear that
Rhea is so remote; the existence of an apparent homologue
of the maxillo-nasal bone, to which I have referred in the
description of the skull of Rhea, is a point of somewhat
striking likeness to Emeus, while the conformation of the
skull generally in Rhea does not seem to divide it very
deeply from Casuarius, &c. Though no doubt T.J. PARKER
is right in directing attention to the special resemblances in
the skulls of Apteryx and the Dinornithidæ, it must not be
1. On the Feathers of Dinornis robustus,' OWEN, P. Z. S. 1865, p. 265.
526
STRUCTURE AND CLASSIFICATION OF BIRDS
forgotten that Dinornis, like other ratites, except Apteryx,
has a single head to the quadrate. In the characters of the
pelvis Dinornis is near to Apteryx and the Casuariidæ and
remote from Rhea (as well as from Struthio). The large
aftershaft allies it to the Casuariidæ. NATHUSIUS has
commented upon the practical identity in egg-shell structure
which Rhea shows to Dinornis, a likeness which impressed
him so greatly that he proposed to place them in the same
genus. A considerable number of the special relations
between Apteryx and the Dinornithidæ, upon which FüR-
BRINGER writes, such as failing pneumaticity, absence of
clavicle, mutual distance between coracoids, and even the
form of the sternum, may largely depend upon the loss of
flight, which is more complete in these birds than in the
ostrich, for example. In no less than three footnotes
FÜRBRINGER comments upon the supposed absence of
uncinate processes to the ribs of the Dinornithidæ ; but
this difference from other ratites does not exist, as T. J.
PARKER has definitely asserted their presence. It is signi-
ficant that in his tables of differential characters FÜRBRINGER
refers little to those of the fore limb girdle (including
sternum) as distinguishing Dinornithidæ from Rheu. A
detailed account of the pros and cons will be found in the
systematic part of FÜRBRINGER's work, and as regards the
skull in PARKER'S paper already referred to.
The Struthiones have been often held to be more primitive
than any of the existing groups of birds.
There are really, however, not a large series of characters
in which they may be fairly said to be more primitive
than some other groups, and most of these are shared by
some others.
The form of the palate and the single-headed quadrate
appears to be a low character; but the former is shared
with the tinamous, the latter with some other groups. The
incompleteness of the fusion of the cranial bones may be
looked at in the same way; but the penguin is on the same
level as the Struthiones. The absence of any fusion distally
between the bones of the pelvis in Apteryx and Dinornis is
D.
Apteryx
My
.
.
TV
. ..

Rhea
.
ICHO
MUS
Struthio
NA
Dromaeus
4.
mer
.
This
R
**
r
.
YOA
WAMVU
ni
.
.
WG2735
"
Oy
.
.
2
Carinatae
.
A
VIWANDA
marTXEA
INN
*
W
22
.
S
le
.
.
NU
**
*
FIG. 252.
*
.
rreth
A
G
77
.X
.
X
Dinornis
ht
www
1113
LOGO
101
.
*
.
ht
IN HET
LS
Saudi Arabia
.
NR
.
Dikte
ASS
LAW
Vio
Kri
A
Pachyornis
Mesopteryx Anomalo. V
opteryx
Emeus
A
528
STRUCTURE AND CLASSIFICATION OF BIRDS
dinosaurian ; but the tinamous are like Apteryx in this.
The complete procoracoid of Struthio seems to be an archaic
character, as do the two free centralia in the foot of Apteryx.
As to negative characters, the most important of those that.
are possibly, but not certainly, to be regarded as primitive
appears to be the usual absence of the oil gland.
The long rectum of Struthio is probably an ancient
character ; but whether the absence of a bird-like syrinx in
all ratites except Rhea is a similar feature seems to be
doubtful. The large size of the blood corpuscles in the
ratites is noteworthy in this connection.
The following table gives the principal characters of the
existing genera. From it may be inferred the somewhat
less modified condition of Apteryx and the very isolated
position of Struthio among the members of the group :-

Struthio
Rhea
Dromæus
Casuarius
Apteryx
Aftershaft . : :
Rhomboideus profundus
Lat. dorsi anterior
Lat. dorsi metapal.
Serratus metupat.
Pectoralis abdomi .
Muscle formula of leg
0Otto
oootto
oottt
0Oto+
ooottt
.
ABXY+
BXY+
2
2
Buvo
.
Carolids.
Syrinx .
Large intestine
Cueca .
Manus.
Cervical vertebrce
Atlas . . .
R.
Very long
Long
3 digits
Not long
Long
3 digits
BXY ABXY+ ABXY+
or
L
R.
R.
Not long Not long Short
Short
Short Moderate
1 digit I digit 1 digit
20
18, 19
16
Notched Notched or Notched
perforated
Bones free / Bones free / Bones free
20
17
Pelvis .
.
.
.
. Notched by Notched
| odontoid
. A symphysis Ischia and
pubis; ischia ilia join
join pubes
Clavicles
R.
0
SAURORNITHES
22
GROUP SAURURE
LU
SAURORNITHES
As there is but a single genus, and in all probability but
a single species,' in this group, it is useless to attempt any
formal definitions of family or other characters. I shall
merely give the more important facts in its structure, as I.
have with the foregoing groups. As to external characters,
the Archæopteryc has an anisodactyle foot, like that of the
Passeres. The feet and the digits of the manus have been
stated to have been covered with scales. That scales may have
been present, at least on the foot, is very probable, but there
is not the faintest evidence of their having been there. Of
feathers the remiges and rectrices are plain, while of the
general body feathering there is not so much evidence.
With the exception of a circle of feathers upon the neck.
suggestive of those of the condor, and similar rings of
feathers upon the ankle, it is thought by some that the
Archæopteryx was naked. Most of the restorations, how-
ever, admit a general feathering. The chief criticism to be
offered is the extreme perfection of the remains of such
feathers as are visible in the slab of stone in which the dead
bird was originally imbedded. This being the case, the
apparent absence of feathers over the general body surface
gains more weight. That they may have been present and
of the nature of down feathers is believed by reason of
certain faint indications of something to round the contours
of the body; the group of contour feathers upon the leg are
plainly visible even in photographs of the Berlin example.
This example is much better than the specimen in London,
which is the only other skeleton in existence. The rectrices
are quite obvious, a pair to each of the separate vertebræ of
the tail. There appear to have been not fewer than thirty
i It has been argued that specific and cren generic differences exist between
the London and Berlin cxamples,
M M
530
STRUCTURE AND CLASSIFICATION OF BIRDS
1
UUVCU
of these ; FÜRBRINGER places the number between that
figure and forty. Most of the restorations allow thirty-
two or thirty-four. This number is important; it is in
excess of that generally found in living birds, although the
tail itself is not composed of actually more vertebræ.
Among recent birds it is perhaps a significant fact that
the penguins alone have this number. Of remiges seven-
teen appears to have been the number, six or seven
primaries and ten secondaries. No existing bird has
so few primaries, the nearest approach being nearly all the
Anomalogonatæ (and some other birds too), which have ten.
There is some difference of opinion as to how these remiges
were attached to the arm and hand. DAMES, in his elaborate
monograph upon Archceopteryx, puts forward the view that
they were attached to the metacarpal and down to the
claw of digit II. MENZBIER limits the attachment of the
primaries to the basal phalanx of the third, not second
digit. FÜRBRINGER thinks that the greater number of the
primaries were attached to metacarpal III. and the third
finger, only a few being inserted upon the phalanges of
digit II., where the latter is overlapped by the last-mentioned
digit. HURST has adopted the revolutionary view that there
are missing, and probably cartilaginous, digits IV. and V., to
which the primaries were attached. As to the presumed
additional fingers, if they were really present, where did
they articulate ? The entire available space appears to be
taken up with the digits which are already known. In its
primaries Archæopteryx is the very reverse of the penguin,
which it appears to resemble in its rectrices. The excep-
tional number to be found in that bird is not in the least
explained by the conditions observable in Arch@opteryx.
A beak seems to have been absent in Archæopteryx, owing
to the fact that the teeth extend to the end of the jaws.
The vertebral column of this bird has some fifty vertebræ, of
which ten or eleven are reckoned cervical ; the smallness of
the number, which probably belongs to this category, is only
approached among the parrots and the Pico-Passeres and
some of their nearest allies, where, however, thirteen is the
· SAURORNITHES
531
LCU
lowest number, fourteen being more general. This fact
may, however, have some significance, especially when it is
remembered that fourteen is also found in the penguins, and
when the remarks on p. 164 are taken into consideration as to
the possible low position among birds of the Pico-Passeres.
The vertebræ were apparently amphicalous. There are
only two sacral vertebræ, and, as already stated, the tail is
long and composed of a long series of elongated vertebræ, to
each of which a pair of rectrices are attached.
The ribs seem to have had no uncinate processes, but these
may have been present and cartilaginous; another remark-
able feature about them is the fact that they had, as in many
reptiles, but one articulation. There are also a number of
abdominal ribs which might be supposed to be merely the
sternal parts of the vertebral ribs, were it not for the close
approximation of the V-shaped pairs.
The skull is toothed to the very end of the jaws, thus
rendering improbable the presence of a beak. The nostrils
are definitely holorhinal, and are divided into two holes by an
alinasal growth, as in some living birds. Or else the sup-
posed posterior part of the nasals is really the antorbital
space present in so many birds. It does not seem certain
whether in the latter event the nostrils are bounded behind
by the posterior division of the nasal bone or whether, as in
pterodactyles, a process of the maxilla rises up to join the
nasal. The space for the eye, which has a ring of bones
in the sclerotic, is completed below, as in certain parrots,
by a bony arch.
Concerning the sternum we must, I suppose, agree with
HURST, who has observed that nothing is known, though
much has been written.'
The scapula is eminently bird-like, as is the furcula, with
its U-shaped meeting of the two ankylosed bones. The
coracoid is imperfectly known. The large size of the deltoid
crest of the humerus and the apparent absence of the crest
for the insertion of the pectoralis are the two most salient
facts in its structure: the latter fact supports those who
hold that the sternum, if present, must have been small or
120
ULUI
M M2
032
STRUCTURE AND CLASSIFICATION OF BIRDS
cartilaginous. It is usual to consider that the carpus of
Archæopteryx contained but one carpal ; HURST, however,
asserts that there are two, a radiale and an ulnare. As in
· modern birds, Archæopteryx is generally held to have pos-
sessed three fingers, and, again as in modern birds, the second
is the longest. Hurst holds that the bird had five, and
bases his view upon both fact and theory. As to the former
he sees differences in the supposed second and third meta-
carpals in the Berlin and London specimens ; it is possible,
therefore, that the bones are not the same in the two cases;
hence those of the one may be metacarpals four and five. In
the second place he considers that (for reasons which will
be referred to more fully immediately) the bird used its
fingers for grasping purposes, and that those fingers which
were thus used could not have been hampered with feathers
of the stiff kind shown in the fossils as apparently attached
to them; hence there were missing digits to which these
feathers were attached. In support of this he recalls the
young Opisthocomus, which uses the fore limb as a grasping
organ before the remiges are developed, and is unable to do
so afterwards.
In any case the metacarpals of the three digits are mov-
able, and the number of phalanges progressively increases
from two to four.
The pelvis is ornithic and has a perforated acetabulum ;
but the bones, as in no other bird, are not fused but separated
by sutures.
It has been held that the supposed furcula is composed
of two ventrally united prepubes, as in dinosaurs (and ptero-
dactyles ?)
The hind limb is avian, with nothing remarkable about
it.
The Archæopteryx differs from all birds in the following
characters :-
(1) The tail is as long as the body, with a pair of rectrices
fastened to each vertebra.
(2) The cervical vertebræ (nine) arc fewer than in any
other birch,
SAURORSITIES
533
.
S
C.
(3) There are apparently free cervical ribs, and the
thoracic ribs have but one head.
(4) The sternum is absent or weak (?).
(5) There are abdominal ribs.
(6) The number of phalanges to the fingers of the hand
is as in reptiles.
(7) The constituent bones of the pelvis are separate.
(8) There was no beak.
The Archæopteryx also differs from all birds excepting
those specially mentioned in the following characters : -
(1) The jaws are toothed (also Hesperornis, Ichthyornis,
Laopteryx ?).
(2) The ribs have no uncinate processes (so in Chauna,
Palamedea).
(3) The metacarpals are free (also Gastornis).
It is, furthermore, supposed that the bones were not
aërated, no pneumatic foramina having been discovered.
This would militate against flight, and there are other facts
of structure that indicate at most a feeble power of flight.
It must, however, be observed that the series of rectrices was
apparently continued along the sides of the body, and that
the tibiæ seem to have borne strong quill feathers. From
this HURST infers that the Archceopteryx was ‘fitted for
flight, if not for prolonged flight.' But though it has an
'insessorial' foot it seems doubtful whether the attitude
when at rest was not quadrupedal. The heavy head and
neck and the slenderness of the hind limbs would tend to
throw the centre of gravity further forwards than in recent
birds, HURST thinks.?
As an appendix to the present group may be mentioned
the very imperfectly known Laopteryx——not on account of
any definitely ascertained resemblances, but merely by reason
DAMES, * Über drchæopteryx,' Paliont. Abhandl. ii. 1884, is the principal
memoir upon the bird. BAUR, in Zool. Anz. ix. p. 106, has summed up the
literature down to 1886. Since then Hurst and PYECRAFT have written upon
Archcopteryx in Natural Science, vols. y. vi.
534
STRUCTURE AND CLASSIFICATION OF BIRDS
YA
of the fact that it existed at about the same period. Lao-
pteryx priscus is known from a skull fragment from the upper
Jurassic of Wyoming at about the same horizon as the
· Atlantosaurus beds. It was about the size of the heron
(Ardea herodias). The back part alone of the skull has been
found, and the remains show that the head of the quadrate
was undivided, as in ratites (except Apteryx). Close by was
found a single tooth which may or may not have belonged
to it. MARSHconsiders the bird to have been ratite in its
characters.
I'Discovery of a Fossil Bird in the Jurassic of Wyoming,' Annc. Journ.
Sci. xxi. (1881), p. 341.
INDEX
(Extinct genera and species are printed in italics)
ABDIMIA, 78, 95, 419, 425, 427, 429
sphenorhyncha, 65, 423, 424,
425, 428
Aburria, 299 .
carunculata, 294, 297, 299,
300
Acanthisitta, 181
Accipiter, 478, 484
nisus, 478
Aceros, 54, 102, 216, 217, 218, 219,
Anastomus, 5
coromandelicus, 427
lamelligerus, 420
Anomalopteryx, 149, 524
221
nipalensis, 57, 103, 217, 218,
219, 220
actiornis, 419
Æchmophorus, 119, 326, 386, 387,
388, 389, 417, 461
major, 361, 386
Ægialitis, 343
biaticula, 345
Ægialornis, 350
Ægotheles, 231, 234, 236, 237, 241,
242, 243
Aeipetes, 450
Æpyoris, 494, 522, 523, 524
Æx sponsa, 418, 459, 461
Agapornis, 255, 268, 269
Agnopterus, 444
Alca, 141, 360
impennis, 359, 360
torda, 360, 362, 363, 364, 365
Alcedo, 16, 80, 197, 198
bengalensis, SO
ispida, 200
Alctoriris, 379
Ampelis garrulus, 177
cedrorum, 173
Anarhynchus, 5
Anas, 75, 460
boschas, 458
specularis, 458, 459
casuarina, 525
parva, 525
Anous, 147, 350, 351, 353, 354, 356 .
stolidus, 378
Anser albifrons, 459
cinereus, 460
indicus, 459, 465
Anseranas, 456
melanoleucus, 60, 463
Anthornis melanura, 177
Anthraceros malayanus, 222
| Anthropoides, 368
stanleyanus, 369
Antrostomus, 234, 242
vociferus, 231
Apatornis, 469, 470, 471
celer, 469
Aphanapteryx, 330
Broecki, 330
Aphriza virgata, 338
Aprosmictus, 260, 268, 269
erythropterus, 262
Aptenodytes, 30, 156, 396, 398, 399,400
longirostris, 398.
Apteryx, 12, 39, 40, 45, 47, 49, 60, 72,
73, 75, 76, 78, 80, 81, 82,
101, 112, 113, 116, 121, 122,
123, 127, 132, 135, 136, 137.
148, 151, 152, 153, 155, 161,
337, 384, 471, 492, 494, 495,
496, 497, 498, 499, 504, 507,
508, 510, 518,519,521, 524,
525, 526, 527, 528, 534
australis, 49, 496, 505, 506,
520, 521, 522
Bulleri, 496, 504, 505, 520
536
STRUCTURE AND CLASSIFICATION OF BIRDS
Apteryx Haasti, 496, 521 . ' BALENICEPS, 62, 63, 419, 420, 432,
Mantelli, 100, 496
433, 434
Oweni, 496, 506, 520, 521
rex, 433
Aptornis, 288, 378, 379, 380, 382 | Balearica, 95, 366, 368, 369, 377
defossor, 378
chrysopelargus, 96
otidiforinis, 378
pavonina, 366, 367, 368, 369
Aquila, 476
regulorum, 367, 368 ( = B.
imperialis, 474
chrysopelargus)
nævioides, 477
Baptornis, 471
Ara ambigua, 262, 264
Barita destructor, 177
ararauna, 29, 262
Baryphthengus, 210
chloroptera, 261
Batrachostomus, 231, 232, 235, 236,
Leari, 257
242
militaris, 257, 264
Baza, 475
Aramides, 322, 323, 324, 327, 331, 369! Bernicla brenta, 57, 468
cayennensis, 321, 322
canadensis, 458, 459, 461, 465
Aramus, 366, 367, 368
jubata, 459
scolopaceus, 367
leucopsis, 466
Arboricola, 137, 375
rubidiceps, 55
torqueola, 293
Biziura, 464, 466, 467
Archæopteryx, 7, 17, 21, 111, 112, 113,
lobata, 116, 134, 406, 458,
114, 115, 119, 120, 123, 125, 133,
459, 461, 462, 463, 404,
151, 154, 155, 157, 159, 160, 161,
.: 466, 468
164, 165, 469, 529, 530, 531, 532 Bolborhynchus, 259, 260, 268, 270
Archibuteo, 476
Botaurus, 430, 431
Ardea, 422, 432
stellaris, 57, 430, 431
bubulcus, 432
Brachypteracias, 205
cinerea, 103, 431, 432, 412 Brachyrhamphus, 359, 363
cocoi, 429, 430
• marmoratus, 359,
comata, 432
361, 362, 365
egretta, 430
Brontornis, 384
garzetta, 430
Brotogerys, 269, 270
goliath, 430, 431
tirica, 254, 262
herodias, 534
tovi, 262
ludoviciana, 431
Bubo, 247, 248, 250, 251, 252
minuta, 432
ascalaphus, 245
purpurea, 430, 4:31
hengalensis, 249, 250
sumatrana, 430, 431
capensis, 240
Ardetta, 430
ignavus, 246
exilis, 430, 431
inaculosus, 245
involucris, 4.30, 4:31
maximus, 97
Argillornis, 419
virginianus, 246
Argus, 290
Bucco maculatus, 188, 189
giganteus, 27, 292, 293
Bi.ceros, 17, 55, 101, 215, 216, 218
Asio, 252
atratus, 216, 217. See also
otus, 99, 244, 245, 246, 289.
Sphagolobus atratus
See also Otus vulgaris
bicornis, 216, 219, 221. See
Astur, 75
also Dichoceros bicornis
approximans, 474
conrexus, 215
Novæ Hollandiæ, 478
coronatus, 216, 219
tibialis, 475
elatus, 216, 217. See also
Asturina, 476
Ceratogymna elata
Natteri, 478
Tunatus, 221
Atelornis, 205, 208
malabaricus, 216
Athene noctua, 245, 246
plicatus, 219. See also Rihy-
passerina, 24.6
tidiceros plicatus
Atrichia, 172, 177, 182, 183
rhinocercs, 101, 219, 221
Attagis, 21, 338, 340, 343, 319
subcylindricus, 216. See
Gavi, 349
also Bycanistes subcylin-
Aulacorhamphus, 190
dricus
INDES
5:37
Bucorvus, 44, 53, 57, 85, 90, 103, 152, · Carpophaga, 25, 306, 308, 311, 312,
207, 215, 216, 218
313
abyssinicus, 215, 216, 217,
latrans, 306, 307, 310
219, 220, 221
wenea, 308
Bulweria, 445, 448
paulina, 307, 309
Burrhinus, 343, 345. Sec also Edi- Casuarius, 12, 28, 81, 82, 85, 123,
cnemus
127, 448, 461, 495, 497,
Buteo, 474, 476
505, 506, 507, 510, 511,
vulgaris, 152, 473
515, 523, 525, 526, 527,
Butorides, 422
528
atricapillus, 429, 430
australis, 497
cyanurus, 430, 431
Beccarii, 506
Bycanistes subcylindricus, 219, 221.
Bennetti, 499, 506
See also Buceros subcylindricus
bicarunculatus, 506
galeatus, 125, 509, 516
picticollis, 500
CACATUA, 52, 254, 255, 256, 257, 258,
uniappendiculatus, 506
260, 262, 268, 269
Cathartes, 79, 145, 382, 383, 479, 481,
cristata, 255, 256, 262
482, 483, 484
Philippinarum, 255
atratus, 74, 481, 484
sulphurea, 53, 254, 262
aura, 474, 483
triton, 255, 262
Centropelma, 386
Caccabis chukar, 293
Centropus, 3, 55, 235, 274, 275, 276,
Cacomantis, 274, 280
279, 281
Caica, 259, 260, 261, 263, 268, 270
ateralbus, 277, 278, 279
melanocephala, 204
phasianus, 279
Calidris, 343
i Centurus striatus, 184, 185
Callalcyon rufa, 198, 199
Ceratogymna elata, 103, 218, 221. Sre
(allipepla, 291, 298
also Buceros elatus
californica, 290, 295, 298, Ceratorhina, 363
300
· monocerata, 361, 302,
squamata, 290
363, 364, 365
Callocephalon, 263, 268
Cereopsis, 466, 468
galeatum, 264
Novä Hollandiæ, 458, 159,
Calodromas, 31, 486, 487, 489, 507
465
elegans, 485, 487, 488, 491 Ceriornis, 291
Calænas, 312, 313
satyra, 293
nicobarica, 306, 310
Temmincki, 293
Calopsitta, 202, 268, 269
. Certhia, 16, 174
Nova Hollandiæ, 254, 264 Ceryle, 198
Calyptomena, 178
alcyon, 199. 200
viridis, 178
amazona, 200
Calyptorhynchus, 259, 260, 268, 269
stellata, 200
Banksii, 255, 256, Chætura, 226
caudacuta, 226, 227, 228
stellatus, 254
rutila, 227
Cancroma, 18, 419, 422, 428, 429, 431,
spinicauda, 226
432
Vauxi, 226, 228
cochlearia, 430, 431, 434
zonaris, 226, 227
Capito, 194
Chalcopelia, 312, 313
Caprimulgus, 3, 234, 235, 236, 237, Chalcophaps, 312
238, 239, 240, 241, 242,
chrysochlora, 308
351
Chalcopsitta, 257, 268
europæus, 235
scintillata, 262
Cariama, 38, 40, 54, 137, 144, 148, Chamæa, 174
149, 161, 165, 241, 249, Chamæpelia, 312, 313
336, 366, 367, 373, 374, · Charadrius, 17, 337, 343, 366
375, 377, 379, 382, 3385,
pluvialis, 338, 341, 344
450, 455
Chauna, 14, 28, 31, 338, 73, 74, 79, 8:5,
cristata, 323, 374
145, 288, 292, 101,-1:52, 154, 155, 533
262
538 · STRUCTURE AND CLASSIFICATION OF BIRDS
6
Qon
VILE
Chauna chavaria, 27, 57, 451, 452, 453, ! Colius, 117, 147, 202
454, 455
castanonotus, 203
derbiana, 35, 85, 92, 451, 452, Columba, 17, 89,133, 152, 311, 312, 313
454, 455
livia, 306, 307
Chen, 467
maculosa, 308
cærulescens, 466, 467
Columbula, 305, 312
Chenalopex jubatus, 459, 465
Colymboides, 390
Chenornis, 419
anglicus, 390
Chionis, 112, 338, 339, 340, 342, 346,
minutus, 390
347, 348, 349, 357, 360, 445, i Colymbus, 86, 92, 134, 386, 390, 391,
468
404, 406, 460
alba, 339, 342, 343, 349
arcticus, 387
minor, 348, 349
glacialis, 386, 387, 388
Chiromachæris180
septentrionalis, 387, 388
Chloephaga magellanica, 146, 459 Conopophaga, 68, 282
Chloronerpes yucatensis, 185, 186 Conurus, 255, 257, 258, 259, 263, 268,
Cholornis, 172
vi 270
Chordeiles, 234, 236, 239, 241, 242
aureus, 257
texensis, 235
cruentatus, 257, 264
virginianus, 239
Petzi, 262
Chrysococcyx, 274, 279, 280
Coxacias, 204, 205, 206, 207, 208,
Chrysæna, 312
209
viridis, 307, 308
garrulus, 17, 205, 206, 237
Chrysotis, 98, 254, 256, 257, 258, 259, / Coracina cephaloptera, 174
260, 261, 262, 269, 270 Coracopsis, 254, 259, 269, 270
Bodin, 257
Barkleyi, 262
collaris, 262
nigra, 351
erythrura, 257
obscura, 351
festiva, 262
Corcorax, 176
Guildingi, 43, 259, 261 Coriphilus, 268
leucocephala, 257, 259 Corvultur albicollis, 176
Levaillanti, 257
Coryus, 137, 141, 174
versicolor, 257
corax, 76
viridigenalis, 257
capellanus, 87
Chunga, 85, 117, 144, 373, 374, 375,
cornix, 175
377, 385, 416, 442
corone, 177
Burmeisteri, 51, 93, 114, 374
frugilegus, 175
Ciconia, 17, 65, 98, 99, 103, 419, 422, Corydon, 178
423
Corythaix, 30, 93, 282, 233, 284, 285,
416
boyciana, 428
albocristata, 282, 283, 28ð
maguari, 428
Buffoni, 283
nigra, 99, 425, 427, 428, 435,
chlorochlamys, 283
437
erythrolophus, 283
Circaetus, 476
porphyriolopha, 282
Circus, 473, 476, 484
persa, 283, 285
eruginosus, 477
Cosmetornis, 242
Gouldi, 473, 477, 478
Coturnix, 287, 291, 298
hudsonianus, 477
communis, 293
maurus, 473, 475
Nova Zelandiæ, 304
Cissopis leveriana, 177
Coua, 275, 278, 281
Cittura, 199, 200
Cracticus cassicus, 175, 177
cyanotis, 198
Crax, 291, 292, 299
Clangula, 463
Alberti, 293
Cnemiornis, 128, 457, 466, 468, 469
Daubentoni, 291, 292, 293
calcitrans, 456, 457
globicera, 57, 293, 299, 300, 301
Coccystes, 274, 280
globulosa, 293
Coccyzus, 274, 276, 278, 280
Sclateri, 291, 293, 299
americanus, 279
Crex, 323, 324, 327
Colaptes mexicanoides, 185
pratensis, 82, 322, 323
INDEX
539
Crossoptilon, 298
Didunculus strigirostris, 308
mantchuricum, 291, 293, ; Didus, 121, 311, 314
300
Dinoriris, 7, 119, 132, 135, 378, 384,
Crotophaga, 69, 235, 236, 272, 275,
498, 524, 526, 527
276, 277, 278, 279, 281
maximus, 525
sulcirostris, 279
robustus, 525
Cryptornis, 222
torosus, 149
Crypturus, 79, 489, 491, 492
Diomedea, 416, 417, 445, 450
obsoletus, 487
anglica, 451
sallæi, 487
exulans, 447, 450
tataupa, 486, 487, 489, 490,
melanophrys, 450
491
Diphyllodes, 174
Cuculus, 17, 235, 274, 277, 278, 279, Diplopterus, 274, 277, 278, 280
280, 281,
nævius, 279
canorus, 273, 276, 279 Dissura, 95, 429
Cursorius, 311, 342, 350
episcopus, 423, 424, 425, 428
Cyanocorax cyanopogon, 177
Dromæus, 120, 123, 134, 490, 491, 495,
Cyanorhamphus, 255, 260, 269, 270
497, 498, 503, 507, 511,
Cyclopsittacus, 267
514, 515, 516, 525, 527,
Cygnus, 462, 466
528
americanus, 464
ater, 521
atratus, 459, 464, 465
Nova Hollandiæ, 506
Bewickii, 460, 464, 465
Dromas, 350
buccinator, 459, 464 465, Dryocopus martius, 185, 186
coscoroba, 464, 465
Dryornis, 384
ferus, 459, 464, 465
Dryotriorchis, 475, 478
immutabilis, 464
spectabilis, 474,475, 478
musicus, 458
nigricollis, 458, 459, 464, 465
olor, 459, 464, 465
ECLECTUS, 260, 262, 268, 269
Cymbirhynchus, 62, 178, 179
polychloros, 118, 262, 264 .
Cymochorea, 446
Ectopistes, 312, 313
Cypseloides fumigatus, 226, 227
Edolius, 173
Cypselus, 17, 75, 80, 86, 98, 226
Elanus, 473, 477
alpinus, 226, 228
Elorius, 356
apus, 228
Elorris, 444
melba, 23, 229
Emeus, 524, 525
crcissus, 149
Enaliorris, 471
DACELO, 140, 197, 198, 199
Entomyza cyanotis, 177
cervina, 200
Eos, 256, 257, 259, 266, 268, 269 .
Gaudichaudi, 197
cardinalis, 260
gigantea, 197, 198, 199, 200
indicus, 262
Dafila acuta, 458, 459
reticulata, 262
Daption capensis, 446
Eremophila, 174
Dasornis londinensis, 498
Erismatura, 464
Dasyptilus Pecqueti, 262
rubida, 458
Dendrochelidon, 226
Erythrænas, 309, 310, 312, 314
Dendrocygna, 465, 468
Erythropus vespertinus, 476
arcuata, 465
Eudocimus albus, 439
autumnalis, 459, 465,467
ruber, 435, 439
Deroptyus, 260, 261, 263, 268
Eudromias, 340, 348
accipitrinus, 258, 262 Eudynamis, 272, 275, 277, 278, 279,
Diaphorapteryč, 330
280
Hawkinsi, 330
orientalis, 273
Dicherocos bicornis, 219. See also Eudyptes, 30, 41, 42, 74, 396, 397, 400
Buceros bicornis
chrysocome, 397, 398, 399.
Dicrurus, 182
chrysolophus, 398
Didunculus, 263, 305, 308, 309, 311, Eudyptula minor, 21
312, 313, 314
Eumomota, 210
.--.-.--
-
-
-
-
5510
OF BIRDS
T
STRUCTURE AND CLASSIFICATION --
-
-
383
Euplocamus, 291
! Fulica leucoptera, 324
albocristatus, 293
Newtoni, 330
Andersoni, 293
prisca, 330
cristatus, 293
Fuligula, 463
erythrophthalmus, 293
ferina, 459
nobilis, 293
rufina, 458, 459, 463
nycthemerus, 293
Fulmarus glacialis, 446
Swinhoii, 293
Furnarius, 143, 182
Vieilloti, 290, 293
Euphema, 268, 269
GALBULA, 213, 214
pulchella, 262
rufoviridis, 213, 214
splendida, 262
Gallinago, 341, 343
Eupodotis, 53, 332, 334
gallinula, 343
arabs, 332
Gallinula chloropus, 322
australis, 332, 333, 334, 335' Gallus, 17, 290, 291, 300
Denhami, 331, 332, 333,
bankiva, 100, 291, 293, 299, 300
334, 335
domesticus, 292
kori, 332, 333
Sonnerati, 29:
Eupsychortyx, 291
Gambetta, 343
Eurylium us, 115, 174, 178
flavipes, 341, 343
Eurynorhynchus, 5, 337
Garrodia, 448, 449
Pygmæa, 5, 343 Garrulax albugularis, 177
Eurypyga, 147, 366, 377, 378, 380, 381, : Gastornis, 125, 468, 469, 533
Gecinus viridis, 185, 186, 187. See
helias, 377
also Picus viridis
Eurystomus, 205, 206, 207, 208
vittatus, 185
orientalis, 205
(Genyornis, 498
Excalfactoria chinensis, 291
Newtoni, 498
Geocichla citrina, 177
Geococcyx, 133, 134, 155, 161, 276,
FALCO, 75, 474, 475
277, 279, 281, 285, 395
æsalon, 473, 575
affinis, 279
biarmicus, 475, 477
Geopelia, 312, 314
brachypterus, 473
cuneata, 308
candicans, 475
humeralis, 308
Feldeggi, 475
Geophaps scripta, 309
lanarius, 475
Geopsittacus, 268, 269
peregrinus, 473, 475
occidentalis, 262
sacer, 475
Geotrygon, 312, 313
subbuteo, 473
violacea, 311
Francolinus, 291, 304
Geranoaetus, 474, 476
afer, 293
melanoleucus, 474
Clappertoni, 291
Geranopsis, 379 i
gularis, 293
Geronticus melanopis, 435
Fratercula, 360, 383
Glareola, 144, 341, 342, 350, 351, 380,
arctica, 41, 359, 362, 364,
383
365, 373
pratincola, 343
corniculata, 364
Goura, 14, 305, 311, 312, 314, 317
Fregata, 85, 93, 134, 150, 151, 161,
coronata, 308, 309
401, 402, 404, 405, 406, 409,-
Victoriæ, 308, 311
410, 411, 412, 413, 415, 416, 'Gracula intermedia, 172
417, 418, 450
javanensis, 175, 177
aquila, 402, 403, 407
Graculavus, 419
minor, 351
Grus, 75, 99, 366, 367, 369, 374, 33755,
Fregetta, 417, 448
377, 378, 379, 442
Firegilupus, 174
americana, 367, 368
Fulica, 17, 88, 322, 323, 329, 330
antiqua, 367, 368
ardesiaca, 322, 324
australasiana, 367, 368
atra, 321, 322, 331
canadensis, 367, 368
cristata, 331
carunculata, 366, 367, 368, 369
-
-
-
-
.
.
.
-
-.--
.. .
-.
-
.
-
-
--
INDEX
541
Grus cinerea, 368
Heteralocha, 5
leucogeranos, 366, 367, 368 Heterocnemis, 182
monachus, 57
Heteropelma, 180
virgo, 98, 366, 367
Hieracidea, 457
Guira, 272, 276, 277, 278, 280, 281
berigora, 475
piririgua, 279
Himantopus, 339, 341, 342
Gygis, 350, 351, 354, 356
andinus, 337
Gymnobucco, 196
brasiliensis, 343, 344
calvus, 195
nigricollis, 342, 344
Gymnoglaux pudipes, 246
| Hirundo, 174
Gymnorhina, 175, 176, 188
Houbara, 331, 332, 333
leuconota, 177
Macqueeni, 332, 334, 335
Gypaetus, 473, 474, 476
undulata, 332, 334
barbatus, 473, 474
Hybris, 245. See also Strix
Gypagus, 383, 481. See also : Hydrophasianus, 347
Gyparchus
chirurgus, 343
papa, 477, 481, 482, 484 Hydrornis ratator, 451
Gyparchus, 481, 482
Hylactes megapodius, 68
Gypogeranus, 13, 442. See also Ser- Hylomanes, 210, 211, 212
pentarius
gularis, 211
Gypohierax, 474
Hymenolæmus, 467, 468
Gyps, 476
Hypotenidia celebensis, 330
fulvus, 473
Hypoxanthus Rivolii, 185, 186
Gypsornis, 381
Hypselornis sivalensis, 498
-
-
---
-
-
--
--
--
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
----
-
HADROSTOMUS aglaiæ, 180
IANTHNAS, 312, 313
Hematopus, 150, 339, 340, 343
leucolæma, 308
ostralegus, 339, 343, 344 Ibidipodia, 444
Halcyon, 198, 200
Ibis, 423, 435
Lessoni, 199
ethiopica, 435, 439
smyrnensis, 198
. strictipennis, 435
vagans, 200
Ichthyornis, 21, 111, 112, 148, 160,
Halcyornis, 356
392, 469, 470, 471, 533
Halia, 174
agilis, 469
Haliaetus, 30, 55, 145, 398, 476
anceps, 469, 470
albicilla, 29, 30, 474, 477,478
dispar, 469, 470
vocifer, 477
tener, 469
Harpagornis, 484
validus, 469
Harpyhaliaetus coronatus, 474
victor, 469, 470
Heliodilus, 244, 351
Indicator, 61, 192, 196, 197, 229
Heliornis, 93, 325, 326, 327, 329, 397. !
major, 196
See also Podoa
Irrisor, 222"
surinamensis, 325. See also ! Ithaginis Geoffroyi, 293
Podoa surinamensis
lielotarsus, 476
ecaudatus, 473
JACAMEROPS, 213, 214
Hemipodius, 319
Jynx, 185, 186, 188
tachydromus, 320
torquilla, 185
varius, 321
Herpetotheres, 478
cachinnans, 476, 478 KETUPA, 249, 250
Hesperornis, 21, 121, 123, 134, 147, 149,
ceylonensis, 246
151, 160, 161, 385, 390,
jayanensis, 245, 246, 249
392, 393, 394, 395, 396,
406, 462, 469, 470, 471,
533
LAGOPUS, 304
crassipes, 392
Lanius, 174
gracilis, 392
| Laoptery?, 21, 154, 159, 523
Vegális, 392
priscus, 534
.
-
.
-
542
STRUCTURE AND CLASSIFICATION OF BIRDS
Larus, 112, 143, 350, 351, 354, 355, 446 | Macrodipteryx, 242 ,
argentatus, 352, 353, 354, 355, | Macropteryx, 226
360
mystacea, 226
fuscus, 353, 355
Macropygia, 311, 312, 313
glaucus, 353, 354, 355
leptogrammica, 308
Jamesoni, 354
Majaqueus, 445
marinus, 30, 352, 353, 354 Malacoptila fusca, 189
ridibundus, 353, 354
Manucodia, 59, 175
Lathamus, 253, 255, 259, 260, 267,
atra, 177
269, 270
Megacephalon, 291, 298, 299
discolor, 137, 262
maleo, 294, 296, 297,
Leptoptila, 312, 313
300
Leptoptilus, 93, 422, 425, 428, 429 | Megalæma, 101, 102, 141, 187, 191,
argala, 419, 425, 427, 428
192, 193, 195
crumeniferus, 425, 428
asiatica, 192, 193, 195, 196,
Leptosomus, 54, 205, 206, 207, 208
197
discolor, 206
Franklini, 192, 195
Lestris, 339, 350, 351, 353, 354, 357.
Hodgsoni, 192
See also Stercorarius
javensis, 192
antarcticus, 351, 352, 354, 355
virens, 192, 195, 196
crepidatus, 351, 354
Megalapterya', 524
pomatorhinus, 354
Megapodius, 291
Leuconerpes candidus, 185, 186, 187 Meiglyptes, 82, 194
Leucopternis, 476
Melanerpes erythrocephalon, 185
Leucosarcia, 312, 313
formicivorus, 185
picata, 311
Melanitta fusca, 463, 464
Licmetis, 263, 268, 269
Meleagris, 290, 291, 292, 298, 304
Limosa, 339, 340, 341, 343, 348
gallo-pavo, 290
ægocephala, 345
ocellata, 293
rufa, 343, 345
Melierax, 476, 478
Lipaugus cineraceus, 180
monogrammicus, 474, 478
Lithornis, 419
polyzonus, 474
vulturinus, 484
Melopsittacus, 12, 260, 268, 269
Lobiphasianus Bulweri, 293
Menura, 137, 146, 161, 172, 177, 182,
Lobivanellus, 337, 342
183, 298, 375
atronuchalis, 342
superba, 67, 173
Lomvia troile, 363, 364. See also Uria | Mergus, 455, 459, 462, 463, 465, 466,
troile
467, 468
Lophoaetus, 478
albicillus, 458, 459
occipitalis, 474, 477, 478
castor, 459
Lopholæmus, 310, 311, 312, 313
merganser, 458, 459, 460
antarcticus, 310
Merops, 208, 210, 447
Lophophorus impeyanus, 128, 293
ornatus, 209
Lophopsittacus mauritianus, 271 Mesites, 366, 370, 371, 377, 379, 380,
Loriculus, 260, 268, 269
383
galgulus, 262
Mesopteryx, 149, 524
chrysonotus, 262
Metopidius, 125, 347
Lorius, 20, 256, 259, 260, 263, 266,
africanus, 341
268, 269
peposaca, 459, 463, 468
domicella, 267
Metropelia, 312, 313
flavo-palliatus, 263, 266 Microglossa, 257, 263, 268
lory, 262
aterrima, 255, 256, 262
Lunda cirrhata, 359, 360, 361, 362, 364, Microhierax cærulescens, 473, 474,
365
· 475
Lyncornis, 243
Micropallas, 245
Micropus melanoleuca, 227, 229, 230
Milnea, 356
MACHÆRHAMPHUS Andersoni, 351
Milvago, 475
Machetes, 341, 343
chima-chima, 473
pugnax, 345
chimango, 474, 476
INDEX
543
Nycticorax caledonicus, 430
Gardeni, 97, 431
griseus, 431, 448
violaceus, 430
Nyctidromus, 234, 236, 237, 242
albicollis, 231, 235
Nyctiornis, 209
Nymphicus, 269
Nyroca, 463
leucophthalma, 459
Milvus, 476
ictinus, 474, 475, 477
Mitua, 291
tomentosa, 291, 293
tuberosa, 293
Memotus, 200, 210, 211, 212, 213
æquatorialis, 211
brasiliensis, 211
Lessoni, 211
Monasa, 188
panamensis, 188
nigrifrons, 189
Morphnus, 476
Motacilla, 174
Mulleripicus fulvus, 185
Mullerornis, 522
Musophaga, 17, 282, 283, 300
violacea, 283
Mycteria, 427
americana, 425, 428
Myiophoneus Horsfieldi, 177
u
NASITERNA, 268
Necropsittacus rodericanus, 271
Necrornis, 282
Neophron percnopterus, 473
Nesocichla eremita, 177
Nesolimnas, 330, 331
Dieffenbachii, 330
Nestor, 259, 260, 261, 263, 265, 267,
268, 270, 271, 457
meridionalis, 262
notabilis, 264
Nipponia Temminckii, 435
Nisaetus, 476
Nisus, 79
Nothocercus, 486
Nothocrax urumutum, 422
Nothura, 12, 99, 491
maculosa, 487, 488, 489, 490
491
major, 489
Notornis, 330
Mantelli, 330
Numenius, 5, 125, 150, 337, 338, 339,
OCYDROMUS, 322, 323, 324, 330, 331,
340, 341, 343
arquarus, 339, 344, 345
femoralis, 116
phæopus, 343, 378
Numida, 291, 293, 304
cristata, 293, 300
Edouardi, 293
meleagris, 293
ptilorhyncha, 293
vulturina, 293
Nyctes nivea, 245, 246
Nyctibius, 232, 241, 242
jamaicensis, 239
Nycticorax, 428
457
Earlei, 321, 322, 323, 324
lafresnayanus, 322
sylvestris, 322
Ocyphaps, 312, 313
Ocypterus, 174, 182
Odontophorus, 291
dentatus, 293
Odontopteryx, 384
tolicpicus, 21, 160, 418
(Edemia nigra, 464, 466, 468
dicnemus, 37, 146, 261, 333, 335,
338, 340, 343, 345, 348,
357, 383, 400, 448
bistriatus, 341, 343, 346
crepitans, 343, 344, 345
grallarius, 341, 343, 345.
See also Burrhinus
superciliaris, 343
Ena, 312, 317
Estrelata, 445
brevirostris, 447
Lessoni, 447
Opisthocomus, 17, 21, 54, 96, 97, 99,
108, 109, 116, 120, 123,
124, 128, 131, 144, 165,
284, 286, 287, 288, 289,
290, 317, 448, 532
cristatus, 108, 285, 286,
288
Oreopsittacus Arfaki, 253
Oriolus, 174
Ortalis, 292, 299
albiventris, 291, 294, 299
Orthonyx, 54
Ortyx cristata, 293
Gambelii, 293
virginianus, 293
Ossifraga, 445, 447, 449
Otidiphaps, 305
Otis, 80, 93, 98, 309, 318, 331, 332,
333, 334, 335, 379, 382
tarda, 332, 333, 334, 335
Otus vulgaris, 245. See also Asio otus
Panornis, 524
Palcccudyptes, 401
544
1
STRUCTURE TNT
OF BIRDS
AND CLASSIFICATION ·
I'alcelod115, 444
· Peruis, 133
Palæocicoitia, 444
apivorus, 17, 473
Palcogrus, 379
P’ezoplaps, 314, 315
Palæoperdix, 304
solitarius, 314
Palæornis, 260, 263, 268, 269 | Pha@thon, 150, 151, 226, 402, 03,
Alexandri, 262
404, 405, 406, 409, 410,
Palæolimnas chathamensis, 330
411, 412, 415, 417, 418
Palcortyx, 304
candidus, 351
Palceospheniscus, 401
flavirostris, 409
Palcotringa, 356
rubricauda, 351
Palamedea, 17, 76, 84, 88, 89, 91, 92, Phaëtbornis, 86, 226
94, 99, 102, 103, 107, Phalacrocorax, 14, 123, 134, 151, 384,
108, 110, 165, 304, 451,:
390, 404, 405, 406,
452, 454, 455, 500, 501, :
408, 409, 410, 411,
533
412, 413, 415, 410,
cornuta, 108
462
Pandion, 13, 17, 25, 103, 117, 245,
africanus, 404, 405
249, 253, 472, 478, 479, 484
bicristatus, 411
Panyptila melanoleuca, 226, 227
brasiliensis, 402, 403,
Paradiseа, 174
404, 405, 418
rubra, 173
carbo, 402, 403, 404,
Parra, 324, 340, 341, 347
405, 408, 410
albinucha, 347
graculus, 402
jacana, 341
lugubris, 405
sinensis, 342
perspicillatus, 411
Parus major, 30, 31
varius, 408
Pastor roseus, 177
Phaleris, 357, 363, 364
Pauxi galeata, 299
psittacula, 362, 363, 365
Patagona gigas, 226
Phaps, 305, 309, 311, 312, 313
Pavo, 16, 291, 292
chalcoptera, 305, 308
cristatus, 290, 293
elegans, 305, 308
muticus, 293
Pharomacrus mocinno, 99, 204
nigripennis, 293
Phasianus, 291, 304
spicifer, 293, 294
versicolor, 293
Pedionomus, 319, 320
Phebuetria, 2
torquatus, 319
Pheucticus, 175
Pelargopsis, 198
Philepitta, 174, 180, 181
Pelargornis, 419
Phlogænas, 312, 313
Pelecanoides, 2, 86, 122, 417, 445, 446,
cruentatus, 305, 307, 308,
447, 448
309
Pelecanus, 79, 150, 402, 403, 404, 405,
Stairi, 305, 308, 309
400, 400, 410, 410, 412, : Phenicophaäs, 275, 276, 27, 27, 280,
413, 415, 416, 417, 418
281
conspicillatus, 406
Phrenicopterus, 53, 73, 84, 93, 94, 101,
crispus, 406, 407
152, 336, 419, 440, 441
fuscus, 406, 407
Phonygama, 60
mitratus, 403, 406, 407 Phororhacos, 384, 385, 469
onocrotalus, 403, 406, 407
longissimus, 384
rufescens, 403, 406, 407, 409 Photodilus, 3, 244, 247, 248, 249, 250,
trachyrhynchus, 5
251, 252
Pelecyornis, 384
badius, 34, 244
Penelope cristata, 293
Phrenotrix, 173
cujubi, 294
Phytotoma, 182
jacucaca, 294
rara, 21
pileata, 294
Piaya, 274, 276, 277, 278, 280
Perdicula, 298
cayana, 241, 274, 275, 277, 279
Perdix, 146, 290
Picoides, 2
cinerea, 293
tridactylus, 185
Peristera, 312, 313
Picolaptes affinis, 185
Geoffroij, 305
l'icus, 98
· INDEX
515
Picus major, 185
Pæcilonetta bahamensis, 459
minor, 185, 186
Pæocephalus; 256, 259, 260, 261, 268,
viridis, 184, 185. See also 270
Gecinus viridis
Pogonorhynchus bidentatus, 195
Pionopsitta, 269
Polyboroides, 472, 474, 479
pileata, 262
typicus, 474
Pionus, 254, 256, 257, 269, 270
Polyborus, 474
Maximiliani, 262
brasiliensis, 474, 476, 477
senilis, 262
Polyplectron bicalcaratum, 293
Pipile cumanensis, 294
chinquis, 293
jacutinga, 294
Polyteles, 256, 257, 268
Pitta, 181
melanurus, 258
Platalea, 24, 30, 409, 422, 423, 429, Porphyrio, 55, 87, 324
435, 439, 442
madagascariensis, 322"
, ajaja, 435, 436, 438, 439 ( = P.
martinicus, 323
· rosea, q.v.)
Porzana carolina, 321, 322
alba, 438
notata, 322
leucorodia, 55, 57, 435, 437, Prion, 446
439
Prioniturus, 268, 269
rosea, 227, 434 (= Platalea Prionorhynchus, 210
ajaja, q.v.)
Procellaria, 445
Platycercus, 255, 256, 257, 261, 263, 269,
gigantea, 449
270
Propelargus, 444
Barnardi, 258, 261, 262 Psarisomus, 178
pallidiceps, 261, 262
Psephotus, 255, 260, 269, 270
Pennanti, 264
Psittacula, 86, 260, 269, 270
Plectropterus, 452, 465, 466
passerina, 254, 351
gambensis, 458, 459, Psittacus, 89, 254, 256, 257, 259, 260,
465, 466, 468
263, 266, 269, 270
niger, 459, 465
erithacus, 262, 263
Ruppelli, 465
Psittinus, 268, 269
Plegadis falcinellus, 435
malaccensis, 262
Plotus, 19, 134, 384, 402, 403, 404, Psophia, 16, 123, 137, 143, 146, 161,
405, 406, 408, 409, 410, 411,
165, 298, 357, 366, 371,
412, 413, 415, 416, 418
374, 375, 376, 377, 378,
anhinga, 22, 402, 403, 412,
379, 382
413, 414, 415
leucoptera, 375, 376
Levaillanti, 403, 413, 415 | Pterocles, 3, 34, 80, 85, 148, 288, 307,
melanogaster, 402, 403, 413,
308, 309, 313, 315, 316
415
317, 318, 351, 386
Nove Hollandiæ, 413
alchata, 316
Pluvianus, 350
arenarius, 316, 317
Pnoepyga, 173
Pteroglossus, 190
Podargus, 73, 74, 79, 98, 101, 232, 234,
Wiedi, 192
235, 237, 239, 240, 242, Pteroptochus, 299
243, 244
Ptilonorhynchus holosericeus, 177
Cuvieri, 231, 235, 236
violaceus, 99, 175
Podasocys montanus, 338
Ptilopachys, 298
Podica, 325, 326, 327, 329, 404, 446
ventralis, 300
senegalensis, 93, 128, 325, 327, Ptilopus, 305, 306, 307, 309, 312, 314
328
assimilis, 305
· Podicipes, 98, 326, 327, 386, 389,
jambu, 306, 308
394
melanocephalus, 308
cornutus, 388, 389
coronulatus, 305 307, 303
cristatus, 387, 389
puella, 305
minor, 387, 388
superbus, 305, 307
Podilymbus, 386
Pulsatrix, 246
Podoa, 391
torquata, 245, 246
surinamensis, 325. See also ! Pygosceles, 396, 398, 399, 400
Heliornis surinamensis
papua, 397
Ν Ν
546
OF BIRDS
10
STRUCTURE AND CLASSIFICATION Pyrrhocentor, 275, 276, 277, 278, 279, 1 Rollulus coronatus, 293
281
Rupicola, 54, 179
celebensis, 279
Pyrrhula, 268, 270
SARCIDIORNIS, 452, 462, 465
Pyrrhulopsis, 255, 266, 257, 260, 263,
carunculata, 459, 468
269, 270
melanonota, 459, 461
personata, 264
Sarcorhamphus, 50, 101, 481, 482
splendens, 262
Sauromarptis, 198
Gaudichaudi, 198
QUENQUEDULA circia, 459
Sauropates, 198
crecca, 467
albicilla, 198, 199
Quiscalus versicolor, 176
sanctus, 198
Saurothera, 272, 274, 276, 277, 278,
RALLOS, 143, 322, 331
280
aquaticus, 321, 322
dominicensis, 279
maculatus, 323
Scaniornis, 414
Recurvirostra, 5, 337, 338, 341, 343, Schizorhis, 282, 283, 294
348, 357
africanus, 283
avocetta, 337, 339, 343 Scolopax, 337, 341, 342, 343
Remiornis, 419
rusticola, 343, 344, 345
Rhamphastos, 17, 25, 81, 190, 194 Scops asio, 245
ariel, 192
Lempiji, 245, 246
carinatus, 99, 190
leucotis, 245, 251
Cuvieri, 83
Scopus, 99, 343, 419, 420, 421, 422, 432,
dicolorus, 190, 191
434, 440
tocard, 190
umbretta, 118, 420, 434
Rhea, 2, 18, 34, 81, 101, 108, 128, 132, Scythrops, 241, 275, 278, 279, 280
140, 162, 311, 490, 491, 495, Selenidera, 190
497, 498, 500, 502, 503, 505, Seleucides, 174
506, 507, 509, 511, 512, 513,
nigra, 58, 177
514, 525, 526, 527, 528
Serilopha, 178
americana, 34, 498, 506, 507, | Serpentarius, 57, 93, 145, 336, 382,
508, 511
472, 474, 479, 480,
Darwini, 34, 505, 507, 511
481, 484. See also
macrorhyncha, 506, 511
Gypogeranus
Rhinochetus, 17, 146, 147, 149, 232,
reptilivorus, 477
335, 357, 366, 370,
robustus, 484
371, 372, 377, 378, Somateria, 463
379, 380, 381, 383,
mollissima, 464
441, 480
Spatula clypeata, 459
jubatus, 369, 370
Speotyto, 247, 248
Rhinococcyx, 272, 280
cunicularia, 246, 247
Rhinogryphus, 481
Sphagolobus atratus, 219, 221. See
californianus, 473
Celso Buceros atratus
Rhinopomastus, 222,
Sphepiscus, 360, 396
Rhodonessa caryophyllacea, 459, 461
demersus, 41, 397, 398, 400
Rhyncha, 16, 337, 342
Humboldti, 400
australis, 60, 345
magellanicus, 398
capensis, 60, 345
mendiculus, 397
Rhynchops, 5, 78, 350, 351, 352, 353, Sphyrapicus nuchalis, 184
355, 470
varius, 185
Rhynchotus, 83, 489, 491
Spiloglaux Nova Zelandiæ, 244
perdicarius, 486
Spilornis, 476
rufescens, 31, 486, 487
bacha, 473
489, 491, 492
cheela, 473
Rhytidiceros plicatus, 99, 289. See Spizaetus, 54, 476
also Buceros plicatus
caligatus, 477
Rimator malacoptilus, 177
· coronatus, 57, 477
Rissa tridactyla, 351, 354
Squatarola helvetica, 344
Rollulus, 291
Starnænas, 312, 314
INDEX
547
434
Steatornis, 69, 70, 112, 147, 161, 232, 1 Tadorna tadornoides, 459
233, 234, 235, 236, 237,
vulpanser, 466
239, 240, 241, 242, 243, Taleyalla, 291, 298, 299
276
Lathami, 294, 300, 304
Caripensis, 233, 234, 235, Tanagra festiva, 177
240
sayaca, 177
Stercorarius, 351. See also Lestris Tantalus, 71, 422, 423, 425, 428, 429,
s'tercornis, 385
442, 491
Sterna, 20, 126, 338, 350, 352, 353, 354,
ibis, 22, 425, 426, 428
470
leucocephalus, 427
cantiaca, 354
loculator, 66, 68, 425, 423,
hirundo, 20, 359
Sternula, 356
Milne-Edwardsi, 444
Strepera, 175
Tanygnathus, 256, 257, 260, 268, 269
graculina, 177
Muelleri, 262
Strepsilas, 343
Tanysiptera, 197, 199, 200
interpres, 343, 345
Taoperdix, 304
Strictonetta nuevosa, 463
Telinatornis, 471
Stringops, 128, 253, 257, 258, 259, 260, Teracus, 484
261, 262, 263, 265, 266, Tetragonops, 192
268, 269, 270, 271, 457, | Tetrao, 290, 291, 298, 304
520
cupido, 293, 303
habroptilus, 255, 256, 264
pbasianellus, 293
Strix, 244, 245, 247, 248, 249, 250, 252.
tetrix, 293, 296
See also Hybris
urogallus, 60, 293, 298, 301
flammea, 245, 247
321
Novæ Hollandiæ, 245
Tetrapteryx, 368, 369, 375
pratincola, 245
Tetrax, 2, 331, 332, 333
Tengmalmi, 245
campestris, 332
Struthidea cinerea, 43, 177
Thalassiarche, 86, 353
Struthio, 12, 28, 30, 64, 82, 85, 88, 89, 1. Thalassæca glacialoides, 449
148, 462, 493, 495, 498, Thaumalea Amherstiæ, 293
500, 501, 502, 503, 506,
picta, 292
507, 510, 512, 525, 526, Thinocorus, 21, 144, 318, 319, 338, 349
527, 528
rumicivorus, 341, 343, 350
camelus, 28, 495, 505, 506 Thrasaetus, 476
molybdophanes, 495
harpyia, 473
Sturnella, 174
Tiga, 2
Sula, 403, 404, 405, 408, 411, 412, 413, javaneosis, 185
415, 416, 418
Shorei, 184, 185
bassana, 403, 404
Tigrisoma brasiliense, 430, 431
fusca, 404
leucolophum, 378
Surnia funerea, 246
Tinamus, 134, 394, 395
Syma, 199, 200
robustus, 490
Synallaxis, 182
solitarius, 486, 487, 489, 491
Synthliborhamphus, 359
Tinnunculus, 474, 477
antiquus, 359, 360,
alaudarius, 101, 473, 475
361, 363, 364, Toccus, 116, 216, 218, 222, 487
365
Todirhamphus, 198
Syrnium, 42
Todus, 16, 212, 213, 241
aluco, 245, 246
Totanus, 341, 343
nebulosum, 245, 246
calidris, 343
Syrrhaptes, 3, 33, 315, 317
canutus, 345. See also Tringa
paradoxus, 34
canuta
Trachyphonus, 194
Treron, 312, 314
TACHYBAPTES, 386, 388
Tribonyx, 323
fluviatilis, 389
Mortieri, 322
Tachyeres, 460, 466
Trichoglossus, 255, 256, 257, 266, 268,
cinereus, 456, 466, 468
269
548
AND CLASSIFICATION OF BIRDS
T1
STRUCTURE Tringa, 343
Uria troile, 359, 360, 365. See also
alpina, 344
Lomvia troile
arenarius, 344
Urogalba, 213, 214
-canutus, 341, 342, 343. See also
paradisea, 214
Totanus canutus
Urubitinga, 476
cinclus, 345
Triponax Feddeni, 120, 188
Trochalopteron, 175
VANELLUS, 341, 343, 346, 348
Trochilus Alexandri, 229, 230
cayennensis, 66, 67, 343,
colibris, 227, 228
344
Trogon gallicus, 202
c istatus, 341, 344
mexicanus, 204
Vultur, 476
puella, 203, 204
auricularis, 473, 474 475
Reinwardti, 204
calvus, 478
Turacæna, 312
fulvus, 474
Turdus, 174
monachus, 473
Turnix, 319, 320
Kleinschmidti, 320
lepurana, 320
XANTIIOLÆMA, 192, 193
rostrata, 321
Sykesi, 320
rosea, 193, 195
Turtur, 312, 313
Xenicus, 173, 181
Tympanistria, 312, 313
Xenorhynchus, 65, 95, 424, 429, 432,
bicolor, 308
491
australis, 425, 428
senegalensis, 424, 425,
UPUPA, 81, 222
428
Uranornis rubra, 177
Uria, 360, 362, 363, 394
columba, 359, 301, 363, 364, | ZENAIDA, 312, 313
365
Zenaidura, 312, 313
PRIXTID BY
SPOTTISWOODE AND CO., NEW-STRČET SQUARE
LONDOS

UNIVERSITY OF MICHIGAN
US
LI
JU
IM
III
3 9015 00689 1058
THE UNIVERSITY OF MICHIGAN
et mere
DATE DUE
marsro
ins
room
MAY, &1999999


1
.
....
.
鲁鲁华
​重量
​畢書畫書
​..
,
,
,
工事
​“..
11
·
1、
譯
​|
|
|
:雪
​看看​,
,
事
​'',
其一
​賽
​.
,
上陣​。
。
..
「...
^ ^"
.
.
地
​1
.
:“
...
,
...
.
“
中
​意事
​'.
.
,
|-
背景
​.
;
青重
​臺s
::
:
*:
"-
1"
*
,
=
,
1
.
..
|
本本​!
,
上
​.
“
一半​,
..
重重疊疊​,
我
​4
?
.
.
「
|
|
1
“青
​。
.
.
A. I'
會畫畫​。
t
..
.
要
​,
|
「
書
​"
:
重​”。
重量​。
;
-
| .
;
:,
量
​:
其
​.
*
「..
.,
*
.
件事
​:
,
“育​”
:
::
:
:
。
作​。
|-
「
「老實
​十
​,
萬華-
​i
TF事​,出事
​:
4
,
,
r:
車
​#
.
,
1
,
.
:.
1.
..
料
​:
#
.
*
4
,
”
,
“
,
,
,
.
..
.
.
:
一
​..
.
.
事事事​,
,
:
::
11
鲁
​:
:
,
鲁
​事​,
上
​子
​,
**
,
.*"-
产​,
“
,
然
​":"
学
​可
​一
​”
.
|
一​。
」
..
中
​,
..
.
.
4
*
-
.
?
"
'
:
.
:
:
事业
​i
會
​了​,
,
:,
.
-
4
,
.
.
,
看看​。
事​,
.
美​。
.
:
:
*
.
.
步​。
.
并
​1.
-
-
传
​“是​。
”
·
書
​,
:
|
,
,
,
,
T
"
,
「.
stus,
不然我
​毒
​等
​,
.
重
​,,
,
",
".
.
A
「
.
“
:
,
,
<t
車
​:
'
I
;
"
重量​,
车事看
​,
,
,
,
:
。
事事​。
:
事
​,
實
​其
​作​,
.
..
市
​本​。
,
1
|
法治
​“音
​Lif",
"
L
",
")
"
2.