UNIVERSITY OF CALIFORNIA SAN FRANCISCO LIBRARY HENRY I. FL^ISSia Digitized by the Internet Archive in 2007 with funding from IVIicrosoft Corporation http://www.archive.org/details/anatomymanualforOObrocrich HBNrv i.fleissig The Students' Quiz Series. A series covering the essential subjects of a thorough medical education, arranged in form of quesUon and answer. By qualified teachers and examiners in New York. Illustrations ivherever desirable. Priced at uniform low rate of $1.00, except double numbers on Anatomy and Surgery, which are priced at $1.75 each. ANATOMY {Double Number)— By Fred J. Brockway, M.D., Ass't Demonstrator of Anatomy, College of Physicians and Surgeons, New York, and A. O'Malley, M.D., Instructor in Surgery, New York Polyclinic. $1.75. PHYSIOLOGY— By F. A. Manning, M.D., Attending Surgeon, Manhattan Hospital, N.Y. $1.00. CHEMISTRY AND PHYSICS— By Joseph Struthers, Ph. B., Columbia College School of Mines, N. Y., and D. W. Ward, Ph. B., Columbia College School of Mines, N. Y., and Chas. H. Willmarth, M.S., $1. HISTOLOGY, PATHOLOGY AND BAC- TERIOLOGY— By Bennett S. Beach, M.D., Lecturer on Histology, Pathology and Bacteriology, New York Polyclinic. $1.00. MATERIA MEDICA AND THERAPEU- TICS— By L. F. Warner, M. D., Attend- ing Physician, St. Bartholomew's Dispen- sary, N. Y. $100. PRACTICE OF M E Dl CI NE-By Edwin T. DouBLEDAY. M. D., Member N. Y. Patho- logical Sociei/, f nd J. D. Nagel, M. D., Member N. Y. County Medical Associa- tion. $100. SURGERY {Double Number)— By Bern B. Gallaudet, M. D., Visiting Surgeon Bellcvue Hospital, N. Y., and Charles Dixon Jones, M.D , Surgeon to York- ville Dispensary and Hospital, N. Y. $1.73. GENITO-URINARY AND VENEREAL DISEASES— By Chas. H. Chetwood, M. D., Visiting Surgeon, Demilt Dispen- sary, Department of Surgery and Genito- urinary Diseas.es, New York. $1.00. DISEASES OF THE SKIN— By Charles C. Kansom, M. D., Assistant Dermatolo- gist, Vanderbilt Clinic, N. Y. $1.00. DISEASES OF THE EYE, EAR, THROAT AND NOSE— By Frank E. Miller, M. D., Throat Surgeon, Vanderbilt Clinic, N. Y., James P. MacEvoy, M. D., Throat Surgeon, Bellevue Hospital, Out- Patient Department, New York, and J. E. Weeks, M.D., Lecturer on Oph- thalmology and Otology, Bellevue Hos- pital Medical College, New York. $1.00 OBSTETRICS — By Charles W. Hayt, M. D., House Physician, Nursery and Child's Hospital, New York. $1.00. GYNECOLOGY— By G. W. Bratenahl, M. D,, Assistant in Gynecology, Vander- bilt Clinic, New York, and Sinclair TousEY, M. D., Assistant Surgeon, Out- patient Department, Eoosevelt Hospital, New York. $100. DISEASES OF CHILDREN — By C. A Rhodes, M.D., Instructor in Diseases of Children, N. Y. Post-Graduate Medical College. $100. LEA BROTHERS & CO., PUBLISHERS, PHILADELPHIA. Th^ Students' Quiz Si^ips ^^, AN A TO mT *%. A MANUAL FOR STUDENTS AND PRACTITIONERS. BY FRED J. [brock WAY, M. D., Assistaiit Demonstrator of Anatomy, College of Physicians and Surgeons, Neiv York, AND A. O'MALLEY, M. D., Instructor in Surgery, New Yoi'k Polyclinic. SECOND EDITION, ^WITH FULL-PAGE PLATES. SERIES EDITED BY BERN B. GALLAUDET, M.D., Demonstrator of Anatomy, College of Physicians and Surgeons, New York ; Visiting Surgeon Bellevue Hospital, New York. QH2.2, PHILADELPHIA ; LEA BROTHERS & CO. Entered according to Act of Congress, in the year 1893, by LEA BROTHERS & CO., In the Ofl&ce of the Librarian of Congress, at Washington. All rights reserved. Westcott & Thomson, William J. Dornan, Stereoiypers and Electrotypers, Philada. Printer, Philada. HENUY I. FLEISSia PREFACE. The opportunity aiForded by the preparation of this book for the presentation of a brief Modern Anatomy has been deemed too valuable to sacrifice by duplicating existing " Anatomical Com- pends." The science is steadily advancing in the discovery of new facts. Twenty years ago the German anatomists recorded dis- coveries which are only now coming to the notice of the American student. A hand-book can at most contain only the essentials of the science, and in the present instance the effort has been to select such knowledge as will be most useful to the student and the practitioner. In the hope of presenting some new descriptions not acces- sible to all students, I have compiled the sections on Osteology, Arthrology, and Myology from Henle and from Quain, while Gray's Anatomy and notes on the lectures of Prof. George S. Huntington of the College of Physicians and Surgeons, New York, have also been largely consulted. The order and classification of Henle have been followed throughout: joints are mostly from his work, and where his descriptions of them differ greatly from those of Eng- lish text-books, they have been described separately in fine print. Many muscular anomalies have been mentioned in fine print. New names for muscles as agreed upon by the German Ana- tomical Society have been marked ^' p. n." (proposed name). Illustrations from Gray, Quain, Henle, and Schwalbe have been reproduced to illustrate special points. English and metric meas- urements are both given, the English being approximately correct. IV PREFACE. Space has been gained by conciseness and by the omission of many monosyllabic words. It is to be noted that the questions are, in a sense, headings introducing generally a large amount of informa- tion in the answers. The Glossary has been written in the hope of promoting a cor- rect pronunciation of anatomical terms. I have to acknowledge the assistance of Dr. Andrew O'Malley and the Editor of the Series, who have written the sections on Angeiology, Neurology, and Splanchnology. In the latter section the relations of the viscera are with slight modifications those given by Professor George S. Huntington, and the works of Quain and Gray serve as the basis for the general descriptions of the viscera, as well as for the sections on Angeiology and Neur- ology. This volume is not intended to replace text-books, but will be found serviceable in facilitating the remembrance of knowledge gained from more extended works and at the dissecting-table. FRED J. BROCKWAY. 105 W. 74th St., \ New York, j lajBJNK.^^ I' Fl^EISSia CONTENTS. PAGE Definition and Subdivisions of Anatomy 17 Embryology 17 Descriptive Anatomy 19 OSTEOLOGY. Bones of the Trunk : The Vertebral Column ; False Vertebrae ; Ossification of the Vertebrae ; The Thorax ; The Hyoid Bone . . 23 Bones of the Head : Bones of the Cranium ; Bones of the Face ; The Skull as a Whole ; The Wormian Bones ; External Surface of the Skull ; Ossification of the Bones of the Head ...... 35 Bones of the Upper Extremity : The Shoulder ; The Arm ; The Forearm; The Hand 64 Bones of the Lower Extremity : The Pelvis ; The Thigh ; The Leg; The Foot 76 AKTHKOLOGY. Henle's Classification of Joints 93 Articulations of the Trunk and Head : Henle's Vertebral and Costal Ligaments 95 Articulations of the Upper Extremity: The Shoulder-girdle and Joint ; The Elbow and Forearm ; The Wrist and Carpus ; Accessory Ligaments of the Wrist 104 Articulations of the Lower Extremity: The Pelvic Girdle; Ligaments between tlie Bones of the Trunk and Hip-bone ; The 5 6 CONTENTS. PAGE Hip-joint; The Knee-joint; Ligaments between the Bones of the Leg; The Ankle-joint; Joints of the Foot; Heule's Classi- fication of the Ankle- and Foot-joints 120 MYOLOGY. Muscles in General 138 Muscles of the Trunk : Muscles and Fasciae of the Back ; Muscles and Fasciae of the Abdomen; Lining Fasciae of the Abdomen; Muscles and Fasciae of the Chest; Muscles and Fasciae of the Neck ; Muscles of the Head 139 Muscles and Fascia of the Extremities: 173 The Upper Extremity : The Shoulder ; The Upper Arm ; The Fore- arm ; The Hand 173 The Lower Extremity: The Hip and Thigh ; The Leg; The Foot . . 186 Muscular Homologies 202 ANGEIOLOGY. The Heart: Structure of the Heart 204 Arteries: The Pulmonary Artery 208 Systemic Arteries: Arch of the Aorta and its Branches; Arteries of the Head, Neck, and Upper Extremity ; The Thoracic Aorta and its Branches; Tlie Abdominal Aorta and its Branches; The Iliac Arteries and their Branches; Arteries of the Lower Ex- tremity and their Branches 208 Veins : The Pulmonary Veins 233 Systemic Veins: Superior Vena Cava and Innominate Veins; Veins of the Head and Neck ; Veins of the Upper Extremity ; Veins of the Trunk ; Veins of Lower Extremity ; Veins of the Pelvis ; The Portal System 233 The Absorbent System 245 NEUROLOGY. The Spinal Cord 249 The Brain or Encephalon 252 CONTENTS. / PAGE Cranial Nerves 266 The Spinal Nerves 277 The Sympathetic Nervous System 292 Organs of Special Sense: The Eye; The Ear; The Nose; The Tongue 297 SPLANCHNOLOGY. Organs of Respiration : The Larynx ; The Trachea ; The Thyroid and Thymus Glands ; Pleurae and Mediastinum ; The Lungs . . 310 The Organs of Digestion : The Mouth ; The Teeth ; The Palate ; The Tonsils; The Salivary Glands; The Pharynx; The CEsopha- gus; The Stomach; The Small Intestine; The Large Intestine; The Liver ; The Gall-bladder ; The Pancreas 318 The Spleen and Suprarenal Capsules : The Spleen ; The Supra- renal Capsules 335 The Urinary Organs and Peritoneum : The Kidneys ; The Ureters; The Bladder; The Peritoneum 336 Organs of Reproduction (Male) : The Prostate Gland ; The Penis ; The Male Urethra ; The Testes 342 Organs of Reproduction (Female) 348 External: The Vulva; The Vagina 348 Internal : The Uterus ; The Fallopian Tubes ; The Ovaries ; The Parovarium 349 The Mammary Glands . 352 ANATOMY. DEFINITION AND SUBDIVISIONS OF ANATOMY. What are the object and subdivisions of anatomy ? Its object is to find out the structure of organized bodies. This sci- ence includes Human, Comparative, and Vegetable Anatomy. The animal possesses two tubes, the animal and vegetative : the former contains the spinal cord and brain, distinguishing in part the animal from the plant ; the vegetative tube is common to both, and encloses the organs of nutrition and reproduction. Human Anatomy is subdivided into Histology, or General Anatomy, and Descriptive, or Special Anatomy. The following pages treat of Descriptive xAnatomy. EMBRYOLOGY. Briefly describe the process of development. The human ovum is a small cell, j^th inch in diameter ; its wall is the vitelline membrane^ its body the yolk^ its nucleus the germinal vesicle^ and its nucleplus the germinal spot. If all the food-yolk undergoes changes, as in mammals, the ovum is holohlastic ; if only part, as in fishes, it is merohlastic. When the ovum matures the germinal vesicle divides and extrudes two polar globules; inside the yolk is formed a female pronucleus. These changes occur whether the ovum is fecundated or not. Should another cell, the spermatozoon^ enter the yolk, its tail disappears and its head becomes the male pronucleus. The union of the two pronuclei forms the first segmentation sp^hei^e. Halves are formed of this sphere, each one again splits, and so on : when about ninety -six cells are formed, an upper group of sixty-four will completely enclose a lower group of thirty-two. The outer group lines the vitelline membrane, and from it comes the primitive ectoderm, the epihlast or serous layer. From the enclosed group comes the primitive entoderm, the hypoblast or mucous layer ; be- tween them is later developed the primitive mesoderm., the mesoblast or vascular laj^er. On the outer layer there appears a shaded patch, the area germinativa, and in this come in order (1) the primitive streak, (2) the medullary canal, (3) the chorda dorsalis or notochord, and (4) the 2— A. 17 18 ANATOMY. mesohlastic somites : the first is transient ; the third, round which the vertebral column forms, is more persistent; the second and fourth are permanent. The primitive streak soon acquires a primitive groove. The medullary or neural canal is confined to the epiblast, and formed by two lateral ridges meeting dorsally. The chorda dorsalis is a thicken- ing of the hypoblast, and its remains are the centres of the interverte- bral disks. The lateral mesoblast cleaves into two plates : one clings to the epiblast, forming the somatojyleure ; the other to the hypoblast, form- ing the splanchnopleure. The former forms part of the wall of the body, the latter part of the wall of the alimentary tract, and between the two is the coeJom, or pleuro-peritoneal cavity. In the paraxial mesoblast, in the region which afterward becomes the neck, is developed a linear series of quadrangular masses, the meso- hlastic somites. At the anterior end of the neural groove are formed three primary cerebral vesicles ; later the anterior and posterior divide each into two, making five in all. The steps to be noted are — (1) formation of polar globules and the male and female pronuclei ; (2) segmentation of yolk ; (3) arrangement of cells inside the vitelline membrane into two groups ; (4) separation of cells into epiblast, mesoblast (two layers), and hyjjoblast; (5) formation of area germinativa; (6) primitive trace; (7) primitive groove caused by heaping up of "dorsal plates;" (8) neural canal^ formed by the meeting of dorsal plates; (9) under this canal formation of notochord from hypoblast; (10) a line of square segments, the mesohlastic plates; (11) somatopleure and splanchnopleure and body-cavity; (12) three primary cerebral vesicles ; (13) curving of the embryo longitudinally and laterally, comparable to a canoe, the body-cavity corresponding to the well of the canoe ; (14) the yolk-sac outside the 'body-cavity is the um- bilical vesicle, providing nutrition until the placenta is formed. What parts are derived from each blastodermic layer ? From epiblast^ the whole nervous system, brain, spinal cord, peripheral and sympathetic nerves; epithelial structures of the organs of special sense ; epidermis and appendages, as hair and nails ; epithelium of glands which open upon the skin surface, as mammary, sweat, and sebaceous glands ; muscular fibres of sweat-glands ; epithelium of mouth, except that covering tongue, and of glands opening into it ; enamel of teeth ; epithelium of nasal passages and of glands and cavities opening into them. • From mesoblast^ genito-urinary organs, except epithelium of bladder and urethra; all voluntary and involuntary muscles, except muscular fibres of sweat-glands ; vascular and lymphatic systems ; serous mem- branes and spleen ; skeleton and all connective-tissue structures of body. From hypoblast^ epithelium of alimentary canal from back of mouth to anus, and of glands which open into this part of the tube ; epithelium of Eustachian tube and tympanum ; epithelium of bronchial tubes and OSTEOLOGY. 19 air-sacs of lungs ; epithelium of the vesicles of the thyroid ; epithelial nests of the thymus ; epithelium of urinary bladder and urethra. DESCRIPTIVE ANATOMY. What are the systems of descriptive anatomy? 1 . Osteology, the bones ; 2. Arthrology, the articulations ; 3. IMyol- ogy, the voluntary muscles, fasciae, and aponeuroses ; 4. Angeiology, the heart, blood-vessels, and lymphatics ; 5. Neurology, spinal cord, brain, nerves, and organs of the senses ; 6. Splanchnology, the organs of res- piration, digestion, reproduction, and urination. An organ is capable of isolation : organs make up a S3^stem, and sys- tems an apparatus. What are some of the descriptive terms ? The body is always supposed to stand erect, with hands at the sides and palms to the front. Superior and inferior correspond to cephalic and caudal^ anterior and posterior to ventral and dorsal. As the body is bilaterally s^^mmetrical, it may be divided into similar halves by a median plane passing from before backward. The line along which this plane meets the surface of the body is the median line. The words in- ternal and external refer to points nearer to or farther from the median plane. Henle uses median for internal, and lateral for external ; the ibrmer looks toward the median line, the latter from it. Sagittal denotes an antero-posterior direction in or parallel to the median plane ; coronal or frontal denotes a transverse direction at right angles to the sagittal. Other terms applied to surfaces or borders, like vertebral., sternal^ radial., idnar^ flexor, extensor, proximal (nearest the trunk or centre), distal (away from the trunk), are often convenient. A surface is said to " look " in a certain direction when a perpendic- ular to the surface points in that direction. OSTEOLOGY. What is the skeleton ? The skeleton is the sohd framework of the body, composed of bones completed by cartilage. In the lower animals there may be an endo- skeleton, the deeper framework corresponding to the human skeleton, and an exoskeleton, comprising the integument and hardened structures connected with it. All vertebrate animals possesses an endoskeleton ; some have an exoskeleton. Most invertebrate animals possess an exo- skeleton only. What are the uses of bones ? (1) They serve as levers upon which attached muscles act ; (2) sup- port ; (3) protection of delicate organs ; (4) contribute to the formation of joints ; (5) by elasticity of curvature tend to diminish shocks. 20 OSTEOLOGY. How are bones formed ? They are formed by ossification in three ways: (1) in cartilage, not from it; (2) in membrane; (3) subperiosteally. The bones of the vertex of the skull — i. e. the parietals, the frontal, the tabular part of the occipital, the squamous and tympanic parts of the temporal, the inner plate of the pterygoid process, the bones of the face except the inferior turbinate and part of the lower jaw— are formed in membrane. The base of the skull and the other bones of the body are formed in cartilage. A deposit of bone begins at one spot, the primary centre ; the shaft or diaphysis is formed from this. Most bones have other centres of ossification, secondary^ or tertiai^^ and parts de- rived from them are the epiphyses [growing upon). The growth of bone in length depends largely upon the cartilage between the epiphysis and diaphysis ; this cartilage acts as a bufier in concussions. The growth in circumference is by subperiosteal ossification. Some bones ossify early, according to their function — e. g. the lower iaw and ribs, because suction and respiration come into play at birth. The first primary centre to appear is in the clavicle, at the fifth week of foetal life ; the last secondary centre to appear is in the sternal end of the clavicle, at the eighteenth year. At birth nearly all primary centres have appeared (the pisiform not till the twelfth year), and only one secondary centre — viz. that for the lower extremity of the femur, pos- sibly one for the upper extremity of the tibia. What are the rules for the direction of medullary arteries ? 1. The medullary arteries r\mfrom the knee and toward the elbow. 2. The secondary centre /ro?7i which the artery runs is t\iQ first to appear. 3. The epiphysis ^/'.sf to appear is la^'it to unite (except in case of fibula, where its lower epiphysis appears first and unites first). If there is but one secondary centre in a bone, the artery runs from it. Rule 1 may be remembered by flexing the knees and elbows, and noting that the medullary arteries run down as though impelled by gravity. The obliquity of the vascular canals is really due to the inequality of growth of the two ends : the one growing more rapidly carries the artery with it. Briefly describe the structure of bone. This description includes that of the periosteum, marrow, and bone proper. The periosteum, or bone-skin, consists of two layers, an outer fibrous and an mner vascular one, beneath which are granular cells called osteo- blasts. The periosteum serves as a nidus for vessels, and is related to the growth and renewal of bone. It is looser on young bone than on old, and looser on the shaft than on the extremities. The dura mater of the brain is allied to periosteum. The marrow fills the medullary canal, cancellous spaces, and large OSTEOLOGY. 21 Haversian canals. The medullary canal is lined with endosteum. Marrow may be yellow or red: the former is in adult long bones and contains 96 per cent. fat. In the short and flat bones, in the cancellated ends of long bones, in the bodies of the vertebrae, in the cranial diploe, in the sternum and ribs, and in all bones of the foetus and infant, the marrow is red and fluid, containing 72 per cent, water and a trace of fat. Marrow may possess five kinds of cells: (I) fat- cells; (2) marrow-cells proper, resembling white blood-cells, and possess- ing amoeboid movement; (3) small nucleated reddish cells; (4) cells containing one or two red blood-corpuscles ; (5) giant-cells (osteoclasts or myeloplaxes), which are concerned with bone-absorption. Marrow may help form and renovate blood, form bone, and has nutritive properties. Bone proper may be compact or cancellous ; the separate cancelli have the same structure as the compact bone. Long bones have an outer shell of compact substance, spongy tissue at the ends, with a dense layer beneath the articular cartilage, and a medullary canal. Flat bones have two compact plates enclosing a spongy layer, the diploe. Solid bone is made up of Haversian systems (Havers, an English phy- sician). A central hole is the Haversian canal, ^^Jx) inch in diameter, and five to fifteen concentric rings around it are the lamellce. Between the lamellae are dark specks, the lacunce^ which are connected with each other and the central canal by fine lines, the canaliadi Lamellae may be con- centrtc, around Haversian canals; interstitial , between Haversian sys- tems; and circumferential, surrounding the bone. The canals connect the medullary cavity with the surface of the bone, allowing free permea- tion of blood-vessels. The lamellae may be stripped up as thin films, and seem bolted together by the perforating fibres of Sharpey. In thin plates of bone there are no Haversian canals, but lacunae and canaliculi are present. What is the arrangement of the vascular and nerve supply ? The arteries are periosteal, articular, and medullary (all are nutrient). The veins emerge from the bone in the same places that the arteries enter. Lymphatics accompany the vessels. Nerves enter with the arte- ries, and are destined for the vessels : none are known to end in bony tissue itself What is the purpose of the medullary cavity? To allow greater surface for muscular attachment with economy of weight ; for strength, a hollow cylinder being stronger than a solid one of same weight. In some water animals the bones are nearly solid, act- ing as ballast. In birds the bones are light, with large medullary cavities filled with warm air from the lungs. In the human subject there are air-cells in a few bones. 22 OSTEOLOGY. What are the physical and chemical characters of bone ? Bone consists one-third of animal matter, giving tenacity and elasticity, impregnated with earthy salts, two-thirds, in the form of minute gran- ules : this gives rigidity and brittleness. The analysis by Lehman is — Gelatin and blood-vessels, 33 per cent. Phosphate of calcium, 57 " Carbonate of calcium, 8 " Fluoride of calcium, 1 " Phosphate of magnesium, 1 " 100 per cent. Some add 1 per cent, of oily matter. Pure bone is thought to be a definite compound, whether from a child or old person : it differs in compactness and arrangement. The petrous portion of the temporal, and the long bones as a whole, have an excess of inorganic matter compared with bones of the trunk — the upper extremity more than the lower. In rickets the earthy matter may sink to 20 per cent. , instead of 66 per cent. Calcium phosphate forms more than half of bone and 88 per cent, of enamel of teeth. Bone is twice as strong as oak, three times as strong as elm, and twenty- two times as strong as freestone. A cubic inch will support 5000 pounds weight ; it requires 800 or 900 pounds to fracture the femur. What is the number of bones in the human skeleton ? 200 in the adult ; thus : K' P--- Total. r The vertebral column 26 . . 26 ..,,,, The skull - ... 6 8 22 Axial skeleton, ... ^ The hyoid bone 1 . . 1 [ The ribs and sternum 1 12 25 Amiendicular skeleton [ The upper limbs .32 64 Appenaicular skeleton, I ^j^^ j^^^^ jjj^^g ^ 3^ ^^ 34 83 200 The patella and pisiform are included, but not the ossicles of the ear or small sesamoid bones : the teeth belong to the epidermal layer. Into what classes are hones divisible? (1) Long or cylindrical^ about 90 in number; (2) tabular ov flat, for protection or muscular attachment, numbering 40 ; (3) sliort, for strength, numbering 30 ; (4) irregnlar, mostly situated symmetrically across the median plane of the body, numbering 40. Mention some terms used in descriptions. There are eminences and depressions, an articular and non-articular subdivision, of each variety. Articular eminences are called heads and condyles ; non-articular emi- BONES OF THE TRUNK. 23 nences are epicondyles, trochanters, tuberosities, tuherdes, spines, lines, apophyses, etc. An apophj^sis (excrescence) has never been separate from the surface of bone ; an epiphysis is developed from a separate centre. Certain adjectives used are — cHnoid, Hke a bed ; coracoid, Hke a crow's beak ; coronoid, the tip of a curve ; hamnlar, like a hook ; malleolar, like a mallet ; mastoid, like a nipple ; odontoid, like a tooth ; pterygoid, ^ like a wing ; spinous, thorn-like ; styloid, like a pen ; vaginal, ensheathing. Articular cavities are cotyloid, like a deep cup ; glenoid, like a shallow cup ; trochlear, pulley-like ; sigmoid,^ like the Greek letter for s. Non-articular cavities are fossae, sinuses, fissures, grooves, canals, hia- tuses, etc. BONES OF THE TRUNK. The clavicle and scapula do not belong to the trunk ; they form the shoulder girdle. The OS innominatum goes to form the pelvic girdle, completed behind by the sacrum, which belongs to the trunk. The animal tube is enclosed by the vertebral column ; the vegetative tube is in front of this and be- hind the hyoid bone and sternum. The parts of the trunk are the ver- tebral column, the sternum and ribs, the hyoid, and bones of the skull. THE VERTEBRAL, COLUMN. 1. The vertebral column is composed of a series of vertebrae (verto, to turn), originally thirty-three in number. The upper twenty-four reniai'n separate as movable or true vertebrae ; these are succeeded by five united into the sacrum ; then follow four dwindled segments united into the coccyx. These lower nine are the fixed or false vertebrae. * Beginning at the skull, there are seven cervical, twelve dorsal or thoracic connected with ribs, five abdominal or lumbar, five sacral, and four coccygeal vertebrae. The number in the cervical region is constant ; those between the dorsal and lumbar may vary reciprocally. If there are but eleven pairs of ribs, the twelfth dorsal vertebra will have lumbar characteristics; if thirteen pairs, the first lumbar will have dorsal cha- racteristics. A transitional lumbosacral vertebra, is met with, one side connected with the sacrum, the other having a free transverse process. Describe the characteristics of a vertebra. The first two cervical vertebrae are called rotation vertebrae ; all the other true ones, flexion vertebrae. A representative vertebra, like the tenth dorsal, presents a body for the purpose of support, an arch and spinal foramen for protection, and seven processes for leverage. The body or centrum, is a short cylinder ; the superior and inferior surfaces are flat, with a rim around the circumference. The front and sides are convex horizontally and concave from above down. The posterior surface is 24 BONES OF THE TRUNK. slightly concave from side to side, and marked by one or two venous foramina. The neural arch consists of two symmetrical portions meet- ing in the median plane behind. The anterior part or pedicle rises from a point on the body where the lateral and posterior surfaces meet ; the posterior part or lamina is broad and flat. The upper and lower borders of pedicles form vertebral notches, becoming intervertebral foramina -between contiguous vertebrae. The spinous process projects back from the junction of the two laminae. The transverse processes, one on either side, project outward from the arch at the junction of the pedicle with the lamina. The articular processes^ two superior and two inferior, project upward and ^wnward at the point of origin of the transverse processes. * ■ The foramen is bounded anteriorly by the body, posteriorly and later- ally by the arch; the series of rings thus formed constitutes the spinal canal. Describe a cenrfcal vertebra. The body is small and broad transversely ; the upper surface is con- cave from the upward projection of lateral lips, and is sloped down in front. The under surface is rounded at the sides and lipped anteriorly, so there is interlocking at the sides to prevent lateral displacement — an anterior lip to prevent posterior, and articular processes to prevent anterior, dislocations. The laminae are long and flat. The superior and inferior notches are nearly equal in depth. The spinous processes are short and bifid. The transverse processes are directed outward, down- ward, and forward, and present at their extremities an anterior and a posterior tubercle. Each process is grooved above, and perforated vertically at its base by the vertebrarterial foramen for a vein, artery, and plexus of nerves. This foramen is between the two roots of the process, the posterior corresponding to a dorsal transverse process, and the anterior to a rib. The articular processes are placed at the extremities of a short vertical column of bone ; the superior articular surface looks back and up. The foramen is triangular, and larger than in any other region. The peculiar cervical vertebrae are the first, second, and seventh. Describe the atlas. The atlas (supporting globe of head) has no body or spinous process, but is a large ring with articular and transverse processes. The pos- terior part of the ring corresponds to the neural canal of the other ver- tebrae ; the anterior part is occupied by the odontoid process of the axis. The anterior boundarj^ of the ring is the anterior arch, with a small tubercle in front for the longus colli muscle. Behind the tubercle is an articular surface for the odontoid. At the sides of the ring are the lateral masses bearing the superior and inferior articular processes. All the articular processes of the atlas and the superior ones of the axis are in front of the vertebral notches. The superior articular surfaces of the PLATE I. Fig. l.—To face page ^4- Ant. tub. of trans- verse process. For. for vertebral, artery. Pos. tub. of tr process. Transverse process. I process. ^) ^,^V^ Cervical Vertebra. ^*f>^ ^^V Fig. 2. — To face page 24- Tuber cle.- Biagram of section of odontoid process. Diagram of section of transverse ligament. For. for vertebral \artery. Groove for vertebral 'artery and 1st cervical nerve. Rudimentary spinous process. The Atlas. Fig. ^.— To face page 81. By 4 primary centimes. for body {8th week). Ifor each lamina (6th weeTc). PLATE II. Fig. 1. — To face 'page 26. Superior articular process.-. Demi-facet for head of rib. Facet for tubercle of rib. Demi-facet for head of rib. Inferior aHicular process. A Dorsal Vertebra, Fig. 2. — To face page 27. Superior articular process. Lumbar Vertebra. THE VERTEBRAL COLUMN. 25 atlas are oval and converge in front. The^^ look up and in, and form a cup for the occipital cond.yles. They may be partially subdivided by a transverse groove, and below the inner margin of each is a tubercle for the transverse ligament. The inferior articular surfaces are slightly con- vex, nearly circular, and do not wholly cover or fit the superior processes of the axis. The posterior arch presents in the median line either a ridge, hollow, or small tubercle. If a spinous process were well developed here, nodding of the head would be prevented. Just behind the lateral mass is a smooth sinus, the vertebral notch. The transverse processes are not bifid — are large and strong for attachment of rotatory muscles. Varieties, — The posterior or anterior bony arch may be incomplete ; the an- terior root of the transverse process may be ligamentous. A spicule of bone may bridge over the superior vertebral notch, and the canal formed be sub- divided by other spicules. The artery and vein go through the upper subdi- vision, the suboccipital nerve through the lower. Describe the axis. The second vertebra, vertebra dentata or epistropheus (to "turn round "), forms an axis upon which the atlas carrying the head rotates. The body of the atlas is joined upon that of the axis in form of a tooth- like process, the odontoid. Its apex is pointed, and just below is an en- largement or head, both giving attachment to bands of the check liga- ment. The process has in front a smooth articular surface for the arch of the atlas, and behind a smooth groove for the transverse ligament. This makes a slight constriction, but hardly a neck. The anterior surface of the body presents a slight ridge separating two depressions. The superior articular surface lies close to the odontoid, upon the body in part and upon the pedicles ; they look up and out. The inferior articular surfaces are behind the upper, and resemble corre- sponding ones in the cervical region. The spinous process is grooved inferiorly — is very large and bifid, in contradistinction to that of the atlas. The transverse processes are short, with the anterior tubercle nearly suppressed. The inferior vertebral notch is in front of the artic- ular surface, which is the rule for both notches below this in the column. Describe the seventh cervical vertebra. This has a long spinous process, non-bifurcated, tending to slope down, and projecting under the skin ; hence the name vertebra prominens. The transverse processes are massive, slightly grooved, with a small foramen or none at all ; the posterior tubercle is large and. the anterior one very small. The vertebral artery and vein do not pass through these for- amina : both veins may, sometimes the left artery does ; the vessels may enter no foramina till the fourth vertebra is reached. Varieties. — The spine of the sixth vertebra is not usually bifid ; in the negro this is the rule also for the third, fourth, and fifth. Bifurcation of spines is peculiar to the human skeleton. The anterior tubercle of the sixth is large, 26 BONES OF THE TRUNK. and called Chassaignac^s and carotid tubercle. The common carotid artery may be compressed against it : opposite this level the omo-hyoid crosses beneath the sterno-mastoid muscle ; the inferior thyroid artery crosses beneath the common carotid ; the cricoid cartilage is opposite, also the beginning of the tra- chea and oesophagus, the end of the larynx and pharynx. All known mammals have seven cervical vertebrae, except the sloth and manatee, which have six. There are two exceptions recorded in man. The number bears no relation to length of neck ; that of the whale and giraffe each contains seven. Describe the dorsal or thoracic vertebrae. The body is relatively small, and heart-shaped ; its antero-posterior and transverse diameters are nearly equal, and its depth is greater behind than in front. Where the arch joins the body there are articular sur- faces for the heads of ribs, generally two on each side, one at the upper and one at the lower border. Between the neck of a rib and transverse process is the costo-transverse foramen. In the cervical region this is represented by the vertebral foramen, and in the lumbar region the space is filled by the bony mass of the transverse process. The cross-section of a dorsal body shows a slight median projection for purposes of strength, similar to the linea aspera of the femur. The laminae are broad and flat and overlap each other. The superior vertebral notches are shallow or absent ; the inferior are deep. The spinous processes are bayonet-shaped, and terminate in a slight tubercle. They are longest and most oblique from the fifth to the eighth. The transverse processes are directed out and back, and terminate in a clubbed extremity, which presents an articular surface for the tuber- osity of a rib, and also two indistinct' tubercles, one from the upper and one from the lower border. The articular processes are nearly vertical, with their smooth surfaces (superior) looking back and out, the inferior in a reverse direction. The spinal foramen is nearly circular, and smaller than in other regions. What dorsal vertebrae present peculiar characters? The first, tenth, eleventh, and twelfth are to be distinguished. The Jirst dorsal resembles the seventh cervical. Its body above is trans- versely concave and lipped. The superior vertebral notches are deep, the superior articular processes are oblique, and the spinous process is nearly horizontal. On the side of the body, close to the upper border, is a whole facet for the first rib, and a very small demi-facet below for the second rib. The twelve ribs correspond to twelve joint surfaces, but these are di- vided, so that only the first, eleventh, and twelfth present single facets ; the first in addition has a half-facet, and the tenth has one demi-facet. THE VERTEBRAL COLUMN. 27 The upper demi-facets become larger on succeeding vertebrae, and when the eleventh is reached it is a complete facet. The tenth dorsal touches only one rib on a side, and has a nearly com- plete facet, mostly on the pedicle at its upper border. The transverse process has a small facet. The eleventh dorsal has one complete facet on each side, but none on the transverse process. The twelfth dorsal has a single facet on each side. The inferior articular surfaces turn out, resembling the lumbar verte- brae. The spinous process is short and nearly horizontal. The transverse processes are short, and present near their extremities the external^ superior^ and inferior tubercles^ which correspond respect- ively to the transverse^ inammillary^ and accessory processes of the lum- bar vertebrae. Rudiments of these tubercles may be seen on the tenth and eleventh vertebrae. The row of costal facets forms the anterior bor- der of the intervertebral foramina. The ribs in moving intrude some- what upon the vessels and nerves in those foramina; hence the "float- ing," most movable, ribs articulate with single vertebrae. The ninth dorsal may be lacking in the lower demi-facet; the eleventh may take the lumbar type of articular process. Describe the lumbar vertebrse. These are the largest of the movable vertebrae. They have no costal articular surfaces, and no foramina through the transverse processes. The body is reniform in outline, broad transversely, and deeper in front than behind. The laminae are short and thick, the superior notches shallow, the spinous process horizontal, and broad and thickened at its extremity. The transverse processes are slender and project directly out ; they are in front of the articular processes, and are considered to be homologous with the ribs. Their extremities lie in series with the external tubercles of the lower dorsal transverse processes. The accessory process (anapoph- ysis) lies behind each lumbar transverse process at its base, and points down. It is large in some animals, and locks the vertebrae together. The articular surfaces are vertical, the superior concave looking back and in : the superior are farther apart than the inferior, and embrace an inferior pair above them. The manimillary process [metapophysis) projects back from each su- perior articular process. The spinal foramen is triangular, larger than in the dorsal, and smaller than in the cervical regions. The fifth lumbar is massive, the inferior articular processes wider apart than the upper ; the transverse processes are broad and conical, and the laminae project into the spinal foramen. In the European the bodies of the lumbar vertebrae are collectively deeper in front than behind, but the individual segments vary. In the negro the depth of the five bodies is greater behind than in front. 28 fiONES Ot^ THE TRUNIC. FALSE VERTEBRA. Describe the sacral vertebrae. These in the adult form the os sacrum: it is placed between the two hip-bones, and with the coccyx completes the pelvic wall above and behind. The bone may be likened to a shovel in shape, and is wedge- shaped in four directions: (1) is narrower from side to side at its apex than at its base ; (2) is thinner antero-posteriorly at its apex than at its base ; (3) the dorsal surface is narrower than the anterior ; (4) a projec- tion into the articular surface of the ilium (Fig. 12). The bone presents anterior, posterior, and two lateral surfaces, a base, an apex, and a central canal for description. The ventral smface looks considerably downward, forming a projec- tion with the last lumbar, the sacro-vertehral angle of about 1 20°. this surface is concave from above down and from side to side, and is crossed by four horizontal ridges, indicating the union of five vertebrae. At the ends of the ridges are four anterior sacral foramina^ which lead ex- ternally into grooves on the lateral masses. The two rows of foramina are vertical and parallel, not approaching below, as the width of the bodies are all equal. The dorsal surface looks up and back, is convex and rough, and along the median line are three or four small spinous processes, more or less connected, forming a ridge. Below the ridge is a triangular opening, bounded by the imperfect laminae of the fourth and fifth sacral, and by the inferior articular processes of the last sacral, which are prolonged down into sacral cornua, meeting corresponding ones from the coccyx. On each side of the median ridge the united laminae are hollowed into the sacral groove, a continuation of the vertebral groove above ; next ex- ternally is a row of tubercles representing articular and mammillary pro- cesses ; next the four posterior sacral foramina, opposite to, but smaller than, the anterior. They correspond to the spaces between two transverse processes — the anterior to the spaces between two ribs. The lateral mass is that part external to the foramina, broad above and narrow below. It is made up of broadened transverse processes, rudiments of which are seen outside the posterior sacral foramina : the first pair are large ; the second are smaller and enter into the formation of the sacro-iliac joint ; the third, fourth, and fifth give attachment to ligaments. Anteriorly are four shallow grooves, separated by ridges, which give attachment to slips of the pyriformis. Above and externally the lateral mass shows an uneven auricular surface with its convexity forward ; it articulates with the ilium. Behind this the bone is still more rough for attachment of the posterior sacro-iliac ligament. The auric- ular surface rests on two and a half vertebrae, the larger part belonging to the first ; the upper three are therefore called the true sacral vertebrae, and the other two the caudal. Lower down the bone terminates in the inferior lateral angle, below which is a half-notch, forming a foramen with the coccyx for the fifth sacral nerve. FALSE VERTEBRA. 29 The base shows the reniform first sacral body, behind which is the triangular aperture of the sacral canal ; on each side of this is a large ar- ticular process bearing a large mammillary process. In front of this is a vertebral groove which helps form the last lumbar intervertebral fora- men. Externally is a modified transverse process, and in front of that a smooth triangular surface continuous with the iliac fossa, the ala of the sacrum. The apex is the body of the fifth sacral vertebra, transversely oval ; it articulates with the coccyx. The sacral canal curves with the bone, and becomes smaller as it descends. A transverse section is triangular above, but flattened and then semicircular below. From it there pass out four pairs of intervertebral foramina, opening anteriorly and pos- teriorly into the anterior and posterior sacral foramina, and closed ex- ternally by the lateral masses. The human sacrum is characterized by its great breadth compared to the length. The sacral index I :j — I in the male European is 112, negro 106, gorilla 72. The sacrum may consist of six pieces, or rarely of four. The bodies of the first and second may not be united, forming a second J " promontory " at this point. The sacral canal may be open more than usual or open throughout. What are the differences in the sacrum of the male and female ? In the female it is wider, sacral index 116, is less curved, the upper half nearly straight, is more oblique, and forms a more marked prom- ontory than in the male. Describe the coccygeal vertebrae. These are very rudimentary, usually four in number, often five, rarely three. Of the first one the pedicles and superior articular cornua project upward, and help form the last intervertebral foramen. The short transverse process usually bounds a notch for the anterior division of the fifth sacral nerve, or if it touches the inferior lateral angle of the sacrum, it forms a fifth anterior sacral foramen. The second vertebra has rudiments of transverse processes, and two small eminences in line with the cornua, representing the last traces of a neural arch. The third and fourth are mere nodules, and represent ver- tebral bodies only. In adult life the first piece is usually separate, and the other three united. All four may form one bone, which occurs oftener and earlier in the male. Steinbach observes that the male has most often five coccygeal vertebrae, and the female four or five with equal frequency. Describe the vertebral column as a whole. It is a central axis upon which other parts are arranged : above, it supports the head, laterally the ribs, and it rests on the hip-bones below. Its average length measured along the curves is 28 inches in the male, 30 BONES OF THE TRUNK. and 27 inches in the female ; persons seated in a row appear of about the same height. Viewed from the front, the column is formed of two pyramids applied base to base at the junction of the last lumbar with the sacrum. The upper pyramid can be divided into three — viz. the six lower cervical, with base at first dorsal ; the second is inverted, with the apex at fourth dor- sal ; and the third commences at the fourth dorsal and ends at the last lumbar. All three diameters of the vertebrae increase from the third cervical to the last lumbar : vertical diameter from f-lj inches (14 mm. to 29 mm.), sagittal from f-lf inches (14 mm. to 35 mm.), transverse (does not increase in dorsal region) from |-2J inches (21 mm. to 55 mm. ). The column presents a lateral curve convex to the right : this may be an indentation on the left side rather than a curve. Three theories are proposed: (1) liver draws right side over; (2) pulsating aorta pushes column over ; (3) right-handedness. The last is most tenable. V iewed laterally, there are four curves, alternately convex and concave, the cervical, dorsal, lumbar, and pelvic; the first extends from the odon- toid to the second dorsal; the dorsal curve is concave forward and ends at the twelfth dorsal; the lumbar ends at the sacro- vertebral angle, and the pelvic ends at the tip of the coccyx. The dorsal and pelvic curves are primary, exist at birth, enter into the formation of* bone-walled cavities, and are due to the conformation of the 'vertebral bodies. The dorsal is produced by pressure of viscera and weight of head and thorax. ^ • When the child begins to walk the ilio- psoas muscles pull the lumbar vertebrae forward, producing here and in the cervical region secondary or compensatory curves, mainly due to the shape of the intervertebral disks.* Sitting and the weight of the head also induce the cervical curve. The pathological curvatures are called 7a/phosis (humpbacked), scolio- sis (crooked, bent to one side), and lordosis^ (bent forward). Posteriorly, the spines occupy the median line or may be normally twisted a little from it. In the cervical region they are short, horizontal, and bifid ; in the dorsal they are oblique above, vertical in the mid por- tion, and horizontal below ; in the lumbar they are horizontal. A cross- section of a cervical spine is semilunar ; of a dorsal, triangular ; of a lumbar, oblong. On either side of the spines is the vertebral groove, bounded externally in the cervical and dorsal region by the transverse processes, and in the lumbar by the mammillary processes. The trans- verse processes of the atlas are long ; of the axis, short, increasing to the first dorsal, thence diminishing to the last dorsal, and beconiing suddenly much longer in the lumbar vertebrae. In the cervical region the trans- verse processes are in front of articular processes and between interver- tebral foramina. In the dorsal region they are behind both. In the lumbar region they are in front of the articular processes and behind the intervertebral foramina. Intervertebral foramina are always in front of articular processes, ex- cept those of the atlas and the upper ones of the axis. They are named THE THORAX. 31 from the upper of the two vertebrae which go to form them, excepting in the cervical region, where there are eight, the fissure between the skull and atlas being called the first. In the cervical region the superior articular surfaces look back and up. In the dorsal region the superior articular surfaces look back and out. In the lumbar region the superior articular surfaces look back and in. The inferior surfaces have an opposite direction. The spinal canal has three sets of openings into it, the two rows of the intervertebral foramina and the intervertebral fissures between the laminae. It is naiTowest in those parts having least motion — viz. in the dorsal and sacral regions. It is round and f inch (17 mm.) in diameter in the dorsal region ; is triangular with apex behind in the cervical and lumbar regions ; and largest of all in the cervical. OSSIFICATION OP THE VERTEBRA. Each vertebra is developed from three primary centres — one on each side for the lamina and processes, appearing at the sikth week of foetal life, and one for the body at the eighth week. Five secondary centres are added — three for the tips of the spinous and transverse processes, and two for thin annular plates on the circumferences of the upper and lower surfaces of the bodies. These are not united till the twenty-fifth year. A lumbar vertebra has two others for the mammillary processes. The atlas has three primary centres, the axis, six ; there are two lateral ones for the odontoid, between which a bit of cartilage remains till advanced life ; the apex of the odontoid has a separate centre. The seventh cervical usually has a separate centre in the anterior part of its transverse process, and likewise the first lumbar, though infrequently. The ossification of the laminae proceeds from above down, explaining the occurrence of spina bifida in the lower part of the column : ossification of the bodies appears first in the last dorsal and extends in both directions. The sacrum as a whole is developed from thirty-five centres — fifteen for bodies and arches, ten for epiphysial plates, three for the upper part of each lateral mass, and two for an auricular surface and thin edge below. The coccyx has four centres — one for each piece, sometimes two for the first one. THE THORAX. The skeleton of the thorax comprises the dorsal vertebrae, the ster- num, ribs, and costal cartilages. Describe the sternum. The breast-bone is an azygos bone in the median Hne at the front of the chest. It has attached the clavicles and seven upper costal carti- lages. It originally consisted of six segments, and is likened to a sword. The upper segment remains distinct as the manubrium or handle; the next four fuse into the bo^y or gladiolus (little sword) ; the sixth por- tion is the ensiform or xiphoid jwocess (sword-like). The sternum is flattened from before backward, and curved with a slight convexity, to the front. It is broad above, then narrow to the beginning of the gladiolus, then broad again, and narrow at the ensi- 32 BONES OF THE TRUNK. form. The bone contains red marrow, confined in cancellous tissue be- tween two thin layers of compact bone. The manubrium (presternum) is the thickest part, concavo-convex on cross-section. Superiorly are three deep notches : the middle one is the semilunar or interclavicular notch ; the lateral ones look up back and out for articulation with the clavicles. Below the lateral notches on either side is a rough triangular surface for union with the first costal cartilage ; next is a sloping concave surface ; and at the lower angle a half notch for the second rib. The junction of the manubrium with the gladiolus is always prominent, and serves as a landmark for the second rib. The body (mesosternum) is marked anteriorly by three slight trans- verse ridges. Each lateral margin presents four notches and two half- notches : they approach each other from above down. The half-notch above is for the second cartilage ; the notches^ for the third, fourth, and fifth cartilages are opposite the lines of junction of the four segments ; the notch for the sixth cartilage and the half-notch for the seventh be- long to the inferior segment. "So most of the cartilages of the true ribs articulate in front at junctions of segments, analogous to the connection of ribs with the vertebral column. The ensiform 'process (metasternum) projects down between the carti- lages of the seventh rib. It has various forms — may be bent forward, backward, or laterally, be forked or perforated, and is more or less carti- laginous. At its upper angle is a half-notch for the seventh cartilage. The sternum is subcutaneous in the median line, forming the floor of the sternal groove^ with the supra- or episternal notch above and the iiifra- sternal depression at the ensiform process. The body of the male sternum is more than twice as long as the manu- brium; in the female it is less than twice the same length. The body at the junction of the third and fourth segments may be perforated by a sternal foramen, or rarely by a sternal fissure. Two small nodules, ossa suprasternalia, are sometimes found close inside the clavicular notches: they represent an episternal bone of lower animals, other remains of which are the interartic- ular fibro-cartilage of the sterno-clavicular joint. In flying birds a great keel exists along the middle of the sternum. In the male wild swan and guinea- fowl the sternum is tunnelled and contains the trachea. Describe the general characters of the ribs. The ribs (costae) are twelve in number on each side. The first seven pairs, attached by costal cartilages to the sternum, are called sternal^ true, or vertebrosternal ribs ; the remaining five pairs are asternal or false ribs : each of the upper three pairs of false ribs has its cartilage attached to the cartilage above it, vertebro-chondral ; the last two pairs have no such attachment, and slyo floating o{ vertebral ribs. Each rib presents three parts— a body, an anterior and a posterior extremity. The posterior extremity is thickened into the head or capitulum : it has a superior and an inferior articular facet for articulation with two THE THORAX. 33 vertebrae ; the lower is the larger, and between them is a ridge for the interarticular cartilage. Next externally is the flattened neck^ 1 inch long (collum costae), and next the tuberosity^ divided into two parts by an oblique groove. The inner and lower part is articular for the transverse process of the lower of the two vertebrae, with which the rib is connected ; the outer and upper part is rough for the posterior costotransverse ligament. The body is laterally compressed, and over its most convex part is a rough line corresponding to the outer border of the sacro-lumbalis mus- cle, marking the angle; still farther forward is another line, the anterior angle. The inferior border presents the subcostal groove, best marked at the angle and disappearing in front ; it lodges intercostal vessels and nerves. Starting from the upper and inner border of the neck is a su- perior costal groove soon lost on the body. The anterior extremity is hollowed into a pit for union with the costal cartilage. The ribs are curved on three axes — a vertical one near the angle ; also a transverse one at this place, ^o that when the anterior part of the rib is horizontal the posterior will rise up ; and a longitudinal one, so that the anterior part looks up and the posterior part looks down. The upper ribs are nearly at right angles with the spine, and reach their greatest obliquity at the ninth. The seventh or eighth rib is the longest, after which they decrease to the twelfth. The first is broadest, and the twelfth narrowest. The distance from the angle to the tuberosity in- creases from above down. Describe the peculiar ribs. The first rib is not twisted, and its surfaces look nearly up and down. The head is small and has a single articular facet : the neck is slender, and the angle coincides with the tuberosity. ^ On the upper surface is a rough impression for the scalenus medius muscle, and in front of that two smooth depressions with an intervening ridge : the posterior depression is for the "third portion " of the subclavian artery, the ridge ending in the scalene tubercle (Lisfranc's tubercle) is for the attachment of the scalenus anticus muscle, and the anterior depression for the subclavian vein. There is no subcostal groove. « The second rib is not twisted and has no angle (Henle) : it presents near the middle depressions for the scalenus posticus and serratus mag- nus muscles. It has a double articular facet. The eleventh and twelfth ribs have single articular facets, and only slight elevations to mark the tuberosities which do not articulate with the transverse process- The eleventh has a slight subcostal groove ; the twelfth has no angle. The number of ribs may be thirteen on one or both sides ; the gorilla and chimpanzee have each thirteen pairs of ribs. The added rib is most often connected with the first lumbar transverse process, sometimes with the seventh cervical vertebra, where it has a double attachment— viz. to the body and to the transverse process. The pleura descends to the same spot whether 3— A. 34 BONES OF THE TRUNK. the twelfth rib be absent or not. The tenth rib may have but one articular facet. The twelfth rib varies in length from 8 inches to less than 1 inch. Describe the costal cartilages. They prolong the ribs to the sternum. Their breadth diminishes from tlie first to the last ; they become narrow toward their sternal extrem- ities ; their length increases to the seventh ; the first descends a little, the second is horizontal, the others, except the last two, ascend after following the direction of the rib for a short distance. Their external extremities are convex, and planted into the osseous tissue of correspond- ing ribs. The inner extremity of the first is united directly to the sternum without articular cavity; the succeeding six have rounded extremities for the sternal notches. Each cartilage of the first three false ribs is united to the lower border of the one above it. The fifth, sixth, seventh, and eighth cartilages articulate with each other ; the eleventh and twelfth are pointed and unattached. The eighth may articulate with the sternum. The seventh may meet its fellow of the other side in front of the ensiform. There may be no articula- tion between the fifth and sixth ; there may be one between the eighth and ninth. Describe the thorax as a whole. The bony thorax is conical, and flattened from before backward. The short an tero- posterior diameter is characteristic of man, but in the lower mammals and human foetus it is longer than the transverse diameter. The posterior wall is convex forward, and a broad furrow on either side, the sulcus pulmoncdis, is formed by the ribs as they project backward, so that the weight of the body is more equally distributed around the column. The anterior wall is convex and at an angle of 20°-25° with the pos- terior. A horizontal antero-posterior diameter from the base of the ensiform is 8 inches (20 cm. ) ; the transverse at the eighth or ninth rib is 11 inches (28 cm.) ; the vertical anteriorly is 6 inches (15.5 cm.), and posteriorly iiPl2 inches (31.5 cm.). The upper border of the sternum is opposite the lower edge of the second dorsal (Henle), and the lower border oppo- site the tenth dorsal. The sides slope out to the ninth rib. The upper aperture is contracted and reniform, and sloped downward ; the lower is irregular, and its margin ascends on each side from the tenth rib to the ensiform, forming the suhcostal angle. The intercostal spaces are wider above than below. The sternum is developed from six centres, one for each segment : the first to appear is at the sixth month in the manubrium ; the ensiform centre does not appear till the sixth year. The manubrium may have two or more centres, and the third, fourth, and fifth segments may have two centres, each placed laterally : if the bony parts formed from these do not meet, there is left the sternal foramen or fissure. The manubrium and body exception- BONES OF THE HEAD. 35 ally join by bone, and usually remain separate till the twenty-fifth year. The ensiform unites in middle life. A single centre, situated posteriorly, appears for each rib at the eighth week ; after puberty two secondary centres appeal- in the cartilage of the head and tuberosity. The eleventh and twelfth ribs have none for the tuberosity. In the adult the first costal cartilage usually shows superficial ossification or even a complete bony sheath. In advanced life the other cartilages may be covered by bone, especially* anteriorly : this tendency is stronger in the male. The cartilage itself is seldom ossified. THE HYOID BONE. Describe the hyoid bone. The hyoid, or os hnguae, is situated at the base of the tongue opposite the second or third cervical vertebra, and is shaped Uke the Greek let- ter iipsilon. Its body is compressed from above down ; the anterior sur- face looks up and forward, and is marked by a crucial ridge with a tubercle in the centre and depressions on either side for muscular at- tachment. Its posterior surface is concave and faces the epiglottis. The great cormia project back and are flat from above down. After middle life they have bony union with the bod3\ The small cornua are short and conical, and project up and back from the junctions of the great cornua and body ; they give attachment to the stylo-hyoid liga- ments and have synovial articulations with the body. There are five centres of ossification for the five parts. BONES OP THE HEAD. The skull is divided into two parts, the cranium amd/ace : the former protects the brain ; the face surrounds the mouth, nasal cavities, and orbits in part. Face has fourteen bones. (a) unpairing : Vomer, Cranium has eight bones. (a) unpairing : ih) pairing: Occipital, Sphenoid, Ethmoid, Frontal. Temporal, Parietal. {b) pairing: Inferior maxilla. Superior maxilla, Palate, Lachiymal, Inferior turbinate. Nasal, Malar. BONES OF THE CRANIUM. Describe the occipital bone. This bone (ob. caput, against the head) is flattened, lozenge-shaped, and bent on itself; the upper anterior surface is concave, the posterior 36 BONES OF THE HEAD. is convex. It articulates with six bones — two parietal, two temporal, the sphenoid and atlas. Below and in front the bone is pierced by the foramen magnum (for. occipitale) for the passage of the spinal cord and membranes, spinal por- tions of the spinal accessory nerves, and two vertebral arteries : the part behind the foramen is the tabular portion, in front is the basilar por- tion, at the sides are the condylar portions. The superior borders with the parietals form the lambdoid suture ; the inferior borders from the lateral angles to the jugular processes articulate with the mastoid, thence with the petrous portion of the temporal; the basilar unites with the sphenoid by cartilage or by bone. The rhombic form may become eight-sided by secondary obtuse angles between the upper and lateral, the lateral and lower angles. The tabular portion presents posteriorly near the centre the external occipital protuberance, from which the superior curved line arches outward on each side to the lateral angles ; a little above this may usually be seen the highest or supreme curved line. Below the protuberance is a median external occipitcd crest, from the centre of which passes out the inferior curved line to the jugular processes. To the supreme curved line is the bony attachment of the epicranial apo- neurosis ; to the superior curved line, most internally, the biventer cervicis, for the inner third the trapezius, next the occipitalis, sterno-cleido-mastoid, and splenius capitis. Between the superior and inferior lines are internally a large impression for the complexus, and externally a small one for the supe- rior oblique. Below the lower line is an inner impression for the rect. cap. post, minor, and an outer one for the major. The ligamentum uuchse is at- tached to the protuberance and crest. The deep surface of the tabular portion shows two ridges crossing each other, one from the upper angle to the foramen magnum, one connect- ing the two lateral angles. Where these intersect is the internal occi- pital protuberance, not always opposite the external. The ridges mark oif four hollows, the superior and inferior occipital fossae, which lodge the posterior cerebral and the cerebellar lobes. The ridges are grooved for venous sinuses. The space where the longitudinal sinus is continued into a lateral one, generally the right, lodges the torcidccr Herophili (wine-press of Herophilus). Below this the vertical ridge is sharp, and named the internal occipital crest. The condylar jwrtions bear the articular surfaces for the atlas : these condyles converge toward the front, are doubly convex, and somewhat everted. At the inner side of each is a rough impression for a lateral odontoid ligament. Perforating the condyle from within out is the an- terior condylar foramen for the hypoglossal nerve and a branch of the ascending pharyngeal artery. Immediately above this foramen is a heap- ing up of bone designated as the eminentia innominata. Behind the condyle is a posterior condylar fossa : it may be perforated by a foramen for the passage of a vein from the lateral sinus ; both fossa and foramen are inconstant. External to the condyle is the jugular process, analogue BONES OF THE CRANIUM. 37 of a transverse process : it lies above the transverse process of the atlas, and it presents in front the jugular notch^ which helps form the jugular foramen ; the right notch is usually the larger. The extremit}^ of the process presents an irregular facet for union with the temporal bone ; this union is osseous at the twenty-fifth year. The upper surface presents the end of the lateral sulcus leading to the jugular notch : here the posterior condylar foramen opens if i)resent. On the under surface is attached the rect. cap. lateralis muscle. The basilar 2yi'ocess projects forward and upward in the middle of the base of the skull and at the top of the pharynx, increasing in thickness and diminishing in width. Superiorly is a basilar groove for the medulla, and at either lateral margin a shallow sulcus for the inferior petrosal sinus. Inferiorly in the middle line is the 2)]iaryngeal tubercle for aponeurotic attachment of the superior constrictor of the pharynx : on each side of it are attached the rect. cap. anticus major and minor muscles. The portion of bone above the superior curved line (intraparietal) is some- times separated from the rest by a transverse suture. The bone between the supreme and superior curved lines may be very prominent and constitute the torus occipitalis transversus (transverse bulge). An intrajugular process may project into the jugular notch. From the under aspect of the jugular process the paramastoid process may descend to the transverse process of the atlas. There is a rare articulation between the basilar process and anterior arch of the atlas or odontoid. Birds and reptiles have only a single occipital condyle, placed in front of the foramen magnum. The external occipital crest is greatly developed in most animals. Describe the parietal bone. This bone is quadrilateral, convex externally and concave internally, a little broader above than below. It articulates with five bones — the opposite parietal, the occipital, frontal, sphenoid, and temporal. Near the middle of the outer surface, nearer the lower than upper border, is the parietal eminence or boss. This is very prominent in young bones. Through or just below this are the superior and inferior temporal lines, f inch apart: to the superior one is attached the temporal fascia, to the inferior the temporal muscle. The inferior line does not pass off the parietal upon the occipital bone ; below it is the temporal surface for origin of the temporal muscle. Near the upper border, and f inch (20 mm.) from the posterior angle, is the parietal foramen for the exit of a vein, and usually entrance of a branch of the occipital artery. The sagittal suture between the two parietal foramina is inclined to oblite- ration. The deepest part of the inner surface opposite the parietal eminence is the parietal fossa. The inner surface is marked by furrows or canals for the meningeal vessels. A slight depression runs along the superior border, forming part of the sulcus for the longitudinal sinus. At the posterior inferior angle is a groove for the lateral sinus, which first runs 38 BONES OF THE HEAD. across the occipital, then this angle of the parietal, then the mastoid por- tion of the temporal, and finally the jugular process of the occipital. Near the upper border of the bone are digital depressions for the lodg- ment of Pacchionian bodies (modified tufts of arachnoid membrane). The anterior border is alternately bevelled, so that the frontal rests upon it above and the parietal overlaps the frontal below, thus resisting the usual directions of violence. The inferior border is flattened and squamous, and divided into three parts, named from the bones over- lapping it, sphenoid, squamous, and mastoid from before backward. The parietal foramen may be absent on one or both sides or may be very large. This bone is bipartite iu some Australian skulls. Describe the frontal bone. The frontal {frons, forehead) arches up and back above the orbits, forming the fore part of the cranium. It articulates with twelve bones — the parietals and sphenoid, the malars, the nasals, superior maxillse, lachrymals, and ethmoid. Inferiorly are two thin horizontal laminae, the orbital plates, forming the roof of the orbits and separated by tlie ethmoidal notch. Three surfaces are presented for description. The anterior surface shows the greatest convexity on each side in the frontal eminence, separated by a slight depression below from the superciliary ridge, just above the orbit. In the middle line between the two ridges is a smooth surface, the glabella (without hair), also called nasal emi- nence. The orbital arch ends in extremities called the internal and external angular processes : the internal is slightly marked, and articu- lates with the lachrymal bone ; the external is prominent, and articulates with the malar. At the junction of the inner and middle third of the arch is the supraorbital notch or foramen for the supraorbital nerve and vessels. The temporal crest springs from the outer angular process, and is continuous with the inferior temporal line on the parietal. Inferior Surface. — The orbital plates are somewhat triangular, with their internal margins parallel. Close to the external angular process is the lachrymal fossa, and close to the inner process is the trochlear fossa for the pulley of the superior oblique. Between the internal an- gular processes is the nasal notch, and from its concavity the nasal process projects beneath the nasal bones and nasal processes of the superior maxillae and supports the bridge of the nose. On the posterior surface of this process are two grooves which enter into the roof of the nasal fossae ; between the grooves is a median ridge, the nasal spine, which descends in the septum of the nose above the perpendicular plate of the ethmoid. Along the inner margins of the ethmoidal notch are irregular depressions forming the roof of cells in the ethmoid. Each border is marked inferiorly by two grooves, completing with the ethmoid the anterior smd posterior internal orbital canals : the anterior transmits the nasal nerve from the orbit and anterior ethmoidal vessels j the pos- terior transmits the posterior ethmoidal vessels. The frontal sinus opens BONES OF THE CRANIUM. 39 at the root of the nasal process. It is between the outer and inner tables, over the root of the nose and divided by a bony septum. Out- side and behind the orbital surface is a rough triangular area for articu- lation with the great wing of the sphenoid. Cerebral Surface. — This forms a large concavity for the anterior lobes of the cerebrum. The orbital plates are convex and marked by ridges and depressions, and are so thin as to be transparent : these plates make an angle of about 60° with the upper part of the bone. From the upper margin descends the frontal sulcus, running into the frontal crest at the lower margin. At the base of the crest is usually a groove converted into the foramen cwcvm by the approximation of the ethmoid ; this is usually open in children, but blind in adults. The sides of this surface present grooves for the meningeal vessels. The thin transverse edge bounding the surface behind articulates with the greater and lesser wings of the sphenoid. The trochlear fossa may be absent or have in addition a trochlear spine. The bone may be divided by the frontal or metopic suture, the infantile halves having failed to unite : this occurs in 8 per cent, of European skulls, 5 per cent, of Mongolian, and 1 per cent, of African. A trace of the suture is seen in nearly all adult frontal bones just above the nasal notch. Describe the temporal bone. The temporal bone (tempus, time, as hair first becomes gray in this region, indicating age) helps form the side and base of the skull and con- tains the organ of hearing. It presents four parts — the squamous, mas- toid, and pyramidal y which includes the petrous and tympanic. It ar- ticulates with five bones — posteriorly and internally with the occipital, above with the parietal, in front with the sphenoid and malar, and below with the inferior maxilla. The squamous portion (scale), or squamo-zygomatic, presents a vertical portion and a narrow horizontal portion at the base of the skull. It is limited above by an arched border describing two-thirds of a circle. The outer surface is vertical, with a slight convexity, and forms part of the temporal fossa. This portion overlaps the mastoid. Above the aperture of the ear is a vertical groove for the middle temporal artery. The zygoma is connected with the lower and outer part of the squa- mous portion : it is broad at its base, with surfaces looking up and down ; it then twists on itself, so that it has inner and outer surfaces, upper and lower borders. The upper border is thin and longer than the inferior, which is short and arched ; the anterior extremity articulates with the malar. The zygoma is attached by two roots : the anterior, continuous with the lower border, is a broad convex ridge directed inward, called the eminentia articularis. At the junction of this with the zygoma is a tubercle for the external lateral ligament of the lower jaw. The poste- rior root prolongs the upper border of the zygoma as the supramastoid crest, which becomes continuous with the lower temporal line ; it is above the suture between the squama and mastoid. Between the two roots is 40 BONES OF THE HEAD. the glenoid fossa : its articular portion is bounded behind by the post- glenoid process, sometimes called the middle root of the zj^goma. It is strongly developed in some mammals to prevent posterior dislocation of the lower jaw. The inferior aspect of the horizontal portion presents three districts — the auricular, articular, and zygomatic, from behind forward. The auricular part forms the upper concave margin of the external auditory meatus and a part of the roof of the external ear. The next portion is the glenoid fossa, which is divided into two parts by the transverse fissure of Glaser. The posterior part is non-articular, formed by the tympanic plate and lodging part of the parotid gland. The anterior part of the fossa is. articular, bounded behind by the post- glenoid process and in front by the eminentia articularis ; it is the fossa mandibular i^, concavo-convex for the condyle of the lower jaw. The fissure of Glaser is a double cleft. The first fissure behind the artic- ular fossa is the petro-squamous (fps, Fig. 1), next comes a narrow pro- jection of the tegmen tympani (tt^) from the petrous, and next the petro-tympanic fissure or Glaserian fissure proper : it lodges the slender process of the malleus and tympanic branch of the internal maxillary artery. Farther in, and external to the Eustachian tube, is the canal of Huguier, by which the chorda tympani nerve enters. The outer part of the Grlaserian fissure is entirely closed. Sometimes a " false jugular foramen " is present in the squamous, by which, in the embryo and many animals, blood flows from the cranium to the exter- nal jugular vein. It is between the articular fossa and external auditory meatus. In front of the articular eminence, and separated by a slight ridge from the temporal surface, is a small triangular infratemporal surface, entering into the zygomatic fossa. The inner surface of the squamous is concave and presents cerebral impressions and meningeal grooves. A narrow horizontal part helps form the anterior wall of the tympanum. y The superior border is thin and fluted, and overlaps the parietal bone. The parietal notch marks the junction of the superior border with the mastoid : the squamo-mastoid suture passes from this notch to the poste- rior edge of the external auditory meatus. The antero-inferior border is thick, and bevelled above continuously with the upper border at the expense of the inner surface, below at the expense of the outer — all for articulation with the great wing of the sphenoid. The mastoid portion (teat-like) is rough for muscular attachment, and prolonged down behind the auditory meatus as the mastoid process. At the posterior border is the mastoid foramen, sometimes foramina, trans- mitting veins from the lateral sinus and a mastoid artery from the occip- ital : the foramen is inconstant, and may be in the occipital bone or in the masto-occipital suture. On the inner side of the mastoid process is the digastric fossa for attachment of the posterior belly of the digastric, BONES OF THE CRANIUM. 41 and internal to this is the sulcus occipitalis for lodgment of the occipital artery. The internal surface shows the fossa sigmoidea, which is a part of the sulcus for the lateral sinus : the mastoid foramen opens into it. A sec- tion of the mastoid portion shows a number of communicating cells ; be- low in the mastoid process they are developed after puberty and are arranged vertically. Above these is the antrum mastoideum, which is a horizontal cellular cavity, a part of the middle ear : its roof and postero- lateral wall is formed from the petrous portion, and is continuous with the roof and side of the tympanum. Its antero-median wall belongs to the mastoid. Below it connects with the mastoid cells : its opening into the tympanum is large and on a level with the foramen ovale, so the floor of the tympanum passes in front into the Eustachian tube and behind into the mastoid antrum. The sujKrior border of the mastoid is rough, slopes back, and articulates with the postero-inferior angle of the parietal : the posterior border articulates with the occipital between its lateral angle and jugular process. The pyramidal portion includes the petrous (stone) and tympanic (drum). The petrous portion is a four-sided pyramid with its base turned out, and its long axis inward, forward, and slightly downward. The axes of the two portions if prolonged w^ould meet at the posterior edge of the nasal septum. This portion presents four borders — superior, inferior J anterior, and posterior; and four surfaces — antero-internal Ftg. 1. (lA, Fig. 1), postero-internal (ip), antero-external (ea), and postero-ex- ternal (ep) ; also a base and an apex. The base is concealed in its upper half by the squamous and mastoid, and covered below, where these diverge, by the tj^mpanic portion. The apex is received into the angle between the great wing of the sphenoid and the basilar process, and pre- 42 BONES OF THE HEAD. sents the anterior orifice of the carotid canal, and forms the postero-ex- ternal boundary of the foramen lacerum. The antero-interrial surface is in the middle fossa of the skull, and separated from the squamous portion by the fissura petro-squamosa (fps). This surface presents a little behind its centre the eminentia arciiata, covering the superior semicircular canal ; in front of this is a groove leading to the hiatus Fallopu, which leads to the aqueduct of Fallopius ; it transmits the large superficial petrosal nerve and the pe- trosal branch of the middle meningeal artery. Outside this is a groove and small foramen for the small superficial petrosal nerve. Near the apex the wall of the carotid canal is deficient ; above this is a shallow depression for the Gasserian ganglion. Between the petro-squamous fissure externally and the hiatus Fallopii and eminence of the superior semicircular canal internally is a thin lamina which roofs in the tym- panum and a common canal for the Eustachian tube and tensor tympani muscle : it is the tegmeii tympani^ tt^, a process of the petrous. The postero-internal surface is in the posterior fossa of the skull, and continuous with the inner surface of the mastoid. Near the centre, but nearer the upper than the lower bor- FiG. 2. der, is a large orifice, the porus acust. mrRLL. flft.cRiB.sup. int.^ leading into a canal J inch (6 mm. ) \.-«!mZ loi^oj which is the internal auditory ^^^^k meatus ; this is terminated by the lam- tfff/sn? /wir//^-^^^^^^ 2*?ia crihrosa (Fig. 2). A transverse poit.uMTcoc/fr^^^^m^^^ Tidgc, cruta jalcijormis^ separates a ^^^^ /W.5/-W. small superior from a large inferior TMCT.sFtR.Fo/ffrM. fossa. A faiut perpendicular crest di- vides these into four fossae. The facial nerve enters the aqueduct of Fallopius in the upper anterior fossa ; the area crihrosa superior is the perforated part of the upper posterior fossa for auditory nerves going to the utricle, superior, and external auditory canals; below this is the area crihrosa media, conveying an auditory branch to the saccule ; also the foramen singulare for a branch to the posterior auditory canal ; in the lower anterior fossa is the tractus spiralis foraminulentus, for the cochlear division of the auditory nerve,, ending at the foramen centrale cocJilece. Behind the auditory meatus is a small slit, the opening of the aque- duct of the vestihule, transmitting a small artery and vein and lodging a process of dura mater which encloses the saccus endolymphaiicus ; above and between these is a depression or fissure, the suharcuate fossa, which extends into the arch of the superior semicircular canal and represerfts the floccular fossa of animals. The postero-external surface forms part of the base of the skull. Beginning at the apex, is first a quadrilateral surface for the origin of the levator palati and tensor tympani muscles, the lower aperture of the carotid canal, which is first vertical and then horizontal ; vertically be- BONES OF THE CRANIUM. 43 neath the internal auditory meatus is the three-sided opening of the aqueduct of the cochlea, which in early life transmits a vein ; next be- hind is the jugular fossa, which forms the jugular foramen when oppo- site the jugular notch of the occipital. In front of the bony ridge, between the carotid canal and jugular fossa, is a small foramen for Jacohso7is nerve (from the glosso-pharyn- geal) to the tympanic plexus ; this foramen usually splits to give exit to the small deep petrosal [carotico-tympanicus superior) from the tym- panic to the carotid plexus. Externally in the ascending part of the carotid canal is a small foramen for the carotico-tympamcus inferior, a sympathetic nerve going from the carotid plexus to the tympanic. On the outside of the jugular fossa is a foraraen for Arnold's nerve from the pneumogastric : its canal runs through the petrous transversely and out, and splits into two, an inner to meet the facial canal, ^ inch (5 to 6 mm.) above the stylo-mastoid foramen, and the other to open at the tympanico- mastoid (auricular) fissure. Behind the jugular fossa is the jugular facet, 'for articulation by syn- chondrosis with the jugular process of the occipital. Externally is the styloid process, enclosed between the layers of the vaginal process. It gives attachment to three muscles and two ligaments. Between the sty- loid and mastoid processes is the stylo-mastoid foramen, the end of the aqueductus Fallopii, which passes first out and back over the labyrinth, then in and back, and then down to terminate here : the stylo-mastoid artery enters this foramen. The antero-external surface is free anteriorly for a short distance, and articulates with the great wing of the sphenoid ; posteriorly it is con- cealed by the tympanic plate (pt. Fig. 1). At the angle between the squamous and petrous portions is the open- ing of a canal the musculo-tubarius (cm), incompletely divided into two by a projecting lamella, the cochleariform process or septum tuhce (STU). The upper groove is for the tensor tympani muscle, and the lower is the bony wall of the Eustachian tube. This common canal is covered by the tegmen, its inner wall is the antero-external surface of the petrous, and its floor and outer wall are the tympanic plate. The septum tubse rarely reaches the opposite wall, and rises from the anterior wall of the carot!id canal (cca). This wall is made of two thin lamellae with diploe between, in which runs the small deep petrosal nerve. The superior harder is grooved for the superior petrosal sinus, and gives attachment to the tentorium cerebelli. The posterior border presents on its inner portion a half groove for the inferior petrosal sinus, and externally the margin of the jugular fossa. From the apex, where a bony projection often overhangs the inferior petrosal groove, a fibrous band, the petro- sphenoidal ligament, extends to the side of the dorsum sellae, and com- pletes a foramen for the inferior petrosal sinus and sixth nerve. The anterior harder has two parts — an outer, forming the petro-squamous fissure, and an inner free portion to form the petro-sphenoidal suture. The inferior harder is largely concealed by the tympanic and petrous 44 BONES OF THE HEAD. portions: near the apex it is indistinct, and here the bone is rather three-sided. The tympanic portion is beneath the petrous and between the mas- toid and squamous. At birth it is a ring from which is developed the tym- panic plate. The thickened outer extremity of this plate is the external auditory process^ a curved, uneven lamina forming the anterior and in- ferior wall of the external auditory meatus and t^^mpanum. The upper margin of the plate is concealed by the petrous and forms the posterior boundary of the fissure of Glaser. Its lower margin descends as a sharp edge, the vaginal process : it is continuous with the inferior border of the petrous portion. Describe the sphenoid. The sphenoid bone (wedge-like) is placed across the base of the skull near its middle, and binds the other cranial bones together. It helps form the cavities of the cranium, orbits, and nasal fossa3, and has to do with six pairs of cranial nerves. It resembles a bat with outstretched wings, and consists of a hody^ greater and lesser wings, and pterygoid processes. It articulates with twelve bones, all those of the cranium, and five of the face ; posteriorly with the occipital and temporals, anteriorly with the ethmoid, palatals, frontal, and malars, laterally with the tem- porals, frontal, and parietals, inferiorly with the vomer and palatals, and sometimes with the superior maxillae. The body is hollowed into two cavities separated by the sphenoidal septum^ and opening anteriorly into the upper and back part of the nasal fossae behind the superior turbinate bone. The superior surface presents in front the ethmoidal spine, articulating with the cribriform plate of the ethmoid. On either side of this surface is a slight depression for the olfactory lobe, and its posterior margin is the limhus sphenoidalis. Behind this, on a lower plane, is the optic groove^ terminating on either side in the ojjtic foramen. Next is the olivary eminence [tidjerculum sellce), and next the pituitary fossa^ or sella Turcica (Turkish saddle): it is occasionally bounded in front by two middle clinoid processes ; behind is a square lamina, the dorsum sellce or dorsum ephippii (back of saddle), which slopes posteriorly down and back into the basilar groove : this slope is the clivus Blumenhachii (Blu- menbach's hill). The upper angles of this lamella project over the fossa as the posterior clinoid processes; the sides are grooved for the sixth pair of nerves. The sides of the body present a winding groove curved like the letter/ for the carotid artery in the cavernous sinus. Behind its commence- ment, at the lower lateral angle of the dorsum sellse, is the petro.ml pro- cess of the sphenoid, to fit against the apex of the petrous; opposite this, on the other side of the groove, is a tongue-like process, the lingida sphenoidalis. The posterior surface is quadrilateral, and united to the basilar process by cartilage in early life, and by bone after the fwenty-fifth year. 3 3 I 1:^ ^ ^ ^ t^ > ^ w PLATE IV. Fig. 1. — To face jxuje 44- Internnl pterygoid plate. JIamv.lar process.- Sphenoid Bone. Anterior Surface. Fig. 2. — To face page 47. ^u^ Eihmoiditi, Perpendicular Plate of Ethmoid (enlarged). Shown by removing the Right Lateral Mass. BOXES OF THE CRANIUM. 45 The anterior surface is marked in the middle Une by the sphenoidal crest^ which articulates with the perpendicular plate of the ethmoid. On each side of the crest is a mesial and lateral part : the lateral shows half-cells, to be completed by the ethmoid and orbital plate of the pala- tal ; the mesial part is smooth, and gives entrance anteriorly into the sphenoidal sinus, and forms part of the roof of the nose. The inferior surface presents the rostrum (beak), which continues the sphenoidal crest and fits between the alae of the vomer. The sphenoidal turbinate bones (spongy bones, conchse sphenoidales, bones of Berlin) form a considerable part of the anterior wall of the body of the sphenoid. They are curved and triangular, with apex backward. A small portion of them sometimes appears on the inner wall of the orbit between the ethmoid, frontal, sphenoid, and palate bones. Each lateral surface of the body is mostly occupied by the attachment of the greater wings, except in front a free surface bounds the sphenoidal fissure and forms the hindermost part of the inner wall of the orbit. The small or orbital wings (processes of Ingrassias) extend horizon- tally outward on a level with the fore part of the superior surface of the body : the extremity of each is pointed and comes almost into contact with the great wing. The inferior surface forms the upper boundary of the sphenoidal fissure and part of the roof of the orbit. The anterior border articulates with the orbital plate of the frontal ; the posterior is free, and forms the boundary between the anterior and middle fossae of the skull, and terminates internally in the anterior clinoid j^^^ocess. Be- tween this clinoid process and the olivary eminence is a semicircular notch in which the carotid groove ends. The optic foramen perforates the base of the wing, the parts above and below being called its roots. The great or temporal wings project out and up from the sides of the body : the back part of each is horizontal and fills the angle between the squamous and petrous portions of the temporal ; from its extremity pro- jects downward the spinous process. The fore part is vertical and three- sided, and lies between the cranial cavity, the orbit, and temporal fossa. The cerebral surface is concave, and forms part of the middle fossa of the skull. The external surface (temporo-zygomatic) is divided by the infratem- poral crest into a lower part looking down into the zygomatic fossa, and an upper part looking out into the temporal fossa. The anterior surface looks forward and inward, and consists of the orbital plate for the external wall of the orbit, and of a smaller portion above the pterygoid process which looks into the spheno-maxillary fossa and is perforated by the foramen rotundum. The 2^osferior border near the body bounds the foramen lacerum, and in its lateral part articulates with the petrous, forming a groove beneath for the cartilaginous portion of the Eustachian tube. The external bor- der, commencing at the spinous process, articulates with the squamous, and above it overlaps the anterior inferior angle of the parietal bone. 46 BONES OF THE HEAD. In front of this is a triangular surface formed by the upper margins of the cerebral, orbital, and temporal surfaces. The anterior margin artic- ulates above with the malar : below this is a free horizontal edge separat- ing the zygomatic from the spheno-maxillary surface. Above and inter- nally the orbital and cerebral surfaces meet at a sharp border which forms the inferior boundary of the sphenoidal fissure, and often shows a bony projection for the lower head of the external rectus. The pterygoid (wing-like) processes project downward and foi'ward, angle of 110° to 115°, from the junction of the body and great wings. Some consider them to rise from two roots, one representing a transverse process, one a rib, and the Vidian canal, the costo-transverse foramen. Each consists of two plates united in front and diverging behind, form- ing the pterygoid fossa for the origin of the internal pterygoid muscle. The external plate is broad and extends out and back, and gives origin by its outer surface to the external pterygoid muscle. The internal plate is long and narrow, and prolonged below into the hamular (hook-like) process, round which plays the tendon of the tensor palati muscle. The upper part of the inner plate turns in beneath the body, and remains distinct as a slightly raised edge, the vaginal process, which meets the everted margin of the vomer. At the angle of the vaginal process with the internal plate is a groove which, with the sphenoidal process of the palate, forms the ptery go-palatine canal. Posteriorly, at the base of the inner plate, is the pterygoid tubercle, to the inner side of and below the Vidian canal : between this and the pterygoid fossa is the scaphoid fossa for the origin of the tensor palati muscle. Lower down, on the posterior margin of the plate, is the processus tuharius, which supports the cartilage of the Eustachian tube. Between the lower ends of the plates is the pterygoid notch, occupied by the pyramidal process of the palate bone. Name the fissures and foramina of the sphenoid. Each half i)resents a fissure, four foramina, and a canal. The sjphe- noidal fissure is the oblique interval between the great and small wings, closed externally by the frontal bone. ^ It opens into the orbit and trans- mits the third, fourth, ophthalmic division of the fifth, and the sixth cra- nial nerves, some sympathetic filaments from the cavernous plexus, the orbital branch of the middle meningeal artery, recurrent branch of the lachrymal artery, and the ophthalmic vein. Above and to the inside of this fissure is the optic foramen, piercing the base of the small wing and transmitting the optic nerve and ophthalmic artery. The foramen rotundum pierces the great wing below the sphenoidal fissure and trans- mits the superior maxillary nerve. Behind and external to this is the foramen ovale, near the posterior margin of the great wing, sometimes incomplete : it transmits the inferior maxillary nerve, the small menin- geal artery, and sometimes the small superficial petrosal nerve. The foramen spinosum pierces the great wing near the posterior angle, and transmits the middle meningeal artery and n. spinosus, a recurrent branch BONES OF THE CRANIUM. 47 of the Infraniaxillaiy. From the foramen spinosum projects backward a thin horizontal sphoio-pefrosal lamina, which reaches the upper border of the Eustachian canal on the petrous. The Vidian canal pierces the base of the internal pterygoid plate antero-posteriorly ; it passes from the foramen lacerum to the spheno- maxillary fossa, transmitting the Vidian nerve and vessels. A spicule of bone may connect the middle clinoid process (when present) with the anterior, forming a carotico-dinoid foramen for the carotid artery. Interclinoid ligaments are normally present beneath the dura. The outer pterygoid plate may be connected by bone or ligament with the spinous process. The foramen of Vesalius for an emissary vein is sometimes present on the inner side of the foramen ovale. The canalicuhis imiomimatus is some- times present for the small superficial petrosal nerve internal to the foramen spinosum. Describe the ethmoid bone. The ethmoid (sieve-like) projects down between the orbital plates of the frontal, and enters into the formation of the cranium, orbits, and nasal fossoe. It consists of thin plates enclosing irregular cells — a ver- tical plate and two lateral masses united above by the horizontal cribri- form plate, It^ articulates with thirteen bones — fifteen including the sphenoidal turbinate — the frontal, sphenoid, and vomer, the nasals, lachrymals, superior maxillae, palatals, and inferior turbinate bones. The vertical X)late forms the upper third of the nasal septum, and presents grooves and canals^ for olfactory nerves. Its superior border appears in the cranial cavity as the crista galli (cock's comb) ; posteriorly this process is thin, and anteriorly is broadened into two alar processes, between which is usually a groove completing the foramen caecum with the frontal. If the vertical plate be deflected below the cribriform, the crista galU is inclined in the opposite direction. The anterior border of the plate articulates with the nasal spine of the frontal and with the nasal bones ; the inferior border in front with the triangular cartilage of the nose, and behind with the vomer; the posterior margin with the sphenoidal crest. Each lateral mass or labyrinth encloses three sets of spaces — the anterior, middle, and posterior ethmoidal cells : they do not communi- cate with each other. Externally is the paper-like orbital plate, or os planum (lamina papyracea), closing in the middle and posterior cells: it articulates in front with the lachrymal, behind with the sphenoid, above with the frontal, and below with the superior maxilla and palate bones. On this aspect below the plate is a groove belonging to the middle meatus of the nose : it turns up anteriorly, and is continued by the infundibuhim through the anterior ethmoidal cells to the frontal sinus; the middle cells open into the horizontal part of the groove. The lateral mass in front of the orbital plate is covered in by the lachry mal : from this part the uncinate process curves back, down, and out, 48 BONES OF THE HEAD. helping to close the orifice of the antrum : it articulates below with the ethmoidal process of the inferior turbinate. The inner aspect of each lateral mass is in the outer wall of the nasal fossa. Above is a channel, the superior meatus^ passing from behind to about the middle of the bone : it communicates with the posterior cells. The plate overhanging it is the superior turbinate process or superior spongy hone (concha sup. ) ; the space above that is in the roof of the nose. Below the groove is the inferior turhinafe process of the ethmoid or middle spongy ione (concha inf ), rolling convexly toward the nasal fossa : it forms the lower border of the lateral mass. Two grooves cross the upper margin of the lateral mass, forming with the frontal the two internal orbital canals. Posteriorly the mass is ankylosed with the sphenoidal spongy bone. The cribriform plate occupies the ethmoidal notch of the frontal. It presents the olfactory groove on each side of the crista galli and foramina for the olfactory nerves ; the foramina of the middle set are few and are simple perforations; in the external and internal sets they are more numerous, and are orifices of small canals which subdivide on the vertical plate and lateral mass. Anteriorly is a fissure close to the base of the crista galli, and external to it a notch connecting with the anterior in- ternal orbital canal for the passage of the nasal nerve and anterior eth- moidal artery from the orbit to the cranium, and thence to the nasal fossa. BONES OP THE FACE. Describe the superior maxillary bone. The superior maxilla is the principal bone of the face, supporting the upper teeth of one side, helping to form the hard palate, floor of orbit, floor and outer wall of nasal fossa. There are a body and four processes for description. The body is a hollow half-cylinder, presenting an ex- ternal surface subdivided into an anterior and posterior, an internal and superior ; the processes are nasal, alveolar, malar, and palatal. The body encloses the antrum of Highmore, which opens into the middle meatus of the nose. The superior maxilla articulates with nine or ten bones — with its fellow, with the nasal, frontal, lachrymal, ethmoid, palate, malar, vomer, inferior turbinate, and sometimes with the sphe- noid at the outer extremity of the spheno-maxillary fissure. The anterior or facial surface is marked below by eminences corresponding to fangs of the teeth. Internal to the eminence for the canine is the incisor or wyrtifonn fossa; external to it is the diQQ\)QV canine fossa ; above the latter, below the margin of the orbit, is the infraorbital foramen. The inner margin of this surface is cut by the nasal notcJi^ the sharp edge of which is prolonged into the anterior nasal sjyine. The posterior or zygomatic surface looks into the zygomatic and spheno- maxillary fossae : it presents two or more apertures of the posterior den- tal canals ; below and posteriorly is a rough tuberosity. At the junction N BONES OF THE FACE. 49 of this surface with the nasal and orbital is a small triangular space on which the orbital process of the palate rests, the palatine trigone (Henle). The internal or yta^al surface presents in front the inferior turbinate crest ; below it is the smooth concavity of the inferior meatus ; above it a small surface forming the atritim (entry) of the middle meatus. Be- hind tlie nasal process is the lachrymal groove, i inch long, inclined down and out, opening into the inferior meatus ; the groove is converted into the canal of the nasal duct by the lachrymal and inferior turbinate. Behind it is the opening of the antrum ; above this are small half-cells belonging to the middle ethmoidal set. Behind the opening of the an- trum the surface is rough for articulation with the palate bone, and trav- ersed by a groove running down and forward, forming with the palate the posterior palatine canal. The orbital surface is triangular and flat ; externally is a rough surface for the malar ; internally is first the lachrymal notch, and behind it a pretty straight margin for the ethmoid and orbital process of the palate. The postero-external border is free and bounds the spheno-maxillary fis- sure. The infraorbital groove commences well back on this surface, lead- ing to a canal of the same name which opens anteriorly at the infraorbital foramen : from the canal are given off the anterior and middle dental canals in the substance of the bone. The nasal process projects up, in, and back ; its external surface is smooth ; the hinder part of the mner surface completes the anterior eth- moidal cells ; below this the surface is crossed by the superior turbinate crest (agger nasi) for the inferior turbinate process of the ethmoid (mid- dle spongy bone). The anterior border articulates ivith the nasal bones and above with the frontal ; posteriorly is a continuation of the lachrymal groove, bounded internally by a sharp edge articulating with the lachry- mal, and externally by a smooth border : where this border joins the orbital surface is the lachrymcd tubercle. Tlie alveolar process is thick and hollowed into eight alveoli. The malar process is triangular, continuous in front and behind with the facial and zygomatic surfaces of the body. Superiorly it is rough for the malar : the inferior border forms a thick buttress opposite the first molar. The palate process with its opposite forms three-fourths of the hard palate. ^ Above it is concave transversely, and forms part of the floor of the inferior meatus. Below it is arched, and shows lateral grooves for nerves and vessels : its posterior extremity falls short of that of the alveolar arch and the space is filled by the palate bone. The inner border rises into a nasal crest which receives the vomer ; in front a more elevated part is the incisor crest, prolonged into the anterior nasal spine. By the side of the incisor crest is a foramen, becoming a groove : when the bones are united there is one orifice below, with right and left branches above, called the incisor foramina or foramina of Stenson, for the transmission of arteries (Fig. 3). The lower aperture is the anterior palatine fossa ; in the middle line, opening into it, are the foramina of 4 —A. 50 BONES OF THE HEAD. Scarpa^ the left naso-palatine nerve passing through the anterior one and the right through the posterior. From the anterior palatine fossa are seen two sutures passing to the interval between the canine and lat- FiG. 3. \ Ccmeil 2f Sl^rtsorv^ of Scarpa^ Ihslr^jpuZcaine CctnaZ/ Accessortf palaJtrrc^ The Palate and Alveolar Arch. eral incisor tooth ; the sutures are to be seen in the inferior meatus. They mark oif the intermaxillary hone^^ and include the whole thickness of the alveolar processes, the nasal spine, and sockets for incisor teeth. No trace of the suture is seen on the racial surface, as an outgrowth, the incisor process, forms the front wall of the incisor sockets. The maxillary sinus, or antrum, is irregularly pyramidal ; the base is at the nasal surface of the body and the apex extends into the malar process. Its aperture is closed in part by the uncinate process of the ethmoid, the ethmoidal process of the inferior turbinate, and the maxil- PLATE V. Fig. I.— To face page 61. Orbital process. Orbital surface. Maxillary surface. Superior meatus. Spheno-palaline foramen^^ Maxillary process. Horizontal Plate, Left Palate Bone, internal view (enlarged). Fiu. 2. — To face page 51. Orbital process. Sphenoidal palatine foramen. Sphenoidal process. Articular portion. Is on-articular portion. External Surface, ''^*% Horizontal Plate, Posterior nasal spine. Left Palate Bone, posterior view (enlarged). PLATE VI. Fig. 1. — To face page 52. With sup. maxill. hones and palate. Vomer. Fig. 2. — To face page 54- ^''m Kight Inferior Turbinated Bone, internal surface. Fig. 3. — To face page 54- Bight Inferior Turbinated Bone, outer surface. BONES OF THE FACE. 51 lary process of the palate behind ; the lachrymal in front rarely assists. The alveolus of the first molar is most prominent in the floor. Describe the palate bone. This bone is L-shaped, and forms the back part of the hard palate and the lateral wall of the nose between the superior maxilla and internal pterygoid plate. It presents a horizontal, a vertical plate, and three processes. It articulates with six bones — its fellow, the superior maxilla, the ethmoid, sphenoid, vomer, and inferior turbinate. The horizontal or palate plate is concave above in the nasal fossa ; near its posterior border is a transverse ridge for the tensor palati muscle. The posterior border is free and concave, gives attachment to the soft palate, and is prolonged internally into the posterior nasal or palatine spine^ which continues the nasal crest of the superior maxillae supporting the vomer. It is grooved externally by the p)osterior palatine canal. The vertical plate is thin ; its nasal surface is divided into two parts by the inferior turbinate crest for the inferior turbinate bone ; the middle meatus is above it and the inferior below. At the upper part is the superior turbinate crest for the middle spongy bone, and above this a groove in the superior meatus. The external surface presents above and behind a smooth surface, forming the inner wall of the pterygo-maxillary fissure, and leads to the posterior palatine r/roove. In front of the groove the surface is applied to the superior maxilla and sends the maxillary pro- cess forward. Behind the groove the surface articulates below with the maxilla and above with the pterygoid process. The pyramidal process or tuberosity juts out behind and fits in between the pterygoid plates : it presents posteriorly a smooth middle district en- tering into the pterygoid fossa ; internal to it is a groove for the internal pterygoid plate, and externally a rough area for the external plate. Fart of the tuberosity appears in the zygomatic fossa. Inferiorly, close to the horizontal plate, are the posterior and external accessory palatine canals. The orbital process rests on the anterior margin of the vertical plate : it has five surfaces, three articular, and two, the superior and external, are free. The superior surface forms the posterior angle of the floor of the orbit ; the external looks into the sphenomaxillary fossa ; the anterior articulates with the maxilla, the internal with the ethmoid, and the pos- terior with the sphenoid. The process is usually hollow, and completes a posterior ethmoidal cell or may open into the sphenoidal sinus. The sphenoidal process curves up and in irom the posterior part of the vertical plate ; it has three surfaces : the superior is in contact with the under surface of the body of the sphenoid, and is grooved for the ptery go-palatine canal; the internal surface looks into the nasal fossa and touches the ala of the vomer ; the external looks into the spheno- maxillary fossa. 52 BONES OF THE HEAD. The spheno-palathie notch is between these two processes, converted by the body of the sphenoid into a foramen of the same name. The posterior palatine canal may be wholly confined to the palate bone. The spheno-palatine notch may be converted to a foramen by union of the sphenoidal and orbital processes. The orbital process may be enlarged by a separate ossification from the ethmoid or sphenoid. Describe the vomer. The vomer (ploughshare) is thin and quadrilateral, and placed verti- cally between the nasal fossae. The upper and posterior borders, the anterior and inferior, are of nearly equal lengths. It articulates with six bones — the sphenoid, ethmoid, two palate, two superior maxillary — and with the septal cartilage of the nose. Each surface presents a groove leading the naso-palatine nerve to the foramen of Scarpa. The superior border divides into two alae, which receive the rostrum of the vomer between them ; each ala meets the vaginal process of the sphenoid and the sphenoidal process of the palate. There are usually three vomero-basilar canals — a median, between ala and rostrum for nutrient vessels ; an upper lateral one, between the body of sphenoid and root of vaginal process, carrying vessels to the sphenoidal cells ; a lower lateral one, between the body of sphenoid and sphenoidal process of palate, carrying vessels and nerves from the nasal and spheno-maxillary fos- sae to the upper pharynx. The anterior border is grooved in its lower half for the septal cartilage ; in its upper half it is ankylosed on one or both sides, usually the right, with the perpendicular plate of the ethmoid. At the inferior anterior angle is a short vertical edge to fit in behind the incisor crest of the maxillae : from its upper end a process runs forward in the groove of the crest, and from its lower end a point may project down between the incisor foramina. The inferior border articulates with the nasal crest of the maxillae and palate bones : the posterior border is thin and free and separates the posterior narcs. Describe the malar bone. This cheek-bone separates the orbit from the temporal fossa and ar- ticulates with four bones — the frontal, sphenoid, temporal, and superior maxillary. It is quadrangular, with the angles directed vertically and horizontally : it may be thought of as formed of a triangular orbital plate united at a sharp angle to a quadrangular malar plate. The outer sur- face presents a little below the centre the malar tuberosity^ and above this the orifice of the malar canal. The inner surface is concave, looks into the temporal and zygomatic fossae, and presents a roughness for ar- ticulation with the superior maxilla. The upper angle or frontal process is serrated for the external angular process of the frontal. The temporal border behind this is sinuous and continuous with the upper border of the zygoma. BONES OF THE FACE. 53 The posterior angle or tenmoral process has the zygoma resting upon and articulating with it. The postero-inferior border, the masseteric^ completes the lower edge of the zygomatic arch ; the antero-inferior . border, maxillarij^ and a rough part of the inner surface, articulate with the malar process of the superior maxilla. The orbital border is exca- vated, and forms a great part of the orbital margin, ending internally just above or inside the infraorbital foramen. From this the orbital process projects back, forming the fore part of the outer wall of the orbit, articulating with the great wing of the sphenoid. On the orbital surface are the openings of two canals — the temporal opening on the temporal surface, and the malar opening on the facial : they transmit the tem- poro-malar branches of the superior maxillary nerve. A horizontal suture may divide the bone into two unequal parts. The canals may have a common opening on the orbital surface. There may be a marginal process at the upper part of the temporal border (more often on the right side) for attachment of a band of temporal fascia. The anterior ex- tremity of the spheno-maxillary fissure may be completed in one of three ways: by the malar in more than half the cases, by the articulation of the sphenoid with the superior maxilla, or by a Wormian bone. The antrum of Highmore may extend into the malar. Describe the nasal bones. The two form the bridge of the nose, and each articulates with four bones — the frontal, superior maxillary, ethmoid, and its fellow. They are narrow and thick above, broader and thinner below. They articulate above with the inner part of the nasal notch of the frontal. The inferior border is free, and gives attachment to the lateral nasal cartilage : it usually has a small notch near the inner end. The ex- ternal border is longest, and articulates by means of small teeth with the nasal process of the superior maxilla. The internal border meets its fellow in a somewhat irregular internasal suture, which commonly deviates to one side at the upper end. Pos- teriorly the two form a crest which rests from above down on the nasal process of the frontal, the vertical plate of the ethmoid, and the septal nasal cartilage. The facial surface is convex below and concave above, and presents vascular foramina. The posterior surface is concave, and a little external to its centre is a longitudinal groove for the nasal nerve. These bones are relatively large in white races, small and flat in the black and yellow races. The internasal suture is obliterated in apes. There may be small internasal bones at the lower extremity of the internasal suture. Describe the lachrymal bone. The lachrymal, or os unguis^ is a thin scale like a finger-nail at the an- terior and inner part of the orbit. It articulates with four bones — frontal, ethmoid, superior maxilla, and inferior turbinate. Its external surface is divided by a vertical ridge, the lachrymal crest : in front of it 54 BONES OF THE HEAD. is the lachrymal groove, and this part is prolonged below as the descend- ing proce^H to articulate with the inferior turbinate ; behind the crest the surmce is smooth and forms part of the orbit, and it is produced below into the hamular process^ which comes forward in the lachrymal notch of the superior maxilla and bounds the outer side of the orifice of the nasal duct. The internal surface is a depressed furrow completing above some of the anterior ethmoidal cells, and below it looks into the middle nasal meatus. This bone may be absent, perforated, or divided into pieces ; the hamular process may be wanting, small, or so long as to extend upon the face, A separate ossicle may take its place, the lesser lachrymal bone. Describe the inferior turbinate bone. The inferior turbinate or spongy bone projects like a shell into the nasal cavity, separating the middle from the inferior meatus. Its con- vexity looks in and its lower margin is rolled on itself Its attached margin articulates in front with the inferior turbinate crest of the supe- rior maxilla, and then ascends abruptly as the lachrymal process to com- plete the lachrymal canal. Behind this, and nearer the back than the the front, the bone is folded down as the maxillary process^ looking over the aperture of the antrum, and forming part of its inner wall : on the upper border of this process is the ethmoidal process, which articu- lates with the uncinate of the ethmoid. Posteriorly, the bone is attached to the inferior turbinate crest of the palate : the posterior extremity is elongated and pointed, the anterior flat and broad. The bone articulates with the superior maxilla, lachrymal, ethmoid, and palate. No muscle is attached to it. The negro may have four tur- binate bones. Describe the inferior maxillary bone. The lower jaw, or mandible, is the strongest bone of the face, and articulates with the glenoid fossae of the temporals. It consists of a curved horizontal portion or body and two ascending branches or rami. The body shows in front a faint vertical ridge, the symphysis of two originally distinct pieces : this expands into the mental protuberance, which becomes prominent on each side inferiorly as the mental tubercles. The superior or alveolar border is hollowed out into sockets for teeth. The inferior border, or base, is thick and rounded, and projects beyond the superior. Below the incisor teeth is the mc/so?-/os.9a; more exter- nally is the mental foramen midway between the upper and lower bor- ders, under the interval between the two bicuspids : it is the anterior opening of the dental canal. Below the foramen the external oblique line runs up and back from the mental tubercle to the anterior margin of the ramus. The deqp surface of the body presents inferiorly near the symphysis an oval fossa for the attachment of the digastric muscle: above it are the mental spines, the lower being a median ridge for the genio-hyoid muscles, and the upper a pair oi tubercles for the genio- THE SKULL AS A M^HOLE. 55 hyoglossi : there may be four tubercles ( 1 1 ) or two ( • • ) or a vertical ridge (I) or one prominence ( • ). Above them a small foramen pene- trates the bone and above this a narrow median groove marks the sym- physis. Below the mental spines, and passing up and back to the ramus, is the internal oblique line or mylo-hyoid ridge^ for the mylo-hyoid muscle and a slip of the superior constrictor of the pharynx. Above this line is a fossa for the sublingual gland, and below it another for the submax- illary. The ramus is thinner than the body, and where its posterior border meets the base it forms the slightly everted angle. The external surface is flat, and near the angle it shows oblique lines for tendinous attach- ment of the masseter muscle. At the centre of the internal surface^ on a level with the crowns of the molar teeth, is the inferior dental foramen^ leading to the dental canal: the inner margin of the foramen is sharp anteriorly, and called the lingula mandihidce. Beginning at the notch behind the hngula is the mylo-hyoid groove (sometimes a canal), termi- nating below the hinder end of the mylo-hyoid ridge. Behind this is a roughness for the internal pterygoid muscle. On the upper border of the ramus are two processes — the condyle for articulation and the coro- noid for muscular attachment : they are separated by the semilunar or sigmoid notch. The condyle passes up from the posterior part of the ramus, supported on a constricted neck^ on the front of which internally is a depression for the external pter3^goid muscle. One-third inch (8 mm. ) be- low the articular surface there may be an external tubercle for the external lateral ligament. The condyle is convex, transversely elongated, and the axes of the two would meet at the anterior margin of the foramen mag- num. The coronoid process passes up from the fore part of the ramus, in- clined out and somewhat beak-shaped : by its apex, sharp margins, and inner surface it gives attachment to the temporal muscle. The anterior border of the ramus shows three oblique ridges — an ex- ternal one to the end of the external oblique line ; internal to that is a groove bounded posteriorly by a ridge passing from the internal oblique line to the middle aspect of the coronoid; at the lower part of the groove, extending a short distance to the outer side of the alveolus, is the third or buccal line. The lower jaw consists of a thick shell of compact tissue enclosing cancel- lous tissue ; the dental canal in its posterior two-thirds lies close to the inner compact layer ; it is prolonged beyond the mental foramen under the canine and incisor teeth. There may be two dental canals. The angle of the jaw in the adult is about 120°, infancy 140° or more ; in old and toothless jaws it is increased. These changes are due to development, absorption of alveolar arch, and strength of masseter muscles. THE SKULL AS A WHOLE. Describe the sutures. The skull-bones are closely fitted by uneven edges, there being inter- 56 BONES OF THE HEAD. posed a little fibrous tissue continuous with the periosteum ; the den- tations are confined to the external table, the edges of the inner table lying only in apposition. The lower jaw has a movable articulation, diiFering from the others. The sutures around the parietal bones have special names : between the two is the sagittal^ behind them the lamh- doid, in front of them the coronal. All the sutures may be arranged in three groups — a median longi- tmiinal, a lateral longitudinal, and a vertical transverse. The first con- sists of the sagittal, and in the infant the frontal ; the second begins in the median line in front, and includes on each side the fronto-nasal, fronto-maxillary, fronto-lachrymal, fronto-ethmoidal, fronto-malar, fronto- sphenoidal, spheno-parietal, squamo-parietal, and masto-parietal ; the third^ comprises the coronal and spheno-squamous, the lambdoid and occipito-mastoid, and also the transverse sutures at. the base of the skull. Sometimes the great wing of the sphenoid, the parietal, the squama, and the frontal bones do not meet, and the short spheno-parietal suture is not formed ; the frontal and squama unite in a vertical fronto-temporal suture continuing the coronal: this is the rule in the gorilla and chimpanzee. In this situation is often developed the epipteric bone. After about thirty years of age many sutures close, union taking place on the inner surface first : the parts to close first are the sagittal suture between the parietal foramina and the lower ends of the coronal suture. THE WORMIAN BONES. These, ossa triquetra, ossa suturarum, are irregular ossifications between cranial bones rarely found in the face. They are usually symmetrical, and are most common in the lambdoid suture, occupying the place of the superior angle of the occipital bone ; may be at either anterior angle of the parietals. They usually include only one plate of the skull. The ossiculum jugular e may be found at the jugular foramen. EXTERNAL SURFACE OP THE SKULL. The external surface may be divided into superior, inferior, anterior, and lateral regions. Describe the superior region. This extends from the supraorbital margins to the superior curved line of the occiput, bounded laterally by the temporal lines. It is a smooth, convex surface covered by muscle and aponeurosis. The great- est transverse diameter of the skull is at the junction of the posterior and middle thirds — viz. 5f inches (140 mm.) ; the greatest longitudinal diameter from the under margin of frontal bone to the external occi- pital protuberance is 6* inches (170 mm. ). As the head is usually held it makes an angle of 20° with the horizon. Describe the anterior region. This region presents the openings of the orbits, the bridge of the nose, EXTERNAL SURFACE OF THE SKULL. 57 below tliat the anteinor nasal aperture {apertura pyriformis), presenting the anterior nasal spine below. Below the aperture are the incisor fossae of the upper jaw, below the orbits the canine fossae, and external to them the malar prominences. The lower jaw completes the skeleton of the face with its incisor fossae, mental prominence, etc. In a nearly vertical line on either side are three foramina for the exit of some part of the three divisions of the fifth cranial nerve — viz. the supraorbital, infraorbital, and mpntal. There are also the malar for- amina on the malar bone. The nose is rarely placed in the centre of the face, and the nasal aper- ture is often unsymmetrical, a deflection of the septum occurring toward the wider half Describe the orbits. The orbits are pyramidal fossae, somewhat quadrilateral, with their bases turned out and forward : their inner walls are nearly parallel, and their outer walls diverge at nearly right angles to each other. Each is formed of seven bones, or eleven for the two — the frontal, sphenoid, malar, superior maxillary, lachrymal, ethmoid, and palate. The roof of each is formed by the orbital plate of the frontal and small wing of the sphenoid; the floor by the malar, superior maxilla, and orbital plate of the palate; the inner wall by the nasal process of the superior maxilla, the lachrymal, ethmoid, and body of the sphenoid ; the outer wall by the malar and great wing of the sphenoid. The sphenoidal fissure at its inner part occupies the apex of the orbit; its outer ex- tremity lies between the roof and outer wall. The optic foramen is internal to and above the fissure. In the angle between the external wall and floor is the spheiio-maxillary fissure^ bounded by the palate, superior maxilla, malar, and sphenoid bones: it leads into the spheno-maxillary fossa at its back part and zygomatic fossa at its fore part. Passing^ forward from the margin of this fissure is the commencement of the infraorbital canal. On the inner wall in front is the lachrymal groove, leading to the canal of the nasal duct, and farther back, between the frontal and ethmoid, are the anterior and posterior internal orbital canals. At the inner margin of the roof is the supraorbital foramen or notch. Within the external angular process is the lachrymal fossa^ and on the outer wall are the temporal and malar canals. Describe the lateral region of the skull. This presents from behind forward the mastoid portion, the mastoid foramen, the external auditory meatus, the glenoid fossa with condyle of lower jaw, eminentia articularis, coronoid process, and zygomatic arch. Above this arch is the temporal fossa, and below it, separated by the infratemporal crest, is the zygomatic fossa. The temporal fossa, occupied by the temporal muscle, is bounded above by the temporal crest of the frontal and the lower temporal line 68 BONES OF THE HEAD. of the parietal : the latter runs into the supramastoid crest, and that into the zygomatic arch. The zygomatic or wfratemj^oral fossa contains a part of the temporal muscle, the external and internal pterygoids, the internal maxillary artery, and the inferior maxillary nerve. Some of its boundaries are indefinite : externally is the ramus of the lower jaw ; superiorly the great wing of the sphenoid, showing the foramen ovale and spinosum, also a small part of the squamous portion of the temporal ; anteriorly is the lower part of the malar and zygomatic surface of the superior maxilla ; the inferior limit is the extremity of the external pterygoid plate and alveolar border of the superior maxilla. The inner wall is formed by the external ptery- goid plate ; the posterior limit is the eminentia articularis and posterior border of the pterygoid plate. Inferiorly the pterygoid process approaches close to the superior maxilla, but is prevented from meeting by the pyramidal process of the palate. Above they are separated by the pterygo-maxUlan/ fissure^ leading into the spheno-maxiUanj fossa. Running at right angles to the fissure is the spheno-m axillary fissure opening into the orbit. Describe the spheno-maxillary fossa. This is a small triangular space at the angle of junction of the above- named fissures, placed beneath the apex of the orbit. It is bounded above by the body of the sphenoid, in front by the superior maxilla, behind by the base of the pterygoid, and internally by the vertical plate of the palate. It has three fissures terminating in it — the sphenoidal, spheno-maxillary and pterygo-maxillary. It communicates with four fossae — the orbital, nasal, zygomatic, and middle fossa of the base of the skull ; and has opening into it five foramina — three from behind, the foramen rotundum, the Vidian, and the pterygo-palatine canals; internally is the spheno-palatine foramen, and inferiorly the posterior palatine canals, and occasionally the accessory posterior palatine canals. Describe the external base of the skull. ("Base of skull" properly means base of the cranium, and does not include the facial bones ; we have followed, however, the usual descrip- tion, and include the inferior maxilla.) It is divisible into three parts — anterior, middle, and posterior. The anterior division consists of the palate, alveolar arches, and body of the inferior maxilla. It is traversed longitudinally by a median suture, and transversely by that between the maxillary and palate bones. In front is the anterior palatine fossa^ with the four foramina opening into it ; farther back are the under surface of the tuberosity of the palate, the apertures of the posterior and external palatine canals, and the posterior nasal spine. The middle division extends back to the foramen magnum, and is called the guttural fossa (relating to the throat). In the mid-line is the basilar process, and in front of that the body of the sphenoid covered EXTERNAL SURFACE OF THE SKULL. 59 by the alae of the vomer. On each side the petrous portion reaches to the extremity of the basilar process, and between the petrous and squamous is the back part of the great wing of the sphenoid. In front are the posterior nares or choance (funnels), separated by the vomer, bounded above by the sphenoid, below by the horizontal plates of the palate bones, and laterally by the internal pterygoid plates. On each side are the ptery go- palatine and Vidian canals, the scaphoid and ptery- goid fossae. A line froul the external pterygoid plate to the spine of the sphenoid separates this surface from the zygomatic fossa : internal to this line is the groove for the cartilaginous part of the Eustachian tube. Between the apex of the petrous, the basilar process, and the sphenoid is the foramen lacerum. (This is the only foramen properly called "lacerated.") This with the petro-basilar fissure is filled with fibrous tissue, and may contain Wormian bones. Passing back and out from this is the petro-sphenoidal fissure, the styloid and vaginal processes, and the stylo-mastoid foramen ; more internally are the anterior condylar foramina and the jugular fossa. This fossa, is divided into three com- partments by processes of dura mater. The inferior petrosal sinus is in the anterior one, the lateral sinus, some ascending pharyngeal and occi- pital arteries in the posterior one, and the ninth, tenth, and eleventh cranial nerves in the middle one. Other points have been described with the temporal bone. The posterior division presents on either side of the foramen magnum the occipital condyle, jugular process, occipital sulcus, digastric fossa, and mastoid process. Behind the foramen magnum is the tabular part of the occipital up to the superior curved line. Into this posterior divis- ion are inserted all the muscles running up to the skull from the ribs, spines, and transverse processes. Henle describes for base of skull the base of the cranial bones : the foramen magnum is where the vertebral canal broadens out into the cranium ; behind it is the part corresponding to the vertebral arches, in front the part corre- sponding to the vertebral body. The line of separation passes through the mastoid and jugular processes, the condyles, and the foramen magnum. In front of this line are two other regions : the " middle girdle " nearly corre- sponds to the middle fossa of the interior ; its anterior border goes on either side from the pharyngeal spine, in front of the pterygoid process to the outer extremity of the crista orbitalis, which is the upper border of the spheno- maxillary fissure. The anterior portion in front of the pharyngeal spine forms the roof of the "vegetative tube." Describe the interior of the cranium. The inner table presents impressions for cerebral convolutions. The thickness of the skull-cap, or calvaria, is J to } inch. The base of the skull varies in thickness, thinnest at the cribriform and orbital plates, where there is no diploe ; also thin in the inferior occipital fossa, in the squama, and glenoid fossa. The inner surface of the calvaria is dome- like, formed by the frontal, parietal, and occipital bones. It is marked 60 BONES OF THK HEAD. by the superior longitudinal sulcus, small meningeal grooves, and Pac- chionian fossae. The only apertures are the inconstant parietal foramina. Describe the internal base of the skull. This surface is divided into three fossae — anterior, middle, and poste- rior. The anterior fossa is formed by the orbital plates of the frontal, the cribriform of the ethmoid, the small wings and. part of the body of the sphenoid : it supports the frontal lobes of the cerebrum. It is convex laterally, with a hollow over the cribriform plate, where the crista galU stands up separating the olfactory grooves. There is here the foramen caecum, the olfactory foramina, openings of the internal orbital canals, and the foramen for the nasal nerve. The middle fossa is on a lower level than the anterior, and consists of a median and two lateral parts. The median part is narrow, presenting the olivary eminence, the sella Turcica, and limited behind by the dor- sum sellae. Laterally is the great wing of the sphenoid, the squama, and antero-internal surface of the petrous portion. This lodges the tem- poral lobe of the cerebrum. The foramina present are the optic, sphe- noidal fissure, foramen rotundum, ovale, spinosum, lacerum, and hiatus Fallopii. The posterior fossa is deeper and larger than the others, and lodges the cerebellum, medulla, and pons. The occipital bone, the petrous and mastoid portions, postero-inferior angle of the parietal, and body of the sphenoid enter into it. In the centre is the foramen magnum, and on each side, in a nearly vertical line, are the anterior condylar foramen, jugular foramen, and internal auditory meatus. Behind the jugular foramen is the posterior condylar (if present), and higher up the mas- toid foramen, both opening into the lateral sulcus. By the internal auditory meatus the facial and auditory nerves, the portio intermedia, and the auditory vessels leave the cranium. What grooves are there for blood-vessels ? That for the middle meningeal artery commences at the foramen spinosum, and passes anteriorly to the great wing of the sphenoid, and posteriorly upon the squama and parietal. There is also the groove for tlie internal carotid artery on the side of the body of the sphenoid, the groove for the superior longitudinal sinus terminating at the internal occipital protuberance, those for the lateral sinuses, and others for the superior and inferior petrosal sinuses on the petrous portion. Describe the nasal cavities and communicating air-sinuses. The 7iasal fossce. are placed one on each side of a median vertical sep- tum. They open in front by the anterior nasal aperture and behind by the posterior nares. They communicate with the sinuses of the frontal, ethmoid, sphenoid, and superior maxillary bones. They are narrow transversely, especially above. The internal icall, or septum nasij is INTERNA li SURFACE OF THE SKULL. 61 formed by the perpendicular plate of the ethmoid, the vomer, nasal spine of the frontal, crests of the nasal, rostrum of sphenoid, crests of the maxillary, and palate bones. There is an angular deficiency in front, filled by the septal cartilage, which usually deviates to one side. The roof is horizontal in the middle part and sloping in front and be- hind. The middle part is formed by the cribriform, the fore part by the nasal and frontal bones, the back part by the body of the sphenoid, the ala of the vomer, and sphenoidal process of the palate. In the angle formed by the cribriform and body of the sphenoid is the siiheno-eth- moidal recess : the sphenoidal sinus opens upon its posterior wall. 11\Q floor is formed by the palate processes of the maxillary and palate bones; it is smooth and concave transversely, and shows the orifice of the incisor foramen. The external wall is formed by the nasal, superior maxillary, lachrymal, ethmoid, inferior turbinate, palate, and internal pterygoid plate. The superior and inferior turbinate processes of the ethmoid and the inferior spongy bone overhang the three meatuses. The superior meatus is very short, and placed be- tween the superior and inferior turbinate processes; into it open in front the posterior ethmoidal cells, and behind the spheno-palatine foramen.^ The middle meatus is above the inferior spongy bone, and communicates with the anterior and middle ethmoidal cells, with the maxillary sinus, and in front by the infundibulum with the frontal sinus. The inferior meatus^ longer than the others, lies between the inferior spongy bone and the floor of the cavity ; in front is the orifice of the nasal duct. The Air- Sinuses. These communicate with the nasal cavities by narrow orifices : with the exception of the maxillary sinus (antrum) they are not present at birth. In old age they increase in size by absorption of neighboring cancellated tissue. The antrum begins to be formed about the fourth month. The frontal, ethmoidal, and sphenoidal excavate their respective bones in childhood, and at puberty undergo a great enlargement. Their purpose may be for resonance. They have been sufiUciently described with the different bones. OSSIFICATION OF THE BONES OF THE HEAD. Ossiiacatioas at the base of the cranium take place for the most part in car- tilage ; those of the roof of the skull and of the face originate in membrane, excepting the inferior turbinate and part of the lower jaw. The diploe and air-sinuses are absent at first. The ocdpHal bone consists of four pieces at birth — a basilar, tabular, and two condylar parts. Tlie basilar and condylar parts have each one nucleus ; in the tabular part there are usually four, the upper pair deposited in membrane and representing the interparietal bone of animals. This subdivision may exist in the human skull. The parietal hone begins to ossify in membrane at the seventh week : it has 62 BONES OF THE HEAD. two centres, which speedily unite into one mass at the position of the future parietal eminence. The radiating ossification leaves a notch in front of the upper posterior angle, giving rise when united to its fellow to the sagittal fon- tanelle. This closes during foetal life, but the parietal foramina are remains of the interval. Sometimes a parietal fissure persists. The two centres may develop separately. The frontal bone is developed from two centres in membrane, appearing at the seventh week. At birth the bone consists of two lateral portions : the frontal suture ossifies from below upward, usually during the second year. The frontal sinuses appear about the seventh year and increase to old age. The fontanelles are membranous intervals between the incomplete angles of the parietal and neighboring bones, They are six in number — two median and four lateral. The anterior is quadrangular, placed between four bones, with its most acute angle pointing toward the nose; the posterior is trian- gular, is filled at birth, but the bones are freely movable. The lateral ones, are irregular intervals at the inferior angles of the parietal. All traces of them should disappear before the age of four. The temporal bone late in foetal life consists of three parts — squamo-zygo- matic, petro-mastoid, and tympanic — developed from ten centres : the squamo- zygomatic is developed in membrane from a single centre. From the squa- mosal a post-auditory process grows down between the tympanic and petro- mastoid portions, and forms the upper part of the mastoid division of the bone. In the third month a nucleus appears in the membranous wall of the tym- panum and forms the tympanic ring, an imperfect circle open above and en- closing the tympanic membrane. The petro-mastoid, or ear-capsule, is de- veloped in cartilage. The styloid process is formed from two centres in cartilage : the one near the extremity remains small till puberty, not joining the other till adult life or remaining separate. At birth the mastoid portion is flat, the antrum is present, the glenoid fossa shallow, the tympanic ring and membrane are even with the outer surface of the bone. The external auditory meatus is devel- oped by an outward projection of the tympanic ring, commencing as two tubercles : these meet on the floor of the meatus, enclosing a foramen which is not obliterated till the fifth year. This part always remains thin, or a small aperture may persist. The sphenoid is divided in the foetus into a post-sphenoid part, to which the sella Turcica, great wings, and pterygoids belong, and a presphenoid part, which includes the body in front of the olivary eminence and the small wings. It has twelve centres in all, one for each pterygoid plate, each lin- gula, each carotid groove. The sphenoidal spongy bones begin to ossify at the fifth month. They entirely surround the sphenoidal sinus by the third year ; then their upper and inner parts absorb. They are ankylosed first to the ethmoid (fourth year) ; hence some regard them as parts of that bone ; they join the sphenoid at the ninth to twelfth year. The ethmoid has three centres, one for each lateral mass and one for the ver- tical plate ; the cribriform comes from all three sources. The superior maxilla, clavicle, and lower jaw begin to ossify at about the same time, fifth to the seventh week. The number of centres is uncertain, but there seem to be four pieces — a malar portion, orbito-facial, palatine, and a premaxillary for the bone carrying the incisor teeth. The antrum appears at the fourth month. The infraorbital canal begins as a groove, which is closed by the growing over of the outer margin : a fine suture remains to indicate the line of meeting. The palate bone has a single centre. EXTERNAL SURFACE OF THE SKULL. 63 The vomer has two nuclei in membrane ; they unite below, but above and in front form two laminae. The nasal and lachrymal bones each have a separate centre : the lateral car- tilage of the nose continues up beneath the nasals ; it subsequently disappears. The malar bone has three centres : a continued separation of one of them gives rise to a bipartite bone occasionally seen. The inferior turbinate has a single centre in cartilage at the fifth month. The inferior maxillary bone is developed in the fibrous tissue investing Meckel's cartilage: thefergest part is formed in membrane outside this car- tilage. A small part of the body near the symphysis ossifies directly from Meckel's cartilage ; the condyle, part of the ramus, and the angle also ossify in cartilage, the last not connected with Meckel's, which runs up to the fissure of Glaser continuous with the slender process of the malleus, and it eventu- ally forms the internal lateral ligament of the lower jaw. What are some of the points of difference between human and animal skulls? (1) The proportionally large expansion of the cranial bones in the human skull ; (2) the smaller development of the face and jaws, all of which are under the brain-case; (3) adaptation of the cranium to the erect posture. The occipital condyles are at a point about -^ of the distance from the posterior to the anterior extremity of the head, but this part is heavier than the anterior, and therefore nearly balanced. The foramen magnum looks down ; in quadrupeds it is posterior and looks back ; in anthropoid apes it is intermediate in direction. The downward openings of the nostrils, forward aspect of the orbits, vertical forehead, and oval face are in strong contrast with the small cranium and strong crests of the animal. In late years the vertebrate theory of the skull tends to be abandoned. What are some of the various forms of skull ? According to Age : in the foetus the posterior part is large and the face is not one-eighth of the cranial bulk, while in the adult it is one-half. The skull grows rapidly during the first seven years; at puberty there is a second period of growth affecting face and air-sinuses. Sexual Differences: the female skull is smaller, smoother, and lighter than the male ; the cranial cavity is less by one-tenth. Race Differences : the capacity normally varies from 60 to 110 cubic inches (1000 cc. to 1800 cc), with an average in all races of 85 cubic inches (1400 cc). Skulls exceeding 87 cubic inches (1450 cc.) are megacephalic— Europeans and Eskimos. Skulls below 80 cubic inches (1350 cc.) are microcephalic— Australians. Skulls between 80 and 87 cubic inches (1350 and 1450 cc.) are mesocephalic— Chinese. What are the names of certain fixed points on the skull ? Alveolar point, centre of upper alveolar arch. Subnasal point, middle of anterior nasal aperture. Nasion, middle of naso-frontal suture. Ophryon, middle of that supraorbital line which separates the face from the cranium. Bregma, point of junction of coronal and sagittal sutures. Obelion, point in the sagittal suture between the parietal foramina. Lambda, point of junction of sagittal and lambdoid sutures. Occipital point, median point of occiput most removed from glabella. 64 . BONES OF THE UPPER EXTREMITY. InioHj external occipital protuberance. Opisthion, middle of posterior margin of foramen magnum. JBasion, middle of anterior margin of foramen magnum. Pterion, spheno-parietal suture. Lower stephanion, where lower temporal line crosses the coronal suture. Upper stephanion, where the upper temporal line crosses the coronal suture. Asterion, lateral angle of occipital bone. Auricular point, Qentre of orifice of external auditory meatus. What are some of the measurements of the cranium ? Maximum circumference (horizontal), 21.7 inches (550 mm.); minimum, 17.7 inches (450 mm.) ; average in adult European male, 20.5 inches (525 mm.), in female, 19.5 inches (500 mm.). The proportion of the breadth to the length on a scale of 100 is the cephalic nidex : Skulls with a breadth-index above 80 are brachycephalic. Skulls with a breadth-index from 75 to 80 are mesaticephalic. Skulls with a breadth-index below 75 are dolichocephalic. The breadth is usually taken as four-fifths the length. The gnathic index expresses the degree of projection of the jaws. Similarly, there are the nasal index, orbital index, etc. Irregularities of form are a result of too early ossification of sutures : scaphocephaly is a result of obliterated sagittal suture; acrocephaly is due to obliterated coronal suture; plagiocephaly is oblique deformity. BONES OP THE UPPER EXTREMITY. Shoulder j ^„^Iv^,^]^ [ 5 forming shoulder-girdle. Arm (brachium), humerus. Upper limb, \ Forearm (antibrachium), radius and ulna. ( carpus. Hand (manus) < metacarpus. (phalanges. THE SHOULDER. Describe the clavicle. The clavicle (key) passes out, back, and sUghtly upward from the sum- mit of the sternum to the acromion, and connects the upper limb to the trunk. It is curved like the letter/ for purposes of elasticity and ad- mission of vessels behind it. The inner curve is convex forward, and occupies two-thirds of the bone : this part is prismatic. The outer third of the bone is concave in front and is flattened from above down. The superior surfaces of these two portions are continuous ; the infe- rior surfaces are continuous ; the anterior border of the outer portion runs into the anterior surface of the inner ; and the posterior border of the outer is continuous with the posterior surface of the inner. The superior surface is broad externally and largely subcutaneous ; at its cen- tre it may present a canal for the supraclavicular nerve ; the sterno-cleido- THE SHOULDER. ^^^pLUB^ mastoid is attached to the inner part. The anterwr surface is reduced to a rough border on the outer portion, where it jives attachment to the deltoid, and mav present a deltoid tubercle. Tfifi PV^tori^iH|i«j«i<)r J* ^ 1 attached to the 'inner half. I *-""wUN, Mi Ui | The posterior surface is a border externally aid gives attachment to the trapezius. In the middle of this surface is Ihe orifice of a medul- lary canal directed outward. (In bones having bu\)ig^secondary centr^^^ the medullary artery runs from it. ) Internally thi^ra^^ce gives j attachment to the sterno-hyoid muscle. ^ ^^w!^E, ^^^jl^ The inferior surface shows internally a rough 'im'pYeSSf9nimt^!ostal tuberosity about 1 inch long, for the rhomboid ligament ; internal to it is a small facet for articulation with the cartilage of the first rib ; external to it, a groove passing beyond the middle third for the subclavius mus- cle : the groove may show a longitudinal ridge for an intermuscular sep- tum. On the posterior border, at the junction of the outer and middle thirds, is the conoid tubercle (scapular tuberosity), and passing out and forward from it the trapezoid line. The sternal end is thick and projects in an angle down and backward, its triangular concavo-convex surface looking a little downward and for- ward. The scapular end is so bevelled as to rest upon the acromion, the small articular surface looking down and out : this end is normally a little higher than the acromion on which it rests. This bone is a fulcrum to enable muscles to give lateral motion to the arm : it is absent in animals whose fore limbs are used only for progression — e. g. horse and bear ; in carnivora it is not attached to bone ; it is the furculum or *' wish-bone " of birds. The female clavicle is smoother and more slender than the male. The right clavicle is usually rougher and shorter than the left. It is developed from two centres : one is the earliest in the body to ap- pear, fifth week, and the secondary centre at the sternal end is the last in the body to appear, twentieth year. Describe the scapula. The scapula (spade) extends from the second to the seventh rib or seventh interspace. It is attached to the trunk only by muscles, is ar- ticulated with the clavicle, and from it is suspended the humerus in the shoulder-joint: its posterior border is about 1 inch from, and parallel with, the vertebral spines ; its anterior surface looks forward, down, and in. The bone consists of a large triangular blade or body, and two pro- cesses, the coracoid and spine, and presents for examination two surfaces, three borders, and three angles. The anterior surface, or venter, pre- sents the subscapidar fossa, marked by three or four converging oblique lines, giving attachment to tendinous intersections of the subscapular muscle. The deepest part of the fossa is the subscapular angle, where the bone seems bent on itself, so that the thickest part of the muscle is perpendicular to the plane of the glenoid cavity, and can act most advan- tageously. Separated from this fossa are two flat surfaces, one at the upper angle and one at the lower : with the line connecting them close to the vertebral border they give attachment to the serratus magnus muscle. 5— A. 66 BONES OF THE UPPER EXTREMITY. The posterior surface^ or dorsum^ is divided by the spine into two unequal fossae, the supraspinous and wfraspinous. The supraspinatus muscle rises from the inner two-thirds of the upper fossa. The lower fossa is marked near the centre by a convexity corresponding to the concavity of the venter ; on either side of this is a groove, the external one being deep and bounded by the axillary border. Near the inner border are short lines for intermuscular septa of the infraspinatus mus- cle, which rises from the inner two-thirds and covers the outer third. Along the outer part of this surface is a ridge passing down and back to the inner border, about 1 inch above the inferior angle : it gives attach- ment to the aponeurosis between the infraspinatus and teres muscles. On the upper third of the narrow surface between this line and the axillary border is a groove for the dorsalis scapulae vessels ; the middle third and part of the upper give attachment to the teres minor. Below this, in- cluding the inferior angle, is a raised surface for the teres major, over which the latissimus dorsi glides or attaches a few fibres. An oblique line separates the origins of the two teres muscles. The S27i)ie of the scapula is a triangular plate projecting back and up from the dorsum. Beginning near the upper fourth of the vertebral border, it passes up across the doi*sum to the middle of the neck of the scapula, and turns forward into the acromion process. The upper and lower surfaces are concave and form parts of the two dorsal fossae. It has two unattached borders, a posterior subcutaneous one and an exter- nal axillary one. The former rises from the vertebral border by a tri- angular surface, over which a tendon of the trapezius glides as it passes to its insertion into a rough tubercle beyond. (This tubercle is very large in animals. ) The rest of this border is rough and serpentine, and gives attachment by a superior lip to the trapezius, by an inferior lip to the deltoid. The external border is short, smooth, and concave, enclosing the great scapular notch. The acromion process projects out and forward over the glenoid fossa : it is compressed from above down ; its superior surface is rough, subcu- taneous, and continuous with the prominent border of the spine. An- teriorly on its inner border is an oval articular facet for the clavicle : to this border is attached the trapezius, to the outer border the deltoid, marked by three or four tubercles for tendinous septa. This outer border terminates posteriorly in the acromial angle. The coraco- acromial ligament is attached to the apex of the acromion. The coracoid process rises at fii-st almost vertically from the upper border of the head, compressed from before backward : it then bends at a right angle forward and outward. Superiorly, toward its base, is the origin of the conoid ligament, and the trapezoid rises from an oblique line running forward and outward. The coraco-acromial ligament is at- tached to the outer border, the conjoined tendon of the coraco-brachialis and biceps to its apex, and the pectoralis minor to its inner border. The tip of the coracoid is about one and a half inches distant from the apex of the acromion. THE ARM. 67 The external angle of the scapula is the thickest part of the bone : it is called the head, supported on a neck. The head bears the glenoid cavity : this is slightly concave, looks outward, forward, and slightly up- ward. It is pyriform, with its narrow end above, and measures If inches by J \ inches (40 mm. by 30 mm.). Above it is a supraglenoid tubercle for the long head of the biceps. The "anatomical neck" is the part just behind the head. The superior angle of the scapula is -thin and rounded, and gives at- tachment to some fibres of the levator anguli scapulae. The inferior angle is thick and rough for the teres major attachment, sometimes the latissimus dorsi. The superior border is shortest, and extends from the superior angle down to the coracoid, at the base of which is the suprascapular or coraco-scapular notch. A line through the suprascapular and great scapular notches marks the "surgical neck" of the bone. The axillary border is the thickest. Beneath the glenoid fossa is a rough tubercle or ridge, infraglenoid^ over an inch long, for the long head of the triceps. On the ventral aspect of this border is a longitu- dinal groove from which the subscapular muscle rises in part. The vertebral border is the longest, and gives attachment above the triangular surface at the apex of the spine to the levator anguli muscle, opposite the triangular surface to the rhomboideus minor, and below this to the rhomboideus major. The body of the scapula is mostly thin and translucent, and has no can- cellated tissue in those spots. Vascular foramina pierce the upper and lower surfaces of the spine and the anterior surface near the neck. The human scapula is remarkable for its length. All mammals possess scapulae. The coracoid reaches to the sternum in birds. The bone is developed from seven centres and is ossified in two principal parts, one for the body and one for the coracoid, which represents the large coracoid bone of lower vertebrates. The various epiphyses should be joined to the bone at the age of twenty-five. Sometimes the acromion and spine do not unite, and a joint with hyaline cartilage and synovial membrane may here be present. THE ARM. Describe the humerus. The arm-bone extends from the shoulder to the elbow. It is divisible into an upper extremity, including head, neck, great and small tuber- osities, a shaft, and inferior extremity, which includes condyles, epi- condj^les, and articular surface. The head forms one-third of a sphere of ^\ inches (32 mm.) radius, but the margin is not a true circle : a line from the upper part of the articular surface down and back to the lower part is 2 inches (50 mm.). A transverse diameter at right angles to this is If inches (44 mm.). The head is directed up, in, and a little back- ward, and makes an angle of 140° with the shaft. The "anatomical 6S BONES OF THE UPPER EXTREMITY. neck ' ' is the slight constriction at the circumference of the articular sur- face ; the " surgical neck " is below the tuberosities. The great tuberosity is a thick projection starting up from the external surface of the shaft. It is marked above by three facets, the upper for the supraspinatus tendon, the next for the infraspinatus, and the lowest for the teres minor, which also is attached to the shaft to the extent of 1 inch. Separated from this tuberosity by the hidpital groove (inter- tubercular sulcus, f inch (10 mm.) broad) is the small tuhet^osity^ looking forward and inward and giving attachment to the subscapularis. The shaft is thick and cylindrical above, expanded transversely and three-sided below. It is divided into external, internal, and posterior surfaces by anterior and lateral borders. (Henle describes it as having two surfaces and two borders.) Superiorly is the bicipital groove lodg- ing the long tendon of the biceps and a branch of the anterior circum- flex artery. This groove, descending, is bounded by rough margins, the external or pectoral ridge (spina tuberculi majoris) for the pectoralis major muscle, and the internal for the latissimus dorsi and teres major muscles : these muscular attachments end at the junction of the upper with the lower three-fourths. The anterior border is the pectoral ridge continued to the coronoid de- pression below. It becomes rounded and smooth below, and gives at- tachment to the brachialis anticus muscle. The inner border is the inner bicipital ridge continued to the inner condyle, called below the internal supracondylar ridge. About the centre of this border is a rough linear mark for the coraco-brachialis muscle, and just below it the orifice of the medullary canal directed downward. The external border runs from the back part of the great tuberosity to the external condyle. Its centre is traversed by the broad spiral groove.^ hmited above by the deltoid eminence and below by the external supracondylar ridge^ The ridge gives origin by its upper two-thirds to the supinator longus muscle; hence it is called the supinator ridge^ which is very large in burrowing animals : its lower third attaches the extensor carpi radialis longior. The posterior lip of either supracondylar ridge is for the triceps, and a middle portion for intermuscular septa. The external surface presents near its middle the deltoid eminence. The internal surface is narrow above, and forms the bicipital groove; near its centre is the insertion of the coraco-brachialis. Below this level the external and internal surfaces are occupied by the brachialis anticus. The posterior surface is twisted, so that its upper part is directed a little inward, its lower part backward and outward. It is nearly all covered by the external and internal heads of the triceps, which are separated by the spiral groove running down and out. At the upper part of this groove is generally a second medullary foramen for a branch of the superior profunda artery. The inferior extremity is flattened from before backward and curved THE ARM. 69 slightly forward. The two condyles include the articular surface, sepa- rated by a rounded ridge ; the inner condyle is five-sixths articular. The prominent tuberosities situated on either condyle are the epicon- dyles^ developed from separate centres. The internal epicondyle is the more prominent one, is inclined backward, and forms posteriorly a shal- low groove for the ulnar nerve. It gives attachment to the pronator radii teres and the common tendon of the superficial pronato-flexor mus- cles of the forearm. The external condyle presents (1) the epicondyle, which gives origin to some of the supinato-extensor muscles of the forearm ; (2) below and internal to this on the condyle a small impression for the anconeus ; and (3) a pit for the external lateral ligament. The inferior articular surface is divided into two parts : the external part, rounded and directed forward, is the capitellum for articulation with the radius ; it does not extend at all on the posterior surface. In- ternal to it is a groove for the inner margin of the head of the radius. The internal portion, or trochlea, articulates with the ulna, and extends from the anterior to the posterior surface of the bone ; the external bor- der is rounded and corresponds to the internal between the radius and ulna. The internal border is thick and prominent. Anteriorly these mar- gins are inclined down and inward, posteriorly up and outward, so that the groove is obliquely inclined from without inward, and if continued would form the thread of a screw. The external part of the trochlea is the segment of a sphere, the internal part the segment of a truncated cone with base internal ; at the junction of the cone and sphere is the groove. Above the trochlea posteriorly is the olecfranon fossa, above it ante- riorly the coronoid fossa : the thin plate between them may be perforated by the supratrochlear foramen. This occurs more often in the lower races of man and in the gorilla. Above the capitellum is the radial fossa for the head of the radius in flexion. The average length of the adult male humerus is 13 inches, female, 12 inches. It is nearly one-fifth the height of the individual. The right hume- rus with the radius is usually i to f inches longer than the left ; no differ- ence at birth. The shaft of the humerus is twisted through about 135°. The twist is seen at the spiral groove, " groove of torsion," which does not exist in the foetus ; this allows the hand to serve the purposes of the head and mouth. A small hooked supracondylar process is sometimes found about 2 inches above the inner epicondyle. A fibrous band connects it to the inner epicondyle and gives origin to the pronator radii teres muscle ; through the arch beneath pass the median nerve and brachial artery. Kemains of this foramen are seen in a fibrous band connected with the pronator muscle in about 45 per cent, of cases. The humerus is developed from seven centres ; the upper epiphysis unites last. 70 BONES OF THE UPPER EXTREMITY. . THE FOREARM. Describe the ulna. This is the internal of the two bones of the forearm. A line passing from the tuberosity of the humerus through the capitellum touches the lower end of the ulna. It is the arm-bone, while the radius is the hand- bone. The ripper extremity presents two processes and two articular concav- ities. The great sigmoid cavity^ articulating with the trochlea, looks upward and forward, and is bounded above by the olecranon and below by the coronoid processes ; it is concave from above down, and is trav- ersed by a longitudinal ridge which is a half-circle of f inch (10 mm.) radius. The part external to the ridge is broad and convex above, the part internal is broad and concave below. A slight constriction is seen across the middle of the cavity. Continuous with it is the small sigmoid cavity on the outer side of the base of the coronoid : it is concave from before backward for the head of the radius. The olecranon terminates in front in a beak which overhangs the great sigmoid cavity ; behind it is a rectangular tuberosity, forming the point of the elbow. It has supe- riorly a ligamentous district, next a bursal, and next a tendinous one for the triceps. The posterior surface of the olecranon is triangular and sub- cutaneous, and continuous with the posterior border of the ulna. The extremity of the coronoid process is sharp and pointed. Its superior sur- face is a part of the great sigmoid cavity. At the inner part of the junc- tion of the coronoid to the shaft of the ulna, also to the tuberosity of ulna at the angle of junction, is attached the brachialis anticus muscle, not into the process. Arising from the process is one head of the flexor sublimis digitorum, the flexor profundus, pronator radii teres, and occa- sionally the flexor longus pollicis. The shaft or body tapers from above, is three-sided in its upper three- fourths, slender and cylindrical in its lower fourth. The upper three- fourths are convex backward ; it is also convex externally above and in- ternally below. The anterior border passes from the inner edge of the coronoid to the front of the styloid : it is thick and rounded, and gives attachment to the flexor profundus digitorum, and in its lower fourth to the pronator quadratus. The posterior border begins below the olecranon, and runs with a sinuous curve to the back of the styloid. It is ill defined below and sub- cutaneous throughout, and affords attachment to an aponeurosis common to three muscles — the flexor carpi ulnaris, extensor c. ulnaris, and flexor profundus. The external or interosseous border is a sharp edge in the middle three-fifths of the shaft. ^ Below it is faintly marked. The upper one-fifth is continued by two lines passing to the extremities of the small sigmoid notch : the posterior line is prominent, supinator ridge^ for the supinator brevis muscle. The anterior surface is concave above, and gives origin to the flexor profundus digitorum : the lower one-third is marked by the oblique pro- THE FOREARM. 71 nator ridge, which joins the anterior border. Above the middle is a medullary foramen directed upward. The internal surface is smooth, and gives attachment to the flexor profundus digitorum muscle : it is subcutaneous in the lower one-third. The posterior surface looks outward and backward : an oblique line de- scending from the supinator ridge to the posterior border at the junction of its upper and middle thirds marks oiF a triangular area for the an- coneus muscle. The ridge itself gives attachment to the supinator brevis. Below this is a longitudinal ridge dividing the surface into a smooth inner portion covered by the extensor c. ulnaris, and an outer part impressed from above downward by the extensor ossis metacarpi pollicis, extensor secundi internod. poll. , and extensor indicis. The inferior extremity presents a rounded head : from its inner and back part there projects downward the styloid process, giving attachment to the internal lateral ligament and to the triangular fibro-cartilage. Be- tween the head and styloid process is a groove for the tendon of the ex- tensor carpi ulnaris. The head has two articular surfaces — an inferior one, upon which the triangular fibro-cartilage plays, and an outer narrow convex one, for the sigmoid cavity of the radius. With the hand supine the styloid process projects at the inner and back part of the wrist : if pronated, the outer and fore part of the ulnar head is prominent between the tendons of the extensor c. ulnaris and extensor min. digiti. The ulna is developed from^ three centres : the greater part of the olecranon grows by an extension from the shaft. Describe the radius. This bone articulates with the humerus, ulna, scaphoid, and semilunar bones. The superior extremity, or head (eminentia capitata), is disk- shaped. On its summit is a depression for the capitellum of the hume- rus. It is surrounded by a convex part, broadest internally, which rotates in the small sigmoid cavity of the ulna within the orbicular ligament. The head is supported by a nech, which presents behind a ridge for part of the insertion of the supinator brevis. The shaft is larger below than above, slightly curved, and convex out- ward and backward. Antero-internally below the neck is the bicipital tuberosity, rough posteriorly for the insertion of the biceps, and smooth in front for a bursa. Below this tuberosity the shaft has three surfaces and three borders. The anterior border extends from the tuberosity to the base of the styloid : its upper part is called the anterior oblique line, and gives at- tachment to the supinator brevis, flexor longus poUicis, pronator radii teres, and flexor sublimis. The posterior border runs from the back of the neck to the posterior part of the base of the styloid. It is well marked only in its middle third. The internal or interosseous border becomes prominent below, and at ^2 BONES OF THE UPPER EXTREMITY. its lower part divides into two ridges which meet the margins of the sigmoid cavity, analogous to the division of a like border of the ulna. The anterior surface is grooved longitudinall}^ for the flexor long. poll, muscle: at the lower end is a flattened impression for the pronator quadratus, which also rises from a small surface at the inner side of the bone. A medullary foramen is above the middle of this surface. The posterior surface shows at the junction of the upper and middle thirds the posterior oblique line, below which is attached the extensor ossis metacarpi poll., and below that the extensor primi internodii poll. The external surface is convex, and marked near the middle by an impression for the pronator radii teres : above this, on the area be- tween the anterior and posterior oblique lines, is inserted the supinator brevis. The lower extremity of the radius, broad and quadrilateral, presents a carpal articular surface and an ulnar articular surface. The former is divided by a line into a quadrilateral inner part for the semilunar, and a triangular outer part for the scaphoid. The articular surface for the ulna or sigmoid cavity is at right angles to the inferior surface, and concave from before backward. To the smooth border between these two articular surfaces is attached the base of the triangular fibro- cartilage. Externally the styloid process projects downward. Ante- riorly a transverse ridge forms the lowest limit of the pronator quad- ratus impression, which is continued into a vertical ridge external to that impression: between this ridge and the scaphoid facet is a tri- angular area for a strong band of the anterior ligament. The ex- ternal and posterior aspects are marked by the following grooves from without inward : a flat groove for the extensor ossis met. poll, and ex- tensor prim, internod. (next descends the styloid process) ; a broad groove, subdivided by a slight ridge, for the extensor carpi rad. longior and brevior ; an oblique narrow groove, bounded externally by a tubercle, for the extensor secundi internod. poll. ; a broad groove for the extensor indicis, extensor communis, and extensor min. dig. Just above the first groove is an impression for the supinator longus. The relative length of the forearm to the arm is expressed by the humero- radial index : Eskimo, 71 (i e. the radius is 71 if the humerus be taken as 100); European, 74; gorilla, 80; orang, 100. The index is higher in the foetus and infant. The radius in bats and birds is very long and supports the wing. The radius is developed from three centres. All the epiphyses around the elbow unite earlier than those at the opposite ends of the bones. THE HAND. The skeleton of the hand consists of three segments — wrist-bones, bones of palm, and bones of fingers. Describe the carpus, or wrist-bones. The carpus is composed of eight short bones arranged in two rows : the upper row, from radial to ulnar side, comprises the scaphoid, lunar THE HAND. 73 (semilunar), pyramidal (cuneiform), and pisiform; in the inferior row are the trapezium, trapezoid, os magnum, and unciform. The dorsal surface of the carpus is convex, and palmar concave transversely ; the concavity is bounded by four prominences (eminentiae carpi), one at each end of each row, to which the anterior annular ligament is attached. The superior surfaces of the scaphoid, lunar, and pyramidal form a me- niscus for articulation with the concavity presented by the radius and triangular fibro-cartilage. The mid-carpal articulation is concavo-con- vex, the trapezium, trapezoid, and os magnum forming a concavity for the scaphoid, while the unciform and head of the os magnum rise up in a convexity. Each bone is more or less cubical and presents six surfaces. The scaphoid (boat-like) has its long axis directed down and out. Internally it has two articular facets, a lower one for the os magnum and an upper crescentic one for the lunar. The superior surface is smooth and triangular, passes farther back than forward, and articulates with the radius. The inferior surface is smooth and convex, divided by a ridge, articulating externally with the trapezium and internally with the trapezoid. The anterior surface is concave above, and presents a conical tuberosity below. The external surface is rough and narrow. The pos- terior surface is a narrow transverse groove. The lunar bone is characterized by a deep concavity from before back- ward on its inferior surface ; it is for the head of the os magnum. This surface also presents a long narrow facet for the unciform. Externally it is crescentic and vertical for the scaphoid. Its internal surface looks down and in, is narrower than the external, and articulates with the pyramidal. The convex upper surface is four-sided, articulates with the radius, and extends farther back than forward, so that the anterior free surface is deeper than the posterior. The pyramidal (cuneiform) bone directs its blunted apex down and in. The base shows a flat quadrilateral surface for the lunar. The in- ferior surface is concavo-convex from without inward, and articulates with the unciform. The anterior surface has a small articular facet on its inner half for the pisiform. The supero-posterior surface has near the base an articular facet for the triangular fibro-cartilage, but is mostly rough for ligaments. The pisiform (like a pea) is anterior to the other bones of the carpus. It is spheroidal, with longest diameter directed vertically. Posteriorly is is an oval facet for the pyramidal, leaving a free portion below. The inner surface is convex and rough ; the outer, toward the flexor tendons, is smoother and slightly concave. The trapezium (a table) is the most external of the second row. The supero-internal surface is concave and ^articulates with the scaphoid. The inferior surface, directed down and *out, is concavo-convex for the first metacarpal, The internal surface articulates with the trapezoid, and on its lower inner angle with the second metacarpal. The anterior surface is marked by a vertical groove for the flexor carpi radialis tendon, 74 BONES OF THE UPPER EXTREMITY. external to which is a ridge or tuberosity for the annular ligament. The anterior, external, and dorsal surfaces are free. The trapezoid is much smaller than the trapezium ; its longest diam- eter is from before backward, and its posterior surface is larger than its anterior. The external inferior angle of the anterior surface is pro- longed backward between the smooth surface for the trapezium and that for the second metacarpal bone. The superior surface is quadrilateral and articulates with the scaphoid ; the external is convex for the tra- pezium ; the internal articulates with the os magnum ; and the inferior concavo-convex surface with the second metacarpal. Hold the bone with the larger non-articular surface toward j^ou and the smooth quadri- lateral articular surface upward (for scaphoid) ; the convex articular sur- face (for the trapezium) will point to the side to which the bone belongs. The OS magnum (os capitatum) is the largest of the carpal bones, rec- tangular below and rounded above. The upper extremity, or head^ ar- ticulates with the lunar, its smooth surface extending farther behind than in front, and prolonged upon its outer side for the scaphoid. The nech is formed by depressions anteriorly and posteriorly. The anterior surface is narrower than the posterior. The posterior surface projects down- ward at its internal inferior angle. Externally, below the surface for the scaphoid, is a facet for the trapezoid. On the posterior part of the in- ner surface is a vertical facet for the unciform. Inferiorly there are three facets, the middle being the larger, for the second, third, and fourth metacarpal bones. The unciform (hook-hke) bone is wedge-shaped, with its base or infe- rior surface resting on the fourth and fifth metacarpal bones : its apex points up and out and articulates with the lunar. The external surface is vertical, and articulates with the os magnum by its upper posterior part. Its supero-internal surface is concavo-convex for the pyramidal : it is separated from the inferior surface by a rough border. The anterior surface at its lower and inner side presents the unciform process^ pro- jecting forward and curved slightly outward. ARTICULATIONS OF CARPAL BONES. Scaphoid . . Lunar . . . Pyramidal . Pisiform Trapezium . Trapezoid. . Os magnum Unciform. . Superior. External. radius radius triangular fib. cart, free scaphoid scaphoid scaphoid lunar lunar free scaphoid lunar free free trapezium trapezoid OS magnum Inferior. trapezium trapezoid 08 magnum unciform unciform free 1st metacarp. 2d metacarp. 2d,3d, and 4th metacarp. 3d and 4th metacarp. | Internal. OS magnum lunar pyramidal free Ante- rior. free free pisi- form free free free trapezoid 2d metacarp OS magnum free unciform free pyramidal free Posterior. free free free pyramidal free free free free Num- ber. 5 5 THE HAND. 75' The carpus is wholly cartilaginous at birth : each bone is developed from a single centre except the scaphoid. The nucleus of the pisiform does not ap- pear till the twelfth year, the latest of all primary centres. In the foetus the scaphoid has normally a second cartilaginous element, which may develop into the os centrale placed on the back of the carpus between the scaphoid, os magnum, and trapezoid. The styloid process of the third metacarpal may be separated as a supernumerary bone. Describe the metacarpus, or bones of palm. The metacarpus supports the fingers and consists of five long, sHghtly divergent bones. They form the segment of a transverse arch : their carpal extremities are expanded bases and their digital ends are rounded heads. The first metacarpal is broad and short, the second longest of all, while the third, fourth, and fifth decrease regularly in length. The shafts are curved longitudinally, and are three-sided, presenting a pos- terior surface and anteriorly a median margin between two lateral sur- faces. They are more slender near the carpal ends and thicker toward the heads. The dorsal surface is triangular, being bounded by lines which proceed from the sides of the head and converge in the second, third, and fourth metacarpals opposite the middle of the carpal extremity. The heads articulate with the proximal phalanges : their smooth surfaces broaden and extend farther on the palmar than on the dorsal aspect. On each side is a tubercle, with a hollow below it for attachment of the lateral ligament. The carpal extremities present distinctions. The first bone has a saddle-shaped articular surface, and externally a prominence for the insertion of the extensor ossis metacarpi poll. The shaft is com- pressed and dorsal surface convex. On the palmar surface the rounded ridge is nearer the inner than the outer border. The carpal extremity of the second is notched for the trapezoid. On the radial side is a facet for the trapezium, and close to it an impression for the extensor carp, rad. long. A prominent ulnar lip with two long facets is the distinguish- ing feature. The third bone presents a styloid process on the posterior radial angle, passing up behind the os magnum, and below it an impres- sion for the extensor carp. rad. brev. The radial side has one facet and the ulnar side two. The carpal extremity of the fourth has two facets on the radial side, and a concave semielliptical one on the ulnar side. The fifth has a saddle-shaped surface for the unciform, and a tuberosity on the ulnar side for the extensor carpi ulnaris. There is only one oblique ridge on the dorsal surface, extending from the radial side of the head to the ulnar side of the base. The first metacarpal articulates at its base with 1 bone. The second metacarpal articulates at its base with 4 bones. The third metacarpal articulates at its base with 3 bones. The fourth metacarpal articulates at its base with 4 bones. The fifth metacarpal articulates at its base with 2 bones. It is interesting that the corresponding metatarsals articulate with ex- actly the same number. 76 BONES OF THE LOWER EXTREMITY. Describe the digital phalanges. The phalanges (internodia) are fourteen in number, three for each finger and two for the thumb. Those of the first row, five in number, are sHghtly curved. The dorsal surface is transverse!}^ convex, while the palmar is flat and bounded by rough margins. Their metacarpal extremities are thick and present a transversely concave surface ; their distal extremities are smaller and divided by a median groove into two condyles. The bones of the middle roiv are four in number, and smaller than the preceding: their proximal articular surfaces show a middle ridge and two lateral depressions. The distal ends are like those of the first row. The terminal or ungual phalanges are five in number: their proximal extremities are like those of the middle, but with a depression in front for the deep flexor. Their free extremities are flat and expanded, and raised round the margins of the palmar aspect into an ungual process. Where are the sesamoid bones of the hand? One pair, each i inch (5 mm.) in diameter, is placed in the palmar wall of the metacarpo-phalangeal joint of the thumb ; others, single or double, may occur in the corresponding joint of the index and little fingers, more rarely in the third and fourth. Collectively, the phalanges of the middle finger are longest, then those of the ring, index, little finger, and thumb. In some hands the index is longer than the ring, due wholly to the length of the metacarpal bone. The metacarpals and phalanges are formed each from one centre for the shaft, and one for an epiphysis. In the four inner metacarpals the epiphyses are at the heads ; in the metacarpal of the thumb and in the phalanges the epiphyses are at the bases. The so-called first metacarpal therefore resembles a phalanx. The ungual phalanges are peculiar in beginning to ossify at the distal extremities instead of in the middle. In the metacarpals the medul- lary foramen is on the radial side of the palmar surface, and the canal runs toward the base ; in the phalanges and first metacarpal the canal runs toward the head of the bone. BONES OP THE LOWER EXTREMITY. The lower limb consists of the haunch or hip, thigh, leg, and foot. In the haunch is the hip-bone, in the thigh the femur, in the leg the tibia and fibula, at the knee a large sesamoid bone, the patella, in the foot the tarsus, metatarsus, and phalanges. The pelvis and hip-bone are a part of the lower extremity. THE PELVIS. Describe the hip-bone. The hip or innominate bone (os coxae), with its fellow, the sacrum, and coccyx form the pelvis. This bone is constricted in the middle and expanded above and below ; it has been likened to the shape of a meat- chopper. THE PELVIS. 77 The acetabulum is on the outer aspect of the constricted portion, and the inferior expanded portion is perforated by the thyroid or obturator foramen. The bone above forms part of the abdominal wall, and below part of the true pelvis. In early life the ilium^ pubes, and ischium are distinct. The ilium [ilia^ flanks; ileum is a part of the small intestine) is the su- perior expanded portion, and forms less than two-fifths of the acetab- ulum. This portion is limited anteriorly and posteriorly by margins which diverge at right angles from each other, and superiorly by the arched crest of the ilium. In front the crest is concave inward and behind it is concave outward : there is a marked external projection in the ante- rior third. On the crest are external and internal lips and a median ridge. The anterior extremity projects as the anterior superior spine; below it is a concavity, the lesser iliac notch., and below that the anterior inferior spine. Behind, the projecting extremity of the crest is called the posterior superior spine^ sej)arated by a small notch from the poste- rior inferior spine., below which is the great sciatic (ilio-sciatic) notch. The external surface or dorsum ilii presents three curved gluteal lines. The posterior or superior one commences 2 inches in front of the poste- rior superior spine, and curves down and forward to the back part of the ilio-sciatic notch. The middle gluteal line begins in front about 1 J inches behind the anterior superior spine, and arches back and down to the upper part of the notch. The inferior gluteal line, less strongly marked, commences just above the anterior inferior spine, and passes back to the fore part of the notch. Behind the posterior line is a semilunar surface, rough above for the gluteus maximus : the sickle-shaped space between the posterior and middle lines and iliac crest is occupied by the gluteus medius ; the gluteus minimus is between the middle and inferior lines. Just above the acetabulum is an elongated mark for the reflected head of the rectus femoris. The internal surface is divided into two parts : the anterior part is the iliac fossa or venter ilii. To the inner side of the anterior inferior spine is a shallow groove, the greater iliac notch, which lodges the ilio- psoas muscle : the inner boundary of the groove is the ilio-pectineal emi- nence, marking the junction of the pubis and ilium. The posterior part (sacral surface) h again divided, presenting from below upward (1) a smooth surface in the true pelvis, separated from the iliac fossa by the iliac portion of the ilio-pectineal line ; (2) the auricular surface, for articu- lation with the sacrum; (3) depressions on the iliac tuberosity, for the posterior sacro-iliac ligament ; (4) a rough surface giving origin to the erector and multifidus spinae muscles. The iliac crest gives attachment by its outer lip to the tensor vaginae fem- oris, obliquus externus, latissimus dorsi, and fascia lata; by its middle ridge to the obliquus internus ; by its inner lip to the transversalis, quadratus lum- ])orum, erector spina?, and iliac fascia. To the anterior superior spine is attached externally the tensor vaginse femoris, in front the sartorius, and internally Poupart's ligament. From the anterior inferior spine originates the straight 78 BONES OF THE LOWER EXTREMITY. head of the rectus : just below this is an impression for the ilio-femoral liga- ment. The iliac part of the ilio-pectineal line gives attachment to the iliac and obturator fasciae and tendon of the psoas parvus. The OS pubis forms the anterior wall of the pelvis, and bounds the thyroid foramen above. It forms about one-fifth of the acetabulum : at its inner extremity is a long oval surface marked by transverse ridges or nipple-like processes for articulation with the opposite bone ; the junc- tion is the symphysis pubis. The part passing down and out from the symphysis is the descending ramus ; the upper part is the superior or ascending ramus ; and the flat portion between the rami is the body. The pelvic surface of the body is smooth, the' anterior surface rough. The upper extremity of the symphysis is the angle; extending out from this on the superior border is the crest,, terminating in the spane. The descending ramus is thin and flat, and joins that of the ischium at the pubo-ischiatic tuberosity. The superior ramus becomes prismatic : its superior border is the pubic portion of the ilio-pectineal line^ running from the spine of the pubis to the ilio-pectineal eminence. The triangular surface in front of this line gives origin to the pectineus muscle : below is the obturator crest, extending from the pubic spine to the margin of the acetabulum. Behind the outer part of the crest on the inferior sur- face of the ramus is the obturator groove^ directed from behind forward and inward : it is limited by the //(/enbr and superior obturator tubercles. The pubic crest gives origin to part of the conjoined tendon, the pyramidalis and rectus abdominis. To the pubic spine is inserted Poupart's ligament and the outer pillar of the external abdominal ring. From the front of the pubis, in the angle between the crest and symphysis, rises the adductor longus mus- cle, and below this the adductor brevis and part of the adductor magnus. Internal to these the gracilis is attached, and external the obturator externus. Posteriorly the pubis gives attachment to the obturator internus : above this is sometimes a faint line passing from the upper margin of the obturator for- amen to the lower end of the symphysis ; the levator ani muscle is attached to it, and the obturator and recto- vesical fasciae. The ischium forms the lower and back part of the hip-bone, bounds the thyroid foramen below, and forms over two-fifths of the acetabulum. It presents a body, and below this a tuberosity continued forward into the ramus. The body has three surfaces, external, internal, and posterior. The external surface helps form the acetabulum ; below this and above the tuberosity is a horizontal groove for the tendon of the,obturator ex- ternus muscle. The internal surface is smooth, and forms part of the wall of the true pelvis. In front it is separated from the iliac fossa by the iliac portion of the ilio-pect. line, but behind the junction of the ischuim and ilium does not reach that line. The posterior surface is quadrilateral, getting narrow below, and continuous with the tuberosity. It presents a part of the groove for the obturator externus, and sup- ports the pyriformis, the two gemelli, and the obturator internus. On the posterior border is the spine, projecting back and in, and form- ing the inferior limit of the Uio-sciatic notch. THE PELVIS. 79 The small sciatic notch is between the spine and tuberosity. The tuberosity presents two lips and an intermediate space. The external lip gives attachment to the quadratus femoris and adductor magnus ; the inner Hp to the falciform portion of the great sacro-sciatic Hgament, and more anteriorly to the transversus perinei and erector penis. The inter- mediate space is divided into two portions : the anterior part attaches the adductor magnus externally and great sacro-sciatic hgament in- ternally ; the posterior part has two facets, an upper and outer for the semimembranosus, a lower and inner for the biceps and semitendinosus. The ramus joins the descending ramus of the pubis at the inner side of the thyroid foramen. Its outer surface gives attachment to the obtu- rator externus, adductor magnus, and gracilis. The crus penis, and above that the constrictor urethrae, are attached to the inner border. The acetabulum, or cotyloid cavity, is cup-shaped, and looks out, down, and forward. It is nearly surrounded by a prominent rim which presents three depressions — a slight one anteriorly and posteriorly, and the cotyloid notch below. In the lateral and upper parts of the cavity is a broad horseshoe-shaped articular surface. From the anterior corner of the horseshoe run two lines, one up and forward as the obturator crest to the pubic spine, the other backward to the superior obturator tubercle. The^ central part of the cup and the notch are depressed (fossa acetabuli), and contain fat and the interarticular ligament. This non-articular surface belongs mostly to the ischium. The thyroid or obturator foramen (foramen ovale) is internal to and below the acetabulum. It is nearly oval in the male, more triangular in the female. It is closed by fibrous membranes, except in the region of the obturator groove in its upper margin. The hip-bone is strongest along lines of greatest pressure. There is a thick bar on the ilium from the auricular surface to the acetabulum, also a second in the ischium and its tuberosity, and another running up from the acetabulum to the most prominent part of the crest. The iliac fossa and floor of the ace- tabulum are very thin : vascular foramina perforate the thickest parts of the bone. There may be an accessory ischial spine in the great sacro-sciatic notch. The pelves of most Javanese women present a preauricular sulcus for the anterior sacro-iliac ligament, rarely developed in European women. The OS innominatum is developed from eight or more centres in three prin- cipal pieces. By the seventh or eighth year the three pieces are separated by a Y-shaped cartilage in the acetabulum, which begins to ossify by the twelfth year from several centres : the most constant gives rise to a triangular os ace- tabuli, which forms the whole of the pubic portion of the articular cavity. Between the ilium and ischium are some irregular nodules, and a lamina spreads over the iliac and ischial portions of the articular surface. Secondary centres appear for the crest of the ilium, the tuber ischii, the anterior inferior spine, and symphysis: all are joined to the main bone by the twenty-fifth year. Describe the pelvis as a whole. The pelvis (basin) is composed of four bones — two ossa innominata, the sacrum, and coccyx. It is divided into two parts by a plane passing 80 BONES OF THE LOWER EXTREMITY. through the sacral promontory, ilio-pectineal lines, and upper border of symphysis. This circle is the inlet or brim of the true pelvis : the space above it really belongs to the abdomen, but is called the false or upper pelvis. The pelvic outlet presents three large prominences, the coccyx and tuberosities of the ischia. Beneath the symphysis and between the ischial tuberosities is the subpubic arch ; behind the tuberosities are the sacro-sciatic notches. What is the position of the pelvis ? In the erect attitude, with the heels together and toes turned out, the plane of the brim forms 60° with the horizontal, that of the outlet 16°. The base of the sacrum is about 3 J inches above the upper margin of the symphysis, and the tip of the coccyx about i inch above the apex of the subpupic arch. The sacrum looks down and forward, and is the inverted keystone of an arch, as its pelvic surface is broader than the dorsal : it is held in place chiefly by ligaments and by a slight bony pro- jection into the iliac articular surface (Fig. 12). What are the differences according to sex? In the female the bones are more slender and muscular impressions less marked ; the height is less, breadth and capacity greater ; but the false pelvis is relatively narrower than in the male. The sacrum is wider and flatter, less prominent, the subpubic arch is wider, about 90° (male is 75°), and the space between the ischial tuberosities is greater. The thyroid foramen is broader and more triangular in the female, nearly oval in the male. The characteristics of the human pelvis compared with that of lower ani- mals are its shallowness and breadth, great capacity of true pelvis, expansion of ilia, straightness of ischial tuberosities, and shortness of symphysis. The pelvis of the kangaroo is so small that the young are born when li inches long, and placed in a pouch on the abdomen of the mother, with the nipple firmly fixed in their mouths. THE SACRUM AND COCCYX. (See FalseVertdjrce, p. 28.) THE THIGH. Describe the femur. The femur (thigh-bone) is the largest, longest, and strongest bone of the skeleton. In the erect position it inclines inward and shghtly back- ward. It is divisible into a superior extremity^ including head^ nech^ and two trochanters; shaft; and inferior extremity^ expanded into external and internal condyles and epicondyles. The nech extends upward, inward, and slightly forward, being set upon the shaft at an angle of 125°. It is compressed from before backward, is broad at its base, becomes rounded at its summit, and enlarged as it joins the head. It is shorter above and in front than below and behind. Posteriorly it usually shows a shallow groove for the obturator externus THE THIGH. 81 tendon. Reasons for a neck are — ( 1) to transmit shock through an arch ; (2) room for adductor muscles ; (3) room for pelvic muscles to femur. The head forms more than half a sphere : its posterior inferior quad- rant shows a depression (fossa capitis), the fore part of which gives attachment to the interarticular hgament (lig. teres) of the joint. In this hollow are one or two vascular foramina. The great trochanter (to turn) is a thick process prolonged upward in a line with the external surface of the shaft to a level about i or f inch below the head. In front it is marked by a broad depression for the 'gluteus minimus. Externally an oblique line runs downward and for- ward, indicating the inferior border of the gluteus medius insertion. Lower down is a horizontal line continued to the tubercle of the femur ^ which is situated in front at the junction of the neck with the tuberosity : the tubercle is the meeting- place of five muscles — vastus externus, gluteus minimus, obturator internus, and two gemelli. Internally, at the base of the trochanter and rather behind the neck, is the digital fossa, giving attachment to the obturator externus tendon. Above and in front of this is the insertion of the obturator internus and gemelU muscles. The upper border of the trochanter is narrow, and presents an oval inark for the pyriformis. The posterior border is prominent, and con- tinuous with the posterior lutertrochanteric line, limiting the neck poste- riorly. Above the centre of this line is the tubercle o/ the quadratus, for attachment of the upper part of the quadratus femoris: sometimes a Itnea quadrati passes vertically down from the tubercle. The small trochanter is a pyramidal eminence projecting from the postero-internal aspect of the bone at the junction of the neck with the shaft. Its apex gives attachment to the ilio-psoas tendon. Anteriorly the neck of the femur is separated from the shaft by the anterior intertrochanteric line, which is the upper part of the spiral line (does not connect the trochanters) : it commences at the tubercle of the femur, and runs down and in a finger's breadth in front of the small tro- chanter : it gives attachment to the capsular ligament, the united crureus and vastus internus muscles. The shaft is arched with its convexity forward : toward the middle it is partly cylindrical, and expanded below. It presents anterior and lateral surfaces without definite lines of demarcation. All these surfaces are covered by the crureus and vasti muscles. Behind the lateral surfaces are separated by the linea aspera. This is a prominent ridge extending along the middle third of the shaft, bifurcating above and below. The external lip is prolonged up to the great trochanter : its upper end is strongly marked for the gluteus maximus, constituting the gluteal ridge. The inner lip winds round below the small trochanter, merging into the anterior intertrochanteric line and forming the lower part of the spiral line : rising from the inner lip, a third fine passes up to the small tro- chanter and gives attachment to the pectineus. Inferiorly two lips are prolonged to the condyles as the internal and external supracondylar lines, enclosing the flat popliteal surface of the 6— A. 82 BONES OF THE LOWER EXTREMITY. femur. The inner line is interrupted where the femoral vessels lie against the bone, and terminates below in the adductor tubercle. Above the centre of the linea aspera is the medullary foramen, directed upward ; a second may exist near the lower end of the bone. To the inner lip of the linea aspera is attached the vastus internus, to the outer lip the vastus externus, and diagonally between the two the adductor magnus. Between the adductor magnus and vastus externus are the gluteus maximus and short head of the biceps ; between the adductor magnus and Vastus internus are the iliacus, pectineus, adductor brevis, and adductor longus. At the lower part of the popliteal space above each condyle is the origin of one head of the gastrocnemius, and externally of the plantaris. The inferior extremity presents two rounded condyles^ united in front, but separated behind by the intercondylar notch : the external is broader and more prominent in front, the internal longer and more prominent internally. The inner aspect of this condyle and the head of the femur face nearly the same direction. The inferior surfaces of the two condyles are on the same level in the natural position of the femur. Opposite the front of the intercondylar notch the whole articular surface is divided by a faint transverse groove on either side into three parts — a convex surface on either condyle for the tibia and a grooved anterior surface for the patellar. The patellar surface is trochlear in form, marked by a vertical hollow and two lips : the external portion is wider, more prominent, and rises higher. The tibial surfaces are nearly parallel, but the internal one turns outward to meet the patellar surface. The exposed lateral surface of each condyle presents a tuberosity or epicondyle for ligamentous at- tachment. The external is the smaller : above it is the impression for the outer head of the gastrocnemius ; below and behind it is an oblique groove ending inferiorly in a pit from which rises the popliteus muscle ; its tendon sinks fully into the groove only when the knee-joint is flexed. The inner head of the gastrocnemius rises from the upper part of the inner condyle. The intercondylar fossa Y)resents two impressions for crucial ligaments: that for the anterior ligament is on the posterior part of the inner sur- face of the external condyle ; that for the posterior ligament is on the fore part of the external surface of the inner condyle. The cancellous tissue at the upper end of the femur is arranged in a system of " pressure lamellae " and " tension lamellae : " the former spring from the inner side of the neck and ascend to the head and to the great trochanter ; these are crossed at right angles by the tension lamellai, which start from the outer side of the shaft and pass upward and inward. The concave side of the neck is further strengthened by a vertical plate of compact tissue, the calcar femorale, just in front of the small trochanter. The average length of the adult European femur is 18 inches for the male and 17 inches for the female ; is .275 of the stature, and its proportion to the humerus is 100 : 71. The inclination of the femur is 9° with the sagittal plane (the two bones approach each other below) and 5° with the frontal ; it is also twisted in a direction opposite to that of the humerus. THE LEG. 83 The angle of the neck with the shaft is open in the foetus and child, then lessens under the weight of the body, but undergoes no change after growth is completed. The upper part of the gluteal ridge may form a third trochanter, always present in the horse. In place of or in addition to the ridge there may be a, fossa hypotrochanterica. A marked development of the linea aspera gives a pilastered femur. The ad- ductor tubercle may be of large size. The femur is developed from one primary centre and four epiphyses ; more of growth in length depends upon the lower epiphysis, as it unites last. Describe the patella. The patella, or knee-pan, is a sesamoid bone developed in the tendon of the quadriceps extensor cruris. It is somewhat triangular, with its apex below. Its anterior surface is convex and striated and pierced by vascular foramina. The superior border is broad and sloped from behind downward and forward, and gives attachment to the rectus and crureus portions of the quadriceps extensor. The posterior surface of the bone presents two vertical and two trans- verse ridges : one vertical ridge is close to the inner margin ; the other is distinct and divides the surface into two parts, the external of which is the larger and transversely concave, the inner smaller portion is convex. The faint transverse ridges divide the articular surface into an upper two-sixths, a middle three-sixths, and a lower one-sixth. In usual ex- tension the lower one-sixth is in contact with the femur, in mid-flexion the middle three-sixths, and in extreme flexion the upper two-sixths ; also in extreme flexion the thin marginal facet is the part in contact with the inner condyle. Below the articular surface is a rough triangular area ; the ligamentum patellae springs from the apex. In the third month there is a deposit of cartilage in the quadriceps tendon ; ossification begins from one centre in the third year and is completed at puberty. THE LEG. Describe the tibia. The tibia (flute), or shin-bone, is the inner and anterior of the two bones of the leg, and transmits the weight of the trunk to the foot. It articulates with the femur, fibula, and astragalus ; has a shaft and two extremities. The superior extremity, or head, is thick and broad transversely. It forms on each side a tuherosity, on the upper aspect of which is a con- cave articular surface for the condyles of the femur. The internal tuber- osity is larger than the external, and marked posteriorly by a horizontal groove for the semimembranosus. The external tuberosity at the junc- tion of the anterior and outer surfaces forms a prominent tubercle for the insertion of the ilio-tibial band ; below this are often attached a few fibres of the extensor longus digitorum and of the biceps. At the pos- terior and under part is a flat articular surface for the fibula, looking down, out, and back. The internal condylar surface is oval, more hoi- 84 BONES OF THE LOWER EXTREMITY. lowed than the external, and longer ; the external is nearly circular, con- cave from side to side, and more or less convex from before backward ; it is prolonged a little posteriorly where the popliteus glides. The periphery of each articular surface is flattened for the semilunar fibro- cartilage. Between the condylar parts is an interval depressed in front and behind for attachment of crucial ligaments, and elevated in the middle, forming the spine^ the summit of which presents two compressed tubercles with an intervening hollow. The depression behind the spine is continued into the popliteal notch, which separates the tuberosities posteriorly. Anteriorly, at the junction of the head and shaft, is the tubercle or ante- rior tuberosity for attachment of the ligamentum patellae. The shaft is three-sided, diminishing in size as it descends for about two-thirds of its length, and then increasing again. The internal surf ace is convex and nearly subcutaneous. At the inner side of the tubercle are the insertions of the gracilis, semitendinosus, and double insertion of the sartorius. The anterior border runs sinuously from the tubercle to the front of the inner malleolus : its upper two-thirds is the crest of the tibia, its lower third is smooth. The external surface is hollowed in its upper two-thirds, where it lodges the tibialis anticus ; below this the surface turns forward and is covered by the extensor tendons. The upper third of the posterior surface is crossed obliquely J3y the popliteal or oblique line, running down and inward : it gives origin to the soleus. Above it is a triangular area occupied by the popHteus; below it, in the middle third of the shaft, is a longitudinal ridge marking off two portions, an inner for the flexor long, dig., and an outer for the tibialis posticus. Below the oblique line a large medullary canal runs down- ward. The posterior surface is separated from the internal by the inter- nal border, which is most distinct in the middle third, from the external surface by the external border or interosseous ridge. The inferior extremity is broad from side to side, and projects down- ward internally to form the inner malleolus. This malleolus is marked posteriorly by a groove for the tibialis posticus tendon, and more exter- nally by a depression for the flex. long. poll. The external surface of the extremity is hollowed for the fibula, and rough for ligaments except along the lower border. Below is an articular surface, quadrilateral, concave, narrower behind than in front. It shows a slight median ele- vation separating two lateral depressions. Internally the cartilaginous surface is continued upon the inner malleolus. The ratio of the length of the femur to that of the tibia is 100: 81 in the European, or 100 : 86 in the Bushman. The tibia is twisted with an angle of torsion of 5° to 20°. The shaft may be much compressed laterally, so that the skin and posterior longitudinal ridge are very prominent ; such bone is platycneniic. A facet at the anterior margin of the inferior extremity for articulation with the neck of the astragalus is rare in Europeans, but common in lower races of men. THE LEG. 85 The tibia is developed from three centres: the secoudary one for the upper extremity usually appears before birth. The tubercle may have a separate centre. Describe the fibula. The fibula (clasp), or peroneal bone, nearly equals the tibia in length ; its purpose in the leg is mainly for elasticity. Its shaft is convex back- ward, and its lower extremity is placed a little in advance of the upper. The upper extremity, or head, is prolonged upward at its back part into the styloid process ; inside this is a facet looking upward, inward, and forward for articulation with the tibia ; more externally is a slight excavation for the biceps ; the peroneus longus is attached in front and soleus behind. A somewhat constricted part below the head is the neck. The lower extremity, or external malleohis, is pyramidal and longer than the internal malleolus ; internally it shows a triangular, smooth, articular surface for the astragalus, and behind this a depression for the posterior band of the external lateral ligament. Posteriorly is a shallow groove for the peroneus longus and brevis tendons. Externally this extremity is convex and subcutaneous. The shaft presents four surfaces — anterior, posterior, internal, and external; and four borders — antero-external, antero-internal, postero- external, and postero- internal (Gray). The antero-external harder begins in front of the head and bifurcates below to embrace the triangular subcutaneous surface of the external malleolus: this border is between the peroneal and extensor muscles. The antero-internal border, or interosseous ridge, is close to the pre- ceding and parallel with it in the upper third. It terminates below at the apex of a rough surface just above the articular facet. The attached interosseous membrane separates the extensors in front from the tibialis posticus behind. The postero-external border commences at the base of the styloid pro- cess and terminates below in the posterior border of the external mal- leolus. It is directed out above, then back, then slightly inward below. It separates the peronei from the flexor muscles. The poster o-internal border, or oblique line, commences inside the head, and ends by joining the interosseous ridge in the lower fourth of the bone. The anterior surface is very narrow above, broader and grooved below; to it is attached the extensor prop, poll., the extensor long, dig., and peroneus tertius. The external surface is directed outward above and backward below, and is occupied by the peroneus brevis and longus muscles. The internal surface between the antero-internal and postero-internal borders is grooved for the tibialis posticus. The posterior surface looks backward above and directly inward be- low.^ Its upper third attaches the soleu^ muscle ; its lower part is rouffh for interosseous ligaments ; to the rest of the surface is attached the 86 BONES OF THE LOWER EXTREMITY. flexor long. poll. The medullary canal opens on this surface and is directed downward. The fibula is developed from three centres : the centre for the lower epiph- ysis appears first and unites first, contrary to the general rule ; sometimes the medullary canal runs toward the knee. The fibula in the embryo is nearly as large as the tibia, is not twisted, and articulates with the femur. The tibial malleolus at first is larger than the fibular ; the prominence of the latter is acquired after birth. THE FOOT. Name the bones constituting the tarsus. The tarsus is composed of seven bones — the calcaneum or os calcis, and the astragalus, forming the hind-foot, the navicular or scaphoid, three cuneiform, and cuboid, forming the fore-foot. Describe the os calcis. The OS calcis (heel) is the largest bone of the foot : it articulates with the astragalus above and cuboid in front ; its principal axis runs down- ward and forward. The bone presents six surfaces. The posterior ex- tremity^ or tuberosity^ presents inferiorly two tubercles : the inner is the larger. Its posterior surface presents three districts — a smooth one for a bursa, a ligamentous one for the tendo Achillis, and a lower convex part for the pad of &EMIMEMB. SEMI M EM B. PLANTARIS GASTROCNEMIUS EXT. LAT^LIG. [short EXT [LATUQ BICEPS SOLEUS. Posterior Surface of Knee-joint. position the popliteus does the same, so that the ligament is tense in either case, and the canal held open by which the popliteal bursa com- municates with the joint. 3. Externally is the long ext. lateral ligament (lig. accessorium laterale), a flat strand separated from the capsule by fat. It rises from the exter- nal epicondyle, receiving some fibres from the external intermuscular septum, and passes straight to th^ head of the fibula, spliting the biceps tendon at its insertion. The most anterior fibres of this hgament bend at right angles to the front, and are lost on the edge of the external semi- lunar cartilage : it is tense in extension and relaxed in flexion. 4. Internally are two ligaments, long and short internal lateral (lig. access, mediale longum and breve). Both are from the epicondyle below the lateral patellar ligament : the long one is the more superficial and attached to the posterior edge of the inner surface of the tibia 2 to 3 inches (5-8 cm.) below its articular surface. It covers the inferior artic- ular vessels and the semimembranosus tendon, and is separated by a bursa from the tendons of the gracilis and semitendinosus ; posteriorly it becomes very thin. As this rises from about the centre of the circle 9— A. 130 ARTICULATIONS OF THE LOWER EXTREMITY. formed by the posterior part of the condyle, it has an equal degree of tension in flexion or extension. The short internal lateral ligament^ placed behind the long internal, is a continuation of the semimembranosus fibres vertically to the inner semilunar cartilage. What bursse are related to the joint ? Anterior Bursce. Prepatellar. 1. Subcutaneous. 2. Subfascial. 3. Subaponeurotic. Pretibial. 1. One in front of tubercle of tibia. 2. One between lig. patellae and tubercle of tibia. 3. Subpatellar. Suhcrural Bursa. Lateral Bursce. Internally. 1. Beneath inner head of gas- trocnemius. 2. Beneath semimembranosus. 3. Between semimembranosus and semitendinosus. Externally. 1. Beneath outer head of gas- trocnemius. 2. Beneath tendon of popliteus. 3. Between tendon of popliteus and ext. lat. lig. 4. Bicipital, between biceps, fib- ula, and ext. lat. lig. The nerves are from the obturator, anterior crural, by branches to the vastus externus, internus, and crureus, external and internal popliteal, three branches from each, and sometimes the great sciatic. The arteries are — the anastomotica magna of femoral, five articular of popliteal, recurrent anterior tibial, posterior tibial recurrent, and a de- scending branch from the external circumflex. Movements to be considered are those between each condyle and tibia, between femur and patella. It is a hinge, and owes its special motions to peculiarity of ligaments rather than to conformation of bone, as in case of elbow. Flexion and extension have a maximum of 140° : flexion is arrested mostly by the anterior crucial ligament ; the anterior fibres of the posterior ligament are also stretched. At the beginning of flexion both crucial ligaments become relaxed : both are stretched in extension, especially the posterior short fibres of the posterior crucial. In exten- sion the lateral ligaments are tense, and do not allow any motion but flexion. Flexion and extension do not occur in a pure hinge-like man- ner: the same part of one articular surface is not always applied to the same part of another ; the axis of motion is not a fixed one. The motion LIGAMENTS BETWEEN THE BONES OF THE LEG. 131 . of the femur on the tibia is likened to that of a carriage-wheel on the ground: it advances or recedes while it rotates. The semilunar cartilages are loosely attached, and move forward in ex- tension and backward in flexion of the joint like movable wedges ; as the condyles roll and present different curvatures, each cartilage contracts or expands to fit the surface above. The actual contact of the femur with the tibia is hardly more than linear. In extension the anterior capsular wall is raised by the subcrural mus- cle ; in flexion the posterior wall has two muscles to prevent its bulging- into the joint. The semimembranosus acts through its oblique ligament when the flexors from the thigh and pelvis are in operation ; the popli- teus, through the arcuate ligament when the plantaris and those at- tached to the OS calcis act. As flexion increases, rotation is possible, and increases to a total of 39°, due to a relaxation of lateral and crucial ligaments. Rotation out (supination) is most extensive, as the external lateral ligaments are more loose than the internal ; this occurs on an axis through the inner condyle and inner tuberosity of the tibia. This motion is checked by the internal lateral ligament and the winding of the posterior crucial around the spine of the tibia. Rotation in (pronation) on an axis through the outer con- d^de and outer tuberosity of the tibia is never more than 5° or 10°; this motion is checked by the anterior crucial Hgament and by the twisting of these crucial ligaments around each other. At the close of full extension there is a movement of adaptation^ or gliding back of the inner condyle upon the tibia : this axis is through the external condyle. At the beginning of flexion a reverse motion takes place. The movements of the patella are partly gliding and partly those of co- aptation. ^ In extension only the lower one-sixth of the patellar articular surface is in contact with the femur ; in semiflexion, the middle three- sixths ; in full flexion, the upper two-sixths, as the lig. patellae pulls it down in front of the joint. LIGAMENTS BET-WEEN THE BONES OF THE LEG-. Describe the ligaments between the bones of the leg. In the upper tihio-jihular articulation is a capsule and two accessory bands. The capsule rises from the tibia about ^ inch (5 mm. ) above the artic- ular surface, elsewhere from its edge ; it passes to the contiguous mar- gins of the fibular surface, and generally encloses a Httle space at the lower part of the joint, covered only by periosteum, where the tibia and fibula rest upon each other. Accessory hands are anterior and posterior ligaments (lig. capituli fibulae ant. and post). The former consists of one or more bands from the front of the head of the fibula to the front of the outer tuberosity of the tibia : some fibres of the peroneus longus and extensor long, digit. 132 ARTICULATIONS OF THE LOWER EXTREMITY. rise from it. The posterior ligament connects the bones in a similar manner, and is covered by one head of the soleiis. This joint-cavity may communicate with the knee-joint. Fat fills the space between the capsule and interosseous membrane. The joint- surfaces move in a transverse and sagittal direction, more in the former ; the purpose of the movement is to allow a gliding at the lower ends of the bones. Between the bones is the interosseous ligament or membrane, its fibres passing down and out to the fibula ; it separates the flexor from the ex- tensor muscles. Above is an opening for the anterior tibial vessels, and below another for the anterior peroneal. Close to the upper tibio -fibular joint is a band of fibres analogous to the oblique ligament of the fore- arm, running in a direction opposite to the fibres of the rest of the mem- brane. If the forearm be pronated and compared with the leg, the two interosseous ligaments run in parallel directions. * • The inferior tibio-fihular joint presents interosseous, anterior, posterior, and transverse ligaments. The interosseous is continuous with the inter- osseous membrane above. The anterior and posterior ligaments connect corresponding surfaces of the two bones. The transverse is under the posterior ligament, projects below and connects the margins of the bones, and forms part of the articulating surface for the astragalus. THE ANKLE-JOINT. Describe the ligaments of the ankle-joint. The ligaments are anterior^ posterior, intetmal lateral, and external lateral. The anterior is broad and thin, and connects the tibia and astragalus. The posterior consists mostly of transverse fibres between the tibia and astragalus. The internal lateral or deltoid has a superficial and a deep layer : the former rises from the apex, anterior and posterior borders of the internal malleolus, ^ and passes forward to the scaphoid and inferior calcaneo- scaphoid ligament, downward to the posterior edge of the sustentaculum tali, and backward to the astragalus, alltodifierent bones ; the deep layer is strong and thick, and passes from the apex of the malleolus directly to the inner surface of the astragalus. ^ The external lateral ligament has three fasciculi — one from the ante- rior -part of the external malleolus to the astragalus, a middle one from the apex of the malleolus to the os calcis, and a posterior one from the back of the malleolus to the astragalus. (For movements, etc. see p. 137.) JOINTS OF THE FOOT. What are the ligaments of the tarsus ? There are three sets — articulations of first row, of second row, of the two rows with each other. JOINTS OF THE FOOT. 133 Those of the first row, between the astragalus and os. calcis, are exter- nal^ internal^ and posterior calcaneo-astragaloid and interosseous. The external is in front of and parallel with the middle fasciculus of the ext. lat. lig. : it is inconstant and connects the outer surfaces of the two hones. The mternal passes from the inner tubercle of the astragalus to the sustentaculum tali. The posterior is narrow and connects the posterior borders of the two bones. The interosseous is thick and strong and fills the groove between the two bones. The ligaments of the second row are dorsal^ plantar^ and four inter- osseous. These include the scapho- cuboid ligaments. The ligaments connecting the two rows are of three sets — viz. (1) be- tween OS calcis and cuboid ; (2) between os calcis and scaphoid ; (3) be- tween astragalus and scaphoid. (1) Superior^ Internal, Long and Short Calcaneo-cuhoid. — The superior connects the upper surfaces of the two bones. The internal is some- what interosseous. The long plantar (long calcaneo-cuboid) passes from the tuberosities of the os calcis to the ridge on the under surface of the cuboid, completing a canal for the peroneus long, tendon. The short plantar extends from the anterior tubercle of the os calcis to the cuboid behind its peroneal groove. (2) The ligaments are superior and inferior calcaneo-scaphoid. The superior and internal calcaneo-cuboid form the arms of a Y. The inferior passes from the sustentaculum tali to the tuberosity of the scaphoid, forming an articular cavity for the head of the astragalus : it is supported below by the tibialis posticus tendon. (3) There is a thin superior astragalo-scaphoid ligament : an inferior ligament is supplied by the inferior calcaneo-scaphoid. What are the remaining ligaments of the foot ? Tarso-metatarsal joints have dorsal, plantar^ and interosseous liga- ments: the latter are three in number. The intermetatarsal articulations have dorsal, plantar^ and interosseous ligaments : the digital extremities are united by a transverse metatarsal ligament which connects the great toe to the others. Metatarso-phalangeal and interphalangeal articulations have each plantar and two lateral ligaments. HENLE'S CLASSIFICATION OF THE ANKLE- AND FOOT- JOINTS. The articulations of tlie ankle, tarsus, etc. are all described under one head, the "foot-joints." A division into capsular membranes and accessory bands cannot here be made just as in the hand : a ligament may pass over more than two bones, or one connecting two bones may help form a joint-socket. There are three dis- tinct movable joints to be considered — that of the ankle, the anterior and posterior astragaloid joints: all the others are amphiarthrodial. 134 ARTICULATIONS OF THE LOWER EXTREMITY. A. Lower Tibio-fibular Joint. A thin capsule is mentioned. Tlie interosseous ligament (membrane) ceases I inch (10 mm.) above the lower extremity of the tibia: this distance between the tibia and fibula is a space hardly deserving the name "joint-cavity." The tibial surface is covered with periosteum, the fibular with a flat pad of fat (" valved pad") interposed in the chink between the bones. This allows a *'give" in the joint: it is squeezed up between the bones and articulates be- low with the supero-external border of the astragalus, and prevents that bone from being pushed up between the tibia and fibula. Accessory bands, anterior and posterior dig. malleoli lateralis ant. and lig. mal. lat. post.), are continuous above with the interosseous ligament and be- low with the pufty edge of the capsule of the ankle. The anterior band is triangular, and passes down and out from the tibia in front of its articular surface to a corresponding point on the fibula. Anteriorly it is covered with fat and loose connective tissue: its posterior surface is in the ankle-joint, and its lower edge overhangs the astragalus. The posterior ligament resembles the anterior in shape, but is stronger ; rises not only from the posterior surfaces of the two bones, but also from their op- posing surfaces and from a deep fossa behind the articular surface of the fib- ula. These lowest fibres (transverse lig. of Gray) run to the inner malleolus of the tibia or are lost on its posterior capsular wall. Both accessory bands are tense in flexion of the foot and relaxed in extension. B. Joints of the Astragalus. Capsular Ligaments. — 1. Talo-crural Articulation. — Talus = astragalus, os navic- ulare = scaphoid. Surfaces are covered with hyaline cartilage 1 to 2 mm. thick ; the accessory bands of the lower tibio-fibular joint help form these joint sur- faces. The upper articular surface of the astragalus corresponds to a radius of ^ inch (17 to 21 mm.) and an arc of 120°; the extent of articular surface on the tibia is related to that on the astragalus as 2 : 3. Both head and socket di- minish in a transverse direction toward the posterior from 32 to 28 mm. The capsule is tense on the sides and loose anteriorly and posteriorly, where it is thrown alternately into folds in flexion or extension : it is attached close to the articular surfaces except in front of that on the astragalus, where it en- closes a rough space covered partly by fat and partly by thin periosteum. Vertical septa divide this little anterior pouch into compartments which com- municate with the general cavity only by narrow mouths. On the posterior capsular wall are hernia-like protrusions. The strengthening fibres on the posterior wall pass down and in ; on the anterior wall down and out. Thick fat pads lie upon the anterior and posterior capsular walls : the posterior is enclosed in fascia to which the plantaris is attached, so that this pad and the capsule are pulled back when that muscle contracts. 2. Posterior Astragalus Joint (astragalo-calcanea). — The surface on the os calcis is that of a cylinder of 1^ inches (26 mm.) radius, whose axis passes from the posterior edge of the outer surface of the bone to the antero-inferior edge of the inner, making an angle of 30° with the long axis of the foot. The head of the joint is on the calcaneum, the socket in the astragalus; and motion here is a rotation of the foot on its long axis. The capsular membrane is close to the articular surfaces in the region of the interosseous groove, elsewhere is farther away : it is in relation to fatty masses, especially so near the canalis tarsi. 3. Anterior Astragalus Joint (astragalo-calcaneo-scaphoidea). — This is a joint of cylindrical surfaces : the head includes the anterior surfaces of the astrag- JOINTS OF THE FOOT. 135 alus and the anterior part bf its lower surface ; the socket is made of the in- ner articular surface of the os calcis, the posterior surface of the scaphoid, and the lig. tibio-calcaneo-naviculare (inferior calcaneo-scaphoid), and its fibro- cartilage. A horizontal section of the head shows an arc of 120° ; a vertical section is a little smaller. The lig. tibio-calcmieo-naviculare fills up the space in the plantar arch on the inner edge of the foot between the scaphoid and OS calcis : it is made up of fibres which pass forward from the groove on the astragalus for the flex. long. poll, tendon, fibres passing down and forward from the tip of the inner malleolus, down and back from the scaphoid, up and forward from the sustentaculum tali. At the junction of all these fibres there is an elliptical ligamentous disk ^ inch (6 mm.) thick, hard like car- tilage, and may be ossified in spots. This supports the head of the astragalus, preserves the arch of the foot, and forms a groove for the tibialis posticus tendon. The socket of this joint presents three zones : (1) corresponds to the postero- internal articular surface on the sustentaculum tali ; (2) divided also into three parts, (2') the antero-internal articular surface on the calcaneura, (2") the lig. tibio-calc.-naviculare, (2'") the ligamentous disk of this ligament; the third (3) zone is the anterior wall of the socket and belongs to the sca- phoid. All these bony surfaces are marked oflT by deep furrows and fatty synovial folds. The joint-head also presents three zones nearly corresponding to the above. The capsule of this joint springs inferiorly close from the edges of the artic- ular surfaces, superiorly at some distance from the edges, and internally it reaches under the tibio-calc.-navic. lig. close to the ankle-joint. Accessory Ligaments. — Of the astragalus joints there are three groups : (1) those connecting the astragalus with the bones of the leg ; (2) those connect- ing the astragalus and os calcis ; (3) that between the astragalus and scaphoid. The external are usually longer and stronger than the internal. I. Ligg. Talo-cruralia. — These pass two from each malleolus obliquely down to the astragalus, one backward and one forward on each side. They hold the astragalus so firmly under the tibia that no rotation about a sagittal axis is possible. By flexion of the foot the two posterior are stretched, by exten- sion the two anterior. 1. Lig. Talo-fibulare Posticum, the posterior fasciculus of the ext. lat. of Gray ; origin, fossa on fibula behind its articular surface ; insertion, posterior surface of astragalus near the outer tubercle of .the flex. long. poll, groove. 2. Lig. Talo-tibiale Posticum (posterior superficial fibres of deltoid), from a little fossa behind the tip of inner malleolus to a smooth place on the astrag- alus below the posterior half of the joint-surface. 3. Lig. Talo-fibulare Ant. (anterior fasciculus of ext. lat. lig.), external malleolus to astragalus, 10 mm. broad; may divide into two at its insertion. 4. Lig. Talo-tibiale Ant. — Short band, 3 mm. broad, deeply placed under other ligaments ; passes from apex of inner malleolus to a point behind the rounded apex of the inner joint-surface of the astragalus. II. Ligg. Talo-calcanea. — 1. Lig. Talo-calcaneum Posticum springs by a point from the outer tubercle of the flex. long. poll, groove, and is inserted broadly or by two arms into the upper and inner surface of the os calcis. 2. Lig. Talo-calcaneum Laterale. — Ext. calc.-astragaloid of Gray ; from upper and outer surface of os calcis, covered by the short extensor muscle, passing through the fat at the entrance of the sinus tarsi, upward, inward, and back- ward to the rounded margin of the astragalus, which overlies the canalis tar- si. It is frequently doubled and frequently lacking. 3. Lig. Talo-calcaneum Mediate, a small nearly horizontal slip from the inner 136 ARTICULATIONS OF THE LOWER EXTREMITY. margin of the flex. long. poll, groove to the posterior edge of the sustentaculum tali. 4. Lig. Talo-calcaneum Inter osseum (interosseous calcaneo-astragaloid). — This fills the tarsal canal ; consists of several layers and mostly short fibres. In the narrowest part of the canal two layers cross each other obliquely. III. Lig. Talo-naviculare are dorsal fibres between the neck of the astragalus and middle of the scaphoid : it has two parts, which lie beside each other on the astragalus and overlap on the scaphoid, the external lying upon the inner ones, and some going on to the middle cuneiform. IV. Long Accessory Bands between Bones of the Leg and Tarsus. — 1. Lig, Tibio- naviculare (ant. superficial fibres of deltoid), from the anterior edge of inner malleolus down and out to the dorsum of the scaphoid. 2. Lig. Calcaneo- fibular e (middle fasciculus of ext. lat. lig.), from the apex of the external malleolus to a little tubercle in the middle of the external surface of the os calcis : it is covered by smooth membrane and helps form a groove for the peroneal tendons : it may be doubled. 3. Lig. Calcaneo-tibiale (middle superficial fibres of deltoid), from inner malleolus to posterior edge of sustentaculum tali. C. Amphiarthrodia of Tarsus. First row — astragalus and os calcis ; second row = scaphoid and posterior half of cuboid ; third row = the cuneiform bones and anterior half of cuboid. Capsular membranes are variable in number, but should be nine ; they are tense, and grow close to the edges of the joint-surfaces. The synovial folds are fatty and small. There is a capsule for (1) the calcaneo-cuboid joint; (2) the cuneo-navicular, which also includes the articulations of the cuneiform with each other, the external cuneiform with the cuboid, the navicular with the cuboid (sometiraes) ; (3) tarso-metatarsal joints: capsules usually three in number — one for the internal cuneiform and first metatarsal, one for the mid- dle and external cuneiform and second and third metatarsals, the third for the cuboid and fourth and fifth metatarsals. Accessory Bands of Tarsus. — I. On Dorsal Surface. — 1. Transverse : (a) in sec- ond row, ligg. naviculari-cuboidea, a superficial and a deep one; (&) in third, row, (1) ligg. cuneo-cuboid., an anterior and a posterior one ; (2) between second and third cuneiforms; (3) between second and first, (c) In the metatarsus, ligg. intermetatarsea dorsalia, lacking between the first and second. 2. Sagittal : (a) between first and second rows, (1) lig. calcaneo-naviculare dor sale = superior calcaneo-scaphoid ; (2) ligg. calcaneo-cuboidea dorsalia, two or three bands = superior and internal calcaneo-cuboid ; (6) between second and third rows, (1) between scaphoid and outer cuneiform; (2) scaphoid and middle cuneiform, two bands ; (3) scaphoid and inner cuneiform, two strong bands ; (c) between third row and metatarsus, ligg. tarso-metatarsea dorsalia; one to the first metatarsal from the internal cuneiform; three to the second, one from each cuneiform ; to the third are variable bands, may be two from the two outer cuneiform ; to the fourth, one, sometimes two, from the cuboid ; to the fifth, one from the cuboid. II. Accessory Bands of Plantar Surface. — There are long bands which are superficial and pass over several bones ; short bands which are deep and con- nect adjoining bones, {a) Long Ligaments. — Lig. calcaneo-cuboideum plantare = plantar ligaments of Gray. This rises from the whole rough under surface of the OS calcis from the two posterior tubercles to the anterior one : it is divisible into three layers. The most superficial passes over the tuberosity of the cuboid to the flexor brevis poll, muscle, to the interossei and bases of the metatarsal. These last fibres are strengthened by single bundles rising JOINTS OF THE FOOT. 137 from the tuberosity of the cuboid : the fibres to the flexor brevis poll, are joined by transverse fibres from the tendon of the tibialis posticus, and are also connected' with the plantar fascia. The middle set of fibres extends to the tuberosity of the cuboid. The deepest set is inserted into the cuboid behind its tuberosity, passing mostly from the anterior tubercle of the os calcis : it comes to view internal to the upper layers. The lig. tarseum transversum laterale goes from the external cuneiform, cov- ered by the peroneus longus tendon, to the tuberosity of the fifth metatarsal. The lig. tarseum transversum mediale runs from the inner surface of the inner cuneiform to the base of the third, sometimes fourth, metatarsal. {b) Short Ligaments. — 1. Transverse: (a) in second row, lig. cuboideo-naviculare plantare; (&) in third row, between the cuboid and outer cuneiform and be- tween the cuneiforms is a continuous band or several separate ones ; (c) in the metatarsus, ligg. intermetatarsea plantaria, only between the four outer bones : the lack of one between the first and second is supplied by a band from the internal cuneiform to the base of the second. 2. Sagittal : (a) between first and second rows, lig. calcaneo-naviculare plan- tare, a short round band running obliquely inward and forward to the navic- ular bone from ^the anterior inner corner of the os calcis ; (b) between the second and third rows, from the scaphoid to the cuneiforms, a broad band covered by the tibialis posticus tendon ; (c) between the third row and meta- tarsus, ligg. tarso-metatarsea plantaria, a broad and strong band to the first from the inner cuneiform; weak bands to the second from the middle and outer cuneiforms; to the third, short bands from the middle and external cunei- forms and cuboid ; to the fourth, a band from the outer cuneiform or from the cuboid, or from both. 3. Accessory Bands in the Interspaces of the Metatarsus. — Ligg. intermetatarsea interossea lie in the spaces just in front of the capsules in which the side sur- faces of the bases of the metatarsals articulate with each other. What separate synovial cavities are there? Usually six — one for the posterior calcaneo-astragaloid joint; one for the anterior and the astragal o-scaphoid joint; one for the calcaneo-cuboid ; one for the cuneo-scaphoid, the cuneiform with each other, the external cunei- form with the cuboid, the middle and external cuneiform with the second and third metatarsals ; one for the first metatarsal and internal cuneiform ; one for the fourth and fifth and cuboid ; sometimes one between the scaphoid and cuboid. Nerves for ankle-joint proper are from anterior and posterior tibials : tarsal joints have the anterior tibial and plan tars. Arteries of ankle are anterior and posterior tibials, anterior and posterior peroneals; lower down are the plantars and dorsalis pedis. The movements of the ankle-joint are flexion and extension — a little lateral motion in extension : this is possible because the astragalus and tibio-fibular mortise are a little wider in front than behind, and in extension the nar- rowest part of the astragalus is in the widest of the articular socket. * In flexion, as in stepping upon a chair, where lateral motion would be dan- gerous, the two joint-surfaces fit closely. With flexion is associated a slight rotation out of the foot; with extension, a slight rotation in. Flexion, a lifting of the apex of the foot, is possible to 20° from the horizontal ; exten- sion, a depression of the apex of the foot, goes through 45°. Eversion or inversion of the foot means a rotation out or in of the whole lower extremity. Rotation out or in is rotation of the whole foot on a longi- 138 MYOLOGY. tudinal axis: this occurs at the posterior calcaiieo-astragaloid joint. The foot is rotated in when the sole looks in. Adduction or abduction refers to a. displacement in or out of the fore-foot, motion occurring in the tarsal joints, especially mid-tarsal. The movements between the lower ends of the tibia and fibula are those of elasticity. What are the ligaments of the metatarso-phalangeal joints ? Each has a capsule, which is connected with the other by ligg. capitulorum plantaria and dorsalia, which together form the transverse metatarsal liga- ment of Gray. It connects the great toe with the others. Under the joints it is developed into a thick fibrous or sesamoid plate. In the one for the great toe the plate is ossified into two bones held together by transverse, bands : this may occur in other toes. Besides the above there are two lateral liga- ments. As a rule, there is a bursa between the capsules in the three inner intermetatarsal spaces. The interphalangeal articulations are practically the same as those of the fingers. MYOLOGY. How are muscles divided? Into— I. Voluntary, striated (animal life) ; IT. Involuntary (vegetative life) — (a) smooth, non-striated, (Z)) striated (cardiac). Describe the structure of muscle. I. Primitive muscle Jihrillce form fibres ; fibres, fasciculi; fasciculi, muscles or flesh. Epimysium surrounds entire muscle, and sends partitions between fas- ciculi, called perimysium ; endomysium is between the fibres, but not as a sheath. ^ • The fibres average ^^ inch in diameter, 1 } inches long ; by volition may contract one-fourth or one-third of its length, by electricity three- fourths. They consist of (1) central contractile substance, (2) nuclei, (3) tubular sheath or sarcolemma: they are divisible into the primitive fibrillas, shown by longitudinal striations, and each fibrilla breaks into disks called sarcous elements^ dark in the centre, with a lighter zone at each end ; transversely through the light zone passes Kranses line, or membrane limiting with the sarcolemma each element ; Hensen^s line passes transversely through the central dark band. ^ Striated muscles comprise those of locomotion, respiration, expres- sion ; those of ear, larnyx, pharynx, tongue, upper half of oesophagus, and walls of large veins near heart. II. [a] Smooth, unstriped muscular fibres are made up of long nu- cleated cells, collected in bundles or layers, surrounded by connective tissue; the cell-body shows a longitudinal striation. This variety of PLATE IX. Fig. 1 . -— To fme page 138. Arrangement of Muscular Fibres in Muscles in relation to the tendons and muscular aponeuroses: t, t^, tendons of origin and insertion; My muscular belly ; a, 6, length of muscular belly (Beaunis and Bouchard). Fig. 2. — To face page 146. A Transverse Section of the Abdomen in the Lumbar Region. PLATE X. Fig. 1. — To face page 152. ■Superficial perineal artery. Superficial perineal nerve. Internal pudic nerve. Internal pudic artery. The Superficial Muscles and Vessels of the Perinseum. Fig. 2. — To face pages 158 and 159. A Jaw. B Trapezius. Median line. C Cla^dcle. D Diagram of the Triano'les of the Right Side of the Neck. MUSCLES OF THE TRUNK. 139 muscle is found in the lower part of the oesophagus, stomach, intestinal canal, spleen, trachea, bronchial tubes, gall-bladder, bile-duct, ducts of large glands, of sweat-glands, uterus, appendages, vagina, ureters, blad- der, urethra, corpora cavernosa, dartos, epididymis, prostate, ciliary muscle, iris, coats of veins, arteries, and lymphatics, (b) In striated heart-muscle the fibres anastomose and form a long-meshed network ; no sarcolemma: transverse striae are weak, fibres small, and made up of quadrangular cells joined end to end, each with a central nucleus. MUSCLES IN GENERAL. They are symmetrical in pairs, excepting the sphincters and a few others. They number about 31 1 (voluntary) : head and front of neck = 82, vertebral column and back of neck = 60, thorax = 42, abdomen = 14, upper hmb = 59, lower limb = 54. If a man weighs 150 pounds, his skeleton weighs 28 pounds ; muscles, 62 pounds (over 40 per cent. ) ; vis- cera, fat, blood, etc., 60 pounds. How are muscles named? (1) From situation^ as tibialis ; (2) direction^ rectus ; (3) use^ flexors ; (4) shape, deltoid ', (5) subdivision, biceps ; (6) attachment, sterno-cleido- masto-occipitoid ; (7) size, magnus; (8) bellies, digastric; (9) structure, semimembranosus; ('[0) relation to organs, extrmsiG or intrinsic ; (11) position, superficial or deep ; (12) name of describer, Horner's, Galen's. Some muscles are synergists to others, some antagonists, some mode- rators. The origin of a muscle refers to its more fixed, the insertion to its more movable or remote, attachment. The same nerves that supply joints gen- erally supply the muscles and integument over those joints. How are fasciae arranged? The superficial fascia is subcutaneous all over the body : its web con- tains subcutaneous fat, the panniculus adiposus, and often superficial muscles, the panniculus carnosus. There is no fat in this layer in the eyelids, penis, and scrotum. Beneath the fatty layer. is usually another, devoid of fat, for the support of vessels and nerves. The deep fasciae or aponeuroses are made of strong fibrous tissue cov- ering the body more or less, forming aponeuroses of investment or of in- sertion for muscles. Near some joints it is strengthened by transverse bands, forming retinacula or annular ligaments to hold tendons close to bone. MUSCLES OP THE TRUNK. MUSCLES AND FASCIA OP THE BACK. Describe the muscles of the back. (a) Superficial, running out from spinous processes. First Layer. — Musculus Trapezius (cucullaris), or hood muscle. — 140 MUSCLES OF THE TRUNK. Origin^ inner third superior curved line of occipital bone, lig. nuchas, spinous processes of the seventh cervical, and all the dorsal vertebrae and supraspinous ligament ; insertion^ fibres converge to shoulder girdle ; superior ones to outer third or half of posterior border of clavicle ; mid- dle fibres horizontally to inner margin of acromion and superior lip of scapular spine ; inferior fibres up and out to a triangular tendon gliding over the inner extremity of the spine and inserted into a tubercle at its lower posterior margin. The aponeuroses of the .two muscles form an ellipse widest at the seventh cervical spine. Varieties. — May not rise from lower six dorsal spines ; no occipital attach- ment ; separation of cervical and dorsal parts ; vestige of panniculus carnosus superficial to it. ^ Second Layer. — 1. M. Rhomboideus Minor. — Origin^ seventh cer- vical and first dorsal spines and lig. nuchas of that region ; insej^tion, base of scapula opposite triangular surface at commencement of spine. 2. M. Rhomboideus Major. — Origin, spinous processes of four or five upper dorsal vertebrae and supraspinous ligament ; insertion, base of scapula between spine and inferior angle. The greater part of its fibres is not fixed directly to bone, but ends in a tendon attached to the lower angle of the scapula, so that the muscle acts more especially upon this angle. This muscle comes to view in the sixth intercostal space, with the scapula external, trapezius internal, and latissimus dorsi below. Variable in verte- bral and scapular attachments ; the division between the two indistinct. M. rhomboideus occipitalis (occipito-scapularis) above rhomb, min. from occiput beneath splenius to scapula, covering insertion of rhomb, min., normal in rabbits. 3. 31. Teres Major, not round. — Origin, dorsal aspect inferior angle of scapula, slightly from axillary border, from septa between it, the minor and infraspinatus, from infraspinatus fascia; insertion, by flat tendon, 2 inches wide, behind latissimus dorsi into inner bicipital ridge of humerus. The two tendons are united below for a short distance, but separated by a bursa at their insertion. May be connected with latissimus dorsi where it rises from the scapula ; a slip to the fascia of the upper arm externally. 4. M. Latissimus Dorsi, broad and flat at its origin, narrow at its in- sertion. — Origin, spinous processes of lower six or seven dorsal ver- tebrae, posterior layer of lumbar aponeurosis, which attaches it to the lumbar and sacral spines and iUac crest, from external lip of iliac crest in front of lumbar aponeurosis ; from last three or four ribs by digita- tions interposed between those of the external oblique ; usually by a slip from inferior angle of scapula. Its upper fibres are nearly horizontal, middle, oblique, and lower, vertical : it winds round the teres major and in front of it, and is inserted by a tendon 1} inches wide into floor of bi- cipital groove, a little higher than the teres major, and by its upper edge MUSCLES AND FASCIA OF THE BACK. 141 into the inner lip of the groove limiting the insertion of the subscap- ularis. Vertebral and costal attachments variable ; muscular bands, axillary arches from near the insertion across the great vessels and nerves to either the great pectoral tendon, coraco-brachialis, biceps, or fascia; a slip from lower ribs to coracoid = m. costo-coracoid ; a slip to triceps, fascia, or internal intermuscular septum = m. dorso-epitrochlearis of apes, usually present in man as a fibrous band. Third Layer. — Serrati Muscles. — 1. M. Serratus Posticus Superior. — Origin^ by a thin aponeurosis from two, rarely three, upper dorsal spines, supraspinous ligament, seventh cervical spine, lower part of lig. nuchge ; fibres pass down and out ; inserted by four slips into the upper borders and outer surfaces of the second, third, fourth, and fifth ribs beyond their angles. The slips may be three or increased to six. 2. M. Serratus Post. Inferior^ broader than the above. — Origin., by part of the lumbo-dorsal aponeurosis from first two lumbar and last two or three dorsal spines ; passing up and out ; inserted by four slips intx) the lower borders of the last four ribs up to the origin of the lat. dorsi. The two middle slips are broadest ; the others may be lacking ; they over- lap each other from above. Fourth Layer. — Mm. Splenii. — Named from strap-like action bind- ing down underlying parts ; rise from lower half of neck and upper half of back. 1. M. Splenms Capitis. — Origin^ lig. nuchse over third, fourth, fifth, and sixth cervical spines, from seventh cervical and first two dorsal spines ; insei^tion^ outer surface and posterior margin of mastoid process, outer part of superior curved line to insertion of trapezius. 2. 31. Splenitis Cervicis (colli). — Origin^ below the above from third, fourth, fifth dorsal spines, not lower than the sixth ; insertion^ with slips of levator ang. scap. into tips of trans, proc. of first and second, often third, cervical vertebras. The splenii are covered in part by the trapezius, rhomboidei, and superior serratus ; the complexus comes to view internal to them. The m. rhombo- atloideus, or splenius colli access., rises from the lower one or two cervical spines superficial to the superior serratus, inserted into the trans.* proc. of the atlas. M. splenius capitis access, is a similar slip ending on the occipital bone or mastoid. iVerves.— Trapezius by spinal accessory, third and fourth cervical n. ; rhom- boidei by fifth cerv. n. ; teres major by lower subscapular n. (6, 7 c.) ; latissi- mus dorsi by long subscapular n. (7, 8c.); serrati by intercostals or upper slip of ser. post. sup. by cervical plexus ; splenii by posterior spinal n. Actions. — Trapezius, upper part supports shoulder, raises point of shoulder by rotation of scapula, acts in forced respiration ; middle part adducts scap- ulae, helps elevate shoulder, throws chest out ; inferior part would alone de- press and carry scapulee in, but in concert with the upper two-thirds of the 142 MUSCLES OF THE TRUNK. muscle it raises acromion and carries lower angle out and up. Fixed below, one acting, draws head back and rotates face to opposite side ; both acting, draw head back. The rhomboidei are special antagonists of the serratus mag- nus ; they elevate the superior angle of the scapula and counteract the rota- tion of the trapezius; combined with the trapezius, the scapula is raised without rotation or drawn back and in. Teres major, fixed at humerus, rotates scapula; fixed at scapula, rotates raised humerus in and depresses arm. Latissimns dorsi, fixed at humerus, draws body forward as in using crutches or climbing, feebly in forced respiration ; fixed below, carries ele- vated arm down, back, and rotates in ; draws shoulder down and back ; is used in swimming; keeps inferior angle of scapula close to chest-wall. Serratus post, sup., muscle of forced inspiration ; serratus post, inf., muscle of forced expiration (Quain says of inspiration, as it holds the lower ribs fixed when the diaphragm tends to draw them up). Splenii of one side draw head and neck back and rotate face to same side ; help keep head erect. What are the dorsal and lumbar fasciae ? The vertebral aponeurosis represents the middle portion of the muscu- lar sheet of the serrati ; above, it passes beneath the superior serratus ; below, it is blended with the lat. dorsi and inferior serratus, and binds down the long extensor muscles. The lumbar aponeurosis is usually described in three layers, enclosing the erector spinae and quad, lumbo- rum: its posterior layer is continuous with the vertebral aponeurosis, and by it the lat. dorsi and inferior serratus are attached to the vertebral spines. (h) Deep Longitudinal ^ Muscles.— Lo^G Muscles. — 1. M. Sacro- spinalis, p. n.* (erector spinas). — Origin, lowest two or three dorsal, all the lumbar and sacral spines, posterior fifth of inner lip of iliac crest, lower and back part of sacrum, anterior surface of lumbar fascia : oppo- site the last rib this mass divides into middle and outer columns, and an inner one, spinalis dorsi, separates from the middle in the upper dorsal region. The outer and middle portions subdivide. Middle. Portion. Outer Portion. Longissimus dorsi (Longissimus Sacro-lumbalis (Ilio-costalis lum- dorsi, p. w.). ^^ ^ ^ borum, _p. ?!.). Transversalis^ cervicis (Longissi- Accessorius (Ilio-costalis dorsi, p. mus cervicis, p. 71.). ^ ^ n.). ^ Trachelo-mastoid (Longissimus Cervicalis ascendens (Ilio-costahs capitis, p. n.). cervicis, p. ?i. ). M. ilio-costalis lumhorum (sacro-lumbalis), from outer and superficial portion of common mass into angles of lower six or seven ribs. 31. ilio-costalis dorsi ( acce.ssor ius ), /rom ribs into which the preceding is inserted, but internal to it, into angles of the upper six ribs and trans, proc. of the seventh cerv. vert. * A commission of anatomical nomenclature has suggested for universal use names here marked p. n. (proposed name). It is practically the nomenclature of Henle. MUSCLES AND FASCIA OF THE BACK. 143 M. ilio-costalis cervicis (cervicalis ascendens) continues the series from angles of upper four or five ribs into posterior tubercles of fourth, fifth, and sixth cerv. trans, proc. M. longissimus dorsi rises from common mass, has two sets of inser- tions — an inner row of round tendons into all the dorsal trans, proc. and lumbar accessory proc. ; an outer row to the lowest nine or ten ribs be- tween angles and tuberosities, and to whole length of lumbar trans, proc. and into lumbar fascia. M. longissimus cervicis (transversalis cerv.), from highest four or five dorsal trans, proc. into posterior tubercles of trans, proc. of five cerv. vert. , second to sixth inclusive. M. longissimus capitis (trachelo-mastoid), by four tendons from the upper dorsal trans, proc. , and from articular proc. of the lower three or four cervical vert., into the posterior margin of the mastoid process under the splenius cap. and sterno-mastoid. It shows a tendinous inter- section near its insertion : it is the only muscle between the splenius and complexus. 2. Musculi spinales, spinous muscles, have an arched direction. (1) M. spinalis dorsi, close inside the longissimus dorsi and connected with it ; origin, lowest two or three dorsal spines and from tendons passing from upper lumbar spines to long, dorsi ; inserted by four to nine slips into the upper dorsal spines. (2) M. spinalis cervich, inconstant or difi*erent on the two sides /rom lig. nuchas and seventh cerv. spine, and one or two above or below this ; inserted into spine of axis or also into third and fourth cervical spines. M. sacro-coccygeus posticus, or extensor coccygis (rare), from lower end of sacrum to coccyx, represents a strong extensor of lower animals. 3. M. transverso-spinalis, a common name for a group all inclined in- ward from transverse to spinous processes. [a) Mm. Seftnispinales (half-spinous). — (1) M. semispinalis dorsi, hy five or six tendons from the trans, proc. of the dorsal vert. , from the sixth to the tenth, inclusive ; inserted by just as many tendons into the spines of the upper four dorsal and lower two cervical vert. (2) M. semi- spinalis ca^vicis, covered by the complexus, rises nearly from the inser- tion vertebrae of preceding — viz. upper five or six dorsal trans, proc. ; inserted into cervical spines from second to fifth, inclusive, being thickest into the axis. (3) M. semispinalis capitis (complexus) rises by two sets of heads : the inner, or hiventer cervicis, rises from three or four dorsal trans, proc. between the second and sixth ; its superficial fibres are in- serted into the external occipital protuberance beside the lig. nuchas ; its deeper fibres join the external head. The outer head iv'ses from upper dorsal and lower three or four cervical vert., on the dorsal and seventh cerv. from trans, proc, on the remaining cerv. vert, (fourth, fifth, or sixth) by two slips from each, one from the posterior tubercle of the trans, proc, and one from the lower articular process. These fibres unite, join part of the inner head, and are inserted into the inner im- 144 MUSCLES OF THE TRUNK. pression between the two curved occipital lines. A tendinous inscrip- tion crosses the muscle near the spine of the axis ; another crosses the biventer lower down. (b) M. multifidus (spinas) occupies the groove beside the spinous pro- cesses from the sacrum to the axis; rises from deep surface of erector spinge, from back of sacrum as low as fourth foramen, posterior extrem- ity of ilium, and posterior sacro-iliac ligament ; in lumbar region from mammillary processes; in dorsal, from trans, proc; in cervical, from ar- ticular processes of the four lower vert. The bundles pass up and in, to be inserted into the whole length of the spines from the last lumbar to the axis : some fibres go to the fourth vertebra above, others to those nearer. (c) Mm. Rotator es. — (1) Mm. rotator es longi^ really a part of the mul- tifidus, only in dorsal region, from upper edge of a trans, proc. to lateral edge of root of the second or third spinous process above. (2) Mm. rotatores breves (rotatores dorsi of Quain), eleven in number, dorsal region, nearly horizontal, from upper edge of a trans, proc. to lower edge of the lamina above. Short Muscles. — All those connecting adjacent vertebrae. 1. Of Flexion-vertebrce. — 1. Mm. inter spinales, vertical sets of fibres in pairs between contiguous spinous processes ;^ in the neck they are round, in the back are usually absent, in the loins are flat from side to side. 2. Mm. Intertransversales (posterior, as there is also an anterior set in the neck). — In the lumbar region there are two parts — an inner, inter- transversalis post, medialis, from a mammillary process to an accessory or mammillary process next above ; an external, intertr.post. lateralis^ between two contiguous trans, proc. In the back the inner portion is supplied by the intertransverse ligaments, the outer portion by the lev. costarum ; in the neck and upper dorsal region they are single bands be- tween the trans, proc. and behind the cervical nerves. 3. Mm. levatores costarum^ twelve on either side, i^se from the tips of the trans, proc. of the seventh cervical and upper eleven dorsal vert. ; continued externally into the external intercostals, and inserted into the outer surface of the rib belonging to the vertebra below that from which it springs, between the tuberosity and angle. Those muscles passing to the adjacent rib are lev. cost, breves : in the lower dorsal region are lev. cost, longi,. which pass over one rib. II. Short Muscles of Rotation-vertebrce and Occiput. — Five on each side ; two rise from the axis and three from the atlas. 1. M rectus cap- itis posticus major. — Origin^ spine of axis, upper border; iyisertion^ into and below the middle third of the inferior curved line of the occiput. 2. M. obliquns cap. inferior^ strongest of these muscles. — Origin^ upper and posterior part of arch of axis (Henle) ; insertion, back part of trans, proc. of atlas. 3. M. rectus cap. post, rninor.— Origin, poste- rior tubercle of atlas ; insei'tion, into and beneath inner third of inferior curved line of occiput, covered partly by the major muscle. 4. 31. MUSCLES AND FASCIA OF THE ABDOMEN. 145 ohliqum cap. superior. — Origin^ upper surface of trans, proc. of atlas; insertion., impression between outer parts of the occipital curved lines. 5. M. rectus cap. lateralis. — Origin., anterior surface of apex of trans, proc. of atlas; passes nearly straight up to the jugular process of occiput. The two oblique muscles, with the rect. cap. post, maj., form the suboccipital triangle. Suboccipital muscles may be doubled. M. atlanto-mastoid., from transverse process of atlas to hinder part of mastoid. Nerves. — All the above back muscles by posterior primary branches of spinal n. Actions. — The longitudinal muscles extend the back with a force of 200-400 pounds : some of the lower muscles may depress the ribs and aid in forced expiration ; some of the upper, if fixed above, may act in forced inspiration. The muscles of one side produce lateral flexion of the spinal column. The complexus and transverso-spinalis rotate the head and spine to the opposite side. The rectus minor and superior oblique chiefly extend the head ; the rectus major and inferior oblique rotate the atlas and skull on the axis ; the major also ex- tends the head. The lev. costarum have but little action on the ribs ; are re- garded as muscles of forced inspiration. The rectus lat. bends the head to one side. MUSCLES AND PASCIiE OP THE ABDOMEN. Describe the abdominal muscles and fascise. The superficial fascia of the abdomen has two layers: (1) subcuta- neous^ containing fat ; (2) creeper contains yellow elastic tissue, correspond- ing to tunica abdominalis of animals for support of viscera. From the deeper layer is derived the suspensoi^ ligament of th& penis ; its lower part, fascia of Scarpa, passes over Poupart's ligament and ends just be- low in the fascia lata. Both layers pass over the spermatic cord to the scrotum, become reddish and muscular, forming the dartos. There is no deep fascia. The abdominal muscles fill the space between the chest, lumbar ver- tebrae, and pelvis. (a) Vertical MuscJes. — 1. M. rectus abdominis, separated from its fel- low by the Hnea alba. — Origin., cartilages of fifth, sixth, and seventh ribs, and usually bone of fifth, by three slips, sometimes from the ensi- form ; insertion, by two tendons, the inner smaller one into the front of the symphysis pubis, crossing its fellow of the opposite side, passing down and out to adductor fascia, down and in to fascia of penis ; the outer head into the pubic crest or space in front of it if the pyramidalis is lacking. (Henle considers the insertion as below, as it passes into so much mov- able fascia. ) The fibres are interrupted by zigzag tendinous inscriptions, the three naost constant being one at the umbilicus, one at the lower end of the ensiform,^ and one between these two : if one or two more are added, they are incomplete and below the umbilicus. They do not pen- etrate the whole thickness of the muscle ; may extend into the internal 10— A, 146 MUSCLES OF THE TRUNK. oblique ; are not vestiges of ribs, but of the septa between the original vertebral myotomes. Jf. rectus lateralis ahd., 1 inch (2.5 cm.) broad, between the external and internal oblique muscles, from the tenth rib down over the eleventh to the middle of the iliac crest. 2. M. pyramidalis rests on lower part of rectus inside its sheath, separated from it by a special fascia. Origin^ front of pubis below in- sertion of outer tendon of rectus, passes over the lower third of the space between the umbilicus and pubis ; inserted into the linea alba. Its inner fibres are vertical, outer ones oblique. The height of the muscle is variable, unlike on both sides, one lacking ; both lacking in every fourth case ; doubled on one or both sides. When lack- ing the lower part of the rectus is increased in size. The linea alba is a fibrous structure from the ensiform to the pubis, formed by the union of the oblique and transverse aponeuroses, broadest above, \ inch (4-7 mm.), and a little below its middle is the cicatrix of the umbilicus. At the lower end it passes in front of the recti, and here is detached posteriorly a band of longitudinal ^xq^=: adiminicidiim lineoe albce^ spreading out triangularly behind the outer heads of the recti. The linea semilunaris is a^ narrow part of the internal oblique aponeurosis just before it divides into two layers. Linece transvei^sce correspond to the intersections of the rectus. (6) Transverse Muscles. — 1. M. obliguus externus^ or descending oblique, muscular on the side, aponeurotic in front. — Origin., outer surfaces and lower borders of the lower eight ribs (seven, Henle) by slips in a serrated series, five interdigitating with the serratus magnus, the lower three with the lat. dorsi, from lumbo-dorsal aponeurosis connected with first lumb. vert. The slip from the eighth rib is broadest, the others diminish above and below that ; upper and lower digitations rise from near the costal cartilages, the intermediate ones at some distance from them. The fibres from the last two ribs pass nearly vertically down to the anterior half of the outer lip of the iliac crest ; all the rest incline down and forward to the aponeurosis. This is wider below than above, meets its fellow in the linea alba, is connected with the costo-xiphoid ligament, gives origin to the lowest fibres of the pect. major, or is covered by a fascia derived from it ; below it extends from the anterior superior spine of the ilium to the spine of the pubis as a thickened border called Poupart.s ligament. The aponeurosis is perforated by a large opening near the pubis for the spermatic cord in the male and round ligament in the female : this is the external abdominal ring (annulus inguinalis cutaneus, p. 7i.). It is oval or elliptical, 1 inch long, J inch wide in the male, with its base at the pubic crest; its sides are the pillars (crus superius and crus inferius, p. 71.) ; the U2^per or inner is flat and straight, attached to the anterior surface of the pubis, decussating with its fellow or passing to adductor MUSCLES AND FASCIA OF THE ABDOMEN. 147 fascia and dorsum of penis ; the lower or external is thin above, and below is formed by the inner end of Poupart's Hg., attached to the spine of the pubis. The deepest fibres of Poupart's Hg. are sent back to the inner part of the ilio-pectineal line for f inch, forming a layer called Gimhernat's liga- ment^ presenting upper and lower surfaces and a concave margin toward the femoral ring and vein. Some of the fibres of Gimbernat's lig. or of the outer pillar are reflected up and in, under the spermatic cord, behind the inner pillar, in front of the conjoined tendon, covering the posterior wall of the external ring, and pass to the sheath of the rectus and linea alba or interlace with its opposite : this is the reflected Gimhernaf s liga- ment or triangular ligament of Colles. Transverse fibres bind together the oblique fibres of the aponeurosis, and where they cross the ring they are called inter columnar fibres. From them a thin membrane is prolonged upon the spermatic cord, known as the intercolumnar or spermatic fascia. • Generally the ext. oblique and lat. dorsi leave a triangular space be- tween them on the iliac crest, forming Petit' s triangle, where thirty or forty cases of lumbar hernia have been recorded. The external inguinal ligament of Henle (lig. inguinale ext.) is a strengthening band of fascia along the outer part of Poupart's Hg. It springs from the anterior superior spine by two flat roots which form a short canal for the external cutaneous nerve : it runs transversely, and is fused with the iliac fascia at the lower edge of the ext. obi. aponeurosis as far as the crural arch ; there it passes over the femoral vessels and is lost. It receives fibres from the ext. obi. aponeurosis, and sends fibres down to the fascia lata over the sartorius, so that a sagittal section of the ligament and connected fasciae is in the form of a St. Andrew's cross. The superficial fascia, and with it the skin, are attached to the lig. ing. ext., and form the inguinal sulcus (fold of groin). Internally this liga- ment gives ofl' the intercolumnar fibres, and may end in them or in the ext. obi. apon. or in the lig. ing. int. 2. M. Obliquus Internum. — Origin, outer half of Poupart's lig., ante- rior two-thirds of middle ridge of iliac crest, from lumbar fascia ; inser- tion, lower margins of cartilages of last three ribs, its aponeurosis, and by conjoined tendon (with transversalis) arching over the inguinal canal to the front of the pubis and inner part of ilio-pect. line behind Gim- bernat's lig. The aponeurosis splits at the outer border of the rectus ; the anterior layer unites with the ext. obi. apon., the posterior with the transversalis apon., which reunite and form the sheath of the rectus; the posterior layer is attached above to the ensiform, seventh and eighth rib-cartilages. This division of aponeurosis stops a little above halfway between the umbilicus and pubis, and below this point the int. obi. apon. and transversalis apon. pass wholly in front of the rectus. This de- ficiency in the posterior wall of the sheath is marked by a lunated edge, concave downward, the semilunar fold of Douglas (linea Douglasii, p, 71. ) ; here the rectus is separated from the abdominal contents by 148 MUSCLES OF THE TRUNK. peritoneum, subperitoneal tissue, transversalis fascia, and a thin con- nective tissue which continues the trans, apon. (Note a difference between trans, fascia and apon.) Int. obi. muscle may present a fibrous inscription or cartilaginous slip op- posite the tenth or eleventh rib ; fold of Douglas is often indistinct, may be lacking. The cremaster muscle, peculiar to the male, is attached externally to the inner portion of Poupart's lig., and is continuous with the int. obi. fibres : its internal attachment (inconstant) is the spine and crest of the pubis ; it descends in folds in front of the spermatic cord to the level of the testis, and spreads out in a cremasteric fascia. Some regard this muscle as a part of a foetal structure called guhernaculum testis. There are some remains of it in the female. 3. M. Transversalis Abdominis. — Origin^ inner surface of the lower six rib-cartilages, interdigitating with the diaphragm, from lumbar trans, proc. by a posterior aponeurosis, from anterior three-fourths of inner mar- gin of iliac crest, outer third of Poupart's lig. This muscle nearly sur- rounds the abdomen, and is inserted into the anterior aponeurosis and conjoined tendon. This apon. commences for the most part about 1 inch from the outer border of the rectus in the linea Spigelii (p. n.), but muscular fibres nearly meet behind the rectus above : the lower third of this apon. passes in front of the rectus. The posterior aponeurosis is the middle layer of the lumbar fascia or lumbo-costal lig. (Henle), between the erector spinae and quad. lumb. muscles. The highest part of this muscle is continuous with the triang. sterni. Muscle may be absent ; m. puho transversalis behind conjoined tendon from ilio-pectineal line to trans, fascia or aponeurosis. Nerves. — Supplied in general by lower intercostal n. ; int. obi. and trans- versalis also by ilio-hypogastric and ilio-inguinal n. ; cremaster by genital branch of genito-crural n. Actions. — Upon thorax, viscera, or vertebral column ; pelvis and thorax fixed, they aid vomiting, expulsion of foetus, fseces, and urine; vertebral col. fixed, they raise diaphragm by pressing up viscera, and so aid expiration; flex thorax to front or laterally, or rotate it if vert. col. be not fixed ; thorax fixed, draw up pelvis in climbing. Pyramidales make linea alba tense. LINING FASCIiE OF THE ABDOMEN. The transversalis fascia covers the inner surface of that muscle, and is continued upon the under surface of the diaphragm : along the inner margin of the iliac crest it is attached to periosteum ; for about 2 inches internal to the ant. sup. iliac spine it is attached to the back of Poupart's lig. and iliac fascia ; next internally it passes down over the femoral ves- sels as the anterior portion of their sheath : as it passes under Poupart's lig. it is strengthened by the deep crural arch (arcus cruralis), a band of fibres inserted into the pubic spine and ilio-pectineal line behind the con- LINING FASCIA OF THE ABDOMEN. 149 joined tendon : it includes beneath it, between the femoral vein and Gimbernat's lig., the femoral ring, through which a femoral hernia may descend. Halfway between the ant. sup. iliac spine and symphysis pubis is the internal abdominal ring (annulus inguinalis abdominalis, p. n. ) : its lower edge is vertically J inch (8 mm.) above Poupart's lig. and IJ inches (4 to 5 cm. ) from the outer ring. From the inner end of the ilio-pectineal line fibres of transversalis fascia go in two directions — outward, beneath the internal ring and parallel with Poupart's lig., the lig. inguinale int. laterale; upward, on the inner side of the ring as the lig. ing. int. mediale (outer and inner parts of internal inguinal ligament). These two form a blunt angle, limiting the internal ring below and internally. From the margin of the ring is prolonged the delicate infundihuliform fascia (processus vaginalis fasciae trans. ) The ring is the entrance into this process, the lower sharp border of which is the plica semilunaris fascice trans, (fre- quently lacking). In the region of the umbilicus are strengthening fibres covering the obliterated umbilical vein ^= fascia transversalis umhilicalis. The iliac fascia covers the ilio-psoas muscle, stretched from the iliac crest to the ihac portion of the ilio-pect. line : it is continued up on the psoas, attached to the sacrum, in vertebral disks, internal arched ligament of diaphragm, and externally to ilio-lumbar ligament (ant. layer of lumbar fascia). Below it passes beneath the femoral vessels, forming the hinder part of the femoral sheath : outside the vessels it unites with the trans- versalis fascia on Poupart's ligament and with the ext. ing. Hg., which prolongs it to the fascia lata (ihac portion) ; internally it joins the pubic portion of the fascia lata. A strong band is att,ached to the ilio-pect. eminence between the psoas and pectineus, called the ilio-pect. lig. Describe the fasciae of the perineum and pelvis. Fasdce of Perineum, Superficial. — In the anterior half of the peri- neum, continuous with the dartos, is the superficial perineal fascia, or fascia of Colics, bound to the ischio-pubic rami as far back as the ischial tuberosities : on a line from this tuberosity to the central point of the perineum it turns round the transversus perinei muscle and becomes deep perineal fascia. There is an incomplete median septum, so that extravasated urine distends one side of the scrotum beneath the dartos, then penetrates to the other side, then to the front of the abdomen be- neath the superficial fascia, but does not pass to the posterior half of the perineum nor down upon the thighs. BucFs fascia is the continuation forward of Colles' fascia, investing the penis as far as the glans, contin- uous with the dartos, and directing the urine as already stated. The deep perineal or subpubic fascia or triangular ligament of the urethra is stretched across the subpubic arch on the deep surface of the crura and bulb, and consists of two layers : the inferior layer extends back to the central point of the perineum, attached to the ischio-pubic 150 MUSCLES OF THE TRUNK. rami, connected at its base with the other layer, and continuous with the recurved margin of the superficial perineal fascia. The transverse lig. of the pelvis is connected with this layer, and meeting from below the arcuate pubic lig. (subpubic) forms an aperture for the dorsal vein of the penis. This layer is perforated by the urethra, arteries of the bulb and of the corpora cavernosa. Between the two layers of the triangular ligament are the membranous portion of the urethra, the constrictor urethrae, Cowper's glands, pudic vessels, and dorsal nerves of penis. T\iQ superior (deep) layer consists of right and left lateral halves, sepa- rated in the middle line by the urethra close to the prostate, and con- tinuous on each side with the fascia covering the obt. int. muscle. The levator ani is between this layer and the recto-vesical fascia. FasdoR of the Pelvis. — This consists of two parts, obturator and recto- vesical fascia. The obturator fascia covers the inner surface of the obturator internus muscle ; it is attached to the iliac portion of the ilio-pect. line, to the body of the pubis, to the great sacro-sciatic notch and great sacro-sci- atic ligament, and upper edge of obturator membrane ; below it joins the falciform process of the great sacro-sciatic ligament and bounds the ischio-rectal fossa externally. Near its upper margin it gives off the anal fa^cia^ which covers the lev. ani externally and bounds the ischio- rectal fossa internally. The fascia of the pyriformis is continued back from the obturator in front of the pyriformis muscle and sacral plexus. The recto-vesical fascia is attached in front to the back of the pubis, and laterally separates from the obturator fascia along a curved line from the upper part of the obturator foramen to the ischial spine : this is the posterior part of the. white line which extends from the pubis to the ischial spine. This fascia, covering the upper surface of the lev. ani muscle, passes to the prostate gland, bladder, rectum, and from side to side across the median line. The part to the prostate and neck of blad- der from the pubis consists largely of involuntary muscular fibres, the anterior true ligaments of the bladder^ or pubo-prostatic ligaments; out- side them are the lateral true ligaments^ and the part going to the rec- tum is the lig. of the rectum. The anterior part of the fascia meets the bladder along its junction with the prostate, and divides into two layers : the upper (ascending) unites with the muscular coat of the bladder, and is attached just outside the vesiculse seminales ; the inferior layer (de- scending) forms the sheath of the prostate, and at its apex is continued into the upper layer of the triangular ligament ; it also passes between the bladder and rectum and forms the front of the sheath of the latter. The vagina receives the recto-vesical fascia in a manner similar to the prostate. Describe the muscles of the perineum. Two groups— anal and genito-urinary, with a superficial and deep set in each. MUSCLES OF THE PERINEUM. 151 A. In the Male. — (a) Anal Muscles, — ^The internal or circular sphinc- ter is a thick ring of unstriped muscle continuous with the circular fibres of the rectum. The external sphincter^ 1 inch in depth, is elliptical, attached by a small tendon to tlie coccyx, encloses the anus, and superficial fibres end in skin ; some decussate across the median line ; a few deep ones are continuous from side to side, but a large part blend with the muscles at the ' ' central point. ' ' The cmtral point of the perineum is the median part of a tendinous septum in which several muscles meet : it is 1 inch in front of the anus, behind the bulb of the urethra ; may be absent. The levator ani rises from the pubic body, adherent to and between the obt. and recto-vesical fasciae, from the "white line," spine of the ischium, and upper layer of triangular ligament. The hinder fibres pass down and in to the coccyx. The foremost run almost directly back to the "central point," the intervening ones to the lower end of the rec- tum and median aponeurosis between coccyx and anus, common to the two muscles. This muscle is divided by a cleft just below the obturator canal into two parts: the anterior pubo-coccygeus (Savage) is alone connected with the rec- tum ; its outer fibres pass over the side of the prostate, continue the ext. sphincter upward, unite with its fellow behind the bowel, and are inserted into the coccyx; the inner fibres pass between the two sphincters and join the longitudinal fibres of the rectum and decussate in front of the anus. The hinder part of the muscle, iscMo-coccygeus (Henle), passes from the pelvic fascia and ischial spine to the margin of the coccyx and median aponeurosis. The coccygeus, or levator coccygeus^ rises by its apex from the ischial spine and obturator fascia, and is inserted by its base into the margin of the coccyx and lower part of the sacrum. This with the above muscle, on both sides, constitute the pelvic diaphragm, M. sacrO'Coccygeus anticus, curvator coccygis, from anterior surface of sacrum to anterior surface of coccyx. (h) Genito-iirinai^ Muscles. — Three on each side and a central deep one. Transversus Perind. — Origin., ischial tuberosity passes forward and inward to unite with its fellow, the external sphincter, and bulbo-cavern- osus at the "central point." Very variable, inconstant insertion, absent, composed of several slips. M. gluteo-perinealis from glut. max. to this muscle. Ischio-cavernosu,% or Erector Penis. — Origin^ inner part of tuberosity and ramus of ischium, behind and on each side of the attachment of crus penis : its tendon spreads over the crus, and is inserted into the outer and under sides of that body at its fore part. 152 MUSCLES OF THE TRUNK. Houston describes the m. compressor' vense dorsalis penis, rising in front of the crus and erector penis, and joining its fellow above dorsal vein ; it is well de- veloped in the dog. Bulbo-cavernosus, or ejacidator urhice.^ unites with its fellow in a median raphe continued forward from the ' ' central point, ' ' the two covering the bulb and part of the corpus spongiosum. Its fibres ascend from the raphe and end on the dorsum of the corpus spong. by joining its fellow ; at the fore part some pass to the outer side of the corpus cavernosum and send an expansion over -the dorsal vessels ; some of the posterior fibres unite with the under surface of the triangular ligament. The fibres surrounding the bulb are somewhat distinct from the rest, and have been described as the m. compressor hemispliserum bulbi. The above three muscles and enclosed triangular space are between the superficial and deep perineal fasciae — i. e. below the lower layer of the triangular ligament. The constrictor or compressor urefhroe rises from the ischio-pubic rami, from the two layers of the triangular ligament, between which it is placed, and surrounds the membranous portion of the urethra, forming a kind of sphincter. A median raphe sometimes divides the muscle. Its hindermost fibres have been described as the trans, permei profundus. Most of the fibres pass transversely, others obliquely, others circularly around the urethra, and on the inferior surface is a longitudinal slip from the base to the apex of the triangular ligament. Nerves. — External sphincter by fourth sacral and inf. hemorrhoidal of pudic ; lev. ani by fourth sacral and perineal branch of pudic ; coccygeus by fourth sacral ; the three superficial gen. -urinary muscles by the perineal branch of the pudic ; constrictor urethrse by dorsal nerve of penis. Actions. — Int. sphincter wholly involuntary, external usually involuntary, but made firmer by act of will ; lev. ani and coccygeus support and raise floor of pelvis, and thus have to do with forced expiration ; the levator also assists in emptying the lower rectum, raising and expanding its "aperture, but some of its fibres act with the ext. sphincter in closing the anus ; the transversi fix the "central point " and give support to the ejaculator muscles ; the ischio- cavernosi compress the crus and help produce and maintain the erection of the penis ; the bulbo-cavernosi forcibly eject fluid mostly voluntarily at the end of micturition, involuntarily in the emission of semen ; they also are supposed to aid erection of penis ; the constrictor urethrx assists the bulbo-cavernosi in clearing the urethra and erects penis (Henle). B. In the female^ the transversus perinei^ ext. sphincter., lev. ani., erec- tor clitoridis (ischio-cavernosus) correspond to similar muscles of the male, the sphincter vagince to the bulbo-cavernosi. The constrictor ure- thrce is the trans, perinei profundus, and differs from that of the male by being divided into lateral halves by the vagina. Describe the diaphragm or midriff. A partition between the abdomen and thorax, rising by muscular fibres as vertebral^ costal^ and sternal portions. THE DIAPHRAGM. 153 The crura^ or pillars of the vertebral portion, connected with the ant. common lig. , rise from the bodies and intervertebral subs, of the lumbar vertebrae, the right from the second, third, and fourth, the left from the second and third ; they arch over the aorta from right to left, and meet behind it from left to right. The muscular fibres from them form a figure 8, leaving an opening for the oesophagus. The internal arched ligament passes over the psoas muscle from the outer side of the first lumbar body to the second trans, proc. The external arched ligament passes over the quad, lumborum from the second trans, proc. to the last rib ; they are the upper margins of fascia covering those muscles ; an arched ligament may pass over both muscles ; muscular fibres of the diaphragm rise from both. The costal portion rises from the lower six cartilages, interdigitating with the transversalis abd. The sternal portion is very short — a single muscular slip, sometimes two, from the ensiform cartilage. , The central tendon^ trefoil, forms the highest part, convex in front, concave behind ; has three lobes, the right being the largest, the left the smallest ; the tendinous fibres are interwoven in every direction. There are three foramina. : the hiatus aorticns, in front of the first lumbar, transmitting the aorta, thoracic duct, and yena azygos mag. ; the foramen for the oesophagus^ opposite tenth dorsal vert., entirely sur- rounded by muscle, oval, transmits oesophagus, pneumogastric nerves, and branches of the coronary artery ; the foramen quadratum for vena cava is in the highest part of the central tendon, at level of disk between the eighth and ninth dorsal vert. ; its sides are firmly attached to the vein. A sterno-diaphragmatic hgament passes to this foramen. Small foramina are in the crura for splanchnics on both sides, for small azygos vein on left side : the sympathetic cord perforates the crus or passes under the internal arched ligament. There are four weak places .* ( 1 ) between costal and vertebral portions near quad. lumb. ; (2) between costal and sternal portions = Larrey's spaces; (3) oesophageal opening; (4) where sympathetic cords pierce crura. Left side, as a whole, is the weaker: at Larrey's space is peri- toneum below, then areolar tissue, then pericardium on left side and pleura on right side. Highest point of diaphragm on right side in dead body is level of fifth rib-cartilage with sternum; on left side of sixth cartilage with sternum (Quain) ; mid-portion is flat, supports the heart, and is nearly immovable. A considerable extent of origin of diaphragm is in contact with the thoracic wall. Relations are, above, pleurse and pericardium, lungs, and heart; below, peritoneum, liver, stomach, pancreas, spleen, and kidneys. Nerves. — Phrenics, lower intercostals, and sympathetic. Actions. — By its contraction and descent the viscera are pushed down and thorax lengthened ; it elevates the ribs when its vault is supported by the abdominal viscera : its anterior fibres oppose forward movement of the sternum. 154 MUSCLES OF THE TRUNK. MUSCLES AND FASCIA OF THE BREAST. Describe the breast muscles and fasciae. IJascia of Pectoral Region. — Superficial contains the mammary gland, sending septa into it and supporting it. The deep fascia is thin : a part of it is the costo-coracoid membrane behind the pect. major ; this en- sheathes the subclavius, and its posterior layer blends with the sheath of the axillary vessels. The anterior layer from the coracoid to the first rib may be called the costo-coracoid ligament : it is prolonged down, in- vests the pect. minor, and merges into the axillary fascia at the border of the pect. major.^ The axillary fascia stretches between the two folds of the axilla, and is continuous with the sheath of the vessels and apo- neurosis of arm. a. Superficial Breast-muscles. These muscles converge to their insertion into the upper extremity and its girdle : the deep ones belong to the bones of the trunk, and are in three layers like the transverse ones of the abdominal wall. First Layer. — M. pectoralis major, two portions, clavicular and sterno-costal ; the clavicular portion rises from the inner half of the anterior surface of the clavicle and sterno-clavicular capsule, the sterno- costal from the sternum (superficial part, Henle), and upper six rib- cartilages (deep part, Henle) and from anterior sheath of rectus and ext. obi. apon. The fibres converge to be inserted by two tendons, united along the lower margin, into the external bicipital ridge : the clavicular and upper sterno-costal parts form one tendon with straight fibres : the lower sterno-costal part twists so that its lowest fibres are inserted highest up ; a bursa separates this from the other anterior tendon. This poste- rior layer also gives ofi" three expansions — one over the biceps tendon to the capsule of the shoulder-joint, one lining the bicipital groove, and one to the fascia of the arm. Variable in extent of origin and separation of heads. M. chondro-epitro- chlearis, from one or two rib-cartilages below pect. maj., or from it or from ext. obi. apon. to fascia of arm, internal intermuscular septum, or inner epi- condyle. M. sternalis brutorum lies on pect. maj. parallel to sternum; passes from sheath of rectus or third to seventh cartilages to sterno-mastoid, to upper cartilages, to sternum or pect. maj. If two are present, they may unite across the manubrium. Second Layer. — L M. subclavius rises from the groove on the under surface of the clavicle and recess between the conoid and trapezoid liga- ments ; inserted into junction of first rib with its cartilage between fibres of costo-clavicular ligament. May be attached to coracoid, and not to clavicle, or to both, or to scapula, as m. sterno-scapularis ; m. sterno-claviciilaris anticus from manubrium : if both are present, a digastric interclavicular muscle may connect them across the manu- brium. Another variety of this is m. supraclavicular is, from upper edge of manubrium, either anteriorly or posteriorly, behind sterno-mastoid to upper MUSCLES AND FASCIA OF THE BREAST. 155 surface of clavicle (1 in 20). There may be the scapulo-clavicularis or coraco- clavicularis. 2. M. pectorah's minor from three ribs near their cartilages, usually third, fourth, and fifth, often second, third, and fourth or fifth, and from intercostal aponeuroses; insertion^ inner border and upper surface of coracoid ; a bursa is under its insertion (1 in 40 cases). Each costal origin may remain separate in the muscle : its insertion may be continued into the capsule and great tuberosity ; the insertion is represented normally by the coraco-humeral ligament. Absence of whole muscle. M. pectoralis minimus (rare), from first costal cartilage to coracoid. Third Layer. — M. serratus anticus^ p. n. (serratus magnus), placed between ribs and scapula. Origin^ first eight or nine ribs by as many slips : the first slip is attached to two ribs ; insertion., posterior border of scapula and into the flat surfaces at upper and lower angles, not in the subscapular fossa. There are three sets of fibres: (1) first digita- tion, from first and second ribs, passes up to flat area at upper angle ; (2) second and third digitations, from second and third ribs, pass down in a thin triangular layer to the whole line between the upper and lower angles; (3) the remaining five or six digitations converge, some up and some down, to the flat surface in front of the lower angle. Varieties. — Slip from tenth rib ; lower digitations or slip from first rib ab- sent ; may be united with levator scapulae, as is the case in many mammals. May be a bursa at the upper angle of scapula or between the serratus and chest- wall. Nerves. — The pectoralis major by the two anterior thoracics ; the minor by the int. ant. thoracic n. ; the subclavius by the fifth and sixth cervical ; ser- ratus anticus by the posterior thoracic, upper division by fifth c, middle by sixth c. (often fifth c. also), lower by sixth and seventh c. Actions. — Pect. major. Arm at Side, Arm Abducted to 90°. Arm Raised High. First part of muscle Draws arm forward Draws arm forward to draws arm up and and rotates in. horizontal, and no far- in. ther. Second part of muscle Draws arm down, in, Adducts, draws down. draws arm down and and rotates in. rotates in. It assists the lat. dorsi in adduction, opposes it in flexion; lowest fibres are best adductors ; succeeding ones draw forward ; used in swimming. Fixed above the pectorales, draw body forward; the major does not draw up the ribs, the minor does not seem to, so that they have no inspiratory action. The subclavius depresses clavicle or steadies it ; may act in inspiration ; sup- ports sterno-clavicular joint. The pect. minor draw-s coracoid down and for- ward, depresses shoulder, throws lower angle of scapula backward, acts with levator and rhomboidei in rotating scapula. The scapula is slung by the ser- ratus magnus and rljomboidei, is kept in equilibrium by them ; lower portion of serratus, combined with trapezius, rotates scapula on an axis near its supe- 156 MUSCLES OF THE TRUNK. rior angle and elevates shoulder; upper fibres bring scapula forward and down, assisted by pect. minor ; whole muscle brings scapula forward, acts in all movements of pushing, keeps scapula pressed to ribs ; of no importance in respiration ; middle fibres only might pull ribs down. h. Deep Breast-muscles. First Layer. — Mm. intercostales externi, thicker behind than in front, are directed obliquely downward and forward between the borders of two ribs : they extend from the tuberosities to the outer ends of the cartilages, not quite reaching them above, but continued along their bor- ders in the lower two spaces. They are continued to the sternum as anterior intercostal aponeuroses or ligg. intercostalia ext. M. supracostalis from anterior end of first rib, from cervical fascia or scaleni to fourth or to second and third ribs. Second Layer. — Mm. inteixostdles interni, thicker in front, incline down and back, but less obliquely than the external set ; are attached to the inner surfaces of two ribs. Anteriorly they reach the sternum, and the last two are continuous with the int. obi. muscle ; posteriorly they fo to the angles or a little beyond. Their deficiency behind is supplied y the post, mtercost apon.^ which merge on one side into the ant. cost, -trans, lig. , and on the other into a thin fascia between the muscles. Third Layer. — Mtu. Transversi Thoracis. — 1. M. trans, thoracis posterior (subcostal muscles) are small slips on inner aspect of thorax, connected with int. intercostals near angles of ribs ; run in same direc- tion as int. intercost. , and extend over one or two spaces ; origins^ reach from twelfth rib to third ; insertions^ from tenth to second. 2. M. Transversus Thoracis Ant. (triangularis sterni). — Muscular and tendinous fibres behind the costal cartilages rise from ensiform, lower part of sternum, and cart, of lower two or three true ribs ; fibres pass up and out ; lowest are horizontal, middle oblique, and upper ones nearly vertical ; inserted to inner surfaces and lower borders of sixth to second costal cartilages, inclusive. It is a continuation upward of the trans, abd. muscle ; may be lacking on one or both sides. Nerves. — All by intercostal n. Actions. — Costal and diaphragmatic respiration are normally combined ; the thorax is increased antero-posteriorly by a forward movement of the sternum, transversely by elevation and eversion of ribs, vertically by descent of dia- phragm ; extension of the vertebral column is also an agent. There are three views as to action of the intercostals : Hamberger's, that the external elevate and internal depress the ribs ; Hutchinson's, that the external and anterior parts of the internal elevate, and the rest of the internal depress ribs ; Hal- ler's is best — that (1) ribs are not joined as by a pivot to vertebral col.; (2) are not parallel bars, but convex arches ; (3) no two ribs can move as they please, being connected above and below, but all move as a system : if fixed point be above, both external and internal intercostals elevate the ribs and are inspiratory muscles ; fixed below, they both depress and assist expiration. MUSCLES AND FASCIA OF THE NECK. 157 Inspiration. Typical Forces. Elasticity of thorax. Diaphragm. Scaleni. Intercostals. Accessory Forces. Sterno-mastoid. Subclavius. Muscles of back of neck. Serratus post. sup. Levatores costarum. Expiration. Typical Forces. Elasticity of thorax. Elasticity of lungs. Weight of thorax and shoulder girdle. Weight of abdomen. Intercostals. Accessory Forces. Quadratus lumborum. Triangularis sterni. Serratus post. inf. Abdominal muscles. Levator ani and coccygeus. MUSCLES AND PASCIiE OF THE NECK. Describe the neck-muscles. Mostly vertical, a superficial or anterior group, some resembling the recti abd. , a deep or posterior group corresponding to the intercostals and serratus anticus. Anterior Neck-muscles. Long Muscles. — 1. Platysma myoides (M. subcutaneus colli) is a pale, thin muscular sheet over the front and side of the neck and lower part of face. Origin., skin and subcutaneous tissue over deltoid, pectoral and trapezius muscles in a line from anterior end of second rib to acro- mion ; fibres pass up and in over clavicle, and are inserted into the lower jaw : the two muscles meet at the hyoid, and the right overlaps the left one ; the posterior fibres blend with the depressor anguli and orbicularis muscles and fasciae. The muscle does not rise from bo'ne ; inserted into bone, muscle, and fascia. A slip to this muscle from the mastoid or occiput ; the m. occipitalis minor from the fascia over the upper end of the trapezius transversely to the fascia over the insertion of the sterno-mastoid (8 out of 25 cases). Platysma repre- sents the panniculus carnosus of mammals, a skin muscle. Nerves. — Inframaxillary branch of facial, but as this unites with the super- ficial cerv. n., it may get some spinal innervation. Action. — Draws angle of mouth down and out ; may depress lower jaw ; being curved, it tends to redress itself, carries skin of neck forward, and is said to be useful in singing by removing pressure from great vessels ; used in swal- lowing and expressing sudden terror ; some say propels saliva from parotid. - Describe the deep cervical fascia (anteriorly). It passes from the trapezius muscle beneath the platysma over the posterior triangle of the neck, invests the sterno-mastoid, and passes over the anterior triangle to the median line. It is attached below to the clavicle, and perforated by the ext. jugular vein ; attached above to 158 MUSCLES OF THE TRUNK. the lower jaw, and becomes the parotid fascia and stylo-maxillary lig. In front it is attached to the hyoid bone, and splits below the thjToid gland : the anterior layer goes to the anterior surface of the sternum, and the posterior, covering the sterno-hj^oid and thyroid muscles, is at- tached to the interclavicular lig. ; between these two layers is the supra- sternal space, extending a short distance on either side behind the sterno- mastoid as the supraclavicular recess. Prolonged from the deeper layer, a fascia invests the posterior belly of the omo-hyoid and holds it down to the first rib, there connected with the costo-coracoid membrane. A pro- cess also passes behind the depressors of the hyoid, invests the thyroid body, passes to the trachea, forms the carotid sheath, and extends to the pericardium. Deepest of all is i\iQ prevertebral fascia. Inside the phar- yngeal muscles is the pharyngeal aj^oneurosis, outside them their proper fascial layer (bucco-pharyngeal), connected to the prevert. fascia by areo- lar tissue, forming the retro-pJiaryngeal space. A prolongation of the prevertebral fascia forms the axillary sheath. Regions of Neck. — Suprah3^oid, submaxillary, submental, infrahyoid, fossa suprasternalis ; on either side the larynx are sulci carotidei, sterno- mastoid region, fossa supraclavicular is minor, above sternal end of clav- icle, fossa supracl. major, between trapezius and sterno-mastoid. 2. M. Sterno-cleido-mastoideus (its full name should mention its inser- tion into the occipital bone). — Origin., sternal head, thick and round, from anterior surface of manubrium ; clavicular , from inner third upper surface of clavicle. The two portions meet, pass up and back to the anterior border and outer surface of mastoid and outer half or more of the superior curved line of the occiput, to meet the trapezius. Spinal access, nerve pierces the under surface of the external portion. Sterno-mastoid and cleido-mastoid parts may remain separate ; the latter will be pierced by the sp. access, nerve. A third factor may be added, cleido- occipital, origin and insertion outside the cleido-mastoid. In animals without a clavicle the cleido-mastoid part is continued into the great pectoral or deltoid. M. supraclavicularis propritis is attached to the clavicle at each end, forming an arch above the middle of the bone. M. levator claviculas, a misplaced part of the sterno-mastoid or scalenus, springs from the middle of the clavicle, and is inserted into the fifth and fourth, fourth and third, or third and second cervical trans, proc. Connected with the insertion of the sterno-mastoid is the M. Trans- versus Nuchce. (18 out of 25 cases). It is covered by the insertion of the trapezius, lies below the superior curved line, concave above, rises from the inner part of this line and ext. occip. protuberance, and is inserted into this line externally and into the sterno-mastoid aponeurosis. When absent it is represented by tendinous fibres. Its purpose seems to be to prolong the sterno-mastoid insertion backward. Nerves.— Both by spinal accessory, offsets of which are joined by the second cervical. MUSCLES AND FASCIJE OF THE NECK. 159 Actions. — The two stern o-mastoids draw the head and neck forward toward the sternum ; one, acting slightly, flexes the head (extends, Henle) and flexes laterally and rotates, so that the face looks up and toward the opposite side. Fixed above, the muscles elevate thorax in forced inspiration. 3. Digastric muscle (m. biventer mandibulae) has two bellies united by a rounded tendon : the posterior belly rises from the digastric fossa of the temporal bone, passes down, in, and forward toward the hyoid bone. The anterior belly is attached close to the symphysis of the lower jaw and directed down, back, and slightly outward : the intervening tendon is attached to the body and great cornu of the hyoid by an aponeurosis and by the stjdo-hyoid muscle, which is pierced by the digastric tendon. The anterior bellies of the two muscles are connected by a dense aponeurosis. Varieties. — Slip from styloid process to post, belly ; slip from near angle of lower jaw to ant. belly ; ant. belly may be split and some fibres cross the median line ; muscle may be monogastric from mastoid to middle of lower jaw; digastric tendon may be in front of or behind the stylo-hyoid. The mento-hyold is a median slip (or two parallel bands) from the hyoid to the chin. Nerves. — Ant. belly by mylohyoid branch of inferior dental from third division of fifth nerve ; post, belly by facial. Actions. — Either an elevator of the hyoid or depressor of lower jaw, accord- ing to which is fixed ; its insertion is not close enough to the hyoid to allow independent action of either belly. Hyoid-hone Muscles, 1. Between Base of Skull and Hyoid. — M. Sfylo-hyoideus. — Origin, by narrow tendon from back of styloid process near its root ; insertion, usually divided for transmission of digastric tendon, and the two portions pass ununited to the hyoid at the junction of the great cornu and body; almost alwa3^s a slip ends in the digastric tendon. May be wanting, may be double; inserted into digastric tendon ; fibres con- tinued to omo-, thyro-, or mylo-hyoid muscles. M. stylo-hyoideus alter, (stylo- chondro-hyoideus or stylo-hy. prof.), from styloid process to small cornu, accom- panying or replacing the stylo-hyoid lig. II. Between Thorax and Hyoid.— First Layer. — 1. M. Stemo- hyoideus. — Origin, back of sternum and sterno-clavicular joint, or from joint and clavicle, from clavicle only, sometimes from first costal carti- lage ; insertion, inner half of lower border of hyoid body. Its inner border approaches its fellow; are far apart below. Transverse intersection at level of omo-hyoid tendon, analogous to rect. abd. ; muscle may be doubled or absent. M. cleido-hyoideus from clavicle to hyoid in front of sterno-hyoid. 2. M. omo-hyoideus, ribbon -shaped, has two bellies and an intermediate tendon. Origin, upper border scapula near notch or from transverse ligament ; passes forward under trapezius across scaleni, beneath sterno- 160 MUSCLES OF THE TRUNK. mastoid, then vertically to lower border of hyoid, partly beneath and partly in front of the sterno-hyoid insertion. Its tendon beneath the sterno-mastoid at level of cricoid cartilage is enclosed in the deep cer- vical fascia, which is prolonged down to the sternum and first costal cartilage, while the fascia investing its posterior belly descends to the clavicle. Varieties. — Frequent, doubled or absent ; clavicle may be sole origin of post, belly (m. deido-hyoideus) ; band of fascia may take the place of its ant. belly ; the post, belly may have an accessory slip to the clavicle, first rib, or cervical fascia (m. coraco-cervicalis), others to the sterno-mastoid, sixth cerv. trans, proc. or fascia of scalenus, M. cervico-costo-humeralis has been seen, from small tuberosity of humerus, inserted by two tendons, one to sixth cerv. trans, proc, one to anterior end of first rib. The omo-hyoid and sterno-hyoid muscles are parts of the same muscular sheet; the fascia binding down the post, belly may contain striped muscular fibres ; the varieties of the muscle come from the different degrees of cleavage of this sheet. Second Layer. — 1. M. sternothyreoideus lies behind the sterno- hyoid, and rises from posterior surface of manubrium internal to the sterno-hyoid, variably from first and second costal cartilages, diverges from its fellow ; inserted into oblique line of thyroid cartilage, covering some fibres of the inf constrictor. Muscles united at origin, absent or doubled; transverse inscriptions; a slip to fascia of neck {costo-fascialis)f or one from the carotid sheath to the outer border of the muscle. 2. M. thyreohyoideus^ a continuation of the preceding from the oblique line of the thjToid cartilage to the outer half of the lower border of the hyoid and anterior half of great cornu. M. hyo-thyroideus lat. from apex of great cornu to apex upper horn of thy- roid cart. M. cricohyoideus between cricoid cart, and hyoid bone. M. transversus colli, in the lower part of the neck, represents the mm. trans, abd. and thoracis : it springs from the upper edge of the first costal cartilage, and passes, fan-shaped, in many fine tendinous fibres between the sterno- hyoid and sterno-thyroid muscles, meeting or crossing its fellow in the middle line: some fibres end in the interclavicular ligament or stern o-clavicular capsule. III. Muscles :Setween Lower Jaw and Hyoid Bone. First Layer. — M. Myhhyoideus. — Origin^ from mylo-hyoid ridge of lower jaw, extending from last molar tooth nearly to symphysis; fibres pass inward, back, and downward, hinder ones to body of hyoid, a larger number into the median raphe between the two muscles, which extends from near the symphysis to the hyoid ; the posterior border is free ; the two muscles form the " diaphragm of the mouth." May be closely connected with or replaced by ant. belly of digastric ; may receive slip from other hyoid muscles ; may be deficient at fore part. Second Layer. — 31. gemohyoideus has a narrow origin from the MUSCLES AND FASCIA OF THE NECK. 161 inf. mental spine ; fibres pass straight back to anterior surface of body of hyoid, and frequently send a small slip to the small cornu over the hyoglossus or another to the great cornu. It may be blended with its fellow or doubled. iVieri;es.— Stylo-hyoid by facial, mylo-hyoid by mylo-byoid branch of inf. dental of third div. of fifth; all the others of this group attached to the hyoid bone apparently by the hypoglossal, but really by the first, second, and third cerv. nerves via the conimunicans and descendens noni (so called). Actions. — Sterno-hyoid and omo-hyoid depress the hyoid bone ; the sterno-thy- roid depresses that cartilage, may make vocal cords tense, but with the thyro- hyoid depresses the hyoid bone ; the latter also draws up the larynx ; may relax vocal cords, and produces descent of epiglottis. These muscles restore the larynx and hyoid after the act of swallowing, and depress them in utter- ance of low tones. The infrahyoid muscles may act in forced inspiration. The mylo-hyoid and genio-Jiyoid elevate the hyoid and draw it forward, or depress the lower jaw, depending upon which is fixed : the former raises the floor of the mouth and forces food back. The stylo-hyoid acts only on the hyoid bone ; aided by the mid. constrictor, it draws it up and back. Describe the extrinsic muscles of the tongue. M. genio-hyoglossus^ fan-shaped, is placed vertically in contact with its fellow. Origin, superior mental tubercle ; lower fibres .pass to body of hyoid and side of pharynx, superior to tip of tongue, and intermediate to whole length of tongue, vsome decussating across the median line. Slips may pass to the epiglottis, stylo-hyoid lig., or small cornu of hyoid bone. M. hyoglossus is flat and quadrate. Origin, whole length of great cornu and lateral part of hyoid body ; insertion, posterior half of tongue, where fibres spread forward and inward over the dorsum, joining the styloglossus. The fibres from the hyoid body may be called the hasio- glossus, those from the great cornu the keratoglossus. The triticeo-glossus rises from the cartilago triticea in the thyro-hyoid lig., and enters the tongue with the posterior part of the hyoglossus. The chondroglossus is often described as a part of the above, but is separated from it by the pharyngeal fibres of the genio-hyoglossus. Ori- gin, inner side of base of small cornu and from part of hyoid body ; its fibres end on the dorsum of the tongue near the middle line. M. Styloglossus. — Origin, front of styloid process near apex, and largely from stylo-maxillary lig. ; insertion, side and under part of tongue as far as tip, decussating and blending with the hyoglossus and palato- glossus. The lingualis is the intrinsic tongue-muscle, presenting inferior, supe- rior, transverse, and vertical fibres, with a median fibrous septum. M. myloglossiis is an accessory slip of the styloglossus from angle of jaw or stylo-max. lig. to the tongue. M. stylo-auricularis, from cartilage of exter- nal auditory meatus to styloid process or styloglossus muscle : a fibrous band is often found here. 11— A. 162 MUSCLES OF THE TRUNK. Nerves. — Motor supply by hypoglossal. Actions — Genio-hyoglossus, hinder part protrudes the tongue, front part re- tracts, middle part or nearly whole muscle depresses and makes dorsum con- cave ; in hemiplegia the sound fibres push apex over to paralyzed side. The hyoglossus and chondroglossus retract, depress, and make dorsum convex ; the styloglossus draws tongue back, elevates the base, and makes dorsum concave. Describe the muscles of the pharynx. There are two layers : an outer, called constrictors, three in number, with a transverse direction ; an inner, called elevators, two in number, with a longitudinal direction. Inferior Constrictor (laryngo-pHaryngeus). — Origin, cricoid cart, at lower and back part, inf. cornu, oblique line and upper tubercle of the thyroid cart. ; some fibres continue into it from sterno-thyroid and crico- thjToid muscles. It unites with its fellow in the median line ; its inferior fibres are horizontal, and a few enter the longitudinal layer of the oesophagus, and highest end on a raphe about 1 inch below the basilar process. Superficial fibres of one side become deep in the other, or may join the fibres of another constrictor. This covers the middle con- strictor ; the sup. laryngeal nerve and vessels enter the larynx above its upper border, and the inferior nerve and vessels beneath its lower border. Middle Constrictor (hyo-pharyngeus). — Origin, large and small cornua of hyoid, from stylo-hyoid lig. ; fibres diverge greatly, covering nearly the whole length of the pharynx, and meet behind in the median line : the lowest are beneath the inf constrictor, the highest overlap the sup. constrictor, the intermediate ones are transverse. The stjdo-pharyngeus muscle separates this from the sup. constrictor. Fibres may come from the hyoid body, tongue, or mylo-hyoid ridge ; a fre- quent slip from the lateral thyro-hyoid lig. is the m. syndesmo-pharyngeus. Superior Constrictor (cephalo-pharyngeus). — Origin, side of tongue, mucous membrane of mouth, alveolus at end of mylo-hyoid ridge, pterygo- max. lig., hamular process, and lower third of internal pterygoid plate: the fibres curve back and blend with the opposite muscle or end in the aponeurosis which fixes the pharynx to the basilar process. Of all the constrictors, only the upper half of this muscle ends in a raphe (linea alba). The upper margin curves round the lev. palati and Eustachian tube ; the space intervening, closed by fibrous membrane, is the sinus of Morgagni. These muscles are covered externally by dense connective tissue, which is prolonged forward to the pterygo-max. lig. , and is continuous with the membrane over the buccinator muscle ; hence it is called the bucco- pharyngeal fascia. Next comes the muscular layers, next the pharyn- geal apon., and next the mucous membrane.^ The m. stylo-pharyngeus rises from the inner surface of the styloid process near the root, passes down and in under cover of the middle constrictor, joined by the palato-pharyngeus, and ends on the superior and posterior borders of the thyroid cart, and lateral wall of the pharynx. PLATE XL Fig. I.— To face -page 161. Muscles of the Tongue, left side. Fig. %— To face page 170. Rectus superior. Levator \ qmlpebrce superior. Obliquus superior. Its upper head. Lower head. Rectus inferior. The Relative Position and Attachment of the Muscles of the Left Eyeball. PLATE XII. Fig. 1 . — To face page 163, ' p h a'i Muscles of the Soft Palate, the pharynx being laid open from behind. MUSCLES AND FASCIA OF THE NECK. 163 The m. palato-pharyngeus will be described with the palatal muscles. Varieties. — Splitting or doubling or a division into three parts ; supernu- merary elevators are common, passing to constrictors or fibrous wall of phar- ynx ; from petrous portion or vaginal process = petro-pharyngeus, from spine of S]^henoid = spheno-pharyngeiis, fTom hamular process = pterygo-pharynyeus ext., from basilar itrocess = occipito-pharyvgeus, from mastoid process (rare) =^7iar- yngo-mastoideus ; a small slip to raphe from pharyngeal spine =? azygos-pharyngis. Nerves. — ^Pharyngeal plexus and motor fibres from bulbar part of sp. access, n., glosso-pharyngeal also for mid. constrictor ; inf. constrictor has in addition fibres from ext. and inf. laryngeal nerve. Stylo-pharyngeus is supplied by gl osso-phar y n geal . Describe the muscles of the soft palate. The soft palate (velum pendulum palati) is continued back from the hard palate, pendulous posteriorly, prolonged in the middle into the uvula^ and laterally into the posterior pillars of the fauces^ which run to the side of the pharynx: another fold in front is the anterior pillar of the fauces^ descending to the tongue ; between them is the tonsil, and the constricted part between the anterior pillars is the isthmus of the fauces. There are five pairs of muscles — two superior, one intermediate, and two inferior. The palato-glossus (constrictor isthmi faucium, glosso-staphylinus) occu- pies the anterior pillar of the fauces : at its origin it is below all the other palatal muscles, and continuous with its fellow ; inferiorly it enters the side of the tongue and joins the transverse fibres. M. amygdalo-glossus normally ascends from the side of the tongue to the tonsil. The palato-pharyngeus (pharyngo-staph3dinus) rises by two layers which embrace the lev. palati and azygos uvulae : the superficial (pos- terior) layer is thin, the deep (anterior) laj^er is stronger, meets its fellow, and rises in part from the hard palate and apon. of the velum ; it receives one or two fibres from the cartilage of the Eustachian tube (salpingo-pharyngeus). It passes down in the posterior pillar, mingling with the stylo-pharyngeus, is inserted into the upper and hinder borders of the thyroid cartilage and fibrous laj^er of pharynx, passing to or cross- ing the median line. The azygos wpw?oe (palato-staphylinus), supposed to be single, consists of two slips which rise from the soft palate and posterior nasal spine and descend into the uvula, separated above, united below. Levator Palati (petro-staphylinus). — Origin^ petrous portion of tem- poral bone in front of carotid canal, from lower margin of cartilage of Eustachian tube, passes forward over the sup. constrictor, and is inserted by its fore part into the apon. of the palate, and posteriorly it meets its fellow under cover of the azygos uvulae. Circumflexus, or Tensor Pa/a^i (spheno-staphylinus). — Origin^ scaphoid fossa at root of int. pterygoid plate, spine of sphenoid, and outer side of Eustachian tube ; descends vertically inside the int. pterygoid muscle ; 164 MUSCLES OF THE TRUNK. its tendon turns round the hamular process, where there is a bursa, then passes horizontally to its insertion into the transverse ridge of the palate bone and apon. of soft palate. From before backward in the soft palate is the palato-glossus, tensor palati, ant. part of palato-pharyngeus, levator palati, azj^gos uvulae, post, part of palato-pharyngeus, and mucous membrane. iVerves.— Sources not fully determined : tensor palati through otic ganglion from third division of fifth ; lev. palati, azygos uvulse, palato-glossus, and palato-pharyngeus probably by bulbar portion of sp. access, nerve through pharyngeal plexus. Actions. — The constrictors are nearly immovable behind, and so carry back the anterior wall, the hyoid bone and larynx being carried up and back by the obliquity of the two lower constrictors. The upper part of the sup. con- strictor cannot act directly upon the food, as it is attached at both ends to immovable parts. The stylo-pharyngeiis is the chief elevator of the pharynx and larynx ; the palato-glossi depress the soft palate, elevate the tongue, and shut off the mouth-cavity from the pharynx; the palato-pharyngei depress the soft palate, raise the pharynx, and bring the post, pillars together; the azygos uvulse raises and shortens the uvula : the lev. palati raises the palate ; the tensor palati tightens and supports the palate against the pull of other muscles and opens the Eustachian tube in deglutition. Some hold that the tube is closed in deglutition by the lev. palati pressing its floor against its upper and outer wall. The first stage of deglutition is effected by the mylo-hyoid, stylo-glossus, and palato-glossus pressing the tongue against the palate ; the hyoid is also raised by its elevators ; the larynx is then carried up beneath the hyoid by the thyro-hyoid and stylo-pharyngeus, root of tongue is drawn back by the stylo- glossi and epiglottis pressed down ; at the same time the soft palate is raised and fixed by its proper muscles ; the post, pillars and uvula shut off the poste- rior nares, and the food is guided into the lower pharynx, where it is grasped by the constrictors in succession and forced into the oesophagus. Posterior Neck-muscles. These are divided by the trans, proc. into two groups. The outer from the processes to the ribs corresponding to the intercostals, those from the processes to the shoulder-blade corresponding to the serratus magnus ; the inner group passes from one process to another, long or short. Outer group, four in number. — 1. M. Scalenus Anticus. — Origin, anterior tubercles of trans, proc. of third, fourth, fifth, and sixth cerv. vert. ; insertion, by a thick flat tendon into the scalene tubercle and upper surface of first rib to neighborhood of the cartilage ; the pleura is at- tached to the lower part of the inner surface of this muscle. 2. M. Scalenus Medius. — Origin, tendinous above, muscular below, from posterior tubercles of trans, proc. of all the cerv. vert, (sometimes not of atlas) ; insertion, upper edge and outer surface of first rib from the tuberosity to the subclavian groove. 3. M. Scalenus Posticus, smaller than the others. Origin, by two or three tendons from the posterior tubercles of the lower two or three cerv. MUSCLES AND FASCTJE OF THE NECK. 165 vert. ; mserfion, by an aponeurotic tendon into the second rib external to the serratus post. sup. Some regard the scalenus mass as one muscle with three insertions. Varieties. — A slip from scaj^nus ant. may pass behind the subclavian artery. Scalenus post, may be absent or go to third rib. Scalenus pleuralis, from trans, proc. of seventh cerv. vert., spreads out in fascia, supporting the dome of pleura ; inserted into inner border of first rib. Scalenus minimus and lateralis, the former a slip of the anticus to the first rib, the latter of the posticus to the second rib. M. transversalis cervicis meclius, between the scalenus medius and posticus, connecting the second and fourth with the sixth and seventh trans, proc. 4. M. Levator Scapulce (lev. anguli scapulae). — Origin^ by distinct slips from the trans, proc. oiP the upper four cerv. vert, between the at- tachments of the splenius and scaleni ; msertwn, posterior border of scapula from spine to superior angle. Vertebral attachments various : a slip to it from the occipital bone or mas- toid process ; parts from vertebrae may remain separate to insertion. In quadrupeds it unites with the serratus anticus (magnus), and forms one muscle ; may send a slip to the scaleni, trapezius, serrated muscles, or first and second ribs. I)ine7' Group. — Long Muscles. — 1. M. hngus colli rests on the front of the vertebral column from the atlas to the third dorsal vert. There are three sets of fibres : [a) vertical part ^ from bodies of lower two cervical and upper two or three dorsal ; on its outer border it receives slips from the lower three or four cerv. trans, proc. ; inserted into bodies of second, third, and fourth cerv. vert. ; [h) lower oblique part^ from bodies of upper two or three dorsal, into anterior tubercles of fifth and sixth cerv. trans, proc. ; (c) upper oblique part is the m. longus atlantis of Henle. Origin^ anterior tubercles of trans, proc. of third, fourth, and fifth cerv. vert. ; inserted into the vertical portion and lateral and lower part of anterior tubercle on arch of atlas. Slip from lower oblique part may be inserted into head of first rib. M. transversalis cervicis anticus, from anterior tubercles of trans, proc. of lower four cerv. vert, to the body of the axis and trans, proc. of the atlas. 2. 3f. Longus Atlantis (see preceding muscle). 3. M. Longus Capitis^ p. n. (rectus capitis anticus major). — Origin^ anterior tubercles of trans, proc. of third, fourth, fifth, and sixth cerv. vert. ; insertion^ basilar process of occipital in front of the foramen mag- num ; it may show a tendinous inscription anteriorly ; pharynx is closely attached to it. Short Muscles. — 1. Mm. Intertransversarii Anteriores. — Anterior in- tertransverse muscles pass as little fasciculi between the anterior tuber- cles of the trans, proc. of the cerv. vert. ; they are in front of the nerve- trunks. The one for the axis is inserted broadly into its trans, proc. They may be lacking for the two upper vertebrae. 2. M. Rectus Capitis Anticus , p. n. (rect. cap. ant. minor). — Origin^ 166 MUSCLES OF THE TRUNK. front of root of trans, proc. of atlas ; insertion^ basilar process, between foramen magnum and rectus major, J inch from its fellow. Nerves. — Eectus anticus minor by first cerv. nerve ; scaleni and long pre- vertebral muscles by neighboring nerves ; the J/evator scapulae by the third, fourth, and fifth cerv. nerves. Actions. — The scalene muscles are elevators of the ribs, muscles of inspira- tion ; fixed at the ribs are lateral flexors of the neck, or both sides together bend it forward ; the recti antici flex the head and throw forward the phai*- ynx ; the longus colli flexes the neck, and its oblique parts may rotate; the levator scapulse elevates the superior angle and base of scapula, counteracting the rotation of the trapezius ; fixed below, draws neck back and to one side. MUSCLES OF THE HEAD. Describe the head-muscles. These belong to the skull and f^ce ; those of the face are in three groups and in three layers. Epicranial Muscles. M. Upicramus, p. n. (occipito-fron talis), comprises the occipital and frontal muscles on either side, united by the Galea aponeurotica. p. ii. (epicranial apon.). This covers the upper surface of the skull without division, closely attached to integument and loosely to pericranium. Behind, it is attached to the occipitales muscles, to the occipital pro- tuberance, and supreme curved lines; anteriorly it terminates in the frontales ; laterally has no distinct margin, but beneath it a thin fascia springs from the superior temporal line and passes under the auricular muscles to the pinna. The frontalis muscle (m. epicr. frontalis) rises from the aponeurosis between the coronal suture and frontal eminence ; inferiorly it ends in subcutaneous tissue at the root of nose (pyramidalis nasi is a part of it, Henle), inner canthus of eye, and whole length of eyebrow, continued into the pyramidalis nasi and interlacing with the corrugator supercilii and orbicularis ; the margins of the right and left are united near the root of the nose, but separated higher up. The occipitalis mu.'icle (m. epicr. occip. ) is attached to the outer two- thirds of the superior curved line and to the mastoid process : its fibres, 1 to 2 inches long, terminate in tendon, and that in aponeurosis; an interval between the muscles is occupied by aponeurosis. Henle describes the auricular mmcles as a part of the epicranius ; the m. epicr. temporalis is the auricularis anterior of Quain ; rises from the root of the zygoma and bony external auditory meatus ; connected with the helix and capsule of lower jaw, its fibres pass up and forward to the edge of the frontalis muscle and orbicularis oculi, and meet the platysma below. The m. {epicr.) auricularis superior rises from the Galea apon., and converges to the helix by one tendon, and by another to an eminence on the inner surface of the pinna. MUSCLES OF THE HEAD. 167 The m. (epicr.) aurimlaris posterior rises from the mastoid, sterno-mas- toid apon. , and outer part of superior curved line, and is inserted into the vertical ridge at the back of the concha. All of the ear-muscles are more or less connected. The post, auricular muscle may rise far back along the superior curved line. A deep anterior auricular muscle may pass normally from the zygoma to the tragus. Actions, — The frontales elevate eyebrows, draw scalp forward, and wrinkle forehead transversely ; occipitales draw scalp back or may alternate with the frontales. Most persons have only partial control, best in case of frontales. The actions of the ear-muscles are slight or nil ; the anterior makes tense the temporal fascia, and has no effect on the ear ; they may enlarge the entrance to the external ear. Muscles of Eyelids and Eyebrow, M, orbicularis oculi^ p. n,^ has three parts, is thin and elliptical, covers the eyelid, and extends some distance on the forehead, temple, and cheek. The pars palpebral is J p, ??., is contained in the eyelids, rises from the upper and lower margins of the int. tarsal lig. , and passes out in a slight curve to the ext. tarsal lig. A thicker fasciculus along the free margin of each lid is the ciliary bundle. The pars orbitalis^ p, n. , is larger and stronger, attached to the nasal process of the superior maxilla, inner part of orbital arch, and externally to the cheek, forming a series of concentric loops. The m. malaris of Henle are the lower converging fibres of the orbital part, passing to the skin of the cheek and muscles of upper lip. The pars laclirymalis^ p. n. (tensor tarsi or Horner's musde), extends from the lachrymal crest behind the sac, and divides into two slips be- hind the lachrymal canals for the ciliary bundles of the orbicularis. The internal palpebral ligament (tendo oculi) is 2 lines long and at- tached to the nasal process of the sup. maxilla in front of the lachrymal groove ; thence it passes to the inner commissure of the eyelids, spUt- ting and terminating on the tarsi ; it crosses the lachrymal sac in front, and gives off a process which passes behind the sac to the crest of the lachrymal bone. The external palpebral lig, is weaker, and attaches the lids to the ma- lar bone. The corrugator supercilii (described by Henle as a part of the orbic- ularis) rises from the glabella, and passes up and out to end at the mid- dle of the orbital arch in the orbicularis and skin of eyebrow. The levator palpebrce sup, will be described with the orbital muscles. Actions. — Palpebral part closes the lids ; upper half of orbital part depresses the eyebrow and opposes the frontalis, used in forcible closure of lids; in common winking the palpebral part carries forward the int. palpebral lig. and anterior wall of lach. sac, and sucks in tears ; the pars lachrymalis (ten- sor tarsi) probably alternates with the palpebral part, draws back the palpe- bral lig., and compresses the sac. The corrugator produces vertical wrinkles at the inner end of the eyebrow. 168 MUSCLES OF THE TRUNK. Muscles of Face. First Layer. — In muscular individuals this may be a continuous layer under the skin, converging to the corners of the mouth, but it is usually divided into — 1. M. zygomaticus^frmnmsilsiY hone near zygomatic suture to angle of mouth, inserted into skin and mucous membrane by two layers, mingling with the levator and depressor anguli oris. The so-called zyg. minor is very inconstant, and is best described as a head of another muscle. 2. M. risorms (Santorini), thin fasciculi from masseteric' or parotid fascia passing over platysma to skin at angle of mouth ; is not a part of the platysma. May rise from skin over sterno-mastoid, from zygoma, external ear, or fascia over mastoid ; may be double or triple. ^ 3. M, triangularis menti (depressor anguli oris), from external oblique line of lower jaw ; fibres converge partly to skin at angle of mouth, and partly to orbicularis of upper lip ; anterior edge is concave and posterior convex. M. transversus menti, from inner border of the depressor down aud in below chin, across median line to corresponding point on other side. At the corner of the mouth the various decussating muscular fibres give rise to a dense mass or knot external to the lip-commissure. ^ Second Layer. — 1. M. quadratus lahii sup.^ p. 7i., lies along the side of nose, from orbit to upper lip, and rises by three heads — caput an- gulare^ p. n. , = levator labii sup. alaeque nasi ; caput infraorhitale^ p. n. , ^■lev. labii sup. proprius ; and caput zygomaticum^ p. tz., = zygomat. minor. Caput angulare rises from nasal process of sup. max., generally connected with the frontalis, and separates into two fasciculi below — one to the skin of the wing of the nose, the other to the skin of the upper lip or cheek, blending with the orbicularis oris and the next head. The middle head, caput infraorhitale, rises from the anterior surface of the upper jaw and its malar process in a line passing from above the infraorbital foramen down and out to the suture between the sup. max- illa and malar bones, and inserted behind the caput angulare into the skin of the wing of the nose and of the upper lip. The outer head, caput zygomaticum (zygomaticus minor), rises from the tuberosity of the malar, strengthened by bundles of the malaris mus- cle, and passes to skin of upper lip and to the caput infraorbitale (lev. labii sup.). 2. M. Caninus (levator anguli oris). — Origin^ canine fossa below in- fraorbital foramen, covered by the quadratus ; passes down and out to skin at the angle of the mouth, and a large number of fibres decussate with the depressor anguli oris or are continued to the orbicularis of the lower lip ; it almost always receives a slip from nasal process of the sup. maxilla close under the caput angulare. MUSCLES OF THE HEAD. 169 3. M. Quadratm Menti (depressor labii inferioris). — Origin^ lower jaw from near symphysis to beyond the mental foramen ; passes in to its fellow, and inserted into the skin of the lower lip and orbicularis ; it is really a continuation of the platysma. Third Layer. — Lateral Muscles. — M. huccinator (trumpet muscle), a flat layer forming a large part of the wall of the mouth ; attached at upper and lower margins to alveoli of maxillary bones opposite the molar teeth, posteriorly to the pterygo-maxillary hg., separating it from the superior constrictor of the pharynx ; fibres become thickened at angle of mouth and join the orbicularis ; higher and lower fibres are directed to corresponding lips, middle ones decussate, the upper to the lower hp, the lower to the upper lip. Median Muscles. — 1. Sphincter oris^ or m. orhicidaris oris, is an ellip- tical sheet making the foundation of the lips, composed largely of trans- verse and vertical fibres from the buccinator and elevators and depressors of the angle of the mouth ; there are also sagittal fibres between the skin and mucous membrane. The deeper fibres and a distinct marginal band from the buccinator pass from side to side without interruption ; the le- vator and depressor anguli fibres, which have crossed at the corner of the mouth, enter the more superficial parts and are inserted into the skin of the middle portion of the lip, mostly after crossing the median line and decussating with their fellows ; these do not reach the free bor- der of the Hp. 2. Mm. incisivi attach the orbicularis to bone. The upper lip has two slips on each side, an outer, or m. indsivus svp., from the incisor fossa, and an inner, m. nasodabialis, from the septum of the nares ; the lower lip has one fasciculus on a side, m. indsivus inf. . from the incisor fossa. These all pass out toward the corners of the mouth. ^ The sagittal fibres are more developed in the infant, are in the mar- ginal portion, and constitute the m. labii proprius. 3. M. nasalis, p. n., includes slips usually distinguished as compressor naris and depressor alee nasi (outer part). The former rises from the sup. maxilla by the side of the anterior nasal aperture,^ and meets its fellow in the median line over the cartilages of the nose in an expansion com- mon to it and the pyramidalis nasi. The depressor alee nasi rises from the incisor fossa, and is inserted by its outer part into the back of the ala of the nose, and by its inner part into the septum, called depressor septi, p. n. The pyramiidalis nasi is a prolongation of the frontalis, decussating with its fibres, and attached to skin at the lower median part of the fore- head and to the tendinous expansion of the compressor naris below. There are other indistinct fibres of nasal muscles — the dilator naris posterior and anterior. M. anomalus of Albinus is frequently present beneath the common elevator of lip and nose (quadratus labii sup.), passing from nasal process of sup. maxilla to same bone below, connected with comp. naris. 170 MUSCLES OF THE TRUNK. 4. M. mentalis, p. ??., levator labii inf. or lev. menti, from incisor fossa of lower jaw, passing down between depressors of lower lip to integu- ment of chin ; it forms the furrow of the chin. ^ At the apex of the chin between the periosteum and soft parts is some- times a bursa. M. anomaliis menti usually continues the above fibres to the region of the mental foramen. Nerves. — All the muscles of head and face above described (muscles of ex- pression) get their motor supply from the facial ; perhaps the frontalis and orbicularis oculi are supplied from the oculo-motor nucleus, and not the facial. Actions of the nasal muscles are indicated by their names : the pyramidalis nasi wrinkles the skin at the root of the nose and draws down that of the fore- head ; dilatation of the alae is not usually seen unless in dyspncea. Of the lip-muscles, the orbicularis oris draws the lips together vertically and trans- versely and presses them against the teeth ; the zygomaticus draws the angle of the mouth up and back ; the risorius retracts the angles of the mouth ; the buccinator flattens the cheek, keeps food between the teeth, or expels air from the mouth : thfi levator menti draws up the chin integument, and so protrudes the lower lip. Actions of other muscles are indicated by their names ; all have to do with the expression of passions. Describe the muscles of the orbit. There are seven for description. The m. levator pdlpebrce superioris [origin^ above optic foramen and sup. rectus) ends in a membranous ex- pansion ; inserted into the fibrous tarsus of the upper eyelid. A thin superficial layer is continued over the tarsus to the skin of the lid ; some fibres are attached to the conjunctiva, to the wall of the orbit, and to the trochlea. The four straight muscles have a continuous tendinous origin at the apex of the orbit from a ligamentous ring which encircles the optic foramen and crosses the sphenoidal fissure ; most of the fibres spring from two common tendons: the upper one rises from the inferior root of the small wing of the sphenoid, and is prolonged into the internal, supe- rior, and external recti; the lower (Zinn) rises from the body of the sphenoid and divides into three slips for the internal, inferior, and ex- ternal recti. All the recti are inserted into the sclerotic 3 or 4 lines from the cornea ; the external has two heads, between which pass the third, nasal branch of the fifth, the sixth nerve, and ophthalmic vein. The external and inferior recti are the longest, internal broadest, and supe- rior smallest. ^ The superior ohh'que, or trocJdearis, is internal to the lev. palpebrae, rises just in front of the optic foramen, and passes forward to a round tendon which plays through a fibro-cartilaginous ring attached to the trochlear fossa of the frontal : it is there bent out, back, and down be- tween the sup. rectus and eye, and is inserted beneath the outer edge of the sup. rectus midway between the cornea and optic nerve. The pulley is lined by a synovial sheath. MUSCLES OF THE HEAD. 171 The inferior oblique rises from the orbital plate of the sup. maxilla close outside the orifice of the nasal duct : the muscle passes out, back, and up between the inferior rectus and floor of orbit, and is inserted under cover of the ext. rectus at the back part of the eyeball, nearer to the optic nerve than to the cornea. Varieties. — M. tensor trochlex is a muscular slip from the lev. palpebrse to the trochlea ; the occasional gracilUmus rises with the sup. oblique and passes beneath it to the trochlea ; the ext. rectus may have separate heads to the insertion. An accessory inf. rectus may pass from the inf. rectus to the inf. oblique ; the transversus orhitse is an arched muscle from the orbital plate of the ethmoid across the upper surface of the eyeball to the outer wall of the orbit. Nerves. — External rectus by the sixth nerve, sup. oblique by the fourth, and the other five by the third nerve. Actions. — Lev.palpehrx is the elevator of the upper lid and antagonist of the palpebral part of the orbicularis. The eyeball seems to move on a central fixed point without shifting its place as a whole within the orbit ; four move- ments are possible: (1) lateral; (2) elevation and depression; (3) oblique movements of elevation and depression ; (4) rotation about a sagittal axis. The ext. and int. recti produce only lateral movements ; the sup. and inf. recti have their line of direction internal to the centre of motion, and. so produce not only elevation and depression, but also inward direction and slight rota- tion : this is corrected by the oblique muscles, the inf. oblique being associated with the sup. rectus, and sup. oblique with the inf. rectus ; the sup. oblique turns the cornea down and out, the inferior up and out. Around the orbit is soft fat and the capsule of Tenon, forming a socket at- tached in front to the ocular conjunctiva: a large lymph-space is between it and the eye ; it is pierced by the eye-muscles and sends a tubular prolongation upon each. The suspensory ligament of the eye is a thickening of the lower part of the capsule, attached at each end to the orbital margins and support- ing the eye in its socket. Muscles of Mastication. There are four pairs, two outside and two inside the jaw-bone. The masseteric fascia is a part of the deep cervical, covers the masseter mus- cle, invests the parotid gland (parotid fascia), and forms the stylo-max- illary ligament. ^ 1. M. masseter^ a quadrate muscle with two parts: the superficial part rises from the sup. maxilla, malar, and lower border of zygoma for its anterior two-thirds by tendinous bundles which project between the mus- cular fasciculi ; it passes down and back to lower half of jaw from angle to third molar tooth ; the deep part is triangular, and passes nearly ver- tically from the posterior third of zygoma, lower border, and from all the deep surface of the arch ; inserted^ after uniting with the superficial part, into the upper half of the ramus and coronoid : this is almost wholly covered by the superficial portion. There may be a bursa between these two parts. The buccal fat-pad is between the fore part of the masseter and the bucci- 172 MUSCLES OF THE TRUNK. nator, and is prolonged into the zygomatic fossa : it is well developed in the infant, and inappropriately called the "sucking pad." The temporal fascia is a dense apon. covering the temporal muscle above the zygoma : it is attached to the temporal crest of the frontal and upper temporal line, and below divides into two layers attached to the inner and outer surfaces of the Z3^gomatic arch ; it is separated from integument by a lateral projection of the Galea apon. and by the supe- rior and anterior auricular muscles. 2. M. temporalis rises, fan-shaped, from the whole of the temporal fossa, not its anterior malar wall, which is covered with fat, from the deep surface of the temporal fascia, and may blend with some deep fibres of the masseter. The anterior fibres are nearly vertical, the pos- terior nearly horizontal ; all converge to a tendon which is inserted into the upper and anterior borders of the coronoid, and deeper fibres have a fleshy insertion into its inner surface as far as the union of the ramus and body of jaw. M. temporalis minor occasionally goes from the fibro-cartilage of the temporo- maxillary articulation to the sigmoid notch of the lower jaw. 3. M. pterygoideus externum occupies the zygomatic fossa, and rises b^ two heads, the upper and smaller from the zygomatic surface of the great wing of the sphenoid and infratemporal crest; the lower and larger from the outer surface of the ext. pterygoid plate. The fibres from both pass back, converging to a fossa on the front of the neck of the lower jaw, to the interarticular cartilage and capsule. A venous plexus is between its upper surface arid base of skull. M. pterygoideus proprius is a vertical band from the infratemporal crest out- side the ext. pterygoid to the outer pterygoid plate or tuberosity of palate- bone or sup. maxilla. M. pterygo-spinosus, from the spine of the sphenoid to the outer pterygoid plate between the two pterygoid muscles : this is frequently a pterygo-spinous ligament f and may be converted into bone. 4. M. pterygoideus internus rises also by two heads — one from the pterygoid fossa, mostly from the inner surface of the external plate, from the tuberosity of the palate between the two plates; a second small slip outside the ext. pterygoid muscle from the tuberosities of the palate and sup. maxilla: fibres pass down, back, and out to the inner surfiice of the ramus between the angle and dental foramen ; it is dis- posed much like the masseter. Nerves. — All from the inferior maxillary division of the fifth. Actions. — Masseter, temporal, and int. pterygoid elevate the lower jaw; as de- pression is not much resisted, it is accomplished by smaller muscles, chiefly the digastric; ext. pterygoid protrudes the lower jaw, or alternately produces a grinding of molar teeth ; it may also assist in opening the mouth when the condyles are carried forward upon the artic. eminences. The hinder portion of the temporal and the deep part of the masseter retract the jaw. MUSCLES AND FASCIA OF THE EXTREMITIES. 173 MUSCLES AND FASCIA OF THE EXTREMITIES. The Upper Extremity. THE SHOULDER. Describe the scapular muscles and fasciae. The deep fascia is strong and tendinous over the back of the deltoid and infraspinatus ; the infraspinatus fascia covers the teres minor and sphts at the posterior border of the deltoid, a deep layer passing to the shoulder-joint under that muscle, a superficial la3^er to the spine of the scapula over the muscle. {a) Vertical Scapular Muscles. M. Deltoideus. — Origin^ in three portions: an anterior from the front of the outer third of the clavicle, a middle from the point and outer edge of the acromion, a posterior from the lower border of the scapular spine and triangular surface at its inner end, and from infraspinatus fas- cia. These converge into the tendon of insertion into the deltoid tuber- cle of the humerus. The anterior and posterior parts run by long fas- ciculi into the marginal parts of the tendon : in the acromial portion most fibre.^ rise in a bipenniform manner from the sides of four tendinous septa ; the oblique fibres are inserted below into three septa which come up from the humerus to alternate with those above. Some fibres pass from the tip of the acromion to the tips of the lower septa, and some from the tips of the upper septa directly to the humerus. Fibres continued into the trapezius, as in animals lacking clavicles ; addi- tional slips from ext. or int. border of scapula (basio-deltoideus Meckelii) ; a prolongation of its tendon to the insertion of the supinator longus, connected inseparably with the pect. major; m. acromio-davicularis lat. from the acro- mial end of the clavicle to the acromion and origin of deltoid ; may be a subdeltoid muscle. (h) Posterior Scapular Muscles. 1 . 31. supraspinatus^ from inner part of supraspinous fossa to region of the notch, from supraspinous fascia and trans, ligament; adherent to capsule and infraspinatus tendon ; inserted into the upper of the three facets on the great tuberosity of the humerus. 2. M. infraspinatus ri^es from thQ inner two-thirds of the infraspinous fossa, from the infraspinatus fascia, and under surface of the spine ; fibres converge to a tendon concealed within the muscle and inserted into the middle facet of the great tuberosity. It may be inseparably connected with the teres minor. 3. M. Teres Minor.— Origin^ from narrow grooved surface or dorsum of scapula close to axillary border, from septa between it, the teres major, and infraspinatus ; inserted into lowest facet on great tuberosity and into shaft for a short distance below. 174 MUSCLES AND FASCIA OF THE EXTREMITIES. May be a bursa under its insertion. It is behind the long head of the triceps and capsule ; the dorsal scapular artery passes between it and bone. (c) Anterior Scapular Muscles. M. Suhscapularis. — Origin^ by muscular and tendinous fibres from venter of scapula and groove along the axillary border ; insertion^ small tuberosity of humerus and into shaft for a short distance. As in the deltoid, this muscle contains two sets of septa — one from the origin, and one from the insertion for attachment of oblique muscular fibres. Some fibres from the axillary border of the muscle are usually inserted into the capsule, known as the suhscapularis minor. There is a bursa between the muscle and the capsule, and often another on its anterior surface (bursa coraco-brachialis). Nerves. — Supra- and infraspinatus by suprascapular nerve from fifth and sixth cervical ; others from post, cord of brachial plexus, detoid, and teres minor from fifth and sixth cervical through circumflex nerve; suhscapularis by fifth and sixth cervical through upper and lower subscapular nerves. Actions. — Deltoid abducts arm to 90°, posterior fibres said to abduct only to 45° ; insertion of trapezius corresponds to origin of deltoid, so that the two are continuous in action : anterior part of the deltoid draws the humerus forward and rotates in ; of both deltoids crosses the arms over the chest ; posterior part draws humerus backward and rotates out ; supra-, infraspinatus, and suhscap- ularis steady the capsule while deltoid acts. The supraspinatus only abducts. The infraspinatus rotates out and carries the arm back when it is raised. The suhscapularis rotates in and carries the arm forward when it is raised. The teres minor rotates the raised humerus out and depresses it. All act as liga- ments to the joint. THE UPPER ARM. Describe the muscles and fascise of the upper arm. The aponeurosis of the arm (deep fascia) is thin over the biceps, strong over the triceps, and is attached to the humerus by intermuscular septa (ligg. intermuscularia). The external intermiiscular septum extends from the outer epicondyle and supracondylar ridge to the deltoid inser- tion : it is pierced by the musculo-spiral nerve and sup. profunda artery. The internal intermuscular septum extends from the inner epicondyle and inner supracondylar ridge to behind the coraco-brachialis : it is pierced by the anastomotica magna artery. The internal brachial lig. of Struthers is a fibrous band below the teres major insertion to the inner epicondyle : the ulnar nerve and inf pro- funda artery pass between this band and the int. intermuscular septum. (a) Muscles of Anterior Surface. First Layer.— M. Biceps (brachii). — Its short or inner head rises with the coraco-brachialis from the coracoid ; the long head, from the upper end of the glenoid cavity within the capsule by a tendon continuous on THE UPPER ARM. 175 each side with the glenoid ligament: these two heads form a belly in the middle and lower part of the arm. The tendon of insertion is slightly twisted and attached to the back part of the tuberosity of the radius, separated from the fore part by a bursa ; may be a second bursa between the tendon and ulna. From the inner side of the tendon a part branches off as an aponeurotic band or semilunar fascia (lacertus fibrosus, p. n.), and blends with the deep fascia of the forearm stretched across the brachial vessels and median nerve. One of the most variable muscles: a third head (10 per cent, of cases) rises from humerus, connected with brachialis anticus and coraco-brachialis, and inserted into coracoid portion of muscle and semilunar fascia : this is usually outside the brachial artery ; a head may come from outer side of humerus, bicipital groove, or great tuberosity ; may be two additional heads or even three. It may give off a slip to the internal intermusc. septum or inner con- dyle or pronator teres. Absence of long head : it was originally extracapsu- lar, but has become covered by the coraco-humeral lig., a part of the pect. minor. The semilunar fascia represents an ulnar division and corresponds to the fascial insertion of the biceps fem. Second Layer. — 1. M. Coraco-hrachiah's. — Origin^ tip of coracoid between pect. minor and short head of biceps, conjoined with the latter ; insertion^ inner border of humerus near its middle, between triceps and brachialis anticus; higher up some of its fibres are often inserted into a fibrous band arching over the lat. dorsi and teres major tendons, and at- tached close to the small tuberosity. It is usually pierced by the mus- culo-cutaneous nerve. Many varieties, which seem to indicate it is formed of three parts — viz. (1) a superior short part, from coracoid to small tuberosity (m. coraco-capsularis to capsule) ; (2) middle part, corresponding to the muscle usually seen ; (3) infe- rior part, to inner epicondyle or supracondylar process (coraco-brachialis minor). The middle part is most constant in man, but is usually accompanied by a part of the third, with the musculo-cut. nerve between them. It may send a slip to the brachialis anticus or internal septum or int. brachial lig. 2. M. hrachialis anticus (brachialis internus, p. n.) rises from the lower half of i\iQ front of the humerus, nearly the whole of the int. intermuscular septum, and upper part of the external : it embraces the deltoid insertion by two processes, the outer of which is in the spiral groove as far as the upper limit of the deltoid tubercle. It is adherent to the capsule of ^ the elbow-joint, and often sends a slip into it, and is inserted into the inner part of the rough surface at the junction of the coronoid with the shaft of the ulna. The muscle may be subdivided into two, united with neighboring muscles, or send a slip to the semilunar fascia or radius. ip) Posterior Muscles of the Upper Arm. M. extensor triceps occupies the whole posterior brachial region. Three heads are inserted into a common tendon occupying the posterior surface 176 MUSCLES AND FASCIA OF THE EXTREMITIES. of the muscle from the middle of the arm to the elbow. The middle or long head (anconeus longus — anconeus was a term applied to any muscle attached to the olecranon) rises from the inf glenoid tubercle of the scapula and^ adjacent portion of axillary border : this forms the middle and superficial part of the muscle and ends on the inner margin of the tendon. The external head (anconeus brevis) rises above the spiral groove and from an aponeurotic arch of the external intermusc. septum as it crosses it, extending to the teres minor insertion above, and inserted into the upper end and outer border of tendon. The internal or deep head (anconeus internus) rises from the whole posterior surface of the humerus below the spiral groove, from the lower part of the external in- termusc. septum, from the whole of the internal, as high as the teres major : some of its fibres are inserted directly into the olecranon, but most join the deep surface of the tendon. The common tendon is inserted into the tuberosity of the olecranon, and externally a band is prolonged over the anconeus to the fascia of the forearm and posterior border of ulna : it may send a slip to the capsule. On removing the triceps a few muscular shps are sometimes found from the bone to the capsule, analogous to the subcrureus, and described by some as distinct from the triceps called the suhanconeus. There is a bursa between the tendon and olecranon or in the tendon, sometimes one between the integument and tendon, rarely one between the tendon and ulnar nerve (retro-epi trochlear). Varieties. — Fourth head from inner part of humerus ; a slip between triceps and lat. dorsi, the anconeus quintus or dorso-epitrochlearis of animals; the an- coneiis-epitrochlearis from the inner epicondyle to the olecranon, bridging over the ulnar nerve and generally present as a band of fascia. Nerves. — Coraco-brachialis by branch from outer cord (7 c), biceps by mus- culo-cut. (5, 6 c), brachialis anticus by musculo-cut. and musculo-spiral, tri- ceps by musculo-spiral (7, 8c.). Actions. — Biceps flexes arm at shoulder and forearm at elbow ; after prona- tion of forearm it is a powerful supinator and makes tense the fascia of the forearm ; its inner head and coraco-brachialis draw arm in as well as up. The brachialis anticus is a simple flexor at the elbow. Triceps, int. and ext. heads are extensors at the elbow ; the long head extends the arm on the scapula, keeps the head of humerus in place, and assists in extending the forearm. These muscles may act from distal fixed points, as in climbing. THE FOREARM. Describe the muscles and fasciae of the forearm. The superficial fascia is most distinct at the elbow, contains the super- ficial veins, and below connects the skin with palmar fascia. The aponeurosis of the forearm (deep fascia) is composed largely of transverse fibres, strengthened by expansions from the condyles of the humerus, olecranon, and fascia over biceps and triceps. The anterior part is weaker than the posterior, and continuous below into the ant. annular ligament (lig. carpi volare, p. n. ) : it sends in a thin layer be- THE FOKEARM. 177 tween the superficial and deep muscles. The posterior portion sends off septa between the muscles and forms the post, annular ligament (lig. carpi dorsale, p. n.). Anterior Group ^ Pronato-flexor. Eight muscles, five superficial and three deep. Superficial Layer. — All from a common tendon in the following order from without in : 1. M. pronator teres rises by two heads, the larger from the upper part of the inner condyle, common tendon, fascia, and intermuscular septum ; second head, thin and deep, from inner margin of coronoid ; insertion, middle of outer surface of radius. The ulnar artery is beneath this muscle, and median nerve between its heads. Liable to be injured in the "back stroke" of lawn tennis. Coronoid head maybe absent; slip from intermusc. septum above inner condyle or from supracondylar process; additional head from biceps or brach. anticus. 2. M. flexor carpi radialis (m. radialis internus) rises from the com- mon tendon, fascia of forearm, and septa between it and the pron. teres, palmaris longus, and flex, sublimis ; tendon begins below middle of fore- arm, passes through a special compartment of the ant. ann. lig., through a groove in the trapezium ; inserted into the base of the second meta- carpal bone, anterior surface, and usually by a small slip to the base of the third. Absence of muscle ; inserted into ann. lig., trapezium, or fourth metacarpal ; receives slip from biceps or its fascia, coronoid process, or oblique line of radius. 3. M. palmaris longus is placed between the ulnar and radial flexors of the carpus, resting upon the flex. subl. ; rises from common tendon, fascia, and septa, forming a short muscular belly ending in a slender tendon, inserted into the palmar fascia, and sends a slip to the abductor poll. , sometimes one to the httle finger muscles. Most variable muscle of body, lacking oh both sides in one-third of the cases, on one side in one-half the cases (Hallett). Muscular belly may occupy the middle of the tendon, lower end, both ends, or be absent ; may be double or have additional origin from coronoid or radius. Inserted into fascia of fore- arm, flex, carpi uln., pisiform, scaphoid, or little finger muscles. This muscle with the central part of the palmar fascia was a superficial flexor of the fingers, but has been reduced by the development of the other flexors. 4. M. flexor carpi idnaris (m. ulnaris int.) is the innermost of the superficial group ; rises by two heads, one from the common tendon, and one from the inner side of the olecranon and upper two-thirds of the post, border of the ulna, connected with the deep fascia of the forearm ; muscular fibres end in a tendon along its anterior margin ; inserted into the pisiform, by a small band to the ant. ann. lig. , and prolonged by the 12— A. 178 MUSCCES AND FASCIA OF THE EXTREMITIES. piso-metacarpal and piso-uncinate ligaments to the fifth metacarpal and unciform.: The ulnar nerve and post, ulnar recurrent artery pass between its two heads : the pisiform throws this tendon forward, so that the ulnar pulse cannot be felt so well as the radial. Additional sHp'from coronoid; insertion into ann. lig. or fourth and fifth metacarpals. * Monro thinks there is a bursa between its tendon and the pisiform. , 5. M. flexor sublimis digitorum (perforatus), placed behind the pre- ceding, rises &!/ three heads : (1) inner condyle by common tendon, fibrous septa, and int. lateral lig. ; (2) inner margin of coronoid; (3) ant. oblique line of radius ; divided below into four parts ending in tendons inserted into the second phalanges of the four inner digits. Through the ann. lig. they are placed in pairs : the anterior pair are for the ring and mid- dle fingers, the posterior for the index and little fingers. In the palm they diverge and enter a sheath with the flex, prof ; opposite the bases of the first phalanges the tendon divides and folds round the deep flexor, and is reunited behind it ; the two portions again separate and pass on each side to the middle of the lateral border of the second phalanx. The arrangement into pairs corresponds to a division into layers, which can be separated nearly to the inner condyle; the middle finger receives the radial head, the ring-finger tendon is joined by a slip from the deep layer; this deep layer is a digastric muscle from the inner condyle, int. lat. lig., and coronoid ; the conical belly ends in a tendon above the middle of the fore- arm, from which rise (1) a fleshy slip to the ring-finger tendon, (2) a belly for the index-finger tendon, (3) small belly furnishing the little-finger ten- don. There is usually a slip from the condylo-ulnar head to the flex. long, poll, tendon. Varieties. — Absence of radial head ; of little-finger portion, which may be replaced by a slip from ann. lig., palmar fascia, flex, prof., or fourth lumbri- calis ; a frequent slip to the flex. prof. A bursa in its tendinous origin or be- tween it and the pron. teres in 1 per cent, of cases. Deep Muscles. First Layer. — 1 . M. flexor profundus digitorum ( perforans). — Origin (not from humerus), three-fourths of inner and anterior surface of ulna, from not quite the ulnar half of the interosseous membrane for the same distance, and from an apon. attached to the post, border of the ulna, com- mon to it and flex. c. ulnaris. Only one tendon (for inderx finger) sep- arates above the wrist ; in the palm, as the tendons diverge, they give origin to the lumbricales ; over the first and second phalanges the tendon is bound down by an osseo-aponeurotic sheath, and opposite the first phalanx it passes through an opening in the flex. subl. tendon, and is finally inserted by an expanded end into the base of the last phalanx : over the middle and last phalanx its tendon is marked by a longitudinal furrow or cleft. The index-finger portion is usually separate throughout, and comes mostly THE FOREARM. ^^ jla-finger portions from the interosseous membrane ; between the ring- ay iittj a considerable part of the inner surface of the ulna isjrftfi tachment. a M. accessorius, from the common tendon of the supemcial muscles. The sheaths of the flexor tendons are opposite t^^^rst and second phalanges, and formed of strong transverse bands, u^i^Mwinalia ; o^,^^ posite the joints the bands change into a thin mernbra^^^^gi^tl^jll^ by obUque decussating fibres, so that there are anniday^^ftitiiSiiMS^f^ fibres, crudal and ohlique. The sheath has a synovial lining containing small folds, vincula tendimim or ligg. mucosa, passing between tendons and bones. There are two sets: Ugamenta hrevia. broad, four-sided, and membranous, passing between both the superficial and deep tendons near their insertions and the lower part of the phalanx just above the joint-capsule ; the Ugamenta longa^ less constant, join the tendons at a higher level. Contained in the lig. breve of the deep flexor is a small band of yellow elastic tissue, lig. suhflavum, passing from the tendon to the head of the second phalanx. 2. M. flexor longus pollicis rises from the anterior surface of the radius, from its oblique line to the edge of the pron. quad., and from the adja- cent part of the interosseous membrane, and usually (27 out of 36 cases) receives a slip (fasciculus exilis) from the inner epicondyle or coronoid. The tendon passes between the sesamoid bones of the thumb and enters a canal similar to that of the other flexors, to be inserted into the base of the last phalanx of the thumb. Its complete separation from the flex, prof is characteristic of man. May have a slip from flex. subl. or prof, or pronator teres ; may be inserted into index finger or first lumbricalis. M. flexor carpi radiaUs brevis oy profundus (6 out of 70) rises from outer sur- face and anterior border of radius between insertions of pron. teres and supi- nator longus ; insertion, very variable into tendon of flex c. rad. or bones of carpus or metacarpus ; more often present in the right arm. 31. ulnaris int. brevis (m. flex. c. ulnaris brevis) is a corresponding muscle from lower fourth of anterior surface of ulna to unciform. Second Layer. — M. pronator quadratus^ close to bones behind the last two muscles, quadrilateral and flat, from pronator ridge and inner part of anterior surface of ulna for lower fourth, from radio-carpal joint ; inserted into fore part and inner side of radius for less than its fourth. Maybe absent, subdivided into two or three layers, extended further up than usual, prolonged down as radio-carpal or ulno-carpal muscle ; a slip from ulna to trapezium or scaphoid = m. cubito-carpeus. Being bound to radio-ulnar capsule, it prevents its folding in pronation movements. Nerves. — Six and one-half of the above muscles by the median nerve, one •^ rJ3 QD -1-3 ^ o CD ^J ^ fi Fig. 2.— To face page 347. Eight Ejaculatory duct. i >1 ■s a ^.1 II THE TESTES. 345 oblique and the conjoined tendon ; and Poupart's ligament is below. The left cord is the longer. Of what is the spermatic cord composed ? It is composed of the spermatic artery, artery of the vas deferens, and cremasteric artery, the spermatic veins from the back of the testis, which receive the veins from the epididymis to form the pampiniform plexus, a number of large lymphatics, and the spermatic plexus of the sympa- thetic, together with the vas deferens, the layers of fascia which cover the testicle, and the remains of the peritoneal testicular process. What are the boundaries of the inguinal canal ? The inguinal canal is bounded behind by the fascia transversalis and the conjoined tendon ; in front by the transversalis and internal oblique above, and tlie external oblique aponeurosis below ; its floor is formed by the curving back of Poupart's ligament ; its roof by the arched fibres of the internal oblique in apposition with the aponeurosis of the external obUque. Give the coverings of the testicle. The testicle is covered from without inward by the following structures : the scrotum, composed of skin and dartos; the intercolumnar or ex- ternal spermatic fascia; cremasteric fascia; infundibuliform fascia, or internal spermatic fascia ; tunica vaginalis. What is the scrotum? The scrotum is a pocket which contains the testicles and part of the spermatic cords, and is marked superficially by a median ridge, the raphe, which runs from the penis along the scrotum and perineum to the anus. The scrotum consists of a layer of skin and the dartos. The sJcm is thin and dark, and presents folds or rugae, is covered with hairs thinly scattered, and is furnished with sebaceous glands. The dartos is a thin contractile tunic, of a reddish color, continuous with the superficial fascia of the groin and perineum ; it is very vascular, and is composed of loose areolar tissue and unstriped muscle. It sends in a partition, the septum scroti, which separates the two testes, and is attached to the under surface of the penis and to the raphe. Give the fasciae within the scrotum. The intercolumnar fascia, separated by loose areolar tissue from the dartos, is attached to and descends from the margins of the pillars of the external ring. The cremasteric fascia consists of scattered muscular loops or bundles (crem aster muscle), connected together by areolar tissue, the former being continuous with the lower border of the internal oblique. The infundibuliform fascia is continuous above with the fascia trans- 346 ORGANS OF REPRODUCTION (mALE). versalis and the subserous areolar tissue of the peritoneum. These two together, the latter being underneath, form the fascia propria. It in- vests the surface of the cord and sends in septa between its component parts. The tunica vaginalis (see Testicle proper). Describe the testicle proper and epididymis. ^ Each testicle is ovoid, flattened from side to side, and suspended ob- liquely (the left being somewhat the lower), its upper end being directed forward, outward, and upward, the lower in the opposite direction. •Each is IJ inches long, \\ inches wide, and less than 1 inch thick, and weighs i to 1 ounce. The front, sides, and both ends of the testis are free, smooth, and covered by the tunica vaginalis. At the posterior border the vessels and nerves enter and emerge, and to this border, as well as to the outer sur- face, is attached the epididymis. The epididymis is' a long, narrow structure, made up of a hody^ a head or globus major^ and a tail or globus minor. The globus major is large, and joined to the upper end of the testicle by the efl'erent ducts ; the minor is small and pointed, and is joined to the lower end of the testicle by a reflection of the tunica vaginalis and some cellular tissue. The convex surface and anterior border of the epididymis are free and covered by the tunica vaginalis, as is also the concave or attached surface (except at the ends), the serous membrane here forming the digital fossa. On the front oi the globus major are one or more small pedunculated bodies called the hydatids of Morgagni, believed to be the remains of Miiller's duct. The epididymis is a con- voluted canal whose lumen is continuous with that of the vas deferens. The tunica vaginalis is a closed serous sac, and consists of a vis- ceral layer and a parietal layer. The visceral layer adheres to the outer surface of the tunica albuginea, suiTounding the testis and epididymis, and joining them together by a fold. It forms between them the pouch known as the digital fossa. The parietal layer is reflected on to the inner surface of the scrotum at the posterior border of the testicle. The tunica albuginea is the fibrous coat which surrounds the soft substance of the testis and is reflected at the posterior border into its in- terior, forming a sort of septum, the corpus Highmori or mediastimmi testis. This septum, wider above than below, extends from the upper nearly to the lower end of the gland, and sends off" numerous trabeculae which join the inner surface of the tunica albuginea. These divide the organ incompletely into lobules. The tunica vascuJosa (pia mater testis) is a vascular plexus supported by areolar tissue which covers the inner surface of the tunica albuginea and its trabeculae. The gland substance consists of seminiferous tuhules, which are contained within the lobules above mentioned, each lobule containing two THE TESTES. 347 or three seminiferous tubules. Each of these latter is lined by several layers of epithelial cells, from which, by a process of division (karyoki- nesis), are finally developed the spermatozoa. The lobules are conical, their bases being turned toward the circum- ference, their apices toward the mediastinum. In the latter situation the tubules become straighter, and unite to form twenty to thirty large ducts, the tuhuli recti These tuhuli recti open into a vascular network, the rete testis, which lies in the substance of the mediastinum, and from this issue twelve to twenty vasa efferentia, which pierce the tunica albu- ginea and enter the globus major of the epididymis, where they now become tortuous and form conical masses, the cojii vasculosL Describe the vas deferens, the vesiculse seminales, and the ejac- ulatory ducts. The vas deferens, the continuation of the epididymis, is the excre- tory duct of the testicle. From the globus minor it runs along the inner side of the epididymis and back of the testis, and in the spermatic cord to the internal ring : here it descends, crossing the external iliac vessels, and curving around the outer side of the deep epigastric artery. It now passes beneath the peritoneum to the side of the bladder, and runs down- ward and backward to its base, internal to the ureter and across the ob- literated hypogastric artery. At the base of the bladder it lies between it and the rectum, internal to the seminal vesicle, the duct of which it joins (close to the base of the prostate) after having enlarged and again narrowed, forming with it the ejaculatory duct. Its length is about 2 feet and its diameter about ^ inch. It has an external areolar coat, a middle muscular coat of two layers, longitudinal and circular, and an internal mucous coat covered with columnar epithelium. The vesiculse seminales, conical in form, the wider end looking backward, lie between the rectum and the base of the bladder, and are the reservoirs for the semen. They are 2 inches long and i inch wide. In front they converge, and each joins the corresponding vas deferens at the base of the prostate to form the ejaculatory duct. The vesicle is a single tube 4 to 6 inches long, coiled up and giving ofi* diverticula. It ends behind in a blind extremity, and is 2 inches long in its natural con- dition. Each ejaculatory duct is f inch long, and runs one on each side, forward and upward within the prostate, between its middle and lateral lobes, and along the walls of the sinus pocularis, close to the opening of which they empty. Each has an areolar, a muscular, and a mucous coat. The semen is a whitish fluid composed of liquor seminis, seminal Granules, and spermatozoa. The granules are ^oo inch in diameter, 'he spermatozoa consist of a head, formerly the nucleus of a spermato- blast, a body, and a tail. The spermatoblasts constitute one of the layers of epithelial cells lining the seminiferous tubules. 348 ORGANS OF REPRODUCTION (fEMALE). ORGANS OF REPRODUOTION (FEMALE). External. THE VULVA. Describe the vulva. The term vulva or pudendum includes the mons veneris and labia, the nymphae and clitoris, the hymen or its remains, the meatus urinarius, and the vaginal orifice. Describe these various parts. The mons veneris is a fatty cushion covering the front of the pubes, and after puberty is plentifully supplied with hairs. Below, it divides into the two labia majora, which, diminishing in size as they pass downward and backward, unite an inch in front of the anus. The two extremities are joined, and form the anterior and posterior commissures. Between the latter and the anus is the perineum, and just within the posterior commissure is a transverse fold, the fraenulum pudendi or fourchette. Between this fold and the posterior commissure is a triangular space, the fossa navicularis. The nymphce^ or labia minora, smaller than the above, run from the middle of the labia majora upward to the clitoris, each dividing into two folds, the upper pair of which join to form a prepuce for that organ, and the lower two to form its fraenum. They are continuous externally with the labia majora, internally with the vagina. The mons veneris is composed interiorly of fatty and fibrous tissue ; the labia, of areolar fatty and dartoid tissue, with vessels and nerves ; the nymphae, of a plexus of vessels covered by mucous membrane. The clitoris is the analogue of the penis, consisting like it of two corpora cavernosa united by a septum pectiniforme, and prolonged behind into two crura attached to the pubic and ischial rami. It also has a sus- pensory ligament and a glans enclosed by the nymphae. Two erectores clitoridis muscles are attached to the crura. It has no corpus spongiosum nor urethra. Between the clitoris and the vagina, bounded on each side by the nymphae, is the vestibule,^ a triangular space, in which, just above the vagina, is the meatus urinarius, 1 inch below the clitoris. The hymen is a mucous fold which more or less completely occludes the orificium vaginae. It is generally semilunar in form, concave above, or it may be a complete^ membrane, perforate or imperforate, or it may be absent. After labor its remains form the carunculae myrtiformes. The glands of Bartholin^ the analogues of Cowper's glands in the male, are two yellowish bodies on each side of the vaginal opening, each of which discharges by a single duct between the hymen and the nymphae. On each side of the vestible, behind the nymphae, is a leech-shaped mass, the hulhus vestibidi Each consists of a venous plexus enclosed THE UKETHRA. — THE UTERUS. 349 by a fibrous capsule, and is about 1 inch long. In front of these, and connecting them with the vessels of the clitoris, is a small venous plexus, . the pars intermedia of Kobelt. THE URETHRA. Describe the urethra. The female urethra is a mucous canal, H inches long, running down- ward and forward in the anterior vaginal wall from the neck of the bladder to the meatus. As in the male, it pierces the triangular liga- ment, and is surrounded by the compressor urethrse muscle. It consists of a muscular, a mucous, and, between them, an erectile, coat. It is supplied with numerous glands,, and just within the meatus near the floor are two ducts which extend upward for about f inch. These are called Skene's tubules. THE VAGINA. Describe the vagina. The vagina extends from the vulva to^ the uterus, lying behind the bladder and in front of the rectum, and is about 4 inches long on its anterior wall, 5 to 5 J on its posterior, and is directed from the uterus downward and forward. Above, it embraces the cervix uteri, and its walls are flattened from before backward. It is narrowest at the introitus, or orificium vaginge. Li front it is in relation with the urethra and base of the bladder; behind it is connected with the anterior wall of the rectum by its lower three-fourths, the cul-de-sac of peritoneum (Douglas's) separating them above ; laterally the broad ligaments are attached above, and the leva- tores ani below, as well as the recto-vesical fascia. Its inner surface pre- sents a mesial ridge or raphe on the front and back walls, the columuse ru^arum, and from them on both sides run out transverse folds or rugae. The vaginal mucous membrane is squamous, with papillae here and there. The submucous coat holds many large veins and some muscular fibres, making a sort of erectile tissue. The veins form a sort of plexus. The muscular coat comprises an internal circular and an external longi- tudinal layer. At the lower part is the sphincter vaginae, a muscle composed of striped fibres. The internal organs include the uterus^ tubes, and ovaries. Internal. THE UTERUS. Describe the uterus. The uterus or womb is a hollow muscular organ lying in the pelvis between the bladder and rectum. In the virgin it is pear-shaped, flattened from before backward, its upper end looking forward and up- ward, its lower downward and backward, forming an angle with the 350 ORGANS OF REPRODUCTION (fEMALE). vagina. Above, it is invested by the peritoneum, which covers its body before and behind ; it covers also the cervix behind, but in front the peritoneum is reflected on to the bladder before reaching the cervix. . Its upper and back part is in contact with the small intestine, its lower and front part with the bladder, the peritoneum separating them. The two folds of peritoneum after investing the uterus are applied to each other and form the broad ligaments. The uterus is 3 inches long, 2 wide, and 1 thick, and it weighs about 1 ounce. It is divided into a body, fundus, and neck. The fundus is the convex part above the entrance of the tubes ; the body is the part between this and the neck. In fi'ont of the Fallopian tubes, at the up- per part of the lateral borders, the round ligaments are attached, and below and behind them are the ligamenta ovarica. The cervix is the lower constricted, rounded part, and around it is attached the vagina. At its vaginal end is a transverse opening, the os uteri, the posterior lip of which is thin and long, the anterior thick. Describe the cavity of the uterus. The cavity of the uterus is small ; that part within the body is tri- angular, flattened antero-posteriorly, and presents at the superior angles the openings of the Fallopian tubes ; also, at its junction with the neck it is constricted to form the os internum or isthmus. The cavity of the cervix is barrel-shaped and flattened antero-posteriorly, presenting on each wall a longitudinal column sending ofi" oblique rugae on each side ; hence its name, arbor-vitae uterinus. Give the structure of the walls of the uterus. The walls of the uterus consist of an outer serous coat (already de- scribed), an inner mucous, and an intermediate muscular. The muscular coat forms the bulk of the uterus, and consists of bundles and layers of unstriped fibres which interlace, and of some areolar tissue supporting them, and of blood-vessels, lymphatics, and nerves. Three laj^ers are described — an external transverse layer, some of the fibres being con- tinued on to the Fallopian tubes, etc. ; a middle layer of intermixed longitudinal, oblique, and transverse fibres ; and an internal layer, which is circularly arranged at the cervix, forming the so-called external and internal sphincters. This layer is the muscularis mucosae of the mucous membrane. Describe the mucous membrane of the uterus. The mucous membrane of the body differs from that of the cervix. The former is smooth, reddish, with columnar cells, and presents the ducts of a number of tubular glands which end by blind, sometimes forked, extremities. In the cervix it is firmer, and presents numerous saccular and tubular glands between the rugae of the arbor vitae, and, below, numerous papillae. The glands are sometimes distended by their secretion, the ducts being choked, and present the appearance of vesi- PLATE XXXI. Fig. 1. — To face pages 349 and 350. Antero-posterior (sagittal) Section of the Pelvic Organs of a Virgin : Ijjvagina ; 2, uterus ; 3, posterior lip ; 4, anterior lip ; 5, anus ; 6, perineum ; 7, symphysis pubis ; 8, fimbriated extremity of the Fallopian tube ; 9, the €mpty bladder — note its Y shape, and also that the walls of the uterus, vagina, urethra, and bladder are in contact except when distended by their appropriate contents (D. Berry Hart). PLATE XXXII. Fig. 1 . — To face page 351, Posterior View of Uterine Appendages : 1, uterus ; 2, Fallopian tube ; 3, fimbriated extremity and opening of the Fallopian tube ; 4, epooplioron ; 5, ovary ; 6, ligament ; 7, ligament of the ovary ; 8, infundibulo-pelvic (broad) ligament (Henle). THE FALLOPIAN TUBES. — THE OVAKIES. 351 cles ; hence their name, ovules of Naboth. At the upper part of the cervix the cells are columnar and ciliated; below, stratified. What are the ligaments of the uterus ? The ligaments of the uterus are the round ligaments and several peritoneal folds — namely, two each in front, behind, and laterally. The round ligaments are two cord-like bundles of areolar, fibrous, and plain muscular tissue, with vessels and nerves, covered by peritoneum, which run from the upper angle of the uterus to the internal ring. Each then runs through the corresponding inguinal canal to end in the mons veneris and labia. Each measures about 4 or 5 inches in length, and their direction is upward, forward, and outward. The peritoneum, which invests them, is sometimes prolonged (as in the foetus) for some distance into the inguinal canal, and forms the canal of Nuck. Gene- rally this canal is obliterated. The anterior or vesico-uterine ligaments stretch between the bladder and the uterus ; the posterior, between the uterus and rectum, hence called the recto-uterine^ forming a pouch, the cul-de-sac of Douglas. The two lateral or broad ligaments pass from the sides of the uterus to the sides of the pelvis, thus dividing the latter into two parts. They are formed by the coalescence of the peritoneal layers investing the ante- rior and posterior surfaces of the uterus, and contain between the two layers : the Fallopian tube at the upper margin ; the round ligament be- low and in front of the tube ; the ovary and its ligament enfolded by the posterior layer ; and the uterine blood-vessels, lymphatics, and nerves. THE FALLOPIAN TUBES. Describe the Fallopian tubes. The Fallopian tubes, or oviducts, run from the upper angles of the uterus toward the sides of the pelvis, and near their termination bend downward, backward, and inward. They are 3 to 4 inches long, are at first narrow, then enlarge near the extremity (ampulla), and end in a fimbriated margin, one of the fimbriae being attached to the ovary. The canal is very narrow at the uterine end (ostium uterinum), begins to widen in the outer half to form the ampulla, and at its termination again narrows (ostium abdominale). The tubes consist of a peritoneal coat, a muscular coat composed of internal circular and external longitudinal fibres, and a mucous coat. The latter is continuous with that of .the uterus and with the perito- neum, the epithelium being ciliated columnar, and it is thrown into lon- gitudinal wrinkles, more marked in the outer half of the tube. THE OVARIES. Describe the ovaries. The ovaries are analogous to the testes, and are flattened, oval bodies, measuring IJ inches long, | inch wide, and J inch thick, each weighing 352 ORGAJsrs of reproduction (female). 60 to 100 grains. Of each, the two sides are free as well as the convex border, the straight border (hilus) being attached to the broad Hgament and admitting the vessels, etc. Its outer end is attached by the fimbria ovarica to the Fallopian tube, its inner end to the uterus by the ligament of the ovary, a dense, fibro-muscular cord attached to the uterus below and behind the tube. The ovary consists of a stroma in which are imbedded the Graafian follicles, and of a covering of columnar cells, the germinal epithelium. The stroma is invested beneath the epithelium by a dense fibrous layer, the tunica albuginea, and consists of connective tissue with numerous cells, as well as of elastic fibres, with some muscular tissue and blood- vessels. The Graafian follicles consist of an external fibrous coat, and beneath it a coat called the ovi-capsule, lined internally by a layer of cells, the memhrana granulosa. Within this last-named layer is the ovum, in- vested by the discus proligerus, a layer of cells derived from the mem- brana granulosa, together with the liquor foUiculi. For the structure of the ovum see Histology ^ or Gynecology . or Ob- stetrics of this series. THE PAROVARIUM. What is the parovarium ? The parovarium, organ of Eosenmiiller, is a foetal remnant lying in the broad ligament between the ovary and Fallopian tube. It consists of several vertical tubes, lined by epithelium, whose lower ends run toward the hilus of the ovary, and whose upper ends are united by a horizontal tube, the duct of Gaertner. THE MAMMARY GLANDS. Describe the mammary glands. These are accessory to the generative system and secrete the milk. They are two rounded eminences, one on each side of the thorax, between the sternum and axilla and the third and seventh ribs. Just below the centre is a conical eminence, the nipple, which is dark, and is surrounded by a pinkish areola which darkens in pregnancy. ^ It presents the orifices of the lactiferous ducts, and consists of vessels mixed in with plain mus- cular fibres, and by friction may be made to undergo erection. The mamma consists of a number of lobes separated by fibrous tissue and some adipose tissue. The lobes are divided and subdivided into smaller lobules, which are in turn made up of alveoli. ^ Each lobe has an excretory (galactophorous) duct, and these, about sixteen in number, converge to the areola, there dilating into ampulla' or sinuses. They then become smaller again, and, surrounded by areolar tissue and ves- sels, pass through the nipple to empty on the surface by separate orifices. GLOSSARY. F. = French ; Gr. = Greek ; L. = Latin ; N. L. = New Latin ; adj. = adjective ; c. = common ; dim. = diminutive ; f. = feminine ; m. = masculine ; n. = neuter or noun; part. = participle. Abdo'men, inis, n. (L.) = venter. [Etymology doubtful. Andrews: Adipomen, from adeps, fat, lard, the fat lower part of the belly ; Foster : Abdere, to conceal, and omen, either a sign in ancient augury or a contr. of omentum — that which conceals the omen or omentum. This explanation of omen does not commend itself; men is a formative ending, the w^hole word meaning '' the concealer."] The belly, paunch. Acerv'ulus, i, m. (L.) (aserv'ulus) [dim. of dcervus, i, m., a heap ; root aJc, per- haps related to agitare, to drive]. A little heap; applied to a collection of "brain-sand" in the pineal gland. Acetab'ulum, i, n. (L.) [^ace'tum, vinegar]. A vinegar vessel, hence any cup- shaped vessel. The articular cavity of the innominate bone. Adminic'ulum, i, n. (L.) \^ad, manus, upon the hand]. The stake around which the vine twines. A support. Afferent [aff evens, part, from ad, to, ferre, to carry]. Conveying something from the periphery to the centre. Ag'ger, eris, m. (L.) [aggerare, to heap up]. A heap or prominence. Alve^olar (not alveolar). Pertaining to or containing alveoli. Alve'olus, i, m. (L.) [dim. of alv^us, a hollow]. Bone-socket for a tooth ; an air-cell ; a part of a gland. Anarogous [avd, \6yog, according to due ratio]. Referring to a part in one organism which has the same function as another part in another organ- ism; similarity of purpose. " When organs in different animals agree in structure they are ' homologous ;' when they perform the same functions, they are ' analogous.' The wing of a bird and arm of a man are homolo- gous, not analogous ; the wing of a bird and the wing of an insect are analogous, not homologous." Anas'tomo'sis, is, f. (L.) [avd, of each, o-tojuow, to furnish with a mouth, to contract to a narrow mouth, to whet the appetite]. The communication of an artery or vein with another artery or vein. Anat'omy [dvd, apart, refiveiv, to cut]. A science of the structure of organized bodies. Anco'neus, a, um, adj. or n. m. (L.) [ancon, onis, m.. = dyKU}v, the bend of the arm]. Any muscle connected in any way with the olecranon ; now applied to one muscle connected with the triceps and olecranon. Annec'tant [annecto, ad, to, necto, I fasten together]. Connecting. Applied to brain-tissue that connects adjacent gyri. Anti'cus, a, um, adj. (not an'ticus) (L.) [ante, before]. Anterior. Aor'ta, ae, f. (L.) [acpr^, in Hippocrates the bronchi; from aetpw, I lift or heave]. The common trunk of the systemic arteries. Apoph'ysis, is, pi. as, f. (L.) (apof isis) [dirocfyvui]. An outgrowth. Aq'ueduct (L. aquxductus, us, m.) [aqua, water, ducere, to lead]. A canal; it may or may not contain fluid. 23— A. 353 354 GLOSSARY. Arach'noid, adj. and n. (arak^noid) (L. arachnoid^ etis) [apdxvri, a spider's web, et5o9, resemblance]. The middle of the three membranes investing the brain and spinal cord. Are'olar (not areo'lar) [dre^^la, se, f. dim. of area, an open space]. Pertaining to a tissue containing interspaces. Ar'tery (L. arte'ria, se, f. Gr. aprrjpca) [from dpTJjp, that which suspends; origi- nally applied to the trachea, called the "rough artery," rpax^la apr-npia, suspending the lungs ; perhaps from arip, ae'pos, air, TTjpe'w, 1 convey. The ancients believed it contained air, being found empty after death]. A vessel which conveys blood from the heart. Aryte'noid (L. arytsenoid'eus, from arytse'na) [dpuTatva, a ladle or pitcher, ei5os, resemblance]. Shaped like the mouth of a pitcher. A cartilage of the larynx. Aste'rion, ii, n. (L.) [do-r^p, star]. A sort of spider ; point of junction of pari- etal, occipital, and temporal bones. Astrag'aliis, i, m. (L.) [do-rpdYaAos, a cervical vertebra; do-TpdyaXot were dice made of the cubical ankle-bones; Lat. tali were stone dice]. The ankle- or sling-bone, the first of the tarsus. Az'ygos, n. and adj. [d, without, ^vyov, yoke]. Without a fellow; unyoked. Basiric [L. basiVicus ; Gr. paaLkiK6> to mark with xl- The crucial union of parts. Circumvallate [dream, around, vallare, to surround with a rampart]. Sur- rounded with a prominence. Cli'toris (not klit'oris), clitor'idis, f. (L.) [/cAeiropt?, KAeiropt^eti/, to titillate, or from K\eULv, to shut up, or from kAtjtj^p, a servant who invites guests]. A small erectile organ in the vulva, homologue of the penis. Coccygeal (koksij'eal, not koksige'al) (L. coccyg'eus). Pertaining to the coc- cyx or tail. Coc'cyx (kok'siks), gen. coccy'gis (not coc'cygis) (L.) [kokkv^, a cuckoo, whose beak it resembles]. The caudal end of the spinal column. Coe'liac (see'liak) [/cotAta/cos from /coiAta, the belly]. Eelating to the abdomen or its viscera. Com'es, com'itis, m. or f. (L) {cum, with, eo, I go]. A companion. Con'dyle, L. condylus, i, m. (con'dil) [k6v8v\o^, a knot]. An articular process. Con'jugal [conjux, %is, c. spouse ; con, together, jimgfo, to yoke]. Lig. conju- gale, united with its fellow. Conniven'tes, adj. pi. (L.) [coimivens entis, from con-niveo, I wink]. Folding on each other {valvulse c). Coro'nal (not cor'onal) [coro'na, se, f. Koptavn], crown]. Relating to a crown. Cran'ium, ii, n. (L.) [/cpavo?, helmet, or from Kpaviov, skull]. The brain-case; the entire skull. Cremas'ter, cremaster'is, m. (L.) [/cpeju.as piece, a coin ; as was a pound weight, or 16'i cents. As the Roman numeral on the coin was X, decussis came to mean the intersection of two lines]. To cross ; to place in the form of an X. Di'aphragm [dy'afram), L. diapliragma, atis, n. (dyafrag'ma) [Sta^pav/xa, a partition-wall ; 6ta, thoroughly, ^pao-o-w, I fence in]. A partition between cavities. The partition between the thoracic and abdominal cavities. Diaph'ysis, is, f. (diaf isis) (L.) [5ta, between, (f>v€tv, to grow]. The part of bone formed from the principal centre. Digas'tric [8Cs, twice, yaa-rrip, belly; L. biventer]. Having two bellies. Duode'nuin, i, m. (L.) [duodeni, twelve each]. Upper portion of the small intestine, about 12 finger-breadths (10 inches) long. Efferent [effei-ens, part., ex, from, fer re, to carry]. Carrying or leading from an organ. Em'bryo, o'nis (L.) [efi^pvov, eV, within, /Spvw, to be full of anything]. The fecundated ovum in the first two or three months of its development. (See FcETUS.) Em'issary [e, out, mittere, to send]. Serving as an outlet. Ephip'pium (effip'pium)), ephip'pii, n. (L.) [ini, upon, 'imro^, horse]. A sad- dle ; a part of the sphenoid bone. Epiph'ysis (epifisis), is, f., pi. Epiph'yses (L.) [ini, upon, v€Lv, to grow]. The portion of a long bone from a secondary or tertiary centre. 356 GLOSSARY. Epiplo'ic (L. epiplo'icus, a, urn, adj.) [en-tTrAooi', omentum, ctti, upon, TrAe'co, I float]. Pertaining to the omentum. Epipter'ic (epipter'ik) [eTrt, upon, -nTepov, wing]. Situated on the greater wing of the sphenoid. Eustach'ius (Bartholomeo Eustachi), of the Italian school (1500), was the con- temporary of Vesalius, and divides with him the merit of creating the science of anatomy. He studied especially the internal ear. Exore'tory \^ex, out, cerno, I choose]. Pertaining to excretion (the separation from the body of parts supposed to be useless). Fac'et (not faset') (F.) [dim. of /ace]. A small face. Fallopius was a pupil of Vesalius, and professor at Padua in 1551 ; studied bones,^especially the internal ear and organs of generation. Ferrugin'eus, a, um, adj. (L.); also ferrug'inus [ferriigo, iron-rust, from fer- rum, iron]. Of the color of iron-rust; dusky. Foetus, lis, m. (strictly fetus) (L.) [from root feo, whence also fecundus and felix, fruitful ; femina, fruit-bearer ; fenus, interest or gain]. The unborn child. In the human subject this term is usually applied to the embryo only after the third month of gestation. Fontanelle (fontanel') (F.) [fontanella, se, t, dim. of fons, fontis, a fountain]. A membranous interspace between foetal skull-bones. Pulsation like a fountain is here seen. Fo'vea, ae, f. (L.) [fodio, ere, to dig]. A small pit, a pitfall. An old term for the vulva. Gal'ea, ae, f. (L.) [yaAeTj, weasel, from the skin of which helmets were made]. Helmet ; the amnion. Ga'len, L. Claudius Galenus \ya\av6<;, calm]. The greatest anatomist of antiq- uity, lived in Pergamus and Eome; died, set. 90, in 193 a.d. Wrote in Greek ; he described the bones and sutures of the cranium, the vertebrae, the thorax, nearly in the same manner as at present. He described the facial, maxillary, and neck muscles, naming one the platysma myoides. He proved that arteries contained blood, not air. His death marked the downfall of ancient anatomy. Gallinag'o, gallinaglnis, f. (L.) [gallVna, ss, hen]. The wood-cock. Caput gal., syn. of verumontanum. Glabel'la, ae, f. (L.) [glahellus, a, um, dim. of glaber, smooth, without hair]. The part of the frontal bone between the superciliary ridges. Glans, glandis, f. (L.). An acorn. Any object resembling a nut, as the head of the penis or clitoris, a suppository, a pessary, a goitre. Hal'lex, hal'licis, or allex, alUcis, m. (L.) [aWoixai, to leap]. The great toe or thumb. (There is no authority for hallux, hallucis ; hallus or alius, kindr. with allex, has the gen. alii. Alex, alecis, f. and m., fish-brine or sedi- ment.) Belicotre'ma, helicotre'matis, n. (L.) [e'Aif, helix, spiral, TpTiixa, hole]. An aperture at the apex of the cochlea. Hemorrhoid'al [hsemor'rho'is, idis, f., alfioppot^, usually in pi. supply ^9, distinct, manifest]. Applied to some superficial veins of the lower extremity, to nerves, and to an " opening." Scala, ae, f. (L.) [scando, h^e, I climb]. A staircase; a ladder. Scanso'rius, a, um, adj. (L.) [scando, scansum, I climb]. Of or for /ilimbing. Sciat'ic (syat'ik) (contraction of ischiatic) [lax^ov, strictly the acetabulum; the haunch or hip. Prob. from io-xv?, strength]. Eelated to or connected with the ischium. Secre'tory [se, aside, cerno, I choose or put]. Pertaining to secretion (the sepa- ration from the blood of parts supposed to be useful to the animal economy). Sinister, tra, trum, adj. (L.) (obs. sinis'ter). On the left hand ; left. (In the Roman sense lucky ; in the Greek sense unluclcy. In consulting aus- pices the Eomans turned the face to the south, and so had the eastern or fortunate side to the left ; while the Greeks, turning to the north, had it on their right.) SoPeus, i, m. (L.) [soUa, se, f., the sole of a shoe, sandal]. A muscle of the calf of the leg ; named from its shape. Somat'opleure [aSifxa, body, -rrkevpa, a rib, the side, lining membrane of the chest]. Outer leaf of blastoderm, producing the body- walls. So^mites (L.) (L. pronunc. so'mi tes) [aiafxa, o-w/uaTos, body]. Segments of the body or mesoderm. SplanchnoPogy [a-irKdyxvov, pi. a, viscera, A.6yos, treatise]. The part of anatomy relating to viscera. Splanch'nopleure [a-TrXdyxvov, viscera, inward parts, TrAeupa, the pleura]. Inner _leaf of the blastoderm, forming the alimentary canal. Sple'nic [splen, splenis, m., also lien, enis, m. ; a-n\riv, jjro?, the milt, spleen]. _Relating to the spleen. Sple'nium, ii, n. (L.) [o-ttA^j', spleen]. A patch, pad (because like the spleen in shape). Sple'nius, a, um, adj. or n. (L.) [(rnKrjvLov, a bandage, compress; . Dartos, 145 Deglutition, 164 Development of ovum, 17 Diaphragm, 152 Diarthrodial joints 93, 94 Duodenum, 325 Dura mater, 249, 252 E. Ear, 301 Elbow-joint, 110 Embryology, 17 Eminence, deltoid, 68 frontal, 38 nasal, 38 hypothenar, 184 thenar, 184 ilio-pectineal, 77 olivary, 44 Eminentia arcnata, 42 articular is, 39 capitata, 71 cinerea, 265 collateralis, 259, 260 innominata, 36 Epiblast, 17, 18 Epididymis, 346 Epiphysis, 20 cerebri, 262 Eustachian tube, 43, 302 valve, 205 Eye, 297 F. Fallopian tubes, 351 Fascia, 139 anal, 150 axillary, 154 bucco-pharyngeal, 162 Buck's, 149 cervical, 157 cremasteric, 148 Fascia dentata, 260 iliac, 148 infundibuliform, 148 intercolumnar, 147 lata, 186 lumbar, 142 masseteric, 171 obturator, 150 of abdomen, 145, 148 of arm, 174 of breast, 154 of Colles, 149 of forearm, 176 of pelvis, 150 of Scarpa, 145 palmar, 183 parotid, 158 perineal, 149 plantar, 198 prevertebral, 158 recto- vesical, 150 semilunar, 175 subpubic, 149 temporal, 172 transversalis, 148 Fasciculus teres, 265 Fat-pad, buccal, 171 Fissure, calcarine, 256 calloso-marginal, 256 collateral, 257 dentate, 256 hippocampal, 256 longitudinal, 257 of Glaser, 40 of Eolando, 255 of Sylvius, 255 parietal, 62 parieto-occipital, 257 petro-squamous, 40 precentral,255 pterygo-maxillary, 58 sphenoidal, 46, 57 spheno-maxillary, 57 Flocculus. 263 Fontanelle, 62 Foramen, aortic, 153 csecum, 39 carotico-clinoid, 47 carotico-tympanicus, 43 centrale cochleae, 42 condylar, 36 inferior dental, 55 infraorbital, 48, 49 intervertebral, 24, 30 .; INDEX. 365 Foramen, Jacobson's, 43 jugular, 37 lacerum, 59 mastoid, 40 mental, 54 obturator, 77, 79 of Magendie, 253 of Monro, 259, 261 of Vesalius, 47 optic, 44, 46, 57 ovale, 46 parietal, 37 quadratum, 153 rotundum, 45, 46 sacral, 28 singulare, 42 spinosum, 46 sternal, 32 stylo-mastoid, 43 supratrochlear, 69 thyroid, 77, 79 Foramina, incisor, 49 of Scarpa, 49 of Stenson, 49 Thebesii, 205 Fornix, 261 Fossa acetabuli, 79 anterior palatine, 49, 58 canine, 48 condylar, 36 coronoid, 69 digastric, 40 digital, 81 glenoid, 40, 67 guttural, 58 hypo-trochanterica, 83 iliac, 77 incisor, 48, 54 infraspinous, 66 infratemporal, 58 intercondylar, 82 jugular, 43 lachrymal, 38, 57 mandibularis, 40 myrtiform, 48 nasal, 60, 308 olecranon, 69 ovalis, 205 pituitary, 44 pterygoid, 46 radial, 69 scaphoid, 46 sigmoidea, 41 spheno-maxillary, 58 Fossa, subarcuate, 42 subscapular, 65 supraspinous, 66 temporal, 57 trochlear, 38 zygomatic, 58 Funiculus of Eolando, 253 cuneatus, 253 gracilis, 253 G. Galea aponeurotica, 166 Gall-bladder, 333 Ganglion, cervical, 292, 293 Gasserian, 267 geniculate, 272 jugular, 274 Meckel's, 269 ophthalmic, 268 otic, 271 petrous, 274 semilunar, 295 submaxillary, 271 Geniculate bodies, 262 Gerdy's fibres, 183 Glabella, 38 Gland, mammary, 352 parotid, 321 prostate, 342 sublingual, 321 submaxillary, 321 thymus, 315 thyroid, 315 Groove, basilar, 37 bicipital, 68 infraorbital, 49 lachrymal, 49 mylo-hyoid, 55 obturator, 78 olfactory, 48 optic, 44 posterior palatine, 51 spiral, 68 subcostal, 33 Gyrus, angular, 256 fornicatus, 257 hippocampi, 257 marginal, 256 opertus, 256 uncinate, 257 H. Heart, 204 366 INDEX. Heiniarthrosis, 94 Henle's ankle-joint, 133 classification of joints, 94 vertebral ligaments, 100 wrist-joint, 114 Hip-joint, 123 Hippocampus, 259, 260 Homologies, muscular, 202 of carpus and tarsus, 92 of ilium and scapula, 92 of upper and lower limbs, 91 Hypoblast, 17, 18 Hypophysis cerebri, 258 Ilio-tibial band, 186 Index, humero-radial, 72 of cranium, 64 sacral 29 Infundibulum, 47, 258, 306 Inion, 64 Intervertebral disks, 96 Intestines, 324 Iris 299 Island of Reil, 256 Joints, classification of, 93 K. Kidney, 336 Knee-joint, 125 L, Labyrinth, 47, 305, 306 Lacertus fibrosus, 175 Lambda, 63. Lamina cinerea, 257 cribrosa, 42 papyracea, 47 Larrey's space, 153 Larynx, 310 Ligament or Ligaments, accessory, 95 of astragalus, 135 of foregirm, 113 of hip, 154 of knee, 128 of tarsus, 136 of wrist, 116 tibio-fibular, 134 Ligament or Ligaments, accessorium laterale, 103, 129 mediale, 103, 129 radiale, 119 ulnare, 119 acromio-clavicular, 106 alar, 99, 127 annular, 116, 194 anterior, 95, 110, 114, 128, 132 arcuate, 118, 121, 128, 153 astragalo-scaphoid, 133 atlo-axoid, 98 Bertini, 124 brachial, 174 calcaneo-astragaloid, 133 calcaneo-cuboid, 133, 136 calcaneo-fibulare, 136 calcaneo-naviculare, 136, 137 calcaneo scaphoid, 133, 136 calcaneo-tibiale, 136 capituli fibulae, 131, 132 capitulorum, 138 dorsalia, 120 volaria, 119 capsular of elbow, 110 of hip, 123 of knee, 127 of lower jaw, 103 of shoulder, 107 of vertebrae, 96 of wrist, 115 carpi commune, 116 dorsale profundum, 117 volare profundum, 118 proprium, 117 carpo-metacarpea, 117 chondro-sternal, 101 chondro-xiphoid, 102 colli costse, 101 conjugal, 100 conoid, 107 coraco-acromial, 104 coraco-clavicular, 107 coraco-glenoidale, 109 coraco-humeral, 109 coronary, 126 corruscans, 102 costo-clavicular, 106 costo-coracoid, 154 costo-transverse, 100, 101 costo- vertebral, 99, 100 cotyloid, 123 crucial, 98, 126, 194 cuboideo-naviculare, 137 INDEX. 367 Ligament or Ligaments, cuneo-cu- boidea, 136 deltoid, 132 denticulatum, 249 dorsal, 114, 119, 120, 133 falciform, 122 Flood's, 109 fundiform of Retzius, 194 Gimbernat's, 147 reflected, 147 <;lenoid, 108 glenoideo-brachial, 109 glenoideo-liumeral, 109 hamo-metacarpeum, 119 humero-coronoid, 111 humero-olecrauon, 111 iliacum proprium, 120 ilio-femorai, 124 ilio-lumbar, 121 ilio-pectiueal, 149 ilio-trochanteric, 124 inguinal, 147, 149 interarticular, 100 fibro-cartilage, 103, 106 intercarpea, 117 interchondral, 102 interclavicular, 106 intercostal, 102 intercruralia, 101 intermetacarpea, 117, 119 intermetatarsea, 136, 137 intermuscularia, 174 interosseous, 113, 114, 132, 133 interspinous, 96 intersternal, 102 intertransverse, 97 intrajugular, 103 ischio-capsular, 124 iscliio-femoral, 124 laciniatum, 194 lateral, 99, 103, 111, 113, 129, 132 latum, 99 iumbo-costal, 101 malleoli lateralis, 134 metatarsal, 133 metatarso-phalangeal, 138. mucosum, 115, 127, 179 naviculari cuboidea, 136 nuchse, 96 oblique, 113, 128 obturator, 98, 120 occipito-atloid, 98, 99 occipito-axoid, 99 odontoid, 99 Ligament or Ligaments of ankle- joint, 132 of Barkow, 111 of Bigelow, 124 of bladder, 150 of Burns, 187 of carpus, 114 of ilio-sacral joint, 121 of Colles, 147 of elbow-joint, 110 of Hey, 187 of hip-joint, 123 of knee-joint, 125 of larynx, 311 of metacarpus, 114 of phalanges, 114, 133 of rectum, 150 of scapula, 104 of shoulder-joint, 107 of skull, 102 of tarsus, 132, 136 of uterus, 351 of Winslow, 128 of wrist-joint, 113 of Zinn, 170 olecrano-coronoid, 111 orbicular, 111, 124 palmar, 114 palpebral, 167 patellae, 128 petro-sphenoidal, 43, 103 piso-hamatum, 119 piso-metacarpeum, 119 plantar, 133 plicse synov. patellaris, 127 popliteum arcuatum, 128 posterior, 95. Ill, 114, 128, 132 Poupart's, 146 pterygo-maxillary, 104 pterygo-petrosal, 103 pubo-femoral, 124 pubo-prostatic, 150 radiate, 118 radio-ulnar, 113 retinacula tendinum, 120 retinaculum, 109 lig. arcuati, 128 peronseorum, 194, 196 sacro-coccygeum articulare, 97 sacro-sciatic, 122 sacro-spinosum, 122 sacro-tuberosum, 122 scapho-cuboid, 133 scapuloclavicular, 107 368 INDEX. Ligament or Ligaments, Schlemm's, 109 semilunar fibro-cartilages, 126 spheno-maxillary, 104 spino-glenoid, 105 stellate, 99 sterno-clavicular, 105 stylo-hyoid, 104 stylo-maxillary, 103 stylo-myloid, 103 subflava, 96, 179 subpubic, 121 suprascapular, 105 supraspinous, 96 suspensory of eye, 171 of penis, 145 talo-calcanea, 135 talo-cruralia, 135 talo-fibulare, 135 talo-naviculare, 136 talo-tibiale, 135 tarseum transversum, 137 tarso-metatarsea, 136 teres, 123 tibio-calcaneo-naviculare, 135 tibio-fibular, 131, 134 tibio-naviculare, 136 transverse, 98, 105, 114, 119, 123, 128, 132, 183 humeral, 109 of pelvis, 150 trapezoid, 107 triangular 147, 149 fibro-cartilage, 113 tuberculi costse, 101 tuberositatum vertebralium, 101 vaginalia, 119, 120, 179 vincula tendinum, 179 Ligula, 265 Lingual convolution, 257 Lingula, 263 mandibulse, 55 sphenoidal is, 44 Limbus sphenoidalis, 44 Line, buccal,-55 gluteal, 77 ilio-pectineal, 77 intertrochanteric, 81 oblique, 54, 71, 84, 85 popliteal, 84 spiral, 81 temporal, 37 Linea alba, 146 aspera, 81 Linea Douglasii, 147 quadrati, 81 semilunaris, 146 Spigelii, 148 splendens, 249 transversa, 146 Liver, 331 Lobe, central, 256 frontal, 255 occipital, 256 parietal, 255 temporo-sphenoidal, 256 Locus niger, 259 Lungs, 316 Lymphatic glands, axillary, 248 cervical, 248 inguinal, 245 mesenteric, 246 pelvic, 246 thoracic, 247 Lymphatics of lower limb, 245 of abdomen, 246 of head and neck, 248 of pelvis, 246 of thorax, 247 of upper limb, 247 M. Malleolus, 84 Mandible, 54 Marrow, 21 Meatus of nose, 48, 61 Mediastinum, 316 Medulla oblongata, 253 Membrana sacciformis, 113 tympani, 302 Meniscus, 126 Mesoblast, 17, 18 Midriff, 152 Modiolus, 305 Mouth, 318 Muscle or Muscles, abductor hallicis, 199 indicis, 185 minimi dig., 184, 200 ossis metatarsi quinti, 200 pollicis, 182, 184 accessorius, 179 acromio-clavicularis, 173 adductor brevis, 193 gracilis, 193 hallicis, 200 longus, 193 INDEX. 369 Muscle or Muscles, magnus, 193 minimus, 193 pollicis, 184 agitator caudse, 188 amygdalo-glossus, 163 anconeus, 176, 181 quintus, 176 epitrochlearis, 176 anomalus, 169 menti, 170 articularis genu, 191 aryteno-epiglottic, 313 arytenoideus, 314 atlanto-mastoideus, 145 auricularis, 166, 167 azygos pharyngis, 163 iivuke, 163 biceps, 174 femoris, 192 biveuter cervicis, 143 mandibulse, 158 brachialis anticus, 175 internus, 175 brachio-radialis, 180 buccinator, 169 bulbo-cavernosus, 152 caninus, 168 cephalo-pharyngeus, 162 cervico-costo-humeralis, 160 chondro-epitrochlearis, 154 chondroglossus, 161 ciliary, 299 circumflexus, 163 cleido-liyoideus, 159 cleido-occipital, 158 coccygeus, 151 complexus, 143 compressor hemispli. biilbi, 152 naris, 169 urethrse, 152 venae dorsalis penis, 152 constrictor of pharynx, 162 coraco-brachialis, 175 coraco-capsularis, 175 coraco minor, 175 corrugator supercilii, 167 costo-coracoid, 141 costo-fascialis, 160 cremaster, 148 crico-arytenoideus, 314 crico-hyoideus, 160 crico-thyroid, 313 crureus, 191 cubito-carpeus, 179 24— Anat. Muscle or Muscles, curvator coccygis, 151 deltoid, 173 depressor alee nasi, 169 anguli oris, 168 labii inferioris, 169 septi, 169 diaphragm, 152 digastric, 159 dilator naris, 169 dorso-epitrochlearis, 141, 176 ejaculator urinse, 152 epicranius, 166 temporalis, 166 erector penis, 151 spinas, 142 extensor brevis digit, 198 digit, manus, 182 pollicis, 182 carpi rad. access., 180 brevier, 180 coccygis, 143 intermedins, 180 longior, 180 ulnaris, 181 communis digit., 180 digiti quinti, 181 hallicis brevis, 199 indicis proprius, 182 longus hallicis, 195 digit., 195 primi internodii hall., 195 pollicis, 182 medii digiti, 182 minimi digiti, 181 ossis metac. poll., 182 primi interned, poll., 182 sec. intern, poll., 182 flexor brevis digit., 199 accessorius, 199 hall., 200 min. dig., 184, 200 poll., 184 carpi radialis, 177 brevis, 179 ulnaris, 17/ brevis, 179 longus digitorum, 197 access., 197 hall., 198 pollicis, 179 sublimis digit., 178 profundus digit., 178 frontalis, 166 370 INDEX. Muscle or Muscles, gastrocuemius, 196 gemelli, 189 genio-hyoglossus, 161 genio-hyoideus, 160 glosso-staphylinus, 163 glutei, 188 gluteo-perinealis, 151 gracilis, 171, 193 Horner's, 167 hyoglossus, 161 hyo-pharyngeus, 162 hyo-thyroideus, 160 iliacus, 187 minor, 188 ilio-costalis cervicis, 143 dorsi, 143 lumborum, 143 ilio-psoas, 187 incisivi, 169 indicator, 182 infraspinatus, 173 interclavicular, 154 intercostales, 156 interossei, 185, 200 interspinales, 144 intertransversales, 144 intertransversarii, 165 ischio-aponeuroticus, 193 ischio cavern osus, 151, 152 ischio-coccygeus, 151 labii proprius, 169 laryngo-pharyngeus, 162 latissimus dorsi, 140 anguli oris, 168 labii sup., 168 levator ani, 151 claviculse, 158 menti, 170 palati, 163 palpebral, 170 scapulae, 165 levatores costarum, 144 lingualis, 161 longissimus capitis, 143 cervicis, 143 dorsi, 143 longus atlantis, 165 capitis, 165 colli, 165 lumbricales, 183, 199 malaris, 167 masseter, 171 mental is, 170 Muscle or Muscles, mento-liyoid, 158 multifidus, 144 myloglossus, 161 mylohyoideus, 160 nasalis, 169 naso-labialis, 169 oblique, inferior, 170 superior, 170 obliquus capitis, 144 externus, 146 internus, 147 obturator, 189 occipitalis, 166 minor, 157 occipito-frontalis, 166 occipito-pharyngeus, 163 occipito-scapularis, 140 of abdomen, 145 of arm, 174 of back, 139 of breast, 154 of foot, 198 of forearm, 176 of hand, 183 of head, 166 of hip, 187 of hyoid bone, 158 of leg, 195 of neck, 157 of orbit, 170 of palate, 163 of perineum, 150 of pharynx, 162 of scapula, 173 of thigh, 190 of tongue, 161 of trunk, 139 omo-hyoideus, 159 opponens hallicis, 200 minimi dig., 185, 200 pollicis, 184 orbicularis oculi, 167 oris, 169 palato-glossus, 163 palato-pharyngeus, 163 palato-staphylinus, 163 palmaris brevis, 183 longus, 177 papillares, 206 pectinati, 205 pectineus, 193 pectoralis major, 154 minor, 155 minimus, 155 INDEX. 371 Muscle or Muscles, peroneo-calcaneus, 198 peroneo-tibialis, 197 peroneus access., 196 brevis, 196 longus, 195 quartus, 196 quint, digiti, 196 tertius, 195 petro-pharyngeus, 163 petro-staphylinus, 163 pharyngo-mastoideus, 163 pharyngo-staphylinus, 163 pisi-annularis, 185 pisi-metacarpeus, 185 pisi-uncinatus, 185 plantaris, 197 platysma myoides, 157 popliteus, 197 minor, 197 pronator quadratus, 179 teres, 177 psoas magnus, 188 parvus, 188 pterygoideus, 172 proprius, 172 pterygo-pharyngeus, 163 pterygo-spinosus, 172 pubo-coccygeus, 151 pubo-transversalis, 148 pyramidal is, 146 nasi, 169 pyriformis, 189 quadratus femoris, 189 labii sup., 168 lumborum, 187 menti, 169 plan tee, 199 quadriceps femoris, 190 radialis internus, 177 radio-carpeus, 179 recti of eye, 170 rectus abdominis, 145 capitis anticus, 165 lateralis, 145 posticus, 144 femoris, 191 lateralis abd., 146 rhombo-atloideus, 141 rhomboid eus major, 140 minor, 140 occipitalis, 140 risorius, 168 rotatores, 144 Muscle or Muscles, sacro-coccygeus, 143, 151 sacro-lumbalis, 142 sacro-spinalis, 142 sartorius, 190 scaleni, 164 scalenus minimus, 165 pleuralis, 165 semimembranosus, 192 semispinal es, 143 semitendinosus, 192 serratus anticus, 155 magnus, 155 posticus, 141 soleus, 196 spheno-pbaryngeus, 163 spheno-staphylinus, 163 sphincter ani, 151 oris, 169 spinales, 143 splenius, 141 capitis access., 141 colli access., 141 stapedius, 304 sternalis iDrutorum, 154 sterno-clavicularis, 154 sterno-cleido-mastoid, 158 sterno-hyoideus, 159 sterno-scapularis, 154 sterno-thyreoideus, 160 stylo-auricularis, 161 stylo-glossus, 161 stylo-hyoideus, 159 alter, 159 profundus, 159 stylo-pharyngeus, 162 subanconeus, 176 subclavius, 154 subcruralis, 191 subcutaneus colli, 157 subdeltoid, 173 subscapularis, 174 minor, 174 supinator brevis, 182 longus, 180 access., 180 supraclavicularis, 154 proprius, 158 supracostalis, 156 supraspinatus, 173 temporal, 172 minor, 172 tensor palati, 163 tarsi, 167 372 INDEX. Muscle or Muscles, tensor trochlese, 171 tympani, 304 vaginse femoris, 190 teres major, 140 minor, 173 thyreo-hyoideus, 160 tliyro-arytenoid, 313 thyro-epiglottic, 313 tibialis anticus, 194 posticus, 197 secundus, 197 tibio-fascialis, 195 trachelo-mastoid, 143 transversalis abd., 148 cervicis, 143, 165 transversi thoracis, 156 transverso-spinalis, 143 transversus colli, 160 menti, 168 nuchse, 158 orbitse, 171 pedis, 200 perinei, 151 profundus, 152 trapezius, 139 triangularis menti, 168 sterni, 156 triceps, 175 surse, 196 triticeo-glossus, 161 trochlearis, 170 ulnaris extern us, 181 internus, 177 brevis, 179 quinti digiti, 181 ulno-carpeus, 179 vasti, 191 zvgomaticus, 168 Myology, 19, 138 isr. Nasion, 63 Nerve or Nerves, abducens, 271 anterior crural, 286 Arnold's, 275 auditory, 273 auricularis magnus, 279 auriculo-temporal, 270 cardiac, 276, 293 chorda tympani, 272, 304 ciliary, 268 circumflex, 281 Nerve or Nerves, communicans noni, 279 cranial, 266 descendens noni, 277 dorsal, 283 facial, 272 genito-crural, 285 glosso-pharyngeal, 273 gluteal, 288 gustatory, 271 hypoglossal, 277 ilio-hypogastric, 285 ilio-inguinal, 285 inferior maxillary, 270 infraorbital, 269 interosseous, 282, 283 Jacobson's, 274, 304 laryngeal, 275 lingual, 271,274 lumbar, 283 median, 281 motor oculi, 267 musculo-cutaneous, 281, 291 musculo-spiral, 283 nasal, 268, 269 obturator, 286 occipitalis minor, 279 olfactory, 266 ophthalmic, 267 optic, 266 orbital, 269 pathetic, 267 perineal, 289 peroneal, 291 petrosal, 270, 272, 274 pharyngeal, 270, 275 phrenic, 279 plantar, 290 pneumogastric, 274 popliteal, 289, 291 pudic, 289 radial, 283 saphenous, 287 sciatic, 288, 289 spinal accessory, 276 splanchnic, 294 suboccipital, 277 superficialis colli, 279 superior maxillary, 269 suprascapular, 280 sympathetic, 292 thoracic, 280 tibial, 290, 291 trifacial, 267 INDEX. 373 Nerve or Nerves, tympanic, 272, 274 ulnar, 282 Vidian, 270 Neural arch, 24 Neuroglia, 251 Neurology, 19, 249 Nose, 307 Notch, coraco-scapular, 67 cotyloid, 79 episternal, 32 ethmoidal, 38 great scapular, 66 iliac, 77 ilio-sciatic, 78 intercondylar, 82 jugular, 37 lachrymal, 49 nasal 38, 48 parietal, 40 popliteal, 84 pterygoid, 48 sciatic, 77, 79, 122 semilunar, 32, 55 sigmoid, 55 spheno-palatine, 52 suprascapular, 67 vertebral, 24 Notochord, 17 Nucleus amygdalae, 260 caudate, 260 lenticular, 260 o. Obelion, 63 Obex, 265 Occipital point, 63 CEsophagus, 322 Olecranon, 70 Olfactory tract, 258 Olivary body, 253 Omentum, 341 Operculum, 256 Ophryon, 63 Opisthion, 64 Optic commissure, 258, 266 thalamus, 261 tract, 258, 266 Orbital plate, 38, 45, 47 Orbits, 57 Organ of Corti, 307 Os acetabuli, 79 capitatum, 74 central e, 75 Os coxa3, 76 innominatum, 76 planum, 47 pubis, 78 trigonum, 88 Ossa supersternalia, 32 fcriquetra, 56 Ossiculum jugulare, 56 Ossification, 20 Osteology, 19 Ovary, 351 Palate, 320 Palatine trigone, 49 Pancreas, 324 Panniculus adiposus, 139 carnosus, 139 Parietal boss, 37 Parovarium, 352 Pars intermedia, 272 Patella, 83 Peduncles of cerebellum, 263 Pelvic girdle, 91, 120 Pelvis, 76, 79 position of, 80 difierences in, 80 Penis, 342 Pericardium, 204 Perimysium, 138 Periosteum, 20 Peritoneum, 339 Pes accessorius, 259, 260 hippocampi, 260 Phalanges, 76, 89 Pharynx, 322 Pia mater, 249, 252 Pillar of fauces, 163 Pineal gland, 262 Pituitary body, 258 Pleura, 315 Plexus, brachial, 280 • cardiac, 294 carotid, 292 cavernous, 292 cervical, 278 epigastric, 295 lumbar, 284 pelvic, 296 sacral, 288 Pons Varolii, 254 Porus acusticus, 42 Posterior nares, 59 374 INDEX. Precuneus, 257 Primitive streak, 17, 18 Process, accessory, 27 alveolar, 49 angular, 38 articular, 24, 31 clinoid, 44, 45 cochleariform, 43 coracoid, 66 coronoid, 55, 70 ensiform, 32 ethmoidal, 54 frontal, 52 liamular, 46, 54 incisor, 50 intrajugular, 37 jugular, 36 lachrymal, 54 malar, 49 mammillary, 27 marginal, 53 mastoid, 40 maxillary, 51, 54 nasal, 38, 49 odontoid, 25 orbital, 51, 53 palate, 49 paramastoid, 37 petrosal, 44 pyramidal, 51 sphenoidal, 51 spinous, 24, 30, 45 styloid, 43, 71, 72, 75, 85 superior turbinate, 48 supracondylar, 69 transverse, 24, 30 tubarius, 46 uncinate, 47, 74 ungual, 76 vaginal, 43, 44, 46 xiphoid, 32 Processes of Ingrassias, 45 pterygoid, 44, 46 Pyramid, 253 R. Eadio-carpal joint, 115 Kadius, 71 Eeceptaculum chvli, 245 Eectum, 329 EeStiform body, 253 Eetina, 299 Eibs, vertebro-sternal, 32 Eibs, vertebro-chondral, 32 vertebral, 32 Eidge, gluteal, 81 mylo-hyoid, 55 pectoral, 68 pronator, 71 superciliary, 38 supinator, 68, 70 supracondylar, 68, 81 Eing, abdominal, 146, 149 crural, 187 femoral, 149 Eostrum, 45, 259 S. Saccus endolymphaticus, 42 Sacrum, 28 Sagittal plane, 19 Saphenous opening, 187 Sarcolemma, 138 Scapula, 65 Scarpa's triangle, 229 Sclerotic coat, 298 Scrotum, 345 Segmentation sphere, 17 Sella turcica, 44 Semilunar valves, 206 Septum crurale, 187 lucidum, 259, 261 nasi, 60 tubse, 43 Sesamoid plate, 138 Sheath, crural, 187 of rectus, 147 Shoulder, 64 Shoulder-girdle, 90, 104 Shoulder-joint, 107 Sigmoid cavity, 70, 72 Sinus, cavernous, 238, 271 circular, 238 coronary, 233 frontal, 38 lateral, 238 longitudinal, 238 magnus, 209 maxillary, 50 occipital, 238 petrosal, 238 straight, 238 transverse, 239 Skeleton, 19 Skull, as a whole, 55 fixed points on, 63 INDEX. 375 Somatopleure, 18 Spermatic cord, 344 Spheno-ethmoidal recess, 61 Spheno-petrosal lamina, 47 Spinal cord, 249 Spine, 44 iliac, 79 nasal, 48, 51 of ischium, 77 of pubis, 77 of scapula, 66 of tibia, 84 palatine, 51 peroneal, 8^ Spines, mental, 54 Splanchnology, 19, 310 Splanchnopleure, 18 Spleen, 335 Splenium, 259 Stapes, 303 Stephanion, 64 Sternum, 31 Stomach, 323 Striae acousticse, 265 Subnasal point, 63 Substantia ferruginea, 266 gelatinosa, 251 Sulci of brain, 255 Sulcus, frontal, 39 ^occipitalis, 41 preauricular, 79 pulmonalis, 34 Superior maxilla, 48 Supination, 112, 131 Suprarenal capsule, 335 Sustentaculum tali, 86 Sutures, coronal, 56 lambdoid, 56 sagittal, 56 Symphysis pubis, 78, 120 Synarthrodia! joints, 93 Synchondrosis, 94 Syndesmosis, 94 Synovial cavities of ankle, 137 of wrist, 116 membrane, 93 T. Taenia semicircularis-, 260 Talus, 86 Tarsus, 86 Teeth, 318 Tegmen tympani, 40, 42 Tegmentum, 259 Tendo Achillis, 197 oculi, 167 Tentorium, 252 Testis, 344 Thigh, 80 Thorax, 31, 34 Tibia, 83 Tongue, 309 Tonsil, 263, 320 Torcular Herophili, 36 Torus occipitalis transversus, 37 Trachea, 314 Tractus spiralis foraminulentus, 42 Tragus, 301 Trapezium, 254 Triangle of Petit, 147 suboccipital, 145 Trochanters, 81 Trochlea, 69 Tuber annulare, 254 ] cinereum, 258 olfactorium, 258 Tubercle, adductor, 82 carotid, 26 Chassaignac's, 26 conoid, 65 deltoid, 65 infraglenoid, 67 lachrymal, 49 Lisfranc's 33 mental, 54 obturator, 78 of femur, 81 of radius, 72 of the quadratus, 81 of tibia, 84 pharyngeal, 37 pterygoid, 46 scalene, 33 supraglenoid, 67 Tubercles of astragalus, 87 Tuberosity, bicipital, 71 costal, 65 great, 68 iliac, 77 of ischium, 78, 79 of scaphoid, 73, 87 small, 68 of superior maxilla, 48 of the palate-bone, 51 of tibia, 83 of trapezium, 74 of ulna, 70 376 INDEX. Tuberosity, pubo-ischiatic, 78 Tympanic plate, 44 Tympanum, 301 u. Ulna, 70 Ureter, 337 Urethra, 343, 349 Uterus, 349 Vagina, 349 Valve of Vieusseus, 263, 265 Vas deferens, 347 Vein or Veins, angular, 235 axillary, 240 azygos, 240, 241 basilic, 240 cardiac, 233 cava inferior, 241 superior, 233 cephalic, 240 cerebellar, 237 cerebral, 237 cervical, 234 coronary, 233 corporis striati, 237 diploic, 239 emissary, 239 facial, 235 femoral, 243 hepatic. 242 iliac, 242, 243 innominate, 234 intercostal, 235 internal maxillary, 236 jugular, 236, 237 lumbar, 241 magna Galeni, 237 median, 240 oblique of Marshall, 233 ophthalmic, 239 Vein or Veins, popliteal, 243 portse, 244 pudic, 243 . pulmonary, 233 renal, 242 saphenous, 242 spermatic, 242 spinal, 241 subclavian, 240 systemic, 233 temporal, 236 temporo-maxillary, 235 thyroid, 234 tibial, 243 ulnar, 240 vertebral, 234 Velum interpositum, 261 medullary, 263, 265 palati, 163 Ventricles, 205 of brain, 259, 262, 263 Vertebra dentata, 25 prominens, 25 Vertebrse, cervical, 24 characteristics of, 23 dorsal, 26 false, 28 lumbar, 26, 27 sacral, 28 Vertebral, 25 column, 23, 29 Vestibule, 305 Vincula tendinum, 179 Vitelline membrane, 17 Vocal cords, 312 Vulva, 348 w. "White line," 150 Wings of sphenoid, 44, 45 Wrist-bones, 72 Wrist-joint, 113 Jj^ea ^J'othcrs Sc Go's LIST OF THE Leading Medical Text-Books. GRAYS ANATOMY. 13th Edition. In Colors or Black. ANATOMY, DESCRIPTIVE AND SURGICAL. BY HENRY GRAY, F.R.S., LECTURER ON ANATOMY AT ST. GEORGe's HOSPITAL, LONDON. EDITED BY T. PICKERING PICK, F.R.C.S., SURGEON TO AND LECTURER ON ANATOMY AT ST. GEORGE's HOSPITAL, LONDON. A NEW AMERICAN FROM THE THIRTEENTH ENLARGED AND IMPROVED LONDON EDITION, THOROUGHLY REVISED. In one imperial octavo volume of iioo pages, with 635 large and elaborate engravings on wood. Price of edition in black : cloth, $6.00 ; leather, $7.00. Price of edition in colors: cloth, $7.00; leather, $8.00. Just ready. A New Medical Dictionary— Ready Shortly. A DICTIONARY OF MEDICINE AND THE ALLIED Sciences. Comprising the Pronunciation, Derivation and Full Expla- nation of Medical Terms ; together with Much Collateral Descriptive Matter, Numerous Tables, etc. By Alexander Duane, M. D., Assistant Surgeon N. Y. Ophthalmic and Clinical Institute; Reviser of Medical Terms for Webster's International Dictionary. In one very handsome square octavo volume of about GOO pages. Heady very ahurUy. LEA BROTHERS & CO., 706, 708 & 710 Sansom Street, Philadelphia, NEW (TWENTY-FIRST) EDITION. JUST READY. DUNQLISON'S MEDICAL DICTIONARY. A DICTIONARY OF MEDICAL SCIENCE CONTAINING A FULL EXPLANATION OF THE VARIOUS SUBJECTS AND TERMS OF ANATOMY, PHYSIOLOGY, MEDICAL CHEMISTRY, PHARMACY, PHARMACOLOGY, THERAPEUTICS, MEDICINE, HYGIENE, DIETETICS, PATHOLOGY, BACTERIOLOGY, SURGERY, OPHTHALMOLOGY, OTOLOGY, LARYNGOLOGY, DERMATOLOGY, GYNECOLOGY, OBSTETRICS, PEDIATRICS, MEDICAL JURIS- PRUDENCE, DENTISTRY, ETC. By ROBLEY DUNQLISON, fl. D., LL. D. New (aist) Edition, thoroughly Revised and greatly Enlarged and Improved. WITH THE PRONUNCIATION, ACCENTUATION AND DERIVATION OF THE TERMS. By RICHARD J. DUNQLISON, A. fl., T\. D. In one magnificent imperial octavo volume of 1200 pages. Cloth, $7 ; leather, $8. Just ready. TWENTY-ONE editions in sixty years corroborate the recognized position of Dunglison's Dictionary as being the standard in all matters of medical terminology. Forty-four thousand new words and phrases have been added in the new edition, and notwithstanding the omission of everything obsolete, the work has been enlarged by an amount of matter equal to one hundred pages of the previous edition ; pronunciation has been introduced for the first time and is indicated by a simple phonetic spelling ; derivation, an unequalled aid to memory, is fully given, and the definitions, for which *' Dunglison " has always been distinguished, are full, clear and explanatory. The work abounds in information of practical importance, such as Diseases, isymptoms and treatment ; Poisoning, treatment, antidotes ; Drugs, properties and doses, of which latter a full table is given; etc. Numerous tables enrich the alphabet and place an immense amount of knowledge clearly and conveniently at hand. In its present improved shape this standard work will be found indispensable to students, practitioners and pharmacists. LEA BROTHERS & CO., 706, 70$ & 710 Sansom Street Philadelphia, Anatomy ^ Oictionaries. Billings' National Medical Dictionary. THE NATIONAL MEDICAL DICTIONARY; including English, French, German, Italian and Latin technical terms used in Medi- cine and the Collateral Sciences, and a series of tables of useful data. By John S. Billings, M. D., LL. D., Edin. and Harv., D. C. L., Oxon., Member of the National Academy of Sciences, Surgeon U. S. A., etc. In two very handsome royal octavo volumes containing 1574 pages, with two colored plates. Per volume, cloth, $6.00; leather, |7.00; half Morocco, marbled edges, $8.50. For sale by subscription only. Specimen pages on application. Address the publishers. Its scope is one which will at once satisfy the student and meet all the requirements of the medical practitioner. It presents to the English reader a thoroughly scientific mode of acquiring a rich vocabulary and offers an accurate and' ready means of refer- ence in consulting works in any of the three modern continental languages which are richest in medical literature. There cannot be two opinions as to the great value and usefulness of this dictionary as a book of ready reference for all sorts and conditions of medical men. So far as we have been ab'e to see, no subject has been omitted, and in respect of completeness it will be found distinctly superior to any medical lexicon yet published. — The London Lancet^ Aprils, 1890. Hoblyn's Medical Dictionary. A DICTIONARY OF THE TERMS USED IN MEDICINE and the Collateral Sciences. By Kichaed D. Hoblyn, M. D. Eevised, with numerous additions, by Isaac Hays, M. D., late editor of The Amer- ican Journal of the Medical Sciences. In one large royal 12mo. volume of 520 double-columned pages. Cloth, $1.50 ; leather, $2.00. It is the best book of definitions we have, and ought always be upon the student's table. — Sout/iern Medical and Surgical Journal. Holden's Landmarks, Medical and Surgical. LANDMARKS, MEDICAL AND SURGICAL. By Luther Holder, F. E. C. S., Surgeon to St. Bartholomew's and the Foundling Hospitals, London. Second American from the third and revised English edition, with additions by W. W. Keen, M. D., Professor of Artistic Anatomy in the Pennsylvania Academy of Fine Arts. In one 12mo. volume of 148 pages. Cloth, $1.00. Ellis' Demonstrations of Anatomy— Eighth Edition. DEMONSTRATIONS OF ANATOMY. Being a Guide to the Knowledge of the Human Body by Dissection. By Geokge Viner Ellis, Emeritus Professor of Anatomy in University College, London. From the eighth and revised London edition. In one very handsome octavo volume of 716 pages, with 249 illustrations. Cloth, $4.25; leather, $5.25. LEA BROTHERS & CO., 706, 708 & 710 Sansom Street, Philadelphia. Phx^sics ^ Phx^siologx?* Draper's Medical Physics. MEDICAL PHYSICS. A Text-book for Students and Practi- tioners of Medicine. By John C. Draper, M. D., LL. D., Professor of Chemistry in the University of the City of New York. In one octavo vol- ume of 734 pages, with 376 woodcuts. Cloth, $4.00. agree that a knowledge of physics is desi- rable for the medical student, only those actually engaged in the teaching of the pri- mary subjects can be fully aware of the diffi- culties encountered by students who attempt the study of these subjects without a knowl- edge of either physics or chemistry. These are especially felt by the teacher of physi- ology. It is, however, impossible for him to impart a knowledge of the main facts of his subject and establish them by reasons and experimental demonstrations, and at the same time undertake to teach ab initio the principles of chemistry or physics. Hence the desirability, we may say the necessity, for some such work as the present one. — The Montreal Medical Journal, July, 1890. No man in America was better fitted than Dr. Draper for the task he undertook, atd he has provided the student and practitioner of medicine with a volume at once readable and thorough. Even to the student who has some knowledge of physics this book is use- ful, as it shows him its applications to the profession that he has chosen. Dr. Draper, as an old teacher, knew well the difficulties to be encountered in bringing his subject within the grasp of the average student, and that he has succeeded so well proves once more that the man to write for and examine students is the one who has taught and is teaching them. The book is well printed and fully illustrated, and in every way de- serves grateful recognition. While all enlightened physicians will Power's Physiology. HUMAN PHYSIOLOGY. By Henry Power, M.B., F.R.C.S., Examiner in Physiology, Royal College of Surgeons of England. Second edition. In one 12mo. volume of 509 pages, with 68 illustrations. Cloth, 11.50. See Students^ Series of Manuals^ at end. Robertson's Physiological Physics. PHYSIOLOGICAL PHYSICS. By J. McGregor Robertson, M. A., M. B., Muirhead Demonstrator of Physiology, University of Glas- gow. In one 12mo. volume of 537 pages, with 219 illustrations. Limp cloth, $2.00. See Students'' Series of Ilanuals, at end. Bell's Comparative Anatomy and Physiology. COMPARATIVE ANATOMY AND PHYSIOLOGY. By F. Jeffrey Bell, M. A., Professor of Comparative Anatomy at King's College, London. In one 12mo. volume of 561 pages, with 229 illustrations. Limp cloth, |2.00. See Students^ Series of 3Ianu(ds, at end. LEA BROTHERS & CO., 70S, 708 & 7t0 Sansom Street, Philadelphia, ^ Ph\?siolog \? — (Continu ed). v Foster's Physiology— New American Edition. TEXT BOOK OF PHYSIOLOGY. By Michael Foster, M.D., F R S., Prelector in Physiology and Fellow of Trinity College, Cambridge, England. New (fourth) and enlarged American from the fifth and revised English edition, with notes and additions. In one handsome octavo volume of 1072 pages, with 282 illustrations. Cloth, $4.50; leather, |5.50. The appearance of another edition of Foster'r Physiology again reminds us of the continued popularity of this most excellent work There can be no doubt that this text- book not only continues to lead all others in the English language, but that this last edi- tion is superior to its predecessors. Every page bears evidences of careful revision. Although the work of the American editor in former editions has been by the author largely adopted in a modified form in this revision, much was still left to be done by the editor to render the work fully adapted to the wants of our American students, so that the American edition will undoubtedly continue to supply the market on this side of the Atlantic. The work has been pub- lished in the characteristic creditable style of the Leas, and owing to its enormous sale is offered at an extremely low price. — The Medical and Surgical Reporter ^ January 9,'52. Foster's Physiology would probably be placed by universal verdict at the head of all works of its class that the English-speak- ing world has yet produced. It appears to be a complete storehouse of physiological lore. The work is deserving of unstinted praise. — American Practitioner and I^ews, March 12, 1892. Dallon's Pliysiology— Seventh Edition. A TREATISE ON HUMAN PHYSIOLOGY. Designed for the Use of Students and Practitioners of Medicine. By John C. Dalton, M.D., Professor of Physiology in the College of Physicians and Surgeons, New York. Seventh edition, thoroughly revised. In one octavo volume of 722 pages, with 252 engravings. Cloth, |5.00; leather, |6.00. From the first appearance of the book it has been a favorite, owing as well to the author's renown as an oral teacher as to the charm of simplicity with which, as a writer^ he always succeeds in investing even intri- cate subjects. It must be gratifying to him to observe the frequency with which his work, written for students and practitioners, is quoted by other writers on physiology. This fact attests its value, and, in great measure, its originality. It now needs no such seal of approbation, however, for the thousands who have studied it in its various editions have never been in any doubt as to its sterling worth. — New York Medical JouT' naU October, 1882. Chapman's Physiology. A TREATISE ON HUMAN PHYSIOLOGY. By Henry C. Chapman, M. D., Professor of Institutes of Medicine and Medical Juris- prudence in Jefferson Medical College of Philadelphia. In one octavo vol- ume of 925 pages, with 605 engravings. Cloth, |5.50; leather, $6.50. Matters which have a practical bearing on the practice of medicine are lucidly ex- pressed ; technical matters are given in min- iitedetail; elaborate directions are stated for the guidance of students in the laboratory. In every respect the work fulfils its promise, whether as a complete treatise for the stu- dent or for the physician; for the former it is so complete that he need look no farther. —North Carolina Medical Journal^ Nov. 1887, The Students' Quiz Series— fhysioloot, $i. see f. LEA BROTHERS & CO., 706, 708 & 710 Sansom Street, Philadelphia. CheinistrxJ. Bloxam's Chemistry— Fifth Edition. CHEMISTRY, INORGANIC AND ORGANIC. By Charles L. Bloxaini, Professor of Chemistry in King's College, London. New American from the fifth London edition, thoroughly revised and much im- proved. In one very handsome octavo volume of 727 pages, with 292 illus- trations. Cloth, $2.00; leather, $3.00. We know of no treatise on chemistry which contains so much practical informa- tion in the same number of pages. The book can be readily adapted not only to the needs of those who desire a tolerably com- plete course of chemistry, but also to the needs of those who desire only a general knowledge of the subject. It is both a satis- factory text-book, and a useful book of refer- ence. — Boston Medical and Surgical Journal^ June 19, 1884. Frankland & Japp's Inorganic Chemistry. INORGANIC CHEMISTRY. By E. Frankland, D. C. L., F. R. S., Professor of Chemistry in the Normal School of Science, London, and F. R. Japp, F. I. C, Assistant Professor of Chemistry in the Normal School of Science, London. In one handsome octavo volume of 677 pages with 51 woodcuts and 2 plates. Cloth, |3.75; leather, |4.75. This work should supersede other works of its class in the medical colleges. It is cer- tainly better adapted than any work upon chemistry, with which we are acquainted, to impart that clear and full knowledge of the science which students of medicine should have. Physicians who feel that their chem- ical knowledge is behind the times, would do well to study this work. The descriptions aud demonstrations are made so plain that there is no difficulty in understanding them. — Cincinnati Medical News, January, 1886, Luff's Manual of Chemistry— Just Ready. A MANUAL OF CHEMISTRY. For the Use of Students of Medicine. By Arthur P. Luff, M. D., B. Sc, Lecturer on Medical Juris- prudence and Toxicological Chemistry, St. Mary^s Hospital Medical School, London. In one 12mo. volume of 522 pages, with 36 engravings. Cloth, 12.00. See Students^ Series of Manuals^ at end. Greene's Medical Chemistry. A MANUAL OF MEDICAL CHEMISTRY. For the Use of Students. Based upon Bowman's Medical Chemistry. By William H. Gbeene, M. D., Demonstrator of Chemistry in the Medical Department of the University of Pennsylvania. In one 12mo. volume of 310 pages, with 74 illustrations. Cloth, |1.75. LEA BROTHERS & CO, 706, 708 & 710 Sansom Street, Philadelphia. Chemistr\? — (Continued). Simon's Manual of Chemistry— New (4th) Edition. MANUAL OF CHEMISTRY. A Guide to Lectures and Lab- oratory Work for Beginners in Chemistry. A Text-book, specially adapted for Students of Pharmacy and Medicine. By W. Simon, Ph. D., M. D., Prof, of Chemistry in the College of Physicians and Surgeons, Baltimore, Professor of Chem. in the Md. College of Pharm. New (fourth) edition. In one 8vo. volume of about 500 pages, with 44 woodcuts and 7 colored plates illustrating 56 of the most important chemical tests. Cloth, |3. 25. Just Ready. A notice of the previous edition is appended. While possessing all the usual qualities of an excellent text-book for the student or laboratory, this Manual presents the unique advantage of furnishing plates show- ing the variously shaded colors of certain ehomicals, etc., and their reactions. This Chemistry is especially valuable to medi- cal students and practitioners, as devoting so much of detail to descriptions of analyses, tests, etc., of those things with which the doctor has mostly to deal. — Virginia Medical Monthly^ January, 1892. Attfield's Chemistry— Twelfth Edition. CHEMISTRY, GENERAL, MEDICAL AND PHARMA- ceutical ; Including the Chemistry of the U. S. Pharmacopoeia. A Manual of the General Principles of the Science, and their Application to Medicine and Pharmacy. By Johit Attfield, M. A., Ph.D., Prof of Practical Chemistry to the Pharm. Soc. of Great Britain. A new American, from the 12th English edition, specially revised by the author for America. In one 12mo. volume of 782 pages, with 88 illus. Cloth, $2.75; leather, $3.25. out. His book is precisely what the title claims for it. The admirable arrangement of the text enables a reader to get a good idea of chemistry without the aid of experi- ments, and again it is a good laboratory guid6 and finally it contains such a mass of well- arranged information that it will always serve as a handy book of reference. This last edi tion shows the marks of the latest progress made in chemistry and chemical teaching. — New Orleans Med. & Surg. Jour.j Nov. 1889. Attfield's Chemistry is the most popular book among students of medicine and pharmacy. This popularity has a good, substantial basis. It rests upon real merits. Attfield's work combines in the happiest manner a clear exposition of the theory of chemistry with the practical application of this knowledge to the everyday dealings of the physician and pharmacist. His discern- ment is shown not only in what he puts into his work, but also in what he leaves Fownes' Chemistry— Twelfth Edition. A MANUAL OF ELEMENTARY CHEMISTRY; Theo- retical and Practical. By George Fownes, Ph. D. Embodying Watts^ Physical and Inorganic Chemistry. New American, from the twelfth English edition. In one large royal 12mo. volume of 1061 pages, with 168 illustra- tions on wood and a colored plate. Cloth, $2.75; leather, $3.25. Of all the works on chemistry intended for the use of medical students, Fownes' Chem- istry is perhaps the most widely used. Its popularity is based upon its' excellence. This last edition contains all of the material found in the previous, and it is also enriched by the addition of Watts' Physical and In- organic Chemistry. All of the matter is brought to the present standpoint of chem- ical knowledge. We may safely predict for this work a continuance of the fame and favor it enjoys among medical students. — New Orleans Medical and Surgical Journal ^ March, 1886. The Students' Quiz Series— Chemistry, $1. See P. 1. LEA BROTHERS & CO.. 706, 708 <£ 710 Sansom Street. Philadelphia. Chemistrxp— (Continued). Remsen's Theoretical Chemistry— new (4th) edition. PRINCIPLES OF THEORETICAL CHEMISTRY, with special reference to the Constitution of Chemical Compounds. By Ira Eemsen, M. D., Ph. D., Professor of Chemistry in the Johns Hopkins Uni- versity, Baltimore. Fourth and thoroughly revised edition. In one hand- some royal 12mo. volume of 325 pages. Cloth, $2.00. Just ready. No comment need be made on the excel- lence of this work. As a guide to the study of 'J'heoietiealGheniistry it remains unequalled, The favor which has been shown preceding editions of the work is sufficient proof that the object of the author in enabling students to obtain clear ideas in regard to the funda- mental principles of chemistry has been suc- cessfully accomplished. Since the publica- tion of the last edition in 1887, the work has been translated into German and into Italian —certainly no greater compliment could be desired by any author. The work will con- tinue deservedly to hold the fi rst place among the numerous treatises on Theoretical Chem- istry.— Pac//ic Medical Journal, Oct. 1892. Vaughan & Novy on Ptomaines and Leucomaines. New (2d) Edition. PTOMAINES, LEUCOMAINES AND BACTERIAL PRO- teids ; or the Chemical Factors in the Causation of Disease. By Victor C. Vaughan, Ph.D., M.D., Professor of Physiological and Pathologi- cal Chemistry and Associate Professor of Therapeutics and Materia Medica in the University of Michigan, and Frederick G. Novy, M. D. , Instructor in Hygiene and Physiological Chemistry in the University of Michigan. New (second) edition. In one handsome 12mo. volume of 398 pp. Cloth, |2.25. The fact that a second edition appears within three years of the first is suflScient proof that it has been received by the profes- sion with more than common interest. This may largely be accounted for by the system atic arrangement and the practical manner which the authors successfully adopted for it. This book is one of the greatest importance, and the modern physician who accepts bac- terial pathology cannot have a complete knowledge of this subject unless he has care- fully perused it. To the toxicologist the sub- ject is alike of great import, as well as to the hygienist and sanitarian. It contains in- formation which is not easily obtained else- where, and which is of a kind that no medi- cal thinker should be without.— T-^c ^men- can Jour, of the Med. Sciences^ April, 1892. Clowes' Chemical Analysis— Third Edition. AN ELEMENTARY TREATISE ON PRACTICAL CHEM- istry and Qualitative Inorganic Analysis. Specially adapted for use in Laboratories of Schools aud Colleges and by Beginners. By Fkank Cix)WES, D. Sc, London, Senior Science-Master at the High School, Newcastle-under- Lyme, etc. Third American from the fourth and revised English edition. In one 12mo. volume of 387 pages, with 55 illustratious. Cloth, $2.50. Ralfe's Clinical Chemistry. CLINICAL CHEMISTRY. By Charles H. Ealfe, M.D., F. R. C. P., Assistant Physician at the London Hospital. In one pocket-size '12mo. volume of 314 pages, with 16 illustrations. Limp cloth, red edges, $1.50. See Students^ Series of Manuals, at end. LEA BROTHERS & CO., 706, 708 & 710 Sansom Street, Philadelphia ChemistrxJ # PharmacvJ #_jrherapeutics. Charles' Physiological and Pathological Chemistry. THE ELEMENTS OF PHYSIOLOGICAL AND PATHO- logical Chemistry. A Handbook for Medical Students and Practitioners. Containing a general Account of Nutrition, Foods and Digestion, and the Chemistry of the Tissues, Organs, Secretions and Excretions of the Body in Health and in Disease. Together with the methods for preparing or sepa- rating their chief constituents, as also for their examination in detail, and an outline syllabus of a practical course of instruction for students. By T. Cranstoun Charles, M. D., F. C. S., M. S., formerly Assistant Professor and Demonstrator of Chemistry and Chemical Physics, Queen's College, Belfast. Octavo, 463 pp. , 38 woodcuts and 1 colored plate. Cloth, $3.50. Parrish's Pharmacy— Fifth Edition. A TREATISE ON PHARMACY : Designed as a Text-book for the Student, and as a Guide for the Physician and Pharmacist. With many Formulae and Prescriptions. By Edward Parrish, Late Professor of the Theory and Practice of Pharmacy in the Philadelphia College of Pharmacy. Fifth edition, thoroughly revised, by Thomas S. Wiegand, Ph. G. Octavo volume of 1093 pages, with 256 illus. Cloth, |5.00; leather, $6.00. There is nothing to equal Parrish's Phar- macy in this or any other language.—- Zowdow Pharmaceutical Journal. This treatise on Pharmacy is as indispen- sable to the dispensing or manufacturing druggist and student of pharmacy as Dun- glison's Medical Dictionary is to the doctor and the student of medicine. It has ceased being a luxury, and has become a necessity. The work is not merely a text-book for phar- macy students and druggists, but is a valua- ble guide and compend for the physician and medical student. — The Physician and Surgeon, April, 1884. Griffith's Universal Formulary. A UNIVERSAL FORMULARY, containing the Methods of Preparing and Administering Officinal and other Medicines. The whole adapted to Physicians and Pharmaceutists. By Kobekt Eglesfield Griffith, M. D. Third edition, thoroughly revised, with numerous addi- tions, by John M. Maisch, Phar. D., Professor of Materia Medica and Botany in the Philadelphia College of Pharmacy. In one octavo volume of 775 pages, with 38 illustrations. Cloth, $4.50; leather, |5.50. £ruce's Materia Medica and Therapeutics— 5th Ed. MATERIA MEDICA AND THERAPEUTICS. An Intro- duction to Kational Treatment. By J. Mitchell Bruce, M. D. , F. R. C. P., Physician and Lecturer on Materia Medica and Therapeutics at Charing Cross Hospital, London. Fourth edition, 12mo., 591 pages. Cloth, |1.50. See Students' Series of Manuals^ at end. The pharmacology and tberapeutics of each drug are given with great fullness, and the indications for rational employment in the practical treatment of diseaf e are pointed out. — Medical Chronicle, May, 1891. LEA BROTHERS & CO , 706, 708 & 710 Sansom Street, Philadelphia, Thera pe utics # /Vlateria / Vledic a, Hare's Practical Therapeutics— ^^^ ^^^^ ™ust ready. A TEXT-BOOK OF PRACTICAL THERAPEUTICS ; With Especial Keference to the Application of Kemedial Measures to Disease and their Employment upon a Kationul Basis. By Hobart Amoky Haee, B. Sc, M. D., Professor of Materia Medicaand Therapeutics in the Jefierson Medical College of Philadelphia. With special chapters by Drs. G. E. de ScHWEiNiTZ, Edward Martin, J. Howard Keeves and Barton C. Hirst. New (third) and revised edition. In one handsome octavo volume of 689 pages. Cloth, $3.75; leather, $4.75. We find here directions for the use of the drugs of the most recent introduction, and the very latest results obtained in the treat- ment of disease by these newer remedies. There is also a list of drugs arranged accord- ing to their physiological action, and a list of definitions of the terms used to designate classes of drugs. In a word, this book is a treatise on drugs and other remedial meas- ures, with especial reference to their practi- cal uses ; and also a treatise on diseases, with full directions for the most approved treat- ment. The book closes with a table of doses and an index of diseases and remedies. There are some books that the student and practitioner alike would do well to purchase ; there are others they must have. To this latter class belong the text-books on practical therapeutics. Certainly none can be found either more practical or more complete than this.— 7%e hatmial Medical Jieview, Febru- ary 2, 1893. Hare's System of Practical Therapeutics— 3 Vols. A SYSTEM OF PRACTICAL THERAPEUTICS. By Ameri- can and Foreign Authors. Edited by Hobaet Amoey Haee, M. D.^ Professor of Therapeutics and Materia Medica in the Jefferson Medical Col- lege of Philadelphia. In a series of contributions by seventy-eight emi- nent authorities. In three large octavo volumes containing 3544 pages, with 434 illustrations. Price, per volume: Cloth, $5.00; leather, |6.00; half Russia, $7.00. For sale by subscription only. Address the Fublishers. Full prospectus free to any address on application. Stille & Maisch's National Dispensatory— 5th Edition. THE NATIONAL DISPENSATORY. Containing the Natural History, Chemistry, Pharmacy, Actions and Uses of Medicines. By Alfeed Stille, M. D., LL. D., Professor Emeritus of the Theory and Practice of Medicine and of Clinical Medicine in the University of Pennsylvania., and John M. Maisch, Phar. D., Professor of Materia Medica and Botany in the Philadelphia College of Pharmacy. New (5th) and revised edition. In one magnificent imperial octavo vol. of about 1750 pp., with about 315 elab- orate engravings. In Frees, A notice of the previous edition is appended, i since its first appearance in 1879. The en- The most comprehensive, elaborate and accurate work of the kind ever printed in this country. It is no wonder that it has become the standard authority for both the medical and pharmaceutical professions, and that four editions have been required to- supply the constant and increasing demand tire field has been gone over and the various articles revised in accordance with the latest developments regarding the attributes and therapeutical action of drugs. — Kansas City Medical Index, The Students' Quiz Series-M^'^- «|?: *slS ^m^^'^^^^- LEA BROTHERS & CO., 706, 708 & 710 Sansom Street, Philadelphia. Ther apeutics # Mate ria ^edica — (Cont^d), Brunton's Therapeutics and Mat. Med.— 3d Edition. A TEXT-BOOK OF PHARMACOLOGY, THERAPEUTICS and Materia Medica ; Including the Pharmacy, the Physiological Action and the Therapeutical Uses of Drugs. By T. Lauder Brunton, M. D., D. Sc, F. R. S., F. R. C. P., Lecturer on Materia Medica and Therapeutics at St. Bartholomew's Hospital, London, etc. Adapted to the U. S. Pharmaco- poeia by Francis H. Williams, M. D., of Harvard Univ. Med. School. Third edition. Octavo, 1305 pages, 230 illus. Cloth, |5.50; leather, |6.50. No words of praise are needed for this work, for it has already spoken for itself in former editions. It was by unanimous consent placed among the foremost books on the sub- ject ever published in any language, and the better it is known and studied the more highly it is appreciated. The present edition contains much new matter, the insertion of which has been necessitated by the advances made in various directions in the art of therapeutics, and it now stands unrivalled in its thoroughly scientific presentation of the modes of drug action. No one who wishes to be fully up to the times in this science can aflTord to neglect the study of Dr. Brunton's work. The indexes are excellent, and add not a little to the practical value of the hooli.— Medical Record, May 25, 1889 Farquharson's Therapeutics— Fourth Edition. A GUIDE TO THERAPEUTICS AND MATERIA Medica. By Robekt Farquhakson, M. D., F. R. C. P., LL. D., Lecturer on Materia Medica at St. Mary's Hospital Medical School, London. Fourth American, from the fourth English edition. Enlarged and adapted to the U. S. Pharmacopoeia. By Frank Woodbury, M. D., Professor of Materia Medica and Therapeutics and Clinical Medicine in the Medico-Chirurgical College of Philadelphia. In one 12mo. Yolume of 581 pages. Cloth, $2.50. and therapeutical actions of various remedies are shown in parallel columns. This aids greatly in fixing attention and facilitates study. The American editor has enlarged the work so as to include all the remedies and preparations in the United States Phar- macopoeia. Altogether the book is a most valuable addition to the list of treatises on this most important subject. — ITie American Practitioner and News, November 9, 1889. Farquharson's Therapeutics and 3fateria Medica has struck a happy medium between excessive brevity on the one hand and tedious prolixity on the other. Itdeals with the entire list of drugs embraced in the British PharmacopoBia in such a way as to give in a satisfactory form the established indications of each, excluding all irrelevant matter. An especially attractive feature is an arrangement by which the physiological Edes' Therapeutics and Materia Medica. A TEXT-BOOK OF THERAPEUTICS AND MATERIA Medica. Intended for the Use of Students and Practitioners. By Robert T. Edes, M. D., Jackson Professor of Clinical Medicine in Harvard Uni- versity, Medical Department. Octavo, 544 pages. Cloth, |3. 50; leather, |4. 50. The present work seems destined to take a prominent place as a text-book on the sub- jects of which it treats. It possesses all the essentials which we expect in a book of its kind, such as conciseness, clearness, a judi- cious classification, and a reasonable degree of dogmatism. The student and young practitioner need a safe guide in this branch of medicine, such they can find in the pre- sent author. All the newest drugs of prom- ise are treated of. The clinical index at the end will be found very useful. We heartily commend the book and congratulate the author on having produced so good a one. — N. Y. Medical Journal, February 18, 1888. Dr. Edes' book represents better than any older book -the practical therapeutics of the present day. The book is a thoroughly prac- tical one. The classification of remedies has reference to their therapeutic action. — Phar' maceutical Era^ January, 1888. LEA BROTHERS & CO., 706, 708 & 710 Sansom Street, Philadeiphla. Practic e # O iagnosis* Flinfs Practice of Medicine— Sixth Edition. A TREATISE ON THE PRINCIPLES AND PRACTICE of Medicine. Designed for the Use of Students and Practitioners of Medi- cine. By Austin Flint, M. D., LL. D., Professor of the Principles and Practice of Medicine and of Clinical Medicine in Bellevne Hospital Medical College, N. Y. Sixth edition, thoroughly revised and rewritten by the Author, assisted by William H. Welch, M. D., Professor of Pathology, Johns Hopkins University, Baltimore, and Austin Flint, Jr., M. i)., LL. D., Professor of Physiology, Bellevue Hospital Medical College, N. Y. In one very handsome octavo volume of 1160 pages, with illustrations. Cloth, 15.50; leather, $6.50. No text-book on the principles and prac- tice of medicine has ever met in this country with such general approval by medical stu- dents and practitioners as the work of Pro- fessor Flint. In all the medical colleges of the United States it is the favorite work upon Practice ; and, as we have stated before in alluding to it, there is no other medical work that can be so gene-ally found in the libra- ries of physicians. In every state and terri- tory of this vast country the book that will be most likely to be found in the office of a medical man, whether in city, town, village, or at some cross-roads, is JFlint's Practice. We make this statement to a considerable extent from personal observation, and it is the testimony also of others.— (7mci»na<» Medical News, October, 1886, Flint's Auscultation and Percussion— Fifth Edition. A MANUAL OF AUSCULTATION AND PERCUSSION; Of the Physical Diagnosis of Diseases of the Lungs and Heart, and of Thoracic Aneurism. By Austin Flint, M. D., LL. D., Professor of the Principles and Practice of Medicine in Bellevue Hospital Medical College, N. Y. Fifth edition. Edited by James C. Wilson, M. D., Lecturer on Physical Diagnosis in the Jefferson Medical College, Philadelphia. In one handsome royal 12mo. vol. of 274 pages, v^ith 12 illustrations. Cloth, $1.75. ite text-book with medical students. As stated by the editor, its vahie is to be dis- covered in the clearness and appropriateness of its style, the accuracy of its statements, its scientific method, and the practical treat- ment of subjects at once difficult and essen- tial to the student of medicine.— Cincmna^i The work has met with the favorable en- dorsement of the profession, a fifth edition being needed to meet the demand for it. Pro- fessor Flint's Practice of Medicine has raet with a success that has never been equalled by any other work of the kind in this coun- try. The one before us on Physical Diagno- sis seems also to have become a favor- Medical News^ February, 1891. Hartshorne's Essentials of Practice— 5th Edition. ESSENTIALS OF THE PRINCIPLES AND PRACTICE of Medicine. A Handbook for Students and Practitioners. By Henry Hartshorne, M. D., LL. D., Lately Professor of Hygiene in the tlniversity of Pennsylvania. Fifth edition, thoroughly revised and rewritten. In one royal 12mo. volume of 669 pages, with 144 illustrations. Cloth, $2.75. The Students' Quiz Series-||fvys^B«l!^i.TiE''?T LEA BROTHEftS & CO., 706, 708 & 710 Sansom Street, Philadelphia. Practice # Electricit\? # Diagnosis* Bristowe's Practice of Medicine— 7th Edition. A TREATISE ON THE SCIENCE AND PRACTICE OP Medicine. By John Syer Bristowe, M. D., LL. D., F. li. S., Senior Physician to and Lecturer on Medicine at St. Thomas' Hospital, London. Seventh edition. In one 8vo. vol. of 1325 pages. Cloth, $6. 50 ; leather, |7. 50. peared. It is a work that is built on a stable llie remarkable regularity with which new editions of this text-book make their appearance v. striking testimony to its ex- cellence and value. This, too, in spite of the numerous rivals for the favor of the student, which have been put forth within the sixteen years since Bristowe'a Medicine first ap- foundation, systematic, scientific, and prac- tical, containing the matured experience of a physician who has every claim to be con- sidered an authority, and composed in a style which attracts the practitioner as much as the student.— TAe Lancet, July 12, 1890. Fotliergill's Handbook of Treatment— 3d Edition. THE PRACTITIONER'S HANDBOOK OF TREATMENT ; Or, the Principles of Therapeutics. By J. Milner Fotiiergill, M.D., Edin., M. R. C. p., Lond., Physician to the City of London Hospital for Diseases of the Chest. Third edition. In one 8vo. volume of 661 pages. Cloth, $3.75; leather, $4.75. This is a wonderful book. If there be such a thing as "medicine made easy," this is the work to accomplish this result.— Vir- ginia Medical Monthly, June, 1887. We do not know a more readable, practical and useful work on the treatment of disease than the one we have now before \x^.— Pacific Medical and Surgical Journal, Oct. 1887. While the work should be attentively studied by every medical student, yet it is no less adapted to the wants of the experienced physician, who has been educated in his pro- fession with the impression from the begin- ning that the treatment of disease is entiiely empirical. There is no work in the English language in regard to which we are so im- pressed that physicians should both read and study as this work. — Cincinnati Medical News, June, 1887. It is an excellent practical work on thera- peutics, well arranged and clearly expressed, useful to the student and young practitioner, perhaps even to the o\6..— Dublin Journal of Medical Science, March, 1888. Bartholow's Medical Electricity— Third Edition. MEDICAL ELECTRICITY. A Practical Treatise on the Applications of Electricity to Medicine and Surgery. By Roberts Bar- THOLOW, A. M., M. D,, LL. D., Professor of Materia Medica and General Therapeutics in the Jefferson Medical College of Philadelphia, etc. Third edition. In one very handsome octavo volume of 308 pages, with 110 illustrations. Cloth, $2.50. The fact that this work has reached its third edition in six years, and that it has been kept fully abreast with the increasing use and knowledge of electricity, demon- strates its claim to be considered a practical treatise of tried value to the profession. The matter added to the present edition embraces the most recent advances in electrical treat- ment. The illustrations are abundant and clear, and the work constitutes a full, clear and concise manual well adapted to the needs of both student and practitioner.— The Medical News, May 14, 1887. Broadbent on the Pulse. THE PULSE. By AV. H. Broadbent, M. D., F. R. C. P., Lect- urer on Medicine at St. Mary's Hospital, London. In one 12mo. volume of 312 pages. Cloth, |1.75. See Series of Clinieal Manuals, at end. LEA BROTHERS & CO., 706, 708 & 7fO^Sansom Street Philadelphia. Practice of /Vledicine ^ Throat and Nose. Lyman's Practice of Medicine. A TEXT BOOK OF THE PRINCIPLES AND PRACTICE of Medicine, For the Use of Medical Students and Practitioners. By Henry M. Lyman, M. D., Professor of the Principles and Practice of Medicine in Rush Medical College, Chicago. In one very handsome royal octavo volume of 926 pages, with 180 illus. Cloth, $4,75, leather. |5.75. This is an excellent treatise on the prac- tice of medicine, written by one who is not only familiar with his subject, but who has also learned through practical experience in teaching, what are the needs of the student, and how to present the facts to his mind in the most readily assimilable form. The reader is not confused by having presented to him a variety of different methods of treat- ment, among which he is left to choose the one most easy of execution, but the author de- scribes the one which is in his judgment the best. What the student should be taught is the one most approved method of treatment. We have spoken of the work as one for the student, and this because the author occu- pies so prominent a position as a teacher; but we would not be understood that it is adapted only for students. There is many a practitioner to whom this work will be of great use. He will find here each subject presented in its latest aspect. The practical and busy man who wants to ascertain in a short time all the necessary facts concerning the pathology or treatment of any disease, will find here a safe and convenient guide. —Medical Record^ October 22, 1892. Whitla's Dictionary of Treatment. A DICTIONARY OF TREATMENT ; OR THERAPEUTIC Index, including Medical and Surgical Therapeutics. By William Whitla, M. D., Professor of Materia Medica and Therapeutics in the Queen's College, Belfast. Kevised and adapted to the United States Phar- macopoeia. In one square, octavo volume of 917 pages. Cloth, $4.00. examined. The book abounds with useful, practical hints and suggestions, and the younger practitioner will find in it exactly the help he so often needs in treatment The most experienced members of the profession may usefully consult its pages for the pur- pose of learning what is really trustworthy in the later therapeutic developments.— T^e Glasgow Medical Journal^ April, 1892, The several diseased conditions are ar- ranged in alphabetical order, and the methods— medical, surgical, dietetic and cli- matic—by which they may be met, consid- ered. On every page we find clear and de- tailed directions for treatment, supported by the author's personal authority and ex- perience, whilst the recommendations of other competent observers are also critically Seiler on the Throat and Nose-^^^lfs^^^R^E^kTy^^ A HANDBOOK OF DIAGNOSIS AND TREATMENT OF Diseases of the Throat, Nose and Naso-Pharynx. By Carl Seiler, M. D., Lecturer on Laryngoscopy in the University of Pennsylvania. Fourth edition. In one handsome royal 12mo, volume of about 400 pages, with 107 illustrations and 2 colored plates. Cloth, |2.25. A notice of the previous edition is appended. The object of the volume is to serve as a guide to students of laryngology in acquir- ing the skill requisite to the successful diag- nosis and treatment of diseases of the larynx and naso-pharynx. The author has omitted all purely theoretical considerations, and lias discussed only points of practical impor- tance as concisely as possible. The work may be used as a ready book of reference.— The Cincinnati Medical News. Jan. 1889. EYE, EAR. THROAT AND NOSE, $1. SEE PAGEl The Students' Quiz Series- LEA BROTHERS & CO., 706,708 & 710 Sansom Street Philadelphia. Oiagiiosis ^ Urinary? & ^cnal & Treatment Mnsser's Medical Diagnosis. In Press. A PRACTICAL TREATISE ON MEDICAL DIAGNOSIS. For the Use of Students and Practitioners. By John H. Musser, M. D., Assistant Professor of Clinical Medicine, University of Pennsylvania, Phila- delphia. In one octavo volume of about 650 pages. Teo on Food in Health and Disease. FOOD IN HEALTH AND DISEASE. By I. Burney Yeo, M. D., F. E. C. P., Professor of Clinical Therapeutics in King's College, London. In one 12mo. volume of 590 pages. Cloth, $2.00. Series of Clinical Manuals. Dr. Yeo supplies in a compact form nearly all that the practitioner requires to know on the subject of diet. The work is divided into two parts— food in health and food in disease. Dr. Yeo has gathered together from all quarters an immense amount of useful information within a comparatively- small compass, and he has arranged and digested his materials with skill for the use of the practitioner. We have seldom seen a book which more thoroughly realizes the object for which it was written than this little work of Dr. Yeo.— British Medical Journal, Feb. 8, 1890. Teo's Medical Treatment— Jnst Ready. A MANUAL OF MEDICAL TREATMENT OR CLINICAL Therapeutics. By I. Bueney Yeo, M. D., F. R. C. P., Professor of Clin- ical Therapeutics in King's College, London. In two 12mo. volumes, containing 1275 pages, with illustrations. Cloth, |5.50. Roberts on Urinary and Renal Diseases— 4th Ed. A PRACTICAL TREATISE ON URINARY AND RENAL Diseases, Including Urinary Deposits. By Sm William Roberts, M. D., Lecturer on Medicine in the Manchester School of Medicine, etc. Fourth American from the fourth London edition. In one handsome octavo volume of 609 pages, with 81 illustrations. Cloth, $3.50. is also either the text-book or the reference- book in most of the medical colleges of the country that have a special chair for renal and urinary diseases. — Virginia Medical The constant aim of the author has been to make the book a valuable guide to the clinical student. It is doubtless the most generally accepted standard work. We do not see how any general practitioner of med- icine can afford to be without the book. It Monthly, November, 1885. Tbe Tear-Book of Treatment for 1893. A COMPREHENSIVE AND CRITICAL REVIEW FOR Practitioners of Medicine and Surgery. In one 12mo. volume of 500 pages. Cloth, |1.50 For special commutations with periodicals see page 32. With comparatively little labor, the busy practitioner gets the gist of medical litera- ture the world over. Every branch of medi- cine is covered— new remedies, old ones with new applications, new operations, all receiv- ing attention.— iJ/edica^ Record. THE YEAR-BOOKS OF TREATMENT for 1891 and 1892 ; 485 pages, each $1.50. The Year-Books for 1886 and 1887, 320-341 pages, each, $1.25. LEA BROTHERS & CO., 706, 708 & 710 Sansom Street, Philadelphia. Pathologx? & Histologx^ & l^act^r\oloQ^. Gibbes' Pathology and Histology. PRACTICAL PATHOLOGY AND MORBID HISTOLOGY. By Heneage Gibbes, M. D., Professor of Pathology in the University of Michigan, Medical Department. In one very handsome octavo volume of 314 pages, with 60 illustrations, mostly photographic. Cloth, $2.75. are particularly accurate and impart to the The important subject is brought fully up with the most recent advances. All the de- tails of practical work in this department are given in the most lucid manner, so that as a guide it will prove exceedingly valuable. The value of the work is greatly enhanced by the numerous illustrations of morbid tissues displayed. These photo-engravings work advantages not possessed by any other method of illustration. The section on Prac- tical Bacteriology contains all the instruction necessary. It is a model of the kind, and deserves the fullest patronage of the medical- student world,— Nashville Journal of Medi- cine and Surgery^ October, 1891. Abbott's Bacteriology. THE PRINCIPLES OF BACTERIOLOGY. A Practical Manual for Students and Physicians. By A. C. Abbott, M. D., First Assis- tant, Laboratory of Hygiene, University of Pennsylvania, Philadelphia. In one 12mo. volume of 259 pages, with 32 illustrations. Cloth, $2. CO. Now that practical bacteriology forms a specific portion of the medical student's labors, there will be a growing call for man- uals of the science. In the book before us instruction is afforded in all laboratory manipulations, and sterilization, culture media, inoculations, and staining, are all dealt with in a careful and specific manner. No college of medicine will be known for such that does not in the next few years provide for teaching bacteriology to its stu- dents, — The FhyUcian and Surgeon^ Mar. '92. Klein's Histology— Fourth Edition. ELEMENTS OF HISTOLOGY. By E. Klein, M. D., F. R. S., Joint Lecturer on General Anatomy and Physiology in the Medical School of St. Bartholomew's Hospital, London. Fourth edition. In one 12mo. volume of 376 pages, with 194 illustrations. Limp cloth, |1.75. See Stif.- dents' Series of Manuals, at end. Crisp, concise, straightforward, his descrip- tions proceed from animal protoplasm and the simple cell, to the histology of every organ of the human body. The author gives just that information which the intelligent student of anatomy wants and is justified in expecting, but which he is often denied. The illustrations are as excellent as is the matter they Sidoin.— The 3Iictoscope, January, 1890. Green's Pathology and Morbid Anatomy— 7tli Ed. PATHOLOGY AND MORBID ANATOMY. By T. Henry Green, M. D., Lecturer on Pathology and Morbid Anatomy at Charing Cross Hospital Medical School, London. Sixth American from the seventh revised English edition. Octavo, 539 pages, 167 engravings. Cloth, $2.75. This book presents the subject in so satis- ^' "^ '"""'' '"^ *^ '"^'^ «'+.-" «* factory a manner as to be not only favorably received by the medical profession, but to be at once placed in the enviable position of a text-book in all medical schools.— TAe Cincinnati Lancet Clinic, Oct. 19, 1889. The Students' Quiz Series-«^TA'cTlS^$t''§ SEE P. 1. LEA BROTHERS & CO , 706, 708 & 710 Sansom Street, Philadelphia. PathoL ^ Histol. m gacterioL— (Cont.) Senn's Surgical Bacteriology— Second Edition. SURGICAL BACTERIOLOGY. By Nicholas Senn, M.D., Ph.D., Professor ol' Surgery in Kiish Medical College, Chicago. New (secoud) edition. In one handsome octavo of 268 pages, with 13 plates, of which 10 are colored, and 9 engravings. Cloth, |2.00. The book is valuable to the student, but its chief value lies in the fact that such a compil- ation makes it possible for the busy practi- tioner, whose time for reading is limited and whose sources of information are often few, to become conversant with the most modern and advanced ideas in surgical patholotfy, which have "laid the foundation for the wonderful achievements of modern surgery." —Annals of Surgery, March, 1892. Payne's General Pathology. A MANUAL OF GENERAL PATHOLOGY. Designed as an Introduction to the Practice of Medicine. By Joseph F. Payne, M. D., F. R. C. P., Senior Assistant Physician and Lecturer on Pathological Anat- omy, St. Thomas' Hospital, London. Octavo of 524 pages, with 152 illus- trations, and a colored plate. Cloth, $3.50. The work has our heartiest commendation. Whether regarded as a text-book for the student, or as a work of reference for the scientific practitioner, it has no equal in our language on the subject of which it treats. —The American Journal of the Medical Sciences, February, 1889. Coats' Pathology. A TREATISE ON PATHOLOGY. By Joseph Coats, M. D., F. F. P. S. , Pathologist to the Glasgow Western Infirmary. In one octavo volume of 829 pages, with 339 illus. Cloth, $5.50; leather, $6.50. The author, owing to his large experience as a practical pathologist, has written a book which is as instructive as it is complete, being brought up to the latest advances in that science. The plan of the book is one that will meet with universal ap- proval. We commend the work as fill- ing the wants of the practitioner and the student. The illustrations are mostly new and are well executed. A novel feature, and one at the same lime very useful, is the arrangement of the index, whereby the derivation of all technical terms is given, so that this portion of the work is, as it were, a medical lexicon in itself.— iVew; Orleans Med. and Surg. Journal, Feb. 1884. Schafer's Histology— Second Edition. THE ESSENTIALS OF HISTOLOGY. By Edward A. ScHAFER, F. R. S., Jodrell Professor of Physiology in University College, London. New (second) edition. In one octavo volume of 311 pages, with 325 illustrations. Cloth, |3.00. This work now appears in its third edition, revised and enlarged. It has been used for some time past as the text-book on its subject in a large number of colleges, and is so well and favorably known by teachers and stu- dents of histology that a discussion of the book seems unnecessary. The matter is systematically arranged into forty-five les- sons for the careful study of the minute anatomy of the various tissues of the body. Unimportant details are omitted, the matter is clearly and concisely presented, and the large number of cuts employed to illustrate the text recommend this book to all inter- ested in histology. An appendix containing directions for the preparation of sections for microscopic study is added.— t/wtvem/y Med' teal Magaziney January, 1893. LEA BROTHERS & CO., 706, 70^ S^ 710 Sansom Street, Philadelphia. Nerves # E\?e # Ear m Throat # Nose. Gray on Nervons and Mental Diseases. A PRACTICAL TREATISE ON NERVOUS AND MEN- tal Diseases. By Landon Caktek Gray, M. D., Professor of Diseases of the Mind and Nervous System in the New York Polyclinic. In one 8vo. volume of 681 pages, with 168 illus. Cloth, $4.50; leather, $5.50. The symptomatology and etiology are very thorough and complete without being in the least verbose. The treatment of each disease is considered in all its details, and the useful- ness of the most recent remedies demon- strated. The treatise on mental diseases is by no means the least important feature of the work. The student is not confused by a bewildering and interminable classifi- cation; on the contrary, Dr. Gray has at- tempted to simplify this subject, with a suc- cess which, it is hoped, other authors will not be slow to recognize and imitate. The glossary at the ena of the volume will mate- rially assist those who are not conversant with neurological terms to a thorough com- prehension ol the text. — Journal of Nervoits and Mental Disease, Dec, 1892. Norris & Oliver's Ophthalmology— Jnst Ready. A TEXT-BOOK OF OPHTHALMOLOGY. By William F. NoRKis, M. D., Professor of Ophthalmology in the Medical Department of the University of Pennsylvania, and Charles A. Oliver, M. D., Surgeon to Wills' Eye Hospital, Phila. In one octavo vol. of 641 pp., with 357 beau- tiful engrav. and 5 col. plates, test-types, etc. Cloth, $5.00 ; leather, $6.00. It is safe to say that in the rich literature of Ophthalmology, no volume will be found which will give so clear and satisfactory an exposition of its subject in all practical bearings. Its exceptionally profuse and handsome series of illustrations will aid materially in constituting it a most satisfactory work for the student, practitioner and specialist. Nettleship on the Eye— Fifth Edition. DISEASES OF THE EYE. By Edward Nettleship, F. R. C. S., Ophthalmic Surgeon at St. Thomas' Hospital, London. Fourth American from the fifth English edition, thoroughly revised. In one 12mo. volume of 500 pages, with 164 illus., selections from Snellen's test-types and formulae, and a colored plate for detecting color-blindness. Cloth $2.00. color-blindness tests and a collection of for- Four large American editions testify to the fact that it is a favorite text-book in Ameri- can colleges as well as to the extent of its use among practitioners in general and special branches. Its popularity as a refer- ence-book is due to the practical nature of its text and to the inclusion of text-types, mulse. It is safe to predict that with the extended scope noted in its title, this handy volume will become more than ever a favorite with all classes of readers.— Pac?/ic Medical Journal, December, 1890. Bnrnett'on the Ear— Second Edition. THE EAR; ITS ANATOMY, PHYSIOLOGY AND Dis- eases. A Practical Treatise for the Use of Medical Students and Practi- tioners. By Charles H. Burnett, A. M., M. D , Professor of Otology in the Philadelphia Polyclinic. Second edition. In one handsome octavo volume of 580 pages, with 107 illustrations. Cloth, |4.00j leather, |5.00. Students' Quiz Serie s— ^^^' ^^^' IHV^g^V '"'^^' *'• LEA BROTHERS & CO., 706, 708 & 710 Sansom Street, Philadelphia. Surgery- # Ophthal. ^ NeuroL— (Cont .) Holmes' Treatise on Surgery— Fifth Edition. A TREATISE ON SURGERY; ITS PRINCIPLES AND Practice. By Timothy Holmes, M. A., Surgeon and Lecturer on Surgery at St. George's Hospital, London. From the fifth English edition, edited by T. Pickering Pick, F. R. C. S. In one octavo volume of 997 pages, with 428 illustrations. Cloth, |6.00 ; leather, $7.00. The work is one of the bsst text-books for standard text-book on the principles and students and practitioners who have not the time to wade through the exhaustive systems and encylopaedias of surgery. — Atlanta Medi- cal and SurgicalJournal, August, 1889. This work, which has now arrived at its fifth edition, still maintains its position as a practice of surgery. Mr. Pick has performed his part of the work with rare judgment and skill. The book contains many original illustrations which add much to its merits as a whole.— The Medical Record, Nov. 2, 1889, Carter & Frost's Ophthalmic Surgery. OPHTHALMIC SURGERY. By R. Brudenell Carter, F. R. C. S., Lecturer on Ophthalmic Surgery at St. George's Hospital, Lon- don, and W. Adams Frost, F. R. C. S. , Joint Lecturer on Ophthalmic Surgery at St. George's Hospital, London. In one 12mo. volume of 559 pages, with 91 engravings, color-blindness test, test-types and dots and appendix of formulse. Cloth, $2.25. See Series of Clinical Manuals, sit end. This work belongs to the series of clinical manuals for practitioners and students of medicine, which Messrs. Lea Brothers & Co. have in process of publication. The works eohiprising this series, as we have mentioned before, are made in size, arrangement, etc., exceedingly convenient for the use of stu- dents in attendance upon lectures, and for reference by practitioners of medicine. We know of no work upon ophthalmic diseases so well adapted for reference by physicians and for use of students in attendance upon lect\Jires.—Cincin7iati Med. News, Aprils 1888. Ross on Nervous Diseases. A HANDBOOK ON DISEASES OF THE NERVOUS System. By James Ross, M. D., F. R. C. P., LL.D., Senior Assistant Physician to the Manchester Royal Infirmary. In one octavo volume of 725 pages, with 184 illustrations. Cloth, |4.50 ; leather, $5.50. This admirable work is intended for stu- dents of medicine and for such medical men as have no time for lengthy treatises. Dr. Ross holds such a high scientific position that any writings which bear his name are naturally expected to have the impress of a powerful intellect. In every part this hand- book merits the highest praise, and will no doubt be found of the greatest value to the student as well as to the prsictitioner.— Edin- burgh Med. Journal, JsiJi. 1887. Hamilton on Nervous Diseases— Second Edition. NERVOUS DISEASES ; Their Description and Treatment. By Allan McLane Hamilton, M. D., Attending Physician at the Hospital for Epileptics and Paralytics, Blackwell's Island, N. Y. Second edition, , thoroughly revised and rewritten. In one octavo volume of 598 pages, ' with 72 illustrations. Cloth, $4.00. We do not well see how the student or I author claims for it— "a manual for students practitioner can afford to be without this and practitioners."— Virginia Med. Monthly^ book. It is in the highest sense what the | May, 1882. UA BROTHERS & CO., 706, 708 & 710 Sansom Street Philadelphia, Surg, — (Cont.) # /Vlinor Surg. & ^atidaQinQ. Roberts' Modern Surgery. THE PRINCIPLES AND PRACTICE OP MODERN Surgery. For the Use of Students and Practitioners of Medicine and Sur- gery. By John B. Roberts, M. D., Professor of Anatomy and Surgery in the Philadelphia Polyclinic. Professor of the Principles and Practice of Surgery in the Woman's Medical College of Pennsylvania. In one octavo volume of 780 pages, with 501 illustrations. Cloth, |4.50 ; leather, $5.50. It has been the effort of the author to pre- paie a volume that will be in every respect a thoroughly good surgical text-book. Being a teacher of surgery both in college and hospital, he understands just what sort of a text-book a student needs from which, with the aid of lectures, to acquire a knowledge of surgery ; and he has prepared his manual in accordance with this knowledge. While he has drawn upon his own experience, he has consulted, as he states, the latest literature of all kinds bearing upon his specialty. Though there are many works upon surgery of great excellence that have been before the profession for some time, yet there are none of a more practical character than that of Dr. Roberts. It is filled with illustrations that will aid much in elucidating the text- ile Cincinnati Medical News, October, 1890. Ashhnrst's Surgery— Fifth Edition. THE PRINCIPLES AND PRACTICE OF SURGERY. By John Ashhurst, Jr., M. D., Barton Professor of Surgery and Clinical Sur- gery in the University of Pennsylvania. Fifth edition, enlarged and thor- oughly revised. In one large and handsome octavo volume of 1144 pages, with 642 illustrations. Cloth, $6.00 ; leather, |7.00. A complete and mast excellent work on surgery. It is only necessary to examine it to see at once its excellence and real merit either as text-book for the student or a guide for the general practitioner. It fully con- siders in detail every surgical injury and disease to which the body is liable, and every advance in surgery worth noting is to be found in its proper place. It is unquestion- ably the best and most complete single vol- ume on surgery in the English language, and cannot but receive that continued ap- preciation which its merits justly demand.— Southern Practitioner, February, 1890. Wharton's Minor Surgery and Bandaging. MINOR SURGERY AND BANDAGING. By Henry R. Wharton, M. D., Demonstrator of Surgery and Lecturer on Surgical Dis- eases of Children in the University of Pennsylvania. In one very handsome 12mo. volume of 498 pages, with 403 engravings, many being photo- graphic. Cloth, 13.00. Dr. Wharton has written a book especially designed for students and younger prac- titioners, superior in many respects to others on this subject. The portions of it devoted to bandaging and fracture-dressing are par- ticularly good. Full and accurate verbal descriptions of the mode of applying all the important bandages, and of the best modern methods of treating and dressing fractures and dislocations, are supplemented and ren- dered still more valuable by a number of excellent illustrations, most of them new. These have been photographed from life. and they combine the advantages of clear- ness of outline and accuracy in portraying the various turns of the bandages they repre- sent. Thus the methods of application of the various dressings are rendered mot e easy of apprehension than by verbal description. The part of the work devoted to a descrip- tion of the different substances and ma- terials used in antiseptic dressings and operations and the mode of their preparation seems also excellent,— Medical News, Novem- ber 28, 1891. LEA BROTHERS & CO., 706, 708 ^ Syri^s of /Vlanuals> Smith on Children— Seventh Edition. A TREATISE ON THE DISEASES OF INFANCY AND Childhood. By J. Lewis Smith, M. D., Clinical Professor of Diseases of Children in BellevueHosp. Med. Col., N. Y. Seventh edition, thoroughly re- vised and rewritten. Octavo, 881 pages, 51illus. Cloth, $4.50; leather, $5.50. edition we note a variety of changes in ac- We have always considered Dr. Smith's book as one of the very best on the subject. It ha.s always been practical— a field book, theoretical where theory has been deduced from practical experience. The very prac- tical character of this book has always ap- pealed to us. Ono seldom fails to find here a practical suggestion after search in other works has been in vain. In the seventh cordance with the progress of the times. It still stands foremost as the American text- book. Its advice is always conservative and thorough, and the evidence of research has long since placed its author in the front rank of medical teachers. — American Journal of the Medical Sciences, Dec. 1891. Taylor's Medical Jurisprndence— ^^^tJII^^^e^a^dy^^^- A MANUAL OF MEDICAL JURISPRUDENCE. By Alfred S. Taylor, M. D., Lecturer on Medical Jurisprudence and Chem- istry in Guy's Hospital, London. New American from the twelfth English edition. Thoroughly revised by Clark Bell, Esq., of the New York Bar. In one octavo vol. of 787 pages, with 56 illus. Cloth, $4.50; leather, $5.50. The merits of this work are well recog- nized, audits value as a standard text-book for medical instruction and as a trustworthy guide in medico-legal emergencies is fully appreciated. It is enough, to assert with con- fidence that as 4 manual upon the subj ect of which it treats it is not excelled by any other work on medical jurisprudence in the English language. If the medical practi- tioner is obliged to limit his literature upon legal medicine to a single volume, he will not make a mistake if he gives his preference to this eleventh American edition.— ^05/on Medical and Surgical Journal, Jan. 5, 1893. Students' Series of Manuals. A Series of Fifteen Manuals, for the Use of Students and Practitioners of Medicine and Surgery, written by eminent Teachers or Examiners, and issued in pocket-size 12mo. vol- umes of 800-540 pages, richly illustrated and at alow price. The following volumes are now ready: ItU ff's Manual of Chemistry, $2.00; Hermas^s First Lines in Midwifery, $1.25; Treves' Manual of Surgery, hj various writers, in three volumes, per set, $6.00; Bell's Comparative Anatomy and Physiology, $2.00; Gould's Surgical Diagnosis, $2.00; Robert- son's Physiological Physics, $2.00 ; Bruce's Materia Medica and Therapeutics (4th edition), $1.50 ; Power's Human Physiology (2d edition), $1.50; Clarke and Lockv^^ood's Dissectors' Manual, $L50; Ralfe's Clinical Chemistry, $1.50; Treves' Surgical Applied Anatomy, $2.00; Ff.ppkr's Surgical Pathology, $2.00; and Ki^FHia^s Elements of Histology {Uh edition), $1.75. For detailed Catalogue, address the Publishers. Series of Clinical Manuals. A collection of authoritative monographs on important clinical subjects in a cheap and f>ortable form. The volumes contain about 550 pages and are freely illustrated by chromo- ithographs and woodcuts. The following volumes are now ready : Yeo on Food in Health and Disease, $2.00 ; Broadbent on the Pulse, $1.75 ; Carter & Frost's Ophthalmic Surgery, $2.25; Hutchinson on Syphilis, $2.25'; Marsh on the Joints, $2 00; Owen on Surgical Diseases of Children, $2,00; Morris on Surgical Diseases of the Kidneys, $^2.25; Pick on Fractures and Dislocations. $2,00; Butlin on the Tongue, $3.50; Treves on Intestinal Obstruction, $2.00; and Savage on Insanity and Allied Neuroses, $2.00. For detailed Cata- logue, address the Publishers. The Students' Quiz Series — Diseases of children, $1. see p. 1. LEA BROTHERS & CO., 706, 708