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 JUL 1 "^ 1981 
 
A MANUAL 
 
 STRUCTURAL BOTANY 
 
 AN INTEODUCTOEY TEXT-BOOK FOR STUDENTS 
 OF SCIENCE AND PHARMACY 
 
 ^ / 
 
 BY 
 
 HENRY H. RUSBY, M.D. 
 
 PROFESSOR OF MATERIA MEDICA IN THE COLLEGE OF PHARMACY OF THE CITY OF NEW YORK (COLr.MBI^ 
 
 university) ; chairman op the scientific DIRECTORS OF THE NEW YORK BOTANICAL 
 
 gardens; president of the TORREY BOTANICAL CLUB; PHARMACOGNOSIST 
 
 OF THE UNITED STATES DEPARTMENT OF AGRICULTURE; MEMBER 
 
 OF THE COMMITTEE FOR THE REVISION OF THE UNITED 
 
 STATES PHARMACOPOEIA SINCE 1890 
 
 WITH 599 ILLUSTRATIONS 
 
 LEA & FEBIGER 
 
 PHILADELPHIA AND NEW YORK 
 1911 
 
Entered according to the Act of Congress, in the year 1911, by 
 
 LEA & FEBIGER, 
 in the Office of the Librarian of Congress. All rights reserved. 
 
PREFACE 
 
 This volume, which is a condensed but fairly complete introduction 
 to botany, and is suitable as a text-book for academic or collegiate 
 students, has been written with special reference to the needs of the 
 first year student of pharmacy, as a preparation for his second year 
 work in pharmacognosy. It may, therefore, be regarded as an intro- 
 duction to pharmacognosy, as well as to general botany. It will be 
 followed by a companion volume on Commercial Pharmacognosy. 
 
 Pharmacognosy may be defined as the art of identifying, valuing, 
 and selecting drugs of vegetable and animal origin. It is, therefore, 
 ^not a distinct science, although various sciences may be employed in 
 its practice. In such operations as taking specific gravity, making 
 microscopical measurements and determining the characters of crystals, 
 physics is utilized. In making qualitative tests of identity and purity 
 and determining the percentages of constituents, chemistry is involved. 
 In determining the structural characters of plant and animal bodies, 
 botanical and zoological knowledge is necessary. In determining the 
 value of drugs of which the purity and strength cannot be estimated 
 by any of these methods, we may have recourse to physiological tests 
 on animals, or pharmaco-dynamics. 
 
 It is thus apparent that the entire field of pharmacognosy is very 
 broad and that its complete working involves varied classes of labora- 
 tory operations. The extent and complexity of detail that have 
 become necessary in these operations have required their consideration 
 in separate departments of the pharmaceutical curriculum, so that such 
 branches as physical and chemical testing and pharmaceutical assaying 
 have been established. 
 
 The number of drugs of animal origin in general use has become so 
 small that the study of zoology is no longer deemed essential, and it is 
 left to botany to contribute by far the greater portion of the instruction 
 now deemed essential as a preparation for the study of pharmacognosy. 
 Manifestly, a knowledge of structural botany is the only scientific 
 basis for the examination of the i)lant body. 
 
 
 
VI PREFACE 
 
 Since a correct knowledge of the structural relations of the plant- 
 parts to one another can scarcely be gained without some knowledge 
 of their uses in the economy of the plant, it follows that at least the 
 elementary facts of plant-physiology must be considered in connection 
 with its anatomy. 
 
 The parts of plants which are used as drugs may come to us either 
 in their entire condition or in such large fragments as to be capable 
 of examination with the naked eye, or in the crushed or powdered 
 condition, when their examination requires the aid of the compound 
 microscope. Even in the case of the whole drug, the examination will 
 frequently call for the aid of the microscope in determining difficult 
 questions of identity or quality. 
 
 Commercial Pharmacognosy may be defined as the application of 
 pharmacognosy to ordinary commercial operations. It includes the 
 examination of crude drugs by growers, collectors, traders, brokers, 
 importers, and ordinary purchasers for pharmaceutical purposes. 
 All such persons should be qualified to subject their drugs to the 
 most complete and minute examination, or should employ someone 
 who is so qualified; but, as a matter of fact, this is probably not 
 true in more than one case in a hundred, though happily this propor- 
 tion is steadily increasing. In all others, dependence is wholly upon 
 examinations made with the naked eye, or at most with a pocket lens. 
 The work on Commercial Pharmacognos}" will be designed for the use 
 of all such persons in their commercial operations with drugs. It will 
 deal with the commercial aspects of all drugs found in commerce, their 
 identity, varieties, grades, and qualities, their substitutes, adulterants, 
 and imperfections, their trade designations and relative values. 
 Although designed for use as a text-book, it will be especially valuable 
 in its commercial adaptations. 
 
 In view of the totally different methods of examination involved, 
 and the apparatus and other facilities required, the subjects of 
 vegetable histology and of microscopical methods and technique are 
 omitted from the present work, its object being to teach the student 
 all that it is possible for him to do in the examination of drugs with 
 the naked eye or with the pocket lens. 
 
 H. H. R. 
 
CONTENTS 
 
 CHAPTER I 
 Fundamental Considerations 17 
 
 CHAPTER II 
 
 Anthology; General Nature of the Flower 23 
 
 CHAPTER III 
 Laws of Floral Structure 36 
 
 CHAPTER IV 
 The Perigone 50 
 
 CHAPTER V 
 The Androecium 62 
 
 CHAPTER VI 
 The Gynaecium 70 
 
 CHAPTER VII 
 The Torus and Disk 81 
 
 CHAPTER VIII 
 Dissection and Analysis of Flowers 86 
 
 CHAPTER IX 
 Pollination and Fertilization 90 
 
 CHAPTER X 
 Carpology; Functions and Structure of the Fruit 102 
 
 CHAPTER XI 
 Classification of Fruits 116 
 
Vlll CONTENTS 
 
 CHAPTER XII 
 The Seed 127 
 
 CHAPTER XIII 
 General Structure of Root andStem . 136 
 
 CHAPTER XIV 
 Extensions and Appendages of the Stem 15;j 
 
 CHAPTER XV 
 
 Classification OF Roots AND Stems 158 
 
 CHAPTER XVI 
 The Leaf 170 
 
 CHAPTER XVII 
 Anthotaxy 199 
 
 CHAPTER XVIII 
 Cryptogams 207 
 
 CHAPTER XIX 
 Botanical Classification and Analysis 21 S 
 
 CHAPTER XX 
 Botanical Nomenclature 222 
 
 CHAPTER XXI 
 The Collection and Preservation of Botanical Specimens .... 226 
 
INTRODUCTION TO PHARMACOGNOSY. 
 STRUCTURAL AND DESCRIPTIVE BOTANY 
 
 CHAPTER I 
 
 FUNDAMENTAL CONSIDERATIONS 
 
 Organic Bodies, Organs and Functions. — Living bodies differ from 
 those wliich are lifeless in their al)ility to grow by converting into their 
 own substance extraneous and dissimilar substances, as seen in the use 
 of carbonic acid in the ]:)roduction of starch and cellulose. This process 
 is called Assimilation. They consist also of more or less distinct parts, 
 each of which performs special work differing from that performed by 
 the other parts. These parts are called Organs or ]\Iembers, and the 
 special work which each organ performs is called its Function. Living 
 bodies are, therefore, designated as Organic Bodies and the part of 
 nature composed of them the Organic Kingdom. The term "organic 
 body" is usually preferable to "living body," as it applies equally well 
 to a body in which life has ceased to exist. A third important char- 
 acteristic of living bodies which may be mentioned is their power to give 
 origin to other independent living bodies, which, separating from their 
 parent, or remaining attached thereto, grow into a resemblance to it. 
 That is, they possess the power of Reproduction. 
 
 Organic Matter. — The assimilated matter of organic bodies is called 
 Organic Matter. Organic matter may be living, as cytoplasm, or lifeless, 
 as starch. It may, as in the case p/ the starch, be prepared for future 
 use as food, or be for the construction of tissue, as in the case of cellu- 
 lose, or it may exist as disassimilated matter resulting from the per- 
 formance of function, as the poisonous ptomaines of bacteria. The 
 latter may still be of some service in the i)lant economy, as are volatile 
 oils, or, perhaps, be entirely useless. 
 
 Plants and Animals. — Organic bodies are of two kinds — ^\>getable 
 and Animal — and are respectively denominated Plants and Animals. 
 
 Biology. — The study of the organic kingdom constitutes Biology. 
 
 Anatomy. — Biology in attention to the structure of bodies is Anatom}'. 
 
 f ROPERTT UBRAIf 
 
 r. ir 
 
18 FUNDAMENTAL CONSIDERATIONS 
 
 Physiology. — Biology in attention to functions is Physiology. We 
 have therefore both animal and plant anatomy, and animal and plant 
 physiology. 
 
 Botany. — Biology relating to plants is Botany. 
 
 Gross and Minute Anatomy. — Owing to the totally different methods 
 of examination employed in the two cases, it becomes of the greatest 
 convenience to divide anatomy, in practice, into two parts. That part 
 depending upon observations which can be pursued without the aid of 
 the compound microscope is knowai as Gross Anatomy. That which 
 requires such aid is Minute Anatomy, or Histology. 
 
 Microscopical Botany. — Applied to botany, the latter is commonly 
 known as Microscopical Botany, a term which, though incongruous, 
 possesses the excellent merit of being highly convenient and generally 
 expressive. 
 
 As the study of botany involves the use of physics and chemistry* 
 it is apparent that when so applied they become parts of botany, just 
 as botany becomes a part of physics or chemistry when applied in the 
 pursuit of those branches. The propriety of such terms as "chemical 
 botany" or "botanical chemistry" is thus explained. 
 
 Departments of Botany. — The departments of botany, and the manner 
 in which one may arise from the necessities of another and contribute 
 to it, may be illustrated as follows: 
 
 Systematic Botany. — It being understood that no plants are now in 
 existence which existed in the beginning, all having originated through 
 changes effected in some manner in those which formerly existed, one 
 of the great objects of botanical study is to ascertain the genetic rela- 
 tionships which exist between plants and to constitute such a systematic 
 arrangement of them as shall, so far as practicable, indicate the lines 
 and order of their development from others, that is, of their Phylogeny, 
 This department constitutes Systematic Botany. 
 
 Structural Botany. — Since such classification is based chiefly upon 
 structure, it is necessary that there should be a department known as 
 Structural Botany. 
 
 Physiological Botany. — Before the facts ascertained by the struc- 
 tural botanist can be utilized in classification, it is necessary that the 
 relative ranks of the structural characteristics should be determined. 
 Of any two structural characteristics, that which was first developed, 
 or is the older in creation, should form the basis of the primary division 
 of the group, the other of a subdivision. In ascertaining such relative 
 ranks, a consideration of the uses of the several characters is of great 
 
MEDICAL BOTANY 19 
 
 value, so that Physiological Botany or AVgetable Physiology is brought 
 into service. 
 
 Organography. — When structural botany has for its object merely the 
 determination of the organs as they exist, it becomes Organography. 
 
 Organogeny or Morphology. — When such object is to determine the 
 development of organs through the transformations of others, as of a 
 petal from a leaf, or a tendril from a branch, it becomes Organogeny or 
 Morphology. 
 
 Homologies and Analogies. — The ancestral organ and its developed 
 product are called Homologues of each other, and an Homology or 
 Affinity is said to exist between them. For example, the leaf of a plant, 
 and the petal of its flower, which we assume to have developed through 
 the modification of the leaf, are homologues of one another. When they 
 are only similar, without any genetic relationship, they are Analogues 
 of each other, and Analogy exists between them. Morphology might, 
 therefore, be defined as the stud}^ of homologies. 
 
 Anthology and Carpology. — As classification has been based very 
 largely upon flower structure and fruit structure, the study of these, 
 respectively, has been dignified by the titles Anthology and Carpology. 
 
 Phytography. — The description of plants in such manner that they 
 can be recognized therefrom is called Descriptive Botany or Phytog- 
 raphy. 
 
 Other Departments. — Botany has also numerous departments depend- 
 ing upon the class of plants under study, as Phanerogamic Botany, the 
 botany of flowering plants; Cryptogamic Botany, that of flowerless 
 plants; Mycology, the study of fungi; Agrostology, the stud}' of grasses. 
 
 Agricultural Botany. — This is subdivided into a number of different 
 departments, such as Agrostology, or Graminology, the study of grasses 
 and of their culture; Horticulture, the study of garden plants and of 
 their culture; Floriculture, Pomology, and Forestry. Doubtless a ver\' 
 large and important department will yet be established for the study 
 of the culture of medicinal plants. 
 
 Medical Botany. — This term is self-explanatory as to its general 
 nature. In use, however, it should be more strictly regarded than is 
 customary. The term originally included all botany relating to medi- 
 cinal plants; but with the development of Pharmacy the greater portion 
 of what was once comprised in the former term has naturally and per- 
 manently established itself in the form of the separate department, 
 Pharmaceutical Botany. Medical Botany properly concerns itself with 
 the medicinal properties and active principles of plants, and the deter- 
 
20 FUNDAMENTAL CONSIDERATIONS 
 
 mination of their uses, iiioluding the principles (l)ut not the practice) 
 of their preparation as based upon such facts, and their chissification in 
 view of medical considerations. 
 
 Pharmaceutical Botany. — In its widest scope, Pharmaceutical Botany 
 would include the classification, phytography, histology, distribution 
 and culture of medicinal plants, and the collection, preservation, 
 packing, transport, commerce, identification and selection, composition, 
 and methods and processes of preparation for use of the drugs derived 
 from them. From this it would follow that the pursuit of pharmaceu- 
 tical botany would demand a thorough knowledge of nearly all depart- 
 ments of scientific botany. This conclusion is to be modified, in view 
 of existing conditions, in important directions. The pursuit of the 
 study to such an extent would almost necessarily involve the a^'erage 
 pharmacist, at least in this country, in financial failure, through the 
 inattention to practical afl^airs which would ensue. It is the peculiar 
 office of the teacher of technical science to place its practical benefits 
 within the reach of his students, while relieving them from attention 
 to the greater portion of the field. It is not to be overlooked, however, 
 that while such a process of extensive exclusion is possible, utility 
 requires that a corresponding degree of elaboration shall be attained 
 in special directions. The faithful teacher, moreover, will not refrain 
 from urging as liberal an indulgence in extra-utilitarian study as indi- 
 vidual circumstances will properly permit. The directions in which 
 botanical knowledge is most useful to practising pharmacists will 
 determine the most important requirements for botanical study. 
 
 Pharmacognosy. — The identification, valuation, and selection of drugs 
 — that is to say. Pharmacognosy — constitute the principal field for the 
 exercise of botanical knowledge on the part of the pharmacist. 
 
 It is convenient to divide botanical pharmacognosy, like vegetable 
 anatomy, into gross and minute, the latter concerning itself with those 
 characters which require the compound microscope for their demon- 
 stration. 
 
 Subjects Essential to Pharmacognosy. — Remembering that vegetable 
 drugs may consist of the entire plant or of any one or more parts thereof, 
 and that they may reach the pharmacist in any condition, from that of 
 unbroken, or even fresh, to that of a fine powder, the departments of 
 botany necessarily pertaining to pharmacognosy and materia medica 
 will appear as follows: A knowledge of classification or systematic 
 botany, while a prime necessity in medical botany, there being a distinct 
 co-relation between natural classification and medicinal value, is one 
 
ORDER OF SUBJECTS 21 
 
 of tlu> less practical and essential elements of ])liannacentical botany. 
 Still, it aids the student in the ai)i)licati()n of i)hytography and espe- 
 cially in understandinfj; distribution, and it serves to crystallize and 
 systematize his knowledge of groups of medicinal agents. A good 
 working knowledge of phytography may be regarded as the leading 
 essential. If the drug is to be sought by the pharmacist in nature, he 
 can recognize it only through phytography, whether that knowledge be 
 acquired through folk-lore or book-lore. If, on the other hand, he seeks 
 the crude drug in commerce, he merely restricts his phytography to the 
 plant-part under inspection, and so far from being by this consideration 
 relieved from phytographical labor, its requirements are the more exact- 
 ing and its methods the more refined, as the recognition and estimation 
 of a fragmentary representative becomes more difficult than that of the 
 complete individual. As "Phytography" in its ordinary employment 
 is about equivalent to "the study of the manifest organs of plants," 
 or of their gross units of structure, morphology becomes the key to the 
 situation. 
 
 When drugs come to hand in a comminuted condition, the compound 
 microscope is the only resource, and the department of plant-histology 
 becomes the foundation of work. As will be shown farther on, the 
 greater portion of this subject can be passed over, but that portion 
 which receives attention, permitting the recognition of detached tissue- 
 elements and the determination by their examination of their source, 
 requires observations quite as careful and knowledge quite as accurate 
 as are called for in any other portion of the field. In the New York 
 College of Pharmacy, for the students of which this work is specially 
 prepared, the use of the compound microscope, and the subject of 
 histology, are separately taught, and the treatment of this important 
 subject is left to the appropriate department. 
 
 Finally, we note that only an insignificant portion of the materia 
 medica includes the bodies of flowerless plants, so that the great division 
 of Cryptogamic botany, as regards its detailed treatment, is not essential 
 to Pharmacognosy. 
 
 Order of Subjects. — In attempting a comparative view of the series 
 of plants, it is unquestionably well to begin with the lowest form and 
 follow the line, or rather lines, of ui)ward (kn-elo])ment; but in gaining 
 our first knowledge of the structure of the })lant organism, sound and 
 accepted rules of pedagogy require that we begin with the more obvious 
 characters of the higher plants, and pursue the analytic method, so far 
 as the special conditions of the case will ])erniit. 
 
22 FUNDAMENTAL CONSIDERATIONS 
 
 It has been repeatedly remarked that ])hint hfe is a circle of germina- 
 tion, growth, and reproduction, passing again into germination. It 
 therefore makes little difi'erence, on general principles, at which point 
 we enter upon our series of observations. Begin where we wull, we must 
 labor at the disadvantage of requiring more or less knowledge of facts 
 preceding our point of departure, and therefore not as yet possessed. 
 In special cases, however, there is much more room for choice, and 
 there are many reasons why we would advise pharmaceutical students 
 to commence b}- observing the organ concerned in reproduction, namely, 
 the flower. 
 
CHAPTER II 
 
 ANTHOLOGY: THE GENERAL NATURE OF THE FLOWER 
 
 The Phytomer. — In order to accurately understand the structure of 
 the flower, we must first consider the general characters of its struc- 
 tural units, which are the same as those of the stem upon which it 
 is borne and of which it is a part. These are well displayed in a 
 willow twig (Fig. 1), presenting a main stem, with perhaps short 
 branches below and leaves above. These leaves are found, upon exami- 
 nation, to arise at regularly occurring points, thus dividing the stem 
 into parts which are seen to possess definite and uniform characteristics. 
 In common language these parts are called "joints," and technically, 
 Phj'tomers or Phytons. 
 
 Units of Structure. — The upper portion of each phyton is commonly 
 somewhat enlarged and it possesses the power of giving rise to three new 
 structures: (1) the leaf (a), or in many plants a circle of two or more 
 leaves; (2) a superimposed phytomer, continuing the growth of the 
 stem in its original direction; (.3) a branch extending the growth of 
 the stem in a lateral direction, or, if there be more than one leaf, then 
 a corresponding number of such branches. Upon the upper portion of 
 the stem the branches are seen still undeveloped, and in the form of 
 buds (6). The bud originates, with rare exceptions, at the point where 
 the leaf emerges from the stem and upon its upper side. This point is 
 known as the Leaf-axil. The portion of the phytomer which gives 
 origin to these three structures is called its Node (c). The portion 
 intervening between two nodes is called the Internode (d). The inter- 
 node does not normally possess the power of giving origin to these 
 new parts. 
 
 The branch is found, after development, not to differ essentially 
 from the stem, so that a branch may be regarded as a lateral stem, 
 secondary, tertiary, and so on. In noting'hereafter the development of 
 the other parts of the plant out of those here named, we shall frequently 
 find the latter so modified that we shall be unable to recognize them 
 by the ordinary methods of examination, so that the relative positions 
 which they occupy will prove an important guide. A correct under- 
 
24 ANTHOLOGY: THE GENERAL NATURE OF THE FLOWER 
 
 standing of morpholo^n- requires, tiierefore, that we keep in mind the 
 following faets relating to the internode, no(k', U-af, branch, and super- 
 imposed phytomer. 
 
 1. Any of them may remain more or less undeveloped. 
 
 2. There is a definite and regular arrangement as to position of the 
 leaves upon the stem in most cases. 
 
 3. Several leaves and as many branches may develop from one node. 
 
 4. The branch normally develops as a bud in the leaf-axil, and con- 
 versely a leaf, in some form, is normally at the base of each branch in 
 its rudimentary condition. 
 
 Fig. 1. Leafy twig of 
 
 willow, its phytomers separated, a, leaf; b, axillary bud; c, node; d, internode. 
 
 5. All growth developing in the leaf-axil, with the exception of hairs 
 and similar appendages, is a manifestation of the branch. 
 
 6. All organs of the plant which w^e consider, except the root, the 
 hairs, etc., are constructed of the above parts in some modified form. 
 
 Certain necessary qualifications of the above statements can be made 
 only when we come to the study of the stem, and these do not involve 
 any failure to understand correctly the principles of anthology. 
 
 Propagation by Nodes. — Before proceeding to consider the forms of 
 structural modification of phytomers in the development from them of 
 
 fMOnRTY LIBRABff 
 
 J». C State C#«««« 
 
PROPAGATION BY NODES 
 
 25 
 
 the fl()\v(>r, certain iini)()rtiiiit i)r<)i)erties ])ertaiiiiii<i; to tlieiii, in addition 
 to their abihty to inultii)ly and grow as above indicated, shouhl receive 
 attention, in onh'r tliat hiter a comparison of reproductive methods can 
 l)e instituted. It is found that if, in the case of many plants, a stem 
 be laid prostrate in the soil, its connection with tlie parent not destroyed 
 (P'ig. 2), its nodes, in addition to jwoducing branches (a), may develop 
 roots (/;) similar in structure and function to those of the parent. If 
 now the phytomers be sei)arated through some portion of the internode, 
 they will heal the wound so produced by the formation of a callus (c), 
 continue to grow independently, and become plants similar to the parent. 
 Such a process, here of artificial production, is of frequent natural 
 occurrence and is called Propagation. It is seen to be, in this case, 
 purely vegetative, and may be defined as the production by vegetative 
 processes of a plant-body growing independently and separately from 
 that from which it was derived. 
 
 Fig. 2. Propagation by layering, a, axillary bud developed into a stem; b, adventitious roots; 
 
 c, callus. 
 
 Various other modes of stem-propagation may here be referred to, 
 and it may be remarked that the process is not confined to the node, 
 occurring in exceptional cases from fragments of the internode, root, 
 or even leaves. The phytomers, instead of remaining attached during 
 the rooting process (Layering), maybe first separated (Propagating by 
 Cuttings). The cutting, in this case called a Scion, may be inserted 
 (Grafting) or a bud may be so inserted (Budding) imder the bark of a 
 living stem, or it may be caused to take root in the soil. Propagation 
 by tul)ers or parts of them, as in the case of the potato, is identical. 
 It may be remarked, in passing, that in tlic seed itself nature resorts to 
 a similar method, for the contained embr\() consists of one or more 
 
26 ANTHOLOGY: THE GENERAL NATURE OF THE FLOWER 
 
 phytomers. This process is, however, sexual, and is called Repro- 
 duction. 
 
 Composition of the Stem. — Roughly stated, the stem may be said to 
 consist of three portions: (1) A framework consisting of strands of 
 conducting vessels (54, g), associated commonly with fibers; (2) among 
 and around the last a quantity of soft non-fibrous tissue; (3) a covering, 
 membranaceous when young and changing greatly with age. 
 
 Composition of the Leaf. — All these parts are extended into the leaf, 
 the first existing in a system of branching ribs or veins, the second as a 
 filling in the meshes of the former, and the third as a highly developed 
 skin-like covering, the epidermis. 
 
 Parts of the Leaf. — Morphologically considered, the typical leaf 
 (Fig. 3) consists of three parts which, like those of the stem, will be 
 considered in detail hereafter. The base (a) bears the Pulvinus or 
 organ of attachment to the stem, frequently 
 extended into an encircling sheath, and upon 
 either side a membranous expansion (h) called 
 the Stipule. The stem of the leaf (c) is called 
 the Petiole. The blade {d) is called the Lamina. 
 In some plants an additional organ, the Ligule, 
 develops as an appendage upon the face, being 
 a modification of the stipule (Fig. 465, A,h). 
 
 Modification of the Structural Units. — If we 
 could observe the phytomers of such a twig 
 during the process of formation in the bud 
 (Fig. 4) we should find them in a more and more 
 rudimentary condition towards its apex or center 
 until we reached an ultimate growing point («), 
 where development had not yet manifested itself. 
 Yet this point would possess the power, under 
 proper conditions, of continuing the process of 
 development and growth of phytomers. It therefore may be said 
 to represent a certain amount of vital energy or potential growth. 
 Now, our fundamental ideas of flower structure rest upon the fact that 
 this vital energy or potential growth may be diverted from the produc- 
 tion of phytomers and leaves such as we have been considering and 
 may produce in their stead other structures in which resemblance to 
 and variation from them are mingled in variable proportions. These 
 new structures we then call Modified Phytomers and Modified Leaves. 
 The student should dwell upon this point until the exact meaning of 
 
 Fig. 3. Leaf of willow, a, 
 pulvinus or foot; 6, stipules; 
 c, petiole; d, lamina. 4. Dia- 
 gram of longitudinal section 
 through bud. a, the growing 
 point. 
 
THE FLOWER CLUSTER IS A MODIFIED BRANCH 
 
 27 
 
 these terms becomes clear. When hereafter he encounters, as he very 
 frequently will, a reference to some organ being modified or transformed, 
 it must never be understood that it was first produced and then changed. 
 The exact meaning is that the change takes place in the direction or 
 exercise of the energy which is to ])roduce the modified structure. 
 
 Modification Produced by Injury. — Such a diversion of energy may be 
 caused by accident, as seen in the so-called "Willow-cone" (Fig. 5), 
 resulting from an injury inflicted by an insect in depositing its eggs in 
 
 P 
 
 8 
 
 10 
 
 Fig. 5. Willow twig with tip transformed into a gall-cone through insect agency. C. Willow twig 
 after fall of leaves. 7. The same with axillary buds enlarged, in spring. S. The same with axillary 
 buds developed into (a) female flower-bearing branches, c, scale (modified leaf) from one of the nodes 
 of "a." 9. Scale with its axillary bud developed into a flower, consisting of a pistil only, o, the stipe; 
 6, the ovary; c, the style; d, the stigmas. 10. Longutidinal section through willow pistil, a, placenta; 
 h, ovule. 
 
 the center of a bud. A portion of the structures, ha\ing been originated 
 before such injury, will reach a partial development, but further pro- 
 duction is checked and a distorted product results. 
 
 Bud-scales are Modified Leaves. — In the cases which we shall have 
 to consider the modification dates from an earlier stage and is natural 
 and physiological, instead of pathological, as in the case of the willow- 
 cone. Fig. 6 represents a twig after the fall of its leaves in the autumn. 
 Each bud is seen protected by its lowest leaf, permanently enlarged, 
 and developed into a covering scale. At the base is seen the scar of the 
 leaf in the axil of which the bud was developed. Fig. 7 illustrates the 
 twig in the spring after early growth has enlarged the buds. 
 
 The Flower Cluster is a Modified Branch. — In Fig. 8 (a) the covering 
 scale has fallen, the branch has developed to a length of an inch or so, 
 
28 ANTHOLOGY: THE GENERAL NATURE OF THE FLOWER 
 
 and its structure can be seen to consist of a great number of very short 
 phytomers, each of the crowded nodes bearincf a scale (c) and in its 
 axis (Fig. 9) a peculiarly shaped body (a, b, c, d). These bodies, as we 
 shall soon see, are flowers, and this entire bunch is a flower cluster. 
 That the scales are modified leaves is proved not only by their position, 
 as pre^•iousl^' explained, and to be further explained in our study of the 
 leaf, but by the fact that in exceptional cases the branch will produce 
 them in a form intermediate between that of a scale and of an ordinary 
 leaf (Fig. 13, a). 
 
 Each Flower of the Cluster is a Modified Branch. — Such being the case, 
 anything produced in their axils must, according to the same laws of 
 position, be modified branches. We must therefore regard the flower 
 shown in Fig. 9 in the axil of the leaf, as a modified branch, one of a 
 great many produced upon the parent modified branch shown in Fig. 8. 
 How profound is the modification which has taken place in the latter 
 can be appreciated from a consideration of its reduced size, for it is now 
 approximate!}^ full grown. The great number of phytomers upon it, 
 had they reached the form and extent of development reached by those 
 in Fig. 1, would have produced a branch many feet, or even yards, in 
 length, whereas in their present form they will produce a structure only 
 an inch or two long. As we shall soon see, increased complexity 
 of structure has replaced the greater amount of tissue-growth of 
 the leafy branch, a cluster of flowers having been produced in its 
 stead. 
 
 The Flower Explained and Defined. — Examining now the little modified 
 branch (Fig. 9) taken from the larger branch (Fig. 8, a), we observe 
 that it presents two uniform portions or halves, united into a single 
 body except at the tip, where they are separate. In exceptional cases 
 we find this separation extended downward, perhaps even to the base 
 of the body, and each of the separated portions expanded, formed and 
 veined very much like a small leaf, which, in fact, it is. The little branch, 
 a, b, c, d, is thus to be regarded as bearing two leaves which have been 
 developed in a united condition. Upon dissection (Fig. 10) the body 
 thus formed from these two leaves is found to be hollow at one portion, 
 containing two slight projections upon its inner wall (a), and upon these 
 a number of minute rounded bodies (6), If allowed to develop and 
 mature under the requisite conditions, we should find that these bodies 
 had become seeds. The structure ])roducing them we now see to be a 
 branch, so modified as to produce seeds, and this constitutes our definition 
 of the flower. 
 
THE PISTILLATE OR FEMALE FLOWER 
 
 29 
 
 Some Flowers are Imperfect. — It does not follow that because con- 
 structed for the production of seeds, a flower is always capable of per- 
 forming this office independently, and, indeed, such is not the case with 
 the flower under consideration, which is, therefore, an Imperfect ore. 
 
 Sex and Sexual Reproduction.- — INIinute microscopical examination 
 discloses within the bodies which are to become seeds, minute structures 
 called JNlacrospores, which, after germination and growth in that i)lace, 
 produce cells comparable, in their essential characters, to the ova of 
 animals, and requiring a similar fertilizing process to cause their develop- 
 ment.* Flowers, or at least certain of their products, are thus seen to 
 possess sex and to be capable of performing sexual reproduction, or 
 reproduction proper. Commonly, both sexual parts are present in one 
 flower, and of these the female, the 2-leaved branch here considered, 
 and in this case all that there is to the flower, is called the Gynaecium, 
 frequently represented by the symbol G. 
 
 Fig. 11. Willow twig with axillary buds developed into (a) male flower-bearing branches. 12. Scale 
 (modified leaf) from 11, a, with its axillary branch developed into a male flower consisting of two 
 stamens, a, position of node; b, scale; c, filament; it. anther. 13. .Abnormal willow twig, the scales 
 
 (o) of its flower-bearing branch intermediate between the ordinary form and the leaf. 
 
 The Gynaecium is Composed of One or More Pistils. — In Fig. 47, the 
 gynaecium consists of fl\c such bodies, and in other flowers it consists 
 of various numbers. One of them is called a Pistil, so the gyn;;ecium 
 may consist of but one, or of any number of pistils. 
 
 The Pistillate or Female Flower. — This flower (Ing. 9) possesses only 
 the gynaecium, and is therefore often s])()ken ( f as a "Female Flower," 
 technically a Pistillate flower, and indicated by the .-symbol •.. 
 
 * For an explanation of this subject see Chapter IX. 
 
30 ANTHOLOGY: THE GENERAL NATURE OF THE FLOWER 
 
 Fig. 14. Diagram representing 
 transverse section through anther, 
 o, theca, containing pollen; 6, con- 
 nective; c, locellus. 15, alder twig. 
 o, pistillate-flowered branches; b, 
 staminate-flowered branches. 
 
 The Staminate or Male Flower. — Before considering the structure of 
 the pistil we will examine a "JNIale Flower," borne, in the case of the 
 willow, upon a plant which produces no pistillate flowers. Fig. 11 
 illustrates branches (a) crowded with male 
 flowers each (Fig. 12, a), as before, in 
 the axil of a scal^ (6). In this case the 
 two modified leaves forming the flower are 
 entirely separate and the hollow portion of 
 each {d) is small, borne at the summit 
 of a stem (c) and filled (Fig. 14) with a 
 great number of minute rounded bodies. 
 These correspond, though of the other sex, 
 to the macrospores which we have found 
 the pistillate flower to produce, and they 
 are called IMicrospores — in flowering plants, 
 Pollen-grains, They possess the power of 
 germinating, growing, and producing Male 
 Cells, comparable to the spermatozoa of 
 animals, and requisite for the fertilization of the corresponding egg- 
 element produced by the macrospores. 
 
 The Androecium is Composed of one or more Stamens. — The male por- 
 tion of a flower is called the Androecium, frequently indicated by the 
 symbol A, and it consists of one or more Stamens, in this case of two. 
 As this flower consists only of androecium, it is known as a Staminate 
 Flower, indicated by the symbol d. 
 
 The Sporophyte, Sporophyll, and Sporangium. — We have now seen that 
 both the stamen and the pistil, homologues of leaves, exist for the 
 production of spores. A modified leaf producing spores is called a 
 Sporophyll. Both the stamen and the pistil form hollow bodies for 
 containing one or more spores. Such a spore-case is called a Sporangium 
 or Sporange. A plant producing sporophylls and sporanges is called a 
 Sporophyte. JMacrosporophytes, Macrosporophylls and Macrospor- 
 anges are those producing only macrospores or female spores. Micro- 
 sporophytes, Microsporophylls, and INIicrosporanges are those producing 
 only microspores or male spores. 
 
 Dioecious, Monoecious and Polygamous Flowers. — When, as in this 
 case, the macrospores are produced })y one plant and the microspores 
 by another, the plant is dioecious. If in addition each plant produced 
 some perfect flowers it would be Dioeciously Polygamous. If, as in the 
 Alder (Fig. 15) pistillate flowers (a) and staminate flowers (b), or other- 
 
PARTS OF THE PISTIL 31 
 
 wise stated, spores of both sexes, are produced by tlie same plant, it 
 is Monoecious. If, in adition, the phmt bear some perfect flowers it is 
 Monoeciously Polviianious. 
 
 Hermaphrodite and Perfect Flowers, — When, as illustrated in Fig. 17, 
 the flower possesses both gynaecium and androecium, it is Hermaphro- 
 dite, indicated by the symbol 9. Hermaphrodite flowers are not 
 always perfect, as one of the organs, while perfect in form, may be 
 functionless; whereas, in order to be perfect, both parts mnst be present 
 and functionally active. 
 
 Degrees of Imperfection. — Imperfect flowers present all intermediate 
 grades between that last mentioned and that in which there remains 
 no trace of the lost part, or in which it has even been transformed into 
 an organ of a different kind. 
 
 Parts of the Stamen. — The stem-like portion (Fig. 12, c) regarded as 
 corresponding to the petiole of the sporophyll, is the Filament. The por- 
 tion containing the spores or pollen is the Anther (d). The two halves of 
 the anther, each corresponding to a half of the lamina of the sporophyll, 
 are the Thecae (Fig. 14, a). At an earlier stage each theca is subdivided 
 into two Locelli (Fig. 14, c), and in many plants this condition persists 
 to maturity (Fig. 138). The portion connecting the thecae with one 
 another and with the filament is the Connective (b). Our detailed 
 study of the stamen, as of the pistil, may here be anticipated by the 
 statement that any or all of their parts may in different flowers be found 
 modified in an extreme degree by reduction, exaggeration, or special 
 form of growth, and may bear appendages in great variety, their true 
 nature, or even their identity, in many cases being thus masked. Often 
 an a])i)endage aj)parently consisting of a modified stipule exists. 
 
 Parts of the Pistil. — The stem-like base (Fig. 9, a), not present on 
 most pistils, is the Stipe or Thecaphore. It represents the united 
 petioles of the sporophylls. The body of the pistil represents either a 
 single sporophyll having its edges brought together and united, with 
 the upper leaf-surfaces inside of the cavity (Figs. 219 and 220), or, as 
 in this case, more than one sporophyll, the edges of one meeting those 
 of the other in the same manner (Fig. 27, e) or in many cases in a^ifl'er- 
 ent manner. The edges, after meeting along the hollow portion, project 
 inward more or less, while along the tip, for a greater or less distance, 
 they may be everted, as seen in Fig. 17, b. A s])oroi)hyll of a pistil is a 
 Carpel, and we see that a pistil may consist of one or more carpels. 
 
 The seed-rudiments which ])r()duce and contain the macrospores 
 are the 0^•ules (Fig. 10, b). The outgrowth from the inner wall of the 
 
32 ANTHOLOGY: THE GENERAL NATURE OF THE FLOWER 
 
 ovary iipon which the ovules develop is the Placenta (Fig. 10, a). The 
 hollow portion of the pistil, containing the placentae and ovules is the 
 Ovary (Fig. 9, b). The divisions of the ovarian cavity, which sometimes 
 exist, are called Cells (Fig. 221, etc.), and the partitions which separate 
 them are called Septa or Cell walls. A point upon a pistil (Fig. 9, d) 
 which lacks its epidermis and permits entrance into the ovary of the 
 pollen-product is a Stigma. (See also Figs. 191, etc.) A portion con- 
 necting the stigma to the ovary, narrower than the latter and usually 
 not hollow, is the Style (Fig. 9, c). 
 
 The leafy nature of the Carpel and its products is well illustrated 
 by Fig. 19, which represents a reverted state of the pistil. 
 
 The Essential Organs. — Since the androecium and gynaecium are 
 capable of producing seeds without the necessity for other floral parts 
 they are commonly known as the Essential organs, others as the Non- 
 essential organs. 
 
 Protection Needed by the Essential Organs. — The danger of accident, 
 as the result of blows, punctures, erosion, or even changes of tempera- 
 ture, to the complex mechanism and delicate structure of the essential 
 organs, and the resulting necessity for their protection, is obvious. In 
 the case under consideration the flowers are so closely crowded upon 
 their supporting branch that their leaf-scales (which are not parts of 
 the flowers, but grow out underneath them, from the nodes) afford 
 the necessary protection. But commonly this is not the case, and each 
 flower must provide and possess its own protecting organs. It must be 
 borne in mind, however, that protection is usually the least important 
 office which such organs fulfil. 
 
 The Calyx. — A series, or apparent or real circle, of such modified 
 leaves, underneath or surrounding the androecium, is displayed in the 
 flower of Pulsatilla (Fig. 16, a) and constitutes its Calyx, frequently 
 indicated by the symbol K, the several leaves being called either Sepals 
 or Calyx-Lobes, in accordance with conditions to be considered hereafter. 
 
 The Corolla. — Commonly, there is a second series or circle betAveen the 
 calyx and androecium, as in the buttercup (Fig. 17, a), and this is called 
 the Corolla, frequently indicated by the symbol C, its several leaves. 
 Petals or Corolla-lobes, according to their condition. Rare cases 
 occur in which, although but a single circle is present, it is regarded as 
 a corolla. 
 
 Sinuses. — The space between two adjacent petals or corolla-lobes — and 
 the same is true of a similar space between any two organs or divisions 
 standing side by side — is called the Sinus. 
 
THE TORUS 
 
 33 
 
 Petals and Sepals. — Occasionally the petals will he mimeroiis, forming 
 more than one circle. A petal or sepal is normally not composed of 
 distinct parts, unless it be by a narrowed insertion, called the Unguis 
 or Claw, which is frequently present (Fig. 18, a), the broad part being 
 called the Lamina, Blade, or Limb. It is then said to be r'nguicu- 
 late. Usually the form of sepals and petals is more obviously leaf-like 
 than that of the stames and carpels, and frequently in color and texture, 
 particularly of the sepals, they are strongly foliaceous. The calyx and 
 corolla may, however, possess any color or texture and they may be 
 similar or dissimilar, usually the latter, in this feature. The petals, as 
 w'vW as the sepals, may even difl'er among themselves in color and texture. 
 
 Fig. 16. Flower of PulsaliHa, subtended by epicalyx, with calyx of 6 sepals; a, torus; 6 and c, rudi- 
 mentary or aborted petals 17. Flower of Adonis, a, petal; &, pistil; c, stamen. 18. Unguiculate 
 petal of Diaiithus. a, unguis or claw. 19. Flower with its carpel partly reverted to the leaf-form. 
 
 The Perigone. — The calyx, or the calyx and corolla together when both 
 exist, constitute the Perigone, less aptly called the Perianth or Floyal 
 I'nvelopes. A flower possessing both calyx and corolla is called 
 Dichlamydeous; one with calyx only, Monochlamydeous, indicated 
 by Co, and one with neither, Achlamydeous or Naked, indicated by 
 Ko-Co. Those which have no corolla are called xA.petalous. 
 
 The Complete Flower. — A flower possessing calyx, corolla, androecium, 
 and gynacciiini is called Complete. 
 
 The Neutral Flower.— Some i)lants habitually i)roduce a portion of 
 their flowers without essential organs (Fig. 2(18, a). Such flowers are 
 called Neutral. 
 
 The Torus. — It must ever be borne in mind that all these parts are 
 constructed of the modified leaves of the floral branch. The latter is 
 called the Torus or Thalamus, or, less desirably, the Ileceptacle. The 
 torus may, therefore, be defined as the reduced branch which gives origin 
 to the jxirts of the /lower {a, in Figs. 10, 23, and 24). 
 3 
 
34 ANTHOLOGY: THE GENERAL NATURE OF THE FLOWER 
 
 Relation of the Flower and its Parts to the Branch and its Leaves. — The 
 relation of these parts to their branch may be displayed by comparing 
 the leafy stem of a lily Mith the dissection of a lily flower (Fig. 20). 
 
 Fig. 20. Diagram showing homology between leafy stem and flower of lily, the lowest whorl of former 
 corresponding to the calyx of latter, the second to the corolla, the third and fourth to the two sets 
 of stamens, the uppermost to the carpels, the torus to the branch. 
 
 The Epicalyx. — ^What appears to be a double calyx, or one calyx 
 outside of another, is frequently seen. This appearance is sometimes 
 
 Fig. 21. lAndoiCallirrhoe. a, epicalyx; 6, calyx; c, corolla. 22. The same expanded. 23. Apetalous 
 flower of Hepatica. a, torus; 6, calyx. 24. The same, calyx removed, o, the torus showing the epi- 
 calyx as distant. 
 
 due to the actual manifestation of two circles, as in the mustard; at 
 others to appendaging (see Fig. 36), but usually to a circle of modified 
 
THE EPICALYX 35 
 
 foliage leaves standing close to the torus (Figs. 21 and 22, a), and 
 known as the Epicalyx. When, as in this case, the flower has in addition 
 a calyx and corolla the real nature of the epicalyx is readily understood. 
 But when (Fig. 23) there is no corolla, the calyx (h) being colored like 
 one, the epicalyx may easily be mistaken for a calyx. In this instance, 
 however, it may be seen by turning back the epicalyx or removing the 
 calyx (Pig. 24) that the point of insertion of the former is upon the 
 stem below the torus («), so that it can be no i)art of the flower 
 proper. The divisions of the epicalyx are called Bracts, though the 
 term is not restricted to this use, as will be seen farther on. 
 
CHATTER III 
 
 LAWS OF FLORAL STRUCTURE 
 
 Meaning of the Term. — When we speak of a natural law as governing 
 a certain natural object, we refer merely to some observed mode or 
 manner of the existence of that object. Thus it is a law that water 
 flows downward, because that has been observed to be one of the 
 peculiarities of this substance. Similarly, warm air rises, wood burns 
 when fire is applied to it, and the sepals and petals of a flower possess 
 a similar form to that of the leaves of the plant on which they grow 
 and of which leaves they are homologues. Nevertheless, water will 
 sometimes run up hill because it is forced up, warm air sometimes does 
 not rise because it is confined, wood will not burn because it is wet or 
 otherwise fireproof, and the sepals and petals will not conform with the 
 leaves because some plants have no leaves, or because the influence of 
 some other law, known or unknown to us, has interfered with the action 
 of the one stated. 
 
 Under the natural and unobstructed influence of the morphological 
 development of the flower from a branch and of its parts from the leaves 
 of that branch, the flower and its parts would possess certain definite 
 and typical characters. In the process of such development, however, 
 there is a constant tendency toward variation from the typical state, 
 the extent and direction of which variation are determined by the 
 external conditions and forces to which the living plant is subject, so 
 that, as a rule, flowers differ greatly from that typical state. A careful 
 study of all flowers will nevertheless show that their general plan of 
 structure is in accordance with these laws, with more or less variation 
 in the details. 
 
 Modification of the Typical Flower. — We shall here consider the laws 
 of floral structm-e in relation to the following characters: The relative 
 number and position of parts of different kinds or of different series, as 
 those of the calyx compared with those of the corolla, or of the andro- 
 ecium compared with those of the gynaecium; the separation of each 
 part from every other, both of the same and of different kinds or series; 
 a similarity in form and size of the parts composing any one series; 
 
SYMMETRICAL FLOWERS 
 
 37 
 
 the characteristic form and function of all the parts of one kind. P'or 
 the identification of the parts of a typical flower, the few illustratiojis and 
 definitions already given will prove ample, but such flowers are very 
 rare. The great majority of them de\'iate from the tj'pe in one or more 
 directions to such a degree and in such a variety as to very frequently 
 create difficulty in identifying or circumscribing the several parts. To 
 fit the student for properly meeting the difficulties which so arise, as 
 well as for understanding botanical terminology, it is necessary to 
 specify and explain the principal forms of variation and to establish such 
 a classification of them as their varied nature will permit. 
 
 Law 1: Symmetrical Flowers. — The number of parts of each kind or 
 series is the same as of each other, or they have a common multiple. The 
 term Isomerous is used to indicate that the same number of parts enter 
 into the formation of the two or more circles to which the term is appHed. 
 In the case of the gynaecium, it is the carpels which are counted as 
 parts of the circle or series, whether developed each as a se])arate pistil, 
 or all united into one. The number of stamens is normally equal to 
 that of the sepals and petals com})inctl, that is, they form two circles. 
 If the flower is typical, the number of stamens will thus be just twice as 
 great as that of the parts of any other kind. A flower constructed in 
 accordance with this law is called Svmmetrical. 
 
 Fig. 25. Ai>i)ar('iitl.v nioiioniorou.s flowor of I/ippuris. a, raly.\; c, stamen; <i, pistil. 20. Longitu- 
 dinal section of same. 27. Dinierou.s flower of liicuntUa. a, sepals; b, original petals; 6', petal-like 
 bodies developed from one pair of stamens; c, the other pair of stamens, each divided into three; d, 
 pistil; e, eros.s-seetion of ovary, showing two placentae. 28. Trimcrous flower of VercUrutn. 29. 
 Tetramerous flower of Ocnulhcra. 30. Pentamerous flower of Grrauium. 
 
 Terms Indicafin;/ Niuncrical Synivicfri/.— Thus, the flower oi Ilipjniris 
 (Figs. 25 and 2G) has an entire calyx, apparently of one sepal, no corolla, 
 
38 LAWS OF FLORAL STRUCTURE 
 
 one stamen, and one carpel, and is, in its present state, Monomerous 
 or One-merous. The symmetrica] flower of Bicuculla (Fig. 27) possesses 
 two sepals (a), four petals (6 and b'), six stamens (c), and a two-carpelled 
 pistil {d and e), and is Dimerous or Two-merous. That of the Veratrnm 
 (Fig. 28) is similarly based on the plan of three, and is Trimerous or 
 Three-merous. Oenothera (Fig. 29) is Tetramerous or Four-merous, 
 and Geranium (Fig. 30) is Pentamerous or Five-merous. Fig. 43 displays 
 the plan of such a flower in cross-section and admirably illustrates our 
 second law also. 
 
 Suppression and Duplicatio7i. — Suppression results in the posses- 
 sion of less parts of one kind than are possessed by the typical flower, 
 while Duplication results in the possession of more. From what follows 
 it will be seen that neither suppression nor duplication necessarily inter- 
 feres with the numerical plan, although they frequently do so. 
 
 In the monochlamydeous flower of Pulsatilla (Fig. 16) suppression 
 of the entire circle of petals has occurred, although vestiges of them 
 remain. In the staminate and pistillate flowers of the willow, all 
 organs except a single series are suppressed. In the Claytonia (Fig. 45) 
 one complete stamen-circle has been suppressed. 
 
 In all these cases the remaining parts accord with the numerical plan 
 and the flowers are still symmetrical. Suppression which thus results 
 is called Regular Suppression. 
 
 Irregular Suppression. — This is displayed in the calyx of Claytonia, 
 with three of its five sepals wanting, in the androecium of the 4- or 
 5-merous flower of Horse-chestnut, which usually wants 1 to 3 of the 
 requisite number of stamens, and in the gynaecium of the 4-merous 
 flower of the olive (Figs. 31 and 32), which has but two carpels remaining. 
 In this flower, both forms of suppression appear to have occurred, for 
 but 2 of its 8 original stamens remain. To irregular suppression the 
 term Abortion has been applied, while by others this is restricted to 
 suppression in which a vestige of the lost organ remains, as in case of the 
 petals of Pidsatilla, and one set of stamens in Fig. 38, a. 
 
 Regular Duplication. — Duplication, like suppression, presents a 
 regular and an irregular form. Kegular duplication is seen in the 
 5-merous flower of the strawberry (Fig. 36), with its 10 sepals; the 
 3-merous flowers of Magnolia (Fig. 35), with 6 to 9 petals, and Meni- 
 spermum, with 12 to 24 stamens, and in the 5-merous flower of Maha, 
 which frequently has 10 carpels. 
 
 Chorisis and Syngenesis. — The development into two or more sepa- 
 rate parts of an organ originally entire is called Chorisis. This is exhibited 
 
SYMMETRICAL FLOWERS 
 
 3d 
 
 ^-AX 
 
 W 
 
 / / / 
 
 in the androecium of the mustard, where the multipHcation of two of 
 the stamens, each into two, has occurred. The development in a united 
 condition of two or more organs originally 
 separate is called Syngenesis. This is exhibited 
 in the two carpels of the mustard, which are 
 united to form a single pistil. 
 
 The nature of the process is illustrated by 
 the accompanying diagram (Fig. 30 A). Let 
 a represent a mass of elementary tissue which 
 is normally to develop into a stamen. If it 
 develop by a uniform growth throughout the 
 mass, it will become a single stamen, d. If, 
 upon the other hand, it grow separately at the points h, c, and d, it 
 must result in the production of three separate bodies, each of which 
 
 ^^ 
 
 Fig. 30 A. Diagram illustrating 
 
 the process of chorisis. 
 
 Figs. 31 and 32. Tetramerous flower of olive, 6 of its stamens and 2 of its carpels suppressed. 31. 
 Same in longitudinal section. 33. Androecium of mustard, showing a stamen developed as two, 
 through chorisis. 34. Flower of Tilia, showing each stamen developed into a cluster and a petal 
 through chorisis. 37 shows such a cluster detached. 35. Diagram of transverse section of Magnolia, 
 showing duplication through metamorphosis. 3G. Flower of strawberry, the calyx-appendages simu- 
 lating an cpicalyx. 38. Androecium of Fsorospermum, the stamens of one set undergoing chorisis, 
 those of the other aborted into gland-like bodies. 39. Flower of Stellaria, the corolla apparently 
 double. 40. A petal of the same, bi6d by chorisis. 41. Flower of rarojacHW, the calyx having under- 
 gone chorisis. 
 
 may become a perfect stamen, as represented by the dotted lines. The 
 process thus results in branching. 
 
40 LAWS OF FLORAL STRUCTURE 
 
 The important point for the student to note is that while we should 
 thus have three stamens as to form and function, we should have but 
 one as to the numerical plan of the flower, for all have developed from 
 the point belonging to one, and from the elementary tissues of one, and 
 all represent but one leaf-homologue. Sometimes the total number of 
 stamens (or other parts) will thus be multiplied, each element under- 
 going the same change, while at others only one or two in the circle will 
 be thus modified. The latter would result in irregular duplication. In 
 studying the law of position of parts, we must note the great difference 
 between duplication occurring in this way and that from the develop- 
 ment of a new circle independently of any process of chorisis. This 
 peculiarity of position in chorisis is well illustrated by the flower of 
 Tilia (Fig. 34), where three groups or fascicles of stamens can be seen, 
 each produced from one, and in that of Psorospermum (Fig. .38) where 
 there are five, the separation being here confined to the upper portion. 
 In this case, remains of a suppressed circle of stamens are present in the 
 form of gland-like bodies (a). Chorisis is well displayed in the calyx of 
 a floret of the Dandelion (Fig. 41), whose sepals have become divided 
 into numerous bristle-like portions, and in the corolla of the SteUaria 
 (Fig. 39), each of whose petals (Fig. 40) has become divided into two. 
 
 Production by Chorisis of a Part of a Different Kind. — Chorisis some- 
 times produces an organ of a difterent kind from the original, as in the 
 case of the original stamens of the Tilia, where each, besides dividing 
 into about 7 stamens, has at the same time yielded one or more little 
 petals (Fig. 37, a) standing in front of the stamen group. 
 
 Median and Lateral Chorisis. — Chorisis is Median in the case of the 
 last-mentioned petals, which stand in front of the organ out of which 
 they were formed. Lateral in the case of the stamens, which stand 
 beside the organ out of which they were formed. 
 
 An Indefinite Number of Parts. — When the number of organs of one 
 kind, as of petals, as in the rose (Fig. 59), or of stamens (Fig. GO), 
 exceeds twenty, it is commonly spoken of as Indefinite, indicated by 
 the symbol go , although in most cases it falls within certain definite 
 upper and lower limits which are of diagnostic value. 
 
 Indication of the Numerical Plan by Diagram. — The numerical plan 
 and deviations therefrom are often indicated pictorially by diagrams 
 like that shown in Fig. 43. When dots are introduced, as in this dia- 
 gram, they indicate the position of organs which should be present in 
 accordance with the floral type, but which have in that case suffered 
 suppression. A diagram thus marked is called Theoretical, while if 
 
ALTERNATION OF POSITION 
 
 41 
 
 the (lots arc omitted it is called Empirical. Frequently, also, a dot is 
 placed above the dia<,n-am to indicate the jiosition of the plant-stem on 
 which the flower is borne, this being the Su])erior or Posterior side of 
 the flower, while underneath it is often indicated the leaf or })ract in the 
 axil of which it is situated, this being the Inferior or Anterior side of the 
 flower, 
 
 ^S o 
 
 Fig. 43. Diagram of transverse section of Geranium, showing the alternation of parts. 44. Vertical 
 view of Illipe, one set of stamens alternating with, the other opposite to, the corolla-lobes, and several 
 of the stamens aborted. 45. Flower of Ctaytonia with outer set of stamens suppressed. 46. One of 
 the remaining stamens anteposod to petal. 47. Typical flower of Sedum. 48. Slightly irregular 
 coToWa. of Pelargonium. 
 
 Iiultvditon (if ilic Xiinicricdl Plan hi/ For/// ///a.- -The inanner of 
 indicating by formulae the numl)er of parts in calyx, corolla, androecium, 
 or gynaecium has already been indicated. It will now be seen that by 
 a combination of these expressions, the entire plan of the flower can 
 be indicated by a single formula. K3, C3, A3 + 3, G- indicates 3 sepals, 
 3 petals, 2 circles of 3 stamens each, and 2 carpels. K3, C3, A^ + 0, G^, 
 would indicate that the second circle of stamens had suffered suppres- 
 sion, but each of the first circle had divided into three. In a diagram, 
 the positions of the suppres.sed stamens would be indicated ^ ^-^ 
 bv dots, while the doubled set remaining would be indicated in /. . o 
 pairs, thus: The letter n, in j)lacc of a figure, as in the follow- 
 ing formula, Ko, Go Ao + n, G'', indicates that the number of parts of 
 that kind (in this case the stamens of the second circle) is not constant. 
 
 Law 2 : Alternation of Position. The parts of each circle alternate in 
 position with those of the adjacent circles. In other words, each i)art of 
 
42 
 
 LAWS OF FLORAL STRUCTURE 
 
 the flower stands opposite a sinus of the adjacent outer and inner circles. 
 Thus, in Fig. 44, the stamens of the circle nearest the corolla-lobes 
 alternate with the latter, while those of the next circle alternate with 
 the former and are consequently opposite to the corolla-lobes. In Fig. 
 43 the same relation can be observed between the other circles. It is 
 thus clear that the parts of two alternating circles, as of the first and 
 third, or the second and fourth, must stand opposite each other, or in 
 the same radial line. 
 
 Anteposition Resulting from Suppressioji. — It is also clear that if 
 two circles shall be brought into juxtaposition by the suppression of 
 an intervening circle, their parts will naturally stand opposed and thus 
 appear to invalidate our second law, as in the case of the stamens and 
 
 "Vi>^. 
 
 J7 
 
 Figs. 49 to 53. Figures illustrating torsion. 
 
 petals of Claytonia (Figs. 45 and 40), where the stamen-circle originally 
 standing between the other one and the corolla has been suppressed. 
 Organs thus placed, the one directly in front of the other, are called 
 anteposed. 
 
 Note should also be taken of the fact, already pointed out, that the 
 cluster of organs produced by chorisis corresponds in position with the 
 single part by the modification of which it was produced. 
 
 Position Sometimes Obscured. — In examining the position of parts 
 great care should be taken by the student to see the actual point of 
 insertion, as the free portion of an organ frequently deviates from the 
 line of its true position and leads to error. 
 
 Torsion. — One such condition which can easily lead to error is 
 Torsion, or twisting. This relates to a permanent condition of the 
 
REGULARITY 43 
 
 mature organ and not a temporary eml)ryonic state such as the twisting 
 of the coroUa in the bud. Torsion of the base of the coroHa is shown in 
 Fig. 49, of the stamens in Fig. 50, of the anther in Fig. 51, of the style 
 in Fig. 52, and of the fruit in Fig. 53. Torsion also frequently affects 
 other parts of the plant, especially the stems of flOwer and leaf. 
 
 The treatment of the subject of position here presented is necessarily 
 superficial and incomplete, owing to our failure to have considered 
 already the subject of leaf-arrangement. There is a direct correlation 
 between the arrangement of foliage-leaves and the parts of the flower. 
 As the arrangement of the former is sometimes by circles or whorls and 
 sometimes by spirals, it follows that some flowers may be arranged on 
 the former plan (Fig. 20), some (at least in part) upon the latter, and 
 such we actually find to be the case. There is no one of the floral series 
 but what at times exhibits in its parts (in most cases when they are 
 numerous) a well-marked spiral arrangement. Such are denominated 
 Acyclic, while those having their parts in true whorls or circles are 
 called Cyclic. 
 
 Flowers Normally Possessing hut One Stamen-circle. — It should be 
 noted that the very frequent occurrence of flowers possessing but one 
 stamen-circle, and this alternating with both carpels and petals, has 
 led to the belief that in some plants but one stamen-circle is the rule, a 
 second calyx-circle existing instead of the second stamen-circle. Care 
 should be taken not to confuse the idea of this second calyx-circle with 
 that of the totally different epicalyx. 
 
 Law 3: Regularity. — The parts composing one circle agree in form and 
 size. A How'cr all of whose circles obey this law is liouular. An illus- 
 tration is found in the flower of Veratnun (Fig. 28). 
 
 Ir regular it y and How it May Result. — Irregularity may result from 
 abortion (Fig. 44), where three of the upper circle of stamens are 
 different from the other five; from appendaging (Fig. 05), where one of 
 the five petals bears a long spur; or from mere variation in form (Fig. 
 110) or size (Fig. 48). Sometimes, as in the last case, the variation is 
 so slight that the student will be in doubt as to its existence, while at 
 other times an accidental variation in an individual plant may suggest 
 irregularity where it is not a characteristic. Very often an irregularity 
 so slight as to be scarcely perceptible in the open flower may be more 
 conspicuous in the bud. In cases of doubt the relationship of the plant 
 to others whose flowers are regular or irregular may aid to a decision. 
 
 A tendency to antero-posterior irregularity in flowers would apjiear 
 to be generally characteristic of their higher development. 
 
44 LAWS OF FLORAL STRUCTURE 
 
 Law 4. — Each part of a circle develops separate and disconnected from 
 all others in that and in other circles. As the mass of tissue forming 
 each of the floral parts becomes isolated and projected from the torus, 
 its margins and faces should develop completely separate from those 
 of all adjacent parts. The law assumes that growth shall continue in 
 the isolated portions, by which process they must continue separate. 
 But this form of growth of the parts does not always occur. Very 
 commonly the point of growth changes or becomes restricted to the 
 basal portion, where they have not yet separated from one another. 
 This projection from the torus of an undivided or unseparated portion, 
 and its subsequent growth, must clearly result in the development of 
 a portion of the flower consisting of more than one floral part in union. 
 The component parts are usually indicated by more or less of a separa- 
 tion of their apical portions. This principle has been already carefully 
 explained in connection with Fig. 42. 
 
 Connaiion. — There is no other direction in which deviation from the 
 type represented in Fig. 47 is so frequent and variable as in that just 
 described, nor in which the results are so far-reaching or call for so 
 extensive a classification and terminology. The deviations are of two 
 classes. When a part is united laterally with another part of the same 
 circle the condition is called Connation, Cohesion, Coalescence, or 
 Syngenesis. When connation does not exist the parts are said to be 
 Distinct or Eleutherous. Connation will be discussed in our detailed 
 consideration of the several floral parts. 
 
 Adnation or Adhesion. — In the second form, called Adnation or Ad- 
 hesion, one circle is more or less united with another. Adhesion may 
 affect any two or more circles of the flower, and it may affect an entire 
 circle or only one or more of its parts. Thus, Fig. 54 illustrates a 
 petal of the ^'anilla adnate to the ganaecium, while the other petals 
 are free. It is plain that when the calyx and gynaecium are adnate, all 
 the intervening circles must be included in the condition, as in the 
 lower portion of the colocynth (Fig. 5(5). Since all the parts start 
 from the torus at a, they must be adnate to the whole surface of the 
 ovary between the points a and /;. 
 
 Epigyny. — In the last case, as in all cases where one or more circles 
 are adnate to the gynaecium, the free or ununited ends of the parts 
 must lose the appearance of emanating from the torus and must appear 
 to emanate from the gynaecium. They are, therfore, said to be Epigy- 
 nous. At this ])oint the student should not fail to impress himself 
 with an understanding of the fact that in all such cases the epigynous 
 
THE IIYPANTIIIUM 
 
 45 
 
 organs really orifjinate at the torus, and that in a cross-seetion through 
 the adherent ])()rti()ns the niieroseope will often demonstrate the tissues 
 of such a part adnate to those of the part from which it appears to 
 emanate. In descriptive i)hrase()logy, the term "Calyx adherent" 
 always means "adherent to the ovary," or ejjigynons, e\en though the 
 
 Fig. 5-1. Adnate petal of Viuiilhi. Tm. (iynaiiilnius slauieiis i.f .\,l,iihim, as prevalent in the Apo- 
 cynaceae. 56. Flower of rolorjnth, with inferior ovary and superior (adherent) calyx. 57. Longi- 
 tudinal section through flower of I'Mox, .showing stamens adherent to corolla. 58. The same through 
 flower of cherry, showing adhesion of all parts except the pistil. 50. "Double" flower of rose, showing 
 the stamens of tlio ".single" fiower (60) transformed into ix'lals. 
 
 words "to the ovary" are omitted 
 condition is to say "Ovary inferior 
 
 Another mode of stating tl;e same 
 r " ( 'alyx su])erior." It frc(iuentl\- 
 happens that the condition is only partial, when the terms "Half 
 inferior" and "Partly inferior" are emi)loyed. 'riure are cases where 
 proper aj)])lication of any of these tei-nis is doiihtful and some ])fr))h'xity 
 is created. 
 
 The Ili/ixnilliliini.- In many cases tlie toiMis, wliicli is to he remem- 
 bered as the end of a hraiich, is hollow and has the lower portion of the 
 flower inside of it and adherent to the inner surface of its cup (Figs. 
 
46 LAWS OF FLORAL STRUCTURE 
 
 59 and 60). In this case the outer surface of its cup may be mistaken 
 for that of an adherent calyx. The enclosed portion of the calyx really 
 is adherent, but it is not visible, since it is enclosed and concealed by the 
 hollow torus, which is known as a Hypanthium. It is often extremely 
 difficult to distinguish between a simple adherent calyx and a hypan- 
 thium, and good botanists frequently disagree in particular cases. 
 
 Perigyny. — The insertion of a corolla or an androecium which is 
 adherent to a free calyx, as in the cherry (Fig. 58), or of an androecium 
 adherent to a free corolla, as in the Phlox (Fig. 57), is denominated 
 Perigynous. 
 
 Hyvogyny. — Organs which are not in any way adherent are denom- 
 inated Free, and because their insertion is manifestly upon the torus 
 underneath the gynaecium, they are said to be Hypogynous (Fig. 47). 
 
 Gynandry. — With the stamens adnate to the pistil the flower is said 
 to be Gynandrous (Fig. 54). The body thus formed of the united 
 androecium and gynaecium is technically known as the Column. (See 
 also "Stamen^column.") A peculiar form of gynandry is common 
 among the relatives of the Apocytmm (Fig. 55). 
 
 Law 5. — Each part preserves its own function and a characteristic form. 
 The forms freeing with this law correspond in general with those 
 which have been indicated in our account of the flower. Deviations 
 from it are caused by INIetamorphosis, Enation, resulting in the true 
 appendaging of an organ, the very similar process of exaggeration in 
 the growth of a part, retardation in its growth, or its suppression or 
 abortion. With the exception of the first, the results of these processes 
 will be discussed under the details of the respective parts. 
 
 Metamorphosis is the simulation in form or function, or both, of one 
 organ by another. The rose, which normally has but five petals (Fig. 
 60), is seen under cultivation to consist of a dense mass of them, in 
 many circles, becoming a so-called "double" flower. An examination 
 of the inner petals of such a flower (Fig. 59) discloses that they are 
 successively smaller and more stamen-like as they stand nearer the 
 stamens, indicating their origin through the metamorphosis of the 
 latter, which are fewer in proportion as the petals are more numerous. 
 In another form of the rose, the " Green Rose," the petals in turn appear 
 transformed into leaves or leaf-like bodies. Such accidental or artificial 
 deviations from the normal type are called Monstrosities. The sepals 
 also frequently present a leafy appearance, sometimes as an abnormality 
 but in most species habitually. Even the stamens and carpels fre- 
 quently display the latter abnormality. 
 
GLANDS 
 
 47 
 
 Retrograde Metam or pilosis. — In all of these cases the change is from 
 a more com])lex organ, or one of higher rank, to one of a lower, and is 
 called Retrograde i\retani()r])hosis, or Reversion of Type. 
 
 Progressive Metaiitorphosis also occnrs. It is seen in the gradual 
 transformation of bracts, themselves transformed leaves, into sepals 
 in the Barberry (Fig. (il), and of sepals into petals and petals into 
 stamens. Even stamens may become metamorphosed into carpels 
 or carpels into stamens, one instance being the flowers of the willow, 
 where organs have been seen intermediate in ai)pearance between the 
 two. 
 
 62. 
 
 Fig. 61. Structures from flower of licrhrris, interiiiodiate between petal and stamen. 62. Same 
 from flower of Castalia. 
 
 Teratology. — Cases of abnormal retrograde metamorphosis are very 
 common, and have given rise to a separate department of study known as 
 Teratology. 
 
 Enation or Outgrowth. — Enation and the effects ])rodnced by it are well 
 illustrated in one of their forms by the petals of certain genera of the 
 Ranunculaceae. The retention of a drop of nectar at the base of the 
 petal of some species of buttercup is effected by the presence there of a 
 minute scale (Fig. 03), covering over a slight depression. The nectar 
 is partly lodged in this pit, partly held between the petal and the 
 scale. In the Coptis (Fig. 04), a closely related plant, the dej)ression 
 is deepened into a more obvious cavity and the .scale is dispensed with, 
 while in the Delphinium. (Fig. 65) the cavity becomes a long tube. 
 
 Glands. — Although the detailed consideration of appendages will 
 be taken up in connection with tlie several organs to which they apper- 
 
48 
 
 LAWS OF FLORAL STRUCTURE 
 
 tain, we shall here consider a special class of them, called Glands, not 
 only of great importance in diagnosis and classification, but of such 
 physiological importance that from that jxnnt of \\e\v they constitute 
 a distinct organ of the flower. For the peculiarities of structure and 
 secretory function of glandular tissue, works on histology must be 
 consulted. Here we note that although glands are sometimes distributed 
 through the other tissues in such a way as to be imperceptible on 
 superficial examination, their tissue is at other times collected into more 
 or less conspicuous bodies of definite form and position. The term 
 "Gland" is frequently applied also to 
 bodies which resemble glands in location 
 and form, but which do not appear to be 
 glandular in function. Glands may be 
 stalked (Fig. 66, a), sessile (Fig. 67, a), 
 or depressed (Fig. 6S, a, see Nectary), 
 and they may develop upon various parts 
 
 Fig. 63. (a) frontal; (b) lateral, views 
 of base of petal of buttercup, showing a 
 scale which retain nectar in nectary. 
 64. Petal of Coptis, hollowed to form a 
 nectary. 65. Long hollow spur forming 
 nectary in flower of Delphinium. 
 
 Fig. 66. Stalked glands (a) on calyx of Dinemandra. 
 67. Sessile glands (o). 68. (a) Depressed glands (nectary) 
 on petal of Frasera. 69. (a) Basal gland prevalent in 
 the Apocynaceae. 70. (a) Glands at base of stamen of 
 Sassafras. 
 
 of the flower or plant. Those upon the outside of the calyx are exten- 
 sively utilized in classification in the family Mali)ighiaceae, Avhile those 
 upon the inside are so used in the families Apocynaceae (Fig. 09, o) and 
 Gesneriaceae. 
 
 Fig. 6S is an illustration of glands located upon the corolla, while 
 Fig. 70, a, illustrates them connected with the stamens, as seen in 
 Sassafras. 
 
 Glands upon filament-like stalks, suitably located, may easily be 
 mistaken for stamens, (ilands may be themselves appendaged. 
 
 As to their origin, it may be stated that glands frequently result 
 
EXAGGERATION OF GROWTH 49 
 
 from metamorpliosis of the remains of an aborted orj?an. Thus, in the 
 staminate willow-flower (Fig. 12) a small gland between the bases of 
 the stamens is supposed to represent the aborted pistil, while similar 
 ones at the base of the pistil, in the pistillate flower (Fig. 9), are supposed 
 to represent the aborted stamens. 
 
 The misleading effects of su])pression have been observed in Ilcpatica 
 (Figs. 23 and 24) in the absence of the corolla, the metamorphosis of 
 the calyx toward corolla and of the epicalyx toward calyx. Those of 
 abortion are seen in the Pulsatilla (Fig. 16), where the petals b and c 
 are reduced to simulate filaments. 
 
 Exaggeration of Growth is well displayed in the torus of the straw- 
 berry and the placentae of the watermelon (Fig. 312), which respec- 
 tively contribute the massive edible portions of those fruits. 
 
 The principles of anthology as api)Iied to the higher types of plants, 
 having thus been followed into and through the typical flower, and the 
 general nature of the deviations therefrom having been outlined, we 
 shall proceed to a detailed consideration of the several parts of the 
 flower, with the object of preparing us to interj)ret the multiform 
 appearances which those organs present in the extensive flora from 
 which our drugs are deri^'ed. 
 
 That division will not, however, close our consideration of flower 
 structure, as some imi)ortant modifications will remain to be discussed 
 in our chai)ter on pollination and fertilization. 
 
CHAPTER IV 
 
 THE PERIGONE 
 
 Study of the Perigone.— The perigone is to be studied as to the number 
 of its circles, their color, texture, and surface, the number of parts 
 forming each, their adhesion or cohesion, if existing, the form and 
 divisions, if any, of each and of its parts, appendages, secretions, meta- 
 morphosis or other variations, arrangement of the parts in the bud, 
 movements or other noteworthy habits, and duration. 
 
 Number of Parts. — The normal condition of two circles, the modifica- 
 tion of these through abortion, suppression, duplication and meta- 
 morphosis, and their agreement with the numerical plan of the flower 
 and its modification through the same influences, need no further 
 discussion. The number of parts entering into either perigone circle, 
 whether these exist in a distinct or coherent state, is indicated by the 
 appropriate numeral preceding the suffix "phyllous;" thus Monophyl- 
 lous, Diphyllous, Triphyllous, and so on. 
 
 Color and Texture. — The typical idea of a calyx more or less herba- 
 ceous and a corolla thin, delicate, and brightly colored, is not always 
 realized. In the Crocus and most related flowers the parts of both 
 circles are similarly petaloid. The petals of Garcinia are thick and 
 fleshy, in Caopia they are leathery, and in Alzatea hard and almost 
 woody, at least when dry. The surfaces of the sepals, particularly the 
 outer, are not commonly glabrous, while those of the petals are; but 
 even the latter are often glandular, pubescent, densely woolly, or even 
 prickly. No shade of color is denied to either circle of the perigone, 
 nor is the color necessarily uniform among its parts or even over the 
 surface of any one part. The shade and marldngs are very liable to 
 vary in different individuals of the same species, so that color is not 
 always a good character on which to base a determination. In general, 
 the color deepens as the altitude of the habitat increases. 
 
 Form of Parts. — The strictly typical state calls for a general resem- 
 blance between the form of the perigone parts and that of the foliage 
 leaves of the plant which bears them. They sometimes display a keel 
 corresponding to the mid-rib of the leaf, and as in the leaf, this may 
 
ADHESION 
 
 51 
 
 be continued into a terminal ])oint. They may be concave, as in Thco- 
 hroma (Fig. 71); the margin may be toothed and the a})ex tootlied or 
 fim])riated, as in Siletic (Fig. 72); the toothing of the margin may extend 
 into a ])imiatifid condition, as in the calyx 
 lobe of Rosa canina (Fig. 73), and that of 
 a toothed or fimbriate apex into the cleft 
 or divided state of chorisis. 
 
 The Pappus. — The peculiarly di\ided 
 calyx illustrated in Fig. 79, a, is denomi- 
 nated a rai)pus, and this term has been 
 extended to all forms of the calyx (Figs. 
 74 to S3) existing in that family (the 
 Com positae) and in some others. Fig. 80 
 illustrates the action of median, as well as 
 of lateral chorisis, in the development of 
 a double pappus, the outer circle being 
 much shorter and different in kind. 
 
 The se^•eral forms of perigone i)arts 
 corresj)onding to those of leaves (see leaf-forms) and numerous inter- 
 mediate ones not illustrated, should be carefully considered by the 
 student, as they ha^e a most important bearing ui)on the forms of the 
 corolla produced by cohesion, which we shall shortly consider. 
 
 FiK. 71. ConoMVc petiil of Tlicohronut. 
 72. FlowtT of .SiVi/K, the i)etals loothod 
 at apex and bearing a crown at junction 
 of limb with claw; also a conspicuous 
 anthophore in base of calyx. 73. Pinna- 
 tifid sepal of Jiusa. 
 
 IS. 76. n. 
 
 Figures illustrating forms of the pappus; Fig. 71. Pappus little changed from ordinary superior 
 calyx-limb. 75. That of Tanareium, reduced to a short cup. 70. That of Absinlhiuiri, practically 
 obsolete. 77. That of yVycthia, 2 of the calyx-teeth awned. 78. That of Griiidelia, the two remaining 
 calyx-teeth aristiform. 79. That of Aruica, the ordinary setose form. SO. The double pappus of 
 £ri(/(To;i, the outer series very short. 81. Plumose bristle from pappus of Lasiopoffon. 82. Scaly bristle 
 from pappus of Eriosphaern. H',i. Serrate bristle from pappus of Cineraria. 
 
 Adhesion. — Both adhesion and cohesion are exceedingly common in 
 the case of the })erigoiic. The foiiner has already been pretty fully 
 considered. \Vry rarely is it so coiniilete that there is not at least a 
 ])()rtioii of the parts remaining free. Since the adherent ])arts are 
 
52 
 
 THE PERIGONE 
 
 alternating, adhesion necessarily involves the ultimate effect of cohesion. 
 In the case of cohesion extended very high, peculiar effects, often 
 puzzling to the beginner, are produced, as in the case of Oenothera 
 (Fig. 29). 
 
 Here the calyx, after adhering to the entire surface of the ovary (e), 
 is continued upward in the form of a long, slender tube resembling a 
 flower-stem. Inside of this tube the petals and stamens are adnate, 
 and do not become free until they reach its summit. 
 
 Cohesion. — Cohesion, like adhesion, may be partial or complete. In 
 its slightest forms, with a mere band of union at the base, it may 
 escape observation, as in the case of the corolla of Lysimachia (Fig. 84). 
 In such cases a decision is best reached by carefully pulling away the 
 
 Fig. 84. Adnate corolla and androecium of Lysimachia, the parts of each coherent at the base only- 
 87. Completely separating calyptra of Eucalyptus. 88. Partly attached calyptra of Mitranthes. 
 89. Corolla of Oenothera escaping through a fissure in side of calyx. 90. Corolla of Ayenia, its petals 
 coherent at summit only. 91. Completely coherent petals of Ipomoea, leaving the margin merely 
 sinuate. 
 
 corolla. If there is a union, however slight, the corolla may thus be 
 removed as one body. Agglutination will occasionally cause an appear- 
 ance of cohesion, but upon applying the test here specified, the parts 
 will be found to separate readily, without the tearing of any tissue. 
 
 The Calyptra. — A peculiar and extreme form of cohesion is that in 
 which the sepals refuse to separate even at the apex wdien the flower 
 expands, and the calyx is torn loose from its basal attachment, falling 
 entire as a Calyptra, as in the corolla of Eucalyptus (Fig. 87), or remain- 
 ing attached at one side as in Mitranthes (Fig. 88). A modification of 
 it permits the remainder of the flower to escape through a rent in the 
 side, as sometimes in the case of Oenothera (Fig. 89). Very rarel}^ 
 cohesion exists at the apex only, a remarkable instance being the corolla 
 of Ayenia (Fig. 90). 
 
SPECIAL FORMS OF CALYX AND COROLLA 53 
 
 Terms Indicating Cohesion or its Absence.- — When tlic ])ctals are dis- 
 tinct the coroUa is said to he l^lenther()i)etaloiis or Choripetalous. The 
 ol(K'r hut less desirable term is Polypetalous. When they are coherent, 
 the corolla is said to be Gamopetalons or Synpetalous, the older and 
 less desirable term being Monopetalons. Corresponding terms lor the 
 calyx are Eleiitherosepalous, Chorisepalous, or Polysepalous, and 
 Gamosepalous, Synsepalous, or Monosepalous. In the gamopetalous 
 and gamosepalous state the parts cease to be designated petals and 
 sepals, and are known respectively as Corolla-lobes and Calyx- 
 lobes. 
 
 The relative altitude to which the cohesion is carried is indicated 
 by special terms. When existing at the base only, the circle is said to 
 be parted (Fig. 84) ; when extending about half-way up, as in Solainim, 
 Cleft (Fig. 92) ; when still farther, but yet leaving a considerable portion 
 ununited, as in Spigelia, Lobed (Pig. 97), and when having only traces 
 of the parts ununited, Toothed (Fig. 102). A peculiar form is that in 
 which the position of the parts is indicated by a mere waving irregular- 
 ity of the margin, as in the flower of Lpomoea (Fig. 91), which is then 
 said to be Sinuate or I 'ndulate. The student must not fail to discrim- 
 inate between the entirely different senses in which these terms are 
 here used, in reference to the entire calyx and corolla, and as used 
 previously in reference to the margin of a single part thereof. 
 
 Special Forms of Caljrx and Corolla. — We must next consider certain 
 specific forms of the calyx and corolla as wholes, which are of \ery 
 great diagnostic value. That the form of a gamopetalous corolla is 
 determined by the form of the ])etals of which it is composed is readily 
 seen by comparing Figs. IS and 98. In Fig. 18 we have a j)etal with 
 a long, slender claw and a broad limi). Several such petals united by 
 their edges must yield a corolla with a broad border supported upon a 
 long tube; just sucli a form is that represented by Fig. 98. Similar 
 results are shown in Figs. 97 and 99, and it is not difficult, on examining 
 these figures, to imagine the exact form of the component parts. In 
 Fig. 9;^ we have a union of somewhat broader petals, while those of Fig. 
 MY.] were so ^■ery sliort and broad as to have resulted in a saucer-slia])ed 
 corolla. 
 
 Although such characteristic forms are most numerous among the 
 coherent class, tiiey are not wanting among those in which cohesion 
 does not exist. Sometimes a non-coherent corolla will necessarily 
 assume such a form through the restraint exercisetl by coherent sepals. 
 At other times the form is entirely independent of such restraint. 
 
54 THE PERIGONE 
 
 The Tube, Throat, and Limb. — In such corollas and calyces as are 
 represented by Figs. 97 to 99, the narrow portion is denominated the 
 Tube and the broad portion the Limb. When the change from tube to 
 limb is not abrupt, there will be an intermediate portion, as displayed 
 at h in Fig. 94, called the Throat. Less frequently this term is ap])licd 
 also to the delimiting circle between the limb and the tube when these 
 do meet abruptly. Occasionally distinct contraction instead of a dila- 
 tation will be found at the throat, as very frequently occurs in other 
 parts of the tube (Fig. 100). 
 
 The Margin. — The terminal boundary line, including all its extensions 
 and intrusions, is called the Margin, The margin may intrude partly 
 or quite to the tube, so that the cohesion may include none or the whole, 
 or any part of the throat, or of the limb. 
 
 Special Terms Indicating Form. — The terms regular and irregular 
 apply to lobes precisely as though they were distinct sepals or petals 
 and to the united portions as well as to the lobes. Some of the terms 
 applicable to the forms of the gamopetalous corolla (and, of course, to 
 the gamosepalous calyx) refer to its entire body, while others refer to 
 its several parts. The former class, and among them those which are 
 regular, will be first considered. 
 
 The term Cylindrical is self-explanatory. If nearly cylindrical, it is 
 called Cylindraceous. Such shapes are shown in Figs. 29 and 99. If 
 such a one is manifestly angled, as in the calyx of MimiiJus (Fig. 94), 
 it is Prismatic, and the same is true of other tubular forms. If the 
 entire body flares regularly (Fig. 97), or if there is such a flaring portion 
 upon a cylindrical tube, it is called Infundibular or Funnel-shaped. 
 The less broadened infundibular forms are called Trumpet-shaped, as 
 in the honeysuckle. If the flaring portion or limb is flat, or nearly so 
 upon a cylindrical or cylindraceous tube, it is called Ilypocraterimor- 
 phous, H\^ocrateriform, or Salverf-orm, as in the flower of the coffee 
 (Fig. 101). A corolla which is bell-sha])ed is called Campanulate 
 (Fig. 93). Of this there are two sul)-forms, the Open (Fig. 91) and the 
 Contracted (Fig. 95). The term Globular or Globose is self-explanatory. 
 It may be specified, however, that the mouth must be small and with 
 no conspicuous limb, or with the limb turned back flat against the 
 body. Approaches to the globular form are called Sub-globular or 
 Globoidal. Other related forms are the Ovoid or egg-shaped and 
 oblong. A somewhat globoidal form, with conspicuous recurved 
 margins, is Urceolate or Urn-shaped (Fig. 102). Of the broader or 
 more widely expanded forms, the campanulate develops outward into 
 
TERMS I X 1)1 ( 'A TI Xd I RREd ll.A RI T Y 
 
 55 
 
 tlic llcinisphcrical and the C'ratcritorin or Sau('('r-.slia])ccl, as in the 
 Kalmia (Fig. 103). When still more flattened out it becomes Rotate 
 or Wlieel sha])ed, as in the SoIa}iiiin (P^ig. 92). 
 
 A ganiopetalous corolla sometimes has a fissure on one side extending 
 nearly or entirely to the base as in the Lobelia (Fig. 9G). When in 
 addition the corolla or the split portion of it loses its tubular form, 
 becoming flattened out, it is called Lignlatc or Strap-shaped, as in the 
 Dandelion (P^ig. 104). 
 
 Special Formx of I'triyoiie. — Fig. 92. Rotate corolla of Sola/mm, with connivent anthers. 93. 
 Campanulate corolhi of Campanula. 91. Prismatic calyx and bilabiate, personate corolla of Mimulus: 
 a, the tube; b, the throat; c, the lower lip; d, the palate. 95. Contracted campanulate corolla of 
 Leucolhoe. 96. Fissured corolla of Lobelia. 97. Infundibular corolla of Spiorlia. 98. Hypocrateri- 
 form corolla. 99. Cylindrical corolla. 100. Hypocratcriform corolla of Erhiles with portion of tube 
 constricted. 101. Hypocratcriform corolla of coffee flower. 102. Urceolato corolla of Pemettya. 
 103. Crateriform corolla of Kalmia. 104. LiKulate corolla of Taraxacum. 
 
 Accuracy Required in the Use of Terms.— The applicability to the tube 
 and limb separately of many of the terms here applied to the entire 
 corolla is apparent. It should be noted, however, that very detailed 
 descriptions of these res])ective parts, as well as of the throat, with 
 specification of any irregularities and marks, are often imperatively 
 demanded. This is es])ecially true of the florets of the Compositae, 
 where such cliaraetcrs, although \'ery slight, fr{>(|ueiitly serve for si)ecific 
 distinction. 
 
 Special terms for forms resulting from the possession of a])pendages 
 will be considered hiter. 
 
 Terms Indicating Irregularity. — Terms indieating irregularity will next 
 be considered, commencing with those ai)plicable to the entire body. 
 
 Either the base or the mouth is ()bli{(ue when a plane transecting 
 it is not at right angles to the lloral axis. The body is declined (Fig. 
 
56 
 
 THE PERIGONE 
 
 107) when, either with or without any manifest curve, its axis is turned 
 from the perpendicuhir, so that it rests more or less against one side of 
 the cal^-x. It may be Straight or Curved, and the curvature may be 
 Simple (Fig. 99) or Compound as in the Sigmoid calyx of Aristolochia 
 (Fig. 106). When dilated upon one side only it is Ventricose, as in 
 some species of Salvia (Fig. Ill), or, if the swelling is small and prom- 
 inent, Gibbous (Fig. 107, a). When the swelling is carried downward, 
 so as to form a sac, as in Cypripediuvi (Fig. 112, a) it is called Saccate. 
 When the dilation is directed upward, so as to form a hood, as in Aconite 
 (Fig. 108, a), it is called Cucullate or Galeate, and when the hood is 
 
 //^ //s 
 
 //£ m 
 
 Fig. 105. One-lipped corolla of Dinoseris. 106. Sigmoid-curved calyx of Aristolochia. 107. Corolla 
 of Achimenes, the mouth oblique, the base declined and gibbous. 108. Galeate upper petal of Aconite. 
 109. Personate corolla of C/ieZone. 110. Papilionaceous corolla of La^^2/r«s. 111. Ringent and gibbous 
 corolla of Salvia. 112. A saccate lower petal of Cyprip^dium. 113. Auricled calyx of Nicandra. 
 114. Dorsal spur on petal of Myrmephytum. 115. Long-caudate petals of Theobroma. 
 
 compressed laterally and much enlarged proportionately to the size of 
 the body it is called Cristate. Most of these terms are also applicable 
 to a single lip of the form next to be considered or to a petal. When 
 one or more of the lobes of a corolla are separated by a deeper sinus 
 than those of the others it is called Labiate or Lipped. If the fissure 
 proceeds entirely across the corolla, cutting off the lower portion, it 
 becomes One-lipped (Fig. 105). Otherwise it is Bilabiate or Two-lipped 
 (Fig. 111). The two lips are denominated respectively the Upper or 
 Inner (a), being that which is nearer the stem of the plant when the 
 flower and its stem are standing erect and without any twisting, and 
 
THE AURICLE 57 
 
 the Lower or Outer {h). It is always of iiii])ortaiice to note the number 
 of lobes inchuled in each Hp, in doinf; which the student may be misled 
 either by chorisis, one or more extra lobes making their appearance, 
 or, far more frequently, by cohesion, two lobes coalescing into one so 
 as to simulate suppression. Two forms of the bilabiate corolla are 
 commonly recognized — the Ringent in which the lips stand widely 
 apart (Fig. Ill), and the Personate, in which the mouth is occluded 
 (Fig. 109). 
 
 Several distinctive titles are applied to flower-forms which are 
 characteristic of large and important families or sub-families, the 
 Labiate being one. Another is the Papilionaceous, in reference to its 
 simulation of the form of a butterfly (Papilio), as in the common Pea 
 (Fig. 110). The five petals are as follows: Two (a) are more or less 
 coherent by their lower edges to form the Body or Keel; two others (6) 
 are denominated the Wings; the fifth (c) is large, broad, and commonly 
 reflexed so as to ajjpear erect, and is called the Vexillum or Standard. 
 
 Caryophyllaceous and Cruciferous Corollas. — Special names have also 
 been applied to the choripetalous corollas characteristic of the pink 
 and mustard families. The former, the Carophyllaceous corolla (Fig. 
 72), consists of five petals, each with a long, slender claw extending to 
 the summit of an elongated calyx, and there expanding abruptly into 
 a broad limb. The other, the Cruciferous corolla, has four petals, of 
 similar structure and form, so placed as to present the form of a cross. 
 
 Appendages. — Appendages to the perigone, while less numerous and 
 varied than in the case of the other organs, call for our careful attention, 
 as they sometimes occasion false interpretations. In the sense in which 
 the term is here emi)loyed, we do not refer to hairs and similar out- 
 growths which modify the surface of the parts, and which pertain 
 equally to other parts of the ])lant, but to developments which pertain 
 distinctly to the flower, modifying its structure or functions, or com- 
 monly both, in some important way. 
 
 The Auricle. — In Nicandra (Fig. 113) we observe a slight appendage 
 at the base of the calyx-lobe on either side and directed downward. 
 Such an appendage, because of its resemblance to the lobe of the ear, 
 is called an Auricle. Its appearance is somewhat exaggerated in this 
 case, owiiiu: to tlu- fact that the calyx is inflated. Smaller auricles are 
 seen at the base of the calyx of Lobelia (Fig. 1 ");'>) . A similar a])pendage 
 is sometimes directed upward, and by its union with the contiguous 
 one forms an organ exactly resembling an intermediate or false sejial, 
 as in the Strawberry (Fig. 30). Such ai)pendages, which undergo 
 
58 THE PERIGONE 
 
 considerable variation in form and consistency, may or may not be 
 stipular in their natnre. Marginal teeth extended into conspicuous 
 appendages have already been referred to. 
 
 The Cauda or Tail. — Sometimes the apex is similarly prolonged into a 
 Cauda or Tail, an extremely exaggerated form of which is sometimes 
 seen (Fig. 115). 
 
 The Awn. — An apex extended into an acute, stiff", slender point is 
 an Arista or Awn (Fig. 78, a). An awn sometimes emanates from the 
 producing organ at the back, instead of at the apex, and is then called 
 a Dorsal Awn. 
 
 The Horn.— An awn-like body which is hollow is a Cornu or Horn 
 (Fig. 150, a). 
 
 The Spur. — A horn-like appendage extending downward is called a 
 Calcar or Spur (Fig. 65). The spur may also be dorsal (Fig. 114). All 
 of the appendages noticed above may be found upon either calyx or 
 corolla. 
 
 The Fornicate Corolla. — Sacs to the corolla are sometimes intruded, 
 as in Mertensia (Figs. 118 and 119), instead of extruded. The corolla 
 is then said to be Fornicate. Instead of sacs there may be longitudinal 
 folds, as in some species of Gentian. 
 
 The Palate. — When a single large sac occludes the mouth of a bilabi- 
 ate corolla it is called a Palate (Fig. 94, d). 
 
 jNIany appendages such as we have noticed are secretory in function 
 and they may even be glandular in form. Doubtless the various 
 secretions are characteristic, and might, in pharmacy, in exceptional 
 cases, be utilized for diagnostic purposes, but the attempt has never 
 yet been made. 
 
 The Corona or Crown. — Lastly, we note what is perhaps the most 
 important, as it certainly is the most striking and interesting, of the 
 corolla or calyx appendages — namely, the Crown. The crown is an 
 outgrowth, more or less membranaceous, from the face of the perigone. 
 Its morphological nature is not understood or agreed upon, and is 
 probably not the same in all cases. It may be a mere abnormal product 
 of median chorisis, or it may be the homologue of the ligule of certain 
 leaves, hereafter to be considered (see h in Fig. 4G5, .1), the latter being 
 regarded as a normal and morphologically distinct part. When the 
 crown develops from a petal with a distinct narrowed basal portion, 
 which may be assumed to correspond to the petiole of the formative 
 leaf, it usually develops from or near the point where this is joined 
 to the broader portion (Fig. IS). The crown becomes very important 
 
PRAEFLORATION 
 
 50 
 
 ill classification in such families as Passifloraceae (Fij?. 110, a), Asclc- 
 ])iadaccac, and AiiKiri/llidaccac (Fif?. 117, a). A ring of intruded folds 
 at the throat (Fijj;. 119) is often, jjcrliaps incorrectly, called a crown. 
 It is sometimes very difficult to deterniine whether the crown is an 
 appendage of the corolla or of the androecium.' Its adhesion is some- 
 times to the androecium and not to the corolla, and sometimes to both. 
 In some species of Passi/lom which have no corolla, the attachment 
 is to the calvx onlv. 
 
 //a 
 
 Fig. IIG. T,i>nKitutlinal section, throviKli flower of Passiflora oxliihiting orown at a. 117. Flower of 
 Narcissus exliibiting a. large crown at a. US. Flower of Myoyotis. 11',). The same opened to sliow 
 folds in throat. 
 
 Praefioration. — The arrangement of the ])arts of the perigone in the 
 bud yields some of our most important diagnostic characters as dis- 
 tinguishing families, sub-families and genera, and has been the subject 
 of elaborate classification. The demands of pharmacognosy, however, 
 call for attention to only the princii)al types of Praefioration or Aesti- 
 vation. The three principal types depend upon the fact that the com- 
 bined breadth of all the ])arts of a perigone circle must (1 ) be insufficient 
 to enclose the i)U(l, in which case ()])en s])accs must be left between 
 their margins {Rr.srdd) or the summit must be left uncovered (the calyx 
 in P^ig. 120), the form in either case being called Open; (2) it must be 
 exactly sufficient to enclose it, the edges then meeting exactly, with 
 nothing to spare and the form being called Valvate (Fig. 12;), the calyx); 
 or {'.]) it must be excessive, in which case the excess may be dis])()sed 
 of in one of several ways. In one, the parts, after nuH-ting s(iuarely, 
 ar<' uniformly turned straight outward (Fig. 121), the form being 
 called Valvate Reduplicate. In another, they are turned straight 
 inward, the Valvate Iiiduplicate form (Fig. 122). They may even be 
 
60 
 
 THE PERIGONE 
 
 rolled inward, the Involute form. When lapping the one o^•er the 
 other they are Imbricate (Fig. 123, the corolla). Here it is important 
 to note whether the overlapping is from right to left, Dextrorse (Fig. 
 125), or the reverse, Sinistrorse (Fig. 124). In determining this point, 
 the relations can best be understood by imagining the flower as a man, 
 his feet in the direction of the torus and his hands representing the 
 petals. To be dextrorse, his right hand must be covered by his left. 
 In other words, the terms "right" and "left," in this position, signify 
 right-covered and left-covered, not right-covering and left-covering. 
 
 /Z3. /2& 
 
 Fig. 120. Bud of Ipomoea with open calyx and convolute corolla. 121. Transverse section through 
 valvate reduplicate calyx of Hibiscus. Fig. 122. The same, valvate-induplicate calyx of Clematis. 
 124. Sinistrorse imbrication of corolla-lobes of Lochnera. 125. Dextrorse imbrication of corolla- 
 lobea of Echites. 
 
 Petals, sepals, or stamens are occasionally rolled vertically down- 
 ward from the apex, this form being called Circinate. Occasionally we 
 find the petals folded and doubled in an irregular manner, the Crumpled 
 or Corrugated form of praefloration. A number of terms are called for 
 by the peculiar conditions of the gamopetalous form. Economy of 
 space is here commonly secured by longitudinal folding, the Plaited 
 form. Vertical shortening is often secured by twisting, the Convolute 
 form (Fig. 120, the corolla). In this case it is important to determine 
 the direction of the contortion as dextrorse or sinistrorse, in the same 
 way as that of imbrication. 
 
 Other details as to the precise mode of overlapping are frequently 
 worthy of note. 
 
 In determining the form of jjraefloration, care must be taken to 
 select a well-formed bud. 
 
 The Mixed Form. — The praefloration may be mixed, as in Oenothera, 
 where the parts^^are valvate at the base and slightly imbricate or redu- 
 plicate at the immature apex. At the best, intermediate and perplexing 
 forms will be encountered. 
 
DURATION 61 
 
 Duration. — The duration of the perigone, especially of the calyx, 
 is frequently of considerable importance from the standpoint of phar- 
 macognosy, although in general not so. When a part falls away at, 
 or very shortly after, expansion it is Caducous. When lasting about 
 a day, and then either falling or i)erishing upon the flower, as in the 
 poppy, it is Fugacious. When lasting longer than a day, but falling 
 soon after fertilization, it is Deciduous. When remaining and retaining 
 more or less of its normal appearance for some time after fertilization, 
 it is Persistent. When so remaining, but in a withered condition, it is 
 Marcescent. These definitions assume that fertilization takes place 
 normally. If this be artificially prevented or deferred, the freshness of 
 a corolla is often very greatly })rol()nged. (See Fertilization.) Impor- 
 tant facts relating to the Accrescent calyx of the fruit will be i^resented 
 when the latter is discussed. 
 
 Some very interesting facts concerning characteristic movements 
 of the corolla, its sleeping and awakening and other habits, should be 
 sought in general works on botany. 
 
CHAPTER V 
 
 THE ANDROECIUM 
 
 Review. — It has already been shown, in considering the general 
 nature of the flower, that in at least a large part of the flowering class, 
 the androeciiim typically consists of two stamen-circles, the stamens 
 of each isomerous with the parts of the other circles, one standing in 
 front of each petal and sepal, that each stamen is entirely free and 
 distinct, and of characteristic form and structure (Figs. 12 and 14). 
 We have also pointed out some of the forms of deviation due to 
 duplication, suppression, adhesion, and metamorphosis. To these the 
 following general remarks may be added. 
 
 Sterile Filaments and Anthers. — When an anther, still present, has 
 lost its function, it is called a Sterile or Imperfect Anther. When the 
 anther has become suppressed, but the filament remains, the latter is 
 called a Sterile Filament. Either of these is called a Staminodium. 
 One or more complete circles of sterile filaments, changed or not by 
 metamorphosis, may be mistaken for a crown or a disk (Fig. 38). 
 Adhesion of the stamens to the corolla, or even to the ovary, may 
 include only one circle, the other circle being entirely free, or they may 
 be adnate in different degrees (Fig. 44). 
 
 Terms Indicating the Number of Stamens. — Before discussing other 
 and specific points of variation, we shall consider the typical organ 
 more in detail. The number of stamens in the androecium is indicated 
 by joining the appropriate numeral to the suffix "androus;" thus, 
 Monandrous, Diandrous, Triandrous, Tetrandrous, Pentandrous, etc. 
 These terms do not necessarily indicate the numerical ])lan of the flower. 
 When the number is 20 or more, the term Polyandrous or Stamens 
 Indefinite is commonly employed. 
 
 Color. — In color, the filament is commonly white or whitish, and 
 the anther yellow; but this is not an absolute rule, as the latter is often 
 blue, brown, black, or otherwise colored. 
 
 Construction of the Anther. — There are several distinct forms of attach- 
 ment of the anther to its filament which are characteristic of larger or 
 smaller groups. Its origin from the leaf assumes that each theca 
 corresponds to a vertical half of the leaf from which it has developed. 
 
ATTACHMENT OF THE ANTHER 
 
 63 
 
 and the production of a sccoiHlan- or "false" i)artition separating each 
 theca h)ngitudinally into two locclli. This inipHes a four-h)cellatc 
 condition of all anthers (Fig. K)S). Ordinarily this condition is not 
 permanent, the false septa more or less completely (lisa])i)earing after 
 the formation of the pollen, leaving the mature, antlier two-celled, or 
 this condition is brought about in other ways. 
 
 Attachment of the Anther. — The Adnaic Form.— It is furthermore 
 assumed that the filament is normally continued along the back of 
 the anther in the relation of the midrib of the formative leaf. This 
 form of attachment is called Adnate (Fig. ]2()). 
 
 Fig. 126. Adnate anther of Magnolia. 127. An incumbent anther. 128. Twisted anther of Ceiba. 
 129. Versatile anther of Oenothera. 130. Innate anther of Sangumaria. 131. Reniform confluent 
 anther of Malva. 132. Horizontal confluent anther of Pcnlslemon. 133. Sagittate anther of Taber- 
 
 naemontana. 
 
 Iiicinnhctit Form. — It ma>' be attached only at some ])oint u])()n the 
 back (I)orsifixed). Of this there are two forms. In one (Fig. 127) the 
 anther is rigidly fixed, its lower portion close to and ])arallel with but 
 free from the upper portion of the filament, the Incumbent form. 
 
 ]'ers(iiUe Form. — In the other, it moves freely upon the pivotal 
 l)()int of attachment (Fig. 129), the Versatile form. Rarely the anther 
 is wrapped or twi.sted about its filament (Fig. 128). 
 
 Innate Form.— Thv continuation of the filament, instead of being 
 along the back, may be centrally up through the base and between the 
 thecae (Fig. 130), the Innate form. 
 
 SiiKjiiidtc Form. — The lower ])ortions of the thecae may be separated 
 from one another and from the connective (Fig. 13.3), the Sagittate form. 
 
 Reniform (inti Ilor/'jnifdl Form.^-. — The sagittate condition is some- 
 times extreme, the antliers becoming more or less reiiifonn (Fig. 131) 
 or semicircular, or tlicy may e\fii become liori/.ontal I l''ig. 132). This 
 
64 THE ANDROECIUM 
 
 is to be distinguished from the form which is horizontal by versatility 
 (Fig. 129), by the presence in the latter of the two cells side by side, 
 in the former, end to end. 
 
 Extrorse and Introrse Attachments.- — Rarely the adnate form will 
 possess the connective upon the inner side (next the pistil), when it is 
 Extrorse by Attachment, in the normal form being Introrse. 
 
 Forms of the Filament. — Besides these variations in the relation of 
 filament and anther, each is in itself subject to certain modifications, 
 some of which will be discussed in connection with appendages and 
 exaggerated growth. The general form of the filament is subject to 
 much variation which, being characteristic in a given species or genus, 
 requires specification. When cylindrical, either of uniform thickness 
 throughout or regularly tapering, it is Terete. When considerably 
 thickened toward and at the summit, so as to be club-shaped, it is 
 called Clavate. When flattened it is Complanate. Laterally Com- 
 planate is so flattened that the edges point toward and from the gynae- 
 cium, the broad sides to right and left. Dorsally complanate has the 
 edges pointing to right and left, the broad sides facing toward and from 
 the gynaecium. A dorsally complanate filament may have a sharp 
 ridge or keel running along its back, when it is called Carinate or Keeled. 
 If the ridge is less sharp and prominent it is Costate or Ribbed. It 
 may, upon the other hand, bear a groove, when it is called Channelled. 
 Rarely a filament is Triangulate in cross-section, or otherwise prismatic. 
 When tapering from a broad base to a rather acute apex, and rather 
 short, it is Subulate or awl-shaped. When very slender or thread- 
 shaped, it is filiform. When even more slender so as to be hair-like, 
 it is Capillary. 
 
 Forms of the Anther. — The principal forms of anther are oblong, oval, 
 globular, reniform, quadrangular, or linear, and the base or apex may 
 be truncate, rounded, obtuse, acute, or pointed. An anther is occa- 
 sionally doubled upon itself, when it is styled Sinuous (Fig. 139). It 
 may even take the form of a horizontal ring (Fig. 134). This condition 
 is sometimes preceded by the loss of one theca. In any case of curva- 
 ture, even slight, of the anther, the same is characteristic and of value 
 in classification, as exemplified in the vast genus Solanuvi, where 
 attention to this character is well nigh indispensable. The filament is 
 also sometimes variously curved or reduplicate, and this condition may 
 be permanent or only temporary during the early stage of the flower, 
 as in Ardostaphylos (Fig. 145), where the powerful elasticity of the 
 filament assists in expanding the corolla. 
 
J.\TR()/iSK A\D EXTliOR>SK DI'JII ISCKXCK 
 
 05 
 
 Development of the Spores. — Inside of the tlicca, develop certain 
 large cells, in rows, the Spore INIother Cells, each of which, by t)\ice 
 dividing, produces a Tetrad of four pollen-grains. Ordinarily the wall 
 of the mother-cell mostly (lisa])i)ears and leaves the grains separate and 
 mobile, while in other cases they cohere in the tetrad or in a cluster 
 of tetrads. 
 
 Pollinia and PoUinaria. — Large clusters are called Pollinia or Pollen- 
 masses. The entire contents of a theca may form one pollinium (Fig. 
 135), or they may be divided into several (Fig. 140). A cluster of 
 pollinia, like the last, is called a Pollinarium. The number of pollinia 
 
 
 Fig. 134. Ring-formed anther of Cyclanthera. 135. Pollinium of Asclepias. 136. Dorsal dehiscence 
 in anther of Hyoscyamus. 137. Dehiscence by apical pores in Menzicsia. 138, Dehiscence by valves 
 in anther of Sassafras. 139. Sinuous anther of Sicyos. 140. Pollinarium of 4 pollinia in Ponthiera. 
 141. Marginal dehiscence in anther of Convallaria. 142. Ventral dehiscence in anther of tomato. 
 143. Dehiscence by apical pores in anther of Cassia. 144. Peculiar ventral pores. 145. Apical pores 
 becoming basal by inversion of the anther in Arctostaphylos. 
 
 in a theca is of much diagnostic importance in tlie Orchidaceae, The 
 characteristics of the individual ])()llen-grains are of the utmost value 
 in pharmacognosy, as well as in classification (as, for instance, in the 
 Acanthaceae) , and arc discussed in works on histology. 
 
 Dehiscence of the Anther. — ^We must next consider the structural 
 provisions for permitting the escape of the pollen from the thecae or 
 locellae. This is commonly by splitting, called Dehiscence, along a 
 longitudinal line upon each theca, called the Suture. If the suture is 
 at the back of the anther, as in Ilyoscyamns (Fig. 136), the dehiscence 
 is called Dorsal. If upon the face, as in the tomato (Fig. 142), Ventral; 
 if upon the i^^h^(.\ as in Coiirdllaria (Fig. 141), ^Marginal. 
 
 Introrse and Extrorse Dehiscence. — This suture may face the gynae- 
 cium, when the anther is Introrse by Dehiscence, or away from it, 
 5 
 
66 THE ANDROECIUM ^ 
 
 Extrorse by Dehiscence. It does not follow that an anther introrse or 
 extrorse by dehiscence is the same by attachment. 
 
 Confluent Sutures. — In the sagittate-horizontal anther the sutures 
 of the two thecae often become continuous, the Confluent form (Figs. 
 131 and 132). 
 
 Dehiscence by Pores. — Small orifices, called Pores, frequently exist at 
 the apex, as in Ca.s-.sia (Fig. 143), more rarely at the base. The most 
 scrupulous care must be taken to determine the exact direction in which 
 apical pores look. In some cases, as in Solanum, a slight difference 
 will possess specific importance. 
 
 Dehiscence by Valves. — A less common form of discharge is by A^alves 
 (Fig. 138), the common form for the four-locellate anther. Special 
 mechanical contrivances for aiding in the discharge of the pollen are 
 of great interest and will be mentioned under Cross-pollination. 
 
 Cohesion. — Cohesion is responsilile for quite as great and important 
 modifications of the androecium as of the perigone. Here, as there, it 
 may be complete, or, beginning at either apex or base, it may stop at 
 any point. Fig. 84 displays the dilated bases of the filaments of 
 Lysimachia lightly coherent, the detection of the condition calling 
 for the same keen inspection as in the case of the corolla. In Guarea 
 (Fig. 147) the union is seen carried to the anthers, but these left 
 distinct. 
 
 Adelphism. — Coherent filaments are styled Monadelphous when all 
 united (Fig. 147), Diadelphous, when there are two groups, even though 
 one of them contains but one stamen, as in Glycerrhiza (Fig. 146), 
 Triadelphous when three, and so on. It must not be lost sight of that 
 the terms are applied similarly, w^hether the iniion is progressive, the 
 result of cohesion as in this case, or that of incomplete chorisis, as in the 
 Tilia (Pigs. 34 and 37) and Psorospermum (Fig. 38), though its classi- 
 ficatory value is very different in the two cases. 
 
 The Stamen-column. — The term column, previously explained, is 
 changed to Stamen-column for monadelphous stamens. 
 
 The Ssmandrium. — The stamen-column is ordinarily hollow, contain- 
 ing the Gynaecium; but when the flower is staminate, the column is 
 solid, and called a Synandrium. 
 
 When, as seen in Fig. 92, the anthers come together but do not actually 
 cohere, they are called connivent. The cohesion is carried only partly 
 down the filaments in the squash (Fig. 148), and partly upward in the 
 Sidalcea (Fig. 149), but in the Asdepias (Fig. 154) it is complete for 
 the entire organs. 
 
APPEND AGING 
 
 C7 
 
 Asymmetry and Irregularity. — A lack of symmetry aiul regularity, 
 
 actinu' sci)arately or tout'tluT, is responsible for a number of character- 
 istic and iinpoi-tant states of the androecium requiring,' distinctive 
 terms. 
 
 The Didynamous Androecium.- In the o-merous flower of ScidcUarid 
 (Fii;-. l")!) six stamens are su])pressed and the rcniaininijj four are 
 irr('<;ulai-, there being a pair of each form. This foi-ni of anch'oeciiim 
 has received the title of Didynamous. In this case the antlicrs of a j)air 
 are connivent also. 
 
 /J4 
 
 Fig. 140. Diadelphous arulroerium of Glycyrrhiza. 1-17. Vertical section lliroiigh flower of Guarea, 
 showing nionadelphous filaments witli distinct anthers. 148. Cohesion of filaments, incomplete at 
 base, in flower of squash. 149. The same, incomplete at summit, in flower of SiV/afcca. 150. Vertical 
 section through flower of Asdepias showing coherent filaments and anthers, with appendages to crown 
 in form of horns. 154. Winged androecium of same. 151. Didynamous androecium of Labiatae 
 152. Androecium of Eupatorium, the anthers coherent, the filamenta distinct. 153. Monadelphous 
 filaments and anthers of Lobelia. 
 
 The Tetradynamous Androecium.^In that of the IMustard (Fig. 33), 
 two of the stamens Iuinc each by chorisis become converted into two, 
 these differing in length from the undi\i(led pair. 'J'his form is styled 
 Tetraflynanions. 
 
 Appendaging. No other subject connected with the androecium calls 
 for such close and discriminating attention in connection with pharma- 
 cognosy as the i)roducts of exaggerated growth and enation. No 
 portion of the androecium is free from their effects, which ai)ply equally 
 to it when adherent or coherent, free or distinct. The simplest form 
 of appendage to the filament is that of sti])nloid a])])endages to the 
 
68 
 
 THE ANDROECIUM 
 
 base, called Petaloid when assuming the form of a petal, as in Fig. 155 
 A similar appendage may stand in front of a stamen. One standing in 
 front of a stamen group has been shown in Fig. 37. Appendages may 
 be developed at a higher point in other cases. Appendages in the form 
 of teeth or hairs are very common. 
 
 Modifications of the Connective. — Modifications of the connective are 
 numerous and remarkable. The thickening of its entire body, equally 
 or unequally, produces such appearances as are seen in Figs. 15G, 157, 
 and 159. Or the extension may result in elongation either above or 
 below the thecae, instead of in broadening. 
 
 /SS. 2S6 ISZ IMJ60 
 
 Fig. 155. Petaloid appendage to filament of Chaetostoma. 156, 157, and 159. Anthers with the con- 
 nective broadened so as to separate the thecae. 158. The same with the broadened connective forked. 
 160. Stamen with connective extended between the apex of the filament (a) and the base of the anther 
 (6). 161. The same, with an appendage at base of connective. 162 and 163. The appendage with 
 scarcely any elongation of connective. 16-4. Forked connective of Salvia, each branch bearing one of 
 the thecae. 
 
 Basal Appendages. — If the extension is downward, it will lead to an 
 apparent jointing of the filament (Fig. 160), the space between a and b 
 being such a downwardly produced extension of the connective. A 
 slight bulbous enlargement at the base may be modified into the most 
 grotesque forms, as shown in Figs. 161 to 163. Such appendages, in 
 every detail of number, form, position, and direction, are characteristic, 
 and in a family like the Melastomaceae, from which most of the above 
 illustrations are taken, possess generic value. Instead of elongating 
 as a single body, the base may* apparently divide longitudinally, through 
 extreme broadening, resembling a forked filament, one theca borne on 
 each branch (Figs. 158 and 164.) 
 
 One-celled Anthers. — When one of the thecae then becomes suppressed, 
 its connective branch remaining (Fig. 165) or even disappearing (Fig. 
 166), one of the forms of the one-celled anther results. Another form 
 is produced by simple abortion, without any such modification of the 
 connective, or it may result from the disappearance of the connective. 
 
APPENDAGES TO THE STAMEX COIAMX 
 
 G9 
 
 Dorsal Appendages.— Instead of the base, tlie back of the connective 
 may l)e api)cii(Ia<;c(l. It may become expanded into a disk-like form 
 over the backs of the thecae, as in Gratiola (Fig. 1()7). The backs of 
 the anthers may be excavated to receive it, as in Aloe (Fig. 108), or it 
 may be ap})en(higed in any other direction. 
 
 Apical Appendages. — Appendages of any form may devek)p at its 
 ai)cx. In tlie Compositae these are frequently triangular, as in Eupa- 
 toriuvi (Fig. 109, a), or lance-shaped. In the Asariim (Fig. 170) it is 
 an awn, while in the Violet (Fig. 171) it is sail-shaped. Sometimes 
 it is formed like a feather (Plumose). 
 
 Fig. 165. Forked connective, one of the thecae aborted. IGG. The same as in Audibertia, with one 
 of the branches aborted. 167. Anther of Gratiola, the connective expanded into a saucer-shaped disk. 
 168. Anther of Aloe, the connective hollowed to receive the filament. 169. Anther of Eupatorium, 
 the connective bearing a terminal appendage. 170. The same, as in Asarum. 171. The same, as in 
 Viola. 172. Anther of Vaccitiium, the thecae extended into awns and bearing also dorsal awns. 173. 
 Monadelplious filaments of Alternanthera bearing fimbriate appendages in the sinuses. 
 
 Appendages to the Thecae. — It remains to be pointed out that the 
 thecae themselves may be similarly appendaged at any part. Fig. 133 
 displays caudae, or tails, which are found in a great variety of forms. 
 In Fig. 154, a, Alae, or wings, are illustrated. Dorsal spurs or claws 
 (Calcaria) frequently occur and are also often borne at the top. Apical 
 awns to the thecae, forked and pore-bearing at the summit, as well as 
 dorsal awns, are also shown in Fig. 172. 
 
 Appendages to the Stamen-column. — The stamen-column itself is 
 subject to reinarkai)le and characteristic appendaging, with or without 
 connection with an adnate disk. Ordinarily, the summit of the stamen- 
 tube terminates at the beginning of the distinct i)ortion of the stamens, 
 but sometimes, as very generally in the Amaranthaccae (Fig. 173), it 
 is continued ui)ward in the sinuses of the anthers, and this j)()rti()ii may 
 be lobed and appendaged in the most beautiful manner. 
 
 Stamens which extend beyond the margin of the coiojla are called 
 Exserted or Plxsert. This term is also ai)plieable to any organ which 
 projects beyond the perigone. 
 
CHAPTER VI 
 
 THE GYNAECIUM 
 
 Gymnospermous and Angiospermous Gynaecia. — Two distinct types 
 of the gynaecium respectively characterize the Gymnosperms and the 
 Angiosperms, both of which classes contribute important medicinal 
 plants. What has been said of the gynaecium in our consideration of 
 the general nature of the flower, pertains wholly to the latter class. A 
 few words concerning the former may be written before taking up our 
 detailed study of the latter. 
 
 The Gymnospermous Pistil. — The essential character of the gymno- 
 spermous pistil is illustrated in Fig. 174. This consists in its not being 
 shaped into an enclosure for containing the ovules. In the form here 
 
 figured there is no progress toward 
 such a condition, the carpel remain- 
 ing more or less fiat and bearing the 
 ovules upon its surface; but in the 
 progressive forms there is a cavity, 
 which, however, is never completely 
 enclosed. A high development of it 
 is found in the Taxus or Yew (Fig. 
 175), in which the cavity is deep and 
 
 Fig. 174. Entirely plane gymnospermous OpCU Ouly at the Very apCX. The 
 
 pseudo-cavity of the gymnospermous 
 carpel is never divided. It is evi- 
 dent that no true style or stigma can exist in this class of plants, 
 although it must be understood that there is an organ performing the 
 same function of providing for the germination and growth of the 
 microspore, the possession of such an organ being the one distinction 
 between the flowering and flowerless plants. 
 
 Review. — It has been shown that the gynaecium of Angiosperms, 
 except in those rare cases in which a central appendage of the torus is 
 projected u])ward, occupies the center or summit of the flower; that it 
 consists of one or more carpels or carpophylls which may be all coherent 
 into a single ])istil, the Syncarpous, Gamocarpous or Compound Pistil 
 (Fig. 2 IS, etc.), or may each form a separate pistil, the Apocarpous, 
 
 carpel of Pinus. 175. Cup-shaped gymno- 
 spermous carpel of Taxus. 
 
METHOD OF KXAMIXATJOX 71 
 
 Monocarpellary, orSiini)le Pistil (Figs. 219 and 220), and tlint ordinarily 
 the carpels alternate with the stamens of the adjacent circle. The parts 
 of the pistil have been defined, and it has been shown that of these the 
 stipe or thecaphore is rarely present, and that the style is very fre- 
 quently absent, resulting in the Sessile Stigma. The different forms of 
 adhesion and its effects, as well as those of suppression and metamor- 
 phosis, have also been explained. Some additional facts of a general 
 nature must be considered before taking up the details of this subject. 
 Method of Examination. — The student should from the outset resist 
 the temi)tation to seek the characters of the gynaecium in the mature 
 or immature fruit, because of its more convenient size. While many 
 of the characters of the gynaecium are permanent, there are others 
 which (lisai)])ear after the fertilization of the ovules, and still others 
 which only then make their appearance. The other ])arts of the flower 
 should be completely stripped oft", this operation being performed under 
 close and continuous scrutiny, with the idea of detecting any character- 
 istics of relationship between them and the gynaecium. The latter 
 should then be carefully examined in situ. An implement should be 
 passed down between the carpels to determine what degree of cohesion, 
 if any, exists between them, for this will occasionally be found at the 
 very base only, and also to determine if there be any adhesion to a 
 central prolongation of the torus. The details of attachment to the 
 torus must also be determined and their arrangement considered. 
 When numerous, the pistils are apt to assume the spiral arrangement, 
 which has already been noticed in referring to the position of floral 
 l)arts in general. When solitary, the carpel assumes a position to one 
 side of the axis, thus demonstrating its isolation through the suppres- 
 sion of the complementary ])arts of the circle. A lack of uniformity, 
 as indicating abortion of one or more carpels, must be looked for. 
 When all are uniformly aborted, in the case of flowers which are herma- 
 j)hro(lite but imi)crfect, this fact will sometimes escajic detection unless 
 both forms of flower are examined. The color, texture, and surface of 
 the carjx'Is call for minute exaiiiination in all cases, though there are 
 no peculiarities of a general nature diil'ering from those of the other 
 organs. As in the case of the petals, so in that of the carpels, the general 
 form is determined by that of the foliage leaves; but the form is less 
 closely preserved and the homology is far less a])])arent here than there, 
 owing to the far more ])r()foun(l modifications which are rendered 
 necessary by the j)eculiar functions of the carpels, a consideration which 
 will further on be seen to a])])ly with special force to tin- fruiting stage. 
 
72 
 
 THE GYNAECTUM 
 
 Position of the Style.— The position of the style often calls for scrutiny. 
 It does not always rise, as would be expected, from the summit of the 
 ovary. One process by which deviation in this particular results is 
 illustrated by Fig. 17(5, which represents the deeply lobed ovary of 
 borage, the single style rising from the depression in the center. If, 
 now, all but one of the parts of such an ovary were to become aborted, 
 the style would be seen rising more or less laterally (Figs. 177 and 
 178), or even basally (Fig. 179) from the remaining monocarpellary 
 ovary. E\'en though the styles remain separate in such a divided 
 ovary, yet their insertion is necessarily carried toward the base 
 (Fig. 180). 
 
 m. J6'6. m js'S' /m wo 
 
 Fig. 176. Deeply 4-lobed ovary of Boraffo. 177. Lateral style on carpel of I'VZ/oresia. 178. The same 
 in Aslronium, the style almost basal. 179. The same in Alchemilla, the style completely basal. 180. 
 The same, with none of the carpels aborted. 181. Conical style of Piper. 182. Clavate style of 
 Helianlhemum. 183. Obconical and prismatic style of Bomhax, with umbrella-shaped stigma. 184. 
 Obconical style of Chimaphila. 185. Filiform styles of Poederia. 186. Style of Potalia, with large 
 bulb-like base. 187. Filiform and pilose style of Galopina. 188. Style of Heliocharis, with subulate 
 branches. 189. Styles showing a tendency to early separation below, while remaining coherent above. 
 190. Capillary style of maize. 
 
 Forms of the Style.— The same descriptive terms as to form already 
 applied to the filament apply equally to the style and its branches. 
 Owing to the frequency with which styles are coherent, ribbed, chan- 
 nelled, or angled forms are common. Fig. 181 illustrates the conical 
 style of Piper, Fig. 182, an obconical one; Fig. 183, one obconico- 
 
POSITION AND FORM OF STIGMA 
 
 73 
 
 prismatic; Fig. 184, a clavate form; Fig. 18G, one with a bulbous base. 
 The style branches in Fig. 185 are filiform; in Fig. 187 they are filiform 
 and plumose; in P'ig. 190, cai)illary, and in Fig. 188, subulate. Rarely, 
 styles will be connate above, distinct below (Fig. 189). 
 
 Position and Form of Stigma. — The position and form of the stigma 
 are of very great importance in classification. Its size, as compared 
 with that in other related plants, is apt to be greater or less according 
 as the number of ovules to be fertilized varies. 
 
 Figures illustrating forms of the stigma 
 
 The Linear Stigma. — It has already ])een sliown that while the 
 stigma is commonly located at or ii(>ar the ai)ex, it may extend either 
 entire or divided into two lines for a greater or less distance down the 
 ventral margin of the style, becoming Linear (Fig. 191). 
 
 Stigmas Introrsely Located. — If several united styles are separate 
 at the summit, or ui)i)er j)ortions, their stigmas are commonly borne 
 upon their inner faces, as in this case, and are frequently, by the co- 
 hesion of the former in the young condition, secluded from the access 
 of pollen until a certain time (Figs. 191 and 271). Between the con- 
 
74 THE GYNAECIUM 
 
 dition of complete separation and complete cohesion of several stigmas 
 there are all degrees of division and of lobing of the divisions (Figs. 192 
 to 195). 
 
 The Capitate Stigma. — ^A stigma which is strictly terminal and more 
 or less spherical, thus resembling a head, is Capitate (Fig. 196). 
 
 The Truncate Stigma. — The Capitate stigma is Truncate when it 
 terminates abruptly in a flat upper surface, as though cut across (Fig. 
 197). 
 
 The Peltate Stigma.— li flattened and attached at the center it is 
 Peltate (Figs. 183 and 198), and this may be horizontal or oblique, as 
 in the latter. The peltate stigma may have its margin reflexed, making 
 it umbrella-shaped (Fig. 199), or upturned, making it cup-shaped, or 
 Cupulate (Fig. 200), and either of these forms may be lobed (Figs. 201 
 and 202). 
 
 The Laminar Stigma. — A stigma flattened out into a blade-like form 
 is called Laminar. Several oblique laminar forms are show^n in Figs. 
 20.3 to 205. Fig. 207 displays the manner in which the stigma sometimes 
 enfolds the stamen. 
 
 The Annular »Sii^7?ia.— Stigmas sometimes possess a ring at or below 
 the apex, the Annular form, various modifications of which, unlobed 
 and lobed, are shown in Figs. 210 to 215. Such forms prevail in the 
 family Ajjocynaceae and are of great value in classification. 
 
 Appendages to the Stigma. — The Appendages of the stigma are quite 
 as numerous and varied as those of the anther. A Plumose appendage 
 is shown in Fig. 209. Such are common among the grasses. A stigma 
 (or other organ) is called Penicillate when its ])lumose appendage 
 resembles a little brush (Fig. 208). In Stigmatophyllon, the appendage 
 is a little green leaf (Fig. 206). 
 
 Terms Indicating the Number of Carpels. — The number of carpels in a 
 compound pistil is indicated by the use of the appropriate numeral 
 followed by the suffix "carpellary," thus Dicarpellary, Tricarpellary. 
 
 Determination of the Number of Carpels. — The determination of the 
 number of carpels is of the utmost necessity, but is usually a difficult 
 task for the beginner, especially if he is not pre\'iously trained in the 
 art of plant-dissection. The indications may be divided into external 
 and internal. The latter must be apprehended from the study of 
 internal structure explained below. 
 
 External Indications. — Whenever there is more than one pistil in a 
 gynaecium, each consists of but one carpel. Complete chorisis of a 
 carpel, producing more than one pistil, never exists, although it fre- 
 
IX ri'JRNA L IN Die A TIONS 
 
 75 
 
 queiitly appears so, in the fruit. If cohesion is partial, cxeii tlioiif^h so 
 nearly complete as to Icaxc a separation represented by a mere lohirig 
 at apex (Fi<;;. 21G) or dorsum (Figs. 217 and 218), the determination 
 of the mimber of its carpels is not difficult. It is true that the latter 
 condition is often complicated by grooving or pseudo-lobing pertaining 
 to the backs of the indi\i(lual carpels, but such grooves are usually 
 characteristically different from those separating the carpels. While 
 the above remarks have been applied especially to the ovary, they may 
 be applied with equal force to the styles and stigmas. If the exterior 
 of the ovary bear no indications of the number of car])els, we may 
 count the styles, or the divisions or apical or dorsal lobes of a style 
 column, and if those be wanting, then the stigmas or the corresponding 
 characters of the stigma. It must be noted, however, that complete 
 
 Fig. 21G. Ovary of Modiola, the lobes of the summit indicating the carpels. 217. TIk 
 by lateral lobing in Pentapanax. 218. The same in Tetraplasandni. 
 
 or partial chorisis of style or stigma is not at all rare, and care must be 
 taken to avoid falling into error, by counting mere parts as styles or 
 stigmas. In such case the number of lobes of each is apt to equal 
 the number of styles or stigmas. 
 
 Internal Indications. — In the case of failure of all these indications to 
 appear, the internal structure must be studied. For this purpose both 
 longitudinal and transverse sections must be made. The former should 
 be so directed as to lay open the inside of a cari)el, and of the latter 
 there should be three, through the lower, middle, and upper portions 
 respecti\-ely. In most eases a good li'iis will be sullieieiit to di.sclose 
 the charaetc-rs, but when insufficient, recourse must be had to the 
 stage and low power of a comj^ound mier()scoi)e. Further details regard- 
 ing this process will be found in our chapter devoted especially to the 
 methods of floral dissection. 
 
76 
 
 THE GYNAECIUM 
 
 First Plan of Ovarian Structure. — Two distinct plans for the enclosure 
 of the cavity of the angiospermous ovary are recognized. In the first 
 (Fig. 219) the margins of one carpel meet each other, and then, by more 
 or less of an involution, form the placenta with its two rows of ovules 
 within a single cell. If two or more of such carpels then unite in one 
 compound ovary (Figs. 221 and 222), each necessarily forms its own 
 cavity, and there are as many cells as such a pistil has carpels, unless 
 some modification of structiu'e shall take place, as illustrated below. 
 
 Axillary, Axile, or Central Placentae. — In all cases where closed carpels 
 of this sort unite in a compound ovary, their ventral sides come into 
 contact, and the placentae are brought together at the center and are 
 known as Axillary, Axile, or Central. 
 
 Fig. 219. Transverse section tlirough 1-celled monocarpellary ovary of bean. 220. The same, 
 through 2-celled monocarpellary ovary of Astragalus. 221. The same, through upper 2-celled portion 
 of dicarpellary ovary of Datura. 223. Through lower, 4-chambered portion. 222. The same, through 
 the 5-carpelled and 5-celled ovary of Vaccinium. 224. Through the 5-carpelled, but 10-celled ovary 
 of the flax. 
 
 Abortion of the Septa. — If the septa between the cells now become 
 aborted (Fig. 230), the placentae are left free in the center and are 
 collectively called the Free Placenta. 
 
 True and False Septa and Cells. — ^The walls separating the cells of 
 ovaries constructed upon this first plan, because they consist of the 
 original carpellary walls, are called "True," as are the cells. When, 
 as sometimes happens (Fig. 220), a- new septum develops from the 
 carpellary midrib, extending across to the placenta and separating its 
 two rows of ovules into two cells, the term "False" is applied both to 
 the septum and to the cells so resulting. If there be several carpels to 
 the pistil, and each undergoes this change, it is clear that there must 
 result twice as many cells as there are carpels (Figs. 223 and 224). 
 
 Chambers. — When septa are incomplete, the imperfectly separated 
 cells which result are called Chambers, and the ovary is said to be 
 Chambered. Thus the ovary of Datura is completely 2-celled (Fig. 
 221), but each cell is 2-chambered by partial walls which exist at the 
 basal portion only (Fig. 223). 
 
BASAL A^'D APICAL PLACENTAE 
 
 77 
 
 Second Plan of Structure.— Quite a diflVrciit group of appearances 
 will result from the liiii^lier or more comi)lex form of carpel union, by 
 which the ])roximate margins of two adjacent carpels meet and unite 
 (Fig. 225) instead of two belonging to the same carpel. The result of 
 this form must be a single cavity or a 1-celled .ovary, without regard 
 to the number of carpels, unless, as in the mustard (Fig. 22(1), one or 
 more false septa may divide it. 
 
 Axillary Placentae. — It has been observed that in all cases of the 
 first plan of ovarian structure, the placentae will be central. It is 
 equally clear that in all cases of the second, the placentae must be 
 formed upon the sides, where the edges of the carpels meet. Such 
 placentae are called Parietal (Figs. 225 to 229). Such placentae may, 
 by an extensive involution of the margins, be carried very nearly, or 
 quite, to the axis (Figs. 227 and 228), but unless cohesion actually 
 occurs at that p(Mnt they are parietal and the ovary is 1-celled. 
 
 ;i>26 
 
 230. 
 
 Fig. 225. The 2-carpeIled, 1-celled ovary of the gentian. 22G. 2-carpelled and falsely 2-celled ovary 
 of mustard. 227. A 2-carpeIled, 1-celled ovary, its placentae nearly meeting in the axis. 228 and 229. 
 The same, 3-carpclled. 230. The free central placenta of Primula. 231. A 1-celled ovary with basal 
 placenta. 232. 2-carpclIed, 1-celIed ovary of Ubolaria, the placentae extended to completely line the 
 wall. 
 
 Modifications of the Placenta. — Some further modifications of the 
 placenta require our consideration. The free central placenta has 
 been considered. Such a placenta frequently becomes partly aborted 
 by the gradual (lisai)])earaiice of its upper portion. 
 
 Basal and Apical Placentae. — Tliis process may continue until the 
 placenta is reduced to a trace at the base (Fig. 231). In other cases it 
 will be reduced to a trace at the apex (Figs. 235 and 237). Basal or 
 apical placentae may be Centric or Fccentric. Modifications of these 
 processes may result in restricting the placenta to any intermediate 
 point. Upon the other hand, such a j)lacenta may become enlarged and 
 fleshy. Similar changes may occur in the j)arietal placenta. It may 
 become reduced to a mere point pre.ser\e(l at the apex, base, or inter- 
 mediate portion. In the watermelon it becomes enormously enlarged. 
 
78 THE GYNAECIUM 
 
 filling the entire cavity with a fleshy, edible mass. In the Obolaria 
 (Fig. 232) it is laterally expanded to form a more or less complete false 
 lining to the ovarian cavity. In this position it may remain free or 
 become coherent, so that, as in this case, the entire face of the ovary 
 may appear to be ovuliferous. By a subsequent obliteration of a portion 
 of such an expanded placenta, the remaining portion may be seen to 
 assume an abnormal position, being occasionally confined to the midrib 
 itself. 
 
 Ovules. — Xumbcr of Ovules. — As has already been pointed out, the 
 number of ovules is extremely variable and the proportion of them which 
 become fertilized is little less so. 
 
 Position of Ovules. — The position of the ovules is to a great extent 
 determined by the nature of the placenta, as has already been explained. 
 It calls for a number of distinctive terms. The two rows of ovules 
 produced by the two carpellary margins do not always appear distinct, 
 but may be reduced, before or after fertilization, to one. 
 
 Series of Ovules. — A vertical row of ovules is called a series, and ovules 
 are thus defined as being One-serialled, Two-serialled (Fig. 219), etc. 
 When there are many series, so that the number is not readily made out, 
 we simply say that they are Many-serialled (Fig. 227). 
 
 Collateral Ovules. — Ovules placed side by side (Fig. 219) are called 
 Collateral. 
 
 Crowded Ovules. — Sometimes no definite series can be made out, 
 owing to the crowding of many ovules into a small space, as in Obolaria 
 (Fig. 232). They are then said to be Crowded. 
 
 Divergence of Ovules. — Collateral ovules, and, indeed, any ovules 
 standing together and deviating from a straight line, have a tendency 
 to turn their foramina away from one another. 
 
 Direction of Omdes. — As to the directions, in relation to the ovary, 
 which ovules assume, they are Erect (Fig. 233) when standing erect 
 from the base; Suspended (Figs. 235 and 237) when occupying an 
 exactly opposite position ; Horizontal (Fig. 234) when taking a direction 
 at right angles to the axis of the ovary; Ascending (Fig. 238) when 
 directed obliquely upward from some point intermediate between base 
 and apex; and Pendulous (Fig. 239) when directed obliquely downward 
 from such a point. When starting as an ascending ovule and afterward 
 drooping (Fig. 236) an ovule is Resupinate, or when as in Fig. 240, 
 Recurved-pendulous. 
 
 Obscuring of the Position. — An ovule may have its direction obscured 
 by peculiarities of attachment. Thus, in Loxoijterygium (Fig. 178), 
 
STRUCrURE AND PARTS OF THE OVULE 79 
 
 the real base becomes, l)y extreme oblicjiiity, ai)i)arently lateral and 
 causes an erect ovule to be ai)i)arently ascending. That of Anemone 
 is suspended, but owing to the same condition a|)])arently only jjcndu- 
 lous. The terms erect and suspended are after all only relative, as we 
 can ne\'er be sure that an ()\iile wliich a])pears in sucli i)osition is really 
 the uppermost or lowermost of its series. \'(ry often others which 
 would have been in reality the basal or apical lia\e become aborted, 
 as in the last case illustrated. 
 
 A merely recurved ovule is not to be mistaken for an anatropous 
 ovule. The latter, as will now be explained, has the contiguous portion 
 of the funicle adherent as a raphe, which comes away with the seed 
 at maturit\'. 
 
 Fig. 233. Erect ovule of Symmeria. 234. Horizontal ovule of Paullinia. 235. Pendulous ovule of 
 Guaiacum. 236. Resupinate ovule of Euonymus. 237. Suspended ovule of Drymicarpus. 238. As- 
 cending ovule of Euonymus. 239. Pendulous ovules. 240. Recurved pendulous ovule of Drunnichia. 
 
 Structure and Parts of the Ovule.— The recognized varieties of ovules 
 are based upon cxtenial structure, which will here be briefly considered. 
 The details of their inner structure will be considered in our cliajjter on 
 Fertilization. 
 
 Body and /'/////Vv////.v.- The ovule consists of a Body (Fig. iMO, a) 
 and a Funiculus or Stem (h). Named in the order of time in which they 
 are develoi)ed, the i)arts of the body are as follows: 
 
 Xucelln.s and Coals. — The Nucelius, or central i)ortion (Figs. 241 to 
 244, /(), containing the parts essential to reproduction, and two coats, 
 the Primine or inner (/,•) and Secundine or outer (.v). Certain i)arts of 
 these, or jjoints upon them, also have distinctive names. 
 
 The Mirropiile. — The more or less circular opening (///) left at the 
 apex by the failure of the coats to comi)lctcIy inclose the nucclhis is 
 the I'^oraincii. 
 
80 
 
 THE GYNAECIUM 
 
 The Chalaza. — The structurally opposite end of the body, or the 
 point where nucellus, coats, and apex of funiculus separate from one 
 another (c), is the Chalaza. 
 
 The Raphe. — If the body become inverted upon its funiculus, 
 either partly (Fig. 24.':)) or wholly (Fig. 242), the portion of the funiculus 
 against which it lies (r) will become adnate to it, and is known as the 
 Raphe. The portion of the funiculus remaining free (/) is then specific- 
 ally known as the funiculus. When hereafter in this work the last 
 term is used it will be understood as applying to this free portion. It 
 is thus seen that the raphe is limited at its distal end by the chalaza; 
 but separation of this seed at maturity cannot take place at this point, 
 owing to the adnation of the raphe, as it would do if no such adnation 
 existed. 
 
 Fig. 241. Atropous or orthotropous ovule; /, funiculus; c, chalaza; n, nucellus; k, primine; s, 
 secundine; m, micropyle; em, embryo-sac. 242. Anatropous ovule; h, hilum; r, raphe; other let- 
 tering the same. 243. Amphitropous ovule. 244. Campylotropous ovule. 
 
 The Hilum. — Separation in such case must take place at the point 
 where raphe and funiculus join; hence the Hilum, as such point of 
 separation is called, may be variously situated, and need not coincide 
 with the chalaza. In Fig. 241 it is at the chalaza, in Fig. 242 at the 
 opposite end Qi), while in Fig. 243 (li) it is about half-way between. 
 The parts here enumerated are not always conspicuous and may be 
 easily overlooked by the beginner: 
 
 Forms of Ovules. — The nucellus is the essential part of the ovule, which 
 in some cases consists of nothing else, and e\e\\ this may be reduced to 
 its lowest es.sential elements. An ovule without either coat is Naked 
 or Achlamydeous; with only primine it is Monochlamydeous, and with 
 both it is Dichlamydeous. An ovule without funiculus, and the same 
 is true of any organ not borne upon a stem, is Sessile. The form of the 
 funiculus, as well as its direction, always calls for inspection. It may 
 be very short and broad (Fig. 241), or elongated and slender (Fig. 240), 
 and the latter form may be either straight or variously curved. 
 
FORMS OF OVULES 81 
 
 The Anatropous Ociilc. — An anatropous ovule (Fig. 242) is one tlie 
 body of which is completely inverted. The raphe runs its entire length 
 and the micropyle is brought close to the hiluni, while the chalaza is 
 at the opposite end. 
 
 TJw Amphitropous Oeule. — An amphitro])ous ()vule (Fig. 243) is one 
 which is i)artly inverted, occupying a position more or less at right 
 angles with its funiculus. Its raphe runs only part of its length, and the 
 hilum is at some point intermediate between the chalaza and micro- 
 pyle, which are at opposite ends. 
 
 The CampyJotropom Omde. — A campylotropous ovule (Fig, 244) 
 is one which need not be at all inverted, but the body of which is 
 doubled over so as to bring the micropyle down near the chalaza. It 
 has, of course, no raphe, and the hilum and chalaza are one. It is very 
 difficult to distinguish this form from an anatropous ovule with a very 
 broad raphe. 
 
 The Atropous or Orthotropoiis Omde. — This (Fig. 241) is an ovule 
 which is neither doubled nor turned, the body being straight and erect 
 upon the funiculus, and having no raphe, the hilum and chalaza at 
 one, and the micropyle at the opposite end. 
 
 Before proceeding to the subject of pollination and fertilization and 
 the changes in the several parts of the flower consequent thereon, we 
 must consider in detail the torus and its modifications. 
 
CHAPTER VII 
 
 THE TORUS 
 
 Review. — The fundamental principles of anthology are based upon 
 the nature of the torus as a modified branch. We have already con- 
 sidered the evidences of this fact depending upon its position and the 
 relative positions of the parts developing upon it. We shall now con- 
 sider some which depend upon its modifications. These are in part 
 permanent and typical and in part exceptional and abnormal. 
 
 Elongation of the Intemodes. — Among the latter we note that in those 
 frequent cases in which the parts of flowers revert to the leaf condition, 
 the torus often elongates, separating the floral series exactly as whorls 
 or spirals of leaves are separated by the internodes upon a branch. At 
 other times, the torus will be continued beyond the apex or center of 
 the flower in the form of a leafy branch. Occasionally one of the sepals 
 will be found at its proper radial point, but vertically distant from the 
 rest of the calyx, a portion of the flower stem intervening. 
 
 The Anthophore. — A similar condition, but affecting an entire series, 
 normally characterizes certain species, or groups of species. The 
 elongation may affect any internode or internodes. When (Fig. 246, a) 
 it is between calyx and corolla it is called an Anthophore. Sometimes, 
 as in Viscaria (Fig. 248), the anthophore may be very slight, so as to 
 escape detection until a longitudinal section reveals its presence. 
 
 The Gonophore. — A similar elongated portion between corolla and 
 androecium is a Gonophore (Fig. 249, a). 
 
 The Gynophore. — One between androecium and gynoecium (Fig. 249, 
 b, and Fig. 252, a) is a Gynophore. A thecaphore (Fig. 9) often resembles 
 a gynophore and may be mistaken for it. The point of articulation and 
 separation at maturity will determine whether the stalk is a portion of 
 the ovary (thecaphore) or of the torus (gynophore) . 
 
 The Carpophore.— A slender extension of the torus upward among the 
 carpels, which are attached to it, constitutes the Carpophore, as in 
 Erodium (Fig. 245). The presence of a carpophore is characteristic of 
 plants in the Umbelliferae (P'ig. 247). 
 
 The Gynobase. — In the Boraginaceae the carpophore is frequently 
 reduced to a pyramidal or conical form, or is shortened or laterally 
 
/''O/i'il/.S OF THE DISK 
 
 83 
 
 expanded until il is iiicrcly convex or even ])l;me. To all such modi- 
 fications the term (lyiiohasc is ajjplicd. Jn this con(htion it may 
 become liollowed ont at the insertion of the carpels, as in borage (Fig. 
 250). In all forms of the gynol)ase it is important to note the point 
 of attachment of the divisions of the ovary and the scars wliich the 
 latter lea\e upon removal. 
 
 Fig. 245. Pistils of Erorliiim siiriiifziiiK away from the carpopliore (a). 24(5. l-'lower of Lychnis, 
 showing anthophore at a. 247. Carpels of parsnip attached at summit of carpophore. 248. Flower of 
 Viscaria with obscure anthophore. 249. Flower of Maerna, a gonophore at a, a gynophorc at h. 
 250. Gynobase of Borago. 251. Numerous pistils of Magnolia, imbricated upon a carpophore. 252. 
 Greatly enlarged gynophore of Xelumbium. 253. Ring-shaped disk (a) of Halpichroa adnate to calyx. 
 254. Epigynous disk (a) of Coussarea. 
 
 Abbreviation of the Internodes. — The al)o\e considerations refer to 
 elongations of internodes of the torus. The condition of adnation of 
 floral parts may, upon the other hand, be usually looked upon as one 
 in which the normally very short internodes of the torus are still further 
 shortened, so as to bring the parts into most intimate connection. 
 
 Lateral Expansion of the Internodes.- lii>tca(l of nudcrgoing a uumt 
 elongation of its internodes, the torus may l)c latcrall>- exi)anded at any 
 or all points, with or without elongation, and in imuiincrable forms. 
 
 The Disk. — An exi)ansion or appendage of this kind, although the 
 term may be properly regarded as including all forms of enlargement 
 or extension of the torus, is called a Disk. 
 
 Forms of the Disk. — The sim])lest form is, ])crliaps, that seen in the 
 blackberry, a hemisphere, with the j)istils arranged ui)on its surface 
 
84 
 
 THE TORUS 
 
 (Fig. 305), although most of the enlargement here seen, as in the next, 
 is the accrescence of fructification. The disk of the strawberry (Fig. 
 304) is similar, but its pistils are partly immersed. In the rose, a 
 related plant (Figs. 59 and GO), the form is modified by the elevation of 
 the margins, instead of the center, so that a cup-shaped disk is formed, 
 the pistils attached over its inner surface. In the cherry (Fig. 58) the 
 disk is thin and lines the calyx-tube, the pistil being free. In the apple 
 there is a similar disk lining the calyx-tube, and it, at maturity, is 
 thick, fleshy, and edible, and encloses the five pistils. In the Magnolia 
 (Fig. 251) the torus is vertically much elongated and at the same time 
 
 Fig. 260. Saucer-shaped disk of Pseudima. 261. Similar disk of Allophyhts, but irregular and uni- 
 lateral. 262. Disk with two lobes coherent. 263. Cupulate, sinuate-margined disk of Hippocratea. 
 264. Disk of Xanthoceras, of five distinct horns. 265. Cupulate disk with lobed margin. 266. 
 Campanulate disk of Santalum, adnata to calyx-tube. 
 
 much thickened, the pistils adnate along its surface. In the Nelumbo, 
 the torus (Fig. 252) is enlarged into a top-shaped or Turbinate body, 
 with the pistils embedded in the flat upper surface. Instead of thus 
 occupying a hj-pogynous position, the disk may be projected between 
 any two of the circles, and it may be wholly or partly adnate to either 
 (Fig. 266, a), or to both of them, or it may be entirely free. When 
 adnate to both circles it is plain that it becomes responsible for the 
 existing adnation between the latter. It may then exist only at the 
 base, or it may entirely fill up the interspace between the parts and even 
 become epigynous, so that the ovary is immersed in it or buried under- 
 neath it (Fig. 254, a) . The adnate disk may be shorter or longer than 
 
FORMS OF THE DISK 85 
 
 the circle to wliidi it is adnate. The simplest manifestation of tlie disk 
 is that of a mere swelling or ring (Fig. 200) at the summit of the torus; 
 its greatest that in which it becomes an elongated cu]) or tube. Either 
 form may be entire or more or less divided, from that Avith a mere sinu- 
 ately lobed margin (Fig. 263) through the toothed and lobed (Fig. 2G5) 
 to that consisting of entirely separate divisions (Fig. 204). It may be 
 regular, as in the above illustrations, or very irregular (Fig. 2()1), and 
 cohesion may exist between some of its divisions while the others are 
 distinct (Fig. 262). The lower portion may be adherent while the 
 upper, lobed or entire, is free (Fig. 260). It may be itself appendaged, 
 and it may or may not be glandular in nature. Finally, we note that 
 the disk may be double, its two circles occupying different internodes 
 of the torus. The texture of the disk is commonly thicker than that 
 of the other parts, but it may be laminar. It is, therefore, sometimes 
 easy to mistake a disk for a corolla, aborted stamen-circle, or crown. 
 In all its peculiarities above described, and in the number, size, and form 
 of its divisions and appendages, the disk is characteristic and of the 
 greatest value in classification, either generic, as in the Gesneriaceae, or 
 specific, as in Eschscholtzia. 
 
CHAPTEPv VIII 
 
 DISSECTION AND ANALYSIS OF THE FLOWER 
 
 Apparatus Required; Microscopes. — For the thorough and convenient 
 examination of floral structure, it is desirable to employ both the 
 compound and the simple microscope, and it is better to use two forms 
 of the latter. The compound microscope for ordinary use should have 
 a focus of about li inches, and it should be provided with a strong 
 illumination for viewing opaque objects. The simple microscopes used 
 should be a dissecting microscope, having a magnifying power of 
 some 20 to 30 diameters and an ordinary jeweller's loup. It must not 
 be assumed, however, that all of these instruments, useful as they are, 
 are essential to the work. Excellent work in all directions can be 
 performed by the use of a strong loup alone, especially if it be held in 
 the eye or attached by means of a flat steel wire passing around the 
 head or inserted into a spectacle frame, so that both hands may be 
 free for the work of dissection. 
 
 Other Apparatus. — ^The other apparatus required is a pair of pointed 
 forceps, a pair of stout needles inserted into thick wooden handles, and 
 a dissecting knife. 
 
 Regular Order of Procedure. — ^It is well for the student in the examina- 
 tion of flowers to accustom himself to a definite order of procedure, as 
 the numerous points to be noted are thus far less likely to be forgotten 
 or overlooked than when considered in a disorderly manner. It is 
 furthermore highly desirable that the characters observed should be 
 written down in systematic sequence before the book is referred to. 
 The order of procedure is from without inward, or in other words, from 
 below upward. The anthotaxy should first be carefully examined and 
 the position of the flower with reference to others in the cluster noted, 
 as well as its position upon the stem and the direction in which it faces. 
 The position when in l)ud should be compared with that when in flower. 
 When flowers are aggregated in ,close clusters surrounded by involucres, 
 all the characters of the latter as a whole and of the bracts of which 
 they are composed, must be noted precisely the same as though we were 
 studying the calyx of a single flower. The receptacle upon which the 
 flowers are borne within the involucre must also be thoroughly examined 
 as to its size, form, and surface and the ])resence of bracts or scales 
 interposed among the flowers. 
 
liFJUl.Mi OUDKU OF /'!,•( K •!■: I )Uh-J'J 87 
 
 ("oiniii.u' next to the study of ;i single flower, it iiiii.st first he cxaiuiiicd 
 in the hud coiuhtioii and its ])r;K'floration dctcnniiuvh In inakini,' 
 this ohservation, it is necessary that the ])arts, first of the calyx and 
 afterward of the corolla, should one \)y one he carefully separated with 
 needle or forcei)s, heginninfj; at the apex and drawing backward and 
 downward, the lines of separation being closely scrutinized while the 
 separation is taking place. The fully expanded flower is next examined. 
 The presence of both calyx and corolla, or of one or neither, is first in 
 order, 'i'lie regularity or irregularity of the several circles can be 
 determined at a glance, as well as their numerical symmetry. The 
 same ra])id glance will determine the relative sizes of the different 
 circles, the exsertion or inclusion of the essential organs, the general 
 form of the flower, and color, surface, and positions of the parts. All 
 the above observations may be regarded as superficial. It then becomes 
 necessary to examine into those details which require dissection. 
 
 The sepals should first be turned back and examined as to their 
 cohesion at the base, when this is so slight as to be inappreciable upon 
 superficial examination. At the same time their adhesion to the inner 
 series, especially to the ovary, can usually be determined. The corolla 
 should then be carefully pulled oft' to ascertain whether any degree of 
 cohesion exists among its petals and also to determine the relation of the 
 stamensto it. Thestamens are next to be removed, and this is preferably- 
 done by pushing against them at the base from a lateral direction with 
 a blunt instrument, so as to ascertain whether they exhibit a tendency 
 to cohere in groups. The superficial characters of the g>'naecium also 
 can now be readily ascertained. The presence of a disk interposed 
 between gynaecium and calyx must then be searched for and its char- 
 acters determined, as in the case of the other circles. It has already 
 been explained that the disk may be easily overlooked through its 
 adhesion to calyx or corolla or both. Occasionally it will be overlooked 
 because it exists in the form of a granular or powdery mass. 
 
 The general observations thus determined should next be verified 
 and more accurately made by making a vertical incision through one 
 side of the calyx and disk, if the latter be i)resent, and carefully remov- 
 ing them. The body thus renio\-e(l may then be flattened out and the 
 relations of all its parts be fully seen. If, after the initial incision has 
 been made, it be ascertained that adhesion exists l)etween the calyx 
 and gynaecium, so that the former is not readily removed, the incision 
 nmst then be carried entirely through the flower and the latter sei)a rated 
 into two a|)proximately e(|ual portions. In either case search for 
 nectaries or other ai)penilages nnist next \)v made. This subject has 
 
88 DISSECTION AND ANALYSIS OF THE FLOWER 
 
 been so thoroughly considered, that it need not be again taken up except 
 to say that glands, which are frequently metamorphosed stamens or 
 appendages to the several parts, must not be mistaken for a disk. With 
 the flower in this position it may also easily be seen whether the parts 
 are cyclical, and if so the number of circles may be determined. If 
 duplication has occurred, its origin in chorisis or metamorphosis is 
 readily determined, while if sujipression has occurred it can readily 
 be referred to the respective circle. 
 
 The relation of the parts to one another having been thus determined, 
 each of them must next be studied individually. The shape and texture, 
 and the division into parts, with the details of any existing appendages, 
 will be sought separately in sepal, petal, and stamen and in filament 
 and anther separately. In the examination of the stamen, it is essen- 
 tial that it be examined separately in direct lateral, ventral, and dorsal 
 views, as only thus can the true relations of its parts become known. 
 The form of attachment of anther to filament and the point of junction 
 between filament and connective are next in order, as well as the form 
 of dehiscence of the thecae and especially the position and direction 
 assumed by the sutures, pores, or valves of the latter. The chief diffi- 
 culty in the examination of the stamens will be in determining the part 
 upon which any existing appendages originate. The position which 
 such an appendage occupies is frequently quite misleading as to the 
 nature of its origin, and it must be carefully moved about with the 
 points of the needles, great care being taken that no delicate attachment 
 is severed, before it can be definitely ascertained whether an appendage 
 originates from filament, connective, or theca. 
 
 It is, moreover, not rarely the case that the characters of appendage 
 and anther are so concealed or even substituted that the one may be 
 mistaken for the other. The examination of the stamen is not com- 
 plete until the characters of the pollen, as to its being granular or 
 collected into pollinia, the nature and characters of the latter, and even 
 the characteristics of the individual pollen-grain, have been determined 
 by the aid, chiefly, of the compound microscope. 
 
 The gynaecium, still in position upon the torus, must next be studied 
 as to its relations to the latter and its composition of united carpels 
 or separate pistils. If of separate pistils, they must be separately 
 removed from the torus, great care being taken not to mutilate the 
 latter, and their number and regularity must be determined. If 
 regular, the detailed examination of one of them is sufficient, but if 
 irregular, one of each form must be separately studied. 
 
 The external characters of the pistil present no difficulty for exami- 
 
PREPARATION OF DRIED SPECIMENS FOR EXAMINATION 89 
 
 nation, bnt the examination of their strueture and contents constitutes 
 perhaps the most (hfHeult i)art of floral dissection. It is very desirable 
 that the stigmas be subjected to examination with the compound 
 microscope, as the character of its surface and the form and distril)ution 
 of the stigmatic surface proper upon the style and u]nm the body, 
 which may at first sight be regarded as the stigma, is frequently a matter 
 of the utmost importance. The dissecting knife must now be used for 
 dividing the ovary into a number of transverse sections, which must 
 then be separately viewed by transmitted light. This examination will 
 determine the number of cells and their completion by the continuation 
 of the septa from top to bottom. It will also in most cases be sufficient 
 to enable us to determine the number of ovules and the position and 
 character of the placentae. All these points should, however, be veri- 
 fied by the subsequent examination of vertical or longitudinal sections. 
 Finally the ovules must be removed and their form and structure 
 determined by the aid of a compound microscope. 
 
 It may be pointed out in conclusion that the examination of a single 
 flower is not always sufficient to determine the structural characters. 
 Dimorphism or dichogamy, unrecognized by the student, may lead to 
 the most false conclusions. 
 
 The student should also be cautioned against the temptation to 
 examine the partially or wholly matured fruit with the idea that he 
 can thus more easily determine the characters of the gynaecium. As 
 will be shown later, great changes frequently occur in the structure 
 of the pistil during fructification. 
 
 Preparation of Dried Specimens for Examination.— The oi-dcr of exam- 
 ination is the same whether a fresh or a dried flower be under considera- 
 tion. In the case of the latter, however, it is necessary that it be first 
 thoroughly softened by immersion in water. For this purj)ose it may 
 be left in warm water all night or for a longer period, or as is usually 
 more convenient, it may be boiled for from one to five minutes, accord- 
 ing to its texture, in a s])oon or porcelain dish held in the flame of an 
 alcohol lamj). Considerable exi)erience is required to know just how 
 long to subject it to the action of the hot water. If too quickly removed, 
 the tissues will be found stifi" and resistant, while if it be boiled too 
 long, they will become so thoronulily linij) as to lose all trace of their 
 natural i)()siti<)n. If the jmxcss i> jx rfcctl^- ])(M-formed, the flower may 
 be thrown \i\)(n\ a blotter and after the excess of moisture has been thus 
 removed, will be found very much in the original growing condition 
 and yielding easily to manipulation. 
 
CHAPTER IX 
 
 POLLINATION AND FERTILIZATION 
 
 Review. — It has been stated that the essential female element of 
 reproduction in the flower is produced in the nucellus of the ovule, the 
 male by the germination of the pollen-grain. It has also been shown 
 that these two elements are produced separately, and in most cases 
 remotely, from one another, and that some means must exist for bring- 
 ing them together in order that fertilization may be effected. 
 
 POLLINATION 
 
 In those plants (Gymnosperms, P^igs. 174 and 175) in which no 
 stigma exists, this is accomplished by immediate contact of the pollen 
 with the ovule, which is exposed for the purpose. In those in which a 
 stigma exists, it is accomplished by the deposit and fixation of the 
 pollen thereupon. To either of these processes the term Pollination 
 is applied. 
 
 Close-pollination and Cross-pollination. — The two elements may 
 proceed from the same flower, in which case the term Self-pollination or 
 Close-pollination is applied, or they may proceed from different flowers, 
 in which case the term Cross-pollination is applied. It will be noted 
 further that there are degrees of crossrpollination, according to whether 
 the elements proceed from flowers upon the same or upon different 
 plants. When the flowers are perfect, it is at least possible in most 
 cases for them to be either close- or cross-pollinated. 
 
 Cross-pollination Beneficial. — In nearly all cases, the reproductive 
 function is strengthened through cross-pollination, which explains 
 the fact that nearly all flowers are constructed so as to facilitate the 
 process, while most of them are so constructed as to incommode, and 
 very many to prevent, close-pollination. In a few cases the flower is 
 constructed so as to prevent cross-pollination. 
 
 Methods of Securing Cross-pollination.- I'lie methods of effecting 
 cross-pollination may be divided into the ordinary and the exceptional. 
 
l'h'()\ISI(>.\S FOR ATTUACTIXa IXSECTS 
 
 !)1 
 
 The latter must he considered iii(hvi(hiall\ . The former are two — 
 namely, throufijh the agency of tlie wind and throufj;h that of insects 
 (or occasionally other animals). 
 
 Anemophilous and Entomophilous Flowers. — Flowers adapted to the 
 former methods are called Anemophilous; those adapted to the latter 
 are called Entomo])hilous. Occasionally the flower is so formed that 
 the movement of the water during rains, or in streams, effects pollina- 
 tion. 
 
 Provisions in Anemophilous Flowers. — The activity of the wind hcing 
 heyond the control of the flower, the adai)tati()n of the structure of an 
 anemophilous flower is limited to securing the benefits of such action 
 when it comes into play. This consists chiefly in (1) a gregarious habit 
 — the growing together in great numbers of individuals of one kind, as in 
 the case of grasses and of most of the forest trees of temperate latitudes; 
 (2) a very abundant j)()llcn ('.]), which is loosely fixed, one method 
 being illustrated by Fig. 2()7, light and easily 
 removed and transported; and (4) the dispo- 
 sition of the ovule of gymnos])erms, and the 
 form and disposition of the stigma and con- 
 nected parts of angiosperms, so as to catch 
 the pollen. All these provisions may be 
 readily seen to affect the process in the case 
 of Pitiiift pal list r is, for example. In this 
 l)laiit the ])()llcn-grains contain several cells, 
 all but one of them empty, thus decreasing 
 
 tlicir specific gravity. They are produced in such great abun- 
 dance that the crop, carried by strong winds, has been known to 
 fall at a great distance as a thick deposit, the so-called "sulphur- 
 showers" of history. The trees are densely massed, to the exclusion 
 of almost all others, and bear innumerable cones (Fig. .SfiO), each 
 consisting of numerous scales, outwardly flaring, and so (lisi)ose<l as 
 to catch many of the j)ollen grains and guide them downward to the 
 little pockets at their bases. 
 
 Provisions in Entomophilous Flowers. In entonioi)hilous (lowers, such 
 provisions as aboNc described for the utilization of the i)()llen-carr\ing 
 forces, nuist be preceded by others of a dilVereiit nature, eal(ulate(j to 
 first set in motion and attract these forces. 
 
 Provisions for Attracting Insects. l*i-()\isi(»Ms for atti-acting external 
 agents are found chiefly in the form, coloration, and size of the Hower 
 or of one or more of its i)arts, the ])roduction of fragrant and nutritive 
 
 Fig. 2()7 
 
 Anemophilous flower of 
 a grass. 
 
92 
 
 POLLINATION AND FERTILIZATION 
 
 secretions and the exercise of these influences at the most opportune 
 times. 
 
 Form. — The form of the flower is efficient when it resembles a form 
 attractive to an insect the visit of which is desirable, or when it is 
 one well calculated to display effectively the coloration; and it is not 
 impossible that certain forms, like certain colors, are attractive jmv se. 
 The forms of nectar-bearing flowers are, moreover, in most cases, such 
 as to facilitate the collection of the food by the visiting insect, or, 
 when otherwise, to eft'ect special objects to be considered farther on. 
 For example, it is usually a peripheral or central position of the nectaries 
 
 which respectively determine the ex- 
 trorse or introrse dehiscence of the 
 anthers. 
 
 Color. — Coloration also may be 
 attractive, through its simulation of 
 an insect or merely by its serving 
 to make known to the insect the 
 presence or position of the flower 
 concerned — as a white, light-colored, 
 or lustrous flower, in attracting in- 
 sects which fly only when there is 
 little light. 
 
 Function of Neutral Floivers.— 
 Flowers are frequently modified in 
 size so as to effect these results, and 
 this modification is often secured at the expense of their own sexual 
 functions. Fig. 268 illustrates a cluster of Viburmnn flowers, the 
 marginal being large and light-colored and admirably adapted to 
 attract insects, but destitute of perfect reproductive parts. This 
 tendency to produce upon the same plant flowers of two kinds, the 
 one for display, the other for rei)roduction, is widely manifested. In 
 the Einphegus, the flowers produced respectively upon the lower and 
 upper portions of the stem exhibit this difference. In such heads of 
 flowers as the Daisy, the showy marginal flowers are very frequently 
 sterile, even though pistillate, and attract insects which then poIHnate 
 the inconspicuous central flowers. 
 
 Odor. — The odors of flowers, while frequently offensive to the human 
 sense, are supposed to be attractive in most cases to the insects whose 
 visits favor their pollination. They result from the evaporation of 
 volatile oils. The glands by which these oils are excreted and in which 
 
 Fig. 208. Inflorescence of Viburnum with 
 neutral marginal flowers. 
 
POLLINATION BY BIRDS 93 
 
 they are stored may be distributed through the tissues of all or certain 
 of the floral parts, or their presence may be restricted to the special 
 appendages described below. 
 
 Nectar and Nectaries. — The nutritive substances other than pollen 
 to be consumed by tlio visiting insect, known as Nectars, are produced 
 by certain special glands and are stored in or upon contiguous receptacles 
 called Nectaries. The presence of these nectaries is commonly responsi- 
 ble for the outgrowth of the appendages to which they are often attached 
 (Figs. G3 and 05). At other times a part of the flower not conspicuously 
 modified produces and holds the nectar. 
 
 Time of Activity. — The influences here described are in almost all 
 cases exerted at certain times which are especially favorable for securing 
 the desired results. In speaking of the perigone, it has been shown 
 that the duration of flowers varies greatly. It may be further stated 
 that those which perish quickly mature and ex])and at the particular 
 time of day when pollination is most likely to occur. Those which last 
 for several days enjoy a daily resting period and another period of 
 greatest activity, the details of which vary in different species or classes. 
 Commonly, the perigone becomes more or less folded or closed during 
 this resting period, its form and coloration less conspicuous, the exhala- 
 tion of odors entirely suspended or greatly restricted, and access to the 
 nectar prevented altogether. At the same time that its functions are 
 thus inactive, its position is such as to afford it protection of various 
 kinds from dangers which are especially imminent during the hours in 
 which it rests. 
 
 Sleep of the Flower. — This condition of inactivity or rest is commonly 
 spoken of as the sleep of the flower. It occurs at such a period of the 
 day as finds the agencies specially adapted to pollination in its case 
 themselves enjoying their rest. As these again become active, the 
 flower "awakens" and all the conditions above noted are reversed, or 
 at least such of them as affect the flower in question. # 
 
 Diurnal and Nocturnal Flowers. — Flowers in which this active period 
 occurs during the day, whether they endure for but one day or longer, 
 are called Diurnal; those in which it occurs at night are called Nocturnal. 
 Besides the regular daily resting period, a great many flowers, by virtue 
 of special sensitiveness, possess the power of assuming such a condition 
 on special occasions when the conditions call for it. 
 
 Pollination by Birds. — Humming-birds, as well as insects, are active 
 participators in the operations above recorded. Their operations 
 in promoting cross-pollination in the Cinchona group have been largely 
 
94 POLLINATION AND FERTILIZATION 
 
 responsible for some of the most far-reaching economic conditions and 
 results in the history of the drug trade. In exceptional instances, still 
 other animals take ])art in this work. 
 
 Participation by other Parts than the Flower.^ — It may be remarked in 
 passing that these characters, like some of those which follow, are not 
 restricted to the flower itself. Very frequently other portions of the 
 plant adjacent to the flower will be expanded, brightly colored, and 
 developed into special forms, while the odor of some flowers, due to 
 the presence of glandular tissues, is shared by the foliage and other 
 herbaceous portions, as in the lavender. Well-formed, large glands are 
 present in the axils of the primary veins of the leaves of some species 
 of Cinchona, although the precise function which they perform is by 
 no means clearly established. 
 
 Provisions for Utilizing Insect-visits. — The special contri^'ances for 
 utilizing insect-visits in eft'ecting pollination are far more elaborate 
 and varied than those for inducing them, which we have already 
 considered, and our consideration of them cannot be extended beyond 
 what is necessary to indicate their general nature and classification, 
 and to serve as a key in understanding the complicated modifications 
 which we have observed the typical flower to undergo. Usually the 
 effects extend in two directions — (a) toward excluding the pollen from 
 access to the stigma of its own flower, and (6) toward securing its 
 access to that of another. 
 
 Dichogamy. — One of the most frequent methods of securing the 
 former result is the maturing of the androecium and gynaecium at 
 different times. This method is called Dichogamy. 
 
 Proterogyny and Proterandry.^ — By it the ovules of a flower are already 
 fertilized before the mature pollen of that flower escapes from its thecae 
 (Proterogyny), or else the pollen is matured and utilized before the 
 stigmas of that flower are prepared for its reception (Proterandry). 
 
 Proterandry is well illustrated by Figs. 269 and 270. The former 
 illustrates the anthers erect with their pollen ready for removal, while 
 the stigmas are yet immature. The visit of an insect to such a flower 
 cannot aft'ect the stigma, but will result in the transportation of the 
 pollen to another flower, perhaps in the condition represented by Fig. 
 270. Here it will be received upon an active stigma, the anthers having 
 already perished and dropped beneath the margin of the corolla. 
 
 Figs. 271 and 272 illustrate proterandry assisted by a special mechan- 
 ical device. The former represents a flower with closely syngenesious 
 and introrselv dehiscent anthers. 
 
PROrEIiOaYNY AND PROTERAXDRY 
 
 95 
 
 Its style is two-cleft, the stigmas existing iipou the inner faces of the 
 branches, their outer faces being clothed with stifi" hairs pointing 
 nj)w;ir(l. It is obvious that until these style-branches separate, polli- 
 nation cannot take place. Before such separation occurs, the tip of the 
 style is, by elongation, slowly forced u]) through the tube of the anthers. 
 The anthers, with their contained pollen, are mature, and the pollen is, 
 by the stifi' hairs upon the backs of the style-branches, torn out from 
 its receptacles and exposed to such agencies of trans])()rtation as may 
 be prepared to act upon it. Cases are even known in which the tearing 
 out of the ])()l]cn in tliis way is cllVctcd by a spasmodic shortening 
 
 
 Fig. 200. nichogamous flower of Milchrlla in first stage. 270. The same, in second stage. 271. 
 Dicliogamous flower of Vernoriia in first stage. 272. Style of same in second stage. 
 
 of the stamens ni)on the instant of contact by a visiting insect, the 
 pollen being by the same process at once discharged iii)on tiie Ixidy of the 
 latter. After the removal of the j)ollcn, or after the (k-ath of such 
 grains as fail to be removed, the style-l)ranches .separate (Fig. '272) in 
 readiness to receive the pollen brought from .some other flower. This 
 method, or some modification of it. is very common among the Co7u- 
 positae, and illu.strates how the study of pollination serves to explain 
 many modifications of flower-structure otherwi.se inex])lieable, and why 
 the possession of tlic latter is reganh'd by the biologist as indicating a 
 higher stage of de\clo])ineiit. 
 
 Dichogamy is very conmion among perfect aiieni()i)liil()us flowers, 
 
96 POLLINATION AND FERTILIZATION 
 
 where self-pollination would otherwise commonly result, and it may 
 be assumed to have been the first step toward the uni-sexual state, so 
 common among flowers of that class. Careful notice should be taken 
 of the fact that in dichogamy the retarded state observed in androecium 
 or gynaecium is but temporary, and that the finally develc^ed form is 
 the same, whether the flower be proterandrous or proterogynous. 
 
 Dimorphism. — A far more profound modification is that in which there 
 is a permanent change in the androecium (Fig. 273) of one flower and 
 a similar change in the gynaecium (Fig. 274) of another, by which a 
 similar result is obtained to that proceeding from dichogamy. Such 
 a provision constitutes Dimorphism. By a modification of it, a third 
 form of flower, intermediate between the other two, is produced, con- 
 stituting Trimorphism. The explanation of the case of dimorphism 
 here exhibited is as follows : An insect visiting flower No. 1 and thrusting 
 
 his proboscis deeply into the corolla- 
 tube in search of nectar, brings his 
 body into contact with the stamens, 
 and pollen is deposited upon it. The 
 next flower visited may be one like 
 2/^4^ No. 2, having a long style. The por- 
 tion of the body which is now covered 
 with pollen will then be brought into 
 
 Fig. 273. Long-styled form of dimorphous COUtact with the StigUia, UpOH wllich 
 aoy^er of Houstonia. 274. The same, long- ^j^^ jj^^^ j^ dcpOsitcd. At the SamC 
 
 staminate form. ^ 
 
 time a different part of the body is 
 being laden with pollen from the short stamens of flower No. 2, to be 
 deposited upon the short pistil of still another flower, similar to No. 1. 
 If perchance two flowers of the same form are visited in succession, the 
 result is that an additional deposit of pollen is secured, or at most a 
 portion of the pollen already being carried is left upon the stamens of 
 the visited flower. 
 
 As will be seen by a consideration of typical examples of each, dimor- 
 phism is more intimately connected with the transferring of the pollen 
 than is dichogamy, though the latter is rarely without some special 
 provision for thus supplementing the effect which it produces in 
 excluding the pollen from the stigma of its own flower. 
 
 In conclusion, it may be said that even if, by some failure in the 
 provision here described, the flower should become self-pollinated, we 
 have excellent reasons for believing that pollen from a different flower 
 which might be deposited at the same time would find an advantage 
 
CLEISTOGAMY 97 
 
 accorded to it by whicli it would he enabled to first reach and fertilize 
 the ovules. 
 
 Coercion of Insect by Special Forms. — The assuming of a form con- 
 venient for the visiting insect, to which reference has been made, is 
 very frequently interfered Math for the purpose ' of forcing the insect 
 into such a position as shall favor or compel the removal of the pollen, 
 a labor which is by no means agreeable to it and which it not rarely 
 seeks to avoid, as in the case of the bee, which cuts a hole at the base 
 of some corollas, through which its food may be extracted. 
 
 No better illustration of such coercion of the insect by special form 
 could be selected than that of the Asclepias (Fig. 27G). The nectary is 
 at a, in the bottom of a large slipper-shaped pouch. Into this pouch 
 the insect would naturally thrust its proboscis in the direction of the 
 
 276. 
 
 Fig. 275. Highly magnified papillose stigmatic surface. 276. Vertical section of flower of Asclepias: 
 a, nectary; b, blind pouch; c, horn; d, pollinium; e, glutinous corpuscle of same; /, stigma. 
 
 point b, thus avoiding contact with the pollen. The appendage c, 
 however, cuts off this line of approach, sei)arating the blind pocket b 
 from the nectary a. In order to reach the latter, the insect is now 
 forced to seek an entrance at the ])oint d, his head being thus forced 
 into contact with the pollen at e, which adheres and is carried away to 
 be applied to the stigma/ of the next flower visited. 
 
 In spite of the possibility of thus effecting a rough classification of 
 some of the methods of securing cross-pollination, it is yet true that the 
 great majority of instances are not subject to classification and must be 
 denominated special, or else that they combine some si)e(ial arrange- 
 ments with such general methods as have been described. 
 
 Cleistogamy. — Flowers which are self-fertilized before exi)ansion are 
 Clei.stogamous. Occasionally, fertilization takes i)laee without the 
 removal of the pollen from the anther. 
 7 
 
98 POLLINATION AND FERTILIZATION 
 
 Fixation of the Pollen. — The pollen thus transferred to the stigma 
 must be fixed there in order that fertilization may follow pollination. 
 This process is effected by contrivances little less elaborate, although 
 more minute, than those which have been described. These con- 
 trivances relate in part to peculiarities of the pollen. As regards the 
 stigma, fixation is effected most generally by means of the viscid 
 secretion to which reference has been made, the stigma being essentially 
 glandular in nature. Appendages in the form of hairs, scales, or 
 papillae (Fig. 275) are very common. In some cases the divisions of 
 the stigma are sensitive and close elastically upon the pollen as soon 
 as it is deposited. With the fixation of the pollen upon the stigma, 
 pollination is completed and preparations for fertilization begin. 
 
 FERTILIZATION 
 
 A knowledge of fertilization is of importance to the pharmacognosist 
 only as it throws light upon the characters of the fruit, in which we 
 include the seed as a part. Only the principal facts connected with the 
 subject will, therefore, be here considered. 
 
 Internal Structure of the Ovule. — The gross appearance and parts of 
 the ovule have already been described. Its internal structure is illus- 
 trated in Fig. 277. 
 
 The immediate function of the flower has been seen to be the pro- 
 duction of spores. These spores are to act as reproductive bodies, which, 
 like seeds, they can do only by germinating and growing in a suitable 
 soil. This function of each will now be considered. 
 
 We have seen that the macrosporophyll is the carpel, its macro- 
 sporange the ovary. The macrospore itself is the large centrally 
 located cell of the nucellus, which is to develop into the embryo-sac, e. 
 The natural soil for the germination of this spore is the tissue of the 
 nucellus where it is formed. Its germination takes place immediately 
 and results in the development of the several distinct bodies figured in 
 the illustration. Of these bodies, the oospore or vegetable egg, o, is 
 the ultimate female reproductive element. 
 
 The Gymnospermous Ovule. — The OA'ule of gymnosperms agrees in 
 the possession of an embryo-sac, with several bodies corresponding to 
 the oosphere of angiosperms, but with the other corpuscles not clearly 
 developed. The foramen is secretory, so as to be adapted to acting 
 upon the pollen-grain which it receives, as does the stigma in angio- 
 sperms. 
 
77//'; roLLKX-TUBE 99 
 
 The Female Gametophyte.- As is tlic i)r<)(Iii(t of seod-germination, 
 so is the product of sixuv-uvnuiiiatioii a plant. The plant which results 
 from seed-germination, and wliicli ])r()duces spores, has been called a 
 si)orophyte. That which results from spore-germination, and the 
 ultimate function of which is the production of seed; is called a gameto- 
 ])hyte. Hence the mass contained within the embryo-sac is such a 
 l)lant. the female gamctophyte. It will rest in the state in which we 
 now find it until its oiisphere is acted upon by the male element, which 
 wc ha\e yet to consider, and if such action does not occur, it will die 
 and (lisa])pear. 
 
 Connection between Stigma and Ovule. — Between the ovule thus 
 prepared and the stigma, there is an almost continuous connection 
 through conducting tissue, extending through the body of the stigma, 
 style, and placenta. The extent of this conducting tissue, like that of 
 the stigmatic surface, is usually greater or less according to whether 
 there are more or fewer ovules to be fertilized. 
 
 We have seen that the soil u]K)n which the microspore is intended to 
 germinate is the stigma, in angiosperms, and the foramen of the ovule 
 in gymnosperms. The process of germination is dependent upon the 
 following structural characters: 
 
 Structure of the Microspore.^ The ])()llcn-grain consists of a highly 
 hygroscopic mass of tissue, ])artly vital and ])artly nutritive, the latter 
 of variable composition, surrounded !)>■ a thin, iion-])erforated, highly 
 elastic membrane, the Intine, and this in turn by a thicker, non-elastic 
 covering, the Extine, or "Exine," bearing one or more comi)lete per- 
 forations, very thin ])laces, or otherwise modified ])oints u])on its surface. 
 In exce])tional cases there is instead but a single wall. 
 
 Germination of the Microspore. — The ])rocess of fertilization is illus- 
 trated l)\- Fig. 27s, and the onhiiary jjhciionicna are as follows: The 
 l)ollen grain (a), fixed \i\un\ the stigma of the angiosjierm, or upon the 
 sununit of the o\ule of the gymnos])crni, the hygroscoi)ic contents 
 absorb moisture from the secreting or transuding surface with which 
 it is in contact, the nuiss increases in si/e and distends the intine which 
 surrounds it. Shortly ccll-di\ision of its contents takes place, the com- 
 i)ined changes constituting the germination of the micros]>ore. 
 
 The Pollen-tube.— Through one or more of the ])erforations of tlu> 
 extine already existing, or forcii)ly made )>> this ])ro(ess, ])rotrude 
 prolongations of the pollen contents, still cnxcioped in a |)rocess of the 
 intine. Such a i)roIongation is known as a Pollen-tube {h). 
 
100 
 
 POLLINATION AND FERTILIZATION 
 
 The Male Gametophyte. — A body of this kind, proceeding from the 
 germination of a matured spore, is properly to be regarded, Hke its 
 female homologue, as a plant body. It is to be noted, in passing, that 
 it can be equally well produced by germination upon other surfaces 
 which present the proper conditions. 
 
 Fig. 277. Diagram illustrating structure of ovule: s, synergidae; o, o6sphere; sek, nucleus; e, 
 embryo-sac; g, antipodal cells. 278. Diagram illustrating fertilization: a, pollen-grains on stigma; 
 h, pollen-tubes penetrating stigma and style and entering ovarian cavity, one of them entering the 
 foramen of the ovule at c. 
 
 Following the same course of reasoning as in the case of the female 
 gametophyte, we see that this pollen-tube is the male gametophyte. 
 Its structure is not, or apparently not, even so highly developed as in 
 the case of the other. 
 
 The Male Cell. — At its lower end are one or more little bodies which 
 constitute the male element and which are to fertilize the oosphere 
 which we have already observed within the embryo-sac. This fertil- 
 izing element is the INIale Cell, or Antherozoid. 
 
 In some of the lowest of the flowering plants, and in most of the 
 Cryptogams, this male cell is highly organized, with a specially formed 
 body, is capable of locomotion, and possesses peculiar powers of 
 nutrition. It is comparable with the spermatozoon of animals. 
 
 The Descent of the Pollen-tube. — The male cell or antherozoid is quite 
 as incapable of reproducing by itself as is the oosphere, and its sole 
 function is to act upon the latter, fecundating it. This is accomplished 
 
THE DESCENT OF THE POLLEN-TUBE 101 
 
 by the penetration of the loose celkihir tissue oi tlie stigma, then of tlie 
 style, by the pollen-tube. Nourishment for its growth and movement 
 is afforded partly by the contents of the pollen-mass and partly by 
 absorption from the tissues of the stigma and style with which it is in 
 contact. This process is known as the Descent of the Pollen-tube, and 
 by it the male cell or antherozoid is brought into the ovarian cavity and 
 into the immediate presence of the ovule. It then finds the foramen 
 of the latter, contact and fusion of the male cell with the oosphere is 
 effected, and fertihzation is accomplished. 
 
 Among cryptogams, there are no such speciallj' adapted sites pro- 
 vided upon the plant-body of the parent for the germination of spores, 
 which reproduce upon any appropriate soil. They may be of two 
 sexes, the macrosjiore resulting in a gametophyte which produces 
 female cells, the microspore in one which produces antherozoids, or the 
 one gametophyte may produce both organs. In either case, the anthero- 
 zoids commonly tray el to reach the female cell. Fertilization occurs 
 very much as in phanerogarns, but no seed is produced, as will shortly 
 be explained, the embryo proceeding at once to grow and reproduce a 
 sporophyte. 
 
CHAPTER X 
 
 CARPOLOGY: FUNCTIONS AND STRUCTURE OF THE FRUIT 
 FRUCTIFICATION 
 
 Fructification and its Objects, — The changes effected by fertiHzation 
 extend to all parts of the flower and even to other parts of the plant. 
 A consideration of the objects of the process will prepare us to under- 
 stand the nature of the changes. The objects are (1) the production 
 and maturing of one or more seeds, including provisions for their pro- 
 tection and nourishment throughout the process, together with the 
 nourishment of the parts w^iich thus protect them; (2) provisions for 
 their transfer, still enclosed in their container, to a suitable place 
 for germination and the fixation of the latter there, or (3) provisions for 
 their exit from such container and (4) their transfer after such exit to 
 the place of germination and their fixation there. The combined pro- 
 cesses connected with the attainment of these objects is Fructification, 
 and the product thereof is the Fruit. 
 
 Fructification Results in the Death of Some Parts, the Stimulation of 
 Others. — It is clear that the energies of the plant should not l)e called 
 for in the further development or preservation of any parts of the flower 
 which .are not serviceable as a part of the fruit in the attainment of 
 the above-named objects, unless possibly they may possess some other 
 function foreign thereto, as, for instance, the action of the stamens of a 
 flower in which fructification has already begun, in fertilizing the ovules 
 of some other flower. We should, therefore, look (a) for the disap- 
 pearance or death of all floral parts not thus serviceable, and (6) for 
 the stimulation and development of those which are. That the first of 
 these two objects is an immediate result of fertilization is strikingly 
 and unhappily illustrated in the behavior of ornamental flowers in which 
 the latter process is allowed to take place. Those who produce for 
 the market the handsome and expensive flowers of orchids are obliged 
 to carefully exclude insects from their greenhouses. Valuable flowers 
 which, without fertilization, would last for several weeks, wither and 
 die within a few days, or even hours, after such process has occurred. 
 That the accomi)lishment of the second-named object is no less imme- 
 diate is apparent upon considering the morphology of the fruit. 
 
A^^IT" PARTS DEVELOPED BY FRUCTIFICATION 103 
 
 Parts Useless in Fructification. — The only i)()rti()n of the flower which 
 is certain to he in no case utihzed in fructification, and, therefore, to 
 disappear after fertiHzation, is the actual stigma, and the stamens when 
 they are non-adlicrent. The stamens, as has been shown, may be ser- 
 viceable for other purposes, so that their death depends rather upon 
 the performance of their inchxichial function than upon fertihzation. 
 In proterogynons flowers this function is actuall\- stinnilate(l by the 
 conii)k'tion of fertiH/ation in their own flower. 
 
 Parts Useful in Fructification. — Upon the other hand, we are not 
 certain of a requisition in every case for the preservation and develop- 
 ment of any part other than the particular ovules which l)ecome fer- 
 tilized, the ovarian walls of the i)istil or pistils containing them (and 
 in some cases only a part of these), and of the torus. The death or 
 decay, therefore, of any or all of the other parts will be determined by 
 the indiA-idnal or class habit of the plant concerned. 
 
 Accrescent Parts. — To any part other than the ovary, which thus 
 develops and enlarges as a part of the fruit, the term Accrescent is 
 ai)plie<l. 
 
 Accessory Fruits. — Fruits of which such accrescent i)arts form the 
 conspicuous ])ortion are called Accessory fruits. 
 
 New Parts Developed by Fructification. — Finally, we must note that 
 new ])arts, of service in the fruit, frequently develop in the course of 
 fructiflcation, u])on either pericarj) or seeds, just as special a])])endages 
 develop u))on the floral organs for performing special function in con- 
 nection with pollination. That such additional parts exhibit little, if 
 any, (le\-eloi)nient (Jui'ing the floral stage, is due to the fact that an 
 enormous waste of energy on the i)art of the plant would thus be 
 involved. Of all the flowers j)roduce(l by a plant, only a niiiioi- ])ortion 
 usually accom])lish fructiflcation, and of all the ovules produced by any 
 gynaecium only a minor j)ortion usually produce seeds. The develop- 
 ment of these su])erfluous flowers and o\ules constitutes in itself a 
 serious waste, l)ut it is a necessary or, upon the whole, an economical 
 one, as it tends in the end to secure the full degree of fructification by 
 tiie plant. The develojiment, however, upon such superfluous flowers 
 or ovules, of parts which will be of value only in case fructiflcation is 
 effected, would be anything l)ut (>cononiieal. Hence the general 
 rule that ])arts of the fruit which are of no use in elfiM-ting ])ollination 
 and fertilization are not (le\-elope(l until after these functions are 
 performed. 
 
104 CARPOLOGY: FUNCTIONS AND STRUCTURE OF THE FRUIT 
 
 FRUIT 
 
 Structural and Physiological Senses of the Term, — There are two dis- 
 tinct senses in which the term "fruit" may be employed. In the first 
 instance, we may regard it as the structural product of the develop- 
 ment in fructification of a pistil, or in the second as an organ performing 
 a certain reproductive function or functions. The limitations of our 
 definition of the term will vary accordingly. 
 
 Entire Gynaecium as the Fruit. — In many cases the ripened gynaecium 
 performs or may perform the fruit-function entire, as in the cherry, 
 the strawberry, the blueberry, the so-called "seed" of the sunflower, or 
 the pod of the bean or digitalis. In such cases the solitary ripened 
 carpel (cherry and bean) or the aggregation of ripened carpels (as in the 
 other illustrations), of a gynaecium, constitutes the fruit, from either 
 point of view. 
 
 Either the Whole or Part of a Gynaecium as a Fruit. — In other cases the 
 several carpels of a gynaecium are separate from first to last as pistils, 
 as in the case of the buttercup. The entire collection then constitutes 
 a fruit, being the product of a flower, but each of the individual pistils 
 must also, from a physiological standpoint, be regarded as a fruit, inas- 
 much as it performs the fruit function independently. 
 
 Part of a Pistil as a Fruit. — Again we find, as in the case of the borage, 
 that carpels originally coherent, separate before performing their 
 function, so that we must regard each of the separated carpels, as well 
 as the entire gynaecium, as in the nature of a fruit. 
 
 Part of a Carpel as a Fruit. — Occasionally even a carpel will itself 
 divide into separate parts, each of which is equally entitled to be 
 designated as a fruit, as in the case of the 2 carpels of the lavender, 
 which separate into 4 nutlets. 
 
 Gynaecia of a Number of Flowers Forming a Fruit. — In still other cases 
 the ripened gynaecia of more than one flower cohere and perform the 
 fruit function as one body, as in the case of the partridge-berry, the 
 fig, and the mulberry. 
 
 Finally, we note that many fruits can perform their function in either 
 way — namely, by means of their carpels, or parts thereof individually, 
 or as aggregations proceeding from a single flower (blackberry), or 
 from many flowers (fig, hop, etc.). It is, therefore, to be noted that 
 that which is at one time to be regarded as a fruit is at another time 
 only a part of one, according to the manner in which it performs its 
 function. 
 
THE PERICARP 105 
 
 Kinds of Fruits. — From the foregoing considerations, we may deduce 
 the following definitions of fruits: 
 
 A Fruit is a separate ripened carpel, or a separate part thereof, or an 
 aggre,c;ation of ripened carpels, together with any adherent j)arts. 
 
 Multiple or Collective Fruits are those proceeding from the gynaecia 
 of more than one flower. 
 
 Aggregate Fruits are those which proceed from a number of pistils 
 of one flower. 
 
 Simple Fruits are those proceeding from a single pistil. 
 
 Apocarpous Fruits are those consisting of one carpel or of two or 
 more non-coherent carpels. 
 
 Syncarpous Fruits are those consisting of coherent carpels. 
 
 Accessory Fruits are those in which some part other than the ripened 
 ovary constitutes a conspicuous portion. 
 
 Structural Composition of the Typical Fruit. — The student cannot have 
 failed to note in reading the above statements that the composition of 
 the fruit is extremely variable and in some cases complicated. In 
 accordance with this fact, the classification of the parts of fruits is 
 o])en to great differences, according to the principles upon which the 
 observer bases his classification. The typical fruit may be considered 
 as that which consists only of the ripened pistil with the contained seed 
 or seeds. 
 
 The Pericarp. — As a fruit is regarded as possessing but two portions, 
 namely, the seeds and the Pericarp, the pericarp of such a tyi)ical fruit 
 would consist of a ripened })istil exclusive of its seeds, but since, in many 
 cases, the calyx, disk, or other part is closely adnate to the wall of the 
 ovary and more or less indistinguishable from it, it becomes imprac- 
 ticable to restrict the term pericarp to a part consisting only of the 
 pistil. Again we find that there are all intermediate forms and degrees 
 of adnation and sei)aration between the ovary and the accrescent ])arts 
 of accessory fruits. It, therefore, appears most convenient to define 
 the pericarp in a broad sense as the fruit with the exception of the 
 seeds. 
 
 The Pseudocarp or Anthocarp. — AVhen the pericarj) consists chiefly 
 of other elements than the ovarian wall it is called a Pseudocarp or 
 Anthocarp. 
 
 Layers of the Pericarp. — When the pericarp is seen to consist of three 
 demonstrable layers, these are called respectively Fxocarp, the outer; 
 Endocarp, the inner; and Mesocarp, the middle. When the exocarp 
 is thin and membranous, like the skin of a plum, apple, or tomato, 
 
106 CARPOLOGY: FUNCTIONS AND STRUCTURE OF THE FRUIT 
 
 it is called an Epicarp, and when an endocarp is hard and strong inside 
 of a fleshy layer, like the stone of a peach or the "core" of an apple, it 
 is called a Putamen. 
 
 Modes of Performance of the Fruit Functions. — We shall now consider 
 the maimer in which tlie fonr objects of fructification are accomplished 
 through the modifications effected in each of the floral parts and in 
 the parts adjacent, by fertilization, including such new appendages 
 as are thus caused to develop. 
 
 Growth and Maturity. — The development and maturity of the fruit 
 are eft'ected by the stimulation, through fertilization, of the nutritive 
 functions of the pistil, the torus, adjacent portions of the plant, and 
 through the combined influence of all the flowers, a similar stimulation 
 of all portions of the plant. 
 
 Protection. — So far as the development of a protecting container for 
 the maturing seed is concerned, the object in general demands the 
 development of nothing more than the ovarian wall; but the effects of 
 adnation and the requirements of the other objects result in the exten- 
 sion of this process to various other parts of the flower or even of its 
 supporting parts. The development of such parts in connection with 
 the ovarian walls will therefore receive attention in considering the 
 methods by which such other objects are accomplished. 
 
 The Abortion of Septa and Cells. — It has been stated that not always 
 are all of the ovarian walls involved in fruit development. A gynae- 
 cium possessing several pistils may fail to develop one or more of them 
 in fruit, and when these are adnate into a compound o^'ary, as in Val- 
 lesia, one or more of them may likewise fail to develop. A several- 
 celled ovary, as in Calesium (Fig. 279), may, after the fertilization of 
 one or more ovules in one or more cells, permit the abortion of those in 
 the other cells, the septa of the latter being then crowded against the 
 outer wall by the growing seeds, or even disappearing, so that the fruit 
 will contain a smaller number of cells than the ovary which produced it. 
 The partial obliteration of cells in a similar manner is well shown in the 
 fruit of Diospyros {Fig. 280). 
 
 Mr. J. H. Hart has contributed three fruits taken from one crop of 
 a single plant (Fig. 285, a, b, and c), the first showing the development 
 of all three of the ovarian cells, the others having respectively one and 
 two of these aborted. 
 
 The Development of New Septa and Cells. — x4dditional walls, upon the 
 other hand, may develop during fructification. Datura has a 2-celled 
 ovary (Fig. 221), but a 4-celled fruit (Fig. 223), and this occurs regularly 
 
TRAASl'ORTATIOX OF THE FRUIT 
 
 107 
 
 in the Labidfar. Tlie newly formed walls are not always vertical. The 
 fruit of Arsrlii/noiiwne (Fig. 351) and that of Sophora (Fig. 352) divide 
 trans\(M-seiy into one-seeded joints. 
 
 Special Defensive Provisions, ("oneerning the protection of tlii' fruit 
 and seeds, we note that its full accomplishment often calls for other 
 defensive i)rovisions than those against merely mechanical forces, in 
 the form of appendages constituting an armor. These are sometimes 
 an outgrowth from the ovary itself, as in Sfnuiioniinn (Fig. 282), some- 
 times u])on an enclosing calyx (Fig. 283), an enclosing wall consisting 
 of a hollowed branch, ;is ni tlu> i)rickly pear (Fig. 281 ), or soinetiines upon 
 
 Fig. 279. Cro-ss-sfction of yoiiiiK fruit of Calcsium, the cells tlisappuiiriiis; uxicpt that in wliich an 
 ovule has been fertilized. 2S0. Diospyros, the same. 2S1. Fruit of Opuntia, immersed in prickly end 
 of branch. 282. F'ruit of Datura, with prickly ovary. 283. Of Riancjc, with prickly calyx. 284. Of 
 Castena, with prickly involucre. 285. Three palm-fruit.s from the same tree, with one or two, a, with 
 none, of the cells aborted. 
 
 an enclosing involucre, as in the chestinit burr (Fig. 284). At other 
 times the protection is secured by develoi)ing acrid or otherwise dis- 
 agreeable pericarps, as the husk of the walnut or the pulp of the colo- 
 cynth. These defences may be ett'ective only during the maturing stage, 
 as already pointed out, or their deterrent action may be permanent. 
 In tlie same direction are to be considered the effects of ])oi.sonous 
 principles proper and the inedible nature of a pericarp pending the 
 maturing of the seed, })ut which afterward becomes edible. 
 
 Transportation of the Fruit.- The transfer of the fruit to the jjlace of 
 germination is securetl by inctliods which for the ni(»t part admit of 
 
108 CARPOLOGY: FUNCTIONS AND STRUCTURE OF THE FRUIT 
 
 classification. We shall first consider those provisions which utilize 
 the agency of the wind for this purpose. 
 
 Transportation by the Wind. — We note, first, that the weight of fruits 
 to be thus transported is reduced to a minimum. They are in almost 
 all cases one-seeded (Monospermous), the loss due to this character 
 being made good by the fructification of a large number of flowers. 
 The one-seeded condition of such fruits is not restricted to families 
 which are characterized by it. Many fruits of the Leguminosae, which 
 are commonly several- or many-seeded, as the pea and bean, become 
 one-seeded when adapted to wind-transportation (Figs. 296 and 299). 
 Fruits which are not one-seeded may divide into one-seeded parts, 
 easily separable, to facilitate transportation by wind or other agencies, 
 as has already been shown. 
 
 Morphology of Fruit-wings.— Such a state having been attained, the 
 action of the wind upon them is next secured through the development 
 of an expanded surface of some kind, commonly a wing or plume. 
 In the Platypodium (Fig. 296) it is the entire wall of the ovary, in its 
 original nature a pod, like that of the bean, which becomes developed 
 into a wing. In the elm (Fig. 287) it is likewise the ovarian wall. In 
 the carrot (Fig. 288) and the Rumex (Fig. 289) it is an enclosing accres- 
 cent calyx. In the Piptoptera (Fig. 290) it is two accrescent lobes of 
 such a calyx. In the Zinnia (Fig. 291) a persistent corolla performs 
 the same office. In the hop (Fig. 292) an accrescent bract is made to 
 serve the office of a sail. The fruit of the Cardiospermum (Fig. 294) 
 represents a class in which the thin pericarp, instead of being expanded 
 into a wing, is inflated into a balloon-shaped receptacle, subserving a 
 similar purpose. Plumes, consisting of the modified persistent calyx, 
 are seen in the Valerian (Fig. 293) where it is present, though concealed 
 by a circinate praefloration, from the flowering stage, while in the 
 Phyllactis it is not developed until after fructification begins. A 
 plumose style is seen in Pulsatilla (Fig. 286). 
 
 Transportation by Attachments. — We shall next note the cases, per- 
 haps even more numerous, wherein use is made of passing bodies by 
 providing such appendages as shall serve to attach the fruit to them. 
 Fig. 298 represents the fruit of a Rumex, in which the calyx is divided 
 into hooks for this purpose. Fig. 297 shows another species, in which 
 this method is combined with wind transportation, a combination which 
 is very common among the Umbelliferae. The accrescent calyx teeth 
 (awns) of Verbesina (Fig. 295) are adapted to piercing passing bodies, 
 while at the same time the adnate tube is winged. In Bidens (Fig. 300) 
 
TRANSPORTATION OF THE FRUIT 
 
 109 
 
 similar awns arc ])ar}H'(l and adhere very tightly to anything which 
 they may pierce. In the case of the burdock (Fig. 301) it is an involucre 
 which bears such hooks. Similar hooks are found upon the outer 
 wall of the ovary itself in many cases. Sometimes the style is recurved 
 at the apex, thus forming a terminal hook, while at others (Fig. 302) 
 the apex, after performing the stigmatic function, falls away, but leaves 
 a hooked lower joint to become efl'ective in the fruit. The attachment 
 is not alw^ays thus secured by means of distinctively piercing appendages. 
 The surface may be rendered adhesive in other ways, as seen in the 
 minute structures covering the fruit of Desmodium. 
 
 Fig. 286. Fruit of Pulsatilla, with plumose style. 287. Winged epicarp of Ulmus. 288. Of carrot. 
 289. Winged calyx of Rumex. 290. Of Piptoplera. 291. Winged petal of Zinnia. 292. Winged 
 bract of hop. 293. Plumose calyx limb of Vahriaita. 294. Inflated pod of Cardiospcrmum. 295. 
 Winged akene of Virhesina. 290. Winged legume of Plalypodium. 297. Winged and hooked calyx 
 of Rumex. 298. The same, hooked only. 299. Winged legume of Plerocarpus. 300. Hooked calyx 
 of Bidens. 
 
 Trans porf (if ton through Edible Pericarps. — We shall next consider 
 another large class of fruits, which dci)end for their trans])()rtation upon 
 the possession of cdil)le pericarps or edible portions of them. Such 
 fruits may be eaten with the contained seed, as in the case of the straw- 
 berry or small cherries, in which case transportation is effected during 
 the process of digestion of the pericarj); or, as in the case of the peach 
 and ])lum, the fruit may be too large for such process, depending for 
 trans])ortation upon carriage by a ])arent to its young. In still other 
 cases they are of such a nature that they can be carric<l and stored for 
 
110 CARPOLOGY: FUNCTIONS AND STRUCTURE OF THE FRUIT 
 
 winter use. The edible portion is in some cases, as in that of the banana, 
 highly nutritious, while in others it is apparently eaten merely for its 
 palatability or for its thirst-quenching properties. 
 
 Special Protection to Seeds of Edible Fruits. — Some special form of 
 protection is commonly required for the seeds of edible fruits. That 
 of the peach is enclosed in a hard stone, so that it shall not be a})raded 
 as the pulp is pecked or bitten away. Those of the cherry and straw- 
 berry are enclosed in similar hard coats, which resist the digestive process 
 as well. The more or less laxative or purgative properties of many 
 fruits doubtless contribute to such protection by the more prompt 
 dejection of the seeds which is brought about by their action. 
 
 J(?P. 
 
 Fig. 301. Lappa fruit with prickly involucre. 302. Fruit of Gt-um with jointed .style. 303. Fruit 
 of Gaulthcria, with fleshy calyx. 304. Of strawberry, with fleshy torus. 305. Of blackberry, with 
 fleshy torus and ovaries. 306. Of cashew, with fleshy pedicel. 307. Of tamarind, with fleshy middle 
 layer of pod. 308. Of apple, with fleshy calyx and disk. 309. Of papaw, with fleshy inner layer of 
 ovary. 310. Of belladonna, with fleshy ovary. 311. Of fig, with fleshy hollowed end of branch. 
 312. Of watermelon, with fleshy placentae. 
 
 Origin of Edible Portion. — The origin of the edible portion is various. 
 In the strawberry (Fig. 304) it is the complete torus, and this only. In 
 the blackberry (Fig. 305) such a torus is combined with a partially 
 fleshy ovarian wall upon each of the ripened pistils. In the rose (Fig. 
 59) it is a similar torus, but hollowed, probably with other elements 
 combined. In the apple (Fig. 308) it is a fleshy-thickened disk, together 
 with the adnate calyx lined by it. In the checkerberry (Fig. 303) it is 
 the calyx only which becomes fleshy. In the gooseberry it is the calyx 
 and the entire ovary, but without any disk, while in many other berry- 
 like fruits it is the ovary alone. In the plum and cherry not all of the 
 
SPECIAL !>h'<)\/SI(>XS FOR I'RFA'KNTI N(i TUAXSl'OUTA TION 1 1 1 
 
 ovarian wall is edible, its endoearp heeomiiifjj a putaiiieii. In the lemon 
 (Fig. 329), the papaw (Fig. 309), and the pnnipkin it is the inner i)ortion 
 which is edible, while the outer is not. In the waterniclon the ])lacentae 
 comprise almost the whole of the e(lil)le ])ortion (Fig. '.\V1), while in the 
 tamarind it is the middle layer of the ovary (Fig. '.\()1). 
 
 Edible Portions Not Pertaining to the Flower. — In all of the above- 
 mentioned cases it is some one or more of the parts of the flower which 
 eventually forms the edible i)eriear]), but there are numerous cases in 
 which other parts of the plant contribute to or form the whole of such 
 l)()rti()n. In the Cashew (Fig. ;>()()) the ovary (a) enlarges but little, 
 while the j)edicel {b) undergoes a great enlargement and becomes 
 edible. In the cactus (Fig. 281) the end of the branch is hollowed out 
 and the wall so formed l^ecomes the edible pericarp of a single flower. 
 In the fig (Fig. 311) we have a similar hollowed branch, but instead of 
 being occui)ied by a single flower, the wall is lined by a great number of 
 them. 
 
 Miscellaneous Methods of Transportaiion. — Besides the more common 
 methods of seed distribution referable to the pericarp, which are thus 
 subject to classification, we find numerous special devices which cannot 
 here be enumerated in detail. Fruits which grow beside or in the 
 vicinity of streams or other bodies of water are commonly adapted in 
 some way for using the latter as a vehicle for transportation. They are 
 freqnently of a rounded form and of considerable weight, so that njion 
 falling they will roll into the water, where they are then enal)le(l to 
 float i)y virtue of low specific gravity, due often to the presence in them 
 of large cavities, as in the case of the cocoanut. The pericarp is in such 
 cases usually furnished with some means of protection against the action 
 of the water. The fruit of a s])ecies of Arena is so constructed that by 
 the change of form and position of its long awns in dry and wet weather, 
 respectively, it is enabled to tra\"el. 
 
 Special Provisions for Preventing Transportation.— Finally, we must 
 note that some fruits are ])rotected by special devices against trans- 
 portation. Thus, the mangrove possesses a seed which germinates while 
 still attached to its parent and which does not sever its connections 
 therewith until the young ])laiit has descended many feet and fixed 
 itself into the nuid below. The jx'annt, after antlu'sis, drixcs its o\ary 
 beneath the surface of the soil, where its fruit is dexcloped ( h'ig. .■!]:!). 
 Plants ])()ssessing such habits are ahva\s highly gregai'ions, ()ccu])yiiig 
 the ground to the exclusion of all other species, thus .securing their 
 perpetuation even wliile their di.ssemination is prevented. The high 
 
112 CARPOLOGY: FUNCTIONS AND STRUCTURE OF THE FRUIT 
 
 degree of adaptation secured by the peanut is still further illustrated 
 by its apparent power to support itself by means of these buried 
 branches, should the parent stem in any way become severed; a very 
 important protection, in view of the highly nutritious character of the 
 herbage, which renders it liable to partial destruction by grazing 
 animals. 
 
 <3/J. 
 
 Fig. 313. Peanut plant, with buried fruits. 
 
 The Fixation of Fruits after Distribution. — The fixation of many fruits 
 with their contained seeds is secured by a series of devices no less 
 interesting than those which effect their distribution. Fruits like those 
 represented in Figs. 75, 76, etc., are commonly more or less sharpened 
 or narrowed at the lower end, which is much the heavier, so that they 
 shall the more readily penetrate a favorable surface. Their bodies, 
 moreover, are commonly toothed or hispid upward, so that the tendency 
 is for them to sink more and more deeply until properly interred. The 
 fruit of Viscum, whose seed can develop only upon the bark of trees, 
 
DEHISCENCE 113 
 
 is intensely adhesive, so that in i'alHng it does not readily })ound away, 
 bnt l)eoomes adherent to the first sohd l)ody wliich it eneonnters. 
 
 Provisions for Scattering Seeds. — As a rule, fruits whieh are provided 
 with special dexiees for their transportation are not designed for the 
 discharge of the contained seed, which escapes accidentally or germin- 
 ates while still enclosed. Provisions for the discharge of seeds, therefore, 
 ordinarily apply only to such fruits as complete their function at the 
 place of origin. For provisions for the distribution of such plants, we 
 should naturally look to the seeds themselves; yet to this rule there are 
 mnnerous exceptions, for many fruits which never leave the place of 
 growth yet possess various devices for distributing their seeds over a 
 greater or less area by \irtue of forces inherent in their pericarps. The 
 common name of the Impatiens, "touch-me-not," is derived from the 
 habit of its fruit of exploding with much force, discharging its seeds 
 meantime to a considerable distance. The fruit of Iliira similarly 
 explodes, and with such violence as to cause a report like the discharge 
 of a firearm. Elaterium (Fig. 314), during the ripening process, collects 
 by osmosis within its cavity an amount of liquid which exerts a powerful 
 outward pressure upon the pericarp. When fully rijjc, the slightest 
 contact with another body causes the pericarp to leap away from its 
 attachment, with the production of a hole at its base through which 
 the seeds are expelled with much force. 
 
 Dehiscence. — The ordinary method of providing for seed discharge is 
 by means of a splitting of the pericarp known as Dehiscence. 
 
 Dehiscent and Indchiscent Fruits. — A fruit so splitting is said to 
 Dehisce, and is known as a Dehiscent or Dehiscing fruit. Other fruits 
 are called Indehiscent. True dehiscence is longitudinal, although the 
 term is not altogether denied to other forms, provided the line of 
 separation is regular and constant (Figs. 325-327). 
 
 The Valves. — The parts into which pericarps dehisce arc called 
 Valves. The valves may separate entirely or remain attached in 
 various ways. 
 
 Forms of Dehiscence. — Dehiscence may occur at the ventral or at the 
 dorsal suture or at both. If at the ventral, then the carpel (Fig. 349), 
 or each carpel if it be i)art of a ])olycarpellary ])istil (Fig. 310), will be 
 left entire. If the polycar])ellary ])istil have se\eral cells, xcntinl 
 dehiscence must involve the separation of the carjjcls by the si)litting of 
 their walls or septa, whereas in the one-celled form se])ta do not exist 
 or are incomplete. Nevertheless, the principle is identical in the two 
 cases, and the former mode is called Septicidal dehiscence (Fig. 316). 
 8 
 
114 CARPOLOGY: FUNCTIONS AND STRUCTURE OF THE FRUIT 
 
 In such case the carpels, after separating through their septa, are not 
 necessarily open, and unless the dehiscence shall follow the wall into and 
 
 my 
 
 ^ ti'f 
 
 J/4 
 
 SIS. 
 
 3/6. 
 
 3/7 
 
 Fig. 314. Fruit of Elateriuvi discharging its seeds and watery contents. 315. Loculicidally dehiscent 
 pod of 7ns. 316. Septicidally dehiscent pod of Hypericum. 317. Transverse diagram of a margini- 
 cidally dehiscent pod. 
 
 Fig. 318. Apical dehiscence of Cerastium. 319. The same, Eucalyptus. 320. Circumscissile dehis- 
 cence of Mitracarpus. 321. Basal dehiscence of Jussiaea. 322. The same in Cinchona. 323. Apical 
 dehiscence of Ladenhcrgia. 324. Dehiscence by apical plug (6) in Berlholetia. 325. Apical dehiscence 
 of Psyllocarpus. 32C. Oblique dehiscence of Slaelia. 327. Partial dehiscence of Jeffersonia. 328. 
 Dehiscence by apical pore in Siphocampylos, 
 
 through the ventral suture, which it more frequently does not, the 
 dehiscence will be Incomplete and the carpels may even act as separate 
 indehiscent fruits. If dehiscence occur at the dorsal suture (Fig. 315) 
 
DEHISCENCE 115 
 
 it must separate the wall of the cell into two parts, and this form is 
 called Lociilicidal dehiscence. By an intermediate form, the dehiscence 
 takes place at the point where the septum joins the outer wall (Fig. 317), 
 the IMarginicidal form. Various other modifications and combinations 
 of the two forms may be discovered, but do not call for a notice in this 
 work. 
 
 Mechanism of Dehiscence.— Dehiscence is secured by a peculiar adap- 
 tation of the fil)ers to the other tissues and to the form of the fruit. 
 
 Incomplete Dehiscence. — \^arious forms of imi)erfect or incomplete 
 dehiscence are those in which it commences at the apex and fails to 
 extend itself to the base, as in Cerastium (Fig. 318) and EvcalyjJtus 
 (Fig. 319), or in which it commences at the base and extends only 
 partially toward the apex, as in Jnssiaea (Fig. 321) and in Cinchona 
 (322). Important pharmaceutical decisions have rested upon the 
 question of basal or apical dehiscence. The true Cinchona barks have 
 all proceeded from species whose fruits dehisce as represented in Fig. 
 322, while those of the trees yielding the false barks dehisce as repre- 
 sented in Fig. 323. 
 
 Syecial Terms for Dehiscence. — The manner in which true dehiscence 
 passes into false or transverse dehiscence, called Circumscissile, is well 
 displayed by Figs. 325, 32G, and 320, viewed in the order named, all 
 illustrations of closely related plants. A very curimis form of special 
 dehiscence is that of Jeffersonia (Fig. 327). 
 
 Rupturing. — Dehiscence is not the only method by which fruits 
 open to discharge their seeds. Rupturing fruits are those which oj)en 
 by an irregular line. 
 
 Dehiscence by Pores. — Some portion of a pericarp may decay quickly, 
 leaving an opening, or the same result may be secured by excessive 
 shrinkage in drying of the more delicate tissue of some part of the 
 Pericarp, as in Fig. 328. Openings of this kind are called Pores. Our 
 consideration of this subject will close with an illustration of the fruit of 
 the Bcrtholctia, or Brazil-nut (Fig. 324). The apex of this enormously 
 thickened and strongly hardened pericarp consists of a small circular 
 portion coiniected with the remainder by a circle of tissue which quickly 
 decays, making the former removable as a plug and thus leaving an 
 apical pore. 
 
CHAPTER XI 
 
 CLASSIFICATION OF FRUITS 
 
 A PERFECT or even fairly satisfactory classification of fruits has never 
 been presented, and this is impossible, except through a complete 
 revision and uniform agreement of terminology, based upon a uniform 
 set of principles. A classification of some sort is, however, an essential 
 in pharmaceutical botany, and such an one is here presented as appears 
 most serviceable to those for whom it is intended. 
 
 Two Principles Involved. — Among all the various systems which have 
 been proposed, two fundamental principles have been observed — first, 
 the morphological structure; second, the physiological features. By the 
 first, fruits have been classed according to the character and number 
 of the parts entering into their formation and the modifications which 
 these have undergone in fructification; by the second, according to the 
 structural and functional characters as seen in the complete fruit, 
 without regard to their mode of origin. As characters of the latter 
 kind exist for the sake of the offices which they are to fulfil, it is clear 
 that physiology forms the basis of the latter method of classification. 
 Although it is impracticable to follow either system without some regard 
 to the other, it may be said that to follow in the main the morphological 
 plan is the more scientific, the other the more convenient and the more 
 practical, especially in economic work. The latter is, therefore, the plan 
 which is here adopted. Fruits possessing pericarps fitted for transpor- 
 tation (a of our table) will then form the first of our two classes, while 
 those fitted for discharging their seeds i'??. situ upon maturity will form 
 the second {e of the table). 
 
 F'or a few fruits not readily introduced to this key, and for some 
 exceptions, the explanations which follow may be consulted: 
 
 Fruits with pericarp designed for transportation (a). 
 
 Fruits with pericarp not designed for transportation (e). 
 f With fleshy pericarp (Carnose) (b). 
 ( With non-fleshy pericarp (Siccose) (c). 
 [ With seeds embedded in a soft endocarp (g). 
 \ With seeds enclosed in a putamen (h). 
 
nvo I'lilXCIPLES INVOLVKI) ]]? 
 
 f With ;m (Midosiiig involucre, at least hcforc maturity (/). 
 
 ( Without an enclosintj iiixolucre [d].* 
 
 \ AVrticall\- (JixisiMc in onc-sccdcd j)arts (/). 
 
 I A one-set'ded ]);irt resulting from such division (j). 
 
 I Transversely divisible into one-seeded joints (n). 
 
 Not divisible into one-seeded ])arts nor the produet of such 
 I di\-ision (/,•). ^ 
 Not transversely dehiscent (/). 
 Transversely dehiscent (f/). 
 Monocarpellary (?»)• 
 
 Dicarpellary, the valves sei)arating from the placentae (o). 
 I Not monocarpellary nor dicarpellary, with valves separating 
 [ from placentae {y). 
 
 r Soft throughout Berrv. 
 
 •j' With a soft, tough rind Hesperidium. 
 
 I With a hardened rind Pepo. 
 
 ^ Putamen of bony hardness; solitary Drupe. 
 
 Putamen of bony hardness; one of several which are 
 
 coherent Pvrene. 
 
 Putamen of bony hardness; one of many which are 
 
 non-coherent Drupelet. 
 
 Putamen thin and tough Pome. 
 
 Schizocarp 
 
 (If dicarjx'llary, with a cari)ophore .... Cremocarp). 
 
 Part of a cremocar]j ]\Iericarp. 
 
 Not part of a cremocarp . . . .Coccus, Xucula, or Nutlet. 
 Dehiscent, the vahes separating from the two 
 
 placentae :\Iost Silicles. 
 
 With thin, winged pericarp Samara. 
 
 With inflated pericarp Utricle. 
 
 Pericarp, thickish in view of its size, not inflated, 
 
 sometimes winged Akene. 
 
 r A non-glumaceous involucre, with contents (dans. 
 
 I A one-seeded fruit from a glans Kut. 
 
 I A glumaeeous involucre with contents . . . A few Spikelet.s. 
 
 I A one-seeded fruit from a spikel(>t Caryopsis. 
 
 f Dehiscing by one suture only Follicle. 
 
 I Dehiscing by both ventral and dorsal sutures . . Legume. 
 I (When spirally coiled ("ochlea). 
 
 Exceptions occur. 
 
118 CLASSIFICATION OF FRUITS 
 
 n . Loment. 
 
 ^ I Elongated Silique. 
 
 I Short Some Silicles. 
 
 y Capsule. 
 
 q Pyxis. 
 
 The fact, as stated above, that custom has not been uniform in the 
 application of the principles of classification leading to the above terms, 
 so that the latter are not employed in the same sense in different botan- 
 ical writings, renders it necessary that such a key as that presented 
 should be supplemented by a detailed consideration of the limitations 
 and modifications of each class of fruits. 
 
 The Berry (Figs. 281 and 310). — A fruit with a pericarp fieshy through- 
 out, with the exception of the epicarp. Good illustrations are the grape 
 and the belladonna. In these, the fruit contains little or no cavity 
 and the seeds are embedded in a soft pulp. This is the typical form, 
 from which we see a variation in the Tomato, in the direction of a 
 central cavity, which in the Capsicum becomes complete. The latter is 
 frequently called a capsule and connects the berries with the latter 
 class, but it is more properly grouped with the berries. A similar 
 modification, though more slight, is found in the checkerberry (Fig. 303) 
 and the cranberry. The term has also been applied to the pomegranate 
 and similar fruits, but these, however soft within, possess a distinctly 
 hardened exocarp and are not true berries. As will be seen farther on, 
 comparatively few of the fruits which are designated as berries in 
 common parlance are really such. The berry may possess one or more 
 cells. 
 
 The Hesperidium (Fig. 329) . — A berry-like fruit with a soft, but tough 
 rind. The term has never been applied to other fruits than those 
 related to the orange and lemon. They are several-celled. 
 
 The Pepo (Fig. 332). — A berry-like fruit in structure, usually hollow 
 and with an indurated rind. It is one-celled. Good illustrations are 
 the pumpkin and melon, and the application of the term is by most 
 authors restricted to the fruits of that family (the Ciicurbitaceae) ; 
 but it is entirely proper to extend it to such very similar fruits of other 
 families as the Calabash (in the Bignoniaceae) and the Pomegranate 
 (in the Punicaccae). 
 
 The Drupe or Stone Fruit (Fig. 333). — A fruit with a sarcocarp and 
 epicarp and a single thick bony putamen. Although typically one-celled 
 and one-seeded, the term is applicable to similar fruits with several 
 
THE SCIIIZOCARP 
 
 119 
 
 cells all enclosed in a single sarcocarp, bnt each seed possessing its own 
 putaiuen. Each jiiitamen with its own seed is then called a Pyrena or 
 Pyrene. Familiar illustrations of the tyi)ical drupe among medicinal 
 plants are the ])rune, sumach and pepper, and of the several-celled 
 form that of the RJiamnus, (Fig. 331) and the Phytolacca. As in most 
 classes of fruits, we find liere a gradation into other classes, most com- 
 monly into the Schizocarp. A peculiar fruit, in its general structure 
 related to the drupe, is the so-called legume of the tamarind, which 
 possesses an exocarp similar to that of a pepo, a distinct edible sarco- 
 carp and a crustaceous endocarp or putamen containing several seeds 
 (Fig. 307). 
 
 J^^. 
 
 33X. 
 
 JJJ. 
 
 Fig. 329. The hesperidium (lemon). 330. Sehizocarp of Urena. 331. Compound drupe, with 
 detached pyrena, of Rhamnus. 332. Transverse section of a pepo. 333. The drupe (plum). 334. 
 Dicarpellary sehizocarp of Labiatae. 
 
 The Psrrena (Fig. 331).- — (Already considered under Drupe.) 
 
 The Drupelet (Fig. 305, a). — Diifers from the Fyrcna in that it pos- 
 sesses not only its own separate putamen, but a sei)arate sarcocarp as 
 well. It is one of many small (Irui)es belonging to an aggregate or 
 multiple fruit. 
 
 The Pome (Fig. 308). — A fleshy fruit with a tliin chartaceous or cartil- 
 aginous putamen. It is several-celled. The term is commonly restricted 
 to fruits related to the ai)i)le. 
 
 The Sehizocarp (Figs. 2SS, 3.'>0, and 334). — The typical sehizocarp 
 should be delined as a fruit which divides septicidally at maturity into 
 one-seeded carpels. Because, however, schizocarps frequently vary in 
 the constancy and completeness with which they undergo this process, 
 they are defined as "divisible," rather than "dividing." There are, 
 moreover, cases in which they divide into one-seeded ])arts of cari)els. 
 The comprehensive definition, therefore, should be "dry fruits septi- 
 
120 CLASSIFICATION OF FRUITS 
 
 cidally divisible at maturity into one-seeded parts." Schizocarps are 
 commonly provided with appendages for wind-transportation or for 
 transportation by mechanical adhesion to passing bodies. Those forms 
 which, as above stated, are intermediate toward drupes are to be 
 classed in one or the other class, according to whether such appendages 
 for distribution, or that of an edible pericarp, is the more pronounced. 
 Even schizocarps which are not cremocarps may possess a carpophore, 
 as in geranium, though commonly they do not. 
 
 The Cremocarp (Figs. 247 and 288). — A di-carpellary schizocarp, the 
 carpels attached toward their summits to a slender carpophore, from 
 which they usually only incompletely separate at maturity. The term 
 is restricted to the fruits of the UmbeUiferae. They are commonly 
 provided with appendages for fixation to passing bodies, frequently 
 for wind-transportation, and not rarely combine these two methods 
 of distribution. {Coniiim, Celery, etc.) There is no class of fruits which 
 possesses a greater importance in pharmacy, and hardly any whose 
 histological features are of greater interest. The plane of separation is 
 called the Commissure, a term applicable to a similar plane in other 
 fruits. (See Mericarp.) 
 
 The Coccus, Nucula, or Nutlet (Fig. 330, a, and Fig. 334, a).— One of 
 the divisions of a schizocarp, and its nature has been explained in con- 
 sidering that group. The term nutlet is commonly applied when the 
 pericarp is hard and close to the seed. 
 
 The Mericarp (Fig. 247, either half). — One of the halves into which a 
 cremocarp is divisible. Occasionally they are self-separating at matur- 
 ity, but usually only incompletely so. They are one-seeded and possess 
 a completely adnate calyx and disk. The pericarp almost uniformly 
 possesses external appendages in the form of five or nine ribs, as is well 
 shown in cross-sections (Fig. 335, h). When nine, they are commonly 
 of two forms, alternating with one another. A part or all of them are 
 much subject to extension into variously appendaged or pinnatifid 
 wings (Fig. 336, a). Internally, the mesocarp is almost uniformly 
 traversed upon both the faces and the backs of the carpel by tubes 
 called Vittae (Fig. 335, a), commonly with suberous walls and filled 
 with volatile oil. The dorsal vittae alternate in position with the ribs. 
 Upon thin transverse sections these oil-ducts or vittae appear as per- 
 forations, and as to their number and position serve the most important 
 purposes in diagnosis and identification, as do also the ribs. These 
 fruits are dorsally compressed when broader from right to left (Fig. 
 336), laterally compressed when broader in the opposite direction. 
 
THE AKENE OR ACHEMUM 
 
 121 
 
 IMericarps are of three classes: (I) The Coelospermous, characterized 
 by the possession by the seed of a concave face (Fi^'. '.VA7, a); (2) the 
 Caiiii)yIosi)ernK)iis, characterized by the ])()ssessi()n of a loiigitiuHiially 
 grooved face (Fig. .'i'iS, a); and (3) the Ortliospermous, possessing a 
 plane face (Fig. '.V.]P>). 
 
 The Silicle. (See Sili(nie.) 
 
 The Samara.— All iiulciiiscent fruit witli a winged i)cricarp. "^I'liey 
 are commonly one-seeded, as well as one-carpel led, but may be more. 
 Typically, it is the ovarian wall or the tube of an adnate calyx which 
 develops the wing, but there is no reason why the term should not be 
 extended to include similarly transportable fruits with wings consisting 
 of the accrescent limb of a calyx (Figs. 288 and 289), or corolla (Fig. 291), 
 or a surrounding alate bract (Fig. 292). Commonly the samara possesses 
 but a single wing, unilateral, as in the ash (Fig. 3.')9), or circular, as in 
 the elm (Fig. 287), but not rarely more than one wing is present, as in 
 the maple (Fig. 340), or many Malpighiaceae (Fig. 342). 
 
 —-a 
 
 337 
 
 Kig. 335. Transverse section of an orthosperinous niericarp: 
 pressed mericarp, two of tlu> ribs winged. 337. Coelospermous 
 spermous mericarp of Conium. 
 
 33<S. 
 
 vitta; 6, rib. 330. Dorsall.v o( 
 L-riearp of coriander. 33S. Camp: 
 
 The Utricle (Fig. 341). — A one-seeded indehiscent fruit, the seed 
 enclosed in a thin, bladdery or inflated pericarj). It is commonly one- 
 celled, but occasionally several-celled. Ordinarily, utricles eventually 
 become irregularly rujjtured, l)ut in a few forms there is a regular 
 ventral opein'ng, ap])r()aching toward dehiscence. 
 
 The Akene or Achenium ( Figs. 71 to NO and ;M 1). A small, indehiscent. 
 one-seeded, seed-like fruit, the pci'icnrp soiiicw liat thickened and 
 entirely distinct from the (Miclo.scd seed. The aki-ne varies in many 
 directions toward other fruits. In many cases the pericarp is inclined 
 to be flesln- and in a few it tends toward dehiscence, thus sinuilating a 
 
122 
 
 CLASSIFICATION OF FRUITS 
 
 follicle. Some forms of the akene are distinctly winged, so that they 
 might, but for the relationship of the species yielding them to akene- 
 producing species, be with equal propriety classed as samaras. They are 
 in nearly all cases provided with some means for securing wind-trans- 
 portation or for attaching themselves to passing bodies, and yet there 
 are numerous cases in which such appendages have become entirely 
 obsolete. For these reasons, it becomes a matter of extreme difficulty 
 to frame a definition at once comprehensive and delimiting fpr this 
 group. The inferior akene is sometimes distinguished bj^ the term 
 Cypsela (Figs. 74 to 80). 
 
 Fig. 339. Samara of ash. 340. Of maple. 341. Utricle. 342. Several winged samara of Mascaffraia. 
 343. Vertical section of anthodium. 344. Vertical section of akene of buttercup. 345. Same of the 
 glans of black walnut. 346. Glans of Fagus, or beech-nut. 
 
 Note should here be taken of the fact that the latter is characteristic 
 of the largest of all families, the Compositae, in which the akenes of 
 the head are massed and partially, or sometimes completely, surrounded 
 and enclosed by an involucre, the whole constituting a multiple fruit to 
 which the name Anthodium (Fig. 343) has been applied. The anthodium 
 varies greatly in its character. Although usually many-flowered, it is 
 commonly few-, or even in rare cases, one-flowered. In those cases in 
 which the involucre completely encloses the akenes, it is commonly 
 appendaged for distribution in an entire condition, as in the burdock. 
 This condition connects the anthodium with the glans and the contained 
 achenium with the nut. Indeed, it is almost impossible to distinguish 
 structurally between fruits representing these two classes, as, for instance, 
 those of Xanthium and Fagus. 
 
 The Glans (Figs. 345 and 346). — A fruit consisting of an accrescent 
 and partially or (commonly) completely enclosing involucre containing 
 
THE LEGUME 123 
 
 one or more nuts. The involucre may be dehiscent, as in the chestnut 
 and hickory-nut, or indehiscent, as in the black wahuit (Fig. 345). In 
 some of its forms, the involucre of the glans tends to become fleshy. 
 Inasmuch, however, as the design of such pseudo-flesliy pericarps is 
 not that of subserving transportation by their f(K)d-])r()i)erties, they are 
 more appr()i)riately regarded as non-fieshy. Wliile dcjKMiding, Hke the 
 grasses, upon their gregarious habits for perpetuation, nut-yielding 
 plants are apparently in many cases distributed by the rounded form of 
 their coats and the readiness with which they are transported bj^ flowing 
 water. 
 
 The Nuca or Nut (Figs. 345, a, and 340, a). — The relationship of the 
 nut and its glans to the akene and its anthodium has already been 
 pointed out. The nut is in all cases much larger than the akene and its 
 pericarp commonly much thickened and very hard. 
 
 The Spikelet (Fig. 347). — A fruit possessing a glumaceous involucre 
 and pertaining to the Gramineae (grass family) and related orders. 
 This class of fruits, like the glans and nut, connects those fruits which 
 are adaj^ted to transportation with those which are not. Although, 
 in general, these plants depend for their perpetuation upon a highly 
 gregarious habit rather than upon provisions for distribution of their 
 fruits, yet the spikelets of some grasses are unmistakably so designed, 
 and are transported with their caryopses enclosed in the glurhes. 
 
 The Caryopsis or Grain (Fig. 348). — A seed-like fruit produced in a 
 spikelet, the oxarian wall and the seed-body closely adnate. 
 
 The FoIUcle (Fig. 349). — A monocarpellary fruit dehiscing by one 
 suture only, this the ventral, except in rare cases. 
 
 The Legume (Fig. 350). — A monocarpellary fruit, non-fleshy and 
 dehiscing by both ventral and dorsal sutures. Notwithstanding the 
 definition thus given, we have to record the fact that in accordance with 
 a different principle and construction, the title includes all fruits of the 
 natural order Leguminosae. It, therefore, becomes necessary to point 
 out that the fruits of this family are extremely variable, and this in 
 directions which frequently carry them widely away from both the 
 structural and the physiological characters of the legume. The pecu- 
 liarities of the tamarind have already been pointed out. In the fruit 
 of the Inga the dehiscent legume is filled with a large amount of juicy, 
 edible pulp, in which the seeds are embedded. In other species this 
 pulp is replaced by one of a powdery consistency, while in others it is 
 fleshy or subcorneous. A great many legumes of this family are not 
 only indehiscent, but winged and one-seeded, and thus are true samaras. 
 
124 
 
 CLASSIFICATION OP FRUITS 
 
 The fruit of tlie Dipteryx is one-seeded and is dehiseent, but the peri- 
 carp is enormously thickened and first flesliy, then spongy. That of the 
 Cassia Fistula lias its seeds enclosed in a pulp and partly separated from 
 one another by transverse septa. It is thus apparent that many 
 legumes pertain to our first, rather than to our second, division. 
 
 '•^SZ 
 
 '3S4. 
 
 3SS. 
 
 JS6. 
 
 Fig. 347. Spikelet of a grass. 348. Caryop.sis from last. 349. Follicle of Asclepias. 350. Legume 
 of pea. 351. Loment of Aeschynomene. 352. Loment of Sophora. 353. Cochlea of Prosopis. 354. 
 Silique of Cardamine. 355. Silicle of Aethiomena. 356. Silicle of Hexaptera. 357. Silicle of Succowia. 
 358. Capsule of poppy. 
 
 Two distinctive forms of the legume have become dignified by the 
 application of special names, as follows: 
 
 The Loment (Figs. 351 and 352) is a leguminous fruit which may or 
 may not be dehiscent, but which is separable at maturity by transverse 
 divisions into one-seeded parts. In the Aeschynomejie these parts are 
 adapted to fixation to passing bodies, or occasionally also much flattened 
 and expanded to act as samaras. In the Soyliora (Fig. 352) the joints 
 are smooth, hard and rounded, and highly elastic, so that, in falling 
 upon the stony soil, they are adapted to bounding and running to a 
 considerable distance. The term loment has also been extended to 
 include those siliques which display a similar character. 
 
 The Cochlea (Fig. 353). — A legume which is spirally coiled. 
 
THE SYCONIUM 
 
 125 
 
 The Silique (Fifj. 354). — A (li-('ar])cllary deliiscent fruit, the two valves 
 separating- t'roiii the mar<^ins of tiie phieentae at maturity, leaving the 
 latter attached tt) the torus and to a false septum, whieh divides the 
 siiicpie into two ])arts. The ])riii(i{)al modification of the silique proper 
 is into the loment-like form which we have already considered. These 
 loment-producing ])lants are commonly found in the vicinity of water, 
 and their fruits are adaj)ted to transportation by this method. A more 
 im|)ortaiit modification is into: 
 
 The Silicle (Fi^s. 'Ar>r^ to 357). — 'J'his difVers from the siH(iue not only 
 in being short and broad, but in possessing ordinarily some form of 
 adaptation to wind or other transportation, thus belonging in our first 
 class. 
 
 The Capsule (Figs. 318 to 238).— The typical capsule is to be defined 
 as a di- to polycarpellary longitudinally dehiscent fruit. From the 
 typical form, however, it varies in several directions to such a degree 
 
 SS^. 
 
 J60. 
 
 ^6i 
 
 <36Z 
 
 Fig. 359. Giilbalus of ./i/Nipcrus. 300. Strobile of Picca. 3()1. Strobile of hop. 302. Syconium of 
 fig. 303. Pyxis of henliano. 
 
 as to render it impossible to frame a perfect definition. The capsule 
 of the poi)py (Fig. 358) opens by a number of small pores at the summit, 
 and this is true of many other forms. In other cases the mode of opening 
 is by various forms of irregular dehiscence intermediate between the 
 longitudinal and tlic circumscissile. Finally, w(> must note that many 
 fruits, like those of some species of Passljlord, which possess no regular 
 or natural method of ()i)ening, are still classed as ca])sules by systematic 
 botanists. 
 
 The Pyxis (Fig. :!().')). — A circumsci.ssily dehiscent fruit. 
 
 The Syconium (Fig. 302). — A fruit consisting of a hollow branch, 
 becoming fleshy, its inner surface the recejitaclc for many >niall, 
 one-seeded, akcnc-likc fruits. 
 
126 CLASSIFICATION OF FRUITS 
 
 The Aeterio (Figs. 304 and 305). — An aggregate fruit, with an accres- 
 cent fleshy torus and many crowded pistils. 
 
 The Strobile (Figs. 360 and 361). — A multiple dry fruit, its elements in 
 the form of imbricated scales. 
 
 The Galbalus (Fig. 359).— A fruit similar to the last, but the scales 
 fleshy or much thickened above, so that the form becomes more or 
 less globular. 
 
 In conclusion, it may be remarked that to assign a name to a fruit 
 is insufficient in most cases, especially in those of aggregate and 
 multiple fruits, to designate its character. 
 
CHAPTER XII 
 THE SEED 
 
 Changes in the Ovule. — As in the case of the parts entering into the 
 formation of the pericarp, so in that of the part forming the seed — 
 namely, the ovule — it is well to precede our study of the changes which 
 it undergoes by a consideration of the objects to be attained thereby. 
 
 Development of the Embryo. — 
 The essential feature of the seed is 
 the possession as one of its parts 
 of a more or less rudimentary 
 plant, developed from the fertil- 
 ized oosphere, and known as the 
 Embryo, and capable of remaining 
 for a more or less extended period, 
 before germination, in a state of 
 suspended animation. 
 
 The development of the embryo 
 commences with the division of 
 the fertilized oosphere into two 
 cells, each of which grows and 
 becomes capable of itself dividing 
 similarly. The result of such cell- 
 propagation is the production of 
 a tissue and of a body which 
 becomes elongated through suc- 
 cessive transverse divisions of its 
 cells, or certain of them, and 
 broadened by their longitudinal 
 division. Several progressive forms reached by 
 this ])r()cess arc sliown in Figs. 305 to 3()8. 
 
 Provisions Required by the Embryo. — During the period intervening 
 between the beginning and the completion of seed-formation the 
 embryo requires nourishing, and provisions for this constitutes the first 
 requirement of the process. The further development and growth of 
 
 J66. 
 
 Figs. 364 to 368. Figures illustrating develop- 
 ment of the embryo; the vertical chain of cells is 
 the pro-embryo, the uppermost of them becomes 
 the caulicle and the enlargement the cotyledons. 
 
 the 
 
 ibr' 
 
 (hi 
 
 ring 
 
128 THE SEED 
 
 the embryo, between the time of germination and that of absorption by 
 it from the external world, calls for additional nourishment. This can 
 be met only by the storage as a part of the seed of an additional food- 
 supply. 
 
 Protection of the seed-contents during its development is only partially 
 afforded by the pericarp, and this office is supplemented by the coverings 
 of the seed itself, while its similar self-protection between the periods of 
 maturity and germination is a manifest necessity. 
 
 The transfer of the mature seed to the point of germination, or its 
 dissemination, and its fixation in a favorable site, have already been 
 referred to. We have seen that in many cases these offices are not 
 provided for by the pericarp, and we must look for such provision to 
 the seed itself. 
 
 Parts of a Seed. — The parts of the seed by which these several offices 
 are performed we find to be as follows: 
 
 The Perisperm.- — The source of food-supply during the germination 
 of the macrospore and development of the gametophyte we have seen 
 to be the portion of the nucellus external to the embryo-sac. Usually 
 more or less of this material remains during at least the earlier period of 
 the development of the embryo and contributes to the nourishment 
 of the latter. Occasionally it persists even in the seed condition. It is 
 then known as the Perisperm. 
 
 The Endosperm. — Inside the embryo-sac a further store of nutriment 
 is caused to develop as a result of fertilization, this constituting the 
 chief supply of the growing embryo. More or less of this also may 
 persist, and usually does, upon the maturity of the seed. It is known as 
 the Endosperm. 
 
 Albuminous and Exalbuminous Seeds. — As the embryo develops, it 
 stores within its own body more or less nutriment. At maturity we 
 may find that the entire store of nutriment has thus been transferred 
 to the body of the embryo, and the seed is said to be Exalbuminous, or 
 we may find more or less endosperm or perisperm, or both, when the 
 seed is said to be Albuminous, and this external nourishment is known 
 as the Albumin. In only a few seeds used in medicine does the albumin 
 consist in any part of perisperm. The chemical nature of the albumin 
 is extremely variable. It received its misleading name because of the 
 similarity of its function to that of the albumin of the egg. 
 
 Protection. — Protection to the embryo may be afforded by the albumin 
 when that is of the required consistency or composition, the conditions 
 of the latter being a mere parallel of those already considered under 
 
77/ A' IIIU'M 129 
 
 tlic siil)j(>ct ol" the pericarj). Moi-c IVcciiuMitly, Iiowcxcr, it is -ccurt'd 
 (Mitircl\' tlir()iiii;li the coats of tlit' seed. 
 
 The Scrd-codf.s. — Those may con-csijoiid to the coats of the o\ul(', 
 though usually tiie i)riiniiie is found to have (lisa])])('ar('d. When it 
 persists it takes the name of Tegmen, or Endo])leura, the secundine 
 hecomino; the Testa, or Exopleura. Rarely tlie secundine also disa])i)ears 
 and the seed is Naked. The seed will also be naked when ])roduced from 
 a naked ovule. 
 
 Tlir Micropiilc. — When one or both of the coats persists, the point 
 where the foramen, now closed, existed becomes the Micropyle. 
 
 The Aril. — Frecjuently the develoi)ment of a new coat external to 
 the others is induced by fertilization, and this is known by the general 
 name of Aril. If it develop from the chalaza or a lower point, it is called 
 an Arillus, or True Aril; if from the micropyle, an Arillode, or False 
 Aril. 
 
 Dissemination. — The provisions of the seed for securing dissemination 
 are in most res])ects comparable with those afi'ecting the pericarp. 
 Wind-distribution is preeminent, that by fixation to passing bodies is 
 fre(iuent, and that by means of an edible coat is rare. 
 
 Fixation. — The fixation of seeds disseminated without the pericarp is 
 favored by their small size, enabling them readily to enter crevices and 
 cavities, and by peculiarities of surface which fa\()r the same process. 
 
 The large number and importance of medicinal seeds lend great 
 importance to their study by the i)harmacogn()sist, and this is especially 
 true of the histology of all their ])arts. Inasnnich, however, as the 
 subject of histology has been referred to a se})arate ])ortion of the work, 
 we shall here consider only such characters as can be distinguished 
 by means of an ordinary lens. 
 
 The Hilum. — The hiluni is in most cases readily perceptible, but is 
 occasionally found only by minute examination. It is to be studied as 
 to its position, size, form, surface, and color. Its position is sometimes 
 fixed with reference to the form of the seed, as at the larger or smaller 
 end, upon the l)road side or on the edge, as well as with reference to the 
 micropyle, adjoining it, at the ()])posit(> end or at some intermediate 
 ])oint. It is the last-mentioned character which detennines the class 
 of seed as to itstr()])ism (see Ovule). In size the liiluni may b(> a slight 
 point, or it may cover a considerable jjortion t)f the surface. Its form is 
 frequently characteristic, as heart-shaped (Fig. '.M()) or lim-ar and 
 channelled, as in Fig. '.Vi\. Its color fre(iuenlly (lifV(>rs markedly from 
 that of the remainder of the seed. 
 
130 
 
 THE SEED 
 
 The Raphe. — The raphe, extending from the hihim to tlie chalaza 
 when these do not coincide, is ordinarily not readily perceptible upon 
 the surface. When it is so, as in Figs. 372 and 373, its appearance is of 
 great diagnostic value and must be closely scrutinized. The chalaza 
 in its simple form calls for lio special attention. 
 
 The Strophiole. — If, however, an enlargement appears at this point 
 (the Stroyliiole, Fig. 374, a), it must not be overlooked. The strophiole 
 may develop into the arillus (Fig. 375), a partial or complete covering, 
 and its characters call for the same attention which is requisite for the 
 testa. 
 
 JM <^^J 
 
 Fig. 369. Vertical section, seed of Cardamomum. 370. Cordate hihiin, of Cardiospermum. 371. 
 Linear hilum of Calabar bean. 372. Central hilum of nux vomica. 373. Seed of Niederlinia with 
 conspicuous raphe and funiculus. 374. Seed of Hypericum with large strophiole at a. 375. Seed of 
 Hanetic with partial arillus. 376. Pitted seed of Sanvegesia. 377. Reticulate seed of henbane. 378 . 
 Reticulate-pitted seed of tobacco. 379. Finely reticulated seed of Datura. 380. Seed of Ricinus, 
 with caruncle at a. 381. Arilled seed of Myrislica. 382. Seed of Acorus, with peculiarly appendaged 
 micropyle. 
 
 The Testa. — The testa is not wanting in any medicinal seed. In 
 general it is not closely adherent to the underlying tissue, and it can 
 be readily removed. In its thickness, consistency, surface, color and 
 appendages it yields important pharmacognostical characters. It may 
 be pitted (Fig. 370), reticulate (Fig. 377), reticulate-pitted (Fig. 378) 
 or hairy (Fig. 372), and the minute characters of its pits, tubercles, 
 ridges, or hairs must not be overlooked. It may be dull or shiny, and 
 its color may be uniform or variegated (Fig. 379). Its luster or shade 
 of color is frequently of the greatest assistance in determining the age, 
 freshness, mode of preparing or preserving, or other conditions on which 
 the comparative medicinal quality of the seed depends. 
 
THE TEGMEN 
 
 131 
 
 The Caruncle.- Tlu> ('iil;ir<;eiiu'iit at the iiiicr()])yle (tlic Canmcle, 
 Fig. 380, a) calls for the same scrutiny as the str()i)hiole. It may be 
 variously api)eM(la<j;ed (Fig. 382), and, like the latter, it may extend 
 into a partial or com})letc covering, the arillode. The arillus, or arillode 
 (Fig. 381), may he i)artial, as in nutmeg, or complete, as in the seed of 
 the Euonymus. 
 
 Appendages. — Appendages to the seed do not always take the form 
 of an aril of either class, nor is their origin confined to the points from 
 which the aril devel()i)s. Fither as aril or ai)i)endage from the general 
 surface, they exliibit a great variety of form, of equal importance with 
 
 ,.« 
 
 
 383. 
 
 '''' iy?,si ^^ 
 
 J94. '^os. jm. 
 
 -Wl 
 
 JUO. 
 
 JM 
 
 Fig. 383. Seed of Eiicharidiiim, with fringed margin. 384. Penicillate seed of Epilobium. 385. 
 Tufted seed of Pelrocoptis. 386. Finibriate-winged seed of Daitais. 387. Winged seed of Cinchona. 
 388. Pluniose-awned seed of Stroiihanthus. 389. A globose seed. 390. Lenticular seed of Lens. 
 391. Saucer-shaped seed of Lecanosperma. 392. Linear seed of Nepenthes. 393. A polyhedral seed 
 of Nolina. 394. Serrated seed of Akebia. 395. Reniforni seed of bean. 39G. Cochlear seed of Ilelio- 
 chnris. 397. Crescent-shaped seed of Menispermum. 398. A lobed seed. 399. Nutmeg, with the 
 albumin niniinutcd. 
 
 those which characterize the pericarp. Forms of especially frequent 
 occurrence are exhibited by Figs. 383 to 388. Important distinctions 
 sometimes exist between seeds bearing similar ai)])endages, as regards 
 the j)oints from which the latter originate, as in the case of strojihanthus, 
 false and true. 
 
 The general form of the testa is, of course, that of the seed, and calls 
 for terms applicable to the forms of solid bodies (Figs. 389 to 398). 
 
 The Tegmen. — The tegmen, when present, is extremely thin and tightly 
 adiierent to the nucellus, following closely all inequalities upon the 
 surface of the latter, and occasionally having its intruded folds caught 
 between the forming masses of the albumin and discernible upon 
 
132 
 
 THE SEED 
 
 section of the latter as slender veins, giving us the so-called Ruminated 
 Albumin (Fig. :599). 
 
 The Albumin. — The albumin is characterized chiefly by its con- 
 sistency, being bony, as in the ivory nut and date; horny, as in nux 
 vomica; oily, as in the castor-bean and cacao; fleshy, mealy, etc. In 
 sectioning the seed, note should be taken of the presence, number, 
 position and forms of any cavities which may exist in it. 
 
 The Embryo. — The embryo calls for the most thorough and minute 
 study as a basis for systematic work, though for the pharmacognosist 
 only the more important details of its general structure need be con- 
 sidered. It has already been stated that it consists of one or more 
 phytomers. 
 
 4U2 
 
 Fig. 400. Circinate embryo of Campoma^H'.sfVi: /(, radicle; ca, caulicle- fo<, cotyledons. 401. Section 
 through seed of Gynocardia. 402. Centric curved embryo of Gynocramhe. 403. Centric straight embryo 
 of Frankeaia. 404. Germinating monocotyledonous embryo. 405. Embryo of Dipteryx with pinnatifid 
 plumule (pO- 406. Polycotyledonous embryo. 
 
 The Caulicle. — The chain of cells first formed is the pro-embryo, and 
 this is supposed to act in transferring nourishment to the embryo. 
 At its end, next to the cotyledons, develops the first internode of the 
 coming plant, and this becomes the caulicle (m in Figs. 400 to 403), 
 in old works denominated the "radicle." 
 
POSITION OF THE EMBRYO 133 
 
 The Radicle. — ^Tlie Radicle (// in the last-iianu-d (i<,nircs) is tlie extreme 
 tip of the cauliele, which points always in the direction of the micropyle. 
 From this i)()int the root is to be developed. The embryo may consist 
 of nothing fnrther than the cauliele, and even this may be of the most 
 elementary character. 
 
 The Cotyledons. — Ordinarily, however, there develops at the node 
 (tiie point opposite to the radicle) one or more Cotyledons, or Seed- 
 leaves {cot in the figures). 
 
 Monocotyledons, Dicotyledons, and Polycotyledons. — Most seeds which 
 possess but a single cotyledon (Fig. 404) are grouped together in a 
 division of the Angiosperms, which for this reason are called Mono- 
 cotyledons, those with two in the Dicotyledons. A few plants, mo.stly 
 Gymnosperms, are ])()lyc()tyledons (Fig. 406). 
 
 The Plumule. — The highest plants of their respective groups develop 
 a second phytomer lying between the cotyledons, or if there be but one 
 cotyledon, mostly enwrapped by it. This is the Plumule (Fig. 405, jjI), 
 which shows the same variation in the degree of its development as 
 that which characterizes the lower. When its leaves are developed, 
 they bear a closer resemblance, as in the figure, to the mature leaves 
 of the plant than do the cotyledons, following out the law referred to in 
 our introduction. Among dicotyledons, the ])lumulc commonly pertains 
 to exalbuminous seeds. 
 
 Direction of the Radicle. — Terms used to indicate dirt'erent directions 
 of the radicle refer to its direction with relation to the fruit, its direction 
 in relation to the micropyle being, as has been stated, always the same. 
 It is Ascending when it points toward the apex of the fruit. Descending 
 when in the opposite direction, and Horizontal when intermediate. 
 The latter form is Centrifugal when pointing toward the perii)hery, 
 Centripetal when toward the axis. 
 
 Position of the Embryo. — The position of the embryo with reference 
 to the albumin is always highly cliaracteristic. It is Axile or Centric 
 when in the center of the albumin (Figs. 402 and 403), whether straight 
 or curved; Eccentric when within the albumin, but outside of its center 
 (Fig. 407); Peripheral when 1\ ing upon the surface of the albumin. In 
 the latter position it may be straight, sim])ly cur\ed (Fig. 4()S\ or 
 circinately coiletl (Figs. 409 and 410). 
 
 The relative sizes of the embryo and the albumin vary from those 
 in which the former is a mere sjjeck in a large mass of the latter to that 
 in which the proi)ortions are reversed, or in which the ;iil)uniin is 
 entirely wanting. 
 
134 
 
 THE SEED 
 
 Forms of the Embryo. — The eml)ryo should in all cases be dissected 
 from the contiguous parts and the relations of its parts to one another 
 made out. It may be straight, variously curved, crumpled (Fig. 411), 
 or variously folded. In the latter condition the radicle may be brought 
 into juxtaposition with the edges of the cotyledons (Accumbent, Fig. 
 413) or with the face of one of them (Incumbent, Fig. 412), One 
 cotyledon may enwrap the other (Fig. 414). When a single cotyledon 
 partly encloses the greater portion of the remainder of the embryo 
 it is sometimes called the Scutellum (Fig. 415). Some of the terms 
 applicable to the consistency of the albumin are also applicable to that 
 of the cotvledons. 
 
 Fig. 407. Eccentric curved embryo of Galium. 408. Peripheral simply curved embryo of Bosia. 409. 
 Peripheral circinately curved embryo of ^cAj/raniAes. 410. Circinately coiled embrj'o. 411. Crumpled 
 embryo of Suaeda. 412. Incumbent radicle of Calepina. 413. Accumbent radicle of Megacarpaea. 
 414. Embryo of Dryobolanops, one cotyledon enwrapping the others. 415. Embryo of barley with 
 scutellum (s). 
 
 The Taste. — Finally, the pharmacognosist will find it of importance 
 in the case of seeds possessing a characteristic taste to inform himself 
 as to the part, if any, to which such taste is restricted. 
 
 Reproduction Completed. — With the production of the seed, containing 
 a distinct living individual separated from the parent and fitted for 
 independent existence, reproduction can strictly be considered as com- 
 pleted, although the progeny is still in its infancy and its form not yet 
 perfect. 
 
 Similarity of the Seed to the Bud. — The analogy between the seed and 
 the bud is apparent. Each consists of one or more vegetative units 
 ready to develop under proper conditions into a perfect semblance of 
 the parent, and each is provided with a store of prepared nourishment 
 
EXAMINATION OF THE SEED 135 
 
 to sustain it until able to manufacture such for itself. The distinction is 
 in the radically different modes of origin, and in structure, leading to 
 different powers of reproduction. 
 
 Examination of the Seed. — ^In the examination of the seed for the 
 determination of the {'haracters above defined, the most certain method 
 is the examination of transverse and longitudinal sections by the use 
 of the compound microscope, as will be explained in Part II of this 
 work. It is not difficult, however, to determine all the essential char- 
 acters of most seeds by the aid of an ordinary magnifying glass. The 
 superficial characters of the seed should first be examined in the dry 
 condition, after which it should be thoroughly soaked for a period 
 varying from a few hours to several days, or the preparation may be 
 hastened by gently boiling. Its superficial characters must be then 
 again examined and compared with those previously observed. Espe- 
 cially must the relative positions of chalaza, hilum, micropyle, and raphe 
 be accurately determined. A longitudinal incision is then to be made 
 along one side and the coats removed, separately if possible. The 
 examination of the testa, with the discovery of a much thickened line, 
 will sometimes disclose a raphe which was overlooked in the superficial 
 examination. In removing the coats, great care must be taken to avoid 
 wounding the nucellus. The position of the embryo with regard to the 
 albumin, if any, and its general form can now be readily ascertained. 
 The embryo should finally be removed and its several parts studied. 
 The most common error made by students is the mistaking of small 
 one-seeded fruits, such as mericari)s, akenes, and nuculae, for seeds, with 
 the result that all of the parts and their relations are confused. The 
 substitution of such terms as conium-fruit, coriander-fruit, burdock- 
 fruit, and hem])-fniit for the incorrect terms "Conium-seed," etc., in 
 common use, should be encouraged by all educated i)harmacists in 
 their daily business relations, as a correct idea of the natiu'e of the jiarts 
 employed lies at the foundation of a proper understanding of their 
 composition and i)r()j)crties. 
 
CHAPTER XIII 
 GENERAL STRUCTURE OF ROOT AND STEM 
 
 The Development of Different Tissues. — The de\'e]opment of the stem 
 commences with the formation of the embryo, by the process explained 
 at the beginning of our study of the seed. So long as the cells produced 
 by this process are the same in kind, the body consists of but one tissue; 
 but through differentiation and specialization among them, difi'erent 
 tissues are soon developed. 
 
 Meristem. — The power of cell-di\'ision and growth is lost by most 
 tissue after a time, while in other parts it persists permanently. Any 
 tissue or portion of tissue which possesses such power is called Meristem. 
 Tissue may cease finally to exert meristematic power, or it may resume 
 such power after a time. All meristematic processes cease upon maturity 
 of seed, recommencing with germination. 
 
 Degree of Development Attained by the Embryo in the Seed-condition. — 
 The point reached in the development of any plant-body in the embry- 
 onic condition — that is, at the maturity of the seed — does not depend 
 in any degree upon the amount or kind of tissue or tissues developed, 
 but altogether upon the habit of the particular class of plant. In some 
 embryos, tissue differentiation cannot be seen to have taken place at 
 the time of separation from the parent, while in others it has progressed 
 very far, though never (unless germination has occurred) to the pro- 
 duction of a true root. It is impossible, therefore, to fix upon any 
 particular developmental stage of stem-structure as distinguishing the 
 ungerminated embryo from the germinated plantlet. In the following 
 sketch of its development, then, no note is taken of the resting period 
 in the seed-stage, but the process is followed as though it were con- 
 tinuous from fertilization through germination and into the mature 
 condition of the plant. 
 
 Although of primary importance scientifically, and of great interest, 
 the phenomena of germination are not important from the standpoint 
 of pharmacognosy, and a mere outline of them is here given. 
 
 Vitality of Seeds. — Animation is probably not entirely suspended 
 during the resting period of the seed. That is, there is an apparent 
 
GERMINA TION 
 
 137 
 
 iiitorc-luin<,^o of substance, due to vital action, hetweeu the seed and the 
 surrounding atmosphere, altliough c\treniel\' shght, so long as the former 
 possesses its vitality. 
 
 The evidence as to h-ngtii of time (hiring wliich seeds can retain their 
 vitaHty is extremely contradictory, and the greatest diversity of oj)inion 
 exists concerning this point. Our best authorities bclicxc that we have 
 no conclusive e\'idciic(> that the period is longer than about fifty years, 
 although, u])on the other hand, we have no positive evidence that it is 
 not ver\' nuich Jouiicr. 
 
 Germination. — ('oiidifions of (IcnnliKifioii.- (u-rniination dciiends 
 u])on (Da specific temperature, varying for seeds of dillerent species 
 and for those of the same species when they hav(> become" habituated 
 
138 GENERAL STRUCTURE OF ROOT AND STEM 
 
 to essentially different climatic conditions; (2) a specific saturation, also 
 varying with different seeds — that is, the absorption of an amount of 
 water bearing a fixed ratio to the weight of the seed : (3) a partially fixed 
 degree of light exclusion; (4) the presence of free oxygen. 
 
 The Process of Germination. — Under these conditions, ready prepared 
 nutriment is dissolved, other forms become digested by special vegetable 
 ferments (Enzymes) present, heat is developed, cell-propagation and 
 cell-growth take place, and the development and growth of a plant from 
 the embryo commence. By the growth of the embryo, the radicle is pro- 
 truded through the micropyle, the rest of the body soon following and 
 leaving the embryo free from its coats, or the body may remain enclosed 
 in the coats for some time. The» radicle, if it does not already point 
 directly downward, turns in that direction and develops into a root 
 (Figs. 417 and 419). The cotyledons may then separate completely, 
 leaving the plumule or second phytomer to develop from the apex, 
 between them (Fig. 416), or the cotyledons may remain in contact, and 
 the plumule or second phytomer burst forth from between the bases 
 of their petioles (Fig. 418). The end of the embryo opposite to the 
 radicle, if it does not already point upward, turns in that direction and 
 develops as the apex of the stem. 
 
 The Epicotyl and Hypocotyl. — The stem above the cotyledons is called 
 the Epicotyl, that below them the Hypocotyl. 
 
 Cellular Development and Growth. — The cellular nature of develop- 
 ment and growth demands a general knowledge of histology for their 
 understanding, so that we shall here consider, so far as possible, only 
 the gross results of the processes, or such characters of the root and 
 stem as can be demonstrated by other than histological methods. Such 
 references to cellular structure as are here necessary are given rather 
 figuratively than technically. The mode of growth in root and stem, 
 and the structures resulting, are sufficienti}' different to require separate 
 treatment. Although the forms of structure liere considered as applying 
 to the root concern only flowering plants and the very highest of the 
 cryptograms, yet the description is applicable to all roots used in 
 medicine. 
 
 Structure of the Root. — Upon examining a transverse section of the 
 root in its rudimentary condition, it is possible to distinguish three 
 bodies of tissue exhibiting characteristic differences in their cellular 
 elements (P'ig. 420). 
 
 The Plerom, Pleriblem, and Dermatogen. — The central portion is 
 occupied by a solid cylinder called the Plerom (a). Outside of this 
 
STRUCTURES DEVELOPED FROM THE PERIBLEM 
 
 139 
 
 there is a hollow cylinder called the Periblem (6), and still outside of 
 this and upon the surface of the root a second hollow cylinder, the 
 Dermatogen (c). 
 
 Structures Developed from the Dermatogen. — The last mentioned 
 develops a primary covorhig called the Ki)i(k'rmis (Fig. 422, a). 
 
 The Root-cap. — The ci)idermis consists in its earliest stage, and there- 
 fore at the very tip, of a number of layers of cells which protect the 
 apical growing point of the root, and is therefore called at that point 
 the Root-cap (Fig. 41 G, a-b). Toward the summit of the root-cap the 
 outer layers of cells successively wear off or are cast off, so that 
 the epidermis becomes reduced to a single thickness of cells. 
 
 Fig. 420. Diagram illustrating arrangement of ground-tissues of root: a, plerom; b, periblem: c, 
 dermatogen. 421. Plerom enclosed by endodermis (c), with first appearance of bundles: e, xylem- 
 bundle; /, phloem-bundle; g, medullary-raj- : h, pericycle; i, temporary pith. 422. The same in 
 a more advanced stage, the outer portions also present: a, epiderm; b, liypoderm; c, endodcrm (cortex 
 between b and c); e, xylcm-bundles now meeting at center; /, phloem-bundle; (?, medullary-ray; h, 
 pericycle; i, cambium of the primary phloem-bundle; y, of the primary xylem-bundle; 2, of the 
 primary medullary-ray. 
 
 The Ruot-hdirs and Pclij'croiis Layer.- — Here it frequently (lc\clops a 
 dense covering of Root-hairs which adhere tenaciously to the soil and 
 perform various processes connected with absorptit)n (Fig. 410, h-c). 
 For this reason, this portion of the epidermis of the root is known 
 as the Piliferous Layer. 
 
 The Epidermis Proper. — Still farther uj) these hairs have fallen 
 away, and the single layer, after slight modifications, becomes converted 
 into the epidermis i)roper. This has a variable duration in difl'erent 
 plants and is consequently found covering the root for a greater or less 
 distance upward. Almost always its duration is very short. It either 
 disappears altogether, being replaced by a structure (Periderm) devel- 
 ()])c<l from the periblem, or in rare cases itself develops into the periderm. 
 
 Structures Developed from the Periblem. — The periblem of the root 
 develops into the Cortex (Fig. 422 between b and r), consisting of a 
 number, often a large number, of layers of cells. 
 
140 GENERAL STRUCTURE OF ROOT AND STEM 
 
 The Ilypodermis. — Its outermost portion, usually of one layer of 
 cells, presents a different appearance from the subjacent layers, and 
 is the Hypodermis (Fig. 422, h) in the case of the root becoming the 
 Exodermis. The hypoderm lies against the inner face of the epiderm 
 (a), while that persists, l)ecoming afterward the superficial layer, and 
 persists for a longer or shorter period. Its characteristics are of great 
 importance in histological determinations. 
 
 The Endodermis. — The innermost layer of the primary cortex is even 
 more distinct in appearance than the hypoderm, and is the Endodermis 
 (c). It lies in contact with the outer surface of the structure developed 
 from the plerom. 
 
 Disappearance of the Primary Cortex. — The production of primary 
 cortex is quickly completed. If then the growth inside of it continues 
 indefinitely it, in most plants, involves the destruction and disappearance 
 of the primary cortex, which must be replaced by some other covering. 
 
 Promsion by Phellogen for a New 'Covering. — A new meristematic 
 region must then be established for the purpose of manufacturing such 
 a covering. This almost always arises in some part, and it may be in any 
 part, of the primary cortex. It is the Phellogen (Fig. 422, d). The 
 phellogen may be in the form of a continuous circle or the usual form 
 in that of blades or plates (d), variously placed and directed. 
 
 Periderm and PheUoderm. — Upon its outer surface the phellogen 
 develops corky tissue, the Periderm, and upon its inner a secondary 
 cortex, the PheUoderm. Occasionally it will produce only periderm or 
 only phelloderm. 
 
 Secondary Periderm. — As the periderm becomes impervious to the 
 nourishing fluids, it and all the tissues exterior to it must die, and may 
 be cast off, a new phellogen then appearing farther toward the interior 
 to form a new periderm, so that we may have successive periderms — 
 the primary, secondary, and so on. This process is comparatively' rare 
 in the case of the root, very common in that of the stem. 
 
 The Bork. — In such cases, the corky layers which become successively 
 superficial, observed in the scales of bark which peel off from tree-trunks, 
 constitute the Bork or Rhytidoma. Bork is called Ring-bork when it 
 forms a cylinder, Scale-bork when it occurs in detached plates. It must 
 be noted that the origin of the bork, and, as will be shown later, its 
 structural nature dependent thereon, will depend upon the depth at 
 which the phellogen develops. The same feature will also determine the 
 amount and character of the tissue, if any, existing between it and the 
 structure developed from the plerom. 
 
STRUCTURES DEVELOPED FROM THE rJ.EROM 141 
 
 No Fibro-mscular TLs-suc Developed j'roin Perihieiii.— Su tissue 
 developed directly or indirectly from the j)eril)lein is in the form of 
 distinct and rej^ular bundles of vessels, though irregular and isolated 
 or anastomosinti tubes are frequently develojjed by it. 
 
 Structures Developed from the Plerom. The S1ele.~ The essential 
 characteristic of the body developed from the plerom of the root is 
 that it is invested by the endodermis and is free from any other endo- 
 dermal development in any part. It, therefore, constitutes a Stele 
 (all inside of c), which in the root is always in the form of a Central 
 Cylinder. 
 
 Differentiation in the Cells of the »S7t7f'.— The plerom exhibits at first 
 only sHght differences in the appearance of its cells (Fig. 420, a), and 
 a transverse section of it viewed with the microscope might be figura- 
 tively compared to looking down upon a honeycomb built in a cylin- 
 drical tin box, the latter representing the endodermis, and in longitudinal 
 section to a longitudinal section through the same. This constitutes 
 the Ground-tissue of the Stele. Farther away from the tip, however, 
 it would be found that groups of its cells (Fig. 421, e and/) had elon- 
 gated in a longitudinal direction, and these, to continue our illustration, 
 might be compared to bundles of pencils or quills set in the honeycomb. 
 Mingled among the elongated cells of the bundle, however, are many 
 which have not elongated. 
 
 Medullary Rai/.'i. — These bundles would be arranged in a circle 
 separated from one another })y more or less of the honeycomb tissue, 
 these sej)arating ])ortions corres])()nding to the Medullary Jvays of the 
 Stele (g). 
 
 The Pcriri/cle. — From the endodermis they would be separated by 
 one or more continuous circles of the honeycomb cells, corresponding 
 to the Pericyde or " Pericambium" (h). For a time there would also 
 be left a central jiortion (/), consisting of unchanged cells, forming a 
 temporary Medulla or pith. 
 
 The Vessels. — The elongated cells, which constitute the imj^ortant 
 elements of the bundles, are joined end to end with other similar ones 
 still farther uj) in the older jKirt of the structure. At first the enii walls 
 of these abutting cells sei)arate their cavities from one another, but 
 later these disappear in those of some bundles, becoming jjcrforatcd in 
 those of others, so that the cavities become more oi- less contiinious, 
 forming the Vessels, extending throughout the root and intoaiul through 
 the stem above. The bundles thus formed are thus of two kinds, aher- 
 nating in the circle. 
 
142 GENERAL STRUCTURE OF ROOT AND STEM 
 
 The Xylem- or Wood-bundles. — Each of those of one kind (Fig, 422, e) 
 extends gradually toward the center by the successive development 
 there of vessels or cells associated with the vessels of the bundles. Upon 
 meeting there, the bundles, of course, cut off the previously existing 
 central communication between the medullary rays, which are now left 
 as isolated plates or wedges between the bundles, the temporary pith 
 being thus obliterated. These bundles, which meet at the center, are 
 known as the Xylem-bundles or Wood-bundles, and constitute the 
 wood}' portion of the root. 
 
 The Ducts. — The tubes formed as described above are the Ducts. 
 In a few plants which we have to consider, the Gymnosperms, no 
 series of cells lose their end-walls as above described so as to become 
 converted into continuous tubes or ducts, though they connect by 
 perforations. 
 
 The Phloem- or Sieve-bundles and Sieve-tubes. — The other bundles 
 (Fig. 422, /) which have been described as alternating with the xylem-, 
 or wood-bundles, possess as their important element those cells which 
 become connected by perforations in the form of sieves, and are known 
 as the Phloem-bundles. 
 
 Collectively they form what is known as the Sieve-tissue, or Cribrose- 
 tissue, of the plant, and their intercommunicating tubes are the Sieve- 
 tubes. This tissue characterizes the Gymnosperms as well as the 
 Angiosperms. The phloem-bundles do not extend toward the center, as 
 do the xylem-bundles, but stand isolated, each between two medullary 
 rays, which respectively separate it from the xylem-bundle upon either 
 side. 
 
 The Fibers. — In connection with the ducts, or their equivalents 
 in the gymnosperms, and the other tissues of the xylem-bundles, strong 
 fibers develop, the Wood-fibers, while in connection with the sieve-tubes 
 and other tissue of the phfoem-bundles very similar fibers, the Bast- 
 fibers, usually develop. The phloem-bundles, therefore, ordinarily 
 become Bast-bundles. 
 
 Fibro-vascular Bundles. — Vascular bundles in which fibers develop 
 are known as Fibro-vascular bundles. 
 
 Secondary Groivth of the Stele. — The condition now reached by the 
 root constitutes the completed primary structure of its stele. The 
 student should not fail to note that the primary structure refers only 
 to the very smallest roots, and that he need not expect to encounter it 
 in any roots in a condition to be used medicinally. His examination 
 of roots in Pharmacognosy will, therefore, relate to the secondary 
 
CONTINUOUS MULTIPLICATION OF THE STRUCTURES 143 
 
 structure, an account of wliich will follow. With the production of the 
 primary structure, growth and increase in thickness may cease (most 
 ]\Ionoc()tyledons), in which case the periderm changes which we have 
 recorded will not occur. On the other hand, secondary growth may 
 take place, in which case those changes are more or less completely 
 induced. 
 
 Development of the Cambium. — In such case, the cells touching the 
 phloem-bundles upon their inner faces and n])on their sides become 
 meristematic and proceed to produce xylem-tissue upon their inner 
 faces and secondary phloem upon their outer, in contact with the 
 primary tissue of that kind. Each such arc of meristem (Fig. 422, x) 
 becomes the Cambium of that bundle. 
 
 Completion of the Bundles. — At the same time the cells lying in contact 
 with the outer surfaces and with the sides of each xylem-bundle similarly 
 become a cambium for that bundle {y), and sometimes produce second- 
 ary xylem, upon their inner faces, in contact with the primary xylem 
 there, and secondary phloem.upon their outer faces. By these processes 
 each bundle which undergoes them, previously consisting of one kind 
 of tissue, therefore an incomplete bundle, comes to consist of both kinds 
 of tissue and becomes a complete bundle. 
 
 The Cambium-circle. — Connecting the cambium arcs of the adjacent 
 bundles, a cambium arc (2) forms in the intervening medullary ray, and 
 this produces secondary medullary ray tissue on both its inner and its 
 outer face. There is thus formed a continuous cylinder of cambium 
 (.r, y, z), though a somewhat irregular and wavy cylinder, standing 
 between the zone formed within by the primary and secondary xylem- 
 bundles and their intervening portions of the medullary rays, and the 
 outer primary and secondary phloem-bundles (when the latter develop) 
 with their intervening portions of the medullary rays. Although this 
 cambium forms a cylinder, as stated, it is usually referred to as the 
 " Cambium-ring," or " Cambium-circle," because it presents this appear- 
 ance in transverse section. 
 
 Continuous Multiplication of the Structures. — Provision is now nuule 
 for the growth of all portions of the stele. Additional complete fibro- 
 vascular bundles are now developed in the medullary ray spaces between 
 the others, fed by a portion of cam])ium in a similar manner. New 
 medullary rays also develop in the substance of the bundles. We thus 
 have developed upon the inside of the cambium-cylinder a cylinder of 
 xylem, solid except for the blades of medullary ray tissue ])enetrating 
 it nearlv to the center, and outside of the cambium-cvlinder a hollow 
 
144 GENERAL STRUCTURE OF ROOT AND STEM 
 
 cylinder of phloem tissue or bast tissue, continuous except for similar, 
 but of course much shorter, medullary rays. 
 
 It has been said above that the portions of the cambium-circle 
 opposite to the primary wood-bundles "may" produce secondary 
 wood upon their inner faces and secondary phloem upon their outer. 
 While this does take place in some roots, it usually does not, only 
 pericycle tissue forming at those points on both the inner and outer 
 faces of the cambium. 
 
 The above constitutes the secondary structure of the root-stele, and 
 any further growth which may occur, except for the development of 
 branches, considered hereafter, is merely a continuation of the process 
 described as secondary growth. 
 
 The Annual Rings. — When an annua! resting-period in growth occurs, 
 the ducts of the xylem produced toward the close of the year's growth 
 will be conspicuously smaller than those produced at the beginning, so 
 that conspicuous Annual rings are produced in many woods. 
 
 The Duramen and Alburnum. — ^After a tree has attained a certain age, 
 the wood at the center dies, and becomes dryer and harder and of a 
 different color from the living wood outside of it, and this dead portion 
 becomes thicker year by year. It is called the Duramen, or "Heart- 
 wood," and it often contains medicinal or coloring matters. The outer 
 is called the Alburnum, or "Sap-wood." It is the duramen only which 
 yields the most of our colored cabinet lumbers. 
 
 Effects of Secondary Growth upon the Superficial Structure. — The 
 effect of secondary growth upon the structures external to the bast- 
 cylinder is extremely variable, according to the extent of such growth 
 and the relations of the phellogen and its structure and the individual 
 habit of the plant. It has been stated that the phellogen may develop 
 in any part of the cortex. It may now be stated that it may, and, in 
 fact, usually does, in the root develop in the bast-cylinder itself, so 
 that all the parts external to it, and even portions of itself, will belong 
 to the periderm, or in the rare case of Bork-casting by the root, will 
 be cast off. 
 
 Origin of the Branches of the Root. — In all the classes which yield our 
 medicinal roots, the branches start from the pericycle outside of a 
 xylem-bundle at the point h (Fig. 421), as it is first developing, and grows 
 through the surrounding tissue to and from the surface. If cross- 
 sections have been cut through a root so as to pass through its branches 
 also, the branches on the older part will appear as mature secondary 
 roots. Those lower down will be successively less developed, appearing 
 
STRUCTURE OF STEM AS COXTRASTE /) WITH Til A T OF ROOT 145 
 
 at ItMifftli uj)()n the younger })()rti()n as not yet having made tlieir way 
 througli the overlying tissues to the surface. As the root first formed 
 is called the Primary, so its l)ranches are called Secondary. 'J'heir 
 structural develoi)ment is a rejx'tition of that of the ])rimary. 
 
 Continuity of Root-growth.- The continuity of growth in the root is 
 uniform — that is, there is no di\ision of it into joiuts or ])hytomers. 
 There are hence no regular distances at which it hranclus, and when 
 buds are produced ui)on it, as they are in rare cases, their points of 
 origin are not so regulated. 
 
 Structure of the Stem as Contrasted with that of the Root. — (The follow- 
 ing account of stem-structure refers only to the ordinary i)lants of the 
 flowering class. At its close a brief reference will be made to such others 
 as require attention for the pur])()ses of ])harmacognosy.) 
 
 The history of stem-devel()j)ment is best presented by contrasting it 
 with that of the root, which has already been given. The three elemen- 
 tary tissues, dermatogen, periblem, and plerom, are also found in the 
 young stem-structure. The epidermis and other tissues of the stem are 
 more variable than the corresj)onding tissues of the root, and the details 
 l)ertain for the most i)art to histology and to the special treatment of 
 species or groups. 
 
 The Epidermis. — The most im])ortant distinction between the ej)i- 
 dermis of root and stem may be mentioned as the i)resence in the latter 
 of stomata, to be studied in connection with the leaf. There is no 
 extra development from the dermatogen at the tij) corresi)onding to 
 the root-cap, nor of hairs similarly aggregated to those of the root, 
 although hairs of many forms abound upon the epidermis of the stem. 
 Stem-epidermis may consist of one or of several layers, and if the latter, 
 they may l)e dissimilar in varying degrees. Rarely it is i)ersistent, 
 being usually thrown off through the growth of the parts within it, 
 as has already been considered in the case of the root. 
 
 The Cortex. — The i)eril)lem of the stem develops structures in general 
 similar to thos(> of the root-pcM-ibU^n, the most imj^ortant distinction 
 being the ])r()(lucti(in of a (■hloro])hyll-hiyer. A ])riniai"y cortex, usually 
 somewhat thinner than that of the root of the same i)lant, is bounded 
 externally by a hypoderm and internally by an endoderm, and may 
 de\-elo]) tubes similar to tlio-e mentioned as fre(iiientl\- ])ei-taining to 
 the root-cortex, but, as in that case, no true \a>cular bundles. The 
 effects of growth within the ])rimary cortex of the root, leading to the 
 formation and casting off of bork, we h;t\e seen to be of rare occurrence. 
 In the case of the stem, howc\er, it is of \ cry general occurrence, so 
 10 
 
146 GENERAL STRUCTURE OF ROOT AND STEM 
 
 that the entire account which has been given of the development and 
 disposition of periderm and phelloderm may be appKed with special 
 force in the case of the stem. 
 
 The Central Cylinder. — The principal differences between root- 
 structure and stem-structure are found in the de^'elopments from the 
 plerom. Although, with the single exception, among important medi- 
 cinal stems, of the male fern, there is but a single stele, in the form 
 of a central cylinder, yet the development of its structure is markedly 
 different from that of the root. Leaving out of consideration exceptions 
 which are unimportant in pharmacognosy, we find that two distinct 
 types, of structure characterize respectively the monocotyledons and the 
 dicotyledons and gymnosperms. The form characterizing the latter 
 two will be first considered. 
 
 TJie Primary Bundles. — Vascular bundles originate in the plerom in 
 the form of a circle, just as in the case of the root, the important differ- 
 ence being that each bundle consists, even in its primary state, of both 
 phloem and xylem, with a cambium between. 
 
 The Open Collateral Bundle. — The typical form is that which in the 
 root constitutes the secondary structure — namely, a bundle consisting 
 of xylem within and phloem without the cambium arc, and this con- 
 stitutes what is known as the Open Collateral Bundle. 
 
 Secondary Growth. — Secondary growth here consists in the addition 
 by the cambium to each kind of tissue, and, in almost all cases, the 
 development of new intermediate bundles and new medullar}^ rays, 
 as has been described in the case of the root. The result is that the 
 general plan of structure attained is identical with that already recorded 
 as ultimately attained by the most highly developed woody roots. 
 There are, however, several differences which must be noticed. 
 
 The Medulla or Pith. — The most important is that the primary 
 xylem-bundles do not progress toward and meet one another at the 
 center, so that there is always left there a cylinder of the fundamental 
 tissue, constituting the ^Medulla or Pith, which is connected through 
 the primary medullary rays with the pericycle, or, after the disappear- 
 ance of that and of the endodermis, with the cortex. 
 
 The whole structure in transverse section may now be roughly com- 
 pared with the wheel of a wagon. The pith corresponds to the hub, 
 the primary medullary rays to the spokes, the spaces between the 
 spokes to the primary wood wedges, the felloe to the bast product, 
 except that the spokes should be seen extending through it, and the 
 tire to the periderm in its various forms of development. 
 
DIRECTIONS OF SECTION I-SG FOR EXAMINATION 147 
 
 Variations in Structure.— Altliouj,^!) the details of tissue-arrangement 
 pertain to histology, yet the deviations from the above relative positions 
 of the phloem and xylem are of such very great importance in pharmac- 
 ognosy that they are here referred to. We may have (1) the Bieollateral 
 Bundle, in which a second fascicle of phloem is placed upon the inner 
 face of the xylem; (2) the peculiarities characterizing the monoco- 
 tyledons, which will be described later. 
 
 There are three ways in which the strncture of the root or stem may 
 be examined. 
 
 Directions of Sectioning for Examination. — 1. A Radial section is a 
 longitudinal section in a plane passing through the center. 
 
 2. A Tangential section is a longitudinal section in a ])lanc which 
 does not pass through the center. 
 
 \\. A Transverse section is one i)assing exactly at right angles to 
 the former two. 
 
 Appearance of the Radial Section. — The appearance presented by a 
 radial section through a perfectly developed woody stem possessing 
 open collateral btmdles may now be described as follows, enumerating 
 the structures upon either side from the center outward: (1) Pith; 
 (2) wood wedges, with medullary rays, the latter, if primarj^, communi- 
 cating with the pith at the center and outward with the cortex; if 
 secondary, extending outward like the primary, but no farther inward 
 than the limit of the ring in which it originates; (3) the cambium; 
 (4) the bast bundles, separated by their medullary rays; (5) the phello- 
 derm, phellogen, and periderm, the relations of which to one another 
 and to the bast, and the structure of which, cannot be specified, owing 
 to the extreme variation which they dis])lay in different stems. The 
 composition of the bork, if any, will also depend upon the point of 
 development of the phellogen and its form upon the form of the latter. 
 
 Appearance of the Transterse Section. — Upon a transverse section, 
 the same structures as above recorded will appear, but instead of being 
 in the form of thin strips upon either side of the center, they will be in 
 the form of concentric rings around it. Thus the center is seen occupied 
 by a circle of pith, outside of which is a zone of xylem or wood tissue, 
 separated by longer or shorter medullary ra\s into its primary and 
 younger wood bundles. Outside of the first ainnial ring is where the 
 intermediate or secondary bundles make their first appearance. The 
 secondary medullary rays (Fig. 42)^, a) will be found not to extend 
 inward beyond the production of tissue of that year. Instead of appear- 
 ing as blades, as they did in the radial section (Fig. 42;>, b), the medullary 
 
148 
 
 GENERAL STRUCTURE OF ROOT AND STEM 
 
 rays now appear as narrow lines. That is, we now see the edges of the 
 blades whose sides were before seen. Passing outward beyond the 
 last of the annual rings, which successively exhibit a greater number of 
 wood-bundles and medullary rays, we reach the cambium-ring. Outside 
 of this we find the phloem or bast bundles sejjarated by medullary rays 
 continuous with those of the wood cylinder, and still outside of this the 
 periderm. 
 
 Fig. 423. Diagram illustrating section of woody portion of dicotyledonous stem: a, edges of medul- 
 lary rays as seen in transverse section; 6, sides of same as seen in radial section; c, ends as they would 
 appear in tangential section. 
 
 Appearance of the Tangential Section. — The appearance of a tangen- 
 tial section will depend, of course, upon the tissues through which it 
 passes. If it cuts the medullary rays these will appear neither as the 
 broad sides, as at h, nor the edges of blades, as at a, but as transverse 
 sections of them, as at c. If the ray consists of but one row of cells in 
 width, then such a row will be exhibited upon the tangential section, its 
 vertical height varying from a very few to quite a large number of cells. 
 If, upon the other hand, it possess a lateral breadth of several thick- 
 nesses of cells, of 5 in our figure, this condition will exist only at its 
 middle portion. At its upper and lower limits it will ordinarily be 
 reduced to the thickness of a single cell, so that the tangential aspect 
 of a medullary ray is almost always that of an ellipse, broad or narrow, 
 according to the numl)er of rows of cells of which it consists, in contrast 
 with the extent of its upward and downward extension. 
 
STRUCTURE OF THE MOXOCOTYLEDOXOUS STEM 119 
 
 Til sonic stems the ])illi oi' incdull.-i (lis;ii)|)c;irs more or less eom- 
 ])Ietely after a time, lea\in<j; a eyliiidrieal liollow cavity. This may he 
 eoiitiiiiious throii,y;h the nodes or sejjarated at those i)oiiits hy transverse 
 partitions. 
 
 Structure of the Monocotyledonous Stem. In monoeolyledons (Fij;. 
 4lM) \\(> ha\-e the Closed hnndle, in which the one element surrounds 
 and encloses the other. In all medicinal monocotyledonous stems 
 possessing such hundles, it is the xylem which encloses the phloem. If 
 the two cylinders thus formed have a common center, which form is 
 not very common, it is called a Concentric hnndle. It is clear that in 
 the last two forms a caml)inm cylinder, such as distinguishes the stele, 
 possessing the form i)revi()usly considered, cannot be formed. In such 
 
 Fig. 424. Transverse section of monocotyledonous stem: a, closed hundles scattered through paren- 
 chyma; 6, nucleus sheath, or cndodermis. 
 
 plants indefinite growth in thickness of the hundles ohviously cannot 
 occur, and the same is true of the entire stele, unless new hundles shall 
 develo]) in it. Usually this does not occur, hut if the ui)i)er portion of 
 the plant shall l)ranch and continue to extend its leafy surface, meristem 
 tissue will then form toward the outer i)ortion of the stele, and from 
 this new hundles will successively arise, so that the thickness of the 
 trunk will kee]) ])aee with the extension of the crown, notwithstanding 
 that the individual hundles do not increase in thickness after the com- 
 pletion of their primary structure. In stems i)ossessing this form of 
 hundles the latter (Fig. 424, a) are found more or less scattered through 
 the fundamental or medullary tissue, though there is commonly more 
 or less of a concentration of them in some one region, usually toward 
 the i)eriphery of the stele. 
 
150 GENERAL STRUCTURE OF ROOT AND STEM 
 
 The Nucleus-.^ heath. — The eiulodcnnis of such })hints is commonly 
 known as a Xucleus-sheath (6). 
 
 Polystelar Stems. — Finally, we note that in many plants, represented 
 among drugs by the ferns, the stem possesses a number, usually definite 
 for the species, of vascular bundles, or groups of them, each invested by 
 its own endodermis, each being thus a stele. Such stems are, therefore, 
 called Polystelar. In such plants no epidermis is developed, the 
 hypoderm, developed from the periblem, being superficial. 
 
 The Bark. — Its Nature. — The Bark is everything external to the 
 cambium. It has been proposed to remove the word "bark" from 
 common language, or to ignore its fixed common meaning, and to 
 convert it into a technical name for the bork. Experience with English- 
 speaking people leaves no hope that thej^ will consent to give up a word 
 employed so widelj' and in such important ways, and its technical use 
 can apparently result only in the introduction of a confusion, which is 
 more wisely avoided by the coining of some new' name, if that of bork 
 is seriously objectionable, which does not appear to be the case. 
 
 Importance of the Bark in Pharmacognosy. — Viewed from the stand- 
 point of pharmacognosy, the bark, especially when detached from the 
 remainder of the root or stem, is one of the most important portions 
 of the plant. As has been seen, it is not a simple structure, but develops 
 in part from the plerom, as well as from the periblem, and bears fre- 
 quently, although this is not true of any detached medicinal bark, the 
 epidermis as well. 
 
 Layers of the Bark. — In practice, the bark is commonly differentiated 
 into three layers — the Endophloeum, that portion resulting from the 
 plerom; the Mesophloeum, which is either the primary cortex, or the 
 products of a phellogen developing external to the endophloeum, or 
 both when they exist together; and the Exophloeum, consisting of a 
 primary periderm. If, as is not the case in any medicinal bark, the 
 epidermis persist, it will form the exophloeum. It has already been 
 made clear that a bark can come to want successively its exophloeum, 
 mesophloeum, and even the outer part of its endophloeum, as is seen in 
 some Cinchona bark, from old trees. 
 
 The study of barks includes a close examination of the cellular 
 elements, as a preparation for which histological work is absolutely 
 necessary. Examination of its gross characters involves, as the more 
 important features, its extreme and average thickness, its manifest 
 layers, as seen with a lens on transverse or radial section, their relative 
 thickness, color, markings, consistency as shown by fracture, their 
 
THE BARK 
 
 151 
 
 separability from one another, that is, into 
 laminae, together with the snrfac-e char- 
 acters of the latter, the external color and 
 level markin<;s, the jiresence and natnre of 
 parasites, and the color and inequalities of 
 the iinicr surface. 
 
 The Laminae- The laminae do not 
 dcixMid entirely upon diifcrent tissue com- 
 position. The same tissue, produced at 
 diiVcrent times, may ])resent differences 
 sufficient to result in different degrees of 
 cohesion, as well as markedly different 
 color, at different depths, so that separation 
 may readily occur, or they may readily l)e 
 distinguished in sections. 
 
 Section-markings. — Groups or radial or 
 tangential rows of tissue-elements, differing 
 from those adjoining, frequently produce 
 gross markings on the section-surface. 
 
 Fracture. — The fracture of barks or of 
 their individual layers is denominated in 
 general as being brittle or tough, ^'ari()us 
 modifications are soft, earthy, granular, 
 horny, waxy, fibrous, splintery, or flexible. 
 A bark may be flexible hi one direction and 
 not in another. 
 
 The Outer Surface. — The outer surface is 
 described in general as being harsh, rough, 
 downy, smooth or shiny, and its luster may 
 be waxv, ^•itrcons, and so on. Some of the 
 
 Fig. 425. Section of young Calisaya bark, showing wrinkling 
 in drying. 42G. Section of old Succirubra bark, showing 
 ridging. 
 
 Fig. 127. (^lili of mature Cali- 
 saya bark, sliowing transverse and 
 longitudinal fissures. 
 
152 GENERAL STRUCTURE OF ROOT AND STEM 
 
 elements causing roii^-hiiess may require mieros('()])ical examination 
 for their demonstration, while others are otherwise manifest. 
 
 Ridges and Furrows. — Care must be taken to distinguish between 
 ridging and furrowing of different kinds. One kind is caused by a 
 longitudinal wrinkling in drying, as in young Calisoya (Fig. 425). 
 Another is owing to transverse (as in old Calisaya) or longitudinal (in 
 the same) fissuring (Fig. 427). Another is caused by the elevation of 
 corky ridges, or rows of corky warts, which may or may not become 
 confluent in variable degree (as in Succiruhra, Fig. 426). Fissures may 
 characteristically open in the crest of a ridge or in the otherwise un- 
 changed siu-face. 
 
 Color-markings. — Most color-variegations are due to lichens or 
 other parasites, and those due to lenticels are also very common. A 
 single color or shade of color of the inner surface is rarely characteristic, 
 as it changes very greatly with age in keeping; but a carefully arranged 
 series of them may be made diagnostic in many cases. 
 
 The Inner Surface. — The important characteristics of the inner 
 surface depend upon the projecting bast-bundles caused by contracting 
 medullary rays. Very rarely, indeed, is the surface so free from these 
 inequalities that it can be properly described as smooth. The slightest 
 manifestation of the bundles gives the Striate condition. The striae 
 must be examined as to length, straightness, direction as contrasted 
 with the axis of the bark, apparent interconnection at the end, width, 
 elevation, and sharpness, with the complementary characters of the 
 intervening furrows or pits. Some barks show a tendency to separate 
 into laminae which run obliquely out upon the inner face, appearing 
 there as partially separated tongue-shaped splinters. 
 
 No attempt has ever yet been made to classify the markings of the 
 inner surfaces of dried barks, and to provide a terminology for them. 
 In the absence of this important treatment, it is difficult to teach the 
 details of the subject, except by the use of the actual objects. 
 
(' II A PTK K X 1 \' 
 
 VERTICAL AND LATERAL EXTENSIONS AND APPENDAGES 
 OF THE STEM 
 
 Origin of Branches and Leaves. — Examining a radial section of the 
 tip of the stem (Fig. 4) we find, in addition to the structures already 
 considered as helonging ])rimarily to itself, protuberances, consisting 
 of masses of meristem tissue belonging to the periblem and the derma- 
 togen. Shortly, each of these tissue-masses assumes, in a general way, 
 the condition of the primary growing point of the main stem. Some 
 of them will develop into leaves, the structure of which will be con- 
 sidered farther on, others into branches, which latter j)r()cess is a mere 
 repetition of that already considered in relation to the })rimary stem. 
 In either case, the vascular bundles exhibit a connection, variable in its 
 details, with those of the stem from which it develops. 
 
 Arrangement of the Leaves and Branches. — The normal method is for 
 a l)ranch and leaf to develop together, the former in the axil of the 
 latter, as already recorded. If two or more leaves, with their branches, 
 develop at the same node, it results in the opposite or verticillate 
 arrangement. If but one, then, of those developing at different levels, 
 each is successi\ely separated from the former by a uniform portion of 
 the stem circumference, so that a spiral arrangement results. This 
 s])iral will be considered when we come to the study of the leaf. 
 
 Growth of the Internodes. The ])oiiit at which one or more leaves 
 de\elop has alread\' been defined as the node, and the poi'tion of stem 
 intervening between two nodes as the internode. At first tlu- internodes 
 are so short as to be scarcely perceptible, but they continue to grow 
 in all j)arts until a length more or less definite for the sjiecies is attained, 
 so that leaves and branches become separated by imiform vertical as 
 well as circumferential spaces. This brings us to another great distinc- 
 tion between tli(> stem and the root, in which latter we lia\-e found a 
 contiiuions and uniform longitudinal de\elopnient. 
 
 Axils in which Buds do not Develop. The rule that a branch de\eloi)s 
 in each leaf-axil is habitually (lc|)arted from in the leaf-representatives 
 constituting the flower, and accidentally in sonic other cases. Its 
 failure to devel()|) may be tem]jorary, although oftiMi \-cr\ long con- 
 tinued, or it may be permanent. 
 
154 EXTENSIONS AND APPENDAGES OF THE STEM 
 
 Occasional Failure of the Leaf to Develop. — U])()n the other hand, the 
 subtending leaf may fail, accidentally, or in a few cases habitually, to 
 develop, so that the branch does not show its axillary nature. 
 
 Abnormal Position of Branches. — Finally, we note that a branch may 
 accidentally, or in some cases habitually, develop from some other 
 point than the leaf-axil, or two or more may develop, at least partially, 
 from one axil, either side by side or in a vertical row. 
 
 Not only may a lateral branch thus fail to develop, but the apical 
 extension of the growing point may fail, accidentally or habitually, 
 the growth being continued by means of one or more branches only. 
 
 Sympodial and Monopodial Stems. — When this method of growth is 
 characteristic, the new branch taking the place of the suppressed stem 
 which produced it, at each successive node, so that the stem becomes 
 composed of a succession of one-jointed branches, the stem is called 
 Sympodial, as contrasted with the term Monopodial, for the ordinary 
 form, in which the apical growth, as well as that of the branches, is 
 continued from joint to joint. 
 
 The natural result of such a series of branchings would be to produce 
 an angular divergence of the axis at each joint, as the branch projects 
 more or less laterally from its support. This, however, is usually not 
 the case. In many plants the new branch takes the erect position of 
 that which it has replaced, preserving the rectitude of the axis, and so 
 tending to obscure the sympodial nature of its growth. In such cases, 
 we must search for other indications of its nature. This subject will be 
 understood upon reference to the accompanying diagrams (Figs. 428 
 to 430), in which a in each case represents the apical extension, b the 
 leaf, c the axillary branch. It is seen that the positions of the three, 
 with relation to each other, are the same in every case, the axillary 
 branch being between the other two, no matter what changes in their 
 directions may occur. In Fig. 429 the apical phytomer has been 
 forced a little to one side, while in Fig. 430 it has become perfectly 
 horizontal, the branch substituting it in the erect position. It is clear 
 that in the last case, c might easily be mistaken for the main stem, 
 a for a branch. If this view is taken, however, we are at once met by 
 the difficulty that the supposed branch has no leaf at its base, that is, 
 it is not axillary, while the leaf, b, has no branch in its axil. Both these 
 difficulties entirely disappear when we regard the body between the 
 other two as the branch. 
 
 A mistake becomes even more easy when one of the structures 
 becomes modified into some unusual form. Thus, in Fig. 431, the 
 
SYMPODIAL AND MONOPODIAL STE.\fS 
 
 155 
 
 terminal pliytonicr has become converted into a tendril (a). This 
 tendril must be a modified main stem, a modified l)ranch, or a modified 
 leaf, and the decision is perfectly easy when we intjuire as to its relation 
 to tlie axil. In Fig. 432, where the apical j)ortion has become converted 
 into an inflorescence, followed by a cluster of grapes, the determination 
 is the same. 
 
 In all these ilhistrations but one phytonier witli its ])r()(hicts is 
 displayed. By viewing a series of them, we are a})le to determine a 
 number of distinct forms of the sympodial stem, depending upon the 
 order of its branching. In Fig. 433 the branches are borne alternately 
 upon the two sides, and directed alternately to right and left, giving 
 
 fffl*.1 
 
 Figures illustrating sympodial growth: Fig. 428. a, superposed phytonier; I, leaf; c, axillary 
 phytomer or branch. 429. o, turned aside; b, assuming its place. 430. The change complete, the 
 superposed phytomer become lateral, standing opposite the leaf. 431. (The grape) same positions as 
 in 430: a, metamorphosed into a tendril. 432. a, converted into an inflorescence. 433. Alternating 
 sympodial growth. 434. Unilateral sympodial growth. 435. Bifurcating sympodial growth. 
 
 a flexuous appearance to the sympodium; but it must not be forgotten 
 that they may grow quite erect, the leaves alternating regularly upon 
 the two sides and the stem appearing monopodial. No axillary branches 
 will, however, be found. In Fig. 434 the branches develop successively 
 upon the same side. In this case, also, the fully developed portion of 
 the stem is straight and api)ears monopodial, exce])t that the leaves 
 are all upon one side (secmul), but the ])eculiar direction taken by the 
 undeveloped portion toward the tip indicates its true nature, as well 
 as the absence of axillary branches. Fig. 435 represents a sympodial 
 stem on which the branches are borne in ])airs, the obvious result being 
 a double symmetry, each branch successively ending in a pair of 
 
156 
 
 EXTENSIONS AND APPENDAGES OF THE STEM 
 
 branches. This gives us the forked or Bifurcating form of sym])0(linm, 
 often called (Hchotomous, though this term refers strictly to one in 
 which forking is caused by the vertical division of a terminal cell. 
 
 Superficial Appendages to Stems. — Besides modified or unmodified 
 leaves or branches, stems may develop various other ai)i)endages. 
 When these are merely superficial, they are called Trichomes. The 
 characters of trichomes upon stems or leaves, particularly the latter, 
 are of the utmost importance in diagnosis. Their study, however, 
 save as to the surface characters which they collectively produce, 
 pertains to histology. The gross surface character so produced will 
 be taken up in connection with the leaf. 
 
 Fig. 430. Aculeate stem of Chadaea. a, hooked prickles. 
 
 Emergences or Outgrowths. — When ai)pendages are of deeper origin 
 they are called Outgrowths or Emergences. These may contain vascular 
 tissue, connected with that of the stem. Outgrowths are, for the most 
 l)art, in the form of spines, hooks (Fig. 436, a), warts, suckers (Ing. 459, 
 a, in this illustration a modified stem), or grasping organs. Usually 
 organs of this kind are the results of modifications of other organs, 
 rather than outgrowths. Both trichomes and outgrowths may be 
 regularly or irregularly disposed. 
 
DUDS 157 
 
 Roots from Stems. — Roots may develop from branches which are 
 subterranean or which rest upon the surface of the ground or are high 
 above it. Tlie hitter may descend and enter the ground, fix themselves 
 to a neighboring body for sustenance or support, or both, or extend 
 into the atmosphere. 'V\\v\ may c\cn turn and cntci- a (lisca>c(l (ir 
 decaying ])()rti()n of their own ])lant. They normally (h'xcloi) from the 
 nodet)nly, but may dcxclo]) from any other ])art or ('\('n fi-om h'a\es. 
 
 Buds. — An undeveloi)e(l stem or branch, or the i)artially developed 
 summit of one, is a Bud or Gemma. The bud may be in a process of 
 continuous development of its lower elements into mature phytoraers, 
 with the continuous ])roduction of a new growing point, or it may 
 pass into a resting state between successive seasons of growth. In 
 the latter case it undergoes special modifications (6 in Figs. 447, 448, 
 and 450). Its outer leaves become developed previous to the resting 
 stage, but not as foliage leaves. They become modified instead in 
 various directions as to form, proportions, relative position, apjjend- 
 ages, and exudations, to fulfil tlie office of protection as scales, 
 and they subsequently fall away, ne\cr devel()i)ing into foliage leaves. 
 When no such provision is made, the bud is commonly destroyed, with 
 more or less of the young stem tip near it, during the resting period. 
 Occasionally the bud is protected for a time by a special covering, formed 
 by the petiole of the subtending leaf. It is then called a Subpetiolar 
 Bud. 
 
CHAPTER XV 
 
 CLASSIFICATION OF ROOTS AND STEMS 
 CLASSIFICATION OF ROOTS 
 
 Roots may be classified as to their duration, their order in time of 
 development, place or nature of origin, function, form, and consistency. 
 
 Duration of Roots. — As to duration, we have roots divided into two 
 great classes, although the terms designating them are in general applied 
 to the plant as a whole rather than to the root. Monocarpous plants 
 are those which die after producing one crop of fruit; Polycarpous, 
 those which produce successive crops. The former are Annual when 
 they live but a single season — as the rag- weed and the sunflower; 
 Biennial, when they devote the first season to the storing up in some 
 receptacle, such as a fleshy root or bud, a supply of nutriment, and 
 fruit and die in the second season. The term winter-annuals has been 
 applied to those which begin their life during the latter part of the first 
 season, fruiting early the next season, so that their combined life during 
 the two seasons is less than twelve months, as in the case of wheat and 
 rye. Such may, by being planted early in the season, finish their 
 existence during one season, as in the case of spring wheat. Those 
 monocarpous roots which devote a number of years to the preparation 
 for fruiting, as in case of the century plant, belong to the Perennials. • 
 All Polycarpous roots belong, of course, to the perennials. 
 
 Order of Development. — Primary and Secondary Roots. — As to their 
 order in time of development, the first root developing from the radical 
 is the primary. All subsequently developed, whether from root or 
 stem, are secondary, although those developing from secondary roots 
 are sometimes designated Tertiary and so on. 
 
 The Tap Root. — If the primary root continue its development so as 
 to constitute a branch-bearing axis, it is called a Main-root or Tap-root 
 (F'ig. 439). The ultimate behavior of the tap-root, when not of the 
 fleshy- thickened storage class, depends upon the development of the 
 leafy crown of the stem. The extent of root-growth and its development 
 will agree with that of the stem-crown. Two forms of stem-crown are 
 
ORDER OF DEVELOPMENT 
 
 159 
 
 rcc'()f];nized, the one liaviiiji; its l)raiiclie.s and leaves so disposed as to 
 coiidiict the rain whieh falls upon them in toward and down the stem, 
 the other condnctinjj; it outward, so as to fall from the perijjhery. An 
 examination of the former elass of plants may be expeeted to diselose 
 a ta])-r()()t which maintains a \ertical downward direction, its branching 
 not hein^' wide. TJiose of the second class will generally he found to 
 ha\c their tajj-roots (piickly dividing u]) into innncrous horizontal 
 branches which bear the greater part of their small absorbing rootlets 
 around the perii)hery, just where they will catch the droppings from the 
 peri])hery of the leafy crown. 
 
 Fig. 437. Tubercles of Jalap. 438. Death of first portion of stem, it.s subsequent growth maintained 
 by cluster of secondary roots. 439. Tap-root, with branches, of .4 TO6ro.sia, 440. Underground portion 
 of potato plant: a, tubers; h, rhizomes, the roots seen intermingled. 441. A napiform fleshy root. 
 442. Fusiform. 443. Conical. 
 
 The "Multiple Primary Root.'' — If the primary root of a very young 
 plant divide at once into a number of approximately equal branches, 
 it constitutes the so-called ]\Iultiple Primary Hoot. This term has, 
 however, been applied to a number of root-dusters of similar appear- 
 ance, but of very dissimilar origin. In some cases the primary root 
 continues its vertical growth but does not increase in thickness to any 
 a])preciable extent. A number of similar roots then develoj) near its 
 l)oiiit of origin, so that a fascicle of similar I'oots at length results, as in 
 the onion. In other eases a prostrate stem takes root from one of its 
 nodes, the j)()rtion below this point (Fig. 438, a), with the original roots. 
 
160 CLASSIFICATION OF ROOTS AND STEMS 
 
 perishing. To the ckister of roots thus resulting, although they are 
 really secondary, the term "multiple primary" has also been applied. 
 A true multiple primary root is of rare occurrence and does not exist 
 among drugs. 
 
 Adventitious Roots.— AW roots which are not primary, or branches 
 thereof, and all branches of roots which are not de\'eloped in regular 
 order of succession, are called Adventitious. 
 
 Place and Nature of Origin. — Subterranean and Aerial Roots. — As to 
 their place and nature of origin, roots are Subterranean when they 
 originate from points underground, whether from root or stem, and 
 Aerial when they originate from points above the surface, whether from 
 root or stem. A root may originate from an aerial point and afterward 
 fix itself in the earth, as the Brace-roots of maize. 
 
 Fascicled Roots. — A number of approximately equal and similar 
 roots occurring in a cluster, especially if they be fleshy-thickened, are 
 denominated Fascicled. 
 
 Fibrous Roots. — Roots existing in the form of a mass of thin, fiber- 
 like, approximately equal and similar elements are called Fibrous 
 (Fig. 446). 
 
 Functions of Roots. — As to their functions, roots are known as Absorb- 
 ing, Fixing, and Storage roots. A root of one kind may give origin to a 
 branch of a different kind. 
 
 Haustoria. — Absorbing roots of parasitical plants are frequently 
 greatly modified in structure to form Haustoria. 
 
 Rhizoids. — Fixing roots are usually designated as Rhizoids. 
 
 Storage Roots are usually much enlarged and possess a fleshy con- 
 sistency and characteristic forms (Figs. 441 to 443). 
 
 Tubercles. — When only a limited portion of a root is fleshy-thickened, 
 so as superficially to resemble a tuber, it is called a Tubercle, as the 
 Jalap (Fig. 437). Care should be taken not to confuse this technical 
 meaning of the term with its common use as designating a small tuber. 
 
 Forms of Roots. — As to their form, roots are simple, when they do not 
 branch, or Branched, Cylindrical, Terete (which includes the cylindrical 
 and that form which differs only in that it tapers), Xapiform, when 
 taking the form of a short, broad turnip (Fig. 441), Fusiform when 
 spindle-shaped, as some radishes (Fig. 442), Conical or Cone-shaped 
 (Fig. 443), Capillary when very thin, long and 'hair-like. 
 
 Consistency of Roots. — Woody and Fleshy Roots. — As to consistency, 
 they are denominated as Woody and Fleshy. By "fleshy" or "non- 
 woody" we do not mean that wood tissue is entirely lacking, but rather 
 
nruMios 101 
 
 tliat the })r()i)()rti{)ii of the (rllulnr, paroiidiymatic, or fiesliy elements 
 is so mueh <]jreater than that of the woody that a woody eharaeter is not 
 apparent. In practical pharmacognosy, where dried roots are mostly 
 observed, a number of other terms for consistency, as in the case of the 
 hark, come into use. 
 
 CLASSIFICATION OF STEMS 
 
 Stems may he chissified as to duration, order of d('\ cloiJinciit in time, 
 position, and nature of origin, mode of extension, direction of ii;rowth 
 and nature of sup])ort, modification of form or function, and consistence. 
 
 Duration. — As to duration, they are, like roots, Annual, Biemiial, and 
 Perennial. 
 
 Ilrrhs. — Annual stems are those which die at the close of the season. 
 They may or may not i)ertain to annual roots. Plants possessing them 
 are called Herbs. Herbs are therefore either Annual, Biennial, or Per- 
 ennial, in accordance with the character of the root, but their stems 
 are always annual. The definition of an herb is a plant, the aerial 
 portion of which dies at the season's close. The stem of an herb is 
 denominated Herbaceous. 
 
 Biemiial Stems. — Biennial stems are those which are jjroduced, 
 usually underground like that of the potato (Fig. 440, b), during one 
 season, and perish after the production of their branches in the following 
 season. Occasionali\", howexcr, like the cabbage, a biemiial stem is 
 aerial. 
 
 Tubcn'. — Fleshy-thickened and biennial portions of niidcrgronnd 
 stems, such as the ])()t;ito, ai'c denominated Tubers (Fig. 410, (i). l''ig. 
 444 represents tiic undei-ground poi-tion of the ('iirciniKi, and well 
 displays the dill'erence between tubers and tubercles. 
 
 Bulbs. — Basal biennial portions of stems which are invested by more 
 or less fleshy-thickened storage-leaves are called Bulbs. J5ulbs will be 
 classified under the subject of buds. 
 
 Perennial Stems. — Perennial stems are those which Wvv and extend 
 their growth from year to year. They are Determinate when their 
 growth of the season is self-limited and closes with the production of a 
 sj)ecially i)repared Winter-bud, which protects the growing point for 
 continued growth tlie next season; Indeterminate, when no such bud 
 is formed, growth contimiing until the aj)ical portion is destroyed by 
 an incl(Mnent season. In the latter class we have the anomaly of a 
 ])ereiiiiial stem with an annual ti[). 
 11 
 
162 
 
 CLASSIFICATION OF ROOTS AND STEMS 
 
 Order of Development. — Primary and Secondary Stems. — As to their 
 order of fle\elopment in time, stems are Primary, Secondary, and so 
 on, terms which are self-explanatory. 
 
 Place and Nature of Origin, — Aerial and Subterranean Stems. — As to 
 their j)()sition and nature. of origin, stems are Aerial or Subterranean, 
 which terms are also self-explanatory. A secondary stem assuming an 
 erect position from the base of the primary, like those of the Indian 
 corn, is a Sucker. Such an one arising from a rhizome at a considerable 
 distance from the original erect stem, as in the blackberry, is called a 
 Stolon. A short secondary stem developing from the base of the primary 
 is called an Offset. An elongated, slender one, lying prostrate and 
 rooting at some of its joints, is called a Runner (Fig. 445). 
 
 Fig. 444. Tubers of Curcuma. 
 
 44S. 
 
 445. Runner of strawberry plant, 
 scaly rhizome of Gesneria. 
 
 446. Fibrous roots attached to 
 
 The Rhizome. — An underground stem, fleshy-thickened at least during 
 the first year, so as to serve as a storage receptacle, and giving origin 
 to an aerial summit or branch, is a Rhizome (Figs. 447 to 452). 
 
 Distinctions betiveen the Rhizome and the Root. — A rhizome is very 
 frequently mistaken for a root, but the differences, both internal and 
 external, are well-marked. The internodes of the rhizome are com- 
 monly quite as uniform in length as those of the aerial stem. The nodes 
 are usually conspicuous. Leaves exist upon them, commonly in the 
 form of scales. Occasionally these scales are numerous and well formed 
 (Fig. 446), but usually they are rather obscure, as in the potato, where 
 they are mere semicircular or crescent-shaped ridges about the eyes. 
 In the axils of the scales, buds are usually to be distinguished. These are 
 the so-called "eyes" of the potato, and their develoi)ment into branches 
 is a familiar phenomenon. Internally, the structure of the rhizome is 
 in general that of the stem, though fleshy tissue predominates. 
 
 The growth and duration of a rhizome may be indefinite, like those of 
 stems, as in the case of the rhizome of Podophyllum (Fig. 449), or they 
 may be restricted to one or to a definite number of }ears, after which the 
 
PLACE AND NATURE OF nUKlIN 
 
 163 
 
 oldest existing; ])liyt()nu'r ])erislios each year as a suceessi^■e a])ical one 
 is formed (Fij;. 450, h). 
 
 Forms of Rhizomes. — Rhizomes are so inimeroiis and important in 
 pharmacy that their characters call for special attention. They are 
 classed as short or elongated, the former term referring to those 
 
 4S2. 
 
 Forms of rhizomes: Fig. 447. Convallariti, with :iiiiiular roots: «, terminal l)ii<l. 448. Cimicifiii/n, 
 its cup-shaped stcni-scars much elevated. 449. Podophyllum, its intcrnodes elongated. 450. Poly- 
 poria/UOT, its cup-shaped scars depressed. 451. /n's, its roots aggregated at one end. 452. Acorus, with 
 V-shaped leaf-soars. 
 
 the extreme length or shortness of which fall within certain fairly 
 defined and restricted limits; the latter, those which cither j^ossess an 
 indefinite extension, or the definite length of which is a great many 
 times their thickness. Terms indicati\e of their form and consistency 
 do not differ materially from those a])i)lied to other stems and to roots. 
 They are almost always sympodial. They are very subject to flatten- 
 
164 CLASSIFICATION OF ROOTS AND STEMS 
 
 ing, the flattened surfaces usually looking upward and downward. The 
 presence or absence of branches is always characteristic. The manner 
 in which the roots take their origin is c(|ually so. These may form a 
 circle (Fig. 447) or be restricted to the under surface (Fig. 449). The 
 number of roots developing from a node is usually fairly characteristic. 
 So is the persistency or brittleness of these, and the characters of the 
 stumps or scars which they leave, as well as their form, which is very 
 often triangular or quadrangular in section. Their structure, as observed 
 either with the lens or with the microscope, is characteristic and of 
 diagnostic value. Sometimes the roots are not only restricted to a 
 certain portion of the node, but in the case of short rhizomes are re- 
 stricted to a definite portion of the latter (Fig. 451). The relative length 
 of the internodes of a rhizome, as compared with its diameter or thick- 
 ness, calls for close attention, and so does the absolute or measured 
 length. The relations of the erect portions to the horizontal, and the 
 stumps or scars left by the former upon their death or separation, con- 
 stitute one of their most important diagnostic characteristics. Com- 
 monly, disarticulation occurs, with the production of a cup-shaped scar. 
 This scar will be characteristic as to whether it form a depression in the 
 general surface (Fig. 450) or be elevated upon a base (Fig. 448), as will 
 the length of the latter, the form and depth of the scar, and the char- 
 acter of its edge. The size of the scar, that is, its lateral breadth as 
 compared with the thickness of the internode, is also noteworthy. 
 Leaf scars, or leaf remains, upon rhizomes call for the same examination 
 as do the stem scars. They may surround the entire rhizome, in which 
 case they are designated Annular, or they may be confined to the upper 
 surface. If the latter, the scar may be of characteristic form, as linear, 
 elliptical, circular, cordate, crescent-shaped, or ^"-shaped (Fig. 452, a). 
 Finally, we note that annular or longitudinal folds, thickenings, wrinkles, 
 or constrictions are characteristic of certain rhizomes as well as of roots, 
 particularly in the dried state. 
 
 Mode of Extension. — Simple and Branched Stems. — As to their mode of 
 extension, stems may be Simple or Branched. A stem denominated as 
 simple is not necessarily entirely destitute of branches, as floral branches 
 or small branches near the summit are permitted. It has already 
 been shown that stems may develop monopodially or sympodially. 
 The stem of a tree which continues, except in case of accident, to develop 
 monopodially, as the Fir, is called Excurrent. One which after a time 
 loses its main stem in a number of branches, as for instance the elm, is 
 Deliquescent. 
 
MODIFICATION OF FORM OR FUNCTION 1G5 
 
 Acauh'scent Plants. — The term Acaiileseent, wliile strictly meaning 
 stemless, can, of course have no such ai^phcation, as all fiowering plants 
 possess a stem, even before germination occurs. The term is applied 
 to those plants whose stems arc so short as not to become con- 
 si)icu()us. 
 
 The Crou'ii. — The stem of sudi a plant is called a ("rowii. The term 
 crown is also appUeil to the branching or leafy portion of any stem. 
 
 Trees, Shrubs, and Vudcrshruhs. — A plant possessing a woody and 
 erect stem rising singly to the height of fifteen (according to some 
 authorities, twelve) feet or more is denominated a Tree, or Arborescent 
 plant, although the precise application of such a term is impossible. 
 A perennial woody stem which has not these characters is called a 
 Shrub or a Fruticose stem. Very small shrubs appearing on causal 
 insi)cction as herbs are called Undershrubs or Suffruticose plants. 
 
 Direction of Growth and Nature of Support. — As to the direction of their 
 growth and the nature of their supjjort, stems may be Erect, in which 
 case they are erect through their entire length; Ascending, in which case 
 the base for a greater or less distance rests upon the ground, the terminal 
 portion becoming erect; Horizontal, in which case they are considered 
 as having no other support than the parent stem, from which they 
 extend at a right angle; Drooping, in which case they are first hori- 
 zontal, the outer portion becoming pendant; Pendant, or "Weeping," 
 when they are pendulous from their point of origin or almost therefrom; 
 Decumbent, when at first erect or supported by the i)arent, the outer 
 l)()rtion dechned so far as to rest upon the ground; Reclining, when 
 resting ui)on some means of sui)i)ort elevated above the earth, as over 
 the t()i)s or branches of other i)lants; ProcnmlxMit, when resting at full 
 length upon the ground witlioiit rooting at the joints; Repent, or 
 "Creeping," when ])rostr;itf and rooting at the joints (Fig. 445); 
 Twining, when sup])orting themselves by the twining of the stem itself 
 around a support; Climbing, when elevating and sui)porting them- 
 selves by other methods than a twining habit, the principal forms being 
 the Cirrhiferous, when climbing by tendrils (Fig. 4;-51), and Aculeate, 
 when cliinbiiig i)y hooks (Fig. 4;]()). 
 
 Modification of Form or Function. — Mixli/ird Sfews. — As to modifi- 
 cation of form or function, stems arc snbj(>ct to a somewhat elaborate 
 classification. 
 
 They may be modified for the ])uri)osc of defence, that is into thorns 
 or spines (Fig. l.").'i), altliongli not all thorns or spines arc transformed 
 branches. Some branches of this foi'ni remain so permani-ntly, while 
 
IGG 
 
 CLASSIFICATION OF ROOTS AND STEMS 
 
 others become foliaceous later and de\'elop into branches of the ordinary 
 form (Fig. 454). 
 
 For the purpose of cHmbing, they may become cirrhose, that is, 
 converted into Tendrils. The tendril may consist of the apex of the 
 
 ^6. 
 
 Illustrating modified stems: Fig. 453. Branch converted into thorn. 4.54. The same becoming leafy. 
 455. Branch of Strychnos, becoming a tendril. 456. Stem of Lemma, modified like a leaf. 457. 
 Branches of a species of Asparagus, modified as leaves. 458. Condensed stems of Opuntia. 459. 
 Branches of Ampelopsis metamorphosed into disks. 460. Branches of Phyllanthus, modified like 
 leaves, but flower-bearing. 
 
 primary stem (Fig. 431), or one of the branches may become the tendril, 
 as in Strychnos (Fig. 455). In the latter case the tendril will stand in 
 the axil between leaf and stem; in the former it will stand upon the 
 opposite side of the stem from the leaf, for reasons already explained. 
 A stem may instead become converted into a sucking disk, as in the 
 
MODIFICATION OF FORM OR FVSCTION 167 
 
 case of Ami)eloi>sis (Fig. 459, a). In this case the tip of tlie branch or 
 stem becomes flattened and attaches itself very tightly to the supporting 
 surface; so tightly, in fact, that a portion of stone or a splinter of wood 
 may be torn from its support before the disk can be made to separate 
 from it. Plants which grow in the water or in places subject to inunda- 
 tion may have portions of their stems inflated into bladdery forms to 
 insure a floating condition. Such structures are, however, more com- 
 monly of a leafy nature. 
 
 Cladoidia or Cladophylla.- — Stems may become modified for the j^er- 
 formance of the office of leaves. Such a stem is called a Cladoidium or 
 Cladophyllum (Figs. 457 and 400). For this purpose the whole stem 
 may become modified into a single leaf-like organ, as in the case of 
 certain aquatics, in which case it is known as a Frondose Stem (Fig. 
 456). Upon the other hand, separate portions of the stem or separate 
 branches thereof may become thus modified, as in the case of the so- 
 called "leaves" of the species of Asparagus cultivated as a decorative 
 plant under the name of Smilax (Fig. 457: a, leaf; 6, branch). Some- 
 times a stem or a joint of one, at the same time that it becomes modified 
 to perform the office of a leaf, performs the ordinary offices of a stem, 
 or important storage functions as well, as in the case of the Opnntia 
 (Fig. 458), and the Phyllanthus (Fig. 400). Such stems are called 
 Consolidated. Branches like those in Fig. 400, modified to perform 
 the leaf-function, are called PhyUocIadia. 
 
 ]\Iany trees have been encountered by the author in troj)ical America, 
 the stems and branches of which are hollow (denominated fistulous), 
 afl'ording permanent homes to myriads of ants, which, deriving their 
 sui)port from the tree, are supposed to confer some compensatory 
 benefit upon it. They at least protect the tree against animal attacks, 
 being in all cases extremely savage and venomous. 
 
 Besides such specially modified forms, a number of ordinary forms 
 are characterized by the adjectives Terete, Cylindrical, Compressed, 
 Triangular, Quadrangular, Alate or Winged, Costate or Ribbed, Chan- 
 nelled, Striate, and so on. In this connection the terms a])plicable to 
 the superficial characters of barks already described, and those con- 
 nected with leaf-attachment, to be described farther on, should be 
 studied. In addition to the above-mentioned stem-forms, which admit 
 of ready classification, we have a large number of modifications to efi'ect 
 special purposes, which must be considered individually. As these 
 ])ossess but a slight interest in relation to pharmacognosy, we refer the 
 interested student to more general works on botany. 
 
168 
 
 CLASSIFICATION OF ROOTS AND STEMS 
 
 Storage Stems. — An important office of the stem is the storage of 
 nutriment. All stems perform this office to a greater or less extent, 
 but some are especially modified in form for the purpose. Of these, we 
 have already specially referred to rhizomes and tubers. 
 
 The Bulb. — It remains, then, only to consider the various forms of 
 the bud, including in this term all forms of the bulb. A bulb which, 
 like the onion (Fig. 462), has its fleshy-thickened leaves in the form 
 of broad sheathing organs, seen upon transverse section in the form 
 of concentric rings, is called Tunicated or Coated. Those like the lily 
 (Fig. 461), in which these leaves appear in the form of narrower pro- 
 jecting scales, are called Scaly. When in the axils of the scales we find 
 
 Fig. 461. Scaly bulb of Lilium. -iC^. Tunicated bulb of onion. 463. Corm of Gladiolus. 464. 
 Axillary bud-bulb of tiger lily. 465. Terminal head of bulbs of onion. 
 
 smaller or secondary bulbs or buds, as in the garlic, it is a Compound 
 bulb. When the texture of a bulb is so dense that its leaf-elements are 
 not conspicuous, it is designated as a Solid bulb. When it is still more 
 dense, as in the case of the Gladiolus (Fig. 463), so that the leaves are 
 not to be distinguished by ordinary methods, it is a Corm. In some 
 plants, the axillary bulbs, instead of occurring in the axils of the bulb- 
 leaves, occur higher up in the axils of the ordinary foliage-leaves, as in 
 the case of the tiger lily (Fig. 464). Their true nature as buds is in 
 this case conspicuously shown, and they are sometimes spoken of as 
 Bud-bulbs. In other related plants, similar bulbs are densely aggre- 
 gated in a terminal umbel looking like an inflorescence, as in some 
 species of onion (Fig. 465). 
 
CLASSES OF BUDS 109 
 
 CLASSIFICATION OF BUDS 
 
 Buds ])ro])er admit of an elaborate elassifieation, whieh, although not 
 of such interest in pharmacognosy as to warrant its study here, is of 
 fundamental im})()rtance in systematic botany, and furnishes a key to 
 many ])roblems which are otherwise abstruse. 
 
 Vernation and Praefoliation. — The study of buds is called A'ernation, 
 and that of the arrangement of the leaves composing them Praefoliation. 
 In general, the arrangement of leaves in the bud admits of the use of 
 terms similar to those ai)plied to the parts of the perigone in a similar 
 state. 
 
 Classes of Buds. — Buds may be classified as to their structural form, 
 their position, and parts. A winter bud which protects itself by specially 
 developed scales is known as a Scaly bud; one which does not, a Naked 
 bud. A bud consisting only of leaves is a Leaf bud ; one only of a flower, 
 a Flower bud; one consisting of both, a INIixed bud. Solitary l)uds 
 occurring in the axil of the leaf and developing at the regular time are 
 called Normal buds. Any buds in addition to the normal bud, occurring 
 in the leaf axil, are called Supernumerary. They may be situated above 
 or at the side of the normal bud. The normal bud is sometimes situ- 
 ated a little above the actual axil, in which case it is called Supra-axillary. 
 All the buds here noted are denominated Lateral, in contradistinction 
 to the single terminal bud, but it is to be noted particularly that buds 
 lateral as to their origin may become terminal through the effects of 
 sym))()dial growth. Buds which dcNelop at other points than the aj)ex 
 or axil- as, for instance, fi'oin an internode, a leaf, or, rarely, even from 
 a root, as well as those of axillary origin, but developing out of their 
 regular order — are called Adventitious. The latter form of aihen- 
 titi(nis buds, when I'csulting from retarded dcNcloitnieiit, are know n as 
 Latent buds. 
 
CHAPTER XVI 
 
 THE LEAF 
 
 Importance of Leaf-study. — To the pharmacognosist a thorough 
 knowledge of the leaf is a necessity. Of its cellular structure, little can 
 be learned without the aid of the compound microscope. Its gross 
 parts were briefly referred to in our opening chapter, and these must 
 now be studied in detail. 
 
 Development of the Leaf. — The varied forms of structure which leaves 
 present can best be understood by considering them as modifications of 
 an original or primary leaf and noting the changes in the latter which 
 have occurred to produce them. It is apparent that such a primary 
 leaf was a mere scale of small size, as indicated in Fig. 466. It then 
 appears that any modern foliage leaf must have resulted either from 
 the uniform growth and development of all the parts of such a scale, or 
 from the greater relative growth of some one or more of its parts. The 
 result of its luiiform growth would be a leaf of the same form, but larger, 
 its base sheathing the stem, as represented in Fig. 467. But leaves of this 
 exact character are rare, from which it would appear that modern leaves 
 generally represent unequal degrees of development of the different 
 parts of the original leaf. Their attentive examination shows that the 
 following parts of such a primary leaf have in different cases undergone 
 independent enlargement and development. In Fig. 468, the portion a, 
 cut off by the dotted line at the top, may represent the Apical region; 
 that at h the Central-basal; the strip a-h the axial; and the remaining 
 portions upon either side (c and d) the lateral. Let us assume first that 
 the enlargement is confined chiefly to the central-basal portion. The 
 base will then become converted into the form represented in Fig. 469, 
 without the enlargement of the other parts there shown, this leaf being 
 a mere sheath around the stem, bearing the original scale at its tip. 
 Leaves of this form are rather common upon undeveloped or partly 
 developed stems. They are called Leaf-sheaths, or often, for emphasis, 
 Naked Sheaths. The edges of such a sheath may cohere after passing 
 around the stem, giving us the Closed Sheath, as in the sedges {a, in Fig. 
 465 B), or they may remain free, giving us the Open Sheath of the 
 
DEVELOPMENT OF THE LEAF 
 
 171 
 
 grasses {a, in Vv^. 4().5 A). Instead of passin^^ around the stem, tlie 
 edges may come together between the leaf and the stem, so as to produce 
 a hollow tube, as in the Sarracenia. Let it next be assumed that the 
 apical portion, as well as the central-basal, enlarges, with little enlarge- 
 ment of the axial or lateral portions. We shall then get a form in which 
 a Lamina, or Leaf-blade, is superposed directly upon a Leaf-sheath, 
 Such a leaf, expanded, would appear as in Fig. 470, if the blade were 
 
 46SA. 465 B. 4Y0. 47/ 
 
 4r2 
 
 Figures illustrating the origin and development of the parts of the leaf: Fig. 465 .-1. The grass-leaf: 
 a, the open sheath; h, the ligulc. 4()o B. Tlie sedge-leaf: a, the closed sheath. 466. The primordial 
 leaf, a mere scale. 467. The same, as equally developed in all parts. 4GS. The same, divided into its 
 different regions: o, the apical portion; b, basal portion; c and d, lateral portions with axial portion 
 between. 469. The same, undeveloped except the basal portion, which becomes a sheath to surround 
 the stem. 470. The same, with the apical portion also developed to form a blade, the lateral and 
 axial portions undeveloped. 471. The same, with the lateral portions developed into stipules. 472. 
 The stipules with their inner margins connate between the blade and stem, their outer connate around 
 the stem, forming an upper sheath or ochrea. In 40.5 .1 they are connate only by their inner margins, 
 between blade and stem, forming the ligule. (Ailaptid from work of A. A. Tyler.) 
 
 but little developed, or it inight be deNcloped e(nially in botli ]iarts. 
 Both of these forms are fre(piently encountered. If now the hiteral 
 portions shall enlarge, the axial jjortioii not imich elongating, a lateral 
 appendage must result at the base ui)on eitiier side, as in Fig. 471. 
 These are the Stipules. If the stipules, insteatl of existing separately 
 in this way, shall incline together between the stem and the leaf, and 
 their inner edges cohere, it is clear that they must form a small blade 
 
172 THE LEAF 
 
 standing out upon the face of the leaf at its base, as h in Fig. 465 A. 
 This is the Ligule. The free edges of the Hgule may now pass around the 
 stem, meeting and cohering upon the other side, thus forming a sheath 
 above the basal portion, or true sheath (Fig, 472). Such a sheath is 
 called an Ochrea. If, lastly, it be assumed that the axial portion a-h 
 (Fig. 468) undergo an elongation much greater in proportion than the 
 enlargement of the other parts, we shall ha\e developed a long narrow 
 division between the base and the lamina, as c in Fig. 3, which is the 
 Petiole. It is thus seen that the view here taken will account for the 
 origin of every part of the leaf. The few illustrations here shown refer 
 only to certain combinations in the development of the difi'erent parts. 
 As a matter of fact, such combinations found among existing leaves are 
 innumerable, and this variety is increased by the fact that the growth in 
 any one of these parts may be chiefly lateral or chiefly vertical, and 
 that it may be confined wholly or chiefly to some special portion of 
 the part. The student will, nevertheless, be able, by bearing in mind 
 the typical possibilities here considered, to determine the plan of struc- 
 ture of most leaves. This view will also make clear the statement in the 
 opening chapter in regard to the absence of the blade, petiole, or other 
 parts from certain leaves. 
 
 It is interesting to note here that there is ample evidence to prove 
 that the rudimentary or scale-like form of leaves existed upon the 
 earliest flowering plants, so it would appear that the parts of their 
 flowers were developed from such scale-leaves, rather than from the 
 highly developed leaves which we now know. Against this, we have 
 to consider that those floral parts were probably of correspondingly 
 simple development, and that, in the higher plants of today, they 
 have undergone a development which has kept i)ace with that of their 
 leaves. 
 
 As to what constitutes the tyjjical leaf, we are confronted by two 
 views. Structurally considered, it must be such a leaf as represented 
 by Fig. 467, but such leaves, as we now see them upon plants, do not 
 apparently so well perform all the functions of the leaf as those which, 
 like Fig. .'!, have developed the modern leaf-parts. 
 
 The Leaf-Surfaces. — Very rarely has the leaf a terete form and a 
 radial structure as seen in transverse section. Typically it is a flattened 
 body. One flattened surface, the Ventral, faces upw^ard or toward the 
 stem which bears it, and is ordinarily spoken of as the upper surface. 
 The under or outer surface is technically known as the lower or Dorsal. 
 By a partial twist in the petiole, the surfaces may become laterally 
 
THE STIITLKS 17:i 
 
 placed, tlu' cduvs vcrticjil. In ;i IVw leaves, tlie surfaces are normally 
 in the latter i)<)siti()n. Between the (h)rsal and ventral surfaces, there 
 are usuall\- (hll'erenees sufficient to necessitate their description sepa- 
 rately. In such descrii)ti()ns, it is better to speak of the dorsal surface 
 as being underneath rather than "helow," as the latter term may 
 confuse it with the basal region. 
 
 Anatomical Elements of the Leaf. — It has been shown that the leaf 
 originates and develops as an extension of tlie peril)lem, covered by 
 that of the dermatogen, and that it develo])s a stele which becomes 
 continuous with that of the stem. In other words, its mode of develop- 
 ment is precisely like that of a stem-branch. We have in it, therefore, 
 all the elements which characterize primary stem-structure. The 
 connection of the leaf with the stem is usually by a s})ecially arranged 
 and constructed tissue, forming a distinct organ, the pulvinus, which 
 provides an articulation designed to afford a prompt and ready separa- 
 tion of the leaf at the conclusion of the performance of its function, 
 as well as for certain movements and changes of position during life. 
 
 Just as branches of the cauline stele pass into leaf and branch, so 
 do those from the foliar stele pass laterally into its expansions, and 
 secondary and tertiary ones successively pass from them. These 
 branches are \ery frequently joined at their distal ends to others (Fig. 
 525, o), as well as at their proximal ends to the parent system. Whether 
 such is or is not the case, the result of the branching is the production 
 of a framework or skeleton which forms a support to the parenchymatous 
 tissue which fills its meshes and co^•ers its surface, the latter being in 
 turn covered by the epidermis. 
 
 Except as to the general characters which follow under leaf-classi- 
 fication, it is im])ossible to ascertain the structure of the cortex and 
 epidermis of the leaf by ordinary methods, so that this subject is 
 relegated entirely to the (lei)artment of histology. 
 
 The Stipules. — Before ])roceeding to the study of the leaf-blade, 
 which specially concerns us, certain peculiarities of the stipules, and 
 of the petiole, may be considered. The original function of the stipules 
 was probably to afford a protective covering to the bud. While this 
 function still persists, it is doubtful if that of increasing the foliaceous 
 surface has not come to be of greater importance. We should, therefore, 
 expect them to develop tissues and forms resembling those of the leaf- 
 blade, and such is the case, making them subject to the same classifica- 
 tion and terminology in those directions as will be ai)plied to the leaf- 
 blade. They ha\'e, however, certain peculiarities of their own which 
 
174 
 
 THE LEAF 
 
 here require attention. As to their presence or absence, leaves which 
 possess them are called Stipulate; those which do not, Exstipulate: 
 As they frequently fall with the expansion of the bud, there is great 
 danger that a stipulate plant may be mistaken for one which is not. 
 
 As to their duration, in relation to the leaf-bud and leaf, the terms 
 caducous, deciduous, persistent, and so on, are applied to them as to 
 the parts of the perigone. 
 
 It has been shown that the two stipules of a leaf may unite with 
 one another by either margin. They may also unite with either the 
 petiole or margin of the leaf -blade, or with the stem of the plant, in which 
 
 Fig. 473. Cordate leaf of Nymphaca, with the margins of the sinus connate at a. 474. Inter- 
 petiolar stipules of Diodia. 475. Stipulate compound leaf, with stipellate leaflets. 
 
 cases they are called Adnate. When leaves are opposite one another, 
 the two stipules between them may unite with one another by their 
 adjacent margins, forming the Interpetiolar Stipule (Fig. 474, a). 
 Especial importance attaches to this class of stipules, because of the 
 remarkable variation displayed in their subdivision and appendaging, 
 and the great value of their characters in generic classification in certain 
 families, especially in that highly medicinal one, the Rubiaceae. 
 
 In some cases, the stipules so closely resemble the foliage-leaves 
 that, together with the blade, they present the appearance of a group 
 of three leaves standing side by side. In the case of opposite leaves, 
 this sometimes makes an apparent whorl of six similar leaves, or, 
 
DURATIOS AM) RI'JTKNTION UPOX TIIK I'LAST 175 
 
 tlirouiili the union of the adjacent stipules, of four. In sncli cases, the 
 k'a\cs \vhich are sti])ulcs can be distinguished from the others by their 
 faihu-o to develop axiHary buds. The stipule is frequently transformed 
 into one or more bristles, or even strong spines, and occasionally into 
 a tendril (Fig. o()r)). 
 
 A secondary stipule, borne at the base of one of the (li\isions of a 
 compound leaf, is called a StipeUa (Fig. 475, a). 
 
 The Petiole. — Leaves possessing the Petiole; are called I'etioled those 
 wanting it are called Sessile (Fig. 478). Occasionally the petiole is 
 present, but adnate to the stem of the plant, thus appearing wanting. 
 In other cases, while quite free from the plant-stem, more or less of 
 the base of the petiole will clasp it. Such a Clasping petiole must not 
 be mistaken for a leaf-sheath, which, as we have seen, is not a true 
 petiole at all, but the development of a different part of the primary 
 leaf. 
 
 When the margins of the petiole throughout are herbaceous and in 
 continuation with the blade, the petiole is said to be INIargined or 
 Winged. 
 
 When the margins of the ])etiole are less ])r()n()unced, ])ut yet present 
 anfl elevated, so as to form a groove upon its upper siu'face, the petiole 
 is called Channelled. 
 
 Other characters of the petiole, such as its triangular or semicircular 
 form in transverse section, its relati\-e stoutness, and the character of 
 its surface, need not be specially considered. Certain special modifica- 
 tions in the function of the petiole will be considered under modified 
 leaves. 
 
 The attachment of the i)eti()le to the leaf-blade is always really 
 marginal, though by the cohesion of liasal lobes (Fig. 47i), a) it is often 
 apparently intra-marginal or even central. Basal lobes may, ui)on the 
 other hand, be adnate along the petiole, or the same appearance may 
 be produced })y the gradual difi'erentiation of petiole into blade. 
 
 Petiolar Glands. — (ilands of various forms often appear upon some 
 part of the jx'tiole, and their appearance is characteristic and of diag- 
 nostic value, as in distinguishing the species of Pnniu.s and Cassid. 
 
 Duration and Retention upon the Plant. — As the duration of the leaf 
 and its retention upon the i)lant ha\e to do in part with the nature of 
 the petiole, it may be here considered. Lca\es are Annual, and the 
 ])lants producing them deciduous, when their duration is tluough a 
 single season only, and Fvergreen, when they remain in their normal 
 and active condition into the succeeding season. Evergreen leaves 
 
176 
 
 THE LEAF 
 
 may be either biennial, the onHnary form, or perenniah Persistent 
 leaves are those which remain upon the tree, but in a dead condition, 
 being usually forced off by the growth of the following season. 
 
 The Lamina. — Coming now to the consideration of the leaf-blade, we 
 note that it is to be studied, and its varieties classified, with regard to 
 its relation to its support, its texture, surface, form — this including the 
 general outline as well as special forms of apex and base — venation, 
 margin, division, and modification of form and function. 
 
 Relation of the Leaf-base to the Plant-stem. — When a i)etiole or a 
 lamina has grown fast for a portion of its length to the plant stem, it is 
 called Adnate (Fig. 477). One whose base is heart-shaped and surrounds 
 the plant stem, whether growing fast to it or not, is called Amplexicaul 
 
 47Z 
 
 Modifications of the leaf-base: Fig. 476. Connate-perfoliate (boneset). 477. Adnate to plant stem 
 {V erhascum) . 478. Sessile (Solidago). 479. Amplexicaul (^Asler Novae-Angliae). 480. Perfoliate 
 {Oakesia). 481. Margined {PlaiUago). 482. Continuous. 483. Intramarginal-peltate. 
 
 or Clasping (Fig. 479). When the basal lobes of a clasping leaf entirely 
 surround the stem and become connate upon the other side, so that the 
 Stem appears to be growing up through a perforation in the leaf, the 
 leaf is called Perfoliate (Fig. 480). When opposite leaves are connate 
 by their bases they are called Connate or Connate-perfoliate (Fig, 476). 
 When the bases of sheathing leaves clasp the stem in such a manner as 
 to present a V-shape in transverse section, and one is superposed upon 
 another in the same manner, they are called Equitant. 
 
 Relation of the Base to the Petiole. — As to the attachment of the blade 
 to the petiole, the leaf is Peltate when this insertion is intra-marginal 
 through the connation of the edges of basal lobes. A peltate leaf may 
 be Centrally (Fig. 473), or Eccentrically (Fig. 483) peltate. When the 
 petiole changes so gradually into the lamina that it is impossible to 
 
SURFACE 177 
 
 say wliere one Ix^^ins aiul the other cinls, we say they arc Continuous 
 
 (Fis- 4S2)- 
 
 Texture. — As to their texture and consistency', the or(Hnai-y form of 
 leaf, in which it ])ossesses active chlorophyll tissue, is denominated 
 Ilerhaceous, in contradistinction to the Scarious or Scariose form, in 
 which it has a (hy and papery texture. Herbaceous leaves are ]\Iem- 
 l)ranacet)us in their ordinary form, that is, not excessively thickened, 
 Coriaceous when tough and leathery. Fleshy or Succulent when largely 
 parenchymatous, thickened, and juicy. A leaf which exhibits trans- 
 lucent dots when held against a strong light, due to the presence of 
 oil-glands, is called Pellucid-punctate. 
 
 Surface. — The surfaces of leaves may be classified in two ways: First, 
 as to the characteristics of the individual trichomes which they bear; 
 second, as to the general surface effects (Indumentum) which result from 
 the latter. The former method, although it cainiot be taken uj) in this 
 part of the work, is of very great importance in the characterization 
 of medicinal herbs and leaves, especially as it constitutes one of the 
 greatest aids to the identification of powders. The latter method can 
 only be studied with advantage by the actual examination of typical 
 specimens, it being almost impossible to characterize the different forms 
 by definition. A surface is Opaque when it is not shining or lustrous. 
 It is Glabrous when it does not possess any trichomes in such forms as 
 to detract from the smoothness of the surface. It is Glaucous when 
 covered with a waxy exudation, imparting to it a peculiar whitish 
 appearance ("bloom"), such as characterizes the surface of an ordinary 
 black grape. It is Scurfy when covered with more or less of an indumen- 
 tum in the form of granular or detached scaly masses. When the matter 
 of such masses is more thinly distributed, appearing in the form of a 
 powder rather than a scurf, the surface is called Pulverulent. 
 
 A Pubescent surface is a hairy surface which is not readily dis- 
 tinguished as pertaining to any one of the other specific classes. 
 
 If the hairs of a ])ubescent surface are very short and fine, so that 
 the consequent roughness is reduced to a minimum, the surface is 
 called Puberulent. 
 
 If a hairy indumentum is fine and of an ashy-gray color, the hairs not 
 arranged in any regular direction, the surface is Cinereous. 
 
 If the hairs all lie in one direction, are closely appressed, and ha\e a 
 shiny or silky luster, the surface is called Sericeous. 
 
 If this luster is intensified and of a strongly whitish color, whether 
 the trichomes be hairs or scales, the surface is denominated Argentcous. 
 12 
 
178 THE LEAF 
 
 Such hairs as are cai)able of producing a sericeous surface are them- 
 selves denominated sericeous or silky, even though they be in insuffi- 
 cient numbers to impart this character to the general surface. 
 
 A surface tending toward the sericeous, but not sufficiently pro- 
 nounced, is called Canescent. 
 
 When there is a dense covering of more or less elongated and matted 
 hairs, the surface is called Tomentose. 
 
 When such a covering is thin, its hairs less elongated, it is called 
 Tomentellate. 
 
 Whene there is a covering of thinly distributed, elongated, moder- 
 ately soft hairs, which are not closely appressed, the surface is Pilose. 
 
 When hairs are similarly distributed, but are elongated and coarse, 
 the surface is Hirsute. 
 
 When similar coarse hairs are rather stiff, lie in one direction, some- 
 what appressed, and particularly when each develops from an elevated 
 base, the surface is Strigose. 
 
 A surface which possesses an indumentum of scales is called Lepidote. 
 
 A surface is called Papillose when it is minutely warty, or tuberculate, 
 due usually to glands underneath the siu-face. 
 
 Wlien the indumentum consists of hard, ele^'ated points, giving a 
 roughness to the surface, the latter is Scabrous. 
 
 When such elevations are more pronounced, unyielding, and sharp- 
 pointed, the surface is Hispid. 
 
 A surface which is roughened by the presence of numerous, closely- 
 set wrinkles is Rugose. 
 
 When a surface is made up of small, blister-like elevations consisting 
 of the arching interspaces between the veins, it is Bullate (Fig. 484). 
 The opposite surface, containing the cavities of the bullae, is called 
 Cancellate (Fig. 485). 
 
 When the hairy covering is chiefly confined to the margin, presenting 
 itself in the form of a fringe of hairs, the term Ciliate is applied (Fig. 
 475). 
 
 A surface which is marked by spots differing in color from the remain- 
 der of the surface is called Maculate. If spots of any kind be small 
 and dot-like, the term Punctate is applied. 
 
 Finally, it is to be noted whether the veins or ribs, and if so which 
 of them, are prominent upon both sides or either side, or whether, upon 
 the contrary, they are depressed (called Impressed) below the general 
 surface. At times a rib or vein will not be impressed, but will yet be 
 Channelled, and may appear impressed upon casual observation. 
 
SURFACE. 
 
 179 
 
 By the outliiu' of tlic leaf, we refer to the general form of its margin, 
 wliether that he I'litire, or not. If not, then the j^eneral form of an 
 outHne is determined by connecting' the extreme points of its margin 
 with one another (Fig. 480, an ohovate onthne). It matters not, there- 
 fore, whether a leaf be entire, toothed, h)bed, or ])arted, or even if it be 
 entirely compoimd or decompound, its outline will l>e the same, pro- 
 vided a line connecting its extreme marginal points with one another 
 possess a given form. The forms of leaves on this basis may be divided 
 into three general classes — (a) those broadest at or about the middle, 
 (6) those broadest at some ])oint al)ove the middle, (c) those broadest 
 at some \nnnt below the middle. 
 
 Vc?^ 
 
 fz% 
 
 '*>« 
 
 
 
 Fig. 4S4. A bullate upiicr 8urf;i( 
 
 , A caiu'olla 
 
 ^ 
 
 Of the first class, beginning with the narrowest, \\e have the Capillary 
 or I lair-like forms, the P^iliform or Thread-shaped (Fig. 491), the Acerose 
 or Needle-shaped (Fig. 492), as those of the pine, and the Linear or 
 Ribbon-shaped (Fig. 487), all of which are so elongated that they 
 present the appearance of being about of uniform width throughout. 
 
 A leaf similar to but shorter than the linear, in proportion to its 
 breadth, without regard to the character of its apex or base, is Oblong 
 (Fig. 488). 
 
 One of similar form, but Inning a length of not more than t^\i(•e or 
 thrice its breadth, and narrower than a circle, is ()\al (Figs. 489 and 
 490), a term which must not be confoniuied with Ovate. 
 
 If an oblong or an oval leaf i)ossess a regularly rounded outline into 
 and through the ai)ical and basal portions, it is called Elliptical. \Ve 
 have, therefore, two forms of the elliptical leaf, denominated respectively 
 Oblong-Ellii)tical (Fig. 488) and ()val-Ellii)tical (Fig. 489). 
 
180 
 
 THE LEAF 
 
 A circular leaf (Fig. 493) is called Rotund or Orbicular. 
 
 Finally, we have the leaf which is broader than circular — that is, its 
 lateral diameter is greater than its vertical, and this is called Trans- 
 versely Elliptical. 
 
 
 497 
 
 Leaf outlines: Fig. 486. Obovate compound leaf of rose. 478. Linear leaf of I/ireon'a. 488. Oblong- 
 elliptical {Poterium). 489. Oval elliptical {Pyrola). 490. Imperfectly oval {Prunus). 491. Filiform 
 (Drosera). 492. Acerose (Pinus). 493. Rotund (Pyrola). 494. Ovate {ColUnsonia). 495. Reniform 
 (Asarum). 496. Lanceolate {Solidago). 497. Lancelinear (Salix). 
 
 Forms Broadest below the Middle.— Those which are broadest at some 
 point below the middle or above the middle should, in description, 
 besides being designated by the class-name of their form, have it 
 specified in some way as to about the portion at which the greatest 
 breadth occurs. 
 
 Beginning with the broadest ones, we have that which is broader than 
 long and with a heart-shaped base, called Reniform (Fig. 495). 
 
 One which possesses a length greater, but not more than two or three 
 times its breadth, is called Ovate (Fig. 494). 
 
 One of similar form, but its comparative length greater, is called 
 
FORMS niiOADEST ABOVE THE MIDDLE 
 
 ISl 
 
 Lanceolate (Fig. 496). One wliich is ovate, but with the greatest 
 l)rea(ltli at the very base, the margins not or ])ut httle curved, so that 
 it is approximately triangular, is called ])clt()i(l (Fig. 498). 
 
 One still narrower, but of similar form, Ijcaring the same relation to 
 the lance()l;it(> wliich the deltoid does to the ovate, is called Subulate, 
 or awl-shai)ed (Fig. 499). 
 
 An ovate or oval leaf whose outline, instead of being regularly curxed, 
 is made uj) of four comi)aratively straight hues is called Traj)e/.oidal or 
 Angularly-ovate. Another term which is appHed to it is Khomboidal 
 (Fig. :)()()). 
 
 Leaf outlines: Fig. 498. Deltoid {Betula). 499. Subulate (diagrammatical). 500. Rhomboidal 
 {Chekan). 501. Obovate (Lindera). 502. Oblanceolate {SoHdago). 503. Spatulate (Antennaria). 
 504. Talcsitc (Eucalyptus). 505. Inaequilatcral (//amamcZis). 
 
 Forms Broadest above the Middle. — ]\Iost of the forms just referred to 
 are i)aralleled by exactly similar forms in which the widest portion is 
 above the middle. The names for these are formed by ])refixing the 
 syllable oh to the corresponding names of the other forms; as, Obovate 
 (Fig. 501), Oblanceolate (Fig. 502). 
 
 When an. Obovate or Oblanceolate leaf possesses a broad, rounded 
 ai)ex, and a somewhat elongated lower portion, it is called Spatulate 
 (Fig. 50;^). 
 
 The outline of a leaf is greatly modified when the jxtrtioii U])on one 
 side of the midrib is longer or broader than that upon the other, giving 
 us Inequilateral, I'nequal, or Oblique forms (Fig. 505). 
 
182 
 
 THE LEAF 
 
 Wlien such a leaf has its midril) laterally (•iir\(>(l, it is styled Falcate 
 or sword-shaped (Fig. 504). 
 
 Modifications of this as regards the comparative length and breadth 
 of the leaf are Sickle-shaped and Scimeter-shaped. 
 
 Forms of the Apex. — A large numl)er of terms are employed to indicate 
 especially the form of the apex of the leaf. 
 
 si;e. 
 
 SI3. 
 
 J/4. 
 
 S/X 
 
 Forma of apex: Fig. 506. Obcordate (OxaZis). 507. Notched (Linoiieredrore). 508. Abruptly acumi- 
 nate and acute {Ailanlhus). 509. Emarginate (Pilocarpus). 510. Acute (Lonicera). 511. Abruptly 
 pointed (Ulmus). 512. Retuse. 513. Abruptly acuminate and obtuse (Fraxinus). 514. Tapering 
 {Panicum). 515. Blunt (Plantago). 
 
 Beginning with one which is inversely cordate — that is, with the 
 sinus at the Apex — we have the Obcordate form (Fig. 506). When the 
 sinus is smaller, it is called Emarginate (Fig. 509), and when very slight, 
 Retuse (Fig. 512). If the sinus be an angular one with straight sides, 
 it is called Notched (Fig. 507). If the apex be abrui)tly' terminated, 
 as though cut across in a straight line, it is called Truncate. If any 
 portion of the apex of the leaf be narrowed into a point, the leaf is 
 called Pointed (Fig. 511, etc). If such narrowing be gradual, so that the 
 point is considerably longer than broad, it is called Acuminate. If the 
 
FnR^fs OF riiE base 
 
 1S3 
 
 ac'umiiiation is preceded hy an abrupt eoiitractioii, it is distiii<,Miislied as 
 beiiiji: AI)riiptly Aeuininate (Figs. 511 and o\'.'}). 
 
 If the narrowing be very gradual and not jjreeeded by an abrupt 
 eontraetion, the ajjex is said to be Tapering (Fig. 514); if still more 
 drawn out, Attenuate. If the point of the leaf be extremely abrupt 
 and very small, it is Mueronate when soft and herbaceous, Cuspidate 
 when hard and stift', like a tooth. 
 
 Fig. 51G. Dioilalia leaf, with produced base, rounded apex, reticulate venation. 517. Apiculatc 
 apex. 518. Cuneate base (white-oak). 519. Cordate and produced base (violet). 520. Sagittate 
 base Wolygonum). 521. Aurioulate base (Aster). 522. Hastate base {Rutnex), 523. Oblique base 
 (Datura). 
 
 Any of the above-mentioned forms may be either Acute, when the 
 ultimate apex is sharp (Figs. 508, 510, and 514), Obtuse when not so 
 (Figs. 511 and 513), Blunt when very obtuse (Fig. 515), or even Hounded 
 (Fig. 51(;). 
 
 x\ leaf which has the midrib only extended into a bristle-shajjed 
 point is called Apiculate (Fig. 517), and this condition can apply to a 
 cordate as well as to other forms of the apex. 
 
 Forms of the Base.— The special forms of the base of the lcaf-i)la(le 
 yiehl a correspondingly large number of* terms. Tlu> terms cordate, 
 truncate, rounded, blunt, obtuse, acute, acuminate, and abruptly 
 
184 THE LEAF 
 
 acuminate, require no definitions in addition to those which have been 
 apphed to simihir forms of the apex. 
 
 When the two sides of the base are straight, and come to an acute 
 point, it is called Cuneate or Wedge-shaped (Fig. 518). 
 
 A base the form of which yields later to a sudden downward ])rolonga- 
 tion or acumination is called Produced (Figs. 516 and 519). 
 
 In all forms of the cordate base the greatest care must be taken to 
 specify the precise character both of the sinus and of the lobes. The 
 former must have its form or outline specified, as well as the angle 
 which it makes. It should, moreover, be carefully noted whether the 
 leaf-base at the summit of the petiole be produced into the sinus, in 
 which case it is called Intruded (Fig. 519). Sometimes the lobes of a 
 cordate base will meet one another, or even overlap. 
 
 The forms of the lobes are also capable of taking descriptive titles 
 similar to those characterizing the lamina in general. The principal 
 of such terms are Auriculate, when the lobes are rounded similarly 
 to the lobe of the human ear (Fig. 521) ; Sagittate, when pointing down- 
 ward, and acute, like the lobes of an arrow head (Fig. 520) ; Hastate or 
 Halberd-shaped, when turned outward (Fig. 522). 
 
 A base is Oblique or Inequilateral when descending lower upon one 
 side than upon the other (Figs. 521 and 523). 
 
 Venation or Nervature. — Bundles which obviously separate from one 
 another at or near or below the base of the blade, and maintain their 
 course well toward the apex or margin, are called Costae or Ribs if 
 equally prominent (Fig. 527), nerves if lateral and markedly less promi- 
 nent than one or more of the central ones (Fig. 529). 
 
 The central one, whether there be others or not, is the Primary or 
 Midrib (Fig. 524, a). Branches or ribs or nerves are called A'eins, and 
 they are distinguished as Secondaries (6) when departing from the mid- 
 rib, Tertiaries (c) when departing from Secondaries, and so on. In 
 palmately veined leaves, the central is called the IMiddle Primary, the 
 other, the Lateral Primaries. The middle one is here also called the 
 midrib, if distinctly stronger than the others. Secondaries of lateral 
 ribs or nerves must be especially so designated in description. Very 
 small veins are called Veinlets. 
 
 The greatest importance in descriptive terminology pertains to the 
 classification of leaf-\'enation, owing to the frequency with which leaves 
 must be identified in such a fragmentary state that there is little beyond 
 the surface and venation, with possibly a portion of the margin, to 
 assist us. 
 
VENATION OR NERVATURE 
 
 185 
 
 The forms all fall within two principal classes, which, in general, 
 characterize respectively the monocotyledons and the dicotyledons. 
 The former hears its ])rincipal veins more or less ])arallel with one 
 another, and these are munerons. Snch lea\es are called I'andlcl- 
 veined (Fig. 52G). 
 
 Venation or Ncrvature: Fig. 524. Pinnateiy veined leaf of Castanea: a, midrib; b, secondaries; c, 
 tertiaries. 525. Reticulate leaflet of Pilocarpus: a, anastomosis of secondaries. 526. Parallel-veined 
 leaf of Convallaria. 527. Flabellately costate leaf of Plantago. 528. Digitately veined leaf of Cercis. 
 529. Costinerved leaf. 
 
 In the second form there is hut one, or a comparati\'ely few t)ri<,nnal 
 veins, and these give rise to successively developed branch systems, 
 the whole forming a network or Reticulum. Such leaves are called 
 reticulated or Xetted-veined (Fig. 524, etc.). These veins may or may 
 not anastomose or intercommunicate at their distal ends. When they 
 
186 THE LEAF 
 
 do, the term Reticulate is applied to them in a special or restricted 
 sense (Fig. 525). In leaves of the last-named class the details of the 
 method of intercommunicating are very important. Thus, in some cases, 
 the end of each secondary is arched upward into the secondary next 
 above (Fig. 525). In such case it is important to note the comparative 
 distance from the margin at which the communication takes place and 
 the angle at which the two meet, as these characters are always constant 
 in the same species. In other cases the secondaries (or the ribs, as in 
 Fig. 568) are directly connected by straight and parallel secondaries 
 or tertiaries, or in still others (Fig. 516) by an irregular intervening 
 network of small veins. Secondaries connected by the first method 
 are usually also connected near the base with the midrib by a number 
 of curved tertiaries. 
 
 When the principal veins or nerves of a leaf are straight, it is called 
 Rectinerved; when curved, Curvinerved. The latter term refers to a 
 regular and characteristic curve, not to a crooked course. Some leaves 
 are characterized by possessing waving or crooked nerves or veins. 
 
 Two great classes of netted-veined leaves are recognized, the one in 
 which there is a main Rachis or midrib, from which secondaries 
 extend regularly toward the margin. This form is knowp as the Penni- 
 nerved or Pinnately veined leaf (Fig. 524), The number of pairs of 
 secondaries, whether they originate exactly opposite to each other or 
 somewhat irregularly, is within fair limits characteristic of the species, 
 and should be stated. The same is true of the angle at which they 
 radiate from the midrib. In the case of additional ribs or nerves of 
 such a leaf, their number and stoutness as compared^with the midrib, 
 their comparative length and the position which they take in the leaf 
 are all important. The second great class of netted-veined leaves is 
 that in which a number of approximately equal ribs ra^aliate from the 
 basal region. Such leaves are known as Palmately>or Digitately 
 Veined (Figs. 527 and 528). There are, of course, many forms of inter- 
 grading (Figs. 529 and 568) between such leaves and pinnately veined 
 leaves with secondary ribs or nerves. Sometimes the nerves start from 
 the very base of the leaf, in which it is called Basinerved (Fig. 528) ; 
 at others from the lower portion of the midrib, when it is called Costi- 
 nerved (Fig. 529). When the ribs or nerves are manifestly continued 
 downward into the petiole, the leaf is called Flabellately nerved (Fig. 
 527). 
 
 The Leaf-margin. — The manner in which the leaf-margin comes to 
 deviate from an entire condition has already been indicated. Three 
 
THE J.KAF MAIiCIN 
 
 187 
 
 special forms of tootliiiii;- arc i-cconni/cd, in accordance with llic form 
 and direction of the teetli. When the hitter jx.int in an outward direc- 
 tion the margin is caUed Dentate (Fiji;. ")."54); wlieii toward the ai)ex of 
 the leaf, Serrate (Fig. I'^'.V^). When, instead of l)einij; pointed, the teeth 
 are rounded, the margin is Crenate (Fig. 530). 
 
 Margins: Fig. 530. Crenate {Daliharda) . 531. Doubly serrate, the teeth appressed (Ulmus). 532. 
 Obsoletely serrate (.Gaultheria) . 533. Serrate. 534. Dentate (Viburnum). 535. Serrulate (Vibur- 
 num). 530. Ropand (Hamnmclis). 537. Sinuate. 
 
 Diminutives of these terms, indicating that the teeth are very small, 
 are Denticulate, Serrulate (Fig. 535), and Cremilate. To any of these 
 terms tiie word "Minutely" may be prefixed as indicating that the 
 teeth are still smaller. Of each of these three ])riiici])al forms there 
 are a number of sub-forms. 
 
 When the teeth bear smaller or secondary teeth, the word " Doubly" 
 is prefixed (Fig. 531, (l()ubl>- serrate). 
 
 When serrate teeth ha\-e their ])()ints \-ery stronglx' directed toward 
 the apex or ai)pearing as though pressed inward against the margin, 
 they are called .Xpprcssed (Fig. o.n , partly). They may even be 
 Incurved. When, ui)on the other hand, the ends of the teeth are turned 
 outward, they arc called Salient. When the points of the teeth are very 
 
188 
 
 THE LEAP 
 
 fine and })ro(luced in tlie form of bristles they are called Spinulose (Fig. 
 524). 
 
 When a margin shows indications of being dentate, serrate, or crenate, 
 but the teeth are not distinctly pronounced, the adjective Obscurely 
 is prefixed. For this word that of "Obsoletely" is substituted when 
 the leaf possesses a relationship such as to make it probable that its 
 ancestral forms were more strongly characterized by this condition 
 (Fig. 532). 
 
 Fig. 538. Pinnatifid (Pedicularis) . 539. Palmatifid (gooseberry). 540. Laciniately divided (but- 
 tercup). 641. Slightly revolute. 542. Strongly revolute (i?o.sOTari>ius). 543. Lobed, the lobes acute, 
 the sinuses obtuse (_Quercus). 544. Both lobes and sinuses obtuse {Sassafras). 545. Lobes obtuse, 
 sinuses acute (.Hepatica). 546. Incisely parted (Geranium). 
 
 When the teeth and their sinuses are all connected in such a way 
 that the margin represents a wavy line, the latter is called Hepand or 
 Undulate, or Sinuate (Figs. 536 and 537). When a leaf is so deeply 
 toothed that the sinuses reach well toward the middle portion (Figs. 
 543 to 545) the term Lobed is substituted for those above defined. 
 
 When the division, by a sharp sinus, extends more than half-way to 
 the middle, yet not very near to the midrib, it is called Cleft (Fig. 539). 
 
 When reaching almost to the midrib (Fig. 538) or to the base in case 
 of a digitate leaf (Fig. 546), it is called Parted, and when all the way, 
 Divided (Figs. 540 and 559). The divided leaf is, however, not the same 
 as the compound leaf, inasmuch as the separation of its blade into 
 distinct leaflets is not complete. (Compare Figs. 547 and 555.) 
 
 The cleft, parted or divided leaf, is either Pinnatifid (Figs. 538, 556, 
 
THE COMPOUND LEAF 189 
 
 etc.) or Paliiiatifid ( Fii^s. 540 and 540), accor(lin,ti; to tlic cliaractcr of Its 
 venation. In all forms of lobed, cleft, parted or <li\idc(i leaves, it is 
 necessary that the detailed characters of the lohes and of the siinises 
 should be specified. The lobe may be acute, while the sinus is rounded 
 (Fig. 543), or the reverse may be true (Fig. 545), or both may l)e acute 
 or both obtuse (Fig. 548). The sinuses as well as' the lobes frequently 
 possess definite and characteristic outhnes, indicated by terms such 
 as have already been defined in connection with the leaf. When the 
 teeth and sinuses are outUned by straight hues and sharp terminations, 
 as though notched out by a pair of scissors, the margin is said to l)e 
 Incised (Figs. 540 and 546). When the divisions and sinuses are long 
 and narrow in addition to being incised, it is called Laciniate (Fig. 540). 
 When the margin of a leaf is turned downward or backward or rolled 
 backward, it is said to be Revolute. Ordinarily the revolution is very 
 slight (Fig. 541), but occasionally, particularly upon drying, it will be 
 found extreme, each half of the leaf forming a roll, the two meeting 
 back of the midrib (Fig. 542). 
 
 Before proceeding to speak of the forms of compound leaves, it 
 should be stated that when one of the terms above defined (and the 
 same is generally true of descriptive terms used in other parts of the 
 work) terminates in the ending ate or oid, it sometimes indicates that 
 the condition tends toward but does not quite reach that named by 
 the term to which the ending is appended. For example, triangulate 
 means inclining toward triangular. The student will also note that 
 between nearly all the forms of leaves and the characters indicated by 
 the terms above defined, there are intermediate forms connecting them 
 with others. 
 
 Inasmuch as it is necessary in description for such forms to be 
 indicated, the method is resorted to of employing the two terms con- 
 nected by a hyphen. Thus, Lance-ovate, or Ovate-lanceolate (Fig. 
 497) indicates that the form is intermediate between lanceolate and 
 ovate; crenate-flentate and serrate-dentate are similar illustrations. 
 
 A similar intermediate condition is sometimes indicated by prefixing 
 the term .sub, thus sub-cordate, sub-sessile, sub-acute. Other inter- 
 mediate terms very commonly employed are acutish and ol)tnsish. 
 
 The Compound Leaf.— lii the lohed leaves which we ha\c already 
 examined, even the most (leei)ly dixided of them, the lobes are seen to 
 be connected with one another at the base by ])ortions of the conmion 
 blade, so that a complete division of the blade into separate parts has 
 not taken place. In the leaves which we are now to examine, such 
 
190 
 
 THE LEAF 
 
 se])arati()n has occurred, and the lamina has become divided into a 
 number of distinct secondary bhides (Figs. 54S, .554, etc.). Leaves of 
 this kind are called Compound, and their divisions, Leaflets. 
 
 If the leaflets are themselves compound, the leaf is Decompound. 
 Decompound leaves are spoken of as once compound, twice compound, 
 etc., according to the number of successive divisions. Leaflets may be 
 distinguished from leaves by the fact that no buds are found in their 
 axils. Leaflets are subject to the ai)i)lication of the same descriptive 
 terminology as leaves. 
 
 Leaflets of the first division are called Pinnae, those of subsequent 
 divisions, Pinnules. 
 
 The continuation of the petiole passing up among the leaflets, that is 
 the midrib of the compound leaf, is the rachis (6, Fig. 475). 
 
 Fig. 547. Palmately compound leaf {Aesculus). 548. Palmately trifoliolate leaf (Trifolium) . 549. 
 Pinnately trifoliolate leaf (.Lespedeza) . 550 and 551. Unifoliolate compound leaves of orange. 
 
 When, as in Fig. 548, the compound leaf has no rachis, its division 
 being on the same plan as the lobing of the palmatifid leaf, it is Palmate, 
 or Palmately compound. When the rachis does exist, corresponding to 
 the pinnatifid type (Figs. 549 and 554), the leaf is Pinnate, or Pinnately 
 Compound. 
 
 Before proceeding to define the distinct forms of the two classes, we 
 note that it is not always possible to identify them with readiness. For 
 example, the ancestral form of the leaf of the orange was pinnate, but 
 at the present time we find that only the terminal leaflet remains, 
 there being usually at the base more or less of an indication of the two 
 lateral leaflets which once existed (Figs. 550 and 551). Such a leaf 
 cannot, therefore, be properly designated as simple, and we designate 
 it as a Unifoliolate compound leaf. 
 
 Compound leaves with three leaflets, usually designated as Trifolio- 
 late, frequently give us considerable difficulty in determining whether 
 
77//'; COMl'Oi'MJ Lh'AF 
 
 191 
 
 tlu'v arc i)iiiiiatc'ly or ])almatoly coinpouiKl. Tlic (iiu'stioii is to l)e 
 decided in aeeordaiiee with tlie i)()iiit a( wliieii disarticulation of the 
 tenniiial leaflet occurs. If ])alniate, the \):\>v of the blade must ))e the 
 point at which the three petioles separate, so that when disarticulation 
 occurs no rachis will remain extending l)ey()nd the j)oint of attachment 
 of the two lateral leaflets (Fig. 548). In the })innate form such a rachis 
 
 Fig. .'io2. Triternate leaf. 553. Pedatetloaf (violet). 554. Pari-pinnate leaflet of Gcdilschia. 555. 
 Impari-pinnate leaf of rose. 556. Millifoliolate leaf of Achilldea 557. Interrupteilly-pinnate leaf 
 of Aqrimonia. 558. Runcinate leaf of dandelion. 559. Lyrate leaf of barbarea. 
 
 (Fig. 549, a), although frequently very short, does exist. In the family 
 Leguminosae, the question of whether a leaf is pinnately or palmately 
 trifoliolate is of fundamental importance in classification. 
 
 A three-parted j)almately com])ound or divided leaf is called Ternate; 
 a five-parted one Quinate, a se\en-parted one Se])tate. 
 
 A palmatifid (or i)alinate) leaf, with very narrow di\ isions, is called 
 Pedate (Fig. 553). 
 
192 THE LEAF 
 
 If the divisions of such a leaf are similarly compound or divided, 
 appropriate terms are formed, such as Bi-ternate (Fig. 552), Tri-ternate, 
 and so on. Similarly named sub-divisions of the pinnate form exist, 
 the bi-pinnate (Fig. 563), tri-pinnate (Fig. 556), and so on. 
 
 These terms are also sometimes applied to the similar divisions of 
 pinnatifid leaves. Just as we have found that the number of pairs of 
 primary veins of the simple leaf is generally characteristic of the species, 
 so we find that the number of pairs of pinnae, technically known as 
 Jugae, is equally so. This number, therefore, should always be stated, 
 the leaf being designated as Bi-jugate, Tri-jugate, Multi-jugate and 
 so on. 
 
 Two classes of pinnate leaves are recognized, in accordance with 
 their termination in a pair or in a single terminal leaflet. Those ending 
 in a pair (Fig. 554) are called Pari-pinnate, Even-pinnate, or Equally- 
 pinnate, the others (Fig. 555) Impari-pinnate, Odd-pinnate, or 
 Unequally-pinnate. 
 
 When the divisions of a pinnate or a pinnatifid leaf are alternately 
 large and very small (Fig. 557), it is called Interruptedly-pinnate or 
 Pinnatifid. 
 
 When the leaflets or divisions are turned backward so that they 
 point more or less in the direction of the base (Fig. 558), the leaf is 
 Runcinate. 
 
 When the terminal division is very much larger, especially broader, 
 than the lateral, the leaf is Lyrate (Fig. 559). 
 
 Modified Leaves. — Coming now to consider the subject of character- 
 istic modifications in the form and function of the leaf, we note that 
 some of them pertain to the entire leaf, others to its individual parts. 
 We also note that in some of the modifications the entire leaf or one of 
 its parts retains the ordinary functions of absorption and assimilation, 
 the new function being added thereto either by partial change of the 
 entire leaf, or the complete modification of one or more of its parts, 
 while at other times the original functions are entirely lost. 
 
 Carnivorous Leaves. — The function of absorbing and assimilating the 
 ordinary forms of nutriment is sometimes supplemented by that of 
 absorbing and assimilating animal tissue. In this case the leaf pro- 
 vides special forms of apparatus for enticing, intoxicating, or mechan- 
 ically catching, killing and digesting the animal, commonly an insect. 
 
 The Pitcher Plant. — One of these forms is illustrated in the pitcher 
 plant (Fig. 560), in which one portion of the leaf becomes converted 
 into a vessel containing liquid of variable origin and complex compo- 
 
ETIOLA TED LEA YES 
 
 193 
 
 sition. U])()n the outer portion of the ])itc'her a Hue of ghiiiduhir tissue 
 stretches downward. The insect feeds ujjward along this line of secre- 
 tion, which so changes its nature toward the toj) of the pitcher, that 
 by the time the insect reaches that point he is more or less intoxi- 
 cated, and on crossing the margin, or quickly thereafter, falls into the 
 liquid and is drowned, digestion prom])tly occurring by means of 
 enzymes excreted into the liquid by special glands located upon the 
 inner face of the i)itchcr. 
 
 Fig. 560. Modifitd (pitcher) leaf of NepeiUhcs. 561. Modified leaf of Die 
 
 The Venus' s Fhj-fntp. — Another form is the well-known ^'enus's 
 fly-trap (Fig. 5()1), which secretes a nectar by certain glands which 
 surround its margin. The insect, alighting upon this point, is instantly 
 seized through the sjiasmodic coming together of the two lateral halves 
 of the leaf, which act precisely like the jaws of a trap. Digestive fluids 
 are then immediately poured forth from special glandular tissues on 
 the leaf-surface and digestion and absorption take i)lace. That the 
 nutrients thus absorbed are of service to the ])lant has been proved by 
 elaborate experiments, in which the eflfects of such feeding have been 
 estimated by comparing their re})roduction with that of other similar 
 plants, similarly treated in all respects except that they were dei)ri\ed 
 of this form of food. 
 
 Etiolated Leaves. — In other cases, the ])lant being nourished by 
 means of fully prepared nutrients absorbed from other leafy plants 
 (host-plants) upon whicli they are parasitic, the leaves lose the chloro- 
 phyll tissue uj)()n which their ordinary functions (lei)cnd, and arc 
 known as Etiolated leaves. They become reduced in size and scale-like 
 in form. 
 13 
 
194 
 
 THE LEAF 
 
 Plants which grow in excessively dry or desert regions, and Avhich 
 are thus ^'ery liable to suffer from excessive evaporation, ordinaril}- 
 have their leaves modified in some way so as to guard against this 
 
 Fig. 562. Phyllodiuni of Aaicia. 503. Leaf of Acacia with blade present. 564. Loaf of Eichomia 
 with inflated petiole. 505. Cirrhose stipules of Smilax. 566. Aculeate leaf of Rubus. 567. Cirrhif- 
 (Tous leaf of pea. 568. Leaf of Tococa, its inflated petiole the home of ants. 569. Cirrhose petiole 
 of Clematis. 
 
 tendency, and are called Xerophytic. They may become merely 
 reduced in size or may be otherwise modified, so as to reduce the 
 amount or the degree of activity of their epidermal tissue, or they 
 
FLORAL LEAVES OR BRACTS 195 
 
 may disappear altogether, or become transformed into organs of a 
 different character. In one of tliesc forms the leaf becomes converted 
 into a s])ine, or a grou]) of s])ines, each consisting of one of the teeth. 
 In this condition the leaf serves an important function in protecting 
 the plant against destruction by desert animals. 
 
 Phyllodia. — At other times the blade (Fig. 5().'^, a) entirely disappears, 
 a false blade (Phyllodium, Fig. 5()2), of much less activity as an evapor- 
 ating organ, becoming formed by the flattening out or exi)ansion of 
 the petiole (Fig. 553, c). A phyllodium is readil>- distinguished from a 
 leaf-blade in that its broad surfaces are directed laterally instead of 
 vertically, as in the true lamina. 
 
 Leaves as Floating Organs. — Leaves or their petioles frequently 
 become luodified into floating organs in aquatic i)lants, as in the case 
 of the bladdery-inflated petioles of the Eichornia (P'ig. 504). 
 
 Somewhat similar inflated organs exist upon the petioles of some 
 plants and serve as the homes of colonies of ants, which are efficient in 
 protecting the plant against the attacks of certain animals (Fig. 568, a). 
 
 Leaves as Climbing Organs. — The office of climbing is frequently 
 ])crf()rnH'd by a portion of the leaf. In some cases, as the Clematis 
 (Fig. 569), the petiole of the leaf becomes twining for this purpose. 
 At other times the apex of the rachis (Fig. 567) becomes a tendril, 
 either simple or branching, while at others the entire leaf becomes thus 
 modified. In the Smilax (Fig. 565) it is the stipule which is thus 
 changed. In other cases (P'ig. 566) climbing is effected by means of 
 hooks develoi)ed u])on some ])ortion of the leaf. 
 
 Floral Leaves or Bracts. — Besides protecting the i)laut by becoming 
 converted into spines or spine-bearing organs, as above described, the 
 leaf is subject to various other modifications having this object in view. 
 Ucfert-nce lias already been made to such modifications in the form of 
 bud scales. For the i)rotection of the flower exist the epicalyx and such 
 scales, called Floral Leaves or Bracts, as have been described in our 
 opening account of the flowers of the willow. 
 
 Floral leaves or bracts do not always exist merely for jjurposes of 
 protection. In very many cases they are functionally a i)art of the 
 flower structure, surrounding either single flowers or clusters of 
 flowers, and ser\ing by their large size or brilliant coh)rs, or 
 both, to attract insect-\isits, i)rccisely the same as has be(Mi described 
 in reference to the i)erigone. Through the floral bracts thus modified, 
 we get a direct transformation into the ])arts of the perigone, as has 
 already been sufficiently explained. It is also important to note that 
 
196 THE LEAF 
 
 a direct relation is to be traced between the definite arrangements of 
 foliage and floral leaves, as will be considered under Phyllotaxy, and 
 the arrangement of the parts of the flower itself; so the characteristics 
 or praefloration are seen to be directly dependent upon the phyllotaxy 
 and praefoliation. 
 
 Phyllotaxy. — In view of the established fact that the development 
 of the branches follows that of the leaves, it becomes clear that the 
 arrangement of the latter determines the entire symmetry of the 
 plant, with all the far-reaching consequences in connection with both 
 vegetation and reproduction. Certain definite laws of phyllotaxy 
 having been ascertained, the forms resulting become, in their different 
 manifestations, of nearly fundamental importance in classification and 
 in diagnosis. 
 
 The Whorled Arrangement. — We find that either one or more than one 
 leaf is developed from a node. In the latter case the arrangement is 
 called Verticillate or Whorled, and the circle a Whorl or Verticil. If 
 the Whorl contain but two members, they are called Opposite — that 
 is, the centers of their points of insertion are separated by one-half the 
 circumference, or their Divergence is 180 degrees. Usually the other 
 nodes are similarly clothed, except that in all of the higher plants the 
 leaves of each pair Decussate with those of each adjacent pair — that is, a 
 leaf of one whorl is over the center of the sinus of that next below (Fig. 
 570). Four vertical rows (Orthostachies) of leaves thus appear upon 
 such a stem (Fig. 573). If, instead, there be three leaves to the whorlj 
 six orthostachies will result; if four, eight; and so on. It frequently 
 happens that the number of leaves in the upper or lower whorls will 
 contain only half the number of leaves in the others, and still higher 
 up the whorled arrangement may be lost, the leaves becoming arranged 
 as in the form next considered. 
 
 The Alternate or Spiral Arrangement. — By the other arrangement the 
 nodes produce solitary leaves, so that each leaf is successively produced 
 at a higher level. If a line be traced from the point of origin of one 
 leaf to that of the one next above, and continued in the same direction, 
 so that it exactly meets the point of insertion of another, and then of 
 another, and so on, it will at length meet one exactly over the point of 
 starting — that is, a second leaf in the same Orthostachy (Fig. 571). 
 It will then be found that the line followed is a spiral, which has passed 
 once or more around the stem. Such a spiral is called a Cycle, and if its 
 line be continued, it will form other similar cycles above and below. It 
 is observed that a cycle will be limited by two adjacent leaves of one 
 
THE ALTERNATE OR SPIRAL ARRANGEMENT 
 
 197 
 
 Ortliostacliy. Thus, if loaf No. 4 is the next in tlie orthostachy, to 
 which leaf No. 1 belongs (Fig. 574), three lea^■es will belong to that 
 cycle. A cycle containing three leaves makes but one turn of the stem. 
 A cycle is expressed in the form of a fraction, its numerator indicating 
 the number of times it encircles the stem, its denominator the number 
 of leaves which it includes, so that the cycle last described must be 
 indicated by the fraction one-third. The angular divergence of its leaves 
 is 120 degrees. If the next leaf in the same orthostachy as No. 1 be 
 No. G (Fig. 572), then that cycle will contain five leaves. A cycle 
 containing five leaves makes two circuits of the stem, so that its exponent 
 
 Fig. 570. Decussating opposite leaves. 571. Alternate or spiral leaf-arrangement. 572. Diagram 
 of the same, the f, arrangement. 573. Diagram of 570, showing its 4 orthostachies. 574. The j spiral. 
 575. The ,; spiral. 
 
 will be two-fifths. If the second leaf of the orthostachy were No. 9, the 
 appropriate fraction would be three-eighths, the cycle making three 
 turns and containing eight leaves (Fig. 575). It will thus be observed 
 that these fractions form a series, in which each possesses a numerator 
 equal to the sum of the numerators of the two preceding and a denom- 
 inator equal to the sum of the denominators of the two preceding. No 
 cycles occur among the higher plants with which we are concerned, 
 which can be indicated by any fraction not thus formed. 
 
 Noticing these fractions still further, we obserxe that tlic (Iciioiiii- 
 nators will indicate the number of orthostachies upon the stems which 
 
198 THE LEAF 
 
 they represent, and that the value of the fraction will represent the 
 divergence of, or part of a circle between, any two leaves adjacent in 
 the cycle or spiral — that is, the number of degrees between such leaves 
 will equal that fractional part of 3()0 degrees. 
 
 Antidromy. — As to the direction which the spiral takes, it may be 
 either from right to left or from left to right. It is supposed that each 
 kind of plant, at least of the higher classes, produces two forms or 
 "castes," depending in some not yet perfectly determined way upon 
 the relative positions of the respective ovules from which they originate. 
 The tendency of these two castes to manifest their growth or develop- 
 ment in opposite directions has been called Antidromy. Among numer- 
 ous other phenomena attributed to antidromy is this starting of the 
 leaf-spiral in opposite directions in plants of the two castes of any 
 species with this form of phyllotaxy. 
 
 The Scattered Arrangement. — Occasionally, leaves appear to be 
 irregularly disposed upon the stem — that is, they are not whorled, nor 
 does the law of alternate phyllotaxy appear to apply to them. This 
 arrangement is called Scattered, and the explanation is dift'erent in 
 different cases. 
 
 Tufted Leaves. — When a stem is so shortened that the leaves are 
 crowded upon it in the form of a regular rosette, as in the house-leek, 
 the arrangement is called Tufted. 
 
 Fascicled Leaves. — ^When similarly short, but the leaves few and 
 irregularly crowded in a little bunch, the arrangement is Fascicled. 
 
 The two regular forms of leaf arrangement above described can be 
 traced in greater or less perfection through floral bracts and involucres, 
 and into and in many cases partly or wholly through the flower itself. 
 While such arrangement in the flower is in many cases entirely verti- 
 cillate and in most cases partly so, it has been quite clearly shown that 
 many flowers have certain of their parts arranged ui)on the spiral ])lan. 
 
CllArTKIJ XVll 
 ANTIIOTAXY 
 
 The aiTangcment of flowers is called their Aiithotaxy, and this name 
 is also ap})lied to the study of inflorescences. 
 
 The Inflorescence. — That part of a stem or branch which bears the 
 flowers, or the flower when solitary, is more or less distinctly modified 
 in form, surface, modification of its leaves, extent and character of 
 branchinff, and frequently also in the direction taken in the arrange- 
 ment of its parts. In connection with its flowers it is called the Inflor- 
 escence. 
 
 The stem of an Inflorescence, that is, the portion which is below its 
 lowest point of branching or flowering, or below the flower when solitary, 
 is called the Peduncle {a in Figs. 57() and 583). This name is also 
 applied to the corresponding portion of a branch of an inflorescence if 
 that branch bear more than one flower, it being in that case a Secondary 
 Peduncle (Fig. 584, d). 
 
 The Rachis. — If the peduncle is continued above its first point of 
 branching, in the form of a central support along which the succeeding 
 branches or the flowers are arranged, this portion is called the Uachis 
 (Figs. 583 above a and 58(5, a). 
 
 The Scape. — A peduncle which rises directly from or near the ground 
 is called a Scape (Fig. 57(5, a). 
 
 The Pedicel. — The stem of one of the iii(h\idual flow(>rs of an inflor- 
 escence of more than one flower is called a JVdicel (r, in Fig. 584). A 
 flower or an inflorescence may be devoid of i)e(licel or ])eduncle, when 
 it is Sessile. 
 
 The arrangement of the infloresc(Mice-lea\es and their lloral branches, 
 while based upon the phyllotaxy, and traceable thereto in most cases, 
 exhibits more or less real or apparent departure therefrom, and calls 
 for special designations and classification. 
 
 The Determinate form of Anthotaxy. — The forms of flowering are 
 di\i(led into two scries in accordance with the a])ical or lateral location 
 of the initial fiower — that is, the flower which is first in order of develop- 
 ment. If the terminal bud develop into a flower (Fig. 57(5) its further 
 
200 ANTHOTAXY 
 
 extension is impossible, except by the rare and abnormal process of 
 Proliferation. Inflorescences so limited are called Determinate or 
 Definite. 
 
 Vertical Extension by the Branches. — Although vertical extension of 
 the original stem of a determinate inflorescence is not possible, it can 
 take place through the branches, the same as in other sympodia. The 
 effects of such development are the same as in other forms of sympodial 
 growth in which there is a transformation of the apex of the original 
 stem — as, for instance, in our explanation of such a mode of develop- 
 ment of the tendril (Fig. 431). To apply this principle in the case of an 
 inflorescence, we have only to assume a flower developed at the tip of 
 every branch in Figs. 433 to 435. Flower a would develop first; h, 
 although the second in order, and hence a branch, and afterward c, 
 would be more elevated, and would thus seem to prolong the vertical 
 extension of the stem. The development being successively by nodes 
 whose original points of origin were successively lower than that of the 
 terminal flower, is structurally and really Descending or Basipetal, 
 even though by the upward growth of the successive branches they be 
 at successively higher levels, the order apparently in the opposite 
 direction. By the development at each node of a pair of opposite 
 branches we get the apparent bifurcating or dichotomous form (Fig. 
 435). If but one branch grow from a node, and these successively from 
 right to left, the zig-zag or Flexuose form of rachis is produced (Fig. 
 433), and if constantly from the same side, or apparently so, the Cir- 
 cinate (Fig. 434). 
 
 The descending or basipetal nature of the definite inflorescence is 
 clearly shown when the successive branches remain short, each succes- 
 sively developed flower remaining at a lower level than that which 
 preceded it (Fig. 581). 
 
 The Centrifugal Form. — Instead, however, of assuming either of these 
 two states, in which the flowers remain at different levels, the branches 
 may radiate and elongate to different degress, ceasing their elongation 
 when their flowers have been brought to a uniform height, so that a 
 more or less flat-topped inflorescence results, the order of development 
 being from the center outward, or Centrifugal, as in the branches of 
 Fig. 584. 
 
 Cymose Inflorescences. — This form represents the true Cyme, and 
 because of their relationship to it this entire series of inflorescences is 
 often denominated the Cymose. It will thus be seen that in different 
 forms of the cymose inflorescence, we may have the flowers all brought 
 
THE INDETERMINATE FORM OF ANTIIOTAXY 
 
 201 
 
 at length to a uiiiforni level, those of successively later (leveIo])ment 
 brought to successively higher ])oints, or left at successively lower 
 le\-els. This fact demonstrates that the cyniose or descending nature 
 of an inflorescence cannot be determined by noting the relative heights 
 of the flowers themselves, but only by noting the order of their 
 development. 
 
 JS2 
 
 MJ. 
 
 J^SJ. J86 
 
 Fig. 576. Scapo.sc 1-flowored peduncle of tulip. 577. Corymb of Crataegus. 578. Head of Cepha- 
 lantll^ls. 579. Umbel of ^Lscifpias. 580. Secund raceme of fiicucw/^o. 581. A descending inflorescence. 
 582. Ordinary raceme. 583. A spike. 584. Compound cyme of Saponaria. 585. Globular spadix 
 enclosed in spathe of Spathyema. 586. Cylindrical spadix of Acorus. 
 
 The Indeterminate Form of Anthotaxy. — In the second series, the first 
 flower to develop is structurally the lowest of the cluster, the succession 
 being upward. Ascending or Acropetal (Figs. 582 and 583). If the 
 successive branches develop less rapidly than their predecessors, 
 the result is again a flat-topped inflorescence, with the development 
 from the outside to center, or Centripetal (Figs. 577 and 579). The 
 branches and flowers may be separated on obvious peduncles and 
 pedicels, or these may be not apparent, the flowers being sessile. In 
 accordance with the characters above explained, we obtain the following 
 simple forms of anthotaxy: 
 
202 ANTHOTAXY 
 
 Series 1 
 
 Ascending, Acropetal, Indefinite, Indeterminate, Centripetal, or 
 Botryose Forms. 
 
 A. With the rachis not elongated. 
 
 1. The Capitulum or Head, with the flowers, and branches, 
 
 if any, sessile or so regarded (Fig. 578). 
 
 2. The Corymb, with the rachis manifest, though short, and 
 
 its pedicels or branches elongated so as to produce a 
 flat-topped inflorescence (P'ig. 577). 
 
 3. The Umbel, similar to the Corymb but with the rachis 
 
 not manifest, so that the pedicels or branches all appear 
 to start from one point at the summit of the peduncle 
 (Fig. 579). 
 
 B. With the rachis elongated. 
 
 4. The Spike, with the flowers, or branches, if any, sessile or 
 
 so regarded (Fig. 583). 
 
 5. The Catkin or Ament, a spike with slender rachis and 
 
 bearing usually staminate or pistillate flowers, crowded 
 and subtended by scales (Figs. 8, 11, and 15). 
 
 6. The Raceme, similar to the spike or ament, but having 
 
 the flowers pedicelled (Figs. 580 and 582). 
 When either the head or spike possesses a thick, fleshy, 
 rachis it is called a Spadix (Figs. 585 and 586). 
 
 Series 2 
 
 Descending, Basipetal, Definite, Determinate, Centrifugal, or Cymose 
 Forms. 
 
 1. The Glomerule, corresponding to the head in all respects 
 
 save that the central flower first develops. 
 
 2. The Fascicle, similar to the glomerule except that the 
 
 flowers are few and loosely clustered. 
 
 3. The Cyme, similar to the corymb or umbel, save that 
 
 the central flower is the first to develop (Fig. 584). 
 
 4. The Scorpioid Raceme. Similar to the raceme, except 
 
 that each successive node and flower upward is lateral to 
 that next below. The apex of the scorpioid raceme is 
 circinately coiled (Fig. 434). 
 
THE ANTIIODIUM 203 
 
 Compound Inflorescences. — Before ])r()ceeding to consider certain 
 speciul forms and inodificatioiis of the inflorescences above defined, 
 it should he remarked that most of the forms may be comi)ouiid. By 
 this we mean that the chister is made up of a number of l)raneiies whose 
 order of devel<)i)ment is the same as that of the elements of which they 
 are composed. That is, the raceme may i)ossess a number of branches, 
 each of wliicli is a smaller or secondary raceme, or if not a raceme, at 
 least a small inflorescence of the ascending or centripetal form. Similarly, 
 an umbel may be made up of branches, each of which is a smaller umbel, 
 the Umbellule. A cyme will be made up of cymules, and so on. A 
 Panicle is a compound raceme which assumes the form of a pyramid. 
 Any form of inflorescence not a true panicle, but assuming the shai)e 
 of one, is styled Paniculate. 
 
 Complex Inflorescences. — Complex forms of inflorescence differ from 
 the compound in that the order of development of the several flowers 
 upon a branch is of a different kind from that of the several branches 
 themselves. For exmaple, the ThjTsus or Thyrse is a paniculate form 
 in which the lowest branch is the first to develop flowers, so that the 
 order of development of the branches is ascending, but within a branch 
 the terminal flower will be the first to develop, so that the order of 
 development of its flowers is descending. In the same way, each 
 branch of an umbel may terminate in a head; or we may have a fascicle, 
 each branch of which is a raceme. 
 
 The Anthodium. — The term Anthodium has already been defined in 
 considering the forms of the fruit, under Multiple or Collective Fruits. 
 The same term is a])plied to an inflorescence yielding the collective 
 fruit of that name (Fig. 587). It is in reality nothing more than a head 
 closely subtended, surrounded or enclosed by an involucre (a). The 
 anthodium is characteristic of the great family Compositae, and is of so 
 much importance in classification that its modifications call for special 
 attention. The involucre should be studied as to whether it is single, 
 double, or multiple — that is, whether it consists of one, two, or more 
 circles of scales; as to whether these are equal in length or whether the 
 outer or inner are successively shorter; whether they are entirely free 
 and distinct, or adnate by their bases or comiate by their margins; as 
 to whether they are appressed, or with more or less of their apical 
 portions recurved or spreading; esi)ecially as to the general ft)rm of 
 the involucre as a whole, the terms used being the same as those i)re- 
 viously applied to the perigone, and as to the characters of the individual 
 scales, these being })ractically the same as those which have already been 
 considered in connection with the leaves. The Ixxiy consisting of the 
 
204 
 
 AN T HOT AX Y 
 
 combined tori of all the flowers of the anthodium, is called a Receptacle 
 (b). It is to be studied as to its being solid or hollow; as to its general 
 form, and especially the form of its upper surface, whether concave, 
 plane, convex, rounded, or conical; as to its being smooth in surface, 
 honeycombed or otherwise, pitted (foveolate), and if the latter, the 
 special characters of the pits and their margins; and as to its being naked 
 or clothed with hairs or scales, and the characters of the latter in their 
 every detail. The head is then to be considered as to the character of 
 its flowers. If these are all sexually similar, the head is said to be 
 Homogamous; if different, Heterogamous. If the flowers are all ligu- 
 late, the head is Liguliflorate. If it possess a disk (e), of tubular flowers 
 (d), it is Discoid. If this disk is surrounded by one or more circles of 
 
 Fig. 587. Vertical section through an anthodium: a, involucre; b, receptacle; c, disk; d, disk- 
 flower; e, ray-flower. 
 
 ligulate flowers called Rays (e), it is Radiate. If the ray-flowers and 
 disk-flowers are of the same color, the head is Homochromous; if 
 different, Heterochromous. The flowers must next be studied as to 
 their sex. The ray-flowers are commonly pistillate, while the disk- 
 flowers are perfect, or the disk-flowers may vary among themselves in 
 this particular. Very commonly, the ray-flowers are entirely neutral. 
 Even if pistillate, they may be sterile. If both classes of flowers are 
 fertile, the akenes which they produce may be heteromorphous, those 
 of the disk being commonly compressed, those of the rays commonly 
 triquetrous. Occasionally the heads are dioecious or monoecious. In 
 one tribe of the Comjjositae the corollas are bilabiate. The character 
 of the pappus (Figs. 74 to 83) is invariably of the utmost importance. 
 
INFLORESCENCE-LEAVES OR FLORAL LEAVES 205 
 
 as are the forms of tlie style-branches and the api)enfhiges l)oriie by 
 these at the apex and by the anthers at apex and at l)ase (see Anth'oe- 
 ciuni and Gynaeciuni). 
 
 Inflorescence-leaves or Floral Leaves.-Many special terms are applied 
 to the forms of inflorescence-leaves, that is, the bracts subtending its 
 branches and the ])edicels of the flowers, as wellas those borne upon 
 the pedicel. Ordinarily they are conspicuously smaller than the other 
 leaves borne by the ])lant. 
 
 With this reduced size, other modifications are noticeable, csj)ccially 
 the shortening or loss of the petiole and a general tendency toward 
 reduction to the scale-form, this tendency counteracted in variable 
 degree by a contrary tendency to preserve the characteristic leaf-form. 
 These leaves are commonly spoken of as the Reduced Leaves of the 
 Inflorescence. To this class belong the leaves of the in\-olucre and the 
 scales often found upon the receptacle of the anthodium already con- 
 sidered. Individually, they are spoken of as bracts, the secondary ones 
 bractlets, and the ultimate very small ones bracteoles. Ordinarily the 
 changes here outlined as marking the development of the foliage-leaves 
 into the inflorescence-leaves are gradual, but in many cases there is an 
 abru])t transition from the one form to the other. 
 
 A circle or cluster of bracts at the base of an inflorescence is termed 
 an Involucre, and this term is also applied to a single very large bract 
 occupying the same position, although this is more commonly known 
 as the Spathe. In most cases the modifications of lca\es forming the 
 scales of involucres are entirely dift'erent from those of bracts occin-ring 
 singly. They are usually much larger than such bracts, their form is 
 usually specialized in some way, and they are very frequently highly 
 colored, serving the same purpose as neutral flowers. The l)racts of 
 involucres are often amalgamated so as to form a cu]) or tube. 
 
 Many one-leaved involucres are very peculiar, and their mori)holog>- 
 even more difficult to understand. The supposed leaf is sometimes a 
 phyllocladium. In some cases the flower appears to rise out of the 
 modified or unmodified leaf itself, as in the Tilid, the explanation in 
 these cases probably being that adiiation exists between tlie inflores- 
 cence and the leaf. 
 
 One group of Families, the grasses and grass-like plants, do not 
 possess any obvious perigone, its place b(>ing snp]ih'ed by peculiarly 
 formed, adapted, and arranged bracts, in tlic form of scales or chafl", 
 and technically called Glumes, which give to this gronj) of families the 
 title Glumaccae. In the rushes, these glumes really are a true 
 perigone, whicli is trinierous. In the sedges (Family Ci/pcrarcoe, 
 
206 
 
 ANTHOTAXY 
 
 Fig. 588) the scales (a) are solitary, subtending each flower. In the 
 grasses (Family Gramincae) the glumes are arranged in pairs, each 
 pair subtending a short branch, which may bear only one, several, or 
 many flowers, the whole known as a Spikelet (Fig. 589). Typically, 
 there is besides the two glumes of the spikelet (a) an additional pair 
 of scales (c) for each flower (6). Thus, if there be but one flower in a 
 spikelet, it possesses two pairs of scales. If more than one, then there is 
 a separate pair of scales for each flower, besides the one pair pertaining 
 to the spikelet as a w^hole. The scales of the spikelet are called the 
 
 Fig. 588. Distichous arrangement of flowers of a sedge, each scale (o) containing a flower {b). .589. 
 Spikelet from the inflorescence of a grass: a, glumes of the spikelet; t, a flower; c, palets of the flower. 
 
 Glumes, Glumes Proper, or Lower Glumes; those of the individual 
 flowers (c) Palets or Upper Glumes. Much complexity in the relations 
 of the glumes ensues as a result of suppression of both glumes or both 
 palets, of one of either or of each, or of two of one and one of the other, 
 and so on. The character of the individual glumes must be carefully 
 studied, as in the case of the involucral scales of the anthodium. The 
 character of the terminal appendages wdiich they bear is of special 
 importance. 
 
 With this study of the inflorescence we are brought again to the 
 individual flower, with the study of which we commenced. 
 
CHA VTKU X \M I I 
 GENERAL CHARACTERS OF CRYPTOGAMS 
 
 Essential Characteristics. — The essential characteristic of tlie flower, 
 distinguishing it from all other similar reproductive structures, is its 
 possession of a special tissue which constitutes a soil in which the 
 microspore germinates, and in which the male gametophyte develops 
 and grows. Plants destitute of such an organ are therefore knowm as 
 Flowerless Plants, An equally great or even greater distinction is 
 found in the fact that the embryo of such plants, resulting from the 
 conjunction of the male and female gametes, is not located in a resting 
 body (the seed), but must continue its uninterrupted development into 
 the sporophyte. They are, therefore, often designated as Seedless Plants. 
 Flowerless or seedless plants are technically known as cryptogams. 
 
 Alternation of Generations. — Our account of the development and 
 reproduction of Phanerogams has shown that each individual passes 
 alternately through two difi'erent forms of life, each of which is repre- 
 sented by its characteristic body form. Those plants which present 
 themselves conspicuously to view as trees, shrubs, and herbs are sporo- 
 phytes, producing spores in ovules and anther cells, these spores ger- 
 minating to produce respectively the male and female gametophytes, 
 which constitute the other form of the plant body, or the alternating 
 generation, and which are too minute to be seen with the naked eye. 
 The sexual elements borne u{)on these gametophytic plants unite to 
 produce an embryo which is the young body of a new sporophytic 
 generation, and which is enclosed in the seed. Such an alternation of 
 generations occurs also among Cryptogams. In some cases the incon- 
 spicuous generation is the gametophyte (Fig. 599), as in Phanerogams; 
 in other cases the relations are reversed in this regard (Fig. 59G). 
 Among many of the lower forms this process does not occur, each ])lant 
 always reproducing to form a body exactly like itself, witii no indica- 
 tion of generations ])resenting distinct forms. 
 
 The Cryptogamous Plant-body. — (ireat as arc the dillerences seen 
 among Phanerogams, e\en greater ones are to be seen among those of 
 Cryptogams. They freciuently present themselves as herbs, shrubs 
 and trees, with wcll-(ieveloj)e(l leaves, borne upon regularly occurring 
 phytomers. In other cases, the stem-structure is well developed, while 
 
208 GENERAL CHARACTERS OF CRYPTOGAMS 
 
 the leaves are rudimentary in ditt'erent degrees, from those which 
 want only the most perfectly develoi)ed leaf-structure to those which 
 are mere scales, consisting of a single layer of flattened cells. By far 
 the greater number, comprising the lower classes, have nothing which 
 can be described as homologous with the leaf, the plant consisting of a 
 simple body which, presenting many different kinds and degrees of 
 variation in form, habit, and function, yet never shows any indication 
 of the regularly jointed structure characteristic of the higher plants, 
 nor any leaves. 
 
 Equally great is the variation observed among the roots. Many of 
 the higher forms possess true absorbing roots, but probably a great 
 majority of roots among Cryptogamous plants are false roots or rhizoids, 
 existing for purposes of fixation only. 
 
 Lacking, as these plants do, the elaborate structures whose character- 
 istics have enabled us to identify, describe, and classify the higher 
 plants, we are obliged to look for such characteristics among the differ- 
 ent arrangements of their cells. Since this work requires the aid of 
 the compound microscope and considerable technical skill, entirely 
 new methods of examination become necessary. We do not, therefore, 
 find it practicable to consider them in detail here. 
 
 The cellular structure of these plants may extend itself in the three 
 directions of solid bodies, giving us masses of tissue, or they may multi- 
 ply in two directions only, giving us flat or superficial bodies, or they 
 may be joined merely end to end, producing filamentous forms. These 
 bodies may each constitute a single plant, or their cells may cohere 
 merely by habit, each living equally well if separately detached ; or they 
 may normally live in a separated condition, thus giving us perfect plant 
 bodies, each consisting of but one cell, the unicellular plant. 
 
 These imicellular plants, furthermore, vary most widely in their 
 own structural characters. They may be of microscopical size, or they 
 may become many feet in length. They may possess the simplest 
 structure, or they may develop large cavities, which are divided and 
 subdivided by processes developed from the wall, and be shaped into 
 remarkable forms, yet without true cell division or multiplication. 
 
 Vegetation. — Regular vegetative processes are of course required 
 wherever growth occurs, wherefore we must look for them among even 
 the simplest forms. In many cases, these processes are as simple as the 
 bodies themselves. Absorption from a surrounding fluid medium by 
 the entire body of the plant, with the simplest of chemical transforma- 
 tions, may exist, or roots or other special organs of absorption, with 
 
REPRODUCTION 209 
 
 coniplicated systems of metaholism and conduction, may l)e developed. 
 Chlorophyll is present in the higher groups, and the vegetative processes 
 are very similar to those which we have before considered. In other 
 classes chlorophyll is wanting, and the plants are hence unable to 
 perform the constructive assimilation which we have found among 
 most Phanerogams, but ready formed compounds, or those readily 
 broken down into the required form, must be found for their support. 
 
 Reproduction. — We find among the reproductive processes in Crypto- 
 gams almost as great a diversity as among their other characters. Not 
 only do both vegetative and sexual forms exist, as among Phanerogams, 
 but while many groups exhibit both forms, others possess only the 
 vegetative. Among the higher classes, the vegetative forms of repro- 
 duction are quite elaborate, involving phytomer-like parts, either singly 
 or in bud-forms, while in other cases it can occur by single leaves or 
 parts of them. Among the lower classes, where phytomers and leaves 
 are unknown, these processes are necessarily simpler. In their higher 
 members, masses of tissue, often specially constructed, called gemmae or 
 buds (but of course not conspicuously homologous with the buds which 
 we have studied), separate to form new plant-bodies, the process being 
 called gemmation. In other cases the process is the simplest possible 
 one of cell-division. 
 
 Sexual reproduction among cryptogams is too variable to be here 
 considered, even in a general way. In no Cryptogamous plant, how- 
 ever, is there developed any structure which combines the varied 
 functions of that which among Phanerogams is called the flower. The 
 extension of this term to any reproductive organ of the former group, 
 merely because certain homologies have been discovered between 
 them and the flower, is misleading, as it tends to magnify slight resem- 
 blances into a higher degree of importance than great differences, and 
 it furthermore subverts the original and fully established meaning of a 
 common term into a new, even if it were a strictly accurate, application. 
 
 When alternation of generations occurs, with the production of 
 distinct gametophytes, the male cells, in the form of antherozoids, are 
 usually i)rovided with some independent power of locomotion for 
 reaching the female element, known as the Central ( 'ell, within a tlistinct 
 organ called by various names. 
 
 It has already been stated that the spores germinate for the ])r()duction 
 of these gametoi)hytes in any suitable soil, and that the resulting 
 embryo continues its development without passing into a resting or 
 seed stage. 
 14 
 
210 GENERAL CHARACTERS OF CRYPTOGAMS 
 
 PRINCIPAL GROUPS OF CRYPTOGAMS 
 
 The main groiii)s of the cryptogams are indicated in the following 
 table: 
 
 1. Thallophyta or Thallophytes. 
 
 (a) Fungi. 
 (6) Algae, 
 (c) Lichenes or Lichens. 
 
 2. Bryophyta or Bryophytes. 
 
 (a) Hepaticae or Liverworts. 
 (6) Musci or Mosses. 
 
 3. Pteridophyta or Pteridophytes. 
 
 (a) Eqiiisetaceae or Horse-tails. 
 ih) Lycopodiaceae or Club-mosses, 
 (c) Filices or Ferns. 
 
 Each of these groups will be briefly considered, in so far as relates 
 to its contributions to the materia medica. 
 
 Thallophyta.— r/^e Fungi. — The Fungi comprise plants destitute of 
 true chlorophyll, and therefore incapable of building up their own 
 food from elementary substances. Their structural and physiological 
 characters are exceedingly varied. 
 
 To the Fungi belong the Bacteria, contributing the great majority 
 of disease germs, in the special uses of which we are yet to find the 
 most important part of our materia medica. The study of this group 
 pertains to the subject of Bacteriology. 
 
 To the F'ungi belong also the yeast plants, valuable medicinal agents, 
 but unicellular, and to be studied only in the microscopical laboratory. 
 
 Among the drugs of interest to commercial pharmacognosy, occur 
 only Kefir grains, Taka-diastase, Ergot, and the Agarics, all of which 
 belong in the higher divisions of the group. 
 
 The vegetative portion of the Fungi consists of a tissue called 
 Micelium, formed of filaments, often growing into large and dense 
 masses. In many, this micelium, after forming into a hard mass, 
 becomes dormant, and constitutes a resting body called the Sclerotium 
 {e. g., Ergot), which later, under suitable conditions, gives origin to the 
 spore-bearing body. Some of the Fungi have no higher mode of repro- 
 duction than that of simple division (fission), although almost all of 
 them reproduce by means of spores. These spores are borne in various 
 
rilALLOPIIYTA 
 
 211 
 
 ways (Fig. 591), as to both their minute and conspicuous structures. 
 In the higher forms, such as tlie mushrooms, tliis ])ocly consists of a stem 
 bearing a cap or Pileus (Fig. 590, a), wliich bears tlie si)ores under- 
 neath, on gills, teeth, or some 
 simihir support (Fig. 591). 
 
 The Algae.— The Algae 
 are almost without rei)re- 
 sentation in the materia 
 medica, although they yield 
 important food supplies, 
 especially in Japan. P^ven 
 Chondrus, the most impor- 
 tant member in drug com- 
 merce, is in reality only a 
 food, while Fucus acts ratlicr 
 by inorganics, absorl)ed by 
 it from the sea-water, than 
 by any organic princi])lc of 
 its own. 
 
 Fig. 590. Amanita phalloides. 
 
 Fig. 591. Showing parts of Mushroom— .4oaric«s 
 {FsalUola) campestris: A, a section across a number of 
 gills, h; the hymenophore, /; the lamellae or gills, one of 
 which is more highly magnified in B, t, the central hyphal 
 tissue; liy, the /li/mivuiaH, or spore-bearing surface; C,a 
 portion of gill still more highly magnified, // the hyphae, 
 q; the basidia upon which the conidia or spores are borne, 
 s, s', »■" — conidia in different stages. (Sachs.) 
 
 The Algae are essentially atiualics, and diU'cr from the Fungi in 
 possessing chloro})hyll or some similar substance, by which they are 
 enabled to l)uil(l up their food sui)i)lics from inorganic matter. 
 
 The last nicnti()iu>d plant is among the liighcst of this class. The 
 thallus, or ])lant body (Fig. 592), coiisi.Ntiiig of a loose aggregation of 
 single cells, has a well-developed foot, tl.e di-k. by which it clings to 
 
212 
 
 GENERAL CHARACTERS OF CRYPTOGAMS 
 
 rocks. The stem is branching and bears the reproductive bodies (Fig. 
 593) at the ends of its branches. 
 
 Fig. 592. Rock Weed, Fucus: A, portion of branch bearing reproductive organs, /; B, an enlarged 
 section through a reproductive organ, the female conceptacle, showing egg cells, c; the cavity, b; 
 false parenchymatic tissue, d. (After Thuret.) 
 
 LAJ 
 
 ^^^#^'- 
 
 Fig. 593 The sexual organs of Fucus 4, the antheridia, or male organs, a, borne on paraphyses; 
 B, antherozoids or gametes, /, the oogonium or female organ, og; paraphyses, p; II, the oospores 
 (oospheres), preparing to be set free; ///, a free oospore, being fertilized; IV, V, young Fucus plants. 
 
THE BRYOl'IlYTA 
 
 213 
 
 DillVroiit sexes are hoi'iu' on dillci-ciit ])laiits. The t'einale uv\:;\\\ 
 consists of a number of sini])Ie ovaries ((Jogonia) (Fig. 592, c; Fig, 593, 
 ocj), grouped together in a Conceptacle. Eacli oogonium contains eight 
 Odsplieres. These oospheres are set free and are fertiHzed by motile 
 Gametes, tlie Antherozoids, which are produced in conceptacles of 
 another plant. 
 
 The Lichens. — Most systematists now regard the Lichens as belonging 
 to the Fungi. They may be defined as Fungi parasitic on certain 
 Algae. In this form of parasitism each plant supplies some indispen- 
 sable contribution to the other, the relation being therefore called wSym- 
 l)iosis. ^riie body of the Lichen, more particularly in the larger forms, 
 is made uj) of the Fungus mycelium (Fig. 595, sh). The thallus may 
 
 Fid. 594. Concral viow of several Lichens: A, crustaceous (Graphis); B, a portion of this samelichen 
 more highly magnifiod, showing apothecia; C, a crustaceous lichen, Pcrtusaria; D, a sub-foliaceous 
 thallus of Parmdia with numerous spore-bearing bodies, apothecia. (Sachs.) 
 
 be large and flat, leathery and leaf-like (foliaceous. Fig. 594, D), or 
 upright and branching (fruticose), or close-clinging to the bark of 
 trees, looking like a colored stain on rocks (crustaceous, Fig. 594,^1, O- 
 Li most cases the spores are born, eight together, in little sacs called 
 Asci, which are themselves reproduced in variously colored dosed or 
 open A])()th('cia (Fig. 594, D). 
 
 The Bryophyta. — Li this class the cons])icuous generation is the 
 gametophyte which, in the higher divisions (left hand. Fig. 59(5), 
 becomes a well-developed plant with stem and leaves. Its male repro- 
 ductive organs are the Antheridia (Fig. 597, a); its female are the 
 Archegonia. The efl'ect of reproduction is the j^roduction of an embryo, 
 which immediately germinates while upon the gametophyte, sending 
 its foot down into the tissue of the latter, and developing upward into 
 
214 
 
 GENERAL CHARACTERS OF CRYPTOGAMS 
 
 a sporophyte (Fio:. 596, .9, /, c), wliicli is tlie Capsule. These ripened 
 spores, in turn, germinate to produce a new gamet()i)hyte which, in its 
 embryonic state, is called the Protonema. It will be observed that the 
 
 A 
 
 fA\ 
 
 Fig. 595. An Ascomycetous Fungus — Peziza — 
 A, showing section through complete spore- 
 bearing body — the apothecium; h, tlie hyme- 
 nium: s, the hyphae, forming false tissue; B, 
 enlarged section of a portion of above showing 
 a, b, c, d, e,f, asci, in various sizes and in various 
 stages of spore development taking place within 
 them, spores are mature in /, sh, the false paren- 
 chyma made up of intertwining hyphae. 
 
 Fig. 596. Showing the development of sporo- 
 phyte of moss: St, apex of stem, bearing the 
 female organs; o, the archegonia; from these, 
 after fertilization, the young capsules spring, 
 C, S, V; C, the calyptra; underneath which is 
 found lid or operculum; /, the capsule; s, the 
 leafless stem of sporophyte or pedicel. (Frank.) 
 
 relative positions of sporophyte and gametophyte are exactly the 
 reverse of what they are in the flowering plant. 
 
 Although the hair-cap moss is somewhat used in medicine, yet 
 
THE PrERIDOPIIYTA 
 
 215 
 
 iieitlier tlie TTepatics nor Mosses may be considered as worthy of note in 
 commercial pharmacognosy. In the Mosses, the top of tlie stem or 
 branch bears a number of bracts or modified leaves, which constitute 
 the Perichaetium. From amidst these bracts the Pedicel (Fig. 59G, s) 
 rises from the foot and bears the capsule upon its summit. Through 
 
 i^*^^,. 
 
 Sli' / .1 
 
 ^l 
 
 Fig. 507 The male organ, antheridium of 
 mosses (Funaria): A, antheridium, with escaping 
 antherozoids (o) ; B, a single male element 6, in 
 mother cell; C, free, with two cilia. 
 
 Fig. 598. Lycopodium: S. the oone-like spore- 
 Wearing leaves; B, an enlarged sporophyll leaf; 
 h, the blade, and sp, the sporangium which con- 
 tains the spores. 
 
 the center of the ca])sule the Pedicel is continued as the Columella, and 
 at its summit it is closed in until mature by one or more coverings. By 
 a special organ, the Peristome, consisting of a number of teeth, it is 
 l)ossible for the capsule to be closed during wet weather and opened 
 for the (listrihiitioii of its spores when it is dry. 
 
 The Pteridophyta. — All three groups of this division contribute more 
 or less important articles to the commercial materia mcdica. 
 
 Equisetaceae. — In this group again we ha\e, as in {\\v flowering 
 plant, a gametophyte which is microscopic, although, unlike that of 
 the flowering plants, it is produced entirely disconnected from the 
 sporophyte. From it develop hollow-stennned i)lants which are com- 
 monly known as horse-tails or scouring rushes. The latter name is in 
 allusion to the large amount of silica produced in their superficial 
 
216 GENERAL CHARACTERS OF CRYPTOGAMS 
 
 tissues, on account of which they are frequently used for scouring 
 purposes. Medicinally they ha^•e' practically no use, although it is 
 said that poisonous properties exist in one or more of them. 
 
 Lycopodlaceae. — The club mosses, like the horse-tails, are said to 
 contain some poisonous species, but their interest in drug commerce 
 resides wholly in the use of the spores of some species, inider the name of 
 Lycopodium or vegetable sulphur. In the species yielding this product 
 there are two forms of leaves, those upon the fruiting portion differing 
 materially from those of the main stem (Pig. 598). In this group the 
 spores are all similar (Homosporous), while in some of the lower groups 
 they are of two forms (Heterosporous). As in the class last considered, 
 the gametophyte is microscopic, while the sporophyte is the con- 
 spicuous generation. Upon the upper surfaces, or in the axils, of the 
 leaves of the fruiting branch the spore-cases (Fig. 598, sp) are solitary. 
 In collecting Lycopodium, it is customary to pull off these tops and 
 allow them to dry thoroughly, whereupon the spores are easily shaken 
 out. 
 
 TJw Filices. — The ferns contribute a number of important articles 
 to the materia medica, the principal of which is Aspidium, or Male 
 Fern. 
 
 From a pharmacognostical viewpoint, the chief difference between the 
 ferns and the flowering plants is in the stem-structure. The main stem 
 is usually under ground, although often aerial and sometimes assuming 
 the dimensions of a shrub or tree. In the Hawaiian Islands these 
 trunks furnish timber for "large amd heavy planking. The peculiarity 
 of the fern-stem is its possession of a number of steles, each having 
 its own endodermis. As compared with the stem of an ordinary dicotyl- 
 edon, that of the fern presents the structural appearance of being a 
 fascicle of stems, bound together by an interstellar tissue. This indica- 
 tion is borne out by the peculiarities of the structures which fill the 
 office of the leaves of other plants, and which are known as Fronds. 
 While thus taking the place of ordinary leaves and appearing to be 
 such, these are seen, on closer examination, to be the homologues not 
 of leaves, but of stems, each of them originating from and representing 
 one of the steles of the compound stem. There is, moreover, no such 
 division of the stem into phytomers as we see in the flowering plants. 
 
 It is not necessary to study the main stem in order to discover the 
 wide difference between the leaf and the fern frond, for if one but 
 watches the development and behavior of fronds, especially in certain 
 groups, as the Gleichenias, he will be struck by the fact that it is, in its 
 
THE I' TEHl DO I' II Y TA 
 
 217 
 
 real iiaturi'. more like a \ivvvu and (lattoiicd stem than a leaf. These 
 facts have led many inorplioloyists to look upon the fern-frond as a 
 structure distinct in kind from the leaf. 
 
 In the ferns we again find the gamet()i)hyte small and inconspicu- 
 ous (Fig. 599), while the sporophyte is the generaffon familiarly known 
 to us. These sporoj)hytes may he herhs, shrubs, or trees, and many of 
 them are climbers. 
 
 Fig. 599. Organs of reproduction in the ferns: J, //, III (p), prothallium or gamctophyte; a, the 
 male organ, antheridium in various stages of growth of antherozoids, which in h are sliown free and 
 provided with cilia; c, oo.spore or egg cell: E, the archegonium — developing into young fern plant — h. 
 
 The sporangia may be borne on tlie lower surface of the one form of 
 frond possessed by a species, or the sporophyll may be entirely different 
 from the other fronds. In the former case, the sporangia are grouped 
 in little masses, forming rusty- or dark-colored spots on the surface 
 which are known as Sori or Fruit-dots. These may be naked, or partly 
 or wholly covered by the reflex and modified margin of the frond, or by 
 special bract-like membranes, developed from the surface of the frond. 
 Such a membrane is called an Indusium. When the sporophyll is of 
 special form, the modes of arranging, enclosing, or protecting the 
 sporangia are various. I'pon these characters, and upon those of the 
 sporangia themselves, is chiefly based the classification of the ferns. 
 
"CHAPTER XIX 
 
 'BOTANICAL CLASSIFICATION AND ANALYSIS 
 
 Reference was made in our introductory chapter to the object of 
 Systematic Botany as being the arrangement of plants in a system or 
 series which should indicate approximately the successive order of 
 their appearance in existence, that is, of their development, or of their 
 creation, as commonly expressed. The Cryptogams or flowerless 
 plants undoubtedly existed first, and from some one or more of their 
 sub-divisions the flowering plants developed. The former are therefore 
 regarded as "lower" than the latter, and are treated as the basal or 
 fundamental division of plants. Similarly, certain of their divisions 
 occupy the relation of having existed before others and of having given 
 origin to them, and are therefore regarded as occupying the lower 
 positions in the cryptogamic series. By determining those relations 
 for the various sub-divisions, we obtain grounds for arranging all the 
 cryptogams in a sequence of which it may be said, in general, that the 
 lower came first to exist and the latter are newer in creation. By apply- 
 ing the same methods, the Phanerogams are formed into a similar 
 series. 
 
 It must not be understood that these groups occupy an unbroken 
 serial relation to one another, like the rounds of a ladder. They would 
 do so had each group given origin to only one other, and had all the 
 groups maintained their existence, or even left evidences of having 
 existed, so that their relative positions could be assigned them. Instead 
 of this, a formerly existing group frequently, probably usually, gave 
 origin to several new forms, many of which became the starting points 
 for others, so that the system is more like that of the branching of a 
 tree than of a series of steps. Furthermore, it has frequently happened 
 that a recent form has continued in existence, while that from which 
 it originated has perished and left no record. So great an influence 
 have those conditions exerted that we have various groups now in exist- 
 ence, which show no special relationship to any other, and we have to 
 assign them somewhat arbitrarily to their positions. For thejiliind 
 similar reasons, our system is at the best faulty and incomplete, and tlilfr 
 
SPECIES 219 
 
 nature of tlio case is such tliat it i)r()l)al)ly must always remain so. In 
 spite, however, of all these imjierfections, steady and great progress has 
 been and is being made, and this natural system of classification must 
 be regarded as a most useful attemi)t to indicate just such genetic 
 relationships as exist among human beings. 
 
 The divisions and sub-divisions thus established stand as ft>llows: 
 
 Divisions. — Of which there are two, the Cryptogamia and Phanero- 
 gamia, the latter being now often called Spermatophyta, as the pro- 
 duction of seeds is regarded as their most important characteristic. 
 
 Sub-divisions. — Leaving out of consideration the divisions of the 
 Cryptogamia, we find the Phanerogamia divided with two sub-divisions, 
 the Gymnospcrmae and the Angiosperniae, the latter the higher. 
 
 Classes. — Leaving out of account the Gymnospermae, the Angio- 
 spermae are divided into two classes, the Monocotyledons and the 
 Dicotyledons. 
 
 Series. — The Dicotyledons are divided into three series, the Thal- 
 amiflorae, Disciflorae and Calycifiorae. 
 
 Cohorts. — Each of the series named above is divided into a num])er of 
 Cohorts, or orders. Thus the Thalamiflorae have G cohorts, namely, 
 Ranales, Parietalcs, Polygalinae, CaryophylUneae, Guttifcrales, and 
 Mai vales. 
 
 Families. — Each cohort consists of a number of Fatnilics, of which 
 there are about 3{)() among flowering plants, the Ranunculaceae or 
 Buttercup Eamily and the Compositae or Daisy Eamily being exam})les. 
 
 Sub-families and Tribes. — Families, if large or heterogeneous, are 
 often divided into Tribes, or into Sub-families, the latter then divided 
 into Tribes. Thus, the Ranunculaceae contain 5, the Compositae 13 
 tribes. 
 
 Genera. — Families, either directly or through their tribes, are divided 
 into genera, of which the most modern authorities recognize between 
 8()()() and 9(K)() in all the families of flowering ])lants. The genera are 
 very irregularly distributed among the families. Thus, the family 
 Columelliaceae contains but one genus, Coluinellia,\\hi\e the CoDiposiiae 
 is made up of some SOO of them. 
 
 Species. — Genera, either directly or through a number of Sub-genera, 
 are made u]) of species, of which there are })robal)ly not far from 2r)(),()()() 
 now described among flowering plants. These are very irregularly 
 distributed among the genera, many of the latter containing but one 
 species, while others contain hundreds. Solanuui. pi-obablx' tlic largest 
 genus, has been credited with as many as 1200 species. 
 
220 BOTANICAL CLASSIFICATION AND ANALYSIS 
 
 A species is considered as an nitimate individual kind of plant, like 
 the Red Maple, the ordinary medicinal Wild Cherry, or the Two-leaved 
 Pink Ladyslipper. 
 
 Varieties. — Varieties frequently exist among the individuals of a 
 species. It is practically impossible to establish rules for determining 
 whether two closely related forms are two species or two varieties of 
 one species, and there is hardly a point upon which our botanists are 
 more at a disagreement than in estimating these cases. It may be said 
 that a variety is a form of a species which depends either upon a natural 
 tendency to vary, or upon modifications brought about by difl'erent 
 climatic conditions or other environment, but which, in either case, is 
 not permanently fixed, its descendants being liable under various con- 
 ditions to reassume the characters of the parent. The characters of a 
 species are, upon the other hand, supposed to have become permanently 
 fixed. It may, of course, vary, but there is no special tendency for it 
 to vary in the direction of the ancestral form more than from it, in a 
 new direction. 
 
 Forms. — Variations which are not at all fixed, and clearly temporary 
 in their nature, as the occurrence of a white fiower among plants habitu- 
 ally blue-flowered, give rise to Forms. These are hardly considered 
 worthy of names. 
 
 Botanical Analysis. — This consists in the determination of the botani- 
 cal ])osition and name, if it have one, of a plant, by comparing it with 
 published descriptions until that one is found with which it agrees. 
 To make such comparisons individually, and without system, would 
 prove interminable among such a vast number of species, and the system 
 of classification above mentioned is employed to reduce to a minimum 
 the time and labor required. The process is essentially one of successive 
 exclusions of the plant under study from more or less extensive divisions 
 and subdivisions. 
 
 By determining that our plant produces flowers and seeds, we exclude 
 it from the Cryptogamia, approximately half of the vegetable kingdom. 
 Another similar act excludes either the Angiospermae or Gymnospermae 
 and another, if it be an Angiosperm, from either the Monocotyledones 
 or Dicotyledones. As the process continues, it becomes somewhat more 
 complicated. The first steps may be positively taken by deciding a 
 single point, but farther on, in determining the family, genus, and 
 species, groups of characters have to be considered together, and 
 held in mind at the same time for comparison. This is in general due 
 to the fact that the characters separating the primary groups are 
 
BOTANICAL ANALYSIS 221 
 
 older in time, and tlierei'ore more constant and less inclined to vary, 
 while those characterizinjj the lesser groups are more recent in their 
 origin, and nnicli inclined to vary in diflerent individuals. They are, 
 therefore, less trustworthy and have to be considered in connection 
 with others. It is for this reason that the most frequented ifl'erences of 
 opinion concerning classification among botanists relate to genera, 
 species and varieties. 
 
CHAPTER XX 
 
 BOTANICAL NOMENCLATURE 
 
 In naming a plant, the object is to apply a name which does not and 
 cannot be made to apply to any other. A familiar illustration is the 
 name of the common Red Maple. In scientific circles the name " Red 
 jNIaple" cannot be regarded as sufficiently exact and definite, because 
 in different localities it is known as Soft maple, Swamp maple, White 
 maple, and Early maple; while doubtless different maples are called 
 "Red" in different localities. 
 
 Scientific accuracy, therefore, renders it indispensable that a system 
 of botanical or scientific names, as distinguishable from the common, 
 vulgar, or trivial names, shall be employed. The name Acer is, therefore, 
 applied to the genus to which the maples belong, and this is known 
 as the generic name of all the species of j\Iaple. One of the rules of 
 nomenclature requires that no other genus shall bear this name. In 
 order to distinguish the different species of Acer, each must have, 
 in addition, its specific name, the Red jNIaple receiving the specific 
 name of Rubruni. It is, therefore, to be known as the Rubruvi AeeVj 
 although the Latin form, with the generic name preceding, is employed 
 thus, Acer ruhrum, the specific name, except in certain cases, beginning 
 with a small letter. By another rule of nomenclature, only this par- 
 ticular Acer may be called ruhrum, although this name may be applied to 
 plants in other genera than Acer. It is clear now that this combination 
 of generic and specific names yields a complete name, and this is called 
 the Binomial, which may not be applied to any other plant in the world, 
 while either its generic or specific name may be. 
 
 It often happens that a plant name is for one reason or another 
 abandoned by some, or most, or even all botanists. It is not then 
 permitted that it be given to another plant, because it is liable at any 
 time to be used again in its old application by other botanists, so that 
 we should then come to have two plants of that name. 
 
 In spite of the rules here stated, it frequently does happen, very 
 frequently has happened in the past, that a botanist, ignorant or care- 
 less that a certain name has been used, applies it to some other species, 
 
BOTANICAL NOMENCLATURE 223 
 
 thus causing a duplication. In such a case the name Acer rnbrum 
 could not inform us with certainty which species was referred to by the 
 writer or s])eaker. It might, for example, he an Am- niJn-inn made by 
 Linne in 1753 or one so named by some one else in ISSO. It is therefore 
 necessary to add to the plant-name the name of its jnitlior, thus, .leer 
 rubrum Linne. This necessity for the use of the a.uthor's name is semi- 
 barbarous, and is a mere monument to the lack of system in plant- 
 naming which once existed. With the perfect systematizing of nomen- 
 clature this necessity will pass away. For convenience, it is customary 
 to abbreviate the name of the author thus, L. for Linne, Reichb. for 
 Reichenbach, or Benth. for Bentham. The generic name may also 
 be abbreviated in many cases by writing only its first letter, followed 
 by a period, thus, A. rubrum L. This of course can only be done when 
 it is well understood to what genus the writer is referring. For example, 
 in the above cases, where we have been speaking only of Acers, the 
 abbreviation "A." can be employed with entire satisfaction. 
 
 A name in parentliesis will sometimes be found interposed between 
 the generic and specific names thus, Acer (Negundo) aceroidcs. This 
 indicates that the genus consists of two or more sub-genera, the one in 
 this case being Negundo. It is not customary to indicate the sub- 
 genus in this way, but a writer often desires for some special reason to 
 do so. 
 
 The name of an author enclosed in parenthesis is often seen standing 
 between the specific name and that of the author, thus Acer aceroides 
 (^Nloench) Gray. This means that the botanist named in the paren- 
 thesis assigned to the plant its specific name, but connected it with 
 some other genus, the later author, whose name follows the parenthesis, 
 having transferred it to the present genus, thus creating the present 
 binominal. In all cases where a plant is thus transferred to a different 
 genus, it must retain its original specific name, unless the genus to which 
 it is so transferred already has a species with that name, in which case 
 a new specific name must be assigned, this necessity being to a^•oid 
 binomial duplication. 
 
 Wlicn the name of the author in parenthesis is not followed by 
 another, it means that the writer claims that this binomial has never 
 been printed and that he must henceforward be cited as its author. 
 
 We frequently see a trinomial used as the name of a jilant. thus, 
 Viola tricolor alba, no parenthesis being used for the middle iianic. 
 This indicates that the species Jlola tricolor sometimes exhii)its a form 
 possessing white flowers, and that this form is regarded as a variety of 
 
224 BOTANICAL NOMENCLATURE 
 
 the species. The name alha is in this case called the varietal name. 
 Another way of writing it, but which has not the sanction of botanists, 
 is "Viola tricolor, var. alba." 
 
 The use of capitals and italics in printing botanical names is not, 
 except in special cases, of botanical significance or authority, though 
 attempts have been made to so treat it. Literature and individual 
 taste supply the rules for this usage. This statement does not, how- 
 ever, apply in the case of the initial of the generic name or of the name 
 of the author. 
 
 It has been shown above how two plants may come to have the same 
 name assigned to them. In even a greater number of instances have 
 several different names come to be applied to the same plant. The 
 extent to which this has occurred may be realized from the fact that 
 more than eight hundred thousand names exist for the two hundred 
 and fifty thousand known flowering plants, this being an average of 
 more than three names for each plant. Since only one name can be 
 recognized for a plant and only one plant for a name, it follows that 
 all others must be regarded as synonyms and should not be used. 
 Until a comparatively recent period very autocratic methods have 
 ruled in the selection and application of names under these circum- 
 stances. Each country has had but a few, or even but one botanist 
 who assumed authority, and these have, in most instances, acted 
 irregularly and inconsistently in selecting and applying their names. 
 Now, however, most botanists recognize the importance of having some 
 uniform custom, based upon sound principles, and the attempts in this 
 direction ^re likely to result in great improvement. 
 
 The fuxidamental rule of nomenclature is that the first names, generic, 
 specific, and binomial, ever given to a plant, beginning with the year 
 1753, sh?ll be permanent, provided that they do not involve errors. 
 Such errors may be literary or botanical. Literary errors may consist 
 in wrong spelling or inflection, or in a composite derivation, part of 
 the name being taken from the Greek and part from the Latin. Such 
 errors do not justify the substitution of another name, but only a correc- 
 tion, with as little change as possible. Botanical errors justifying the 
 substitution of a new name are numerous and varied. The most 
 common is the reference of the plant to a wrong genus, as calling a 
 Ruhus a Rosa. Whoever discovers such a mistake is required to refer 
 the species to its proper genus, but its specific name must if possible 
 remain unchanged. The name of the author of the specific name then 
 goes in parenthesis, as already explained. Not ah changes of this sort 
 
BO TA NIC A L NOMENCLA TURK 225 
 
 indicate actual errors. The lines of distinction Ix'twccn two f,fcncra 
 are often very ari)itrary, the different ()i)inions of different botanists 
 being apparently equally well founded. One botanist will thus regard 
 as of one genus plants which another divides among two or more genera. 
 
 Another very common error in the past was that of assigning to a 
 genus a name which had already been applied to another. This, of 
 course, necessitates a re-naming of the genus, all the specific names 
 remaining unchanged and their autliors cited in ])arenthesis as already 
 explained. 
 
 Errors in specific names have occurred most frequently through the 
 re-naming of a species which has already been published under a difierent 
 name. In such cases, when the error is discovered, the name last given 
 must fall. A difference of opinion has existed as to whether such a 
 discarded name should be permitted to be afterward taken up and 
 applied to a newly discovered plant. If the error in the first use of the 
 name were beyond question, no harm would result from so doing, but 
 such is not the case. In numerous cases botanists have disagreed as 
 to the specific identity of two plants. One regards one of the plants 
 as a mere accidental or temporary state of the other and discards its 
 specific name. If, now, the discarded name be applied to some other 
 species of that genus, there is danger that at any time the original 
 opinion may be revived concerning the previous application of that 
 name. This having in the meantime been applied to another si)ecies, 
 we have the same name applied to two species. For this reason conser- 
 vative botanists hold that just as a generic name once discarded may 
 never be given to another genus, so a specific name, once dropped, 
 may never be applied to any other species in the same genus. ' This 
 constitutes the important rule often referred to, as in the cxjjression, 
 "Once a synonym (or homonym) always a synonym." 
 
 The whole subject of nomenclature and the rules which have been 
 formulated for it are very extended and c()mi)licated, but the most 
 important ])rinciples upon wliicli the rules are based have here been 
 explained. 
 
 15 
 
CHAPTER XXI 
 
 THE COLLECTION AND PRESERVATION OF BOTANICAL SPECIMENS 
 
 The study of botany cannot be properly pursued without the pres- 
 ervation of specimens. The mistake is very general of assuming that 
 such material is required only in case of the making of a permanent 
 herbarium. It is necessary besides as a temporary expedient in the 
 thorough study of plants. A plant is not studied until all its parts 
 have been examined. As the mature fruit is rarely present with the 
 flower, and as the stem, leaves and underground portions are liable to 
 present different characters at different seasons, it becomes necessary 
 to make several collections from the same plant and to preserve them 
 to be studied together. There is, moreover, a waste of time involved 
 in using the summer season for dissection and study, when the attention 
 should be directed to field-work. 
 
 Specimens may be preserved in alcohol or in formaldehyde or other 
 solution, or they may be preserved by drying. The latter method is 
 usually employed and is the more generally useful, although it possesses 
 certain disadvantages which will be referred to further on. 
 
 Alcoholic specimens are made by simply immersing the material In 
 alcohol and sealing perfecth'. Very fleshy specimens may require a 
 change of alcohol after a time. An improvement on this method is to 
 immerse them in 50 per cent, alcohol for a few days, then transfer them 
 to 75 per cent, alcohol and later to that of full strength (95 per cent.). 
 Alcohol is liable to remove coloring matters and many other substances, 
 as well as to extract the natural water, thus giving to the specimens a 
 shriveled or wrinkled appearance. The use of a formaldehyde solution 
 obviates both of these difficulties, even the most delicate colors being 
 in most cases perfectly preserved. The strength of the solution ranges 
 from 3 to 9 per cent., ordinary water being employed as a vehicle. In 
 the case of fleshy fruits and some other substances, it is found necessary 
 to pour off the first solution and apply a fresh one after a few days, and 
 this renewal may be called for from time to time as the specimens show 
 signs of deterioration. Under the very best of conditions, it must be 
 expected that some changes will occur in the appearance of specimens 
 preserved in solution, and the same is true of those prepared by drying, 
 
THE RECORD HOOK Til 
 
 SO that it hfcomcs necessary to take careful notes re<^ar(]in<;- ])lants at 
 the time of their collection. 
 
 The Record Book.— The record is to include the colle<tion number of 
 the specimen, which is also to })e attached to the specimen at the same 
 time, the date, locality, altitude, habitat, habit of the ])lant, color and 
 any other facts not likely to be readily reco<i;ni/e(l in the dried specimen. 
 
 FieU No. 
 256 
 
 O 
 
 Bolivian Flora. 
 
 
 ! « 
 
 : & 
 
 : *i 
 
 
 1 1 
 
 
 Bang Collection. 
 
 Field No. 
 
 i 
 
 
 
 1 j 
 
 Ci 
 
 250 
 
 G 
 
 
 
 
 i 
 
 
 Bolirian Flora. 
 
 
 
 
 H-" J 
 
 
 Bang Collection. 
 
 
 ! I 
 
 
 O : 
 : 
 
 
 Field No. 
 
 260 
 
 o 1" 
 
 
 
 i 
 
 
 o 
 
 Bolivian Flora. 
 
 5' Q 
 
 
 ^ 
 
 
 
 Bang Collection. 
 
 _= ■ 
 
 
 a 
 
 
 
 The l)est form of note-book is one containing lOO pages like that here 
 figured, a convenient size for which is 4 x 7 inches and printed on \ery 
 strong and tough paper, such as cartridge-pai)er. The numbers borne 
 on these pages are to be printed by machine, so as to avoid all pos- 
 sible form of error. Through the holes in the tags at the bottom of the 
 page strings are to be tied and the tags are to be firmly attached to the 
 specimens. When the specimen is studied later there can thus be no 
 possible question as to the specimen to which the notes refer. When 
 the specimen is finally mounted in the herbarium, the remainder of the 
 page should be torn out and glued to the sheet, the tag still remaining 
 attached to the plant as indisi)utable evidence of identity. With 
 great care, a similar assurance is i)ossible without these elaborate 
 provisions. 
 
 Besides the notes referred to aboxe, it may Ix- necessary to note the 
 dioecious character of a plant, in which case that of the other sex must 
 also be sought. This should be given the same number, followed by 
 the proper sexual sign or by the letter a or b. If the leaves are not yet 
 developed when the flowers appear, as is frecjueutly the case with early 
 
228 THE COLLECTION OF BOTANICAL SPECIMENS 
 
 spring flowers, an estimate should be made of the time when the leaves 
 will probably be ready for collection and the number of the plant 
 entered in an engagement calendar under the pro])er date at which the 
 place should be again visited. The same thing is true in case the fruit 
 is not ready at the time of .the collection of the flowers. In these cases 
 it is best to attach a tag to the living plant at the time of the first 
 collection to avoid all possibility of confusing two species in the final 
 complete collections. 
 
 Selecting the Specimens. — This matter of representing all parts of the 
 plant and the same parts at different seasons is of special importance 
 in case of pharmaceutical studies. Even the winter-buds and the 
 underground portions in the winter season should be secured. One of the 
 most important points is to secure the root-leaves of ordinary herbaceous 
 plants, as well as the peculiar leaves of trees and shrubs which often 
 grow upon root-suckers or upon young specimens. It is also wise to 
 cause the germination of seeds and to preserve the seedlings with the 
 remainder of the specimen. Pharmaceutical specimens moreover should 
 represent the bark and the wood and these may with profit be taken 
 separately from root, stem and branch. 
 
 Ordinary herbarium specimens, when finally completed, skould 
 not exceed sixteen inches in extreme length by ten inches in width. 
 Even specimens of three or four feet in length may be easily reduced 
 to this size by kinking and folding them at the proper points without 
 entirely separating any part. Underground port ons, when not too 
 large, should remain attached. Inconveniently thick portions, such 
 as tubers or fruits, may be split and one or both parts preser^'ed, or the 
 centre may be cut out so as to reduce the thickness. In the case of 
 large specimens, it will frequently be found necessary to remove a 
 portion of the leaves. This should be very judiciously done, those 
 retained being left at difi'erent points upon the specimen so as to show 
 the successive modifications, and portions of the petioles should be 
 left so as to indicate their position. In case of large plants, such as 
 shrubs and trees, where only a branch can be preserved, it is impor- 
 tant to select this branch from a part where growth has been free 
 and unrestricted and a natural symmetry attained. With each 
 specimen, a few loose flowers and buds should be preserved for 
 dissection i)urposes. 
 
 Preserving the Specimen. — Specimens thus taken should be at once 
 transferred to a portfolio carried into the field. Various forms of 
 portfolios are for sale by botanical supply houses. They may be 
 
PRESERVING THE SPECIMENS 229 
 
 made of cardboai'd, wood-ljoard, wooden lattiee work or wire frames, and 
 they should be earried iu a strong- ])air of strai)s, simihir to the ordinary 
 shawl-.straj). The portfoHo should contain a number of double sheets 
 of paper of about 11 x 17 inches. Xothinji; better can be ol)tained than 
 single i)ages of an ordinary New York daily newsi)aper once folded. 
 Within this fold the specimen, with tag attached, is to be laid, its leaves 
 and flowers as straight as can be, one or more of each turned with the 
 face, and others with the backs uppermost. While being carried in the 
 portfolio, they should be subjected to strong pressure to i)revent 
 wrinkling, and none of the parts must be allowed to project beyond the 
 edges of the paper. 
 
 Within twenty-four, and nnich better within six or eight hours of 
 the time of collection, the folds, with specimens contained, are to be 
 transferred to the dryers. At this time, each specimen should be gone 
 over, its leaves and flowers perfectly straightened out and arranged 
 in the position desired when dry. It is often desirable to introduce 
 several thicknesses of bibulous paper inside of the specimen sheets, so 
 as to make the entire thickness correspond with that of any excessively 
 thick portion of the specimen, such as a large root, fruit or tuber. 
 
 The drjers are to consist of some thick bibulous paper. When little 
 collecting is to be done, blotting paper is desirable, but when collecting is 
 upon an extensive scale, this is far too expensive and })erishable. Various 
 forms of dryers of excellent quality are for sale by the botanical supply 
 houses, but, in drying on a large scale, it has been found possible to 
 effect considerable saving by improvising them out of some suitable 
 material. The author has found the best method to be to obtain rolls 
 of thick, gray house-sheathing paper, 30 inches in length. This may 
 then be cut into 12-inch lengths, and folded to a size of 12 x IS inches. 
 When the amount of the material drying is large, it is better cut in 
 24-inch lengths and folded to 24 x 18 inches. Dryers of this size will 
 then accommodate two specimen sheets lying side by side. There are 
 so many varieties and qualities of house-sheathing on the market, that 
 careful selection is necessary. For plant-dryers it should be free from 
 mineral and coloring matters, tar and sizing, and its quality should be 
 tested by its ability to take uj) moisture readily. As a general state- 
 ment,* it may be said that that grade ordinarily denominated "poor" by 
 builders should be sought. The numl)er of dryers between two layers 
 of s])ecimens should be determined by the auKHUit of herbage possessed 
 by the latter, by the condition of the weather and climate, the facilities 
 for frecjuent changes of dryers and other similar conditions. In hot, 
 
230 THE COLLECTION OF BOTANICAL SPECIMENS 
 
 dry weather only one folded dryer is required for ordinary herbaceous 
 plants of temperate climates, provided the dryers are changed twice 
 or even thrice a day. In bad weather, or with thick, water-laden speci- 
 mens, or when the plants must remain more than twenty-four hours in 
 the dryers without change,- four folded dryers are required. By using 
 a large number of dryers in the best of weather, it is frequently possible 
 to dry ordinary specimens with but one change of dryers ; or even without 
 change, to secure specimens of the first quality. 
 
 Powerful pressure should next be applied. Weights, screws or levers 
 may be employed for this purpose, but no other method is equal to 
 the use of straps. These should be made of the heaviest and best 
 leather obtainable, should be li or 1^ inches in wddth and provided 
 with a large strong buckle, the holes not more than two inches apart 
 and punched to within two feet of the buckle. The length of the straps 
 should be proportional to the size of the bundle drying. For extensive 
 collecting, straps of 8 feet are required. The straps should be laid only 
 a few inches apart and the bundle laid upon them so that the buckle 
 barely projects from under the edge. The straps should be drawn 
 firmly into place without drawing the buckles from their place. The 
 operator now stands upon the bundle and stamps it firmly at all points, 
 so that no parts of the specimens are left without a firm application 
 of the dryers. The straps are then drawn as tightly as possible and 
 secured. A strong man can thus secure pressure of 500 or 600 pounds, 
 all of which is required for a pile of dryers two feet or more in height. 
 Even then it will be found, after the lapse of two or three hours, that 
 the pressure has become almost completely relaxed, owing to the wilting 
 and shrinking of the specimens, and the straps must be tightened. 
 The pile should now be stood upon the end on a dry stone or wooden 
 support, a pole frame being best. The flat side should be exposed to the 
 sun, or quite as good, to the heat of the kitchen range. When possible, 
 the dryers should be changed twice a day for the first day or two. The 
 dryers into which the sheets are to be transferred should be perfectly dry 
 and if possible hot from the sun. When it is not possible to expose them 
 to the sun just previous to making a change in the morning, they should 
 be wrapped tightly in a rubber cloth when brought in from the sunshine 
 of the previous afternoon, as dryers not thus protected will absorb a 
 considerable amount of moisture during the night. It is to be con- 
 sidered that the first hour in perfectly dry, hot dryers contributes quite 
 as much to the beauty of the specimens as the succeeding five hours. 
 
 In making the change, the specimen sheets are to be transferred to 
 
MOUNTING THE SPECIMENS ^31 
 
 the fresh drj'ers without opening. Under the ahove treatment, in hot 
 and very dry weather, most specimens will he dried i)erf'eetly in ironi 
 three to four days. Upon the tahlelands of Mexico and similar localities 
 only half of this time is required. Many plants, such as orchids or 
 cactuses, may require all summer for drying and are even frequently 
 worn out in the ])rocess of changing before they become dry. Such 
 plants may be dipped for an instant in boiling water l)efore being dried. 
 This process, while it greatly expedites drying, is apt to make the 
 specimen turn black. 
 
 Great judgment is required to avoid regarding a specimen as dry 
 before it really is so. The test is to see that any part will snap off in 
 attempting to bend it. Even after the specimens are perfectly dry they 
 should not be sealed up at once, as they are liable to undergo a sweating 
 process during the succeeding day or two. They should be tied tightly 
 in bundles and these bundles exposed to the sun for an hour or two on 
 several successive days, after which they may be sealed up, a good 
 method being to wrap them tightly in waxed paper, this protected by 
 hea\ier ])a])er, for transportation through a moist climate. 
 
 Poisoning the Specimen. — ^^arious methods have been resorted to 
 for poisoning specimens so as to make them proof against the attacks 
 of the small insects which infest the herbarium, but in no case have the 
 results proved permanent. Arsenical and mercural solutions have been 
 most employed. Upon the whole, a saturated alcoholic solution of 
 corrosive sublimate is the most satisfactory poisoning agent. Theo- 
 retically, the corrosive sublimate soon becomes converted into calomel, 
 but in practice its effects, if it be thoroughly applied, last for a great 
 nian.\- years. It may be poured upon the specimen, applied with a brush, 
 hea\ ily sprayed from an atomizer, or the specimen dipped into it. It 
 is to be treated as a very dangerous poison, not only internally, but 
 highly irritating to eyes, nose, and lungs and capable of poisoning by 
 inhalation of the spray. 
 
 When insects are found attacking mounted si)ecimens, the latter 
 should be enclosed in a tight case and subjected for some hours to the 
 vai)or of carbon disuli)hide. 
 
 Mounting the Specimens. — For permanent mounting in the herbarium, 
 sheets of standard size (Kiixllf inches) should be used and the 
 l)ai)er should be white and very lieaAy. ^Fuch ])aper now made of 
 wood-pulj) (piickly becomes yellow or brown, and scrupulous care to 
 avoid this quality should be taken. The specimens are to be secured 
 by the use of white glue applied over the entire surface and the stems 
 
232 THE COLLECTION OF BOTANICAL SPECIMENS 
 
 and branchlets should also be strapped down with strips of gummed 
 linen. Before attaching a specimen to the sheet, it should be carefully 
 examined to see that it exhibits both surfaces of the leaves, as well as 
 both the inner and outer surfaces of the flowers. Finally, an appropriate 
 label is to be gummed to a convenient part of the sheet, preferably to 
 the lower right-hand corner. 
 
 Wood specimens and other parts which cannot be attached to the 
 sheets may be preserved in suitable boxes or cabinets, according to 
 the taste and means of the collector. In all such cases, careful reference 
 should be made upon the label of each part of a specimen to the existence 
 of the other parts elsewhere. 
 
 Collecting Specimens for Immediate Examination in the Fresh State. — 
 For this purpose, various forms of tin case, commonly known as vascu- 
 lums, are provided. In these cases, specimens placed without free 
 access of air and light and without the addition of anything more than 
 their natural moisture, may be preserved perfectly for many days. In 
 the absence of proper vasculum, any tin pail or tin })ox with a tightly 
 fitting cover may be used. The author has found it very convenient 
 to carry with him a square yard of thin rubber cloth, which may be 
 folded tightly and carried in the pocket without any inconvenience, 
 and used when occasion requires. 
 
INDEX 
 
 Numbers in parenthesis indicate figure numbers; outside of parenthesis, pages. 
 
 Abortion (38), 38 
 
 of septa (230), 106 
 
 of theca, 68 
 Abruptly acuminate (508, etc.), 183 
 Absinthium, al<;ene of (76) 
 Absorbing roots, 160 
 Acacia leaf (563) 
 
 phyllode (562) 
 Acaulescent, 164 
 Accessory fruit, 103 
 
 parts, 103 
 Accrescent, 61 
 
 parts, 103 
 Accumbent cotyledons (413), 125 
 Aceroso leaf (492), 179 
 Achenium (74-80, 342), 121 
 Achillaea leaf (556) 
 Achlamydcous, and symbol for, 33 
 
 ovules, 69 
 Aconite flower (108) 
 Acorus inflorescence (586) 
 
 rhizome (452) 
 
 seed (382) 
 Acropetal anthotaxy (582, etc.), 201 
 Active period in flowers, 93 
 Aculeate stem (436), 165 
 Acuminate (511), 182 
 Acute, 183 
 Acyclic flowers, 43 
 Adelphism, 66 
 Adenium flower (55) 
 Adherent calyx (56), 44 
 Adhesion (54-57), 43, 51 
 Adnate anther (126), 62 
 
 disk (253, 266), 73 
 
 leaf (477), 176 
 
 stii)ulcs, 174 
 Adnation (54-57), 43 
 Adonis flower (17) 
 Adventitious bud, 169 
 
 roots, 160 
 Aerial roots, 160 
 
 stems, 162 
 Aeschynomene fruit (351), 124 
 Aesculus leaf (547) 
 Aestivation (120-125), 59 
 Aeterio (304-305), 126 
 Affinities, 19 
 
 Agarics, 210 
 
 Agglutination, 43 
 
 Aggregate fruit, 105 
 
 Agricultural botany, its departments, 19 
 
 Agrimonia leaf (557) 
 
 Agrimony leaf (557) 
 Agrostology, 19 
 Ailanthus leaf (508) 
 Akebia seed (394) 
 Akene (74-80, 344), 121 
 Ala (110), 69 
 Albumin, 128, 132 
 Albuminous seeds, 128 
 Alburnum, 144 
 Alchemilla ovary (179) 
 Alder inflorescence (15) 
 Algae, 211 
 
 Allophylus disk (261) 
 Alnus inflorescence (15) 
 I Aloe stamen (168) 
 Alternate leaves (571), 196 
 Alternation of generations, in crypto- 
 gams, 207 
 
 of position, law of, 41 
 Ambrosia root (439) 
 Anient (8, 11, 15), 202 
 Ampelopsis disk (459), 166 
 Amphitroi)ous, 81 
 Amplexicaul leaf (479), 176 
 Analogies, 19 
 Analogues, 19 
 
 Analysis of flower, chai)ter on, 86 
 Anatomy defined, 17 
 
 gross and mimite, 18 
 AnatrojKJUs ovules (242), 81 
 Androecium, chapter on, 62 
 Anemophilous flowers, 90 
 
 cross-pollination in, 90 
 Angiospermae, 219 
 Angiospermous gynaecia, 70 
 Angularly ovate, 181 
 Annual leaves, 175 
 
 rings, 144 
 
 roots, 158 
 
 stems, 161 
 Annular rhizomes, 164 
 
 stigma (210-215), 74 
 Antennaria leaf (503) 
 Anteposition, 42 
 Anterior side of flower, 41 
 
234 
 
 INDEX 
 
 Anther (12), 31 
 
 attachment of (126-133), 62 
 construction of, 62 
 cross-section of (14) 
 dehiscence of, 65 
 foi'ms of, 62, 64 
 Antheridia, 213 
 Antheridiuin of moss, 213 
 Anthcrozoids, 100, 209 
 Anthocarp, 105 
 
 Anthodium (343, 587), 122, 203 
 Anthology, 19 
 
 chapter on, 23 
 Anthophore (246), 82 
 Anthotaxy, chapter on (576-589), 199 
 Antidromy, 198 
 
 Ants Hving in inflated leaf (568), 195 
 Apetalous, 33 
 Apex of leaf for cUmbing (567), 194 
 
 forms of (506-515), 182 
 Apical placentae (235, 237), 77 
 Apiculate (517), 183 
 Apocarpous fruit, 105 
 
 pistil (219, etc.), 70 
 Apocynaceae, stigmas in (210, etc.) 
 Apothecia, 213 
 Apparatus for dissecting, 86 
 Appendages to androecium, 67 
 perigone, 57 
 seed (384, etc.), 131 
 stigma, 74 
 Apple (308), 119 
 Appressed teeth (531), 187 
 Arborescent stem, 165 
 Archegonium, 213 
 
 of moss (601), 213 
 Arctostaphylos anther (145) 
 Argenteous, 177 
 Aril, false, 129 
 true, 129 
 Arillode (381), 129 
 Arillus (375), 129 
 Arista (78), 58 
 Aristolochia flower (106) 
 Arnica, akene of (79) 
 Asarum anther (170) 
 
 leaf (495) 
 Ascending anthotaxy (582, etc.), 201 
 ovule (238), 78 
 radicle, 133 
 stem, 165 
 Asci, 213 
 
 Asclepias flower (150, 154) 
 fruit (349) 
 inflorescence (579) 
 poHination in (276) 
 poUinium (135) 
 Ash-fruit (339) 
 Asparagus stem (457), 167 
 Aspidium, 216 
 A.ssimilation, 17 
 Aster leaf (521) 
 
 Novae-angliae leaf (479) 
 Astragalus, ovary of (220) 
 Astronium ovary (178) 
 
 Asymmetry in androecium, 67 
 Atrojwus ovule (241), 81 
 Attachment of anther (126-133) 
 
 transportation of fruit (297, etc.), 
 109 
 Attenuate apex, 183 
 Attracting insects, provisions for, 91 
 Auricle (113, 153), 57 
 Auriculate (521), 184 
 Author-name, 223 
 Awl-shaped (499) 
 Awn (78), 58 
 Awns (295) 
 Axil of leaf (1) 
 Axile embryo (402, 403), 133 
 
 placentae (221, etc.), 76 
 Axillary placentae (221, etc.), 76, 77 
 Ayenia flower (90) 
 
 B 
 
 Bacteria, 210 
 
 Barbarea leaf (559) 
 
 Bark, color markings of, 152 
 
 defined, 150 
 
 fracture of, 151 
 
 importance in pharmacognosy, 150 
 
 inner surface, 152 
 
 layers of the, 150 
 
 nature of, 150 
 
 outer surface of, 151 
 
 ridges and furrows in (426), 152 
 
 section markings of, 151 
 
 wrinkled (425), 152 
 Barks, how to study, 150 
 Basal placentae (331), 77 
 
 style (179) 
 Base of leaf, forms of (516-523), 183 
 
 relation to petiole, 176 
 
 relation to plant stem (477-483), 176 
 Basinerved (528), 186 
 Basipetal anthotaxy, 200 
 Bast bundles of root, 142 
 
 fibers, 142 
 Bean, ovary of (219) 
 
 seed (395) 
 Beech nut (346) 
 Befladonna fruit (310) 
 Berberis, metamorphosis in (61) 
 Berry (281-310, etc.), 118 
 Bertholetia fruit (324) 
 Betula leaf (498) 
 Bicollateral bundle, 147 
 Bicuculla flower (27) 
 
 inflorescence (580) 
 Bidens fruit (300) 
 Biennial roots, 158 
 
 stems, 161 
 Bifurcating branching (435), 156 
 liijugate, 192 
 ]iiiai)iatc corolla (111), 56 
 Binomial, 222 
 Biology defined, 17 
 Bi-pinnate (563), 192 
 
INDEX 
 
 235 
 
 Bird-foot \iolct loaf (553) 
 Biternate (552), 192 
 Blackberry (305) 
 Black walnut fruit (345) 
 Bladder-wrack, 211 
 Bladdery inflated leaf (564) 
 Blunt (515), 1S3 
 Body of ovule (241, etc.) 
 Bonibax style (183) 
 Boneset leaf (476) 
 Borage, ovary (176) 
 Borago torus (250) 
 Bork, 140 
 
 Botanical analvsis, nature and method 
 of, 218 
 chapter on, 218 
 
 classification, chapter on, 218 
 Botany defined, 18 
 Botryosc anthotaxy, 202 
 Brace roots, 160 
 Bracts, 35, 195 
 Branches, abnormal position of, 154 
 
 of root, origin of, 153 
 
 of stem, arrangement of, 153 
 origin of, 153 
 Branching, diagram explaining (42) 
 Brazil nut fruit (324) 
 Brunnichia ovules (240) 
 Bryophyta, 213 
 Bud bulbs (464), 168 
 
 scales, modified leaves (7, etc.), 27 
 
 the (1, 4) 
 Buds, 157 
 
 classified, 169 
 
 wanting from some leaf-axils, 153 
 Bulb, axillary (464) 
 Bulbs (461-465), 161, 168 
 
 terminal (464) 
 Bullate (484), 178 
 Bundles, completion of, in root, 143 
 
 development of secondary, 143 
 Burdock fruit (301) 
 Buttercup akene (344) 
 
 leaf (540) 
 
 petal and nectary of (()3) 
 
 Cactus fruit (281) 
 Caducous, 61 
 Caju, pulp of (306) 
 Calabar bean (371) 
 Calamus inflorescence (586) 
 
 rhizome (452) 
 Calcar (65), 58 
 Calcaria, 69 
 
 Calesium fruit (279), 96 
 Calisaya bark, mature (427) 
 
 young (425) 
 Callirriioe bud (21) 
 
 flower (22) 
 
 the, 32 
 Callus (2), 25 
 Calyciilorae, 219 
 
 Calyptra, the (87-88), 52 
 Calyx circle, the double, 30 
 
 lobes, 32, 53 
 
 the, 32 
 Cambium circle (422), 143 
 
 cvlindor, 143 
 
 <l('vel()i)ment (422), 143 
 Campanulate (93), 54 
 Camponiancsia, embryo (400) 
 Campyluspcrinous (338), 121 
 Cami)vlotropous ovule (244), 81 
 Cancellate (485), 178 
 Cancscciit, 178 
 Capillary leaf, 179 
 
 style (190) 
 Capitahzation, 224 
 Capitate stigma (196), 74 
 Capitulum (578), 202 
 Capsicum, 118 
 Capsule (318-328), 125 
 
 of moss (599), 214 
 Cardamine (354) 
 Cardiosi^ermum (294) 
 
 seed (370) 
 Carina (110) 
 Carinate, 64 
 
 Carnivorous leaves (560, 561), 192 
 Carnose, 116 
 Carpel, 31 
 
 reverted to leaf (19) 
 Carpels, terminology for number of, 74 
 Carpology, 19 
 
 chapter on, 102 
 Carpophore (245, 247), 82, 120 
 Carrot fruit (288) 
 Caruncle (380, 382), 131 
 Caryophyllaceous flower (72), 57 
 Caryopsis (348), 123 
 Cashew, jiulp of (306) 
 Cassia anther (143) 
 
 fistula, 124 
 Castalia, metamorphosis in (62) 
 Castanea fruit (284) 
 
 leaf (524) 
 Castor-oil seed (380) 
 Catkin (8, 11, 15), 202 
 Cauda (115), 58 
 Cautlate anther (133) 
 Caulicle {ca in Figs. 400, etc.), 132 
 Ceiba anther (128) 
 Cell walls, 32 
 Cells, 32 
 
 development of new, 106 
 
 of fruit, abortion of, 106 
 Cellular dcvel()i)m(Mit, 138 
 Central cvlinder of root, 141 
 of stem, 146 
 
 placentae (221, etc.), 76 
 Centric embryo (402, 403), 133 
 
 placentae, 77 
 Centrifugal inflorescence (584) 200 
 
 radicle, 133 
 Centripetal anthotaxy (577), 201 
 
 radicle, 133 
 Cei)halanthus inflorescence (578) 
 
236 
 
 INDEX 
 
 Cerastium fruit (318) 
 Cercis leaf (528) 
 Chaetostoina stamen (155) 
 Chalaza (241, etc.), 80 
 Chambers (223), 76 
 Channelled petiole, 175 
 
 venation, 178 
 Checkerberry (303) 
 Chekan leaf (500) 
 Cherry flower (58) 
 Chestnut burr (284) 
 Chimaphila style (184) 
 Chondrus, 211 
 Choripetalous, 53 
 Chorisepalous, 53 
 Chorisis, 38 
 
 diagram explaining (42) 
 Ciliate (475), 178 
 Cimicifuga rhizome (448) 
 Cinchona, false, fruit of (323) 
 
 fruit (322) 
 
 seed (387) 
 Cineraria, pappus of (S3) 
 Cinereous, 177 
 Circinate, 60 
 
 inflorescence, 200 
 Circular anther (134) 
 Circumscissile dehiscence (320, 325, 326), 
 
 115 
 Cirrhiferous stem (431), 165 
 Cirrhose, 165 
 Chestnut leaf (524) 
 Cladoidia (457, 460), 166 
 Cladophylla (457, 460), 166 
 Clasping leaf, 175, 176 
 Classification of cryptogams, 210 
 Clavate, 64 
 
 style (182) 
 Claw (18), 33 
 Cleft (539), 188 
 
 perigone (92), 53 
 Cleistogamy, 96 
 Clematis bud (122) 
 
 leaf (569) 
 Climbing stem, 165 
 Close pollination, 90 
 
 sheath (465, B), 170 
 Closed collateral bundle, 149 
 Club moss (598), 215 
 Coalescence, 43 
 Coated bulb (462), 168 
 Coats of ovule (241, etc.), 79 
 Coccus (330, 334), 120 
 Cochlea (353), 124 
 Coelospermous (337), 121 
 Coffee flower (101) 
 Cohesion, 43 
 
 in androecium, 66 
 
 in perigone, 52 
 Cohorts, 219 
 
 Collateral ovules (219), 78 
 Collection of plants, chapter on, 226 
 Collective fruit, 105 
 Collinsonia leaf (494) 
 Colocynth flower (56) 
 
 Color in attracting insects, 92 
 Columella in mosses, 215 
 Column, 46 
 Commissure, 120 
 Complanate, 64 
 Complete flower, 33 
 Comi)lex inflorescence, 203 
 Compositae, pappus of (74-83) 
 Compound bulb, 168 
 
 inflorescence, 203 
 
 leaf (548, 554), 189 
 
 pistil (218, etc.), 70 
 Concentric bundle, 149 
 Conceptacle of algae (592), 213 
 Conducting tissue of style, 99 
 Confluent sutures (131, 132), 66 
 Conical style (181) 
 Connate-perfoliate (476), 176 
 Connation, 43 
 Connective (14), 31 
 
 modifications of (155-164), 68 
 Connivent anthers (92), 66 
 Consolidated stems (458, 460), 167 
 Constriction of perigone (100) 
 Continuous leaf base (482) 
 Contracted campanulate (95) 
 Convallaria anther (141) 
 
 leaf (526) 
 
 rhizome (447) 
 Convolute (120), 60 
 Coptis, petal and nectary of (64), 47 
 Coriaceous leaf, 177 
 Corm (463), 168 
 Corn-seed (369) 
 Cornu, 58 
 Corolla, 32 
 
 as a fruit wing (290) 
 
 lobes, 32, 53 
 Corona (116, 117, 150), 58 
 Corrugated, 60- 
 Cortex of stem, 145 
 Corymb (577), 202 
 Costae (527), 184 
 Costate, 64 
 
 Costinerved (529), 186 
 Cotyledons (cot. Figs. 400, etc.), 133 
 Coussarea disk (254) 
 Crataegus inflorescence (577) 
 Crateriform (103), 55 
 Creeping stem (445), 165 
 Cremocarp (247, 288), 120 
 Crenate (530), 187 
 Crenulate, 187 
 Cribrose tissue, 142 
 Cristate, 56 
 Cross-polhnation, 90 
 
 beneficial, 90 
 Crowded ovules (232), 78 
 Crown (116, 117, 150), 165 
 Cruciferous flower, 57 
 Crumpled, 60 
 Cryptogamic botan}^ 19 
 Cryptogams, alternation of generations 
 in, 207 
 
 chapter on, 207 
 
INDEX 
 
 237 
 
 CryptoKams, chissifiration, 210 
 
 comparison with pli;uuM-ot!;ain.s, 207 
 general characters of, 207 
 reproduction of, 209 
 the plant body in, 207 
 vegetation of, 209 
 
 Cucullate (lOS), 56 
 
 Cuneate (518), 1S4 
 
 Cupulato stifiina (200), 74 
 
 Curcuma (444) 
 
 Curvincrveil, 1S6 
 
 Cuspidate, 183 
 
 Cyclanthora anther (134) 
 
 Cycle of leaves, 196 
 
 Cyclic flowers, 43 
 
 Cylindraceous (29, 99), 54 
 
 Cylindrical, 54 
 
 Cyme (584), 200, 202 
 
 Cymose inflorescence (584), 200 
 
 Cymule, 201 
 
 Cynocrambe embryo (402) 
 
 Cyperaceae (588), 206 
 
 Cypripedium flower (112) 
 
 Cypsela (74-80), 122 
 
 Dalibarda loaf (530) 
 Danais seed (3S6) 
 Dandelion floret (41, 104) 
 
 leaf (558) 
 Datura fruit (282) 
 
 leaf (523) 
 
 ovary of (221, 223) 
 
 seed (379) 
 Deciduous, 61 
 Declined corolla (107) 
 Decompound, 190 
 Decumbent stem, 165 
 Decussate (573), 196 
 Defence in fruit, 107 
 Definite anthotaxy (576), 200 
 Deiiisce, 114 
 
 Dehiscence by pores (143, 328, etc.), 66, 
 116 
 
 forms of, 113 
 
 incomplete (318, etc.), 115 
 
 mechanism of, 115 
 
 of anther, 65 
 
 of fruit (315. etc.), 113 
 Dehiscent fruits, 113 
 Dehi.scing, 114 
 Deliquescent stem, 164 
 Delphinium, petal and nectary of (65), 
 
 47 
 Deltoid (49S\ 181 
 Dentate (n.'A), 1S7 
 Denticulate, 187 
 Departments of botanv, 18 
 Dermatogon (420), 139 
 
 structures from, 139 
 Descending anthotaxy, 200 
 
 radicle, 133 
 Descent of pollen tube (278), 100 
 
 Descriptive botany, 19 
 Determinate anthotaxy (576), 199 
 
 stems, 161 
 Dextrorse (125), 60 
 Diadelphous (146), 66 
 Diandrous, 62 
 Dianthus (18) 
 Dicldamydeous ovules, 80 
 Dichogamy, 94, 
 DichotoiDovis branching, 156 
 l)ir()tvl(>(ions (416, etc.), 133 
 DidviKimous (151), 67 
 Digitalis leaf (516) 
 
 Digitateiy veined leaf (527, 528), 186 
 Dimerous flower (27), 38 
 Dimorphism (273, 274), 96 
 Dinemandra flower (66) 
 Diodia stipules (474) 
 Dioecious flowers, 30 
 Dioeciously polygamous, 30 
 Dionacaleaf (561) 
 Diospyros fruit (280) 
 Dipteryx, 124 
 
 embrvo (405) 
 Direction'of ovules (233, etc.), 78 
 Disciflorao, 219 
 Discoid, 204 
 Disk flowers, 204 
 
 of anthodium (587, c) 
 
 the (260-266), 83 
 Dissection of flower, chapter on, 86 
 Dissemination by edible seed-coat. 129 
 
 by fixation, 129 
 
 by wind, 129 
 
 provisions for, 113 
 
 through seed, 129 
 Distinct i)arts, 44 
 Diurnal flowers, 93 
 Divergence of leaves, 197 
 
 of ovules, 77 
 Divid(Hl leaf (540, 559), 188 
 Divisions anil subdivisions of plants, 219 
 Dorsal awns (172) 
 
 dehi.scence (136), 65 
 
 spur (114) 
 Dorsifixed anther (127, 129) 
 Doubly serrate (531) 
 Dried specimens, how to dissect, 89 
 Drosera leaf (491) 
 Drupe (333), 118 
 Drupelet (305, a), 119 
 Drvmicarpus ovule (237) 
 Ducts, 142 
 Duplication, 38 
 Duramen, 144 
 Duration of leaves, 175 
 
 of perigone, 61 
 
 E 
 
 l"]c(i:\TUi(ALLY peltate (483) 
 Eccentric embryo (407), 133 
 
 ])lacentae, 77 
 Echites flower (100, 125) 
 
238 
 
 INDEX 
 
 Edible pericarp for transportation (303, 
 etc.), 109 
 
 pericarp not from flower, 109 
 
 I)()rtion of fruits, origin of, 110 
 
 s('{>cls, protection to, 109 
 P^ichornia leaf (5G4) 
 Elateriuin, dissemination of (314) 
 
 fruit (314) 
 Eleutheropetalous, 53 
 Eleutherosepalous, 53 
 Eleutherous parts, 44 
 Elliptical (488, 489), 179 
 Elm fruit (287), 98, 121 
 Elongation of internodes of torus (248, 
 
 etc.) 
 Emarginate leaf (509), 182 
 Embryo, development of (364-368), 127 
 132, 136 
 
 forms of, 134 
 
 nourishment of, 128 
 
 parts of, 132 
 
 position of, 133 
 
 protection to, 129 
 
 requirements of, 127 
 Emergences (148), 156 
 Empirical formulae, 41 
 Enation (63), 47 
 Endocarp, 105 
 Endoderm, 140 
 Endophloeum, 150 
 Endopleura, 129 
 Endosperm, 127 
 Entomophilous flowers, 90 
 
 cross pollination in, 91 
 Epicalyx (16, 21-24), 34 
 Epicarp, 105 
 Epicotyl, 138 
 Epidermis (422), 139 
 
 of stem, 145 
 Epigynous (56), 44 
 
 disk (254), 73 
 Epigyny (56), 44 
 
 apparent or false (59, 60) 
 Epilobium seed (384) 
 Equally pinnate (554), 192 
 Equisetaceae, 215 
 Equitant leaves, 176 
 Erect ovules (233), 78 
 Ergot, 210 
 
 Erigeron, akene of (80) 
 Eriosphaera, pappus of (82) 
 Erodium (245) 
 Essential organs, 32 
 
 protection for, 32 
 Etiolated leaf, 193 
 Eucalyptus bud (87) 
 
 leaf (504) 
 
 fruit (319) 
 Eucharidium seed (383) 
 Euonymus, 131 
 
 ovule (236) 
 Eupatorium anther (169) 
 Even pinnate (554), 192 
 Evergreen leaves, 175 
 
 plants, 175 
 
 Exaggeration of growth, 49 
 Exalbumiiious seeds, 128 , 
 Excurrciit stem, 164 
 Exine, 99 
 Exocarp, 105 
 Exodermis, 140 
 Exo])lil()eum, 1.50 
 Ex()j)lcuni, 129 
 Exsert or exserted, 69 
 Exstipulate leaves, 174 
 Extine, 99 
 
 Extrorse attachment, 64 
 dehiscence, 65 
 
 Fagus fruit (346) 
 Falcate leaf (504), 182 
 False septa (220), 76 
 Families of plants, 219 
 Fascicle of flowers, 202 
 Fascicled leaves, 198 
 
 roots, 160 
 Female flower (9), 29 
 
 gametophyte (277), 99 
 Ferns, 216 
 
 oospore (602), 216 
 Fertilization, 90, 98 
 
 in cryptogams, 209 
 Fibers, 142 
 
 Fibrous roots (446), 160 
 Fibro-vascular bundles of roots, 142 
 
 tissue not from periblem, 139 
 Fig fruit (362) 
 
 pulp of (311) 
 Filament (12), 31 
 
 forms of, 64 ' 
 
 Fihces, 216 
 
 Filiform leaf (491), 179 
 Fission, 210 
 Fissured corolla (96) 
 Fistulous stems, 167 
 Fixation of seed, 129 
 Fixing roots, 160 
 Flabellately nerved (527), 186 
 Flax ovary (224) 
 Fleshy leaf, 177 
 
 ' roots, 160 
 Flexuous branching (433), 155 
 Floating leaves, 195 
 Floral envelopes, 33 
 
 leaves, 195 
 Florets, 204 
 Flower, a modified branch (9, etc., 20), 28 
 
 cluster, a modified branch (8, etc.), 
 27 
 
 clusters (576-589), 199 
 
 dissection and analysis of, 86 
 
 explained and defined, 28, 34 
 
 general nature of, 23 
 
 some imperfect, 29 
 Flowerless plants, 207 
 Follicle (349), 123 
 
INDEX 
 
 239 
 
 Foramen of ovule, 79 
 
 Forms, 220 
 
 Fornicate corolla (119), 58 
 
 iM.vcolate, 204 
 
 Frankcnia embryo (403) 
 
 Krasera petal (07) 
 
 Fraximis (513) 
 
 Free central placenta (230) 
 
 parts (47) 
 Frond, 21G 
 
 of ferns, 216 
 Frondosc stem (456), 167 
 Fructification defined, 102 
 
 parts useful in, 103 
 
 parts useless in, 103 
 
 results of, 102 
 Fruit and frynaecium, relations between, 
 104 
 
 classification, chapter on, 116 
 key to, 116 
 principles of, 116 
 
 defense in, 107 
 
 function and structure of, cliaptcr 
 on, 102 
 
 structviral and pliysioloj^ical senses 
 of, 104 
 
 transportation by water, 107 
 miscellaneous. 111 
 prevention of (313), 111 
 Fruits, fixation after transportation, 
 112 
 
 kinds of (279-363) 
 
 one-seeded (286, etc.) 
 
 table of classes, 116 
 Fruit-wings, mor])hology of, 108 
 Fruticose stem, 165 
 P'ueus (592, 593), 211 
 
 sexual organs of (593) 
 Fugacious, 61 
 P^unctions, 17 
 Fungi, 210 
 
 Funiculus (241, etc.), 79 
 Funnel-shaped (97), 54 
 Fusiform (442), 160 
 
 Galbalus (359), 126 
 Galeate (108), 56 
 (!all cone (5) 
 (Jalopina style (187) 
 Gametes of Fucus (592) 
 Gametophyte, female (277), 99 
 
 in cryptogams, 207 
 
 male (278), 100 
 
 of moss (599) 
 Gamocarpous pistil (218), 70 
 Gamopetalous, 53 
 Gamoscpalous, 53 
 (Jaultheria leaf (532) 
 Gemma, 157, 209 
 (i(MiiMKiti()ii, 209 
 Genera, 219 
 
 Genera of plants, number of, 219 
 
 Generic name, 222 
 
 Geranium, diagram of fiower (43) 
 
 flower (30) 
 
 leaf (546) 
 Germination, conditions for, 137 
 
 figures of (416-419) 
 
 nature of, 137 
 
 of microspore (278), 99 
 Gesncria rhizome and roots (446) 
 Geum fruit (302) 
 Gibbous corolla (107), 56 
 Glabrous, 177 
 Gladiolus conn (463), 168 
 Glands (66-70), 47, 122 
 
 petiolar, 175 
 Glans (345) 
 Glaucous, 177 
 Gl(>ditschia leaflet (554) 
 Cileichenia, 216 
 Gleof-apsa (590) 
 CJlol)ose, 54 
 Globular, 54 
 Glomerule, 202 
 Glumaceae (588, 589), 205 
 Glumes (588, 589), 205, 206 
 Glycyrrhiza (146) 
 Gonophore (249), 82 
 Gooseberry leaf (539) 
 Grafting, 25 
 Grain (348), 123 
 Gramineae (589), 205 
 Graminology, 19 
 Grape, branching in (431) 
 
 position and origin of fruit (432) 
 Grass, flower of (267) 
 
 leaf (465 A) 
 
 inflorescence (589) 
 
 like inflorescences (588) 
 Gratiola stamen (167) 
 Green rose, 46 
 Gregarious plants, 91 
 Grindelia, akene of (78) 
 Gross anatomy, 18 
 Ground-tissue of stele, 141 
 Guaiacum ovule (235) 
 Guarea (147) 
 Guttiferales, 219 
 Gynmospermae, 219 
 Gymnospermous gynaeciiuii, 70 
 
 ovule, 98 
 
 pistil (174, 175), 70 
 Gymnosperms, germination of (406 ~) 
 Gynaecium and fruit, relation between, 
 104 
 
 chapter on, 70 
 
 composition of, 29 
 
 method of examining, 71 
 
 symbols and fornuilae for structure 
 of, 29 
 Gynandrous (54) 
 Gynandry (54, 55), 46 
 Gynobase (250), 82 
 Gynocardia embrvo (401) 
 Gynophore (249, 252), 82 
 
240 
 
 INDEX 
 
 Halberd shapod (522), 1S4 
 Hamamelis leaf (505, 536) 
 Hanetio seed (375) 
 Hastate (522), 184 
 Haustoria, 160 
 Head of flowers (578), 202 
 Heart-wood, 144 
 Helianthemum style (182) 
 Heliocharis seed (396) 
 
 style (188) 
 Henbane fruit (363) 
 
 seed (377) 
 Hepatica, flower (23, 24) 
 
 leaf (545) 
 Hepaticae, 210 
 Herbaceous leaf, 177 
 Herbs, 161 
 
 Hermaphrodite flowers, 31 
 Hesperidium (329), 118 
 Heterochromous, 204 
 Heterogamous, 204 
 Heterosporous ferns, 216 
 Hexaptera (356) 
 Hibiscus bud (121) 
 Hilum (370, 371), 80, 129 
 Hippocratea disk (263) 
 Hippurus flower (25, 26) 
 Hirsute, 178 
 Hispid, 178 
 Histology defined, 18 
 Homochromous, 204 
 Homogamous, 204 
 Homologies, 19 
 Homologues,,19 
 Homonym, 225 
 Homosporeae, ferns, 216 
 Homosporous ferns, 216 
 Honey-locust leaflet (554) 
 Hop-fruit (292, 361) 
 Horizontal anther (129), 63 
 
 ovules (234), 78 
 
 radicle, 133 
 Horn (150), 58 
 Horse chestnut leaf (547) 
 Horse-tails, 215 
 Horticulture, 19 
 Houstonia flower (273, 274) 
 Hypanthium, 45 
 Hypericum seed (374) 
 Hypocotyl, 138 
 
 Hypocrateriform (101, etc.), 54 
 Hypocraterimorphous (101, etc.), 54 
 Hypoderm (422), 140 
 Hypogynous (47), 46 
 Hypogyny (47), 46 
 Hyoscyamus anther, 136 
 
 fruit (362) 
 
 seed (377) 
 
 Illipe, flower of (44) 
 Imbricate (123, etc.), 60 
 
 Iinpari-pinnate (555), 192 
 Inipcrfcction, degrees of, 31 
 Inipres.'^ed venation, 178 
 Inci.sed (540, 546), 189 
 Incumbent cotyledons (412), 135 
 
 anther (127), 63 
 Incurved teeth, 187 
 Indefinite numljer of parts, 40 
 Indehisccnt fruits, 113 
 Indeterminate anthotaxy (582, etc.), 201 
 
 stem, 161 
 Indumentum, 177 
 Induphcate (122), 59 
 Indusium, 217 
 Inequilateral leaf (505) 
 
 base (521, 523), 181 
 Inferior ovary (56), 45 
 Inflorescence leaves, 204 
 Inflore.scences (576-589), 199 
 Infundibular (97), 54 
 Inga, 123 
 
 Innate anther (130), 63 
 Inner lip (111) 
 Insect visits, 94, 97 
 Internode (1) 
 
 Internodes, growth of, 153 
 Interpetiolar stipules (474), 174 
 Interruptedly pinnate (557), 192 
 Intine, 99 
 Introrse attachment, 64 
 
 dehiscence, 65 
 
 stigmas (191), 73 
 Intruded leaf base (519), 184 
 Involucre (587, a), 205 
 
 defence in fruiting (284), 107 
 Involute, 60 
 Ipomoea (91) 
 
 bud (120) 
 Iris fruit (315) 
 
 rhizome (451) 
 Irregular disk (261) 
 
 suppression, 39 
 Irregularity, antero-posterior, charac- 
 terizes development, 43 
 
 causes of, 43 
 Isomerous, 37 
 
 Jaborandi leaf (525) 
 Jalap, roots of (437) 
 Jeffersonia fruit (327) 
 Jugae, 192 
 Juniper fruit (359) 
 Jussiaea fruit (321) 
 
 Kalmia flower (103) 
 Keel (110), 57 
 Kefir grains, 210 
 Kelp, 211 
 
ISDKX 
 
 241 
 
 Lahiatae, "jG 
 
 fruit of (334) 
 Laciniate (540), 189 
 Ladenbergia fruit (323) 
 Lamina, 2(3 
 
 of petal (18) 
 Laminar stigmas (203-20")), 74 
 Lanceolate (496), 181 
 Lance-ovate (497), 189 
 Lasioi)Ogoii, i)ai)pus of (81) 
 Latent 1)U(1, lt)9 
 Lateral chorisis, 40 
 
 primaries, 184 
 
 style (177, 178) 
 Latli3-rus leaf (507) 
 Laurel flower (103) 
 Layering (2), 25 
 Leaf, anatomical elements of, 173 
 
 axil (1), 24 
 
 base, relation to petiole, 176 
 
 relation to plant stem (477-483), 
 176 
 
 blade, development of (469) 
 
 composition of, 26 
 
 cvde, 197 
 
 .U'velopment of (4, 466-472), 170 
 
 dvu'ation of, 175 
 
 margin (530-537), 186 
 
 origin of (4), 153 
 
 I)arts of (3), 26 
 
 regions of (468) 
 
 sheath, 170 
 
 surfaces, 172 
 
 classified, 177 
 
 texture, 177 
 Leaflets, 190 
 Leaves, arrangement of, li)6 
 
 as climbing organs, 195 
 
 carnivorous, 192 
 
 floating, 195 
 
 modified, 192 
 Lecanosperma seed (391) 
 Legume (350), 123 
 Lenma stem (456) 
 Lemon (329), 118 
 Lens seed (390) 
 Lepidote, 178 
 Lespedeza leaf (549) 
 Leucothoe corolla (95) 
 Lichen thallus (598) 
 Lichens (598), 213 
 Ligulatc (104), 55 
 
 Ligule, d(>vcloi)menl of (465 A), 172 
 Ligulitlorate. 204 
 Lily bulb (461) 
 Limb of petal (18) 
 
 of perigone (94), 54 
 Lindera leaf (501 ) 
 
 stigma (191), 73 
 Lipped perigones, 56 
 Liriodendron leaf (507) 
 Lobed (543, etc.), 188 
 
 disk (265) 
 16 
 
 Lobed perigone (97) 
 Lobelia (96, 153) 
 
 inflorescence (583) 
 Lobing of carpels (216, etc.) 
 Locelli (138), 31 
 Locellus (14) 
 Lochnera flower (124) 
 Loculicidal dehiscence (315), 115 
 Loment, 124 
 Lonicera leaf (5 10) 
 Lower lip (111), 56 
 Loxopterygium (178) 
 Lycopodiaccac, 216 
 Lycopodiuiu (()04), 216 
 Lyrate (559), 192 
 Lysimachia flower (84) 
 
 M 
 
 Macrosporangium, 30 
 Macrospores, 29 
 
 germination of (278) 
 Macrosporophyll, 30 
 Macrosjiorophj^te, 30 
 Maculate, 178 
 iMaerna (249) 
 Magnolia anther (126) 
 
 diagram of flower (35) 
 
 gynaecium (251) 
 Main root (439), 158 
 Male cell, 30, 100 
 
 fern, 216 
 
 flower (12), 30 
 
 gametophyte (278), 100 
 Malpighiaceae (342) 
 Malva anther (1-31) 
 Malvales, 219 
 
 Many serialled ovules (227) 
 Maple fruit (340), 121 
 Marcescent, 61 
 Margin of leaf (530-537) 
 
 of perigone, 54 
 Marginal dehiscence (141), 65 
 Martiincd petioles, 175 
 Marginicidal dehiscence (317), 115 
 Mascagnia fruit (342) 
 Median chorisis, 40 
 Medical botany, scope of, 19 
 Meihilla, 141, 146 
 Medullary rays (421, 423), 141 
 
 development of .secondary, 144 
 Melon, 118 
 Members, 17 
 Membranaceous leaf, 177 
 Menispermum leaf (483) 
 
 seecl (397) 
 Menziesia (137) 
 IMericarp (335, etc.), 120 
 Meristem, 136 
 Meristematic tis.sue, 136 
 Merten.sia (118, 119) 
 Mesoearp, 105 
 Mesophloem, 150 
 
242 
 
 IDDEX 
 
 Metamorphosis, 46 
 Microscopes for dissecting, 86 
 Microscopical botany, IS 
 Microsporangium, 30 
 Microspore, development of, 05 
 
 germination of (278), 99 
 
 structure of, 99 
 Microspores (14), 30 
 Microsporophyll, 30 
 Microsporophyte, 30 
 Micropyle (241, etc.), 79, 129 
 jMiddle primary, 184 
 Midrib (524, a), 184 
 Millefoliate leaf (556) 
 Mimulus flower (94) 
 Minute anatomy, 18 
 Mitchclla flowers (269, 270) 
 Mitranthes (88) 
 Mixed bud, 169 
 
 praefloration, 61 
 Modification of connective (155-164) 
 Modified leaves (560-569), 192 
 
 stems, 165 
 Modiola ovary (216) 
 Monadelphous (147), 66 
 Monandrous (25) 
 Monks-hood flower (108) 
 Monocarpellary pistil (219, etc.), 71 
 Monocarpous, 158 
 Monochlamydeous and symbol for, 
 
 33 
 Monocotvledonous stem structure (424) 
 
 149 
 Monocotyledons (404), 133, 219 
 Monoecious flowers (15), 30 
 Monoeciously polygamous, 31 
 Monomerous flower (25, 26), 38 
 Monopetalous, 53 
 Monopodial stems, 154 
 Monosepalous, 53 
 Monospermous fruits (286, etc.) 
 Monstrosities, 46 
 Morphology, 19 
 Moonseed leaf (483) 
 Moss (595), 214 
 
 antheridium, 215 
 
 antherozoids, 215 
 
 archegonium, 215 
 
 capsule (595), 214 
 
 development of sporophj'te, 215 
 
 gametophj'te (595), 214 
 
 sporophyte (595), 214 
 development of, 215 
 Mosses, 214 
 Mucronate, 183 
 Mullein leaf (477) 
 Multi-jugate, 192 
 Multiple fruit, 105 
 
 primary root, 159 
 Musci, 214 
 
 Mustard, androecium of (33) 
 Mycelium, 210 
 Mycology, 19 
 Myristica seed (381) 
 
 N 
 
 Naked bud, 169 
 
 flower, 33 
 
 ovules, 80 
 
 seeds, 129 
 Napiform (441) 
 Narcissu.s (116) 
 
 Nectar and nectaries (63, 65), 93 
 Needle-shaped leaf (492) 
 Nelumbium torus (252) 
 Nepenthes leaf (560) 
 
 seed (392) 
 Nervature, 184 
 Nerves (529) 
 
 Netted-veined leaves (524, etc.), 185 
 Neutral flowers (268), 33 
 
 in attracting insects, 92 
 Nicandra (113) 
 Niederlinia seed (373) 
 Nocturnal flowers, 93 
 Nolina seed (393) 
 Nomenclature, chapter on, 222 
 Non-essential organs, 32 
 Notched apex (507) 
 Nuca (345), 123 
 Nucellus (241, etc.), 79 
 Nucleus sheath (424), 150 
 Nucula (330, 334), 120 
 Numerical plan indicated by diagram, 
 (43), 40 
 
 formula, 41 
 
 symmetry, terminologv of, 37 
 Nut (345), 123 
 Nutlet (330, 334), 120 
 Nutmeg (381) 
 
 section of (399) 
 Nux vomica seed (372) 
 Nymphaea leaf (473) 
 
 Oakesia leaf (480) 
 Obconical style (183) 
 Obcordate (506), 182 
 ()l)lanceolate (502), 181 
 Obhque base (521, 523), 56, 181 
 
 corolla (107) 
 
 leaf (505) 
 Oblong (488), 179 
 
 elHptical (488), 179 
 Obolaria (232) 
 (^bovate (501), 181 
 Obsolctely (532), 188 
 Obtuse (511, etc.), 183 
 Ochrea, development of (472), 172 
 Odd-pinnate (555), 192 
 Odor in attracting insects, 92 
 Oenothera (89) 
 
 anther (129) 
 
 flower (29) 
 Ofi-set, 162 
 Olea flower (31, 32) 
 OUve flower (31, 32) 
 
INDEX 
 
 243 
 
 ( )nc-fcll(«(l anthers (10'), 166), 6S 
 
 ( )ii(,"-lipi)0(l roiolla (lOf)) 
 
 ( )ii(>-s('rialletl ovules, 78 
 
 Onion bulb (402) 
 
 Oogonia, 213 
 
 ()6si)hore, 213 
 
 C)o.s]jore (277) 
 
 Oospores in algao, 213 
 
 ()l)aqup leaf, 177 
 
 Open canii)anulate (91) 
 
 eollateral bundle, 146 
 
 perigone (120) 
 
 sheath (465, A, etc.), 170 
 Opposite leaves, 106 
 Opuntia fruit (281) 
 
 stem (458), 167 
 Orange, 118 
 
 leaf (550, 551) 
 Orbicular leaf (493), 180 
 Organic bodies, characters of, 17 
 
 kingdom, 17 
 
 matter, 17 
 Organogeny, 19 
 Organography, 19 
 Organs, 17 
 
 Ortliospornious (335), 121 
 Ortliostacliy (573), 196 
 Orthotropous ovule (241), 81 
 Outer lip (111) 
 Outgrowth (63), 47 
 Outgrowths (436), 156 
 Outline of comjjound leaf, 179 
 
 of leaf, 179 
 Oval (489, 490), 179 
 
 elliptical (489), 179 
 Ovary (9, 10), 32 
 
 defence on fruiting (282) 
 
 first plan of structure (219, etc.), 76 
 
 second plan of structure (225, etc.), 
 77 
 Ovate (494), 179 
 
 lanceolate (497), 189 
 Ovoid, 54 
 Ovule (277, 278) 
 
 changes by fertilization, 127 
 
 connection between stigma and, 99 
 
 internal structure of (277), 98 
 
 of gj-mnosperms, 98 
 
 parts of (241-244), 79 
 Ovules (10), 31 
 
 direction of (233, etc.), 78 
 
 forms of (241, etc.), 80 
 
 number of, 78 
 
 position of, 78 
 
 series of, 78 
 
 structure of (241-244), 79 
 Oxalis leaf (.506) 
 
 Paedkria stvle (185) 
 
 Palate (94), 58 
 
 Palets, 206 
 
 Palm fruit, abortion in (285) 
 
 Palmate (.548), 190 
 
 Falmately compound (547), 190 
 
 veined leaf (.527, 528), 186 
 Palmatifid, 189 
 Panicle, 203 
 Paniculate, 203 
 Panicum (514) 
 Papaw (309), 118 
 Papilionaceous (1,10), 57 
 Papillose, 178 
 
 stigma (275) 
 Pappus, the (74-83), 51 
 Parenthetical names, 223 
 Parietales, 219 
 
 Parallel veined leaves (526), 185 
 Parietal i)lacentae (225, etc.), 77 
 Pari-pinnate (554), 192 
 Parted (538, 546), 188 
 
 perigone (84) 
 Passiflora (116) 
 
 fruit, 125 
 Paullinia ovule (234) 
 Pea-fruit (350) 
 
 leaf (567) 
 Peanut (313), 112 
 Pedate (553), 191 
 Pedicel (.584, c), 199 
 Pedicularis leaf (538) 
 Peduncle (a in 576 and 583), 199 
 Pelargonium, flower of (48) 
 Pellucid-punctate leaf, 177 
 Peltate leaf, 176 
 
 stigma (183, 198), 74 
 Pendant stem, 165 
 Pendulous ovules (239), 78 
 Penninerved leaf (524), 186 
 Peniciliate (208), 74 
 Pentimerous flower (30), 38 
 Pentapanax ovary (217) 
 Pentstemon anther (132) 
 Pepo (332), 118 
 Perennial roots, 158 
 
 stems, 161 
 Perfect flowers, 31 
 Perfoliate leaf (480), 176 
 Perianth, 33 
 Periblem (420), 139 
 
 structures from, 140 
 Pericambium (421), 141 
 Pericarp defined, 105 
 
 layers of, 105 
 Perichaetium, 215 
 
 in moisses, 221 
 Pericycle (421), 141 
 Periderm, 140 
 
 secondary, 140 
 Perigone, 33 
 
 chapter on, 50 
 
 color of, 50 
 
 form of parts of, 50 
 
 number of p'iirts of, .50 
 
 special form of, 53 
 Perigynous (57, 58), 46 
 Perigyny (57, 58), 46 
 Peripheral .'nibrvn M()9, 410), 133 
 
244 
 
 INDEX 
 
 Perisperm, 12S 
 Peristome of mosses, 215 
 Perncttya flower (102) 
 Persistent, 61 
 
 leaves, 176 
 Personate (109), 57 
 Petal, parts of (18) 
 Petaloid appendage (loo), 68 
 Petals, 32 
 
 Petiolar glands, 175 
 Petiole, 26 
 
 development of, 172 
 
 forms of, 175 
 
 for climbing (569) 
 Petrocoptis seed (385) 
 Phanerogamic botany, 19 
 Phanerogams compared with crypto- 
 gams, 207 
 Pharmaceutical botany, scope of, 19, 20 
 Pharmacognosy, 20 
 Phelloderm, 140 
 Phellogen (422), 140 
 Phloem-bundles in root (422), 142 
 Phlox flower (57), 46 
 Phores, S3 
 
 Phyllanthus branch (460), 167 
 Phyllocladia (460), 167 
 Phyllodia (562), 195 
 Phyllotaxy (570-575), 196 
 
 relation to flower-structure, 199 
 Phylogeny, 18 
 Physiological botany, 18 
 Physiology defined, 18 
 Phytography, 19 
 Phytomer (1), 23 
 
 products of (1), 23 
 Picea fruit (360) 
 Pileus, 211 
 
 Piliferous layer (416), 139 
 Pilocarpus leaf (509, 525) 
 Pilose, 178 1i 
 
 Pine leaf (492) 
 Pinnae, 190 
 
 Pinnate (549, etc.), 190 
 Pinnately compound (549, etc.), 190 
 
 veined leaf (524), 186 
 Pinnatifid (538, 556), 188 
 Pinnules, 183, 190 
 Pinus pistil (174), 71 
 Piper style (181) 
 Piptoptera fruit (290) 
 Pistil, gymnospermous, 70 
 
 parts of (9, 10), 31 
 
 the, 29 
 Pistillate flower (9), 29 
 Pitcher plant (560), 192 
 Pith, 141, 146 
 Placenta (10), 32 
 Placentae, modifications of. 77 
 Plaited, 60 
 
 Plantago leaf (481, 515, 527) 
 Plantain leaf (481, 515, 527) 
 Platypodium fruit (296) 
 Plerom (420), 138 
 
 structures from, 141 
 
 Plumose anther, 68 
 
 stigma (209), 74 
 Plumule (405, 7;^, 133 
 Podophyllum rhizome (449) 
 Pollen, fixation of (275). 98 
 
 grains (14), 30 
 
 development of, 65 
 
 tube (278), 99 
 
 descent of (278), ICO 
 Polhnaria (140), 65 
 
 Pollination and fertilization, chapter on, 
 90 
 
 by birds, 93 
 
 defined, 79, 89 
 Polhnia (135, 140), 65 
 Polycarpous, 158 
 Polycotyledons (406), 133 
 Polygahneae, 219 
 Polygamous flowers, 30 
 Polygonatum rhizome (450) 
 Polygonum leaf (519) 
 Polypetalous, 53 
 Polysepalous, 53 
 Polystelar stems, 150 
 Pome (308), 119 
 Ponthiera pollinia (140) 
 Poppy fruit (358), 125 
 Pores, dehiscence by (328, etc.), 66 
 Position obscured, 42 
 Posterior side of flower, 41 
 Potaha style (186) 
 Potato (446) 
 
 Potentilla, flower of (45, 46) 
 Poterium leaf (488) 
 Praefloration (120-125), 59 
 Praefoliation, 169 
 
 Preservation of plants, chapter on, 226 
 Prickly pear (281) 
 Primary bundles of stem, 146 
 
 leaf (466) 
 
 root, 145, 158 
 
 stem, 162 
 Primine (241, etc.), 79 
 Primordial leaf (466) 
 Prismatic perigone (94), 54 
 
 style (183) 
 Procumbent stem, 165 
 Produced base (516), 184 
 Proliferation, 200 
 Propagation by cuttings, 25 
 
 by nodes (2), 25 
 
 vegetative, 25 
 Prosopis fruit (353) 
 Protection of fruit, 110 
 
 to seeds, 110 
 Proterandry (269, 270), 94 
 Proterogyny, 94 
 Protonema, 214 
 Prunus flower (58) 
 
 leaf (490) 
 Pseudima disk (260) 
 Pseudocarp, 105 
 Psorospermum (38) 
 Psyllocarpus fruit (325) 
 Pteridophyte, 215 
 
INDEX 
 
 245 
 
 PubciuU'iit , 177 
 
 Pubescent, 177 
 
 Pulsatilla flower (10, 286), 32 
 
 Pulverulent, 177 
 
 Pulviniis, 21), 173 
 
 Pumpkin, US 
 
 Punctate, 17S 
 
 Putanien, 17!* 
 
 Pyrene (331), 119 
 
 Pvrola leaf (489, 493) 
 
 Pyxis (302), 125 
 
 QuERCUS leaf (543) 
 Quinate. 191 
 
 R 
 
 Raceme (580, 582), 202 
 Rachis (5S3 and 586) 
 
 of inflorescence, 199 
 
 of leaf (475) 
 Radial section of stem (423), 147 
 Radiate, 204 
 Radicle (u in Figs. 400, etc.), 133 
 
 directions of, 133 
 Ranales, 219 
 Ranunculus akene (344) 
 
 leaf (540) 
 
 petal and nectary of (63) 
 Raphe (124. etc., 241, etc., 372. 373), SO, 
 
 130 
 Ray-flowers, 204 
 Rays (587, e), 204 
 Receptacle (587, h), 204 
 Reclining stem, 165 
 Rectinerved, 1S6 
 
 Recurved-jiendulous ovule (240), 78 
 Reduced leaves of inflorescence, 205 
 Reduplicate (121) 
 Regular iluplication, 38 
 
 suppression, 38 
 Regul^ritv, law of, 43 
 Renifonn" anther (131), 63 
 
 leaf (495), ISO 
 Repand (536), 188 
 Repent stem, 165 
 Reproduction, sexual, 29 
 Resupinate ovule (236), 78 
 Reticulate in special sense (525) 
 Reticulated leaves (524, etc.), 185 
 Retwc (512), 182 
 Reversion of tvpc, 47 
 Rcvolut c (.VIL o42).^ 89 
 Rhamnus (.T^fT 
 Riiizoids (599), Hit) 
 Rhizome compared with root, 102 
 
 forms of (147-452), 103 
 Rhizomes (447-452), 1(52 
 inionil)oi(lal (.')()()), ISl 
 ]{hytid()ma, 140 
 Ribbon-shaped leaf (4s7) 
 
 Ribs (527), 184 
 Ricinus seed (380) 
 Ring bork, 140 
 Ringent (111), 57 
 
 Root and stem structure, branching of, 
 144 
 
 cap (410), 139 
 
 diapter on, 130 
 
 hairs (410),, 139 
 
 minute structure of, 138 
 Roots and stems classified, chapter on, 
 158 
 
 duration of, 158 
 
 figures of (437-443) 
 
 forms of (441, etc.), 160 
 
 from stem, 157 
 
 functions of, 160 
 Root-structure compared with stem- 
 structure, 145 
 Rose, flower, double (59) 
 single (60) 
 
 leaf (486, 555) 
 
 sepal of (73) 
 Rosemary leaf t542) 
 Rosmarinus (542) 
 Rotate (92), 55 
 Rotund leaf (493), ISO 
 Rubus leaf (506) 
 Rugose, 178 
 
 Rules of nomenclature, 222 
 Rumex (29S) 
 
 fruit (283, 289) 
 
 leaf (522) 
 Ruminated albumin (399) 
 Runcinate (558), 192 
 Runner (445), 102 
 Rupturing fruits, 115 
 
 Saccate corolla (112) 
 Sagittate (520), 184 
 
 anther (133), 03 
 Salient teeth, 187 
 Salix, flowers of (5-13) 
 
 leaf (3, 497) 
 
 ovary di.ssection (10) 
 
 twig (1, 5-13) 
 Salpichroa (253) 
 Salverform (101, etc.), 54 
 Salvia flower (111) 
 
 stamen (104) • 
 Samara (288, etc.), 121 
 Sanguinaria anther (130) 
 San t alum disk (200) 
 Sanvcgesia seed (376) 
 Sai)onaria inflorescence (584) 
 Sap-wood, 144 
 Sarcina (.-)93), 213 
 Sarraccnia, 171 
 Sassafras anther (138) 
 
 leaf (544) 
 
 stamen (70) 
 Saucer-shaped (103), 55 
 
246 
 
 INDEX 
 
 Scabrous, 178 
 Scale-bork, 140 
 Scalv bud, 169 
 
 bulb (461), 168 
 Scape (576, a), 199 
 Scariose leaf, 177 
 Scarious leaf, 177 
 Scattered leaves, 198 
 Schizocarp (330, 334), 119 
 Scion, 25 
 Sclerotum, 210 
 Scorpioid raceme (434), 202 
 Scouring rushes, 215 
 Scurfy, 177 
 Scutellaria (151) 
 Scutellum (415) 
 Secondary growth in stem, 146 
 
 in superficial structure of root, 
 158 
 
 roots, 145 
 
 stem, 162 
 Secondaries (524, h) 
 Secund branching (434) 
 
 leaves, 155 
 Secundine (241, etc.), 79 
 Sedge leaf (465, B) 
 Sedum, flower of (47) 
 Seed, dissection and examination of, 135 
 
 appendages of (384, etc.), 131 
 
 chapter on, 127 
 
 coats, 129 
 
 figures of (369-415) 
 
 leaves, 132 
 
 method of examination of, 135 
 
 parts of, 128 
 
 \'itality of, 136 
 Seeds, provisions for scattering, 113 
 Seedless plants, 207 
 Sepals, 32 
 Septa, 32 
 
 abortion of (230), 76, 106 
 
 development of new, 106 
 
 of fruit, abortion of, 106 
 Septate, 191 
 
 Septicidal dehiscence (316) 
 Sericeous, 177 
 Series of plants, 219 
 Serrate (533), 187 
 Serrulate (535), 187 
 Sessile leaf (478) 
 Sexual reproduction, 29 
 Sheathing leaf (162) 
 Shrub defined, 165 
 Siccose, 116 
 Sickle-shaped, 182 
 Sicyos anther (139) 
 Sidalcea (149) 
 Sieve bundles in root (422), 142 
 
 tissue, 142 
 
 tubes (422), 142 
 Sigmoid calyx (106), 56 
 Silene, vertical section of flower (72) 
 Silicic (353-357., 121. 125 
 Silique (254), 125 
 Simple fruit, 105 
 
 Simple pistil (219, etc.), 71 
 
 stems, 164 
 Sinapis, androecium of (33) 
 Single and double flowers (59, 60) 
 Sinistrorse (124), 60 
 Sinuate (536), 53, 188 
 
 disk (263) 
 
 perigone (91) 
 Sinuous anther (139), 64 
 Sinus, 32 
 
 Siphocampylos fruit (328) 
 Skunk cabbage inflorescence (585) 
 Sleeping and awakening of flowers, 93 
 Smilax leaf and tendril (565), 167 
 Solanum (92), 220 
 Solidago leaf (478, 496, 502) 
 Sohd bulb, 168 
 Sophora fruit (352), 124 
 Sori, 217 
 
 Spadix (585, 586), 202 
 Spathe (585), 205 
 Spathyema inflorescence (585) 
 Spatulate (503), 181 
 Species of plants, number of, 219 
 Specific name, 222 
 Spermatophyta, 219 
 Spigelia (97) 
 Spike (583), 202 
 Spikelet (347, 589), 123, 206 
 Spines (453), 165 
 
 becoming branches (454) 
 Spinulose teeth, 188 
 Spiral leaf arrangement (571), 190 
 Sporangium, 30 
 Spore germination in cryptogams, 101 
 
 mother cells, 65 
 Sporophyll, 30 
 Sporophyte, 30 
 Spur (65), 58 
 Squash androecium (148) 
 Staeha fruit (326) 
 Stamen-circle, the single, 43 
 
 column, 46, 66 
 
 parts of (12, 14), 31 
 Staminate flower (12), 30 
 Staminodia (38, 44), 62 
 Standard (110), 57 
 Stele, 141 
 
 differentiation of its cells (421) 
 
 secondarv growth in, 142 
 Stellaria flower (39, 40) 
 Stem and root structure, chapter on, 136 
 
 composition of, 26 
 
 extensions and appendages of, chap- 
 ter on, 153 
 
 structure compared with root struc- 
 ture, 145 
 nionocotyledonous (424) 
 Stems and roots classified, chapter on, 
 158 
 
 classification of, 161 
 
 duration of, 161 
 
 order of development, 162 
 
 subterranean (444-452), 162 
 Sterile filament on anther, 62 
 
INDEX 
 
 247 
 
 Stigma, forms of (191-215), 7.S 
 
 papillose (275), 97 
 
 position of (191-215), IS 
 
 size of, proportional to number of 
 ovules, 73 
 Sligmatophyllon (206) 
 Stipellae (475), 175 
 Stipulate leaves (474, 475), 174 
 Stipule, 26 
 Stipules, development of (471), 171 
 
 forms of, 173 
 Stolon, 162 
 Stone-fruit, 118 
 Storage roots (441-443), 160 
 
 stems, 168 
 Stramonium leaf (5231 
 
 seed (379) 
 Strap-shaped (104), 55 
 Strawberry (304) 
 
 calyx (36) 
 
 plant (445) 
 Strigose, 178 
 Strobile ^360, 361), 126 
 Strophanthus seed (388) 
 Strophiole (374), 130 
 Structural botany, 18 
 
 units, modifications of, 26 
 Strychnos tendril (4551 
 Style (9), 32 
 
 forms of, 72 
 
 position of (177, etc.), 72 
 Subgenera, 219 
 
 families, 219 
 
 petiolar bud, 157 
 Subterranean roots, 160 
 
 stems, 162 
 Subulate (499), 181 
 
 style (188) 
 Succirubra bark (426) 
 Succowia (357) 
 Succulent leaf (169) 
 Sucker, 162 
 Sucking disk (459) 
 Suffruticose stem, 165 
 Superior calyx (56), 45 
 
 side of flower, 41 
 Supernumerary bud, 169 
 Suppression, 38 
 Supra-axillary bud, 169 
 Suspended ovules (235, 237), 78 
 Surfaces of leaf classified, 177 
 Suture of anther, 65 
 Sword-shaped leaf (504) 
 Syconium (362), 125 
 Symbiosis, 213 
 Symmeria ovule (233) 
 Symmetrical Hower defined, 37 
 Sympodial stems (428-132), 154 
 Synandrium. 66 
 Svncarpous fruit, 105 
 
 pistil (218, etc.), 70 
 Syngenesis, 38, 44 
 Synpetalous, .")3 
 Synsepalous, 53 
 Systematic botany, 18 
 
 Tabkrn.xemont.vna anther (133) 
 Tail (115), 58 
 Taka-diastase, 210 
 Tamarind, 119 
 
 origin of pulp (317) 
 Tanacetuni, ak^ne of (75) 
 Tangential section of stem (423), 147 
 Tapering (514), 183 
 Tap-root (439), 158 
 Taraxacum floret (41, 104) 
 
 leaf (558) 
 Taxus pistil (175) 
 Tegmcn, 129, 131 
 Tendril of grape, origin of (431) 
 Tendrils from branches (455), 160 
 Teratology, 47 
 Terete, 64 
 Ternate 191 
 Tertiaries (524, c) 
 Testa (376, etc.), 129, 130 
 Tetrad, 65 
 
 Tetrad vnamous (33), 67 
 Tetramerous flower (29), 38 
 Tetraplasandra ovary (218) 
 Thalamiflorae, 219 
 Thalamus, 33 
 Thallophyta, 210 
 Theca (14), 31 
 Thecaphore (9), 31 
 Theobroma, petal of (71), 38 
 Theoretical formulae, 40 
 Thorns, 165 
 
 Thread-shaped leaf (491), 179 
 Throat of perigone (94), 54 
 Thvrse, 203 
 
 Tig'er lily bulblets (464), 168 
 Tilia flower (34, 37) 
 Tissue development, 136 
 Tobacco seed (378) 
 Tococa leaf (568) 
 Tomato, 118 
 
 anther (142) 
 Tomentellate, 178 
 l'(jinentosc, 178 
 Toothed perigone (102) 
 Torsion (49-53), 42 
 Torus, chapter on, 82 
 
 the (16, 23, 24), 33 
 Transportation of fruit, 107 
 Transverse section of stem (423), 147 
 Trape/.oidal, 181 
 Tree defined, 165 
 Tribes, 219 
 Triadelphous, 66 
 Trichomes, 156 
 Trifoliolatc (548). 191 
 Trifolium leaf (548) 
 Trijugate, 192 
 1'rimerous flower (28), 3S 
 Trimorphism, 96 
 Trinomials, 223 
 Tri-j)innate (5.56). 192 
 
 ternate, 192 
 
248 
 
 INDEX 
 
 Trumpet-shaped, 54 
 Truncate, 182 
 
 stigma (197), 74 
 Tube of perigone (94), 54 
 Tubercles (437), IGO 
 Tubers (440), 161 
 T-ufted leaves, 198 
 Tulip (576) 
 
 Tunicated bulb (462), 168 
 Twining stem, 165 
 Two-lipped corolla (111) 
 Two-senallod ovules (219) 
 Typical flower and modifications, 36 
 
 ULMTJsleaf (511, 531) 
 Umbel (579;, 202 
 Umbellule, 203 
 Unicellular plants, 208 
 Undershrub, 165 
 Undulate (537), 53, 188 
 
 perigone (91) 
 Unequal leaf (505) 
 Unequally pinnate (555), 192 
 Unguiculate, 33 
 Unguis (18), 33 
 Unifoliolate leaf (551), 190 
 Upper lip (111) 
 Urceolate (102), 54 
 Urena (330) 
 Urn-shaped (102), 54 
 Utricle (341), 121 
 
 VAcriNiUM, ovary of (222) 
 
 Valerian fruit (293) 
 
 Valvate (123), 59 
 
 Valves of fruit. 113 
 
 Valvular dehiscence (138), 66 
 
 Vanilla flower (54) 
 
 Varietal name, 224 
 
 Varieties, 220 
 
 Vegetable sulphur, 216 
 
 Veinlets, 184 
 
 Veins, 184 
 
 Venation. 184 
 
 Venus's fly-trap (561), 193 
 
 Ventral dehiscence (142), 65 
 
 Ventricose corolla (111), 56 
 
 Veratrum flower (28) 
 
 Verbascum leaf 1,477) 
 
 Verbesina fruit (295) 
 
 Vernation, 169 
 
 Vernonia floret (271) 
 
 Versatile anther (129), 63 
 
 Vertical extension by branches (431) 
 
 Verticil, 196 
 
 Verticillate, 196 ^/ ^ 
 
 141 
 
 Vexillum (110), 57 
 Viburnum inflorescence (268) 
 
 leaf (534, 535) 
 Villaresia ovary (177) 
 Viola anther (171) 
 
 pedata leaf (553) 
 Violet leaf (519) 
 Virgin's bower leaf (569) 
 Viscaria (248) 
 Vitality of seeds, 136 
 Vittae (335, a), 120 
 
 W 
 
 Watermelon, origin of pulp (312) 
 Water lily, metamorphosis in (62) 
 Wedge-shaped (518), 184 
 Wheel-shaped (92), 55 
 White oak leaf (518) 
 Whorl, 196 
 Whorled leaves, 196 
 Wild-cherry leaf (490) 
 Willow cone (5), 27 
 
 flowers of (5-13) 
 
 leaf (3, 497) 
 
 ovary dissection (40) 
 
 twig (1, .5-13) 
 Wind-transportation of fruit (287, etc.), 
 
 98 
 Winged petiole, 175 
 Wings (110), 57 
 Winter annuals, 158 
 
 bud, 161 
 Witch hazel leaf (505) 
 Wood-bundles in root (422), 142 
 
 fibers, 142 
 Woody roots, 160 
 Wyethia, akene of (77) 
 
 Xanthium, 122 
 
 Xanthoceras disk (264) 
 
 Xerophytic, 194 
 
 Xylem bundles in root (422), 142 
 
 Yeast plant, 210 
 Yew pistil (175) 
 
 Zea style (190) 
 Zinnia fruit (291) 
 
 60 
 
 
T"^ / N. MANCHESTER. 
 
 INDIANA