BIOLOG1

THE LIBRARY

OF

THE UNIVERSITY OF CALIFORNIA

GIFT OF

Mrs. William H. Harrison

APPLETONS' SCIENCE TEXT-BOOKS.

DESCRIPTIVE BOTANY,

APPLETONS' SCIENCE TEXT-BOOKS.

The following works of this new series will be im- mediately issued ; others are to follow :

The Elements of Chemistry.

BY PROF. F. W. CLARKE,

Chemist of the United States Geological Survey.

The Essentials of Anatomy, Physiology, and Hygiene.

BY ROGER S. TRACY, M. D.,

Author of " Handbook of Sanitary Information for Householders," Sanitary Inspector of the New York City Health Department,

A Compend of Geology.

BY JOSEPH LE CONTE,

Professor of Geology and Natural History in the University of California ; author of " Elements of Geology," etc.

Elements of Zoology.

BY C. F. HOLDER,

Fellow of the New York Academy of Sciences, Corresponding Member of the Linnsean Society, etc. ;

AND J. B. HOLDER, M. D.,

Curator of Zoology of American Museum of Natural History, Central Park, New York.

Descriptive Botany.

BY ELIZA A. YOUMANS.

' Science fct-0ohs.

DESCRIPTIVE BOTANY,

A PRACTICAL GUIDE

TO THE CLASSIFICATION OF PLANTS, WITH A POPULAR FLORA.

BY

ELIZA A. YOUMANS,

AUTHOR OF " THE FIRST BOOK OF BOTANY " ; EDITOR OF " HENSLOW's BOTANICAL CHARTS."

NEW YORK: D. APPLETON AND COMPANY,

I, 3, AND 5 BOND STREET. 1889.

mm;

COPYRIGHT, 1885, BY D. APPLETON AND COMPANY.

CONTENTS.

PAGB

INTRODUCTION ix

DIRECTIONS FOR STUDY xix

AN EXPLANATION OF THE ABBREVIATIONS USED IN THE BO- TANICAL CHARTS xxv

CHAPTER FIRST. -THE LEAF.

EXERCISE

I. The Parts of Leaves I

II. Venation 2

III. Leaf-Margins 4

IV. The Figures of Leaves 9

V. Compound Leaves 12

VI. Varieties of Compound Leaves 13

CHAPTER SECOND.— ROOTS AND STEMS.

VII. Roots • . . . 18

VIII. Stems and their Parts 21

IX. Buds 21

X. Stem and Leaves 23

XI. Kinds of Stems 25

CHAPTER THIRD.— THE INFLORESCENCE AND FLOWER.

XII. Kinds of Inflorescence 29

XIII. The Parts of Flowers . . . 32

XIV. Stamens and Pistil 34

XV. Kinds of Calyx and Corolla 36

XVI. Kinds of Corolla 38

XVII. Symmetry of Flowers . 43

XVIII. Complete and Incomplete Flowers 44

253

VI

CONTENTS.

EXERCISE PAGE

XIX. Form of the Receptacle and Insertion of Floral Organs 47

XX. Polyandrous Stamens 48

XXI. The Growing together of Stamens . . . .50

XXII. The Growing together of Carpels . . . -52

XXIII. Union of Floral Whorls with each other — Calyx and

Pistil 58

XXIV. The Union of Floral Whorls with each other— Corolla 60 XXV. Union of Floral Whorls with each other — Stamens . 61

XXVI. The Receptacle 67

XXVII. Appendages of the Receptacle 69

CHAPTER FOURTH.— COMPARING AND CLASSIFYING PLANTS.

XXVIII. Plant Characters and Affinities XXIX. How to begin Classification

72 76

CHAPTER FIFTH.— THE MINUTE STUDY OF THE ESSENTIAL ORGANS OF PLANTS.

XXX. Parts of Stamens

XXXI. Number and Shape of Anther-Lobes

XXXII. Dehiscence of the Anther .

XXXIII. Introrse and Extrorse Anthers .

' XXXIV. Attachment of Filament to Anther

XXXV. Forms of Filaments

XXXVI. Structure and Forms of Pollen .

XXXVII. Forms of Connective .

XXXVIII. General Features of Stamens

81

82 83 84

85 87 88

89 90

CHAPTER SIXTH.— THE PISTIL.

XXXIX. Kinds of Style and Stigma .

XL. Form and Position of Styles

XLI. Pistil, Ovary, Fruit

XLII. The Structure of Ovaries .

XLIII. Placentation

XLIV. Modes of Dehiscence . . - .

XLV. Direction of Ovules and Seeds .

XLVI. Parts of the Ovule . .

XLVII. Kinds of Ovule ... . . .

XLVIII. The Composition of Fruit . .

92

93

93

95

98

101

103

104

105 106

CONTENTS. vii

EXERCISE PAGE

XLIX. Parts of the Pericarp 108

L. The Classification of Fruit 109

LI. The Seed.— Its Form and Structure . . . .114

LII. Parts of the Seed 115

LIII. Parts of the Body, or Kernel 117

LIV. Parts of the Embryo 119

LV. Monocotyledons and Dicotyledons . . . .121

LVI. Position of the Embryo in Seeds . . . . . 122

CHAPTER SEVENTH.— FLORAL SYMMETRY, PHYLLO- TAXY, PREFLORATION, CYMOSE INFLORESCENCE.

LVI I. Numerical Plan of Flowers . . ' . . . .124

LVIII. Alternation of Parts in Flowers 125

LIX. Leaf- Arrangement. — Phyllotaxis 126

LX. Arrangement of Floral Leaves in the Bud. — Estivation,

or Prefloration 132

LXI. Cymose or Definite Inflorescence 135

CHAPTER EIGHTH.— THE COMPOSITE.

LXII. Parts of Flower-Heads 139

LXI II. The Florets 142

LXIV. Characters of the Composite 146

CHAPTER NINTH.— THE CRUCIFERE. LXV. Characters of the Cruciferae 149

CHAPTER TENTH.— THE UMBELLIFERE.

LXVI. Structure of the Flowers and Fruit . . . .151 LXVII. Classification of Umbel-bearing Plants . . . .154

CHAPTER ELEVENTH.— THE LABIATE. LXVII I. Characters of the Labiatse 157

CHAPTER TWELFTH.-THE CONIFERE. LXIX. Characters of the Conifers ..... 161

viii CONTENTS.

EXERCISE PAGE'

CHAPTER THIRTEENTH.— THE ORCHIDACE.E. LXX. Characters of the Orchidacecc . . . . 167

CHAPTER FOURTEENTH.— THE GRAMINE^E. LXXI. Characters of the Gramineae 171

CHAPTER FIFTEENTH.— FLOWERLESS PLANTS.

L.XXII. Ferns 176

LXXIII. Reproduction of Ferns 177

LXXIV. Mosses . . . . ' . . . • . .180 LXXV. Fungi . . . . ' . '. ' . . .182

LXXVI. SYSTEMATIC BOTANY 185

INTRODUCTION.

THE " First Book of Botany," published in 1870, was prepared as a contribution to better methods in object- teaching. It was not designed as a text-book of Botany ; but plants were chosen as objects of study, because they offer special and unequaled advantages for training in ob- servation. It provided that the whole work of the learner should be upon his specimens; that he should find out and record the plant-characters for himself, and thus get im- portant practice in self-education.

But it was soon seen that, in thus cultivating the ob- serving powers, we were laying the true foundation for a jeal knowledge of Botanical Science ; and the desire was often expressed that this method of studying plants should be carried out more fully. Accordingly, the " Second Book of Botany" was prepared upon the same plan. It has, however, been found desirable, for the sake of beginners in the science who are too old for primary lessons, that the abridged contents of the " First Book " should be pre- fixed to the " Second Book," and also that completeness as a Descriptive Botany should be given to the work, by adding to it a popular Flora. In thus combining the exer- cises of the former volumes, they have not been materially changed. They provide for the direct study of all those features of plants which are used in classification, and illustrate by practical examples the use to be made of these observations in systematic botany. The ideas given in those works, concerning the value of this study in men- tal training, are therefore equally applicable here.

x INTRODUCTION.

By the common practice of the schools, pupils often " go through " the botanical text-books with only the most incidental attention to the real objects of study. As there is no training in observation, there can be no attempt at the exercise of the reason and judgment of the learner upon the results of observation. To attain this important end, botany must be studied in its actual objects. The characters of plants must become familiarly known by the detailed and repeated examination and accurate descrip- tion of large numbers of plants. The pupil must proceed step by step in this preliminary work — digesting his ob- servations, and making the facts his own. From the be- ginning he will be engaged in comparing his observations, and reasoning upon his facts. As he extends his knowl- edge, the work of comparison and grouping calls for a higher exercise of thought. In the final classification of plants, problems of increasing complexity arise. Plants are to be placed in groups subordinate to each other, when judged by masses of resemblances, by likenesses, and differences of unequal values, which involve the exer- cise of the best powers of the mind.

That the habit of systematic arrangement, in which the study of botanical classification affords so admirable a training, is equally valuable in methodizing all the re- sults of thought, is testified to as a result of his own expe- rience by that eminent authority, Mr. John Stuart Mill. He was a regular field botanist, and cultivated the subject with a view to its important mental advantages. In the second volume of his " System of Logic "Mr. Mill says :

" Although the scientific arrangements of organic na- ture afford as yet the only complete example of the true principles of rational classification, whether as to the formation of groups or of series, these principles are ap- plicable to all cases in which mankind are called upon to bring the various parts of any extensive subject into men- tal co-ordination. They are as much to the point when

INTRODUCTION. xi

objects are to be classed for purposes of art or business, as for those of science. The proper arrangement, for example, of a code of laws, depends on the same scientific conditions as the classifications in natural history ; nor could there be a better preparatory discipline for that im- portant function than the study of the principles of a natural arrangement, not only in the abstract, but in their actual application to the class of phenomena for which they were first elaborated, and which are still the best school for learning their use."

But it will be a grave mistake to suppose that these benefits can be secured by the mere use of text-books, however full and valuable the information they contain. Nor are they to be gained by the casual examination of plants, nor by the analyses of a few flowers, with the aid of keys and dictionaries, nor in the limited time usually allotted to the subject. The study must be commenced early, and pursued steadily by direct observation, until its elementary facts and principles are made familiar. It is the claim of this book that, if its method is faithfully fol- lowed, it will not only secure an actual acquaintance with an important branch of knowledge, but will enforce a mental discipline of much value in the intellectual work of life, and which is greatly needed in general education.

The exercises of the volume are designed simply as guides to self-education. The pupil is told very little. From the beginning to the end he is sent to the plant to get his knowledge of the plant. The science of botany is especially available for self- culture, because its element- ary facts are so simple that their study can be commenced in early childhood, and so numerous as to sustain a pro- longed course of observation. From rudimentary and simple facts the pupil may proceed gradually to the more complex ; from observation to the truths resting upon observation, through a course of successively higher and more comprehensive exercises. Under the guidance here

xii INTRODUCTION.

afforded, the pupil begins his study with leaves, the least complex in structure of the organs of plants, and learns to distinguish all their external characters. At the same time he learns the precise terms by which their parts and features are denoted, and these terms become familiar by use in his written descriptions.

If, in looking over the following pages, objection should be made to so many technical terms, the reply must be that without them it is impossible to gain the mental bene- fits of this method of study. The learning of words is a large part of education, but learned in the usual loose way they favor lax and careless habits of thought. To coun- teract this and give clearness to the mental operations re- quires a discipline adapted to the purpose. Vagueness in the meaning of words necessarily involves vagueness of thought and expression ; while to have clear ideas and be able to clothe them in correct language, it is necessary to know precisely what the words represent. This end can only be secured in the best manner by the objective meth- od, in which the mind is directed first to the observed facts, the specific characters, or the definite relations, so that the terms applied to them acquire fixed and accurate meanings. Careful and minute observations recorded in explicit terms make clearness of thinking and precision of language a habit of the mind. To secure this important object, descriptive botany is superior to any other study. Its terms have been slowly perfected, and are much the same in all languages. The vocabulary of botany is more copious, precise, and well-settled than that of any other natural science, and it is therefore unrivaled in the scope it affords for exercise in clear and accurate thinking, and for the best cultivation of the descriptive powers.

The method of instruction developed in these pages was devised and carried into most successful practice by the Rev. J. S. Hen slow, Professor of Botany in Cambridge University, England. He had a parish at Hitchin, and

INTRODUCTION. xiii

resolved to try what might be done in teaching botany to the country children of the village school. His experi- ments were most interesting, and their results, which are of great value in education, were made public by Dr. J. D. Hooker, Superintendent of the Botanical Gardens at Kew, in evidence that he gave upon the subject before a parlia- mentary commission.

The following passages from his testimony will give an idea of Prof. Henslow's method :

Question. Have you ever turned your attention to the teaching of botany to boys in classes at school ?

Answer. I have thought it might be done very easily. My ideas are drawn from the experience of my father-in- law, the late Prof. Henslow. He introduced the study of plants into the village school of his parish. His system was entirely voluntary. He enrolled the children in a class, and left them to collect plants for themselves ; but he visited his parish daily, when the children used to come up and bring the plants they had collected, so that the lessons went on all the week round.

Q. Do you know in what way he taught it ? Did he illustrate it ?

A. Invariably; he made it practical. He made it an objective study. The children were taught to know the plants, and to pull them to pieces ; to give their proper names to the parts; to indicate the relations of the parts to one another ; and to find out the relation of one plant to another by the knowledge thus obtained. They learned it readily and voluntarily, and were extremely interested in it and fond of it.

Q. Do you happen to know whether Prof. Henslow thought that the study of botany developed the faculties of the mind — that it taught these children to think ? And do you know whether he perceived any improvement in their mental faculties from that ?

A. Yes ; he used to think it was the most important

xiv INTRODUCTION.

agent that could be employed for cultivating their facul- ties of observation, and for strengthening their reasoning powers.

Q. And Prof. Henslow thought that their minds were more developed ; that they were becoming more reasoning beings, from having this study superadded to the others ?

A. Most decidedly. It was also the opinion of some of the inspectors of schools, who came to visit him, that such children were in general more intelligent than those of other parishes ; and they attribute the difference to their observant and reasoning faculties being thus devel- oped. . . .

Q. So that the intellectual success of this objective study was beyond question ?

A. Beyond question. ... In conducting the examina- tions of medical men for the army, which I have now con- ducted for several years, and those for the East India Company's service, which I have conducted for, I think, seven years, the questions which I am in the habit of put- ting, and which are not answered by the majority of the candidates, are what would have been answered by the children in Prof. Henslow's village school. I believe the chief reason to be, that these students' observing faculties, as children, had never been trained— such faculties having lain dormant with those who naturally possessed them in a high degree ; and having never been developed, by train- ing, in those who possessed them in a low degree.

It thus appears that Prof. Henslow left his pupils mostly to themselves, meeting them occasionally to con- sult with them, and advise them when in doubt or diffi- culty. But he did not rely alone upon the fascination of the subject to secure his purpose.

His profound knowledge of the science and his wis- dom as a teacher enabled him to devise and skillfully ar- range a series of questions, calling attention to all the points of scientific interest in the structure of flowers, and

INTRODUCTION. Xy

the answers to which would in each case disclose the im- portant characters of the plant described. The pupils were supplied with copies of these questions — schedules, as he called them — and answers were found to them by ex- amining living plants. When a plant had been described in writing by answering these questions, its schedule was pinned fast to it, and it was the examination of the col- lective work of a scholar, whether by the professor or by a more advanced fellow-learner, that took the place of for- mal recitation. Left in this way to be his own teacher, and do his own thinking, the method is seen to be chiefly one of self-education.

Prof. Henslow prepared no elementary book upon bot- any carrying out his method : the printed schedule he used applied only to the flower, the most complex part of the plant, and the attention of children was directed by it chiefly to those features upon which orders depend in classification. But, instead of confining the use of sched- ules to the study of the flower, I have employed them throughout the work. In the first three chapters, the pupil is provided with leaf, stem, inflorescence, and flower- schedules on which, guided by the questions, he writes down the results of his observations. All the organs of the plant, and all their important modifications, are stud- ied in this way. The presence or absence of botanical features that determine their place and rank among plants is first noted ; and, when found, they are accurately and concisely described.

In Chapter IV the subject of classing plants accord- ing to their natural affinities is entered upon. From the beginning of his schedule-work the pupil has really been classing plants in a limited way and without being aware of it. But he is now led to discover that he has been all the while using the principle on which the natural method of classification is based, and that the mastery of Prof. Henslow's flower-schedule has made the grouping of

xvi INTRODUCTION.

plants by this method both intelligible and easy. When he has answered all its questions concerning any plant, he has possession of the facts upon which its true classifica- tion depends.

The next three chapters of the book are devoted to the observation of those minute but especially important characters of plants which require the constant use of magnifying - glasses in their study. Practice with the flower-schedule in describing newly-discovered plants, and in a more searching study of familiar ones, is still con- tinued, and furnishes inexhaustible interest to the learner.

The remaining chapters of this volume are accordingly given to a critical study of six of the most natural orders of plants, specimens of which everywhere abound ; and the principles of classification illustrated by these groups will prepare the pupil for a rational use of the Flora, and thereby enable him to dispense with the artificial key that usually accompanies a popular Flora.

I have, said that by the common method of studying botany there is no training in observation. The text- book is read and recited in the customary class-room way; and there is only the most incidental attention to the liv- ing objects of study, and no attempt to exercise the pupil's own faculties in solving the questions they offer. Accord- ingly, when classification is attempted, an artificial key has to be resorted to, which takes the place of the actual knowledge which the learner should have. It is at this stage that the contrast in results of the two methods is most apparent. When, by following the key, a pupil seeks for the class, order, genus, etc., to which the plant in hand belongs, he does not use his own knowledge. The struct- ure of the plant is to be compared with an ideal ; but he has not the ideal, neither can he interpret structure. So he turns to the key and learns what to look for first. When he has found the part specified, he compares its appearance with the statement of the key. If this seems

INTRODUCTION. xvii

to agree with the structure under examination, he is di- rected what to look for next; and if there is no agree- ment, he is told what to do. The same process is repeat- ed over and over again to the end, with very little mental benefit. The key is simply an elaborate substitution of blind groping for the intelligent action of the pupil's own faculties. The scholar undertakes that for which he has had no preparation and which is beyond his ability ; and in most cases he is too worried and confused by this unintelligible process to be able, when he sees another plant of similar structure, to recognize it. The law that time is needed for the accumulation and orderly assimila- tion of observations and the acquirement of clear ideas has been neglected, and so all his after- work in descriptive botany is wasted. By the present method, however, while the pupil is studying the structure of plants, his reflective faculties are all the while taxed to decide concerning their relationships. And when all those plant-characters upon which science insists have become familiar, so that the eye at once seizes upon them, the exercise of judgment in de- termining the groups to which a plant belongs is spontane- ous and inevitable.

The popular Flora contained in this work will serve as a thorough preparation for the use of complete manuals. It will acquaint the pupil with the leading orders and genera of plants, and with those representative species having the widest range, which are found everywhere, and will most help the learner in mastering the principles of classification. It has been prepared under the immediate supervision of Dr. Byron D. Halsted, Professor of Botany in the Agricultural College of Ames, Iowa, whose extended and thorough knowledge of the science is an assurance that the work is accurate and in accordance with the most advanced views of systematic botany.

While the portion of botany to which this volume is devoted can not be learned from books, there is another

xviii INTRODUCTION.

part of this extensive science that may be more success- fully pursued by ordinary school methods of instruction. This is physiological botany. By means of diagrams and the explanations of the text, the scholar is enabled to per- ceive how and of what the parts of plants are built up, and what functions these parts perform in its history as a living being. A valuable manual on this branch of botany by an eminent authority will shortly appear in this series, which will complete the exposition of the science here begun.

DIRECTIONS FOR STUDY.

THE first three chapters of this book were prepared for young children, and are, therefore, very simple and rudi- mentary. But the course of observations they contain are not to be dispensed with by beginners of any age. The constant temptation of older pupils will be toward haste and inadequate observation. The danger is that plants enough will not be collected, and that the parts of such as are collected will not be studied with sufficient care. The influence of the teacher will therefore be con- stantly needed to check the too rapid passage of older pu- pils over that portion of botany included in these chapters.

An excellent way to familiarize pupils with these plant- characters is for them at once to set about preserving and describing specimens of all the- varieties they collect.

As good an arrangement as any for pressing plants consists of two stout boards, that will not warp or bend, between which the specimens are placed, with any con- venient weight — as stones, or masses of iron, of not less than fifty or sixty pounds — laid on the top. Between the plants you put layers of drying-paper. Newspapers an- swer very well for this purpose. They should be made into packets of about a dozen thicknesses, stitched togeth- er. Lay the specimens smoothly between these packets, having fastened to each of them as full a description as your studies enable you to write. Put unsized paper be- tween the parts of a specimen that overlap each other, to prevent molding and hasten drying. Be careful to dispose the plants so that they will not lie directly above each other; keep the top of the pile as level as possible, to

xx DIRECTIONS FOR STUDY.

equalize the pressure. The number of packets interposed will depend upon the juiciness of the plants, and must be left to your own judgment. When plants are first put in press, the papers should be changed once a day for three or four days, after which every other day will answer. When the drying packets are changed, they should not be left lying upon the floor, but should be dried upon a line stretched across the room, or in the open air.

At each change of the driers, any further knowledge that has been gained concerning each specimen should be written down, and preserved with it as before. In this way all its features will be observed, and the names denoting them recalled, and by the time they are dried for mount- ing, it will be possible, by the aid of the last schedule of the chapter, to write, upon the paper holding the speci- men, an accurate scientific description of it. Let this be followed by the pressing of entire plants, after compar- ing their different organs with the examples shown in the book. The attention thus drawn to their characters will be kept alive in changing them and caring for them, and the attempt completely to describe them, when dried and mounted, will go far toward fixing in the mind ideas of the forms and structures of the various organs, and the

terms needed in description. For collecting plants, you wrill need a small trowel for digging roots, or a large, strong clasp-knife, that will serve both for digging and for cutting branches ; a strong portfolio, from sixteen to twenty inches long, and ten

FIG. A. -Collector's Portfolio. or twelve inches wide, tied

with tape or a strong cord.

It should be made of two stout sheets of pasteboard, sepa- rated at the back (Fig. A), and will be all the better if cov-

*

DIRECTIONS FOR STUDY.

xxi

ered with enameled cloth, to protect it from moisture. This portfolio should contain a stock of thin, unsized paper, such as the poorest printing-paper, or grocer's tea-paper. It is often convenient to have a close tin box, for preserv- ing specimens, to be examined at home while fresh. Such a box, or vasculum, is shown strapped upon the collector in Fig. B. It shuts close, and has two compartments: the large one, with a door in the side, nearly as long as the box ; and a small one, two or three inches deep, with a door in the end, for receiving- small, delicate specimens of any kind.

If the collector wishes to prepare

an herbarium, his specimens must be gathered with great care, and pains must be taken to get average examples of each species. If possible, they should be gathered in dry weather. Herbs should be gathered when in flower and in fruit. They should be taken by the root, and, if it is not too large, this should be pressed, along with the rest, to show whether the plant is annual, biennial, or perennial. Thick roots, bulbs, tubers, and the like, should be thinned with a knife, or cut in slices, lengthwise. Buds and fruit should be obtained, as well as the expanded flower. All three may sometimes be found upon the same plant, but generally they will have to be obtained at different times, unless, in- deed, you are able to find buds, flowers, and fruit, all at once, upon plants in different stages of development.

FIG. B.— A Collector at Work.

xxii DIRECTIONS FOR STUDY.

Small herbs may be preserved entire. If the radicle leaves are withered at flowering-time, get a younger speci- men in which they are fresh. When herbs are too large for this, they may be cut in sections, or folded, or you must be content with branches and specimen-leaves taken from near the root. In the case of woody plants, one or more shoots should be taken, bearing leaves, flowers, and fruit. Both sterile and fertile flowers should be obtained from monoecious and dioecious plants.

The specimens, when freshly gathered, should be laid between the sheets of the portfolio, the more delicate ones being carefully placed between sheets of drying-paper, so that, on reaching home, they can be transferred to the press without being disturbed. The folds and doublings of leaves and petals of ordinary plants, occasioned by the wind, in the open field, are easily smoothed out when putting the plants in press.

MOUNTING OF SPECIMENS. — When the plants are dry, the next thing is to mount them. For this purpose you will need — i. Strong, heavy, white paper, larger than fools- cap ; sheets 17^- inches in length byii^ inches in width is a size, on many accounts, desirable. 2. Corrosive sub- limate, for poisoning plants, to keep off insects. 3. Glue, to fasten them upon the paper.

Dissolve about an ounce of sublimate in a quart of alcohol. It should be labeled, and kept with great care, as it is very poisonous. A simple way of applying the solution is to pour a little into a large, flat platter, so as to cover the bottom, and " immerse the whole specimen for a second therein." After poisoning, the specimens are to be laid between driers, and subjected to slight pressure for twenty-four hours, when they are ready to be fastened to the paper. The flowers and tender parts of coarse, tough plants are all that need poisoning.

The specimens are to be fastened to the paper with hot glue, about as thick as cream, laid on to the plants

DIRECTIONS FOR STUDY. xxiii

with a camel's-hair pencil. Strips of thin, gummed paper should then be fastened over the thicker parts, to' prevent their coming loose in handling. Prepare your glue in an earthen or porcelain-lined vessel, as corrosive sublimate acts on all common metals, and the brush, passing from plant to glue again and again, will be likely to produce stains if there is a trace of metal in the solution.

The labeling and arranging of plants depend upon their classification. When you know the characters upon which classes are founded, have begun to consider the affinities of plants, and have studied a few natural orders, you may intelligently begin to arrange your plants in their proper order. But, before attempting this, you should be so familiar with the assemblages of characters that plants present, and with their relations to each other, that you at once see why a plant is placed here and not there in your collection. In the Flora you will find a full statement of the characters of each order, followed by those of its lead- ing genera, and of such representative species as will aid in the full comprehension of the principles involved.

THE USE OF CHARTS. — Many of the features of plants are so minute that they are at first difficult to find, and much is gained by consulting beforehand enlarged and colored diagrams showing the botanical characters of the various organs of plants. " Henslow's Botanical Dia- grams," published by the Science and Art Department of the English Educational Council, have a high reputation for their scientific accuracy, their completeness of illustra- tion, their judicious selection of typical specimens, and their skillful arrangement for purposes of education. Wish- ing to furnish pupils with every advantage in this study, the author induced her publishers to incur the very con- siderable expense of publishing a revised and enlarged American edition of the English Charts. In place of the nine English sheets, this set consists of six large charts in which several American plants have been substituted for

xxiv DIRECTIONS FOR STUDY.

species that do not occur in this country, and illustrations of the classes of flowerless plants have been added for which Prof. Henslow did not find room.

In the plan of the charts, the plant is first represented of its natural size and colors ; then a magnified section of one of its flowers is given, showing the relations of the parts to each other. Separate magnified views of the different floral organs, exhibiting all the botanical charac- ters that belong to the group of which it is a type, are also represented. The charts contain nearly five hundred fig- ures colored to the life, and which represent twenty-four orders and more than forty species of plants, showing a great variety of forms and structures of leaf, stem, root, inflorescence, flower, fruit, and seed, with numerous in- cidental characters peculiar to limited groups. All these are so presented as to be readily compared and contrasted with each other.

The charts are not designed to supersede the study of plants, but only to facilitate it. Their office is the same as the illustrations of the book ; but they are more perfect, and bring the pupil a step nearer to the objects themselves.

Besides this special assistance in object-study, the charts will be of great value in illustrating the Flora. In fact, they are designed to present, fully and clearly, those groupings of characters upon which orders depend in classification ; while in several cases of large and diversi- fied orders the characters of leading genera are also given by typical specimens. The charts will thus be found equally valuable to the beginner, the intermediate pupil, and the advanced student. A Key accompanies the charts, and they can be used with any botanical text-books, and during the season of plants they should be upon the walls of every school-room where botany is studied.

AN EXPLANATION OF THE ABBREVIATIONS USED IN THE BOTANICAL CHARTS.

Seven principal references are made with a Capital Letter, to be looked for below each Illustration ; and the subordinate parts are then noted by small letters. A reference within a O implies not magnified ; ( on the left indicates a Longitudi- nal Section, and ^ above, a Transverse.

— p petiole. -1 limb. — 1.1. ... leaflet. — s stipule.	— f. r.... -ph.... — ph. 1.. — ca . . . . — ca. s . .	floral receptacle, perianth, leaves of. calyx, sepals.
I. fl. Inflorescence (in flower). I. fr Infructescence (in fruit)	— CO — co. p. . — S	corolla, petals, stamen.
- p. peduncle. - p. p. pedicel. - b. bract. - b. g. j glume. - b. p. / pale, -g. r. general receptacle.	— s. f... — s. a. . . — s. c.. . -s. p.. -pi.... — pi. ca. — o	filament, anther, connective, pollen, pistil, carpel, ovary.
./E... ./Estivation (diagram)	-o. cl.. — o d	cell of. dissepiment.
green .... sepals, red petals.	— o. pi. . — o f	placenta, funicular cord.
yellow. . stamens, brown . . . carpels, blue ovules.	-sty... — sti . . . — oo	style, stigma, ovule
shaded. . . adhesion of whorls. 2	— oo. rh.	rhaphe.

XXVI

EXPLANATION OF ABBREVIATIONS,

Fl oo ch	chalaze	S	. Seed.
— oo f	foramen	— in. ...	integument
— n	nectary.	ts.. .	I testa.
		tg.-	/ tegmen.
		— h. ...	hile.
Fr	Fruit.	— m . . . .	micropyle.
— DC	pericarp.	— rh. . . .	rhaphe.
r en	c epicarp.	— ch....	chalaze.
me. . en	•J mesocarp*. ' endocarp	— ar . . . . — al	. arillode. albumen.
— ca	carpel.
— pe. v. . . DC cl	. . . valve, cell	E	. Embryo.
fc' U1 • ' -pe.d... — pe. p. . . — pe. f..	dissepiment. . . . placenta, funicular cord.	— ca . . . CO ... — r . . . .	. caulicle. cotyledon. . . radicle.
— pe. f . a .	. . . arillus.	-pi....	. . plumule.

CHAPTER FIRST.

THE LEAF.

EXERCISE I. The Parts of Leaves.

GATHER a variety of leaves, and begin their study by comparing them with the pictures and statements which follow.

A leaf, in its most highly-developed state, consists of three parts (Fig. i) : The flattened portion is called the

FIG. i.

FIG. 2.

lamina, or blade ; a narrower portion, connecting the blade with the plant, is termed the petiole, or leaf-stalk (Figs. 2 and 3,^) ; and a third portion, at the base of the petiole, which is either in the form of a sheath (Fig. 2, d),

BOTANY.

or consists of two little leaf-like appendages, called stip- ules, shown in Fig. 3, s s, and still smaller in Fig. i.

When the petiole is absent, the leaf is said to be sessile ; and if stip- ules are wanting, it is described as exstipulate. Fig. i represents a petio- late- stipulate leaf — that is, a fully-developed or complete leaf.

When, as in Fig. 4,

the sheath-like leaf-stem, g, ends above, at the base of the blade, /, in a little membranous appendage, lig., we call this body a ligule. It is a very common sort of stipule.

Gather leaves of all kinds, from the grass and herbs underfoot, from bushes, shrubs, and trees, and find and name the parts that compose each one of them. Say whether they are sessile or petiolate, and whether they are stipulate or exstipulate.

FIG. 3.

FIG. 4.

EXERCISE II. Venation.

The lines, fine and coarse, that are seen running through the blades of leaves, are called veins j and the various ways in which they are distributed are spoken of generally as the venation of the leaf.

When there is but one large central vein, reaching from the base to the apex of the blade, and giving off branches from its sides, it is called a midrib (Fig. i).

When there are several large veins which thus cross the blade, as seen in Figs. 5 and 6, they are called simply ribs. Branches from the rifes are known in botanical de- scription as veins, and the smallest of these lines which

THE LEAF.

FIG. 5.

FIG. 6.

branch off from the veins are known as veinlets. Point out the ribs, veins, and veinlets in all the leaves you have that exhibit them distinctly.

Now, when you hold a leaf between your eye and the light, and observe these veinlets uniting with one another in such a way as to form a kind of irregular net-work, you have in hand a reticulated or net-veined leaf (Figs, i and 6).

If, on the contrary, the leaf you are examining has veins more or less parallel to one another, or to the edge of the leaf (Figs. 7 and 8), and if they are connected by unbranched veinlets, they are termed parallel-veined leaves.

There is a further observation to be made concerning the venation of net-veined leaves. When, as in Fig. 9 or Fig. i, the midrib gives

FIG. 7.

FIG. 8-

BOTANY.

FIG. ii.

FIG. 10.

off veins right and left from its sides, it is said to be feather-veined, or pinnately veined. But when the petiole divides, at or near the base of the blade, into sever- al diverging ribs (Fig. 5), the leaf is said to be radiate, or palmate- veined. If the ribs of a net-veined leaf con- verge toward the apex, as in Fig. 7, it forms that variety of vena- tion known as ribbed.

Figs. 10 and n represent parallel-veined leaves, in which the veins take the direction seen in feather- veined and palmate -veined leaves. But in this case there is no net-work of veinlets, and so they are not net-veined. You will find many such leaves connected by unbranched veinlets. Remember that it is by the absence of this irregular network that you may know parallel-veined leaves. See Fig. 38.

Determine, in regard to all the leaves you can find, whether they are net-veined or parallel-veined ; and whether the net-veined ones are feather-veined or pal- mate-veined.

EXERCISE III. Leaf-Margins.

When the edge or margin of a leaf is smooth and even, it is said to be entire (Fig. 7). When the margin is un- even, with sharp teeth pointing toward the apex like the teeth of a saw, the leaf is said to be serrate (Fig. 12) ; if the teeth point toward the base, it is retroserrate ; if they are themselves serrate, as shown in Fig. 13, £, they are said to be biserrate. When minutely serrate, they are termed serrulate.

THE LEAF.

5

When the teeth are sharp, without pointing in any par- ticular direction, they form a dentate margin (Fig. 5) ; or,

FIG. 12.

FIG. 13.

FIG. 14.

when again similarly toothed, the margin is bidentate (Fig. i&c)- When the teeth are rounded (Fig. n), the margin is crenate j if twice rounded, as in Fig. 13, a, it is bicrenate.

FIG. 15.

FIG. 16.

FIG. 17.

Margins like the one shown in Fig. 14 are said to be crisped, or curled. When like Fig 15, they are said to be

wavy, or undulated.

6

BOTANY.

When the incisions of a leaf-margin are much deeper than these, reaching half-way to the midrib or petiole, the divisions of the blade so formed are called lobes (Figs. 1 6, 17), and the spaces between the lobes are called sinuses, or fissures.

If the blade be divided nearly to the base or midrib (Fig. 1 8), the partings are termed partitions, and the leaf v* partite; if it is divided quite to the base, or midrib, the

FIG. 20.

FIG. 18.

FIG. 19.

parts are called segments, and the leaf is said to be dissect- ed (Fig. 19). When the basal lobes, partitions, or seg- ments of a palmate leaf are themselves again divided, so that the whole resembles a bird's foot, the leaf is said to be pedatifid, pedatipartite, or pedatisected, according to the depth of the divisions. Fig. 20 represents a pedatipartite leaf.

In describing such incised leaves, they are said to be bifid, two-lobed ; trifid, three-lobed, etc. ; or bipartite, tri- partite ; bisected, trisected, etc., according to the number of lobes, partitions, or segments. Another way of describ- ing them depends upon the venation. If the leaf is feather- veined, it is said to be pinnatifid, pinnatipartite, or pin- natisected, etc. When palmate-veined leaves are deeply

THE LEAF. 7

incised, we describe them similarly as palmatifid, palma- tipartite, palmatisected.

When the terminal lobe of a leaf is large and round, with smaller lateral lobes, the leaf is lyrate (Fig. 21). When the lateral lobes have their points directed toward the base of the blade, as in Fig. 22, the leaf is said to be ruminate.

APICES. — When the apex of a leaf-blade is rounded, as in Fig. 31, it is said to be obtuse or blunt; when ob- tuse, with a broad, shallow notch in the middle, it is refuse. If this notch is sharp, as in Fig. 23, it is emar- ginate.

When a blade ends abruptly, as if it had been cut

FIG. 23.

FIG. 21.

FIG. 22.

across, it is said to be truncate ; if the truncated edge is ragged and irregular, as if it had been bitten off, the leaf is said to be prcemorse. Fig. 24 shows an acute, or sharp-pointed apex, while Fig. 27 is acuminate, or taper- pointed.

When a blade ends with a rigid point, it is cuspidate.

8

BOTANY,

If a blunt apex have a short point standing on it, it is said to be mucronate (Fig. 29).

Before going on to study the figures of leaves, it is very important that the pupil should be able to answer

FIG. 24.

FIG. 25.

FIG. 26.

FIG. 27.

FIG. 30.

FIG. 31.

FIG. 32.

FIG. 33.

accurately the questions, What parts has a leaf ? what is its venation? what its margin? and what its apex? concern- ing any and every leaf. They should be answered ex- plicitly in writing. A description of each leaf to this extent should be written and pinned upon the specimen, and the collection offered for criticism to the teacher, or, what is better, to a fellow-pupil.

NOTE.— The schedule-forms for describing leaf, stem, and inflores- cence are here omitted because they occupy too much space ; but they may be found given in full in the " First Book of Botany."

THE LEAF.

EXERCISE IV. The Figures of Leaves.

When the blades of feather-veined leaves are unequally developed on the two sides of the midrib, they are said to be oblique (Figs. 24, 25). When narrow and of nearly the same breadth at base and apex, with parallel margins, the leaf is linear (Fig. 26) ; and if ending in a sharp, rigid point, it is acerose, or needle-shaped (Fig. 28). When very narrow, and tapering from the base to a fine point, it is subulate, or awl-shaped. When broadest at the center, and three or more times as long as broad, tapering both ways, it is lanceolate (Fig. 27). When longer than broad, and slightly acute at base and apex, it is oval, or elliptical (Fig. 34). If obtuse at base and apex, as in Fig. 31, it is oblong. When a leaf is broader at the rounded base than at the apex, as in Fig. 32, it is ovate, or egg- shaped. If of the same figure, but broad- er at apex, it is obovate (Fig. 33). Fig.

FIG.

FIG. 35.

FIG. 36.

29 shows a cuneate or wedge-shaped leaf. It is broad and abrupt-pointed at apex, and tapers toward the base. Fig. 35 shows a spatulate leaf, with its broad, rounded apex, and its sudden tapering at the base,

Cordate or heart-shaped leaves (Fig. 30) have an acute apex, with their broad, round base hollowed out into two iobes. Wlien this form is reversed, as in Fig. 36, we have

IO

BOTANY.

FIG. 37.

FIG. 38.

FIG. 39.

an obcordate or inversely heart-shaped leaf. When a cor- date base is joined with a rounded apex (Fig. 37), the leaf

FIG. 40.

FIG. 42.

is reniform or kidney -shaped. Fig. 38 shows a sagittale or arrow-shaped leaf. It has an acute apex, and long, pointed basal lobes.

THE LEAF.

II

Hastate

Sagittate

Lanceolate

Subulate-- Cordate

Reniform

Ovate

FIG. 43 A.

FIG. 43 B.

Obcordate

Obovate-

Oblanceolate

Spatulate

FIG. 43 c.

The outline shown in Fig. 39 represents a hastate or halberd- shaped leaf, with its horizontally extend- ing basal lobes. In Fig. 40 these lobes are seen separated from the blade. This is an auriculate or hastate- aurided leaf. The form shown in Fig. 41 is orbicular. It is also spoken of as a peltate leaf, because the petiole is inserted on the lower face of the blade, instead of at the base. Fig. 42 represents a rounded or sub-rotund leaf. A further help in determining the figure of leaves will be found by comparing them with the outlines shown in the above diagrams, Figs. 43 A, 43 B, 43 c, 43 D.

When none of the terms given correctly describe a leaf,

Acicular

Linear

Oblong Oval

Elliptical

Rotundate -

Orbicular

FIG. 43 D.

12

BOTANY.

we can often easily and very nearly approach correctness by combining two of them, as ovate-lanceolate, linear- lance- olate, cordate-ovate, roundish-ovate, etc.

Facility and correctness of leaf - description depend upon practice. If the scholar will add the question, Fig- ure? to the other questions of Ex. Ill, and answer them all faithfully in writing, according to his best judgment, con- cerning every leaf he finds, he will soon have command of this portion of descriptive botany.

EXERCISE V. Compound Leaves.

The leaves you have been describing have only one blade, and are therefore called simple leaves ; but there are hosts of leaves, resembling Fig. 44, which, you see,

Leaflet.

Rachis. ._ ^-Petiolule.

•Petiole. •Stipules.

FIG. 45.

FIG. 44.

has several blades. A leaf with more than one blade is a compound leaf, and each of its blades is called a leaflet. Gather all the compound leaves you can find and compare them with Fig. 44. Point out and name their parts.

Some compound leaves have no rachis, but the leaflets all grow out from the top of the petiole (Fig. 45). These two kinds of compound leaves correspond to the two

THE LEAF. 13

kinds of venation of simple leaves you have been studying. Pinnately-lobed leaves pass by slight gradations first into pinnately-sected, and finally into pinnately - compound leaves. And, in the same way, palmately-compound leaves are formed. It requires a good deal of observation to de- cide correctly in all cases between deeply-divided leaves and compound leaves. If the green matter of the blade reaches around the framework as far as the midrib, and is continued along it, however slightly, the leaf is simple ; or if in palmate-veined leaves the green matter is contin- ued about the summit of the petiole, the leaf is divided and not compound. Leaflets are often jointed to the rachis or petiole. Gather all the compound leaves you can find, point out and name their parts, and say whether they are pinnate or palmate. If pinnate, say how many pairs of leaflets they have.

The leaflets of compound leaves present the same dif- ferences of margin, apex, base, incision, and outline, as the blades of simple leaves, and the same terms are used in describing them. A scientific description of a compound leaf would require that the kind of leaf should be named, and its leaflets described as if they were the blades of sim- ple leaves.

EXERCISE VI. Varieties of Compound Leaves.

Pinnately-compound leaves may have their leaflets in one, two, three, or many pairs. They may end with an odd leaflet, as in Fig. 46, when they are said to be unequally pinnate, or like Fig. 47, which is said to be abruptly or equally pinnate. If the rachis end in a tendril (Fig. 48) it is said to be a cirrous leaf. When they resemble Fig. 49, they 'are said to be interruptedly pinnate, and lyrately pin- nate when they resemble Fig. 50. When the leaflets of a pinnate leaf themselves become pinnate, as seen in Fig. 51, the leaf is said to be bipinnate. A further continuation of

BOTANY.

FIG. 47-

FIG. 46.

FIG. 49.

FIG.

FIG. 48.

FIG. si.

THE LEAF.

the process gives the appearance seen in Fig. 52, which is said to be tripinnate.

Palmately compound leaves are said to be binate, two- fingered^ or bifoliate, when two leaflets spring from a com-

FIG. 52.

FIG.

mon point (Fig. 53) ; ternate or trifoliate if they have three leaflets similarly placed (Fig. 54) ; quadrinate, four-fin-

FIG. 55.

FIG. 56.

gered, or quadrifoliate, when like Fig. 55 ; quinate, or five- fingered (Fig. 45) ; septenate, or seven-fingered (Fig. 56) ;

16 BOTANY.

and multifoliate if there are more than seven leaflets (Fig. 57). When the leaflets of a compound leaf are arranged in a pedate manner, they are described as pedate leaves. When the leaflets of palmately-compound leaves become

FIG. 57. FIG. 58.

themselves compound, the same prefixes are used as in the case of pinnately-compound leaves. Fig. 58 is a biternate leaf.

When stipules grow to the petiole, as shown in Fig. 44, they are said to be adnate ; when like Fig. 46, they are described as thorny ; when they are large and leaf-like, as seen in Fig. 48, they are said to be foliar stipules. If they grow around the stem, they are said to be sheathing; and when thin and colorless, they are described as membra- nous.

Observe, also, whether the petiole is long or short, stiff or limber, round, half-round, channeled, flattened, etc. De- scribe the color of the two surfaces of the leaves, and state also whether the surface is smooth, shiny, hairy, woolly, silky, or the like.

To describe a leaf with scientific precision requires that you should answer the following questions : Is it sim- ple or compound ? petiolate or sessile ? stipulate or ex- stipulate ? What venation, margin, and figure has it ? If compound, name the variety. Give the features of both petiole and stipules when they are present, and mention

THE LEAF.

also the color and surface aspect. Or these questions may take the form of a schedule, by placing them in a column at the left side of the paper, with space at the right for giving the answers to these questions in regard to any leaf you are describing. Thus :

SCHEDULE FIFST, FOR SIMPLE LEAVES.

Parts ?
Venation ?
Margin ?
Base?
Apex?
Lobes ?
Shape ?
Petiole ?
Color ?
Surface ?

SCHEDULE SECOND, FOR COMPOUND LEAVES.

Parts ?
No. Leaflets ?
Kind?
Variety ?

Continue to make written descriptions of all kinds of leaves, until you are so familiar with their features, and the precise words needed to describe them, that you can make an accurate, prompt, and complete oral description of any specimen that comes to hand.

CHAPTER SECOND.

ROOTS AND STEMS.

EXERCISE VII. Roots.

WHEN you are gathering plants, you will observe their roots. There are two classes of roots that are easily dis- tinguished. Try to decide, in each case, in which one of these classes the root in hand should be placed. Figs. 59 and 60 are examples of these two different classes. In Fig.

FIG. 60.

FIG. 59.

60 a mass of fibers grows downward from the base of the stem. Roots which grow in this fashion are called fibrous roots. But when you find a root which seems like a

ROOTS AND STEMS. 19

continuation of the stem, as in Fig. 59, it is a tap-root. Tap-roots are often branching, as in Fig. 59, but many

FIG. 63.

FIG. 61.

FIG. 62.

common plants have smooth tap-roots, as shown in Fig. 6 1, which is known as a conical root.

FIG. 64.

FIG. 65.

20

BOTANY.

Some of the common varieties of tap-root are easily recognized. Fusiform or spindle-shaped roots, like Fig. 62, and napiform or turnip-shaped roots, like Fig. 63, are familiar to every one.

In the case of fibrous roots, we have seen (Fig. 60) that the stem divides at once at its base into a mass of slender branches or rootlets. These fibers often become enlarged, and, when the swellings take the form seen in

FIG. 66.

FIG. 67.

Fig. 64, the root is said to be tuberculated, and each en- largement is called a tubercule. Sometimes these tuber- cules resemble the human hand (see Fig. 65), when they are said to be palmated tubercules. When a number of tubercules arise from a common point, the root is said to '^fasciculated (Fig. 66). When the fibers have numerous small swellings or nodules (Fig. 67), the root is nodulose.

ROOTS AND STEMS. 2l

EXERCISE VIII. Stems and their Parts.

Pull up any herb which has a distinct stem and com- pare the stem with the root. Herbs are plants having stems that die down to the surface of the ground every year. If the root dies as well as the stem, the plant is called an annual ; but if it lives and sends up a flowering stem the second year, and then dies, it is a biennial / while, if the root lives on from year to year and only the stem dies, the plant is perennial.

Observe the parts growing from the stem. What is at the top ? at the end of each branch ? Do you find the same structures at the tips of the roots ? Name all the differ- ences you can find between the stem and root. Com- pare an herb with Fig. 59, where the stem (/) is repre- sented as giving off leaves (ff) in a regular manner. Look at several branching stems, to find if the branches are put forth regularly. Is there any regularity in the growth of roots ? Observe, in Fig. 59, that the angle made by the leaf with the stem contains a bud, b. What do you find in this angle in living plants ? Botanists call this angle a leaf-axil, and its bud an axillary bud. Buds at the free end of stems and branches are called terminal buds.

The points on a stem at which leaves are given off are called nodes, and the spaces between the nodes are internodes.

Point out the nodes, internodes, axillary buds, and ter- minal bud of the main stem (primary stem) of as many plants as you can gather. Point out the same parts upon the secondary stems or branches.

EXERCISE IX. Buds.

The time to study winter buds is in early spring. Choose a swollen bud and observe well its outer covering.

22 BOTANY.

Is it membranous ? waxy ? gummy ? lined with down, wool, or dense hairs ? or is it varnished on the outside ? Why should these parts of winter buds be called protective cover- ings ? Are summer-formed buds naked or protected ? Can you find the young leaves within these outer bud-scales ? The way in which these tiny leaves are folded, rolled, and arranged in the bud is called vernation. To study verna- tion, look for buds that are just opening, where the young leaves still keep the shape they had when packed in the bud. If you have a magnifying-glass, you will find it use- ful now. The modes of folding and rolling are named as follows : When a leaf is folded so that the apex comes near the base, as shown in the diagram (Fig. 68), it is said to be reclinate, or inflexed ; when it is folded at the mid- rib, and the margins of the right and left half come to- gether (Fig. 69), the leaf is conduplicate ; when the leaf is plaited like a fan (Fig. 70), it \* plicate. Or a leaf may be rolled from apex to base (Fig. 71), when it is said to be circinate ; or, from one margin to the other, in a single

FIG. 68. FIG. 69. FIG. 70. FIG. 71. FIG. 72.

coil, convolute, as Fig. 72 ; or, the two margins may both be rolled inward on the upper surface of the leaf, toward the midrib, involute (Fig. 74). When they are rolled simi- larly on the under surface (Fig. 73), the form is revoluie. Leaves are always arranged in the bud either in a val- vate or imbricate manner. The best way to study their arrangement is to cut off the top of the bud with a sharp knife and look down on the cut edges, which will show, not only whether the leaves are imbricate or valvate, but other peculiarities they may exhibit.

ROOTS AND STEMS. 23

The arrangement is valvate when the edges of adjacent leaves barely touch each other (Fig. 75).

It is imbricate when the edges of the leaves overlap each other (Figs. 76, 77).

When involute leaves are applied together in a circle, without overlapping (Fig. 78), they are said to be condupli*

FIG. 73.

FIG.

FIG, 75.

FIG. 76.

FIG.

FIG. 78.

FIG. 79. FIG. 80.

FIG. 81.

cate. When conduplicate leaves overlap each other at the base (Figs. 79, 80), they are called equitant. When a con- volute leaf incloses another which is rolled up in a like manner (Fig. 81), the arrangement is supervolutc.

EXERCISE X. Stem and Leaves.

The point at which, and the mode by which, a leaf is at- tached to the stem is called its insertion. The first grown leaves (Fig. 82) are called cotyledons (c c), and the next, primordial leaves (Fig. 82, dd). Leaves are called radical when they arise at or near the surface of the ground, and cau- line when they grow from a stem with developed internodes. The small leaves upon flower-stalks are called bracts.

When a leaf is enlarged at its base and clasps the stem, it is amplexicaul, or clasping (Fig. 83). When it forms a complete sheath, as seen in Fig. 84, it is sheathing. 3

BOTANY.

FIG. 82.

FIG. 83.

FIG. 84.

FIG. 86.

FIG. 85.

FIG. 87.

FIG. 88.

FIG. 89.

ROOTS AND STEMS. 25

A decurrent leaf is formed when the blade is prolonged down the sides of the stem (Fig. 85). When the basal lobes of a leaf project beyond the stem and unite, as shown in Fig. 86, it is perfoliate. When opposite leaves unite by their bases, as in Fig. 87, they are called connate

FIG. 90. FIG. 91.

leaves. When only one leaf arises from a node, and the leaves grow alternately on different sides of the stem (Fig. 88), they are described as alternate. If there are two op- posite leaves at each node, and the successive pairs are placed at right angles to each other, they are said to de- cussate (Fig. 89). If there are three or more leaves at a node (Fig. 90), they form a whorl / and when all the leaves of a branch grow close together (Fig. 91), they are said to be tufted, or fascicled.

EXERCISE XI. Kinds of Stems.

Stems that have a firm texture can sustain themselves in -an upright position, but weak stems must either trail along the ground or attach themselves to other plants or objects for support. If they trail on the ground, they are said to be prostrate (Fig. 94). If they lift themselves by tendrils or other means, they are described as climbing (Fig. 92) ; and if they grow upward by twisting round other bodies, as shown in Fig. 93, they are said to be twining.

The stem of an herb is named a caulis ; that of a tree, a trunk ; that of grasses, a culm, and that of tree-ferns

2O

BOTANY.

and palms, a caudex. Among irregular stems the most common are runners^ like Fig. 94, which gives off from the main stem a prostrate branch, a', that sends out

FIG. 93

FIG. 94.

leaves, r, and roots, /, so producing a new plant which extends itself in like manner. There is another prostrate stem which creeps along the ground, or partly beneath it, and produces buds from its upper surface and roots from

its lower. This form of stem is k I called a rhizome (Fig. 95), where

b shows the remains of the flow- ering stem of the present year, b' terminal bud, cc scars of for- mer flowering stems, r roots.

FIG. 95.

Another form of rhizome is

ROOTS AND STEMS.

FIG. 96.

FIG. 98.

FIG. 97.

FIG. 99.

FIG. 100.

FIG. 101.

28

BOTANY.

shown (Fig. 96), which grows wholly underground, and is spoken of as a creeping root.

' Of underground stems the tuber (Fig. 97) is a familiar example. The presence of buds, or " eyes," as they are vulgarly called, proves their stem-like nature.

The bulb (Figs. 98, 99) is a kind of underground bud which gives off roots from below and a flowering stem above. In both figures you see the shortened stem a, roots b, scales <:, flowering stem d. Buds are formed in the axils of these scaly leaves. This scaly bulb has no cover- ing, and is called a naked bulb, to distinguish it from the coated or tunicated\wNQ shown in section (Fig. 100), where the scales inclose one another in a concentric manner, and have an outer membranous covering. The corm is a solid bulb, which produces one or more buds in the form of young corms (Fig. 101, a'").

In answering the questions of Schedule Third, say, as to the kind of stem, whether it is annual, biennial, or peren- nial ; whether it is erect, climbing, twining, or prostrate. If the latter, is it a runner or creeper ? or, if an under- ground stem, is it a rhizome, tuber, bulb, or corm ? Is the leaf-insertion radical or cauline ? Is the leaf-arrangement alternate, opposite, or whorled ?

By turning to the FLORA, you will see that all the

species there described are

SCHEDULE THIRD, PERTAINING TO STEMS. chiefly known from each

other by the features of leaf and stem that you have been studying ; and these differences are stated in the precise terms you have been using in schedule-work. Do not go on to study flowers till all these terms are fa- miliar.

Kind of stem ?
Leaf-insertion ?
Leaf-arrangement.
Vernation ?

CHAPTER THIRD.

THE INFLORESCENCE AND FLOWER,

EXERCISE XII. Kinds of Inflorescence.

THE way flowers are placed upon plants is called their inflorescence. When only one flower grows upon a stem, the inflorescence is solitary ; but if several flowers grow from the same stem, it is clustered. The stem of a solitary flower or of a flow- er-cluster is called a pedun- cle. The top of the pedun- cle, from which several flow- ers start together, is called the receptacle. A rounded cluster of flowers, sessile up- on the receptacle, is called a head (Fig. 102).

When, instead of a re- ceptacle, the peduncle is pro- longed, as shown in Figs. 103, 104, the portion that bears flowers is called the FIG. 102

rachis.

Fig. 103 represents a cluster of flowers that are sessile upon the rachis ; / is the peduncle ; b l>, bracts ; fl, flowers. Any cluster of flowers sessile upon a rachis is described as a spike. But if the flowers grow upon short stems

BOTANY.

FIG. 108.

FIG. IOQ.

THE INFLORESCENCE AND FLOWER.

of nearly equal length, as in Fig. 104, it is called a raceme.

The flower-stems that grow from a rachis, or from the top of a peduncle, are called pedicels.

A spadix is a spike with a thick rachis covered around by a large leaf called a spathe (Fig. 105). .

A spike with sessile bracts among its flowers is called an ament or catkin. It grows on trees and shrubs, and drops off when mature (Fig. 106).

When you find clus- ters of nearly sessile flowers in the axils of op- posite leaves, they form a glomerule.

When from the top of the peduncle there is given off a number of pedicels of nearly equal length, arranged like the ribs of an umbrella (Fig. 107), the cluster is an umbel.

When you look only

at the top of a corymb (Fig. 108) it resembles an umbel, but its pedicels are of greatly unequal length (compare Figs. 108 and 107).

A compound umbel has a small umbel, called an um- dellet, upon each pedicel (Fig. 109).

In the same way, each of the pedicels of a corymb may bear a corymb, in which case we have a compound corymb (Fig. no).

A compound raceme is formed of secondary racemes in a similar manner. When spreading, it is called a panicle.

FIG. no.

BOTANY.

Pistil.

Stamens.

EXERCISE XIII. The Parts of Flowers.

We now enter upon the study of flowers. There are a great many different kinds of flowers to be examined and compared, even in one small neighborhood. Each one of the specimens you find must be carefully observed and described. An accurate description requires that you should study each part by itself, and note down concern- ing it all the important particulars you can discover. But before you can do this you must know what parts a flower

consists of, and what par- ticulars about these parts are important.

To learn the names of these parts, then, must be your first object. Com- pare real flowers with Fig. in, which represents a flower pulled apart so that its main divisions may be fully seen. Begin with the outer leaves of a flower, and compare them with the lower circle of leaves in the diagram, and find the name of this circle. Do the same for the next circle, and so on, to the center of your specimen. Repeat this process with different flowers till you are able, at once, to point out and name the four divisions of com- mon flowers.

The outer circle of green flower-leaves is named the calyx. The inner circle of delicately colored flower-leaves is named the corolla. When both circles have the same

Receptacle.

FIG. in.

THE INFLORESCENCE AND FLOWER.

33

color, they take the name si perianth (see Fig. in). Next inside the corolla come the stamens, and within these the pistil. If there is but one circle of flower-leaves it is called

Sepal.

Sepal.

Sepal.

FIG. 112.

FIG. 113.

Sepal.

Sepal.

a calyx, whatever its color. Point out and name the differ- ent circles that compose each of the flowers you have gath- ered. But each of these flower-circles is made up of parts of the greatest importance in the study of plants, and these parts must be found and named. Each leaf of a calyx is called a sepal (Figs. 112, 113). Each leaf of a corolla is called a petal. When these circles form a perianth, its parts are called leaves.

Before finding any more parts to name, you may be- gin to note down and number the parts already found.

FIG. 114.

FIG. 115.

Prepare several flower -schedules like Schedule Fourth. The first point to be looked for and written down con- cerning a calyx or a corolla is the number of sepals OT

34

BOTANY.

of petals that compose it, as you see has been done for the flowers represented in Figs. 114, 115. When you have done this, pin the schedule to the stem of the flower it describes, so that your observations can be seen and, if need be, corrected by your teacher or a fellow-learner.

SCHEDULE FOURTH,

DESCRIBING FlG. 114.

Names of Parts.	No.
Calyx ?
Sepals.	5
Corolla ?	i
Petals.	5

SCHEDULE FIFTH,

DESCRIBING FlG. 115.

Names of Parts.	No.
Perianth ?
Leaves.	6

SCHEDULE SIXTH,

DESCRIBING FlG. 115.

Names of Parts.	No.
Perianth ?
Leaves.	6
Stamens ?	6
Filament.
Anther.
Pistil ?
Carpels.	3
Style.
Stigma.

EXERCISE XIV. Stamens and Pistil.

Prepare new flower- schedules, long enough to make room for the names of the parts of the stamens and pistil of flowers, as shown in Schedule Sixth.

Begin the study of these parts with large, well-devel-

THE INFLORESCENCE AND FLOWER. 35

oped flowers. Meadow-lilies are good examples. Sta- mens differ very much in form and proportions in different species of plants, but usually they consist of three parts, shown in Fig. 116. Find the filament and anther in your living specimens. Observe whether any of the anthers are shedding their pollen. As soon as you know just what parts of stamens are meant by these words, write them down in the third place of your sched- ule under " stamens." Count the stamens (when there are less than twelve) in each of your flowers, and write the number opposite, as you see done in the book. If a flower have more than twelve stamens, make the symbol oo, which means many.

As soon as you can point out and name the parts of stamens, begin the study of the pistil. Its parts are shown

--•Stigma.

-—Style.

Ovary.

FIG. 117.

FIG. 119. Four Carpels.

in Figs. 117, 118, 119, The ovary is at the bottom; the stigma at the top ; and the style in the middle. If you cut across the swollen ovary, you will find it full of little round bodies that will grow and become seeds. Watch the ovary as flowers fade and disappear ; look for old, faded flowers, and in them examine it. But you are not to write '" ovary " in the schedule, for the ovary is made up of parts which you are to find, if you can, and count, and put down their

36 BOTANY.

number in the schedule. These parts are called carpels (Figs. 118, 119). So, after the word "pistil" put carpels, then style, and then stigma. The carpels shown in Figs. 1 1 8, 119 are from old ripe ovaries, and may be easily counted. You can count them in Fig. 117, by the grooves down the side, showing where they have grown together. Sometimes they are not grown together at all, and so can be easily counted. If the parts of the ovary are grown smoothly together, count the styles ; and if these, too, are united, count the lobes of the stigma. Or you may cut across the ovary, as shown in Fig. 119, and count the cham- bers or cells it contains, each of which is a carpel. Count the carpels in the ovary of a lily, and compare the result with the figure giving the number of carpels in Schedule Sixth.

EXERCISE XV. Kinds of Calyx and Corolla.

Fig. 1 20 represents a calyx in which the sepals are all separate from each other, while in Fig. 121 a flower is shown in which the sepals are all grown together. You will find flowers that differ in this way, and many in which the sepals are partly joined and partly distinct.

FIG. 120.— Polysepalous Calyx. FIG. 121.— Gamosepalous Calyx.

When the sepals of a calyx are distinct from each other, so that each one can be pulled off separately, the calyx is said to be polysepalous.

A gamosepalous calyx has its sepals grown together by

THE INFLORESCENCE AND FLOWER.

37

their edges, so that, if you pull one, the whole calyx comes off.

When the petals of a corolla are distinct from each other, so that one can be pulled off without disturbing the rest, it is a polypetalous corolla, as shown in Fig. 122, where pp are the distinct petals.

When the petals of a corolla are more or less grown together, so that if

FIG. 122. — Pclypetalous Corolla.

you pull one the whole corolla comes off, it is a gamopetalous corolla (Fig.

I23)-

When the leaves of a perianth are

entirely separate from each other, it is described as poly- phyl'lous ; while, if they are grown together by their edges, however slightly, they are gamophyl' lous.

Take time carefully to compare the flower-envelopes of your specimens with these pictures and definitions. You can count the petals of gamopetalous corollas, when other ways fail, by observing their marks of union. Be cautious about calling a corolla polypetalous until you have examined several specimens of the same kind of flower. Above all things, do not guess. If you can not decide the point, consult with fellow-learners about it.

Another important feature of flowers is their regularity. A regular calyx, corolla, or perianth, has all its parts of the same size and shape (Figs. 114, 115).

38 BOTANY.

An. Irregular calyx, corolla, or perianth, has some of its parts unlike the others in size or form (Figs. 129, 131). The same terms used to describe leaves are applied to the sepals and petals of flowers. Sepals are said to be erect when turned up ; reflexed, when turned down ; con- nivent, when turned inward ; and divergent, when they spread outwafdly. Separate the regular flowers of your collection from those that are irregular. Describe the flower-leaves.

EXERCISE XVI. Kinds of Corolla.

Gather as many different kinds of flowers as you can find before you begin with this exercise, that you may have living examples of many kinds of corolla. Of course, as your observation extends, you will, all the while, be finding new forms.

A petal is made up of parts, as shown in Figs. 124, 125. The limb is the thin, broad, upper part of a petal. The claw is the part that is joined to the receptacle. Sometimes it is stem-like. Look over the flowers you have gathered, and put by themselves polypetalous ones, and in another place the gamopetalous ones. Again ex- amine the polypetalous division, and put the regular flow- ers together, leaving the irregular ones till these are looked over.

Now, there are three kinds of regular polypetalous co- rollas. The first is like Fig. 122. It has four petals grow- ing in the shape of a cross, and so is called a cruciform

— Limb.

-Claw. --• v^iaw. \i

FIG. 124.

THE INFLORESCENCE AND FLOWER.

39

FIG. 126.

FIG. 127.

corolla. When a corolla has five petals, having each a long, slender claw, as shown in Fig. 126,0, and a spreading limb (/), it is caryophylld ceous (Fig. 127).

A rosaceous corolla is shown, Fig. 128. Here there are five petals with spreading limb, but the claw is short. A liliaceous perianth has six leaves, bending away, as seen in Fig. 115.

Among irregular polypetalous corollas the most impor- tant is the papilionaceous (Fig. 129), where c is calyx ; a, wings ; car, keel. The large petal, called the banner (b), is the upper one next the stem ; the two side ones (a) are called wings, and the lower one (car) the keel, from its boat- shape. Other forms of irregular polypetalous corollas are said to be anomalous. When you have decided to which of these kinds your polypetalous corollas belong, turn to the gamopetalous specimens and separate them, the regu- lar from the irregular.

There are certain parts of a gamopetalous corolla that vary in size and form in different flowers, and that are shown in Figs. 130, 131.

The union of the petals forms the tube of a gamopeta- lous corolla. Any portion beyond this, where the petals are not united, is the limb or border. The opening into the tube is the throat.

30TANY.

, or Limb. Throat. - , ^

FIG. 131.

Fie. 134.

FIG. 132.

FIG. 135.

FIG. 136.

The kinds of regular gamopetalous corollas are tubular (Fig. 132), in which the border spreads little or none ;

THE INFLORESCENCE AND FLOWER. 41

urceolate (Fig. 133) when the tube is swollen in the mid- dle and has a narrow opening. Rotate (Fig. 134) repre- sents a rotate or wheel-shaped corolla, with short tube and flat, spreading border. Fig. 135 represents a bell- shaped, or campan'ulate corolla. Salver-form corollas (Fig. 136) have a long, narrow tube, with the border at right angles to it. A funnel-shaped corolla resembles a funnel (Fig. 123).

In the second column of the flower-schedule you have given the number of sepals, petals, stamens, and carpels of a flower, and now another wide column must be added where further observations may be written, as shown in Schedule Seventh, where the calyx and corolla are described ; but the stamens and pistil await more careful study.

SCHEDULE SEVENTH, DESCRIBING FIG. 122.

Names of Parts.	No.	Description.
Calyx ?		Polysepalous, regular.
Sepals.	4	Oval.
Corolla ?		Cruciform.
Petals.	4	Claw, long. Limb, spreading.
Stamens ?	6
Anther.
Filament.
Pollen.
Pistil ?

BOTANY.

Irregular gamopetalous corollas are labiate when the limb divides so as to resemble a pair of lips. They are of two kinds : personate, with the throat closed ; and rin-

a. Personate. b. Ringent.

FIG. 137. — Labiate Corollas.

\

FIG. 138.

FIG. 139.

FIG. 141.

gent, with the throat open (Fig. 137, a, b}. A ligulate or strap-shaped corolla is one that seems to be formed by the splitting of the tube on one side (Fig. 138).

THE INFLORESCENCE AND FLOWER.

43

Other forms of irregular gamopetalous corollas may be described as anomalous.

A strange aspect is often given to a corolla by a crown or corona, and by spurs and scales.

SCALES. — On the inner surface of the petals of many flowers, scales, and hair-like processes of various kinds, are often seen. Figs. 139, 140 are examples.

Sometimes these scales become more or less united, and form a cup-shaped part, as shown in Fig. 141. This

FIG. 142.

FIG. 143.

is called a corona, and the corolla is said to be crowned. A petal may grow outward, so as to form a bag or sac (Fig. 143) ; it is then termed saccate. Sometimes this growth is prolonged into a spur. All of the petals in Fig. 142 are seen to be spurred.

A nectary is a little gland containing sweet liquid, on the claw of a petal.

EXERCISE XVII. Symmetry of Flowers.

Look carefully at the pictures and explanations of this exercise. Count the sepals in Fig. 144. Count the petals and stamens. Observe the two-lobed stigma of the pistil, which shows the number of carpels. Has each of the

44

BOTANY.

floral circles the same number of parts ? Then it is a sym- metrical flower. Any flower that has the same number of parts in each of its circles is symmetrical ; and even if some of the circles have just twice, or three or four times, as many as others, it is still symmetrical. Count the parts

FIG. 144. — Binary Symmetry.

FIG. 145. — Ternary Symmetry.

FIG. 146. — Quaternary Symmetry.

FIG. 147. — Quinary Symmetry.

in the floral circles of Fig. 145. Is this flower symmetri- cal ? Does Fig. 146 represent a symmetrical flower? 147? These kinds of symmetry are described as binary, tern- ary, qtiaternary, and quinary. Examine the flowers you have collected and discover, if you can, the symmetrical ones, naming the symmetry they show.

EXERCISE XVIII. Complete and Incomplete Flowers.

A complete flower consists of calyx, corolla, stamens, and pistil. If any one or more of these flower-circles is absent, the flower is incomplete.

THE INFLORESCENCE AND FLOWER. 45

If you have the botanical charts, look at the magnified flowers represented on them, and point out the symmetri- cal ones. Find also examples of complete and incomplete flowers.

The stamens and pistil of flowers have been called essential organs, because seeds can not be formed without their presence. As the calyx and corolla cover and nour- ish these, they have taken the name of protecting organs.

When the protecting organs are both present in a flower, it is said to be dichlamyd' eous.

When there is only a calyx, it is monochlamyd' eous.

If both calyx and corolla are absent, it is achlamyd' eous, or naked. A perfect flower (Fig. 148) has both the essen- tial organs ; while, if one of these be absent, it is imperfect (Figs. 149, 150) ; and, if both are wanting, it is said to be

FIG. 148. FIG. 149. FIG. 150.

A Perfect Flower. Imperfect Flowers.

neutral. A staminate flower has no pistil. A pistillate flower has no stamens. Staminate flowers (Fig. 149) are said to be sterile, because they do not produce seed. They are also spoken of as male flowers. Pistillate flowers are said to be fertile, because they may bear seed. They are also called female flowers (Fig. 150).

A perfect flower is indicated thus, £ .

A staminate, sterile, or male flower, thus, $ .

A pistillate, fertile, or female flower, thus, $ .

BOTANY.

When both staminate and pistillate flowers grow upon the same plant (Fig. 151), it is said to be monoecious.

When staminate and pistillate flowers grow upon sep- arate plants (Figs. 153 and 154), such plants are said to be

FIG. 3152. — Pistillate Flower, from Catkin (Fig. 153).

FIG. 151. — A Monoecious Planf.

FIG. 153.— Female Catkin of a Dioecious Plant.

di&cious. Fig. 152 represents a pistillate flower from the female catkin (Fig. 153). Fig. 155 represents a staminate flower from the male catkin (Fig. 154). These catkins grow upon different trees ; so the willow from which they were taken is dioecious.

THE INFLORESCENCE AND FLOWER.

47

When staminate, pistillate, and perfect flowers are all found upon the same plant, it is polygamous.

When you have filled out a schedule with the descrip- tion of a flower, ask yourself the following questions about it, and answer them, if you can, in writing, at the back of the schedule :

Is this flower symmetrical or unsymmetrical ? Is it complete or incomplete ? Is it dichlamydeous, monochla-

FIG. 155.

Staminate Flower, from Catkin (Fig. 154).

FIG. 154, Male Catkin of a Dioecious Plant.

FIG. 156.

mydeous, or achlamydeous ? Is it perfect or imperfect ? Did it grow upon a monoecious, dioecious, or polygamous plant ?

EXERCISE XIX. Form of the Receptacle and Insertion of Floral Organs.

INSERTION. — In botanical language, organs are said to be inserted at the place from which they seem to grow. For instance, in Fig. 156 it will be seen that the pistil is inserted upon, or seems to grow from, the receptacle ; the stamens are inserted upon the corolla ; the corolla is in- 4

48

BOTANY.

serted upon the receptacle, and the calyx also is inserted upon the receptacle.

Look at the magnified flowers shown in section on Chart i, and point out the receptacle in each case. Are all these receptacles alike in form ? State, in regard to each flower, where the pistil is inserted ; where the sta- mens ; where the corolla ; and where the calyx. Which floral whorl in each flower occupies most space upon the receptacle ? Are these flowers perfect ? Are they com- plete ? Are they symmetrical ?

Repeat these observations upon the magnified flowers shown in section in Chart 2 ; in Charts 3, 4, 5, 6.

Make a longitudinal section of each of your living flowers, and look for the insertion of the floral organs. If you sometimes fail to discover it, do not be discouraged. It will not, of course, be as clearly visible as it is shown to be on the chart. Try again. Make frequent attempts, as failure is often due to lack of experience.

EXERCISE XX. Polyandrous Stamens.

We now return to the study of the flower at the point where it was left in Schedule Seventh.

The third column of this schedule, you remember, is the place where you wrote whether the parts of floral whorls are grown together or not. You have studied the calyx and corolla to learn whether their parts are grown together. If the sepals are not grown together, you say the calyx is polysepalous ; and, if they are grown together, you say it is gamosepalous. So, also, when the petals of the corolla are distinct, you say the corolla is polypetalous ; and, when grown together, gamopetalous.

Gather all the flowers you can find, and observe the stamens to see if they are grown together. Put aside all that are in the least grown together.

THE INFLORESCENCE AND FLOWER.

49

Now look at the flowers with distinct stamens, and put by themselves all that have more than twelve.

A flower with more than twelve distinct stamens is said to have its stamens indefinite.

They are definite when there is a fixed number not above twelve.

Separate those with indefinite stamens, and label them polyandrous (from poly, many, and andria, stamens), which means many distinct stamens.

Now examine the flowers with definite stamens, and label each one with the name that, in the following table,

FIG. 157. Didynamous Stamens.

FIG. 158. Tetradynamous Stamens.

is placed opposite its number of stamens. The Greek numeral prefix denotes the number of distinct stamens :

Mon-androus — one stamen. Di-androus — two stamens. Tri-androus— three stamens. Tetr-androus — four stamens. Pent-androus — five stamens. Hex-androus — six stamens.

Hept-androus — seven stamens. Oct-androus — eight stamens. Enne-androus — nine stamens. Dec-androus — ten stamens. Dodec-androus — twelve sta- mens.

Poly-androus — more than twelve.

BOTANY.

Like the word polyandrous, these terms apply only to distinct stamens ; at the same time they have the impor- tant advantage of giving the precise number.

But, if a tetrandrous flower has two stamens long and two short (Fig. 157), it is said to be didynamous j and, if an hexandrous flower has four stamens long, and two short (Fig. 158), it is said to be tetradynamous.

These words, applied to the stamens of a flower, give at the same time their number, the fact that they are dis- tinct, and the proportion of long to short ones.

Can you find upon the charts any flowers with tetra- dynamous stamens ? Have any of them didynamous sta- mens?

EXERCISE XXL The Growing together of Stamens.

Having disposed of all your flowers with distinct sta- mens, next examine those with united stamens.

First observe whether they have grown together by their filaments, or by their anthers. All those having their anthers united, wheth- er into a tube, around the pistil, or in any other way, may be put together and la- beled syngenesious (Figs. 160 and 161).

FIG. 159. Syngenesious Stamens.

FIG. 160. FIG. 161.

Synganesious Stamens. Syngenesious Stamens.

THE INFLORESCENCE AND FLOWER. 51

Fig. 159 shows this tube laid open. Those that have grown together by their filaments have to be further studied. Are all the filaments grown together in one bundle ? If so, the stamens are monadelphous (Fig. 162).

FIG. 162. Monadelphous Stamens.

FIG. 163. Diadelphous Stamens.

FIG. 164. Tri- or Polyadelphous Stamens.

FIG. 165. — Polyadelphous

Are they grown together in two bundles ? Then they are diadelphous (Fig. 163).

Are they in three or more bundles ? Then we say they are polyadelphous (Figs. 164 and 165). Fig. 164 has one bundle cut away.

The number and length of the hard words in this exer- cise may discourage pupils, but by use they will become familiar, and they will then greatly help the process of description.

52 BOTANY.

Collect all the plants in the neighborhood, from garden, road-side, fields, and woods, and, in describing their sta- mens, you will become well acquainted with all the neces- sary terms.

EXERCISE XXII. The Growing together of Carpels.

You have been accustomed to counting the carpels of flowers, and you are now to find whether or not they are grown together.

All such as are not grown to- gether at all you may label apocar- pous (Fig. 1 66).

Those that are grown together, whether slightly at the base of the ovary or through the whole length FlG l66> of the pistil, you label syncarpous

Apocarpous Pistil. (FigS. 167, l68).

Find all the apocarpous ovaries pictured upon the charts. All the syncarpous ones.

Find also the apocarpous ovaries in your collection of flowers. The syncarpous ones.

For this exercise, faded flowers, and even those that have lost their floral leaves, will serve better than such as are fresh.

COHESION. — In botany this word is used for the grow- ing together of parts with their fellows, as of petals with petals, carpels with carpels. Figs. 173 and 177 illustrate this.

Professor Henslow, the author of the flower-schedule we are using, places the word cohesion above the third column, and devotes it to observations upon the cohesion of parts in flowers.

Fig. 169 represents half a buttercup. It has been sliced down through the middle, making what is called a vertical section of the flower, that you may see the struct-

THE INFLORESCENCE AND FLOWER.

53

lire of the stamens and pistil. This flower is used here because of its simplicity, its parts being all quite distinct from each other. It is without cohesion, and, in describ-

FIG. 167. Syncarpous Pistil.

FIG. 168. Syncarpous Pistil.

ing it, you have to use terms which apply to distinct stamens and carpels.

The learner will, of course, provide himself with a real flower, and fill out a schedule from his own examination of it. The buttercup is easily found, for it grows almost everywhere, and blossoms throughout the summer. I must

FIG. 169.

insist that the pupil be not content with simply looking over the description in the book. The example is given, not as a substitute for the pupil's own effort, but as a

54

BOTANY.

means of testing his observations ; of letting him know whether his own way of carrying out the schedule descrip- tion is the correct one. Any lack of confidence he may feel in beginning a new process will disappear when he sees that his observations and statements agree with the printed ones. A schedule or two thus employed, when he is beginning to use new terms, will assist him in gaining self-reliance.

Schedule Eighth, describing Fig. 169, gives this ar- rangement :

SCHEDULE EIGHTH.

Organs.	No.	Cohesion.
Calyx ? Sepals.	5	Polysepalous.
Corolla ? Petals.	5	Polypetalous.
Stamens ?	00	Polyandrous.
Pistil ? Carpels.	00	Apocarpous.

Questions upon the Buttercup {Fig. 169) and Schedule.

Is there cohesion in the calyx ?

What word in the schedule expresses this ?

Is there cohesion in the corolla ?

How is this stated in the schedule ?

Are the stamens definite or indefinite ?

Are they grown to each other ?

What word in the schedule answers this question ?

Dp the carpels cohere ?

How is this expressed ?

THE INFLORESCENCE AND FLOWER.

55

Questions reviewing the subject of Cohesion in the Parts of a Flower.

What is meant by cohesion in botany ?

How do you describe a calyx with no cohesion (Fig.

FIG. 170. Polysepalous, no cohesion.

FIG. 171. Gamosepalous, coherent.

170)? A corolla (Fig. 172)? Stamens (Exercise XX)? Pistil (Fig. 176)?

When the sepals are coherent, how do you describe the calyx (Fig. 171) ? The corolla (Fig. 173) ?

FIG. 172. Polypetalous, no cohesion.

FIG. 173. — Gamopetalous, coherent.

When stamens cohere by their anthers, what word do you use in describing them (Figs. 159, 160, 161) ?

When, by their filaments in one bundle, what word is used (Fig. 162) ?

BOTANY.

In two bundles (Fig. 163) ?

In three or more bundles (Figs. 164 and 165) ?

How do you describe a coherent pistil (Fig. 177) ?

FIG. 175. Triadelphous, Stamens coherent.

FIG. 174. — Polyandrous, Stamens not coherent.

FIG. 176. Apocarpous, no cohesion.

FlG. 177. — Syncarpous, coherent.

There are a few common flowers found everywhere in the country, in which there is no cohesion ; but, in most

flowers, the parts of some of the floral circles will be found more or less united. Figs. 178, 179, and 180 represent the flower of the Saint - John's - wort. Fig. 179 is a vertical section of the flower, and Fig. 180 one Fic.~i78. of the bundles of stamens.

THE INFLORESCENCE AND FLOWER. 57

FIG. 179.

Schedule Ninth, describing Fig. 178, is an example where cohesion of stamens and pistil is described.

SCHEDULE NINTH.

Organs.	No.	Cohesion.
Calyx ? Sepals.	5	Polysepalous.
Corolla ? Petals.	5	Polypetalous.
Stamens ?	CO	Tri- or Polyadelphous.
Pistil ? Carpels.	3	Syncarpous.

By turning to page 63 you will see that another column is there added to the schedule. After three more exer- cises, which introduce new observa- tions and new terms, this addition be- comes necessary. Your attention is called to it now, to give urgency to the advice that you make diligent use

FIG. 180.

5g BOTANY.

of the present schedule in describing all kinds and degrees of cohesion in all sorts of flowers. If you do this, when the time comes to add this fourth column, your mind will be free to attend to the new features that belong to it. The terms expressing cohesion being familiar, there will be no confusion of thought, and you will enter upon the new observations with ease and pleasure.

EXERCISE XXIII. Union of Floral Whorls with each other— Calyx and Pistil.

In your study of pistils, did you always find the calyx at the base of the ovary ?

Have you ever seen upon the apex of ripened fruit the withered calyx, or the scar left by its fall ?

Point out upon the charts all the cases where the calyx is below the ovary.

FIG. 181.

Inferior Calyx. Superior Ovary.

FIG. 182. FIG. 183.

Superior Calyx.— Inferior Ovary.

THE INFLORESCENCE AND FLOWER. 59

Point to those where the calyx is above it.

Is the calyx in all the pictures upon the chart either at the base or at the apex of the ovary ?

For this exercise select flowers that have their parts so well developed that you can see distinctly where each organ is inserted. Take, for example, the morning-glory, and observe whether the calyx arises below the ovary or not. If you find it is inserted below the ovary, label it calyx below, or inferior (Fig. 181), and lay it aside. If the calyx is inserted above the ovary, label it calyx above, or superior (Fig. 182). Of course, if the calyx is below the ovary, or inferior, the ovary will be above the calyx, or superior ; and, when the calyx is superior, the ovary will be inferior.

Examine all your flowers in the same way, giving each its proper label. If some specimens have the calyx in- serted neither at the bottom nor at the top of the ovary, but somewhere along its side (Fig. 184), you describe these as having the calyx half inferior, and the ovary half superior. These words, in- ferior and superior, came into use before the facts about this matter were under- stood. We now know that when the calyx seems to be inserted at the top of , CalyXi haif inferior, the ovary, it is really inserted on the re- Ovary, half superior. ceptacle, and has its tube grown to the ovary. The true expression is "calyx adherent to ovary," in place of calyx superior ; and " calyx free from ovary," in place of calyx inferior. But the words superior and inferior are in general use, and so are retained in schedule description.

6o

BOTANY.

EXERCISE XXIV.

The Union of Floral Whorls with each other. There is, perhaps, no part of the study of plant-forms that will tax your patience as much as the subject of this exercise.

Try first to determine the insertion of the corolla. Compare the arrangement of parts in each of your

flowers with that shown in Fig. 185, and, when you find the corolla insert- ed below the ova- ry, and free from the calyx, label the specimen corolla, hypogynous.

Examine the remainder of your flowers, and, when you find one with the corolla insert- ed, as shown in Fig. 186, say corolla upon the calyx, or perigynous.

How is the corolla inserted in Fig. 187? Point out upon the charts instances where the corolla has a similar insertion.

Look at the flowers not yet described, and, if you find cases where the corolla is inserted upon the ovary, describe them as epigynous, from <?//', upon, and gynia, pistil (Fig. 1-87). If not quite certain about these characters in your specimens, write your label with a mark of interrogation, to show doubt. Do not be discouraged if these points of structure remain for some time troublesome ones to dis- cover. Try to find them out, and, if you succeed, it is well ; but if you fail, your labor will not be lost.

FIG. 185.— Corolla, hypogynous.

THE INFLORESCENCE AND FLOWER. 6 1

As some flowers upon the same plant are more per- fectly developed than others, you should gather several of each kind, and examine them all, to find the best exam- ples of the structure you are studying.

FIG. 186. — Corolla, perigynous.

FIG. 187. — Corolla, epigynous.

Look at the flowers in Chart i, and observe in each case whether the corolla arises from the receptacle, and whether the calyx is free from the corolla.

Find upon the other charts all the cases where the corol- la is inserted under the ovary, and is free from the calyx.

Observe the flowers on Chart 2. Where is the corolla inserted in these figures ? Can you find upon the other charts any pictures of flowers where the corolla has a simi- lar insertion ?

EXERCISE XXV. Union of Floral Whorls with each other — Stamens.

If the stamens have the same insertion as the corolla, use the same words to describe them. For instance, in Fig. 1 88 the stamens are hypogynous ; in Fig. 189, perigy- nous; in Fig. 190, epigynous.

When you find them arising from the corolla, as seen in Fig. 191, they are said to be epipetalous.

Sometimes they are consolidated witji the pistil, as shown in Fig. 192 ; then they are gynandrous, or upon the pistil.

62

BOTANY.

Observe the flowers upon the chart in this respect.

Examine all the flowers you can find, and label them by the insertion of the stamens ; as, stamens under the ovary, or hypogynous ; stamens upon the calyx, or perigy- nous ; stamens upon the ovary, or epigynous ; stamens upon the corolla, or epipetalous ; stamens consolidated with the pistil, or gynandrous.

Adhesion in botany means the growing together of dif- ferent floral whorls, while cohesion, as you have seen, means the growing together of the parts of the same whorl.

The word free is used to express absence of adhesion, and the word distinct, absence of cohesion.

FIG. 188.— Stamens, hypogynous. FIG. 189.— Stamens, perigynous

FIG. IQI. FIG. 192.

Epipetalous Stamens. Gynandrous Pistil.

FIG. 190.— Stamens, epignyous.

THE INFLORESCENCE AND FLOWER.

In Fig. 193 there is neither cohesion nor adhesion. Not only are the sepals and petals distinct from each other, not only is each stamen and each carpel distinct, but the whorl of sepals is inserted upon the receptacle, and is free

FIG. 193. Parts, distinct. Organs, free.

FIG. 194.

from the whorls within it. The corolla is inserted upon the receptacle, and is also free. The stamens and pistil are also inserted upon the receptacle, and are likewise free.

The last column of Schedule Tenth, describing Fig. 194, is for the record of observations on adhesion.

SCHEDULE TENTH.

Organs.	No.	Cohesion.	Adhesion.
Calyx ? Sepals.	5	Polysepalous.	Inferior.
Corolla? Petals.	5	Polypetalous.	Hypogynous.
Stamens ?	00	Polyadelphous.	Hypogynous.
Pistil ? Carpels.	oo	Apocarpous.	Superior.

64

BOTANY.

Questions upon the Buttercup (fig- 1 94) and its Schedule. Is the calyx free or adherent ? How is this expressed in the schedule ? Where is the corolla inserted ? How is this stated in the schedule ? Are the stamens free or adherent ? Where are they inserted ? How is this expressed in the schedule ? Is the pistil free or adherent ? How is this written in the schedule ? This is the complete flower -schedule of Professor Henslow, which was used by his classes both at Cam- bridge University and at his parish school at Hitcham. Complaints have been made that it is difficult. Pupils who commence its use before they fully understand the features of plants to which it calls attention will, no doubt, get confused when they attempt to fill up the blanks one after another, but those who have examined a variety of flowers, in connection with the foregoing pages, will have no such trouble.

The presence or absence of cohesion and adhesion in flowers is of great importance in deter- mining the relationships of plants, and scholars can not do better than continue the use of this schedule throughout the sum- mer season, along with the mak- ing of an herbarium. Always write from your own observation. Never give a word of description unless it be of something your own eyes have seen, and that you could point out to any one who might contradict you. We give some further examples of the use of the schedule in flowers of very un- like structure.

FIG. 195.

THE INFLORESCENCE AND FLOWER. 65

Find living flowers like those here described, and fill out schedules of them yourself. Be careful not to copy statements from the book. Depend upon your own judg- ment.

Fig. 195 represents a flower of cow-parsnip. That of the carrot, or any umbelliferous plant, will do as well.

SCHEDULE ELEVENTH, DESCRIBING FIG. 195.

Organs.	No.	Cohesion.	Adhesion.
Calyx ? Sepals.	5	Gamosepalous.	Superior.
Corolla ? Petals.	5	Polypetalous.	Epigynous.
Stamens ?	5	Pentandrous.	Epigynous.
Pistil ? Carpels.	2	Syncarpous.	Inferior.

FIG. 196.

66

BOTANY.

Fig. 196 shows a vertical section of the flower of daffo- dil. It is common enough in gardens ; but, if there are pupils who can get neither this flower, nor the jonquil, nor the snow-drop, they can certainly find a lily of some kind, wild or cultivated, and observe the features in which it is unlike this picture.

SCHEDULE TWELFTH, FOR FIG 196.

Organs.	No.	Cohesion.	Adhesion.
Perianth ? Leaves.	6	Gamophyllous. Crowned.	Superior.
Stamens ?	6	Hexandrous.	Perigynous.
Pistil ? Carpels.	3	Syncarpous.	Inferior.

Fig. 197 is a blossom of wild geranium. Fig. 198 shows its stamens and pistil. The flower of the garden geranium will serve in its place, if it can be more easily obtained.

SCHEDULE THIRTEENTH, FOR FIG. 197.

Organs.	No.	Cohesion.	Adhesion.
Calyx ? Sepals.	5	Polysepalous.	Inferior.
Corolla ? Petals.	5	Polypetalous.	Hypogynous.
Stamens ?	10	Decandrous.	Hypogynous.
Pistil ? Carpels.	5	Syncarpous.	Superior.

THE INFLORESCENCE AND FLOWER.

67

FIG

FIG. 198.

EXERCISE XXVI. The Receptacle.

The peculiarities of plants pointed out in this exercise are not very common. But pupils who are using the flower-schedule, and collecting all the plants they can find, will be sure to meet with examples of them sooner or later. This exercise should, therefore, be carefully

FIG. 199. — Convex Receptacle.

FIG. 200. — Receptacle, greatly enlarged.

read and borne in mind, so that when the things it de- scribes are met with they will be recognized.

You have seen the receptacle forming a swelling like that of Fig. 199, and gradually expanding into a structure like Fig. 200. Sometimes the receptacle is prolonged be*

68

BOTANY.

tween the carpels, and coheres with their styles, which separate from it at maturity, as seen in Figs. 201 and 202.

FIG. 201.

FlG. 202.

FIG. 203.— Cup- shaped Receptacle.

It sometimes appears as a cup-shaped depression (Fig. 203), in which the pistil is almost concealed, and again as shown in Fig. 204.

FIG. 204.— Elevated Fleshy Receptacle.

FIG. 205. — a. Anthophore.

When the receptacle becomes elongated, so that one circle of floral organs is separated from another by a stalk- like internode ; the circle thus raised is said to be stipitale,

THE INFLORESCENCE AND FLOWER. 69

and the stalk supporting it is called a stipe. In Figs. 205 and 206 the stamens, pistil, and corolla are stipitate, and the stalk which bears them is the stipe.

When the stipe supports corolla, stamens, and pistil, it is called an anthophore (Fig. 205). When it supports only stamens and pistil, it is known as \kzgonophore (Fig. 206, a).

FIG. 206. — a. Gonophore.

EXERCISE XXVII. Appendages of the Receptacle.

Examine the receptacle in the magnified flowers upon Charts i, 2, 3, and 4.

Carefully observe the space between the calyx and ovary in the following figures. You see a sort of fleshy

FIG. 207.

Hypogynous

Disk.

FIG. 208.

Hypogynous

Disk.

FIG. 209. — Hypogynous Disk.

rim around the pistil, which is called a disk. It takes on very different shapes in different plants. In Figs. 207 and 208 it is merelv a raised cushion ; in Fig. 209 it is seen

BOTANY.

partly inclosing the ovary. In Figs. 210 and 211 the disk is seen surrounding the ovary; while in Figs. 212

FIG. 210.— Perigynous Disk.

FIG. 212. FIG. 213.

Epigynous Disk. Epigynous Disk.

FIG. 211. — Perigynous Disk.

FIG. 214.

FIG. 218.

FIG. 216.

FIG. 217.

THE INFLORESCENCE AND FLOWER. j\

and 213 it is shown above the ovary, and at the base of the style.

The little glands upon the receptacle are known as nectaries. They contain sweet fluids, and are found among the stamens (Figs. 214, 215) or at the base of the pistil, forming a part of the disk (Figs. 216, 217, 218).

Turn to pages 186 to 191, and observe that the orders of flowering plants are divided into the following groups, according to the characters of cohesion and adhesion they exhibit :

1. Inferior Polypetalous Exogens.*

2. Discifloral Polypetalous Exogens.

3. Superior Polypetalous Exogens.

4. Superior Monopetalous Exogens.

5. Inferior Monopetalous Exogens with Regular Flowers.

6. Inferior Monopetalous Exogens with Irregular Flowers.

7. Apetalous Exogens with Perfect Flowers.

8. Apetalous Exogens with Imperfect Flowers.

9. Superior Endogens. f

10. Inferior Endogens.

11. Gymnosperms.J

* Outside-growers. Stems that grow by an annual addition of a ring of wood outside the previous wood, and hence they are called Exogens (from two Greek words signifying outside growers}. All the trees and large shrubs of temperate and cold climates are exogenous in their growth. Multitudes of herbaceous plants are also classed as exo- gens. They may be known by their venation. All plants with net- veined leaves are exogens. The seeds of exogenous plants contain a two-leaved embryo (see Ex. X), and are hence called dicotyledonous plants.

f Inside-growers. Stems that grow by the addition of new wood directed toward their interior. All plants with parallel-veined leaves are endogens. Their seeds also contain a one-leaved embryo, whence the name monocotyledonous plants.

\ See page 161. 5

CHAPTER FOURTH.

COMPARING AND CLASSIFYING PLANTS.

EXERCISE XXVIII. Plant Characters and Affinities.

You are now to take a step forward in the study oi plants. Having acquired considerable knowledge of their parts by direct observation, you will begin to compare them— to note the resemblances and differences of whole plants, and, by these resemblances, to arrange or group them in a systematic way. This is classification

COMPARING AND CLASSIFYING PLANTS.

73

You have been classifying the parts of plants ever since you commenced observing them. For instance, those with parallel-veined leaves have been classed by themselves, and those with flowers in umbels have been classed to- gether, and kept distinct from such as blossom in heads and panicles ; but your groupings have thus far been made upon single features of plants. Now, however, you know their parts so well that you can begin to compare whole plants with each other.

If, for example, you have put into one group all square- stemmed plants, simply because they have square stems, it is time to consider whether these plants are alike in other respects. " Oh, yes," some of you will say ; " they have opposite leaves." Well, look at their inflorescence ; do they all agree in that ? Is it always axillary ? Are the flowers similar in all the square-stemmed plants you know? When you have answered these questions, you will under- stand what I mean by studying plants as wholes.

Provide yourself with the following plants : The but- tercup (which is found almost everywhere), the wild col- umbine, and the poppy. If the columbine is not to be found, get monk's-hood, or larkspur, or anemone, and pro- ceed with them in the way pointed out for the columbine. If the poppy can not be found, you might substitute blood- root or celandine. Having got the plants, proceed accord- ing to the plan laid down, and do not accept the statements or conclusions of the book, unless, on comparing them with your own plants, you see that they are true.

There are two botanical expressions of which, at the outset, you should learn the meaning. One of these is the characters of plants, and the other the affinities of plants. And, first, what is meant by plant-characters ?

If you will describe a buttercup, I think we can easily find just what is meant.

You say, " CALYX, sepals, 5, polysepalous, inferior ; COROLLA, petals, 5, polypetalous, hypogynous ; STAMENS,

74 BOTANY.

many, hypogynous ; PISTIL, carpels, many, apocarpous, superior. It has simple, exstipulate, alternate divided leaves ; petiole spreading at base ; stem, erect ; flowers, in a loose cluster ; juice, watery, acrid."

Now, this is a description of a particular buttercup, and yet it applies to all buttercups. Are all buttercups, therefore, exactly alike ? By no means. They differ in size, shape, thriftiness, number of blossoms, etc. ; but, in our botanical description, we do not record these indi- vidual peculiarities.

Well, the points of form and structure in which all buttercups agree — that is, their permanent features — are called by botanists the characters of the buttercup. All such unchanging features of plants are plant-characters. A plant is an assemblage of characters, and the description of a plant is but a list of its characters.

Now, it is by comparing groups of characters that we reach the idea of affinities. If, as we have seen, each plant bears a fixed group of characters, the resemblance of one plant to another is only the resemblance of one group of characters to another. Let us make such a comparison between the buttercup and the columbine.

Do not rely upon the descriptions in the book, but make similar tables yourself.

BUTTERCUP. — Flower. Calyx. — Sepals, 5, polysepalous, inferior.

Corolla. — Petals, 5, polypeta- lous, hypogynous, obcordate, yellow.

Stamens. — oo, hypogynous.

Pistil. — Carpels, oo, apocar- pous, superior.

CCLUMBINE. —Flower.

Calyx. — Sepals, 5, polysepalous, inferior, colored like the pet- als.

Corolla.— Petals, 5, polypeta- lous, hypogynous, spurred, red.

Stamens. — oo, hypogynous.

Pistil. — Carpels, 5, apocarpous, superior.

Comparing the above lists, you see agreements and differences. The calyx and corolla of one plant agree

COMPARING AND CLASSIFYING PLANTS. 75

with those of the other in number of parts and in the position of parts. They differ only in color and outline. The stamens of one are like those of the other in being numerous and hypogynous. The pistils agree in structure, but differ in the number of carpels. If you compare the leaves, stems, inflorescence, etc., you also get a list of their resemblances and differences. This is comparing plants by the groups of characters they present.

These resemblances of character among plants are called their affinities.

The degree of affinity between plants depends upon two circumstances : First, upon the kind of characters in which they agree ; and, second, upon the number of char- acters in which they agree.

The characters of plants differ in importance. Color, size, and odor, being usually more variable than position and number, they are said to be less important than these. The characters of the leaf, for the same reason, are not usually as important as those of the flower. In the be- ginning of study, you may assume that those plants have the strongest affinities that resemble each other most in the characters recorded in the cohesion and adhesion col- umns of the schedule.

To make this plainer, compare the poppy and buttercup, as, before, you compared the columbine and buttercup.

BUTTERCUP.

Calyx. — Sepals, 5, polysepalous, inferior.

Corolla. — Petals, 5, polypeta- lous, hypogynous.

Stamens. — Polyandrous, hypo- gynous.

Pistil. — Carpels, many, apo- carpous, superior.

Leaves. — Net-veined, divided.

Juice. — Watery.

POPPY.

Calyx.— Sepals, 2, polysepalous, inferior.

Corolla. — Petals, 4, polypeta- lous, hypogynous.

Stamens. — Polyandrous, hypo- gynous.

Pistil. — Carpels, many, syn- carpous, superior.

Leaves. — Net-veined, divided.

Juice. — Milky.

76 BOTANY.

To find which has the strongest affinity for the butter- cup, the columbine or the poppy, all that is necessary, at present, is, to ascertain which of them is nearest like the buttercup in respect to cohesion and adhesion of the parts of the flower. ,

On examination, you see that the columbine, like the buttercup, is perfectly destitute of cohesion, while in the poppy you have a coherent, or syncarpous, pistil. This settles the question. The affinity of the columbine for the buttercup is greater than the affinity of the poppy for the buttercup.

If you compare their leaves, you will find those of the poppy more like buttercup-leaves than are those of the columbine, but differences in leaf-structure do not usu- ally signify as much in classification as differences in the pistil.

Compare, in the same way, the hollyhock and the Saint-John's-wort with mallows, and decide which has the strongest affinity for the mallows.

Compare the flower of the locust and of the geranium with that of the pea or bean.

I mention these plants, not because they are useful above all others for your purpose, but to start you in the work. It really matters little what plants you take, if you only carefully compare the group of characters of each one with that of the others, and endeavor to discover the affinities they present.

EXERCISE XXIX. How to begin Classification.

If you have made the comparisons pointed out in Ex. XXVIII, you are prepared for an explanation of the plan by which you are to begin to classify plants. As we made use of the buttercup and columbine to learn the meaning of affinity in botany, a little further statement about them

COMPARING AND CLASSIFYING PLANTS. 77

will, perhaps, be helpful before we pass to the regular work of the exercise.

The buttercup thrives best in low, damp places. It is like frogs in this respect ; and, because of this, it is named after them. Its botanical name is Ranunculus, from Rana, a frog. The Ranunculus has certain characters with which you are familiar. Now, when you find other plants which are very much like it, that is, which present nearly the same group of characters, particularly those of cohesion and adhesion, you class them with it, you say they belong with the buttercup ; or, in more botanical language, they belong to the Ranunculaceae. In some regions this plant, from the form of its leaf, is called the Crowfoot, and plants closely resembling it are said, therefore, to belong to the Crowfoot family. Now, the resemblance of the columbine to the buttercup entitles it to belong to the Ranunculaceae. The monk's-hood and larkspur also be- long to the same family, and this will give you some idea of the degree of similarity that should exist between mem- bers of one family.

Our object in the present exercise is, to fix upon a method by which to begin the work of classifying plants, by comparing the groups of characters they present, and putting together those that are most alike.

Get a pocket note-book. Write in it, boldly and plain- ly, the flower-schedules of the following plants : Butter- cup, shepherd's -purse, mustard or radish, catchfly, mal- lows, Saint-John's-wort, clover, pea or bean, wild rose, strawberry, geranium, violet, morning-glory.

Now, why have we put these particular schedules into the note-book ? Compare them with each other. Do you not see that the statements in the cohesion and adhesion columns are widely unlike ? This is why we have chosen them. They are so many different examples of the make- up of flowers, and you have simply to compare each flower you describe with one and another of these examples, to

78 BOTANY.

see which it most resembles. If unlike them all, then set up your new acquaintance as another example, and see if you can find any similar plants in the course of the summer. So, do not confine yourself to comparisons be- tween your specimens and the patterns in your note-book. Compare them freely with each other, and you will soon have many little collections of plants bearing very strong resemblances to each other.

Your thought will be something like this : While you are observing and describing a plant, you will ask your- self, " Have I ever before described one like this in the matters of cohesion and adhesion ? " If you can think of none, you will try to recall those nearest like it. By pur- suing this plan, you will be surprised to find how quickly many of the plants of a region, that were never before thought of as at all alike, fall into company on the ground of these deeper resemblances which your studies have led you to discover.

The reason why you are set systematically to classify- ing plants now, and have not been asked to do it before, is, that among the characters of plants that belong to roots, leaves, stems, etc., there are none that are so uniform throughout large numbers of different plants as these feat- ures of cohesion and adhesion in flowers. Since you be- gan to observe plants, you have not been taught to notice any points of structure that would serve so well for unit- ing plants into groups, the members of which are truly and somewhat nearly related to each other.

But the grounds on which you are to begin to classify plants, although important, and, in many cases, quite suffi- cient, are not the only ones on which classification is based. Though they may sometimes be found too narrow, yet you must begin somewhere, and to make your beginning as free as possible from complexities, you start with the feat- ures named in the flower-schedule. In working with this, much of your experience will be clear and satisfactory,

COMPARING AND CLASSIFYING PLANTS. ;9

but you may meet with difficulties. By-and-by, however, the subject will be resumed, and, if you have sometimes been confused and puzzled in classifying by the flower- schedule alone, new ideas will be all the more welcome.

Students who have the botanical charts will find them very helpful in the work of classification. Upon these charts there are pictured in the colors of Nature some forty pattern-plants, magnified, and shown in section, so that their structure is easily seen. These plants have been selected because the differences they present are just those broad contrasts that separate groups of plants in Nature. At this stage of your study, while your thoughts are con- fined to the features of the flower-schedule, the first, sec- ond, third, and fifth charts present plants of all varieties in these respects. Their great value lies in the distinct- ness of the idea they give as to how pattern-plants are constructed.

The work of classification being now entered upon, it will be resumed, from time to time, with further explana- tions as we proceed, particularly when we come to study such groups of plants as the grains and grasses, the cone- bearing plants, the Composite, familiarly known as com- pound flowers, the Umbelliferae, etc. These striking natu- ral orders will introduce us to new principles in judging of affinities, and pupils who are specially fond of this part of the study, and are apt in tracing resemblances, will do well to look over the chapters upon these plants without waiting to reach them in the course of regular study.

There is often, among both teachers and pupils, an aversion to skipping about. The idea of thoroughness with them seems to imply moving steadily on from page to page of a book, without ever deviating from its order. But in such a science as botany it is not necessary to pro- ceed in this way. The subject can not be marked off sharply into parts that must be learned in a certain order. Of course, plant-characters must be known before they

80 BOTANY.

can be used in classification ; but, when a few are known, they may be at once put to service. A pupil can not do better than to acquaint himself with the group of crucifer- ous plants as soon as the special characters that belong to this group are familiar. Any group of plants may be clas- sified as soon as the characters upon which it is founded are fairly known. To get a knowledge of classification requires much time, and its study should, therefore, be commenced at the earliest possible moment.

There is another reason for skipping about, which will be at once appreciated. It is this : Plants have their time to flower, and their flowers must be studied at that time. For example : the Coniferae blossom in spring, and spring is the time to study them. Stamens may be found through- out the entire season, and so may be studied at any time. It would be folly, therefore, to let the period pass in which the Coniferse might be studied, because you " hadn't come to them " in the book, and pursue the study of stamens because they are next in order. Again, the characters of orchids are illustrated by a plant which has its season, and the time to study orchids is when this plant makes its ap- pearance.

CHAPTER FIFTH.

THE MINUTE STUDY OF THE ESSENTIAL ORGANS OF PLANTS,

1

or Cell.

EXERCISE XXX. Parts of Stamens.

IN Fig. 219 you see the parts of a well-formed stamen. The ANTHER-LOBE is the cell which holds the pollen (Fig. 219). CONNECTIVE, a continuation of the filament which unites the two lobes of the an- ther. It is Often inCOnSpicUOUS [{ \- Connective.

or absent, but is sometimes easi- Anther

. Anther- __£•[ _JU._. Anther-Lobe,

ly seen (Fig. 219). VALVES, the Lobe- '' sides of an anther-lobe.

LINE OR POINT OF DEHIS- CENCE. — The opening through which the pollen escapes.

Do you see in your specimen FIG

a groove down the middle of the

anther on one of its sides ? Is there anything like a ridge on the other side of the anther, opposite the groove ? Can you divide the anther at this place without coming upon the pollen ? What name is given to this part of the anther in Fig. 219 ? What are the two halves it connects called ?

Look at your living anther for the line along each lobe, called the line of dehiscence.

It may help the learner in forming a distinct idea of these different parts of the anther, to know that the sta-

82

BOTANY.

men is looked upon by botanists as a sort of leaf, the fila- ment answering to the petiole, and the anther to the blade The connective corresponds to the midrib of a leaf, and the line of dehiscence to its margin, each lobe being half of a leaf-blade, and the valves of an anther corresponding to the upper and under sides of a leaf.

Examine the anthers of as many different flowers as possible, and try to find the cells, connective, line of dehis- cence, valves. Do not be disappointed or discouraged if, in many cases, you fail to distinguish some of the parts.

Gather flowers with large, perfect stamens, which have not shed their pollen, and compare them with Fig. 219.

Look at the magnified stamens on the charts, and find, if you can, the parts of the anther named in this exercise.

EXERCISE XXXI. Number and Shape of Anther-Lobes. An anther-lobe is said to be EMARGINATE when the summit, or base, of the anther-cell extends upward or downward, a little beyond the connective (Fig. 226).

NUMBER OF ANTHER-LOBES.

FIG. 220. One-celled Anther.

FIG. 221. Two-celled Anther.

FIG. 222. Four-celled Anther.

Label each flower of your collection with the number and shape of the anther-cells of its stamens.

THE ESSENTIAL ORGANS OF PLANTS. 83

SHAPE OF ANTHER-LOBES.

FIG. 225.

Kidney-shaped

Anther.

FIG. 227. Sinuous Anthers.

FIG. 224. Oblong Anthers.

FIG. 223.

Arro w-sh aped

Anther.

FIG. 226. Emarginate Anthers.

Find upon the charts one-celled anthers, two-celled anthers, four-celled anthers.

EXERCISE XXXII. Dehiscence of the Anther.

VERTICAL OR LONGITUDINAL DEHISCENCE. — When the anther opens by a slit along its length to emit the pol- len (Fig. 228).

TRANSVERSE. — When the line of dehiscence is across the anther (Fig. 229).

POROUS. — When the anthers emit the pollen through little pores (Fig. 230).

VALVULAR. — When a portion of the anther is lifted up to emit the pollen (Figs. 231 and 232).

What modes of dehiscence of anther-cells are shown upon the charts? In describing the stamens, name the kind of dehiscence the anther exhibits.

84

BOTANY.

FIG. 228. FIG, 229.

Vertical, Transverse, or Longi- tudinal.

FIG. 232, Valvular.

EXERCISE XXXIII. Introrse and Extrorse Anthers.

The projecting side of the anther-cell is called its face, and the opposite side its back, whether the valves are un- equal or not.

When the valves of the anther are of equal size, the dehiscence will occur laterally (Fig. 235) ; but, if one valve be wider than the other, it will throw the line of dehiscence

FIG. 233.— Face.

FIG. 234.— Back.

FIG. 235. — Lateral Dehiscence.

nearer to the connective on one side than on the other. These narrowed valves are usually on the face or project- ing side of the anther-cell (Fig. 233).

THE ESSENTIAL ORGANS OF PLANTS. 85

It is on the other side that the connective is usually visible, if seen at all, and that the filament is in most cases attached (Fig. 234).

FIG. 236. — Introrse Anthers.

Facing the Corolla.

FIG. 237. FIG. 238.

Extrorse Anthers. Extrorse Anthers.

Anthers are INTRORSE when the line of dehiscence, or face of the anther, is toward the pistil (Fig. 236).

Anthers are EXTRORSE when the line of dehiscence, or face of the anther, is turned toward the corolla (Figs. 237 and 238).

Look over the charts for examples of extrorse and introrse anthers. Observe this feature when you study flowers.

EXERCISE XXXIV. Attachment of Filament to Anther.

INNATE. — Anthers are innate, or basifixed, when the fila- >nt runs directly into the base of the connective (Figs. 239, 240, and 244).

ADNATE. — Anthers are adnate, or dorsifixed, when the filament runs up the back of the anther, joining the con- nective in such a way that the anther is hung in front of it (Figs. 241 and 242).

VERSATILE. — If the filament is attached by a slender apex to the middle of the anther, the ends of which swing

86

BOTANY.

freely up and down, the attachment is said to be versatile (Fig. 243).

The modes of attachment, pictured and named above,

FIG. 239. — Innate.

shade into each other, so that, in practice, it is often diffi- cult to determine them. The versatile passes into the ad-

FIG. 244. Basifixed.

FIG. 245. Dorsifixed.

FIG. 246. Apsifixed.

FIG. 243. — Versatile.

nate, and the adnate into the innate, and a nice exercise of judgment is sometimes needed in describing this feature of flowers.

THE ESSENTIAL ORGANS OF PLANTS. 87

Find these several modes of attachment on the charts. Determine and describe the mode of attachment in each of your living specimens.

EXERCISE XXXV. .Forms of Filaments.

FILIFORM filaments are thread-like, as the name de- notes, but strong enough to support the anther (Fig.

239)-

SUBULATE filaments taper like an awl (Fig. 247).

CAPILLARY filaments are hair-like, and too slender to support the anther (Fig. 248).

DILATED filaments are flattened out like Fig. 249.

PETALOID filaments resemble petals in form, and bear the anther at the summit, as seen in Figs. 250 and 251.

FIG. 247. Subulate.

FIG. 248, Capillary

FIG. 249. Dilated.

FIG. 253. Bidentate.

BIDENTATE, or BICUSPID, filaments are toothed at the summit or at the base, as seen in Figs. 252 and 253.

Find examples of the several kinds of filaments upon the charts. Describe the different forms of filaments in your collection of plants.

88

BOTANY.

EXERCISE XXXVI. Structure and Forms of Pollen.

The pollen-grain is generally composed of two mem- branes, or coats, filled with a thick liquid substance con- taining minute grains, which is its essential portion. The outer coat is frequently marked with bands, lines, and

FIG.

FIG. 255.

FIG. 256.

grooves, or covered with bristling points (Fig. 254). The inner coat is very thin, and swells when wet. If you moisten pollen-grains, you may often see, with a micro- scope, the expanded inner coat protruding through open- ings in the outer coat.

EXTINE. — The outer coat of a pollen-grain, usually with openings, or very thin in certain places (Figs. 254 and 255).

- Fovilla.

Intine

Exline.

FIG. 257.

FIG. 258.— Pollinia.

FIG. 260.

INTINE. — The inner coat of a pollen-grain, very thin, tough, and elastic, often seen protruding through holes in the extine (Figs. 255 and 256).

THE ESSENTIAL ORGANS OF PLANTS. 89

FOVILLA. — The rich protoplasmic liquid contained within the intine (Fig. 257).

POLLINIA. — Pollen-grains cohering in masses. In Fig. 258 they are in pairs, and are furnished with stalk-like processes ; but in some plants they are single, and without a stalk.

Pollen-grains display a great variety of shapes. Besides the round and oblong (Figs. 259 and 260), you will find them angular, lobed, and joined together in various ways (compound pollen) by threes, fours, and even larger num- bers.

Look at the various forms of pollen pictured upon the charts.

Examine the pollen of flowers with your magnifying- glass, and note the shape of the grains, and the kind of surface they present. Observe the moistened pollen of various plants under the microscope.

EXERCISE XXXVII. Forms of Connective.

APPENDICULAR. — When the connective, ex- tending above or below the anther, takes the form of a feather, or a lengthened point, or

FIG. 261. FIG. 262. FIG. 263. Appendicular.

FIG. 264. FIG. 265. Connective, widened.

9o

BOTANY.

a fleshy mass, or spur-like appendages, or stipules (Figs. 261, 262, and 263), it is said to be appendicular.

When one lobe of an anther is abortive, or suppressed, the anther is said to be dimidiate. Fig. 266 represents a dimidiate anther and a connective developed into arms, so that the lobes are entirely disconnected.

Observe the abortive anther-lobe of Fig. 266. The entire stamen, as well as each of its parts, is liable

to suppression, abortion,

Anther jj or imperfect development.

The symmetry of flow- ers is often destroyed in f.. — connective, this way. In some plants the non - development of organs that exist in the ru- -Fiiament. dimentary state is a con- stant character, and should be regarded in describing

FIG. 266.— Dimidiate.

them.

Observe the figures on the chart which illustrate these forms of connective. Look over the flowers of your col- lections, and in future describe the form of connective when you can distinguish it.

EXERCISE XXXVIII. General Features of Stamens.

EXSERTED. — Stamens are said to be exserted when they extend beyond the corolla (Fig. 267).

INCLUDED. — When the stamens are not as long as the corolla, they are said to be included (Fig. 268).

The entire whorl of stamens is called the andrcecium.

When the filament is wanting, the anther is described as sessile.

When the anther is wanting, the stamen is said to be sterile.

THE ESSENTIAL ORGANS OF PLANTS.

91

FIG. 268.

Converging stamens are said to be connivent.

In observing and describing sta- FIG. 267. mens, the following questions will be

found useful by calling attention to the several characters pointed out in the present chap- ter :

Parts ? Number of anther-lobes ? Shape of anther- lobes ? Attachment of filament and anther? Facing?

Form of filament ? Form of pollen ? ive ? General features.

Form of connect-

CHAPTER SIXTH.

THE PISTIL.

EXERCISE XXXIX. Kinds of Style and Stigma.

FIG. 273.— Trifid.

FIG. 270. Sessile and Lateral. FIG. 271.— Bifid. FIG. 272.— Tiifid.

FIG. 276,

Lobsd. FIG. 274.— Scrolled FIG. 275.— GLbosa.

NAME the kinds of stigma shown on the chart.

THE PISTIL.

93

EXERCISE XL. Form and Position of Style

FIG. 277. Sigmoid.

FIG. 278. Lateral.

FIG. 279. Basal.

FIG. 280. Terminal.

The shapes of styles may be named by the same words as the shapes of filaments.

Observe, in faded flowers and young fruit, whether the styles are persistent or deciduous.

EXERCISE XLI. Pistil, Ovary, Fruit.

It will be convenient to apply the following names to certain distinctions among pistils with which pupils are now familiar :

A COMPOUND PISTIL (Fig. 281) consists of several united carpels — is syncarpous.

FIG. 281. A Compound Pistil.

FIG. 282. A Simple Pistil.

A SIMPLE PISTIL (Fig. 282) consists of only a single carpel, and is, of course, apocarpous.

94

BOTANY.

FIG. 283. Multiple Pistil.

FIG. 284. Multiple Pistil.

A MULTIPLE PISTIL (Figs. 283 and 284) consists of several distinct carpels — is also apocarpous.

Pluck from the pea or bean vine pods of different ages and com- pare them. The soft, small bodies in the young pods are called ovules. The ripe, full-grown con- tents of the mature pod are seeds. Pod and con- tents form the fruit. The fruit of a plant is its rip- ened ovary. Find the ovules of unripe apples,

tomatoes, cucumbers, etc. Count the carpels in all the ovaries you examine.

Look among dry pea or bean pods for those that have begun to open. Examine the edges of the separate parts.

DEHIS'CENCE is the self-opening of an ovary at ma- turity.

A SUTURE is the line along which dehiscence occurs (Figs. 31.7, 319).

VENTRAL SUTURE — the inner suture of a carpel looking toward the center of the flower. In the pea and bean it is the suture along which the ovules are attached (Fig. 314).

DORSAL SUTURE — the outer suture. Besides dehiscent ovaries, which open of themselves, find indehiscent ones.

DISSEP'IMENTS— the partitions between the cells of syn- carpous ovaries (Figs. 291-318).

PARIETES — the walls of the ovary. Axis — the central part of an ovary. In compound ovaries it is where the ventral sutures join together. Find the axis in Figs. 291-318.

THE PISTIL. 95

VALVES — the parts into which carpels separate by de- hiscence (Fig. 319).

PLACENTA — the cord along the ventral suture to which ovules are attached.

Point out and name the various kinds of pistil shown upon the charts.

EXERCISE XLII. The Structure of Ovaries.

Whether a pistil is simple, multiple, or compound, each carpel may be looked upon as a single leaf. The simple pistil of the pea, for instance, may be regarded as the blade of a leaf folded at the midrib, so that its inner por- tion answers to the upper face of a leaf, and its outer por- tion to the under face. Its dorsal suture will correspond to the midrib, and its ventral suture to the margin of the leaf.

To make this plainer, take any strong oblong leaf (Fig. 285), and fashion it into a carpel, like the pea-pod, taking the upper part of the leaf for the inner part of the carpel. Fold in the margins slightly to represent the placentae (Fig. 286). If the fold will not stay in place, take a stitch or two along it with a needle and thread. Now fold it together at the midrib (Fig. 287), and compare it with a pea-pod. Find the valves ; the dorsal and ventral por- tions ; the stigma ; the base.

Gather old, faded pea-blossoms, in which the ovary is somewhat enlarged, and observe that the ventral suture is turned inward ; that is, it lies along the central line, or axis, of the flower. It is along this axis, then, that the double placentas are formed. Observe the position of the dorsal suture, or back of the pod. It is important to bear in mind that, in the case of the simple pistil, the ovules are attached centrally along the axis of the flower.

Roughly to imitate a multiple pistil, you have only to bind together, by their petioles, several leaf-blades that 6

90

BOTANY.

have been converted into carpels, as above. Observe the placentation of any multiple pistil, and you will invariably find that the placenta of each carpel is central in the same way that, in the artificial one, you have made the margins of your carpellary leaves turn inward, and the midribs outward.

After thus preparing simple and multiple pistils from foliage leaves, let us try to construct a compound pistil from leaf-blades. If we can do this, it will give us a clear understanding of the structure of syncarpous ovaries.

Form, from foliage leaves, an artificial ovary of three coherent carpels. A three-celled compound pistil consists

FIG. 285.

FIG. 286.

FIG. 287.

of three carpellary leaves grown together. It is as if, by pressing together the carpels of your multiple pistil, they should unite by their sides. To make an artificial com- pound pistil, then, you have only to select three large, sym- metrical foliage leaves, and pin or stitch them together in such a way that their margins will meet in the center, and their under surfaces will form its outer wall. If you can

THE PISTIL.

97

not get leaves of firm texture that will hold a pin or a stitch without tearing, try lining them with some thin cloth or paper. Fold each of the leaves at the midrib, with the upper surface inward, as seen in Fig. 288. Fasten the left half of one leaf-blade to the right half of another, so that

FIG. 289.

FIG. 288.

the united portions will form a double wall between the cells, and the six edges will meet together at the center, as represented in Fig. 289.

Your aim being simply to understand how, and from what, each part of a compound pistil is formed, you need not care for the clumsiness or shapelessness of your manu- factured ovary.

Point out its cells. Its dissepiments. Explain why they are double. Point out the dorsal and ventral suture of each carpel of your syncarpous structure. Where should you look for ovules in this pistil ?

Prepare a compound ovary by joining three leaves at their margins, as seen in Fig. 290. In what part of an ovary so formed are the leaf-margins ? In what part of the ovary would you look for the ovules ? The theory that the pistils are made from leaves is important, because

98

BOTANY.

it gives clear ideas of the varied and complex characters of ovaries ; and these characters are of the greatest value in classification.

EXERCISE XLIII. Placentation.

After studying the structure of ovaries, as explained in Ex. XLII, the following definitions will be easily un- derstood :

PLACENTATION. — The arrangement of placentas is called placentation.

To determine the mode of placentation of a plant, slice its ovary across, and compare its appearance with the

FIG. 291.

FIG. 292.

FIG. 293.

FIG. 294.

following figures. The formation and arrangement of pla- centae are so various, that we have given an unusual num- ber of drawings to illustrate the definitions.

FIG. 296. FIG. 295.

AXILLARY PLACENTATION. — When the ovules are found along the central line, or axis of the pistil, the pla-

THE PISTIL.

99

centation is called axillary, or axile (Figs. 291, 292, 293, 294, 295).

FREE-CENTRAL PLACENTATION. — When the dissepi- ments, or double partitions between the cells, are absent, leaving the placentae and ovules at the center, and all the

FIG. 300.

FIG. 299.

FIG. 298.

FIG. 302.

FIG. 301.

cells opening into one chamber, the placentation is said to \>z free-central (Figs. 296, 297, 298, 299).

PARIETAL PLACENTATION is seen when the placentae are attached to the walls, or projections from the walls, of the ovary, as is illustrated in Figs. 300-307.

FIG. 303.

FIG. 304.

FIG. 305.

FIG. 306.

FALSE DISSEPIMENTS. — It will be well to know that, in many ovaries, there are partitions not formed in the way described in Ex. XLII. The following are instances of what are known as false dissepiments :

Observe in Fig. 308 a partition going inward from the

100 BOTANY.

dorsal suture, and nearly reaching the center of the seed- vessel.

Fig. 309 shows a similar false partition not quite so much extended.

Fig. 310 is a section across the middle of an ovary, and Fig. 311 is a section across the upper part of the same

FIG. 307. FIG. 308. FIG. 309.

ovary. The partitions that appear in one and are not seen in the other must be false — they can not be formed by the sides of adjacent carpels.

In Fig. 312 the placentae are parietal, but a membrane is formed, reaching across the ovary, and forming a false

FIG. 310. FIG. 311. FIG. 312.

dissepiment. These false dissepiments, you see, are de- veloped, in some cases, from the dorsal suture ; in others, from the placentae.

It may sometimes be difficult to decide between true and false dissepiments ; but, as your knowledge of plants

THE PISTIL.

IOI

increases, the different members of the same group will often be found to afford transitional characters that make evident what otherwise would be uncertain.

Observe and name all the forms of placentae seen upon the charts.

EXERCISE XLIV. Modes of Dehiscence.

To understand the modes of dehiscence pictured in this exercise, you have only to prepare a three-celled com- pound ovary, as directed in Ex. XLII, observing the place of the dorsal and ventral sutures, the relations of the valves, and that the partitions are double.

REGULAR OR VALVULAR DEHISCENCE occurs when the ovary separates into the regular pieces called valves.

Dehiscence is SEPTICIDAL when the ovary splits through the partitions, each dissepiment separating into its two layers, one belonging to each carpel (Figs. 313, 314, and 315),

Dehiscence is LOCULICIDAL when the splitting opens into the cells by the dorsal suture, as seen in the dia-

FIG. 313.

FIG. 314.

FIG. 315.

gram 316 and in Fig. 317, which represents the ovary of a violet, where the carpels flatten out as soon as they are released from each other.

102

BOTANY.

Dehiscence is SEPTIFRAGAL where the valves fall away, leaving the dissepiments behind attached to the axis (Figs. 318 and 319).

FIG. 316.

FIG. 317.

FIG. 318.

IRREGULAR DEHISCENCE. — Seeds are sometimes dis- charged through chinks, or pores (porous dehiscence) (Fig. 320), or the ovary may burst in some part irregularly. Name the modes of dehiscence given on the charts.

Now compare the capsules in your collec- tion with the figures and definitions given in this exercise, and deter-

FlG.

319-

FIG.

mine, if you can, the mode of dehiscence of each of them.

How would you produce loculicidal dehiscence in the compound ovary you have made with leaves, as directed in the opening of this exercise ?

How septicidal ? How septifragal ?

THE PISTIL.

103

EXERCISE XLV. Direction of Ovules and Seeds.

Ovules have a horizontal direction when they are nei- ther turned upward nor downward, as in Figs. 321 and 322.

They are ascending when rising obliquely upward, as in Fig. 323.

Ovules are said to be

^

FIG. 321.

FIG. 322.

erect when rising upright from the base of the cell (Fig. 324). They are suspended when hanging perpendicularly

FIG.

FIG. 326.

from the summit of the cell (Fig. 325). They are /<?#iwhen hanging from near the top (Fig. 326).

Find examples of ovules having different directions in the magnified ovaries upon the charts.

104

BOTANY.

EXERCISE XLVI. Parts of the Ovule.

FIG. 327.— Growth of Ovule of Celandine. — a. Nucleus, b. First-formed covering: c. Second covering, d. Funiculus, very greatly enlarged, e. Base of Ovule.

BASE OF OVULE. — The little stem of an ovule — the funiculus — has two points of attachment, one to the ovule and the other to the placentae. Now, the base of the ovule is at the point where it is attached to the funiculus, and not at the point where the funiculus is attached to the placentae.

APEX. — The apex of the ovule is opposite to the base.

PRIMINE. — The outer covering of the ovule — seen at b, Fig. 327.

SECUNDINE. — The inner covering of the ovule — c, Fig. 327.

NUCLEUS. — The substance writhin the coverings — a, Fig. 327.

RHAPHE. — The connection between the base of the nucleus and the base of the ovule. This is shown in Fig. 328 by the fine, irregular lines representing tissue and connecting the base of the nucleus with the base of the ovule. The opening in the coats of an ovule or seed. In Fig. 328 the micropyle is shown at the top of the ovule.

CHALAZA. — The place where the coats and nucleus grow together. In Fig. 328 it can not be distinguished from the rhaphe.

FIG. 328. — Section of the Ovule of Pelar- gonium before fer- tilization. (Magni- fied.)

MICROPYLE.-

THE PISTIL. 105

HILUM. — The scar left by the separation of a seed from its placenta.

It is not supposed that pupils will find all these parts of the ovule in plants. Some of them are usually discern- ible, and they may all be understood in their proper rela- tions by studying the diagrams.

EXERCISE XLVIL Kinds of Ovule.

The STRAIGHT, or ORTHOTROPOUS OVULE, has the base of the nucleus and the base of the ovule in the same position, while the micropyle is at the apex (Fig. 329).

Micropyle-

Hilumand %^» Chalaza._JS«gf HB*-- MLropyle. Chalaza— -^^

FIG. 329. FIG. 330.

Straight, or Orthotropous. Curved, or Campylotropous.

In the CURVED, or CAMPYLOTROPOUS OVULE, the mi- cropyle, or apex, is bent over close to the base (Fig. 330).

In the INVERTED, or ANATROPOUS OVULE, the funicu- lus lengthens, and bends round, growing fast to the coat,

RhaPhe--i • mm I. ^1-Micropyle.

ChalaZa.___^||f __._ Micropyle. Rhaphe '* >^~

FIG. 331- FIG. 332.

Inverted, or Anatropous. Half-inverted, or Amphitropous.

until the base of the nucleus is at the apex of the ovule (Fig. 33i).

In the HALF-INVERTED, or AMPHITROPOUS OVULE, the funiculus only lengthens till the ovule turns a quarter of the way over, as in Fig. 332.

106 BOTANY.

In describing the pistil of flowers, answer the follow- ing questions: What is the form and position of the stig- ma ? Of the style ? Is the pistil simple or compound ? What is its placentation ? Its dehiscence ? What is the direction of the ovules ? Can you determine the kind of ovule ?

EXERCISE XLVIII. The Composition of Fruit.

FRUIT. — The ripened ovary, with its contents, is the fruit of plants. Whatever adheres to the ovary also be- comes part of the fruit.

In studying fruit, observe with care what parts, be- sides the pistil, have been concerned in its formation. In describing flowers, you note whether the pistil is inferior or superior ; is there any reason to suppose that inferior fruit would be most likely to have other parts of the flower besides the pistil united with it ? Did you observe the flowers of the cherry, plum, or peach trees, and those of apple and pear trees when they were in blossom ? and if so, will you compare your recollection of them with the appearances presented by their fruit ? If you have for- gotten their structure, perhaps you have kept a descrip- tion of them, and can refresh your memory.

Observe the ripe fruit of the cherry. Look at the top of the peduncle for scars left by the parts of the fallen flower. Look for a dot at the top of the fruit, showing the place of the style. Has anything but the pistil en- tered into the formation of this fruit ? Observe the plum, peach, grape, currant, etc., and see if they are like the cherry in these respects.

Now examine an apple or pear. What do you find at the top of the fruit, opposite the peduncle ? It must be the remains of the calyx-limb, the tube of which you saw united to the pistil when you studied it in flowering-time. Of what, then, does the fruit consist ? Divide an apple or

THE PISTIL. 107

pear, as shown in Fig. 333. Find the parts shown in this

diagram. The remains of the flower are seen at C. The

calyx-tube, grown fleshy and

succulent, is marked T. The

outer border of the ovary is

seen at E. From what part of

the flower is the eatable portion

of a pear or apple developed?

To repeat our former question,

would the fruit of a superior

pistil be more likely than that

of an inferior pistil to consist

o'f the ovary alone ?

I have illustrated the composition of fruit with apples and cherries because they are so common ; but these ob- servations may, and should be, repeated upon every vari- ety of fruit that can be found.

Trace the formation of each of the fruits pictured upon the charts, and point out those that consist of the pistil alone, and those which do not. In the latter case, name the parts that are consolidated with the pistil in the fruit.

When fruit is formed from the pistil alone, the wall of the ovary is called a pericarp (from/m, around).

Gather specimens of every kind of fruit that grows within reach. In late summer or early autumn, the fruit of garden, field, and forest, if carefully, collected, will give you a large and various assortment. For example : you may have at the same time cucumbers, melons, beans, peas, grapes, apples, pears, elder and pokeweed berries, chest- nuts, walnuts, pumpkins, etc., and the less conspicuous seed-vessels of mullein, Saint-John's-wort, lettuce, radish, cabbage, etc., etc. Earlier in the season the list will be dif- ferent, and it will vary somewhat with the locality, but, wherever collected, and whatever its components, be sure to gather every kind that can be had.

Look over your collection, and separate the superior

I08 BOTANY.

from the inferior fruits. Observe the structure of those formed from inferior pistils, and point out the pericarp in those formed from superior pistils.

Preserve, for further study, the specimens you have gathered.

EXERCISE XLIX. Parts of the Pericarp.

EPICARP. — When the walls of a pericarp are formed of two or more layers of different texture, as in the peach, plum, or cherry, the outer one (the skin, in the case of these fruits) is called the epicarp.

ENDOCARP. — The stony case around the seed of the peach, plum, or cherry, is called the endocarp. But the en- docarp of fruits is not always stony. Whatever its texture, the inner layer of a pericarp is named the endocarp. MESOCARP. — Sometimes, between FIG. 334. the outer and inner parts of a peri-

carp, there is found a third layer of different aspect, like the pulp of a peach. This third layer is called the mesocarp. The distinction between the epi- carp and mesocarp is often very, slight, and then both to- gether are called the epicarp.

In Fig. 334, e is the endocarp, s the mesocarp, and g the epicarp.

In Fig. 333, E is the epicarp, N the endocarp, and S the seeds. At N is shown a slight development of the mesocarp. Point out these parts in an apple and a peach. Point out the parts of the pericarp in the different fruits pictured upon the charts.

Classify your collection of fruits by the structure of the pericarp. Put by themselves all those that have but one layer in the pericarp. Put those with two layers— an epicarp and endocarp— by themselves, leaving those with

THE PISTIL.

109

three layers — epicarp, mesocarp, and endocarp. Describe the layers that make up the fruit ; that is, sayVhether, in each case, the layer is pulpy, woody, stony, membranous, leathery, etc.

Preserve your collection for further study, and add to it all you can get.

EXERCISE L. The Classification of Fruit.

Look over your collection and separate the dehiscent from the indehiscent fruits. The indehiscent group may now be further separated into juicy fruits and dry fruits. Compare your specimens of juicy fruit, one by one, with the following pictures and definitions of fruits. The first picture is that of a berry ; so you may first find the berries of your collection. To determine whether a particular fruit is a berry or not, cut it across, and see if it agrees in structure with Fig. 335, and the requirements of the defi- nition. Never mind whether your conclusion accords with common speech or not ; whether a strawberry turns out to be a berry or not; but follow the definition wherever it leads.

Indehiscent Juicy Fruits.

BERRY. — A thin-skinned, indehiscent, fleshy fruit, hav- ing the seeds imbedded in the pulpy mass (Figs. 335. 336).

FIG. 335. FIG. 336.

HESPERIDIUM. — A kind of berry with a leathery rind (Fig. 337). (Example, lemon and orange.)

no

BOTANY.

PEPO. — The pepo is an indehiscent, fleshy fruit, with seeds borne on parietal placentae, and with the epicarp

more or less thickened and hardened. (Example, squash.) POME is the term applied to a fleshy, indehiscent, sev- eral-celled fruit, with a leath- ery, or cartilaginous, endocarp, inclosed by the calyx-tube. Figs. 338 and 339 are trans- verse and vertical sections of a pome. (Example, apple and

FIG. 337- Pear')

N

\

1

FIG. 338.

FIG. 339.

FIG. 340.

DRUPE (example, peach or cherry) is a pulpy, indehiscent, one-celled, one or two seeded fruit, with a succulent or fibrous epicarp, and hard, stony, dis- tinct endocarp (Figs. 340 and

If you have blackberries, raspberries, and the like, among your fruits, compare one of the FlG 341>

little cells of which they are

formed with this definition of a drupe. To one or other of these classes vou should be able to refer any form of indehiscent juicy fruit.

THE PISTIL. Ill

Indehiscent Dry Fruits.

Select from among your dry, indehiscent fruits all those that resemble Figs. 342, 343, 344, and 345, and that are usually miscalled seeds. You will find upon many of them such appendages as hairs, teeth, plumes, bristles, etc.

An ACHENIUM is a dry, indehiscent, one-seeded fruit,

FIG. 342. Vertical Sec- tion of Carpel of Buttercun.

FIG. 343.

3.5.

with a separable pericarp, tipped with the remains of the style (Fig. 342). (The dark-colored, seed-like bodies on the outside of a strawberry are achenia.)

UTRICLE. — By this term is understood a kind of ache- nium, with a thin, bladdery pericarp which is sometimes dehiscent.

CARYOPSIS. — A dry, indehiscent, one-celled, one-seed- ed fruit, with the pericarp adherent to the seed, as seen in wheat, barley, oats, maize, etc. (Fig. 345).

CREMOCARP. — Pendent achenia (Fig. 344). (See Ex. LXVI.)

CYPSELA. — Still another variety of achenium, with an adherent calyx-tube, as in compositae (Fig. 343).

NUT. — A hard, one-celled, one-seeded, indehiscent fruit, produced from a several-celled ovary, in which the cells have been obliterated, and all but one of the ovules

I 12

BOTANY.

have disappeared during growth. It is often inclosed in an involucre, called a cupule (Fig. 346), or it has bracts at the base.

FIG. 346.

FIG. 347.

SAMARA, or KEY-FRUIT (example, the elm). — A dry, indehiscent fruit, growing single or in pairs, with a winged apex, or margin (Fig. 347).

Dehiscent Fruits.

Any dry, dehiscent fruit, whether simple or compound, may properly be called a pod. FOLLICLE. — A pod of a single carpel, with no apparent dorsal suture, and dehis- cing by the ventral suture (Fig. 283). You will seldom find an

FIG. 349.

FIG. 348.

FIG. 350.

FIG. 351.

ovary consisting of but one follicle ; but it is a common kind of carpel in multiple pistils. Observe the ripe ovary

THE PISTIL.

FIG.

353-

FIG. 352.

of columbine or paeonia. Each car- pel is a follicle, and you may find them slightly coherent at the base, as if forming a transition between the apocarpous and syncarpous pistil.

LEGUME. — A pod of a single carpel, with dorsal and ventral sutures, and dehiscing by both or either, as the pea and bean pod. It assumes many different forms.

One of these, the LOMENT, is a sort of legume with transverse joints between the seeds, and falling to pieces at these joints (Fig. 348).

Another variety, the SILIQUE, is a two-valved, slender pod, with a false dissepiment, from which the valves sep- arate in dehiscence. It has two parietal placentae (Fig.

349)-

SILICLE. — A short, broad silique (Fig. 350).

PYXIS. — A pod which dehisces by the falling off of a sort of lid (Fig. 351).

CAPSULE. — The pod of a compound pistil ; the dry, dehiscent fruit of syncarpous pistils (Figs. 352 and 353). The pieces into which a capsule falls at dehiscence are called valves, the same as in one-carpeled fruit.

Those fruits that consist of achenia on a dry recepta- cle, as the sunflower, or on an enlarged, pulpy receptacle, as the strawberry, or those which consist of small drupes

114

BOTANY.

on a dry, spongy receptacle, crowded almost into one mass, as the blackberry, are aggregate fruits. They are sometimes called etario.

Accessory, or anthocarpous fruits, are such as consist of other parts of the flower only apparently joined with the ovary.

MULTIPLE, COLLECTIVE, or CONFLUENT FRUITS, are formed by the union of many separate flowers into one mass (Figs. 354 and 355),

The sorosis is a kind of multiple fruit, to which the

• 354-

FIG. 355.

pineapple (Fig. 354) belongs. The fig is a multiple fruit of the kind known as syconus, while strobilus is the name given to the multiple fruit of trees of the pine family (Fig.

355)-

EXERCISE LI.

The Seed.— Its Form and Surface.

The forms of seeds vary very much. They may be globular, ovoid, reniform, oblong, cylindrical, top-shaped, angular, etc. Some seeds are small and fine, like sawdust; others are flattened and bordered, as seen in Fig. 356.

THE PISTIL. 115

The surfaces of seeds may be smooth, striated, ribbed, furrowed, netted, and tubercular, as shown in the follow- ing figures :

Seeds are said to be definite when few and constant in number ; indefinite when numerous and variable.

FIG. 359. Ribbed.

FIG. 360.

Netted.

FIG. 361. Tuberculous.

FIG. 362. Furrowed.

Seeds are solitary when single in the ovary, or in a cell of the ovary.

The albumen of seeds is the mass of tissue in which the embryo is imbedded. It is said to be mealy when it may be readily broken down into a starchy powder ; oily, when loaded with oil ; mucilaginous, when tough, swelling up readily in water ; and horny , when hard, and more or less elastic.

EXERCISE LII. Parts of the Seed.

Prepare for the study of the parts of seeds by planting all the kinds of seeds that you can get that are large enough for easy examination.

The seeds of the pumpkin, squash, four-o'clock, bean, pea, apple, Indian corn, oats, and barley, are good exam-

Ii6 BOTANY.

pies for the purpose. Plant two or three dozens of each sort, one inch deep, in a box of soil or sawdust, which must be kept warm and moist. Put the different kinds in rows by themselves, and mark each row, so that, when you want any particular one, you can get it without mistake.

When your seeds have soaked for a day or two in the wet earth, take a bean from the box and compare it with one that has not been planted.

How has it changed in appearance ?

Cut it in two and see whether, like a piece of chalk, it looks alike outside and inside, or whether the parts are unlike.

Has it a skin or shell that you can loosen ?

Take a second bean from the box, cut carefully around it, and try to peel off the outer part.

SEED-COAT, OR INTEG'UMENT. — The skin or shell around the outside of a seed.

BODY, KERNEL, OR NU'CLEUS. — The substance within the seed-coat.

Compare your specimen with Fig. 363.

Body.

FIG. 363.

Can you separate the seed-coat from the body of the bean as it is seen to be separated in the picture ?

Now take a pea from your box and see if it is made up of parts.

Has it a seed-coat ? Is there a kernel or body within the seed-coat ?

Try a pumpkin-seed. Compare the coat of a pump- kin-seed with that of the pea or bean.

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117

Are they alike in thickness ? in hardness ? in color ? in transparency ? Name all the differences you see be- tween them.

In the same way, take up and examine, one after an- other, seeds from each of the rows. Find their parts, and compare the parts of one kind of seed with those of an- other kind.

If you are not able at first readily to separate a seed into distinct portions, do not hastily conclude that it is without them. Let it lie in its warm, wet bed a while longer, and then try again.

EXERCISE LIII. Parts of the Body, or Kernel.

When you have carefully examined all the kinds of seeds you planted to find the parts that make them up, you will be ready to study one of these parts by itself. After

FIG. 364. FIG. 365. FIG. 366.

Albumen. Embryo. Embryo.

taking off the skin or coat of a seed, look closely at the body of it. Begin with a well-soaked seed of Indian corn.

Compare it with Fig. 364.

Is your seed narrower at one end than the other ? Are the two sides of it alike ? Is there a little pointed or rounded figure to be seen on one side ?

Remove the skin and look carefully at the figured side of your specimen. Can you see a thick, lumpy body like the one marked a in the picture ?

Try, with a dull knife or the finger-nail, to pry this lump out of its bed. If the seed is soaked to its center.

BOTANY.

you can easily do this. Look carefully at the hole it leaves. Is not its surface smooth ? Do you see any spot where the lump seems to have been grown to the other part, and to have broken away when you took it out ?

Compare the parts you have got with Figs. 365, 366.

EM'BRYO. — The young plant contained in a seed.

ALBU'MEN, EN'DOSPERM. — The material in which the embryo is imbedded.

What names are given to the two parts of the body of a seed of Indian corn ?

Which is the embryo in your specimen ? Which is the albumen ?

Now examine the kernel of a pea or bean. Can you separate this into two parts without breaking it some- where ?

Compare it with the parts of Indian corn.

What name is given to the entire kernel ? What part, found in the Indian corn, is missing here ?

FIG. 367.

FIG. 368.

FIG. 369.

FIG. 370.

Look at the body of a seed of four-o'clock and see how many and what parts it has. Look also at the body of a pumpkin-seed.

Examine the kernel of each of the kinds of seed you have planted, and observe which consist of em- bryo alone, and which are part embryo and part albumen.

ALBUMINOUS SEEDS are those which have albumen.

EXALBUMINOUS SEEDS are those in which the body consists of the embryo alone.

The relations of embryo to albumen in various seeds

THE PISTIL.

are here shown. But they may be better seen upon the charts. Your own observation, however, will supply you with much information upon this subject.

EXERCISE LIV. Parts of the Embryo.

Take out of the soil a bean which has begun to sprout. Remove the seed-coat, and let the parts of the embryo separate, as seen in Figs. 371 and 373.

COTYLE'DON. — The bulky first leaf or leaves of the embryo — more or less formed before the growth of the seed begins.

RAD'ICLE. — The lower, or root end, of the embryo.

PLU'MULE. — The first — the terminal bud — the upper end of the embryo.

GERMINATION. — The beginning of growth in a seed.

Read the names of the parts of the embryo given in

Plumule.

Cotyledon'

''Cotyledon.

Radicle. Plumule.

FIG. 372.

Cotyledon.

Plumule.

Radicle.

FIG. 373.

FIG. 374.

Figs- 372 and 373. Look at the definitions of these words. Compare your specimen with the figures, and point out its cotyledons ; its radicle ; its plumule. Handle your em-

7

120 BOTANY.

bryo with care, for it breaks easily. Has its radicle begun to put forth roots ?

Take from your box a vigorous seed of Indian corn in which the roots have begun to grow, and compare it with Fig. 374-

Separate the embryo and albumen, and, if it has grown as much as the one pictured above, you may easily find the cotyledon, the plumule, and the radicle.

When you are sure that you have found the radicle or root-end of your embryo, that you know which part is cotyledon, and which plumule, take another seed of the

same kind, but less grown — one plui?ule- where the root-end of the em-

bryo has scarcely begun to swell — and see if you can find the

Cotyledon. | Jll SM Plumule.

Radicie....™lf Fig. 375 represents such an

FIG. 375. embryo with the parts shown.

Point out and name the parts

of the embryo of an apple-seed; of a pumpkin-seed; and of each of your specimens successively, as in former exer- cises. Which of your seeds has the largest plumule before growth begins ? Have you any in which the embryo has at first no plumule at all ?

Have you failed to find cotyledons in any embryo looked at?*

* If these experiments with seeds are made as early as April, in this climate, the children who have made them will be ready for more extended observations when planting in the garden begins. Most garden-seeds are too small to be separated into parts by young chil- dren. But, when growth begins, their parts enlarge, and a child, who has before studied larger seeds, will be able to identify the radicle, cotyledons, and plumule, without difficulty. In the kitchen-garden, a universal appendage of country-houses, the sprouting of the radish, onion, beet, parsnip, lettuce, tomato, carrot, cabbage, cucumber, etc., will furnish an excellent continuation of the study of seeds.

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121

EXERCISE LV. Monocotyledons and Dicotyledons.

A MONOCOTYLED'ONOUS embryo has one cotyledon or seed-leaf (Fig. 376).

A DICOTYLED'ONOUS embryo has two cotyledons or seed-leaves (Fig. 377).

These are long, hard words, hard to pronounce and hard to spell. But they are very necessary words in de- scribing seeds.

Go over the seeds you have planted, and point out the dicotyledons. Find the two thick leaves that were packed within the seed-coat when the seed ripened.

Are any of your seeds monocotyledonous ? If so, which ?

Figs. 376 and 377 were drawn from plants that had grown a little. When your seeds have also grown a little,

Cotyledon. —

Cotyledon.

FIG. 376.

FIG. 377.

compare them one after another with these pictures. Look at your young bean-plant. Find the first node above the cotyledons. How many leaves are growing there ? how many at the first node of the corn-stem ? how many in each of your growing seeds ?

122 BOTANY.

Observe whether the cotyledons in all cases rise into the light and air. Observe whether all cotyledons are shaped alike, and also whether they resemble the true leaves of the plant.*

EXERCISE LVI. Position of the Embryo in Seeds.

You are now familiar with the different aspects of the embryo in many different seeds. You have seen it large and small, straight and curved, outside the albumen and imbedded within it ; sometimes with flat cotyledons, and sometimes with cotyledons folded or coiled in various ways and degrees. We are now to observe its relation to the parts of the seed.

In studying ovules, you found the hilum and the micro- pyle, and you may find the same parts in the seeds that were once ovules. The hilum of seeds is usually obvious enough, and the micropyle may be easily found. You have only to soak the seed till its coats are distended with water, and, on squeezing, the micropyle is made apparent by the escape of water at that point. The place of the micropyle is important, because the radicle of the embryo always points toward it, and, in sprouting, issues through it, and the relation of the micropyle to the hilum deter- mines the attitude of the embryo. Seeds are straight, half inverted, inverted, and curved, the same as ovules, and

* A word of caution may not here be amiss. There is danger that the sympathy of teachers with bright and interested pupils will lead them to tell in advance what children can find out for themselves by continued observation. The relation between number of cotyledons and venation is an instance of such temptation. By-and-by, when the leaves of his growing plants are well developed, the pupil might be put in the way of discovery, by asking him to make a list of his monoco- tyledons, and to give their venation in each case. Let him do the same with his dicotyledons. He will now see a perfect uniformity of relation in a few cases, and will be curious to know if it is everywhere constant. He will thus arrive at the induction by his own observation.

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I23

the same terms are used to express these facts in regard to them. In a straight or orthotropous seed, the micro- pyle being at the apex, you find an inverted embryo, like Fig. 378. In this case the embryo is said to be antitropal, or reversed.

FIG. 379.

FIG, 378.

FIG. 382.

FIG. 381.

If the micropyle be turned to one side, the embryo will be oblique, as seen in Fig. 380. In this case the em- bryo is said to be heterotropal. Fig. 379 represents the seed which is shown in section in Fig. 380.

If the seed be inverted, or antitropous, the embryo will be erect, as shown in Fig. 381. Here the embryo is said to be orthotropal.

When a seed is curved upon itself so as to bring the orifice next the hilum, or point of attachment (campylo- tropous seed), you may find the embryo presenting the appearance shown in Fig. 382.

When the embryo is in the center of the albumen (Fig. 381), it is said to be axial j and when not in the center, it is said to be .excentric.

There are two modes of folding to which the embryo is subject, which occur uniformly in certain groups of plants. They are cotyledons decumbent — that is, with the radicle folded against their edges ; and cotyledons incum- bent, having the radicle folded against the back of one of them.

CHAPTER SEVENTH.

FLORAL SYMMETRY, PHYLLOTAXY, PREFOLIATION, CYMOSE INFLORESCENCE, ETC.

EXERCISE LVII. Numerical Plan of Flowers.

WHEN, in examining a flower, you count the parts of its calyx and corolla, the stamens and the carpels, and find

that some particular number oc- curs again and again ; and when, in case of deviation, you fre- quently find multiples of this number, the plan of the flower is said to be based upon it. For instance, the plan of the flower represented in Fig. 383 is based on the number three. The plan of the flower represented in Fig. 384 is based on the number four,

and that of Fig. 385 upon the number five. In other words, in Fig. 383, three, or its multiple, six, is the con-

FIG. 383.

FIG. 384-

FIG. 385.

FLORAL SYMMETRY.

125

stant number ; in Fig. 384, four is the prevailing number ; while in Fig. 385 it is five.

What numbers have occurred oftenest in your written descriptions of flowers ? When you describe a flower, observe always what figures you use in numbering its parts, and decide what number the plan of the flower is based upon.

EXERCISE LVIII.

Alternation of Parts in Flowers.

Figs. 387 and 388 represent the stamens and pistil of the flower shown in Fig. 386. Does this picture represent a perfect flower ? Does it repre- sent a complete flower? a regu- lar flower ? a symmetrical flower ? Fig. 389 is a cross-section of this flower, given to illustrate the re- lation of the parts to each other. Observe that the petals alternate with the sepals; that is, they stand opposite to the openings between the sepals. In the same way the stamens alternate with the petals,

FIG. 386.

FIG. 387.

FIG. 388.

and the carpels with the stamens. This regular alterna- tion of parts is spoken of as a symmetrical arrangement

126

BOTANY.

of the flower. Fig. 392 is the cross-section of Fig. 390, and Fig. 391 gives a vertical section of the same flower.

FIG. 389.

FIG. 390.

Are its parts arranged symmetrically ? that is, is the alter- nation perfect ?

You see that flowers present symmetry of arrangement as well as symmetry of numbers, and it is important that you should observe them in this respect. Determine what

FIG. 391.

FIG.

parts of the flower you are studying alternate symmetri- cally, and where the symmetry fails. You will often find these observations valuable in classification.

EXERCISE LIX. Leaf-Arrangement.— Phyllotaxis.

To study leaf-arrangement, get straight leafy stems, or shoots, a foot or more in length, such as are shown in Figs- 393 and 394, from any vigorous tree, shrub, or herb.

PHYLLOTAXY.

127

First separate the specimens having opposite and verti- cillate leaves from those with alternate leaves.

Observe that the successive pairs of leaves in opposite- leaved plants are placed at right angles to each other,

FIG. 393.

each leaf of the upper pair being placed over a space left by the lower pair. They are hence called decussate leaves. In the same way the whorls of leaves in verticillate-leaved stems are so placed that they alternate with each other.

Observe the arrangement of leaves in the stems of grasses, and in stems with equitant leaves.

Put by themselves all the stems in which the leaves are neither decussate nor whorled.

Examine them, one after the other, thus : Take a

128

BOTANY.

small string, and, holding one end of it just below one of the lower leaves of your specimen, carry it up and around the stem (Fig. 395), so that it shall pass just under each successive leaf. Proceed in this way till you reach a leaf standing directly over the one you started with. Your string now includes what is called a leaf-cycle ; that is,

FIG.

394-

the distance in a spiral line around the stem, from one leaf to another placed exactly above it.

Holding the string in place, observe, first, how many times it has wound around the stem ; and, second, how

PHYLLOTAXY.

I29

many leaves it passes on its way. If, in passing from the first leaf to the one directly over it, the string makes but one circuit around the stem, and the third leaf is over the first, so that the cycle includes but two leaves, the fourth leaf being over the second, and so on, you have an ar- rangement like that seen in Fig. 393. The leaves in this example are seen to form two rows along the side of the stem, which are separated by half its diameter.

This is the distichous, two-ranked, or \ arrangement.

If, in passing from one leaf to another directly above it, the string goes but once round the stem, and the fourth leaf is over the first, giving a cycle of three leaves, the arrangement is like that shown in Figs. 394 and 395. There are three perpendicular rows of leaves along the stem, separated from each other by -J its circumference.

This is the tristichous, three- ranked, or -J arrangement.

Again, the string may pass twice around the stem before it reaches the leaf placed just over the first, which, on counting, proves to be the sixth (Fig. 397). There are five longitudi- nal rows along the stem, sepa- rated from each other by f its circumference.

This is the pentastichous, quincuncial, or f arrangement. FlG- 395- FIG. 396.

Observe that the numerator

in the foregoing fractions gives the number of times the string winds around the stem in completing a cycle, while the denominator gives the number of leaves in the cycle.

This fraction is sometimes called the angle of diver-

s

130 BOTANY.

gence of the leaves. In Fig. 393 the angle of divergence is I the circumference of the stem ; in Fig. 394 it is -J-, and in Fig. 396 it is f its circumference.

In studying some of your specimens, the string may pass three times round the stem in its spiral course before you come to a leaf placed over the first, and this leaf may be the ninth in the upward succession, eight leaves being required to complete the cycle. Here you have eight per-

FIG. 397.

pendicular rows of leaves, with an angular divergence of f the circumference of the stem ; it is, therefore, called the f arrangement.

In some plants the leaf-cycle includes five turns of the spiral and thirteen leaves, so that the fourteenth is placed

PHYLLOTAXY. 131

over tiie first. This is the -^ arrangement. There are also the -/f, the £f arrangements, and so on. But these more complex modes are only found where leaves grow in rosettes, as the house-leek, or in the case of crowded radi- cal leaves, or in the scales of cones. In these cases the vertical rows are not distinguishable, and the order has to be made out by processes of reasoning rather than by sim- ple observation.

There is a curious feature of the fractions expressing the angular divergence of leaves. Observe that any one of the fractions of the series is the sum of the two pre- ceding simpler ones. For example, the angles of diver- gence in Figs. 393 and 394 are ^ and -J. Adding these numerators and these denominators, we have -f, the pen- tastichous, or next more complex arrangement. By add- ing in the same way J and f, we get f, while f and f give y5^-, and so on.

The J, -J, and f modes of arrangement are so definite and simple as to be easily discovered ; but it is not worth while, ordinarily, to continue the study of a specimen if it does not belong to one of these modes. A slight twisting of the stem, a considerable lengthening of internodes, or theii absence altogether, renders observation difficult, and the decision uncertain. So, when commencing the study of leaf-arrangement, take care to select the straightest and thriftiest stems for the purpose.

Examine the arrangement of bracts, and see if they follow the same order as leaves.

Observe whether the spirals take the same direction in branches as in the parent stem. When they do, they are called homodromous ; but when they turn in opposite di- rections, they are said to be heterodromous.

Give the numbers of the leaves in each perpendicular series in your specimen showing the \ arrangement (Fig.

393).

In the £ arrangement, what leaf stands over the first ?

I32 BOTANY.

over the second ? the third ? the fourth ? the fifth ? Give the series of numbers that belong to the leaves of each row.

The name applied by botanists to these modes of leaf- arrangement \spkyllotaxU,

EXERCISE LX.

Arrangement of Floral Leaves in the Bud.— ^Estivation, or Prefloration.

In most common flowers, the floral circles, calyx, co- rolla, etc., appear quite distinct ; but have you never ob- served cases in which it was doubtful where the calyx ended and the corolla began ? or, where the corolla ended and the calyx began ? or, even, where the bracts ended and the calyx began ? Have you never seen sepals with the color and delicacy of petals, and in the same flower some sepals that were green, and some more or less like petals? or, the same sepal green without an'd petal-like within? Have you not seen the involucre made up of colored bracts, which looked like a corolla ? Have you not sometimes met with flowers in which you could see the gradual transition from petals to stamens? or in which some of the stamens or carpels were changed to green foliage-leaves ? Have you ever known of single flowers becoming double by cultivation, and of stamens and car- pels replaced by petals ? Did you ever see a leafy shoot growing out from the center of a flower, or of a flower- bud? These appearances are not uncommon, and may be easily observed if you are watchful.

It is from these singular aspects of plants, joined with the study of their development, that botanists have come to regard flowers as altered branches, and floral leaves as changed foliage-leaves. They speak of carpels as carpel- lary leaves, stamens as staminal leaves, petals as corolla- leaves, and the sepals as calyx-leaves.

PREFLORATION. 133

If this be so, the laws of arrangement of floral leaves ought to agree with the phyllotaxy of foliage-leaves. Bot- anists say that they do so agree, and the place where this agreement is best seen is in the flower-bud. The arrange- ment of floral leaves is an important help in determining the affinities of plants.

To observe this arrangement, make a horizontal sec- tion of a bud just before it opens. Be careful to make the section in the upper part of the bud, where the petals

FIG. 398. FIG. 399. FIG. 400.

and sepals are most easily 'seen. Observe with a magni- fying-glass the disposition of parts, and compare your ex- amples with the modes of arrangement here pictured and named.

In VALVULAR prsefloration there is no overlapping of parts. The edges of the sepals and petals just meet, and the flower is almost always regular (Fig. 398).

INDUPLICATE is a form of valvate aestivation, in which the edges are turned slightly inward, or touch by their external face (Fig. 399).

REDUPLICATE is a form of valvate aestivation, in which the edges turn slightly outward, or touch by their internal face (Fig. 400).

In the CONTORTED arrangement, each leaf overlaps its neighbor, and the parts seem twisted together (Fig. 401). It becomes CONVOLUTE when each sepal or petal wholly covers those within it.

In IMBRICATE aestivation, the parts of a floral circle, usually five, are placed as seen in Fig. 402. The first leaf

134

BOTANY.

is external, the fifth internal, and the intermediate ones successively overlap each other.

¥lG. 404.

FIG. 405.

FIG. 406.

The QUINCUNCIAL arrangement is seen in Fig, 403. There are two exterior leaves, two interior, and one inter- mediate.

The VEXILLARY ar- rangement (Fig. 404) is a form of the quin- cuncial, where one of the petals, that ought to be internal, has, by rapid growth, become larger than the others, and external to them, so as to cover them in.

In the COCHLEAR arrangement, inequality of develop- ment has produced the order seen in Fig. 405.

We are reminded of the DECUSSATE arrangement of

FIG. 407.

FIG. 408.

CYMOSE INFLORESCENCE. 135

foliage-leaves by the position of the floral leaves shown in Fig. 406.

The SUPERVOLUTE arrangement is the name given to the folding of the gamosepalous calyx, or the gamopetal- ous corolla (Fig. 407). Observe whether the overlapping is from right to left, or from left to right, as you stand before the flower. Observe, also, whether the mode of arrangement is the same in the calyx and corolla.

The plaiting of a gamopetalous corolla is shown in Fig. 408.

EXERCISE LXI. Cymose, or Definite Inflorescence.

It often requires much skill and patience to determine whether a particular panicle, corymb, raceme, or head, is definite or indefinite.

The buttercup, wild columbine, rose, and cinquefoil, are common examples of cymose inflorescence among alternate-leaved plants, while Saint- John's-wort, chickweed, sedum or live-forever, dog-wood, elder, hydrangea, are opposite-leaved examples. Get as many of these as you can, and begin the study with the inflorescence of an alternate-leaved plant. Compare it with Fig. 409. In this plant each shoot terminates in a flower, and the growth is continued by means of branches. Here the main or primary stem (A, A) terminates with a flower which must, of course, be the oldest of the cluster. The branches (B, B, B) continue the growth, blossom, and cease to lengthen. From these branches proceed others (C, C), and so on.

Such a loose, irregular, definite inflorescence is called a cyme ; but, when the number of branches is greatly in- creased, and the peduncles acquire such lengths as to give a peculiar outline, the cluster receives a more special name. Fig. 410 represents the cymose inflorescence of an opposite-leaved plant. The main or primary stem termi-

136

BOTANY.

B

nates in a flower between two branches. These branches, or secondary stems, also terminate in flowers, each one of

which is situated be- tween branches of the third order, and so on.

In this way is formed a forked or dichotomouscyme. If, in place of two, we have three branch- es, forming a sort of whorl around the primary stem,, and each of these branches has anoth- er whorl of three tertiary branches, and so on, we get a trichotomous cyme. When the branching is carried forward, as seen in Fig. 411, the cyme becomes FIG. 409. globose. When the

central flower is sup- pressed, the process of development is not easily traced.

Suppose that, at each stage of the branching, one of the divisions is regularly suppressed, as shown in Fig. 412, where the dotted lines take the place of the absent branches, the cyme is apparently changed into a one-sided raceme, and the flowers seem to expand in the same way as in the indefinite raceme. In opposite-leaved plants bearing this kind of inflorescence, the leaf or bract op- posite the flower shows that the raceme is definite ; but when, as in Fig. 413, there is no such bract, it is not easy

CYMOSE INFLORESCENCE.

137

to decide whether the cluster is definite or indefinite.

However, the one-sided mode of branching gives the stem

a coiled appearance, which is characteristic of the false or cymose raceme, described £s scorpioid — curved like the tail of a scorpion.

FIG. 410.

FIG. 411.

You may know a cymose umbel by observing that its oldest flowers are in the center of the cluster (Fig. 414), with buds, on short peduncles, sur- rounding them.

A FASCICLE (Fig. 415) is a cymose cluster of nearly sessile flowers.

FIG. 412.

FIG. 413.

A GLOMERULE is a cymose cluster of sessile flowers in the axil of a leaf.

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BOTANY.

What is known as compound inflorescence occurs when the flower-clusters of a plant develop in one way, and the plant itself develops in another way. This state of things is often met with. Compare the development of the sunflower with that of catnip and hoar- hound in this respect.

FIG.

FIG. 415.

The indefinite mode of growth is sometimes spoken of as centripetal, because the flowers open first at the circum- ference ; while definite forms are said to be centrifugal, because here the flowers open at the center first.

CHAPTER EIGHTH.

THE COMPOSITE.

EXERCISE LXII. Parts of Flower-Heads.

To illustrate this chapter, gather all the plants you can find that have the inflorescence in a dense head. The dandelion, thistle, aster, marigold, sun- flower, daisy, dahlia, burdock, mayweed, bachelor's - button, boneset or thorough- wort, golden - rod, lettuce, saffron, cud- weed or everlast- ing, wormwood, tan- sy, yarrow, feverfew, camomile, ragweed, tickseed, elecam- pane, are familiar examples of such plants. For your first observations se-

Florets

Involucre of Bracts

FIG. 416.

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BOTANY.

lect some flower-head in which the parts are well devel- oped, as the marigold, thistle, or dandelion. Fig. 416 shows a thistle-head, with lines pointing to its princi- Florets.

pal divisions.

Fig. 417 represents a marigold, in which the same parts are shown. In Fig. 418 we look down upon the

top of the flower-head, and observe that it pre- sents unlikeness of as- pect, which is still more FIG. 418. plainly shown in section

in Fig. 419.

The parts pointed out in these pictures may be thus denned :

INVOLUCRE. — The outer green circle of a flower-head, often mistaken for a calyx.

THE COMPOSITE.

141

SCALES. — The bracts forming the involucre of a flower- head.

FLORETS. — The flowers of a flower-head.

RAY FLORETS. — The outer petal-like florets of a flower- head.

DISK FLORETS. — The inner florets of a flower-head.

Observe the bract at the base of the floret in Fig. 421. Observe the chaffy, bract-like bodies growing among the florets in Fig. 420. Examine your specimens, and see if, in any case,

FIG. 420.

FIG. 421.

FIG. 422.

you find such things growing out of the receptacle among the florets. These chaffy bodies are known as pale<z. When they are wanting, the receptacle is said to be naked. Separate the naked from the chaffy flower-heads of your collection.

In Fig. 422 you see the convex receptacle at a. Ob- serve the different forms presented by the receptacle in the last four figures. Strip away the florets from your flower-heads, and compare them in this respect. Are any conical in shape ? Are any columnar ? Are any pitted or honey-combed? In Fig. 422 is shown half the involucre of a marigold. Compare the involucres of your collection. They may be hemispherical, conical, inversely conical, squarrose, oblong, cup-shaped, etc. Their scales may be

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BOTANY.

many or few ; narrow or broad ; in one or several rows ; loosely or closely imbricate ; chaffy, spinous, or soft ; re- flexed, colored, etc.

EXERCISE LXIII. The Florets.

Let us now examine, with some care, the structure of florets. The flower-head here dissected is that of the marigold. If you can not get this plant, take the sun- flower, or daisy, or dande- lion, or thistle, or any other flower-heads you happen to have. Of course, it is de- sirable, at the outset of study, to get the largest florets you can find.

Fig. 423 represents a sec- tion of the marigold : a, the ray florets ; b, the disk flo- rets ; c, the involucre ; d, the receptacle ; and e, the peduncle.

Fig. 424 shows one of the ray florets, with its strap-shaped corolla, d the limb, and c the tube. At e is seen the forked stigma of the pis- til ; a is the ovary, and b the limb of the calyx. Compare this picture, or, what is better, a living example, with one of the florets of a dandelion, and carefully note the differ- ences of structure they present.

Fig. 425 represents a disk floret : a, the ovary ; b, the limb of the calyx ; and c, the tubular corolla. Compare this floret with those of the thistle, or any tubular florets in your collection.

In looking for the limb of the calyx in your specimens, you have found very various and peculiar appearances. This part of florets, from its singularity, has received the

THE COMPOSITE

special name of pap- pus. In some, you observe, it does not exist at all, the ad- herent tube of the calyx forming an in- distinguishable part of the ovary ; in such cases the limb is said to be obsolete. Again, it is a mere rim, or border; sometimes it is cup- shaped, or bristly, or composed of teeth, scales, awns, or beards.

C'

FIG. 424.

FIG. 425.

In the dandelion (Fig. 426) and the thistle it is silky. The cause of this singular condition of the calyx-limb may

be that it is starved and stunt- ed while growing, by the con- stant pressure of the florets against

FIG. 426. FIG. 428. FIG. 427.

each other. In the case of the dandelion, while the seed is maturing, the tube of the calyx is prolonged above the ovary into a kind of stalk, and the pappus is said to be stipitate (Fig. 426).

8

144

BOTANY.

But let us return to the florets. We have not yet ex- amined their essential organs. Just below the stigma, in the disk floret (Fig. 425), is a cylindrical body, which, at first, you may not understand. Slit it down, flatten it out, and examine it with your glass. Is not this cylinder com- posed of slender coherent anthers ? Do you not see each anther with its filament, as shown in Fig. 427, and which represents the tube seen in Fig. 428, thus laid open ? The stamens of this floret are syngenesious.

The following is a schedule of the £ and ? florets of the marigold :

SCHEDULE FOURTEENTH.

Organs.	No.	Cohesion.	Adhesion.
Calyx ? Sepals.	5*	Gamosepalous. Limb of narrow scales.	Superior.
» Corolla ? Petals.