TMT JACTFeRooN HT Htate College of Agriculture At Cornell University Sthaca, 2. B. — Library DATE DUE DEMCO 38-297 oe University Library QK 47.K29 Tiiiiinir mann Wi pe eee fe. ( JRE As, CLE at Sa. PPL ( i i A * as THE ELEMENTS OF BOTANY. | THE KLEMENTS OF BOTANY: EMBRACING Orcganocrapuy, Hisrotocy, VEGETABLE PrysroLocy, SystEMAtIC Borany AND Economic Botany. ARRANGED For Scuoou Use or ror InpEPENDENT Stupy. TOGETHER WITH A COMPLETE GLOSSARY OF BOTANICAL TERMS. BY W. A. KELLERMAN, Pz.D., PROFESSOR OF BOTANY AND ZOOLOGY IN THE KANSAS STATE AGRICULTURAL COLLEGE. LATE PROFESSOR OF BOTANY IN THE STATE COLLEGE OF KENTUCKY. FORMERLY PROFESSOR OF NATURAL SCIENCE IN THE WISCONSIN STATE NORMAL SCHOOL, ! COPIOUSLY ILLUSTRATED. PHILADELPHIA: JOHN E. POTTER AND COMPANY, 617 Sansom STREET. NEW YORK: 743 & 745 BROADWAY. W. ( QK +7 K aq ce SG) IN PREPARATION. KELLERMAN’S PLANT ANALYSIS, a Manual of the Wild Flowers of the Northern United States, with Analytical Keys and Complete Glossary. Designed for beginners as well as for those who have had experience in analyzing flowers. This will be a fitting companion to The Elements of Botany. Copyricut sy W. A. Kerierman, 1883, PREFACE. Tue object in preparing this book has been to present to pupils in our schools and to students generally, in a sufficiently condensed form, a comprehensive view of the Vegetable Kingdom. This includes a general survey of the organs of plants, their structure and functions, of the classification of plants according to their supposed genetic relationship, and, finally, of the uses of plants and the application of botanical knowledge in the various pursuits of life. It is not deemed necessary to apologize for pre- senting the minute anatomy or histology of plants as seen in the following pages, much less for devoting a separate part of the work to a discussion of the commonest vege- table products found in commerce, as regards their nature, source, and uses. It is believed this new departure will be welcomed by the great mass of intelligent educators of our country, who think this science broad enough and already sufficiently developed to meet the just demand made upon it not only for something disciplinary and pleasurable, but also for something useful. In case of pupils who will afterward pursue collegiate courses of y) vi PREFACE. instruction, it is believed this book will offer a suitable introduction to extended botanical study; but it has been prepared especially for pupils who end their school educa- tion when, or even before, the ordinary high-school course is completed. It is confidently hoped also that those out- side of schools who are desirous of learning something of Botany will find here an attractive introduction to this important science, for the further study of which the works of Gray, Bessey, and others are so admirably adapted. In Part I. the subject of Structural Botany or Organ- ography is presented in the customary form, yet a slight abridgment of the number of technical terms and the etymologies of the important ones given will, it is believed, be found improvements. The numerous figures in Part IT. will enable the pupils, even without the aid of microscopical appliances, to get a clear idea of the minute structure or histology of plants, upon which, to a large extent, physiology is based. In Part III. the arrangement of the various groups of plants corresponds quite closely to that in recent publica- tions by eminent botanists. Departures made by Bessey in his Botany seem desirable, and, therefore, have been followed. Only a limited number of representative groups have been mentioned; and should the teacher find this number too great for mastery on the part of his pupils, a further abridgment can readily be made. In Part IV. only a few, yet in general the most PREFACE. vii important, vegetable products have been mentioned and briefly described. The order of sequence of the groups is that used by Weisner in his Rohstoffe des Pflanzenreiches, a book which is the source of much of the information, especially of that relating to anatomy, contained in this part. The Appendix contains suggestions that will, it is hoped, be of advantage, especially to those who study without the assistance of a teacher. All minute measurements have been given in fractions of an inch, although the great advantage of the use of the metric system is not in the least questioned. But pupils are not, as a rule, familiar with the latter, and can only slowly and gradually be taught to substitute it for what they have learned in early youth and practiced since. The same in substance may be said with reference to the Centigrade and Fahrenheit’s thermometers, the familiar scale of the latter being used in this work. Especial attention is called to the tables given in the Appendix of the equivalents of an inch in millimetres, also the equiva- lents of the degrees of Fahrenheit’s scale in degrees on the Centigrade scale. Nearly three hundred of the illustrations are original. Figs. 223a and 324a were taken, by permission of the publishers, from Wood’s Class-book of Botany; Figs. 134, 135, and 308 from Gray’s Botany; Figs. 342, 343, 344, 345, 846, and 347 from Le Conte’s Geology; Figs. 148, viii PREFACE. 169, 182, 185, 188, 120, 221, 234, 237, 238, 241, 247, 248, 251, 253, 254, 257, 264, 266, 277a, 282, 300, and 301 from foreign authors, as Sachs, De Bary, and others. Twenty- two illustrations of ornamental plants were furnished by C. W. Seelye, editor of Vick’s Magazine, from publications of James Vick. I would say finally that I have been assisted by my wife in the entire preparation of the book, and to her equally with myself is to be attributed any merit that it may contain. State AGRICULTURAL COLLEGE, Manuartran, Kansas, 1883, W. A. K. CONTENTS. PAGE INTRODUCTION... +... BS a Tee ee ee eee: EL. Part I—ORGANOGRAPHY. PARTS Of ACPUANT S34 sae ee @ tel Bac Be RS 15 WH ROOD eee se! a see ea ee Rae he) SOS LS «« AG Tur Stem. .... SRL we ew ‘ ee « 21 TEE SBUDs. oa bra) 4), a we Soe ew AAS ohh a “25 TEE: GAR yon Bee a OR SR ew a cas ee ew 25 Pie GOWER Y sues a eae a eee ee ep ar ee S89 POLLINATION AND FERTILIZATION. » 2 + eee oe eee 6 O4 THE FRUIT: 4 34 & @ & ¥ % aces Orin rag tcne mene 6 Seaicee CF Part II—HISTOLOGY AND PHYSIOLOGY. PE) CRIA.) wise a ee ek OK shies eas egg 3h tt” FOS dinate 72 THE CELL-CONTENTS . 64.0 ee eee eee of 16 ee Geo CBZ AL ISSU Bee as ees. as SER ee a A RS 87 WADERS ecards er doe? hs Si ce Sie ee aera . oo ee eae 100 FOOD-ELEMENTS,: 3 3 24 a @ es we be ae oes. e. 104 ASSIMILATION AND METASTASIS... 2. eee wane 106 RESPIRATION « 6.506002 30 ce a ea arcs Tuan Gan sart eos » » 109 TEMPERATURE... + ee wee 6. Wee gee Je ey a a ae 109 DSIGUHT sh fae Sg BR ee eh ae eS) ew SS 111 MovEMENTS .....008-6 Suk eeieie as Gee ae rides ia aoa 112 Part III.—SYSTEMATIC BOTANY. CLASSIFICATION. » . 2 + se ee ee) SS eee act ae Be TF “ DIVISIONS . 1. 4s oe ea er ee ee eS 6. oe te ve Yo AD: PROTOPHYTA $ % « % 8 es HHS ww we aa ay a Se ee ZX GOSPOR ED 026.0 bce, SiR) Ge BS a sa te wat 126 OGSPOREH...... i le ONES Se ES SR SS 132 x CONTENTS. PAGE CARPOSPOREE . 1... +e eee eee oe ee ee ee 186 BRYOPHYTA. . 40804 8 wes eee et Se ae Shee Te le ee eer AS: PYERIDOPHYTA 4 @ @ @ Ww ee we eS ei eile 8 eS « « 153 PH@NOGAMIA.. . we eee te alisy Ao GIA Dar ciate 4a acd cot Gerd GY MINOSPERM iis, S.-62 4) We a se es aA ai Passage! wad Ses ogy ae G2: ANGIOSPERMM os 8 4 6 3 GS ae ww RRR ee we 166 MONOCOTYLEDONES «2.1 1 se eee tee ee et ws 169 DICOTYLEDONES. sa we Rw ee Sas we RS Badges at, 184. GEOGRAPHICAL DISTRIBUTION... « - oe Be a eee a QBE Fosst PLANTS... +... extn ves caayan caataee ger contiae Ys » 2384 Part IV.—ECONOMIC BOTANY. THE GUMS % & « 8 ss) 4 we ww éce ew wR oe. « 244 Tur RESINS.......-. bay alte So aia fd A IS, 247 Tur CaoutcHouc GROUP. ......eee. OMe a eve ee EE Opium AND CATECHU GROUP... 1 ee ee ee enews 265 VEGETABLE FATS AND WAX 2.1. 8. see ee se wae 268 CAMPHIOR: ix) See Bl ms HE. OH ae ee A 272 STARCH AND SUGAR ..... ee eae bas ieee a 27S FYBRES sg. a a a eay SL Seder Gee ed ED ee. EE 5 as ve QT! Tuer Cortex or BARK ...... ee ee Sid ate ee 29M, WOODS: ines Acdsee ds) Se aia ae) Vegas Sha ce <« « 296 Roots AND RHIZOMES. . . 2. 5 se ee ee eee » « . 803 TERA VRS! ed apes. wet ae es) So ay ee we oe Ce wh HP 305. EPBOW ERS: cio oe cae ze’ Salsa SSS ces neh pos Ge we Fe ee 3S Se B08 DEEDS AND) EP RUIS oe Gees eS ey A RE aS RS ees ea 811 GALLS AND CRYPTOGAMS . «+ 1 ees eee ee rene 320 APPENDIX. SuGGESTIONS FOR STUDYING. . «2 eee wee we ee ee 823 SUGGESTIONS FOR COLLECTING. .... s+ se ead ee « B23 Tere MICROSCOPE ee Se) seb tog) ta) de ek Bie de weed we 325 Microscopic PREPARATIONS. . + + se ee ee ee ewe 327 Tar HERBARIUM. § 6 6 6 2 3 6 4 ww a denon te CR, 332 GLOSSARY . . - eee ee abi Me RB Se Ue car ew: te erteen, gi BBS TABLES OF EQUIVALENTS. « «6 e+ ee © © © © « + 3809, 360 ELEMENTS OF BOTANY. ‘INTRODUCTION. Broxoey is a term now used to denote the study of all living things or organisms, namely, Plants and Animals. These, as contrasted with minerals or inorganic matter, are, in general, distinguished by the possession of organs, or special parts of their structure, designed to perform cer- tain functions. The very lowest or simplest forms of living matter, however, are often so homogeneous and structure- less, or “ organless,” that they are with difficulty separated from some of the complex, inorganic substances; in other words, there is the most intimate connection between the mineral, or inorganic, and the organic kingdoms. Between the commoner and widely-divergent representatives of these, as, for example, between a crystal of quartz and a tree or a toad, there are numerous patent, distinguishing characteristics, besides the absence or presence of organs ; prominent among which is the fact of parentage, or power on the part of organisms to reproduce themselves, and so, by offspring, perpetuate their kind. That department of Biology, which treats of plants, is called Botany. It is almost inseparable from ZooLoey, which treats of Animals; for the lowest organisms can . @1) : 12 ELEMENTS OF BOTANY. often be called plants with as much propriety as animals, and animals with as much propriety as plants, on account of the simplicity of their structure and the few characters they present, upon which a systematic classification may be based. It has been proposed to form another Group, called the Prorista, to receive these low organisms; the higher representatives of the Vegetable and Animal King- doms are readily distinguished by many anatomical and physiological characters. Plants feed on mineral or inorganic substances. Animals derive their food from plants. Many of them, as the her- bivorous animals, feed exclusively on vegetation. Carniv- orous animals, devouring the vegetable-feeders, depend no less really though indirectly on plants for food. Plants in general consume carbonic dioxide, and liberate oxygen. This is not true, however, of the parasitic plants, called Fungi. Animals consume in respiration oxygen, and liberate carbonic dioxide. The two kingdoms are thus mutually dependent. The surface expansion for absorption, etc., is very exten- sive in case of both plants and animals. In case of plants, however, it is mainly external, as the surface of the roots, rootlets, rhizoids, stems, and leaves; in case of animals it is, in the main, internal, as the alimentary canal, the vas- cular and respiratory vessels, ete. Plants possess chlorophyll, that is, green coloring matter, by reason of which they are able to convert the inorganic food into organic matter. Fungi and other parasites and saprophytes are destitute of chlorophyll, and these plants appropriate to their own use the food assimilated by chloro- phyll-bearing plants. Animals, with the exception of a very few low forms, do not possess chlorophyll. INTRODUCTION. 13 Very many vegetable substances or products are ternary compounds, or composed mainly of oxygen, carbon, and hydrogen; while very many of the animal substances or products are quaternary compounds, or composed of oxygen, carbon, hydrogen, and nitrogen. Most plants, but by no means all of them (especially the lower forms), are stationary, or have no power of locomotion; while animals, also with numerous exceptions, locomote freely from place to place. Sensation is possessed by plants in a very much less marked degree than by animals. The study of plants may be solely with reference to their visible parts or organs, and this part of the science is called ORGANOGRAPEY, or Structural Botany. When the investi- gation touches the minute or microscopic structure of plants or their parts and products, it is called Minute Anatomy, or Histotocy. The study of the parts of the plant with reference to their functions or office, or their so-called vital actions, comes under the head of VEGE- TABLE PuysioLocy. The classification of plants and what directly appertains to it constitutes Sysr—matic Borany. All the plants of any region are called the Flora of that region. Fossrr Borany treats of fossil plants, or those which existed in previous geologic times, and whose remains or impressions are found in rock-strata, The application of botanical knowledge in the arts, industries or pursuits of life is designated by the term AppLiep Botany. This may be Agricultural, Horticultural, or Medical Botany, etc. Economic Borany is commonly used to indicate a study in general of the vegetable products and their uses. PART 1. ORGANOGRAPHY. x. If we examine any common plant, such as a Grass, Rose-bush, Willow, or an Oak, three distinct parts will be found, namely: I. Roor. II. Srem. HI. Leaves. 2. The Root, or descending axis of the plant, generally grows downwards into the ground, sends out numerous branches, and thus firmly fixes the plant in its position. It also absorbs from the soil water or moisture, which con- tains plant food held in solution. ‘Leaves, or scales repre- senting leaves, are never found on the roots. 3. The Stem, or ascending axis, generally grows upwards, and furnishes the support for all the parts which grow above ground. It may be herbaceous,—that is, of soft tissue, like the Pansy,—or it may be woody, like the Lilac, or Willow-tree. 4. The Leaves are inserted on the stem or its branches. They are generally of a deep-green color and flattened shape. Their office is to convert the inorganic food, which has been absorbed by the roots and conveyed to them by the stem, into organic matter. From them more or less watery vapor is continually escaping. 5. Hairs, or Trichomes, may occur on any part of the plant, as on roots, stems, or leaves. They are mostly (15) 16 ORGANOGRAPHY. hair-like in shape, often very small, but they are some- times long, and may form a dense covering, and hence afford protection for the plant. They may also take the shape of scales, glands, bristles, prickles, etc. THE ROOT: 6. The Root is present in nearly all of the higher plants, as trees, shrubs, and herbs, but wanting in Mosses, Liverworts, Fungi, and Alge. It is usually des- titute of color, but may be brownish, yellowish, reddish, though never green. In case of some plants (Mosses, Liverworts, etc.), there are root-hairs, called rhizoids (Gr. rhiza, root), which have the same function, but not the same structure, as the true roots. 7. The root is generally found underground, where it sends out numerous branches, without any particular order; and these, in turn, branch again and again into smaller roots, called Rootlets. The plant is thus firmly fixed in its place. These rootlets, or their minute branches, are covered with numer- ous hairs, sometimes called jibrille (Fig. 1). In Fig. 2 the terminal portion of a rootlet, with root-hairs much magnified, is shown. In Fig. 1. Wheat in different stages (I, II, III, IV) of germination: 7, root with root-hairs ; s, particles of adhering soil; s#, stem, THE ROOT. 17 many cases, as in the seedling of Wheat, Flax, etc, these may be seen by the unaided eye, appear- ing as a woolly cover- ing. The special office of these is to absorb the dissolved food from the soil. 8. When aseed germi- nates, it generally sends a single root (radicle, Fig. 3,r.d.) downwards, which is called the primary root. This may continue to grow, and remain larger than any of its branches or side-roots which it sends out, and in this case it is called the main, or tap-root. g. The tap-root, when not woody (as in shrubs and trees), may be- come fleshy, that is, thickened, as, for example, in the Carrot, Turnip, etc. This is in consequence of a deposit of nourishment which has been elaborated or prepared in the green parts of the plant. When it is larger at the top, or where it joins the stem, and tapers gradually down- wards, it is said to be conical (Fig. 4); if it is turnip-shaped, that is, very large above, tapering abruptly, and becoming very slender below, Fig. 2. Portion of a root, with root-hairs, highly magnified. Fig. 3. The Bean in different stages of germination: cot, cotyledons; Z/, plumule; 7.d., radicle ; cau, caulicle ; dys, leaves. 2 18 ORGANOGRAPHY. it is napiform (Lat. napis, turnip; Fig. 5); when spindle- seEe> or thick in the middle, and tapering to both ends, it is said to be fusiform (Lat. Jusis, spindle; Fig. 6). io. There may grow from the plantlet, when a seed sprouts, several roots, instead of a single one, as in the Indian Corn, Wheat, Pea, ete. (Fig. 1, etc.) In such case they are called multiple primary roots. Sometimes they become enlarged, as in the Sweet-potato, Dahlia, etc., and thus serve as reservoirs of plant food. They are then said to be tuberous (Fig. 7). In grasses and many other plants they are numerous and thread-like, and are called fibrous roots (Fig. 8). 11. Secondary roots may arise from the different parts of the plaut,—stem and branches,—whether above or below ground. They are called adventitious roots. They are common in creep- ing plants especially at the joints, and their production is favored by contact with moist soil. In the Trumpet Creeper, Poison Ivy, ete., they assist the plant in climb- ing, and, since they do not grow into the ground, they are called aerial roots. 12. Aerial roots are more common in moist tropical Fig. 4. A conical root. Fig. 5. A napiform root. Fig. 6, A fusiform root, ; Fig. 7. Tuberous roots. Fig. 8, Fibrous roots. = THE ROOT. 19 countries, especially in deep forests where the light is parti- ally excluded,—it being unfavorable to their development, A notable example is furnished by the Banyan-tree of India, and some other Fig-trees, whose outstretched branches send down adventitious roots, that grow into the soil, and thus become supporting columns. The Screw-pine is sometimes wholly propped up by roots that originate some distance from the ground. The Sugar- Cane produces aerial roots similar to those of Indian Corn, but they develop from joints higher up. The seeds of the Mangrove of the West Indies sprout before falling from the tree, and send a long root, or radicle, down into the mud, in which these trees grow, thus gaining a foot- hold before severing their connection with the parent tree. 13. Aerial roots, whose function is somewhat different from the above, are found in epiphytes (Gr. epi, upon; phyton, plant), or air-plants. They generally grow on other plants, as their name signifies, but their roots serve merely to give the plant attachment, and the food is derived wholly from the air. Many of the beautiful Orchids of the Tropics are of this nature. The Epiden- dron, or Tree Orchis (growing on a species of Magnolia), and the Tillandsia, or Spanish Moss (hanging in tufts or festoons from trees), of the Southern States, are epiphytes. Many Mosses, Lichens, ete., are epiphytic, though destitute of true roots. 14. Certain plants not only fix themselves to, but also draw their nourishment from, other plants. Such are parasites. They send their roots, or what answer func- tionally to them, into the tissue of their host and absorb the nourishment which the latter had prepared for its own use, True parasites are destitute of the green substance in 20 ORGANOGRAPHY. leaves, called chlorophyll (Gr. chloros, green ; phyllon, leaf’), -in whose presence (in sunlight) the plant can convert the inorganic matter into plant food—that is, organic matter. 15. The Fungi (as Moulds, Blights, etc.) are parasitic either on living or decaying substances. The Beech-drops and Indian-pipe are attached to roots and draw their nourishment therefrom. The leafless Cuscuta, or Dodder, is a slender, yellowish parasite of peculiar nature. The seeds sprout in the ground, but the plantlet, as soon as it appears above the surface, seeks for plants around which to twine; if unsuccessful it soon dies; but if it finds a proper plant, it sends its rootlets, in the form of suckers, into its host, by means of which it absorbs sufficient nourishment for its growth and development; the stem of the parasite then dies, and thus severs its connection with the soil. 16. The Mistletoe of Europe, and the false Mistletoe of this country, have chlorophyll in their leaves, and are, therefore, capable of assimilation, that is, of converting inorganic into organic matter; or, in other words, of pre- paring their own food. Yet they do this only in part. They draw a portion of their food from the trees on which they grow, and are to that extent, therefore, parasitic. The nature of the yellowish or whitish leafless plants, which are fixed to the ground, should not be misunderstood. They do not draw their nourishment from the soil, but from underground roots. Neither should all subterranean parts of plants be regarded as roots, since stems sometimes grow underground. Their true nature, however, is easily deter- mined by the buds and scales (modified leaves) which they produce. Such, for example, are the Irish-potatoes, root- stock of Flag, etc, THE STEM. 21 THE STEM. 17. The most striking differences in stems of various plants is in regard to their size and texture. A stem whose tissue is soft (mostly green) and not woody is said to be herbaceous. An herb which completes its growth and dies the same season is called an annual; a biennial herb, such as the Turnip, Carrot, ete., requires two years to complete its growth and produce seed ; an herb is perennial when the root continues to live for several years, although the stem every year dies down to the ground, a very small portion only remaining, from the buds of which the shoots arise the following year. If the stem is woody, though not growing to a great height, it is said to be fruticose (Lat. frutez, shrub), or shrubby; when approaching a tree in size it is arbor- escent (Lat. arbor, tree), and when forming a proper tree-trunk it is ar- boreous. WOE GGs OS Wag 18. The stem of every plant is ver- ee eae ae tical in its early stages of development; this direction is often maintained, when the stem is said to be erect. If it is prostrate or trailing it is said to be procumbent. A decumbent stem is one that reclines on the ground after having arisen at the base somewhat above it. A stem, climbing by tendrils or rootlets, is said to be scandent; when twining around other objects it is voluble. Stems which grow underground are called subterranean stems. 19. The majority of stems and branches are more or less round (Fig. 9), but many of our common plants, for exam- ple, the whole family Labiate (“lip-shaped flowers”), have Fig. 9. A round stem. Fig. 10, A square stem. Fig. 11. A flattened stem. Fig. 12. A winged stem, 22 ORGANOGRAPHY. square stems (Fig 10). Some plants, as the Wire-Grass (Poa compressa, L.), have flattened stems (Fig. 11); others may be winged (Fig. 12). Those of fi): Grasses and Sedges are conspicuously //, jointed and sometimes hollow, and have ' received the special name of culm (Fig. 18). The trunk of the Palms, and the like, is called caudex. 20. Certain forms of branches are used by gardeners for the purpose of propa- gating by buds. Such are Suckers, Stolons, Offsets, and Runners. Suckers arise from underground stems. Stolons are trailing or reclining branches which take root where they touch the soil. Offsets are short Stolons, like those of the House-leek. Runners are slender, leafless creeping branches, which, when the full length is attained, take root at the tip, form a bud, and develop an independent plant. 21. Some tendrils are slender branches destitute of leaves and intended for assist- anceinclimbing. Examplesare furnished by the Grape-Vine, Virginia Creeper, Squash, etc. (Fig. 14). They generally grow out straight until some slender object is reached, around which the tips Fig. 18. Culm or stem of Grass, Fig. 14. Tendril (2) of the Wild Balsam-apple (Echinocystis), attached at the tip and coiled to the right (7) and to the left (2), THE STEM. 93 hook. Then the whole tendril shortens by coiling up spirally, thus bringing the plant nearer the support. The Virginia Creeper . develops the ten- dril-tips into adher- ing disks when it climbs walls or smooth trees (Fig. 15). Other ten- drils, as of the Pea, etce., are modified leaves instead of branches. Spines, or thorns, are sometimes stunted and hardened branches, as in neglected Pear-trees, Plum-trees, etc. (Fig. 16). 22. Subterranean stems and branches may seem on cursory examination to be little, if at all, different from roots. But they are jointed, and roots are not; they have modified leaves in the form of scales—always absent in roots; buds may generally be found on them, but roots never produce buds. Four com- mon types of sub- terranean stems are the Rhizome, Tuber, Corm, and Bulb. The rhi- zome (Gr. rhiza, Fig. 15. Tendril, which ends in coils (¢) and disks (¢) of the Ampelopsis, or Virginia Creeper. Fig. 16. Spine or stunted branch of the Crab-apple. Fig. 17. Rhizome (72) of Mint: 7, roots ; sz, stem, 24 ORGANOGRAPHY. root) is very common, as in the Mint, Couch-grass, ete. ; it is merely a root-stock, or stem’ growing under the surface of the ground, pro- ducing roots, also leaf-scales and buds (Fig. 17). A tuber is a thickened por- tion of a root-stock. The Potato is the commonest example, the “eyes” being buds (Fig. 18). The corm igs a very short, thickened root-stock, with roots below and buds above. 23. The bulb is an extremely short root-stock, pro- ducing, like the corm, roots from the under side. It is covered with leaves, or the base of leaves, in the form of thickened scales. If the latter are broad, and cover all that is within, the bulb is said to be coated (Fig. 19), or tunicated (Lat. tunica, covering). But if the scales are narrow and separate, as in the Lily, the bulb is said to be scaly (Fig. 20). The small buds above ground, as in the axils of some Lilies, ete., are called bulblets. The bulb, like the corm and tuber, is a reservoir of Fig. 18. Potato tuber (¢); 7, roots; sf, stems, Fig. 19. A coated bulb, Fig. 20. A scaly bulb, THE LEAF. 95 nourishment. The former contains the nourishment in the leaves (base of leaves), and the two latter have it in the thickened stem itself. 24. The Bud.—At definite places on the stem occur buds, which are simply undeveloped branches or shoots, The scales of the buds are small leaves, and that on which they are situated is the stem (as yet undeveloped). The bud at the end of the stem is called the terminal bud (Fig. 21, ter); the others are the lateral buds. Of these, the majority occur in the axils of the leaves (or if the leaves have fallen, they may be seen just above the leaf-scar), and for this reason they are called axillary buds (Fig. ff 21, ax). Sometimes one or two are , {A produced on either side of or above the axillary bud, and in such case they are called accessory buds (Fig. 21, ac). Occasionally their place of origin is indefinite or irregular; they are then called adventitious buds (Fig. 21, ad). Many of the lateral buds fail to develop into branches the following year, often remaining dormant for several years; such are latent buds. THE LEAF. 25. The Leaf is that organ of the plant which is intended primarily for the presentation of a large amount of surface expansion. Accordingly, we find it, as a rule, very broad and long compared with its thickness. Ordi- nary leaves, or foliage (Lat. folium, leaf), exhibit this Fig. 21. Buds: ¢ev, terminal; ax, axillary ; ac, accessory; ad, adventitious. 26 ORGANOGRAPHY. typical form; besides these there are many modified forms, some of which have departed so far from the type that their true nature can be understood only when we see all the intermediate forms or gradations connecting the twoextremes. Such are Cotyledons, Scales, Spines, Tendrils, Pitchers, _ and Fly-traps. 26. The two halves into which a Pea, Bean, etc., readily divide are _ called the cotyledons (Gr. kotula, cup), or seed-leaves (Fig 22, cot). If they be observed, in case of the Pumpkin and certain other plants, some time after germination they will be found to have changed their > shape somewhat and become green, like ordinary leaves. As a rule, however, the cotyledons are simply to nourish the plantlet during germination. In the bulb- scales is stored up food for the early growth of the plant the following season. such bulbous plants as the Hyacinth, etc., by the production of flowers in advance of the leaves. 27. The leaves of underground stems are generally reduced to mere scales. These bud-scales, which protect the tender ~ : parts within, are modified leaves. A gradual transition between them and the This nourishment is consumed, in Fig. 22. Different stages in the germination of the Bean: cof, cotyledons; r, radicle ; 7, plumule. Fig. 23. Spines, which are modified leaves, of the Barberry. THE LEAF. 27 first foliage leaves may often be traced, as in the Lilac, Hickory, ete. When spines occupy the place of leaves, they are modified forms of the q latter. In the Barberry all gra- dations may be seen on a single shoot (Fig. 23). The leaf, or a portion of it, may become changed into a tendril for climbing, as in the Pea, Vetch, etc. (Fig. 24). 28. Very interesting modifications of leaves are furnished by the Pitcher-plant (Sarra- cenia), Sundew (Dro- sera), and the Venus’s Fly-trap (Dionea). The leaves of Sarracenia are hollow cups or tubes (Fig. 25), covered within with hairs directed downwards. They are generally half-full of a liquid, into which insects may fall, and become macerated, and their juices are then absorbed by the plant. The Drosera is also car- nivorous, feeding on small %.4 insects which alight on and are held fast by viscid ten- tacles or hairs on the upper side of the leaf. The leaves of Dionea (Fig. 25a) have at the top two or three lobes furnished with a marginal Fig. 24, Tendril of the Pea-leaf. Fig. 25. Leaf, having the form of a pitcher, of Sarracenia, or the Side-saddle Flower. Fig. 25a, Leaves of Venus’s Fly-trap. 28 ORGANOGRAPHY. row of stout bristles, and three or four slender ones on the upper surface. When the bristles on the upper surface are touched by a small insect, the lobes suddenly close in on it and the prisoner is then digested and consumed. 2g. The leaves are said to be alternate (Fig. 26) when there is but a single leaf at each node or joint of the stem. Examples of this arrangement are very numerous, as the Apple, Oak, Elm, Willow, Dock, etc. If two leaves occur at each node, they are said to be opposite (Fig. 27), as the Maple, Ash, Peppermint, Catnip, etc. Some- times there are three or more leaves at each joint, as in Cleavers (Galium), Trumpet-weed (Lupa- torium purpureum, L.),etc. In this case the leaves are said to be verticillate (Fig. 28). In the Pines and Larch the needle-shaped leaves are in clusters, that is, they are fascic- ulate (Fig. 29). If leaves grow from the base of the stem, but appearing to come out of the ground, they are radical (Lat. radix, root). Those leaves inserted on the stem are cauline (Lat. caulis, stem). 30. If on a straight, leafy shoot of an Elm, Cherry, Apple, Oak, Willow, etc., a thread be passed from the Fig. 26. Alternate leaves. Fig. 27, Opposite leaves, Fig. 28. Verticillate leaves, Fig. 29, Fasciculate leaves, THE LEAF, 99 lowest leaf to the one next above, and continued around the stem in the same direction to the successive leaves above, the thread will be found to take a spiral course; thus the leaves are seen to be spiral in their arrangement on the stem. In the Elm the third leaf stands directly over the first, and to reach it the thread has passed once around the stem, or, as it is usually said, the cycle is complete when the third leaf is reached, and it is expressed by the frac- tion 3. The numerator denotes the number of turns; the denominator, the number of leaves encountered. Experi- menting in a similar manner with the Alder, the fraction 4 is obtained, and with the Cherry, 2. In the latter case the stem would be encircled twice before a leaf is found (the sixth), which is inserted directly over the first, and five leaves are contained in the cycle. In a similar manner the fractions $ with the Flax, ,, with the Flea-bane, .§- with the House-leek, 44 with cones of some Pines, and 24 with some Firs, would be obtained. 31. If now vertical planes be passed through the points of insertion of the several leaves and the axis of the shoot, the angle formed by any two planes, in case of the Elm, whose cycle is 3, will be one-half of 360°, or 180°—that is to say, the angular divergence of the leaves is 180°. In like manner, the angle formed by the planes through the points of insertion of the leaves and the axis of the shoot of the Alder, whose cycle is 4, will be found to be one-third of 360°, or 120°—or the angular divergence of the leaves in this case is 120°. And with the 2 cycle, the angular divergence of the leaves is two-fifths of 360°; with the $ cycle it is three-eights of 860°, and so on for every cycle. 32. If the fractions 4, 4, 2, $, +5, oh, 4, etc. be exam- ined, certain definite relations will be seen to exist. For 380 ORGANOGRAPHY. instance, the numerator and denominator of any fraction may be obtained by adding respectively the numerators and denominators of the two preceding fractions. The numerator of any fraction is the same as the denominator of the second preceding fraction. Spirals may be con- structed which will show the arrangements indicated by the several fractions, and exhibit at the same time the angular divergence of the leaves (Figs. 830-33). Such a view may actu- ally be obtained by looking from above at the shoot in the direction of its axis, 33. If a num- ber of leaf-buds be dissected it will be found that a difference prevails in regard to the Z/ vernation (Lat. Badin * ae a z ver, Spring), or the 32 33 disposition of the scales or leaves in the bud. The arrangement of these leaves in reference to each other is, in general, like their arrangement on the stem, but more will be said of this hereafter, when treating of flower-buds. Each separate leaf is generally bent or folded or rolled up. When the upper part is bent down upon the lower (e.g. Tulip-tree)” it is said to be inflexed, or recline. When the two halves are folded together, face to face, it is conduplicate Figs. 80-88. Spirals showing angular divergence of leaves, 3, 4, 3, 9. THE LEAF. 31 (Fig. 34). If the leaf is folded like a fan (e.g. Maple) it is said to be plicate, or plaited. It is circinate (eg. Ferns) when rolled from the tip downwards (Fig. 35); con- volute (eg. Plum) when rolled from one edge into a coil (Fig. 36); when rolled from both edges inwards (e.g. Violet) it is involute (Fig. 87); when rolled outwards (e.g. Azalea) it is revolute (Fig. 38). 34. A leaf may have three parts, namely: the blade, or lamina, which is the expanded portion (Fig. 39, 67); the petiole (Fig. 39, pet), which is the stem of the leaf; and stipules, which are the appendages at the base of the petiole (Fig. 39, stip). The stipules are very often want- ‘ing, in which case the leaf is said to be exstipulate. If the blade is inserted directly on the stem (which is the case when the petiole is absent), the leaf is said to be sessile. The blade consists of a net-work of veins or skeleton of woody tissue, and the soft, green tissue between the veins called parenchyma (Gr. para, by; enchein, to fill in). When one vein surpasses the others in size it is called the midrib (Fig. 39, mr.) ; its branches are the veins (Fig. 89, vn), and the branches from the veins are the veinlets (Fig. 39, wn). 35. If the venation of a large number Figs. 84-38, Vernation: 34, Conduplicate; 35, Circinate; 36. Convolute; 37. YInvolute; 38. Revolute. Fig. 39. A leaf: 42, blade; Jet, petiole; s¢i, stipules ; m.r., midrib; va, veins ; vn, veinlets; af, apex, 32 ORGANOGRAPHY. of different kinds of leaves be examined, it will be found that two types prevail. The one is represented by such leaves as the Lily, Flag, Grass, Corn, Wheat, etc., in which a number of conspicuous veins ex- tend from the base to the apex of each leaf, approximately par- allel to each other, and this fact has suggested the name par- 0 allel-veined (Fig. 40). The other type is seen in the Oak, Elm, Maple, Catnip, Mallow, Dock, etc. The veins here form a net- work, and are said to be netted-veined, or reticu- lated. Of the latter there are two sorts: the veins may branch from a midrib (Fig. 41), when they are pinnately-veined (Lat. pinna, feather); or they may branch from 3, 5, 7, ete., ribs (Fig. 42), in which case they are palmately-veined (Lat. palma, palm). 36. The principal shapes assumed by leaves are: linear, narrow, long, and of the same breadth throughout (Fig. 43); lanceolate (Lat. dancea, lance), 45 46 47 48 Fig. 40. Parallel-veined leaf, Fig.41. Pinnately-veined leaf. Fig. 42. Palmately- veined leaf. Figs. 43-48, Shapes of leaves: 43. Linear; 44, Lanceolate; 45. Ob- long ; 46. Elliptical; 47. Oval; 48, Oyate, 41 43 44 THE LEAF. 33 long and narrow, tapering upwards and downwards (Fig. 44); oblong, twice, or thrice, as long as broad (Fig. 45) ; 50 51 62 53 elliptical, oblong, with a flowing outline (Fig. 46); oval, broadly elliptical (Fig. 47); ovate, shaped like an egg, the broader end downwards (Fig. 48); orbicular, circular in outline, or nearly so (Fig. 49); oblanceolate, like lan- ceolate, except with the more-tapering end downwards (Fig. 50) ; spatulate, shaped like a spatula, that is, round above and narrow below (Fig. 51); obovate, ovate, with the narrow end downwards (Fig. 52); cuneate (Lat. cunea, wedge), shaped like a wedge (Fig. 53). 37. As to the base, leaves may be: cordate (Lat. cor, heart), heart-shaped (Fig. 54); reniform (Lat. renes, kidneys), kidney- shaped (Fig. 55); auric- ulate (Lat. auricula, little ear), with ears or blunt i‘ projections (Fig. 56); 54 55 sagittate (Lat. sagitta, arrow), with pointed projections downwards (Fig. 57); has- tate (Lat. hasta, spear), with pointed projections outwards Figs. 49-53. Shapes of leaves: 49. Orbicular; 50. Oblanceolate; 51. Spatulate; 62. Obovate ; 63. Cuneate. Figs. 54,55. Base of leaves: 54, Cordate; 55. Reniform, 3 34 ORGANOGRAPHY. (Fig. 58); peltate (Lat. pelia, shield), when the petiole is attached to the under-surface near the middle (Fig. 49). 38. The apex of leaves may be: acuminate, ending in a prolonged point (Fig.59); acute, ending in an acute angle (Fig. 60); obtuse, with a blunt point (Fig. 61); 56 57 58 truncate, with the end asif cut square off (Fig. 62); emarginate, notched at the end (Fig. 63); obcordate, with a deep notch, or inversely heart-shaped (Fig. 64); cuspidate (Lat. cuspis, point), tipped with a sharp, stiff point (Fig. 65); aristate (Lat. arista, awn), with a long bristle or awn (Fig. 66). 39. The margin of leaves may be: entire, that is, the edge is an even line without any notches or teeth (Fig. 58); serrate (Lat. serra, saw), with teeth like a saw pro- jecting towards the apex (Fig. 67); dentate (Lat. dens, tooth), with teeth pointing outwards instead of forwards AMSA (Fig. 68); crenate (Lat. crena, scallop), scalloped (Fig. 69); undulate (Lat. undula, wave), wavy (Fig. 70); incised, when the edge is cut or jagged (Fig. 71). 40. When leaves are deeply and regularly cut, the 66 Figs. 56-58. Base of leaves; 56. Auriculate; 57. Sagittate; 58. Hastate, Figs. 59-66. Apex of leaves: 59. Acuminate; 60. Acute; 61. Obtuse; 62. Truncate; 63. Emarginate; 64. Obcordate; 65. Cuspidate; 66. Aristate. THE LEAF. 85 divisions are called lobes. If the incisions extend more than halfway from the margin to the midrib, the leaf is 67 68 said to be cleft (Fig. 72); the number of segments are indicated by the terms bifid (two-cleft), trifid (three- cleft), multifid (many-cleft), etc. If the divisions extend almost to the midrib, the leaf is said to be parted; if they extend quite to the midrib, the leaf is divided; and thus a simple leaf, or one with lamina in a single piece, is converted into a compound leaf, that is, one with the blade divided into several parts (Fig. 73). Each of the latter is called a leaflet (Fig. 73, Uff), and the stem or mid- rib, which supports the leaf lets, is called the rachis (Fig. 73, rach). 41. Corresponding with the pinnate and palmate type of venation, there are pinnately and palmately compound 72 Figs. 67-71. Margin of leaves: 67. Serrate ; 68. Dentate; 69. Crenate; 70. Un- dulate; 71. Incised. Fig. 72. A Cleft leaf. Fig. 73. A divided, z.e, compound, leaf of the rose: 7/7, leaflets; rach, rachis; sti, stipules. 86 ORGANOGRAPHY. leaves. The pinnate leaves have the leaflets or pinne arranged on each side of the rachis. If-the leaflets are in pairs throughout, the leaf is said to be abruptly-pinnate (Fig. 74); if a single leafiet terminates the rachis, the leaf is said to be odd-pinnate (Fig. 73). Palmate (some- times called digitate) leaves have the leaflets borne on the extreme tip of the leaf-stalk (Fig. 75). 42. The leaflets themselves may be divided, which is expressed by the terms bi-pinnate (twice pinnate, Fig. 76), or thrice pinnate. When the leaf is several times \ compound, it is called de-compound. Of numerous other forms not yet men- tioned, the following are conspicuous. Per- foliate (Lat. per, through ; folium, leaf), in which the stem ap- {\ pears to pass through — the leaf near its base 77, Fig. 74. An Abruptly-pinnate leaf. Fig. 75. A Palmate (or Digitate) leaf. Fig. 76. A Bi-pinnate leaf. Fig. 77. A Perfoliate leaf, THE LEAF, 37 (Fig. 77), as in the Uvularia. In the Honeysuckles the opposite leaves are sometimes united at their bases, rendering them con- nate-perfoliate (Fig. 78). The « leaves of the Iris are equitant, that \ is, straddling over each other. Several kinds of leaves have no distinction of blade and petiole; as the sword-shaped, ensiform (Lat. ensis, sword), leaves of the Daffodils; the needle-shaped, acicular (Lat. acus, needle), leaves of the Pines (Fig. 29) ; and the scale-shaped, squamose (Lat. squama, scale), leaves of the Junipers. If petioles become laminoid, or ex- panded like a blade, and take the place of the latter, they are called phyllodia. 43. The stipules are sometimes free, leaf-like append- ages, as in the Pea (Fig. 79), and perform the ordinary function of leaves; in Galium they are interpetiolar, and as large as the leaves and exactly resemble them, so that the leaves are usually said to be whorled; but in reality they are opposite, the two intermediate leaves on each side being free stipules. Ordinarily, however, the stipules are very much reduced in size, as in the Bean; sometimes they take the shape of bristles or prickles, as in the Locust (Fig. 80). In the Smilax they take on the shape of tendrils (Fig. 81). When united to the base of the Fig. 78. A Connate-perfoliate leaf. Fig. 79. Leaf of the Pea, with large, /ree stipules (stip). 38 ORGANOGRAPHY. petioles, as in the Rose and Clover, they are said to be adnate (Fig. 73, stip). The stipules of the Tulip-tree serve as bud-scales, falling off soon after the leaves unfold. 44. In the Dock and the Buckwheat family the stipules unite and form a sheath around the stem (Fig. 82), which is called Ochrea. If the outer margins only unite, as in the Buttonwood, a double stipule opposite the leaf is formed. If the inner margin only unite, as in the Pondweed (Potamogeton), the double stipule is situated in the axil of the leaf. The sheaths of the grasses represent the petiole, for they bear the blade at their summit; but the small appen- dages, commonly found at the top of the sheath, called a ligule (Fig. 83), is of the nature of a stipule. Fig. 80. Spinous stipules (s¢. s#i4) of the Locust. Fig. 81. Tendril stipules of Smilax. Fig. 82. An Ochrea, or Sheathing stipule, of Polygonum. Fig. 83. Grass leaf, with the ligule (/ég’) representing a stipule. THE FLOWER. 39 45. The Flower.—If a leafy shoot be reduced in length, the leaves will be brought close together; if the internodes (portions of the stem between the joints) are want- ing entirely, the leaves will be in whorls, or form a ro- sette. If now these 84 leaves undergo cer- tain changes in form and function, a Flower will be formed. This change or modification of one part or organ into another, is called metamorphosis (Gr. meta, beyond ; morpha, form); the flower is a metamorphosed branch, and the different organs are modified leaves (Fig. 84). Proofs of this are found in the partial or complete reversion of floral organs back into ordinary leaves; indeed, numerous intermediate forms may readily be found which form a gradual transition from a foliage leaf to the most highly differentiated organ of the flower. 46. The axis and leaves, belonging to or near the flower- cluster, undergo modifications to form peduncles and pedicels, and bracts and bractlets. Thestem, or stalk, which sueEons a flower-cluster, or a single aos If the peduncle is wanting, that is, if the flower is inserted directly on the stem, it (the flower) is said to be sessile. When the peduncle arises from the ground, it is called a scape. Fig. 84. Transformation of petals into stamens. Fig. 85. Flowers supported by pedicels (Jed), which are branches of the peduncle (faz): dr, bracts; drt, bractlets. 40 ORGANOGRAPHY. The minute branches of the peduncle, or slender stalks which support the individual flowers, are called pedicels (Fig. 85, ped). ( 47. The bracts are generally dimin- [i utive leaves which subtend the flower- Lf cluster, or from whose axil the flower stem proceeds (Fig. 85, br). The sec- ondary or small bracts on the pedicels are called the bractlets (Fig. 85, drt). They have generally lost the ordinary function of leaves, and in some cases become highly colored like the flower, as in the Painted-cup (Castelleia), etc. If a single, enlarged bract enclose the flower-cluster, it is called a spathe (Tig. 86). If the bracts are numerous and form a conspicuous cup under the flowers, or an imbri- cated covering around a head of flowers, they form an involucre (Fig. 87,in). The axis of an elongated flower- cluster is called the rachis. When the axis is short, or abortive, so that the flowers are crowded into a head, it is called the receptacle (Fig. 87, rec). 48. Inflorescence (Lat. flos, flower) is the mode of flowering, or the situation and arrangement of the blossoms on the plant. If the flowers develop from lateral buds, the inflorescence is called indeterminate, for the shoot, termi- nated by a bud, may continue to grow in length. If the flowers develop from terminal buds, the Fig. 86. Spathe of the Indian Turnip. Fig. 87. Reflexed involucre (zz) and receptacle (vec) of the Dandelion. : THE FLOWER. AL inflorescence is determinate, because the length of the axis is thereby determined; it cannot grow longer. The indeterminate inflorescence is also centripetal, that is, the outermost flowers (when the cluster is level-topped), or the lowest on the stem, open first, and those higher follow in recular succession, until finally the one in the centre or at the top expands. Examples are furnished by the Lily of the Valley, Currant, Plantain, Shepherd’s-Purse, etc. The determinate inflorescence is centrifugal, inasmuch as the flowering begins in the centre or top and proceeds outwards 88 89 90 91 or downwards. This is exhibited in the Chickweed, Dian- thus, Hydrangea, ete. 49. The following are varieties of indeterminate inflores- cence: Raceme, Corymb, Umbel, Spike, Spadix, Catkin, Head, and Panicle. The raceme has the pedicellate flowers scattered on an elongated axis (Fig. 88). The corymb is the same as a raceme, with the lower pedicels elongated so as to make the flower-cluster Jevel-topped (Fig. 89). In an umbel the axis is reduced, and all the pedicels proceed from a common point (Fig. 90). The Figs. 88-91. Diagrams, illustrating forms of inflorescence: &8. Raceme; 89. Corymb ; 90, Umbel; 91. Spike. 42 ORGANOGRAPHY. a spike is similar to a crowded raceme, with the flowers ses- sile (Fig.91). Twospecial forms of the spike have peculiar names, namely, the spadix (Fig. 86), which is fleshy (and commonly sur- rounded by a spathe); and the catkin, or ament, which is scaly (Fig. 92). The head differs from a spike in that the axis is re- duced, crowding the flowers into a head-like cluster (Fig. 93). A panicle is an open and more or less compounded raceme or corymb (Fig. 94). 50. The cyme isa determinate or definite flower-cluster, with a flat or convex top. It resem- bles the corymb somewhat, except that in the latter the flow- ering is centripetal, while in the cyme it is centrifugal (Fig. 95). A crowded cyme is called a fascicle. Many of the clusters are often compound, as compound umbels, compound cymes, etc. The two classes of inflores- cence may be repre- sented in one and the same plant; thus the Mint Family has cymes or fasci- . cles, which are cen- trifugal in their flow- ering, but these are a Fig. 92. Catkin of the American Hazel. Fig. 93. Head of Clover-flowers. Fig. 94. Diagram of a Panicle. Fig. 95. Diagram of a Cyme. ° THE FLOWER. 43 generally composed of spikes or racemes, which are centri- petal in their flowering. 51. The flower is that organ of the plant which is designed for the production of seed, and thereby the continued existence of its kind. In a complete flower, such as the Buttercup, Rose, Phlox, etc., there is externally the calyx (Fig. 96, ca), or cup-like portion, which consists of several parts, either distinct or united, which more or less resemble ordinary foliage leaves (Fig. 96). Each leaf, or portion of the calyx, is called a sepal; within this whorl of leaves forming the calyx is a second whorl, either of distinct or more or less united parts, called the corolla (Fig. 96, cor). This is commonly the most showy part of the flower. Its component parts are called petals, and they usually depart farther from the ordinary form and texture of foliage leaves than do the sepals. 52. Within the corolla are slender bodies called stamens (Figs. 96,101, etc). They sometimes revert to petals or sepals (Fig. 84), showing that they are also modified leaves. These bodies are sometimes excess- ively numerous; and when few, are rarely less in number than the parts of the corolla or calyx. Within these, and occupying the central part of the flower, are the pistils (Figs. 96, 101, etc.); in the lower enlarged part of which (called the ovary) the seeds are produced. The pistils, like the stamens, may be numerous, but are very often reduced to one or two. It is very common for the pistils to revert to ordinary green foliage leaves. There can be no production of seed without both stamens and pistils, and for this reason Fig. 96. A Flower: ca, calyx; cor, corolla; iz, involucre. 44 ORGANOGRAPHY. they are together called the essential organs of the flower. The calyx and corolla may or may not be present . Without directly influencing the pro- ‘duction of seed. When present, they surround the essential organs and pro- tect them, hence they are called pro- tecting organs. They are also called the perianth (Gr. peri, around; anthos, flower). 53. A flower with the four parts present is called a com- plete flower; but if one or more of the parts are absent, the flower is said to be incomplete. If the essential organs are present it is called a perfect flower. Those with stamens only (called staminate flowers), and those with pistils only (called pistillate flowers), are imperfect. If the parts are alike among themselves,—that is, all the sepals alike in shape and size, all the petals alike in shape and size, and all the stamens alike in shape and size,—the flower is said to be regular (Fig. 97). If this likeness in shape and size does not obtain in any one set of organs, the flower is said to be irregular (Fig. 98). If the petals, sepals, and sta- mens are of the same number, or the latter twice or thrice that number, the flower is said to be symmetrical; butif the number is not the same in each whorl, the flower is unsymmetrical. 54. If the relative in- sertion of the floral parts be examined, two types will be found to prevail. In the one case each petal is inserted directly in front of or within a sepal, and each Fig. 97. Kalmia blossom, a regular flower. Fig. 98. Flowerof Lobelia, irregular. THE FLOWER. 45 stamen directly in front of or within a petal; and the parts are said to be opposite (Fig. 99). But in the other case the petals are in front of or within the spaces between, that is, alternate iN S 3 with the sepals, and the stamens NS 2 NS) oy alternate with the petals; then the parts of the flower are said to be alternate (Fig. 100). When the parts of the flower, espe- cially of the calyx and corolla, are each three in number, the flower is said to be three-parted; and it is generally found that three-parted flowers are borne on plants which have parellel-veined leaves. If the parts are in 4’s or 5’s, the flowers are respect- ively four or five-parted ; such flowers gen- ae erally accompany netted-veined leaves. sf ~"eds 5x, When the sepals are free, or dis- 100 101 to be polysepalous (Gr. polus, many) ; and when the petals are free, the corolla is polypetalous (Fig. 101). The sepals may be united edge to edge, so that only their upper ends are free, by which the number form- ing the cup or calyx may be deter- mined. The calyx in such case is ( said to be monosepalous (Gr. monos, one), or gamosepalous (Gr. gamos, union). When the petals are uvited, the corolla is monopeta- lous, or gamopetalous (Fig. 102). This union of similar parts or cohe- sion, as it is called, gives rise to a Fig. 99. Diagram of a flower with parts opposite. Fig. 100. Diagram of a flower with parts alternate. Fig. 101. A polysepalous and polypetalous flower, Fig. 102. A Rotate corolla. 46 ORGANOGRAPHY. variety of forms of the calyx and corolla; prominent |... among which are: Rotate, Salverform, Cam- 2J panulate, Funnelform, Tubular, Labiate, and Ligulate. 56. A rotate (Lat. rota, wheel), or wheel- shaped calyx or corolla, ig one in which the tube is very short or wanting, and the lobes spread at once (Fig. 102). In the salver- form corolla, the spreading limb or border is raised on a narrow tube, and forms a right angle with the latter (Fig. 103). The campanulate (Lat. campanula, bell) denotes a bell-shaped calyx or corolla Wy (Fig. 104). In the funnelform, the tube is "\ narrow below, but gradually spreading above like a funnel. The tubular form spreads scarcely any above (Fig. 106). The two upper petals "may unite closely and form a 104 kind of upper lip, and the three lower ones unite to form a lower lip (Fig. 105.) In such case the corolla is labiate (Lat. dabiwm, lip). The calyx may also be labiate, or two-lipped. 57. If a flower-head of a Sunflower be examined, it will be found to consist of numerous florets, with tubular corollas interspersed with the bristles or chaff (Fig. 106), and a row of marginal flowers called ray flowers; these ray flowers have strap-shaped corollas (Fig. 106, Zig), which are called ligulate (Lat. ligula, tongue). A curious shape is presented by the Pea or Bean (Fig. 107). The corolla Fig. 103, A Salverform corolla, Fig. 104. A Campanulate corolla, Fig. 105. A Labiate corolla of Toad-flax. THE FLOWER. 47 is polypetalous; very irregular and resembles more or less remotely a butterfly, and for this reason it has received the name Papilionaceous (Lat. papilio, butter- fly); the upper and larger petal is called the banner, or vex- illum (Fig. 107, v); the two side petals are called the wings, or ale (Fig. 107, a); and the two anterior ones, generally cohering slightly (and enclosing the stamens and pistil), are called the keel (Fig. 107, k). The flowers of the Cress, Mustard, Cabbage, etc., have four petals, arranged two and two opposite, somewhat like a cross, and they are said to be cruciform (Lat. crux, cross; Fig. 108). 58. A conspicuous irregularity in the flower is caused by the production of appendages of various kinds, One petal in the Violet is prolonged so as to , form a spur; this e “organ is tubular, ~ and generally con- tains Nectar, or sweet substance secreted by the aoe flower. One species of Dicentra at is two-spurred. All the petals of Fig. 106. A head of flowers of Heliopsis: z#, involucre ; ¢.f, disk-flowers ; Zig, ray-fluwers ; ch, chaff; ach, achemia. Fig. 107. A Papilionaceous flower of Pea: v, vexillum; a, wings; Z, keel. Fig. 108. A Cruciform corolla. 48 ORGANOGRAPIIY. the Columbine have spurs. Sometimes there is only a gentle swelling or blunt, outward projection (as in Adlu- mia), which is denoted by the word saccate. Sometimes se- pals or petals are eared or crested; or they have, like the Pink, a projection (corona) at the point where the claw or narrow part of the petal joins with the spreading lobe or limb. 59. When there is no adhe- sion or growing together of the calyx and corolla, the former is plainly inserted below the points of insertion of the corolla, stamens, and pistils. In such case (Fig. 109), the calyx is said to be free or inferior; or the calyx and corolla are said to be hypogynous (Gr. hypo, under; guna, pistil). The cohesion may be to the extent shown in Fig. 110, where the petals and stamens are inserted on the calyx-tube. The petals are then said to be perig- ynous (Gr. peri, around), though the calyx is free. The calyx-tube may be consolidated with the lower part of the pistil or ovary, when it is said to be adherent or Superior ; in this case the parts appear to be inserted upon the pistil (ovary), and are therefore said to be epigynous (Gr. ept, upon; Fig. 111). Ifthe adhesion does not extend so far up (half-way), the calyx is said to be half-superior. Figs. 109-111. Diagrammatic sections of flowers ; 109, Hypogynous ; 110. Perig- ynous; 111. Epigynous. THE FLOWER. 49 6o. The arrangement of the sepals and petals in the flower-bud, or zestivation (Lat. estas, summer), may best be came seen in transverse sections of the ( wal) Econ Cin) bud when it is about ready to ex- Su KF Xpand. If the pieces do not over- 112 413 14 lap each other, but simply meet edge to edge, the estivation is valvate (Fig. 112). Exam- ples are furnished by the calyx of the Basswood and the Mallow, and the corolla of Grape and Virginia Creeper. In the valvate calyx, or corolla, if the edges turn inwards, it is said to be induplicate; if outwards, it is said to be reduplicate. In the corolla of the Potato is an example of the former; and in the sepals of the Althea of the latter. In case the parts overlap each other (as in the corolla of Mallows), so that one edge of each is covered, and the other not, the estivation is convolute (Fig. 113). When the overlapping is such that some pieces are wholly inside and others wholly outside, like the shingles on a roof (as in the corolla of the Basswood), the sxstivation is imbricate (Lat. imbrezx, tile; Fig. 114). 61. The stamens consist of two parts (Fig. 121), namely, the filament (Lat. filum, thread), or slender stem; and the anther, or en- larged upper end. That portion of the filament between the anther lobes is called the connective. The filament is not an essential part, and when wanting, the anther is sessile. When the fila- ments are united into a tube surrounding the pistil, as in the Mallow (Fig. 115), they are said to be Figs. 112-114. Diagrams illustrating xstivation: 112. Valvate; 113. Convolute; 114 Imbricate, Fig. 115. Monadelphous stamens (/2/. #zoz.) in Mallow. 4 50 ORGANOGRAPHY. monadelphous (Gr. monos, one; adelphos, brotherhood). If they are united into two sets, as in Dicentra, they are diadelphous; if in three sets, triadel- phous; and soon. When the anthers are united into a tube, as in the Composite family (Sunflower, Dandelion, etc.), they are said to be syngenesious (Gr. syn, with ; genesis, birth). If a transverse section of the anther be made (Fig. 116), two or four cavities, called cells, will be seen, and these are filled with a yellow dust, which, on examination with the microscope, proves to be small, round bodies, called pollen (Fig. 117). Each pollen grain has two coats: the outer, thicker and often orna- mented; the inner, more delicate and elastic. 62. The opening of the anther at maturity, for the discharge of the pollen, is called dehis- cence. This commonly takes place by a line along the whole length of each cell (Fig. 118). In the Sassafras, Barberry, etc., the opening is by a lid or valve (Fig. 119). In the Azalea, Pyrola, etc., the pollen escapes by a pore at the top of the anther (Fig. 120). As regards the attachment of the anther to the filament, it may be innate, or inserted by its base on the top of the filament (as in Fig. 121); or adnate, when attached by & one face its whole length (Fig. 122). It is ver- satile when inserted near its middle point to the top of the filament, 1s i920 1 12 123 so that it may swing Fig. 116. Transverse section of an anther, Fig. 117. A pollen grain. Figs. 118- 120. Dehiscence of anthers ; by splitting longitudinally ; by lids or valves; by pores. Figs. 121-123. Attachment of anthers; 121, Innate; 122. Adnate; 123. Versatile. an One fie THE FLOWER. 51 loosely (Fig. 123). If the anther is attached to the side of the filament towards the pistil, it is said to be introrse; if from it, extrorse. said to be monandrous (Gr. monos, one; ander, stamen); if two stamens are present, it is dian- drous; if three, triandrous; if four, tetran- drous; andsoon. If the stamens are numerous or indefinite, the flower is polyandrous. In the Labiate family often two of the stamens are long and the other two short; they are then called didyna- mous (Gr. di, two; du- namis, power, strong). In the Crucifer family four Y stamens are long and two short (Fig. 124), and are called tetradynamous (Gr. tetra, four), As re- gards the insertion of the stamens, they are hypog- ynous when attached below the pistils (Fig. 109); perig- ynous when attached to the calyx-tube sur- rounding the pistil (Fig. 110); and epigynous when situated with the sepals on the ovary (Fig. 111). They are epipetalous when attached to the corolla (Fig. 125). 64. The pistil (Fig. 126) consists of three \@ parts: namely, the ovary (Fig. 126, ova), or lower enlarged part which contains the ovules or seeds; the style (Fig. 126, sty), or slender part above Fig. 124. Tetradynamous stamens. Fig. 125. Flowers, with stamens on the corolla (epipetalous). Fig. 126, A pistil: ova, ovary ; ove, ovules; sty, style; stig, stigma; f/a, placenta. 52 ORGANOGRAPHY. the ovary; and the stigma (Tig. 126, stig), the more or less enlarged upper end of the style. The style may be wanting, which renders the stigma sessile. According as the pistil, or carpel, as it is sometimes called, is formed of a single leaf or of several leaves, it is simple or compound. In a simple pistil, formed by a single leaf folded edge to edge, the seeds are borne on the part of the inner wall, which corresponds to the line of union of the edges, and is called the placenta (Fig. 126, pla). If two placente are present, they must have resulted from the union of two leaves, edge to edge; if three placente, from the union of three leaves, etc. Therefore the presence of two or more placentz is proof of a compound pistil. The number of styles generally corresponds to the number of leaves entering into the formation of the carpel. 65. Compound pistils may 127 128 have a single cell, or they may have many cells. When the latter have simply united with each other, edge to edge (Fig. 127), there will be but one cell, and the placente, or seed-bearing lines, will be situated on the ovary wall, as in the simple pistil; that is, they will be parietal (Lat. paries, wall). If each separate carpellary leaf unites edge to edge, and then all the carpels join (Fig. 128), the ovary will have as many cells as there were carpellary leaves, the seed-bearing lines will be crowded to the centre and form central placentee. The dissepiments or walls which separate the cells from one another may become obliterated, leaving the seed-bearing column in the centre of a continuous or one-celled cavity, Figs. 127, 128. Diagrammatic sections of compound ovaries : 127. One-celled ovary, parictal placentz ; 128. Many-celled ovary, placente central. THE FLOWER. 53 and thus a free central placenta is formed (Fig. 129). Examples of this are found in the Purslane, Chickweed, Pinks, ete. 66. The number of pistils in a flower is ex- pressed by the Greek words: monogynous, meaning one pistil; digynous, meaning two 129 pistils; trigynous, meaning three pistils; tetragynous, meaning four pistils; pentagynous, meaning five pistils; polygynous, meaning many pistils. The ovary and calyx- tube may be united, when the former is said to be adher- ent, or inferior (Fig.111). If the adhesion extends half r t t t pol fus me MICS pocuun., way up, the ovary is said to be half-inferior. If there is no ad- hesion of the ovary with other parts, it is said to be free, or su- perior (Fig. 109). The ovules, or small bodies which are to become seeds, are enclosed by the pistil; the latter is, therefore, said to be angiospermous (Gr. angios, ves- sel; sperma, seed). 67. In the Pine family the ovules lie exposed in the cone, on the upper surface of the base of the scales. The scale is, therefore, the pistil, and it is said to be gym- nospermous (Gr. gymnos, naked; sperma, seed). If ovules, either of gymnospermous or angiospermous pistils, be examined, they will be found to consist of a central Fig. 129. Diagrammatic section of compound ovaries : One-celled, placenta free, central. Fig. 130. Diagrammatic section of an ovule: fo/ ¢u, pollen-tube; zc, micropyle ; oz. zz, outer integument; zz. 7z, inner integument ; em. s, embryo-sac; nuc, nucleus. 54 ORGANOGRAPHY. part, called the nucleus, surrounded by one or two integ- uments (Fig. 130, in). These integuments do not close entirely above, but leave a small orifice, called the micro- pyle (Fig. 130, mic). This is for the entrance of the pollen-tube (Fig. 130, pol tu), which grows from the pollen grain that has been transported from the anther to the stigma. 68. In the upper part of the nucleus of the ovule is the embryo-sac (Fig. 130, em.s), in which the embryo of the seed is to be developed. This development, however, does not take place till the ovules become fertilized, that is, until the tube emitted by the pollen grain grows from the stigma down through the style, enters the micropyle, and reaches the embryo-sac, where the contents of the grain or tube passes by osmosis into the embryo-sac. Unless, there- fore, the pollen finds transport from the anther to the stigma, there will be no production of seed. This transfer- ence of the pollen is called pollination, and many contri- vances and agencies exist to effect it, the most important of which will now be mentioned. 69. Pollination and Fertilization.—When both the essential organs, stamens and pistils, are contained in one and the same flower, as the Rose, Lily, Buttercup, Mint, and Grass, it is called an hermaphrodite flower. Many plants possess, either in the same cluster or on different branchlets, both fertzle (pistillate, that is, with pistils, but no stamens) and sterile (staminate, that is, with stamens, but no pistils) flowers, and they are said to be monce- cious (Gr. monos, one; otkos, house), such as the Oaks, Hickories, Alder, Corn, Nettle, etc. Others have the tertile and sterile flowers on different trees, as the Willows, Pop- lars, Ash, Hemp, ete., and they are called dicecious (Gr. THE FLOWER. 55 di, two; otkos, house). In monecious and dicecious plants it is evident that the transport of the pollen from the staminate to the pistillate flowers must in some way be effected in order to accomplish fertilization. Even in hermaphrodite flowers it is found to be a rare case that the pollen, wholly unaided, falls on the stigma of the same flower. 7o. When the pollen of a flower is applied to, and acts on, the stigma of the same flower, the process is called close-fertilization, or self-fertilization. But if the pollen of one fluwer is applied to, and acts upon, the stigma of a different flower, it is called cross-fertilization. It would naturally be expected that in hermaphrodite flowers self-fertilization would almost invariably obtain. So it was taught until very recently. Now it is known that cross- fertilization is the rule, and self-fertilization the exception. In fact, there is in the majority of cases something in the structure of the flower to prevent self-fertilization. Many plants, as the Oxalis, Violet, etc., have two sets of herma- phrodite flowers—a showy form, in which cross-fertilization ‘occurs, and an inconspicuous form, where close-fertilization necessarily takes place. 71. When the transport of the pollen is effected by the wind, the flowers are said to be anemophilous (Gr. anemos, wind; philos, loving). Such are the Pines, Oaks, Hickory, Walnut, Alder, Grasses, Sedges, Hemp, Hops, etc. They are characterized by the production of an enor- mous quantity of pollen. This insures the contact with the stigma of at least a small portion of the pollen. It is light, dry, incoherent, and readily transported great distances, sometimes forming “showers of sulphur.” The flowers are mostly greenish, or of dull colors, and inconspicuous. The 56 ORGANOGRAPHY. stigmas are generally large, often furnished with hairs or dissected into plumes (Fig. 131) for the retention of the grains that may come in contact with them. The anthers are often suspended on capillary filaments, so as to be more directly exposed to the action of the wind. 72. When pollination is effected by insects, the flowers are said to be entomophilous (Gr. entomon, insect; philos, loving). In these the amount of pollen produced is not so great, there being but little waste as compared with the loss when transported by the wind. It is not so dry and incoherent as in the anemophilous flowers; the grains are generally moist or slightly viscid, often - provided with projections or entangling threads. In the Orchids and Milkweeds the pollen is in masses, supplied with viscid pedi- cels (Fig. 148). All these contrivances tend _ to insure the adherence of the pollen grains or masses to the head, legs, or body of the insects which visit the flowers, and thus effect the transportation cf the pollen to the stigmas of other flowers. Such flowers are further characterized by the possession of a large, showy perianth, or of odor, or by the secretion .of nectar; or they may furnish all these attractions combined. 73. Of the special adaptations in hermaphrodite flowers, to insure cross-fertilization, dichogamy (Gr. dichos, asun- der; gamos, union) is an important one; it means that the stamens and pistil of the same flower do not come to matu- rity at the same time, hence self-fertilization is impossible. The flower is proterandrous (Gr. protos, first; andres, stamens) when the anther ripens and discharges the pollen Fig. 151. Plumose stigma of a grass-flower (Poa pratensis). THE FLOWER, 57 before the stigma reaches maturity. If the stigma is in a receptive condition before the pollen escapes, the flower is proterogynous (Gr. guna, pistil). Among the anemo- philous flowers the common Plantain furnishes an example of Proterogyny, The long, slender, hairy stigmas may be seen protruding from the unopened perianth while the anthers are yet enclosed. Only pollen from other flowers, therefore, can effect the fertilization. Later the stigmas wither, and the corolla expands; the four anthers now appear supported on long, delicate filaments, and their pollen is carried to stigmas of other Plantain-flowers which may have a synchronous maturity. am 74. A Proterogynous example i) ds among entomophilous flowers is fur- CM ! nished by the Serophularia. The flow- (2% ry ers are visited by bees for the nectar, which is secreted by glands at the 132 bottom of the corolla. The lower lobe of the irregular corolla serves as a landing-place for the bees. The mature pistil projects, as seen in Fig. 132, when the flower first opens; and fertilization now takes place, the pollen coming from another flower of the same sort. The position of the unripe stamens at this time is not seen in the figure, for the filaments are curved and the unripe anthers are deep down in the corolla. A day or two later the anthers, now ma- ture, appear at the mouth of the corolla, as is shown in Fig. 183. By this time the stigma, previously fertilized, is no longer in a receptive condition, and lies half-withered on the lower petal. Bees, visiting the flower, would come in contact with the anthers, and the pollen grains that adhered Figs. 132,133. Proterogynous flowers of Scrophularia nodosa: 132. First stage: Stigma mature; 133. Second stage: Anthers mature: J, pistil ; az, anthers. 58 ORGANOGRAPHY. to them would be carried to the next Scrophularia visited by them, and the pistil, if ripe, would receive and be fer- tilized by them. 75. As an example of proterandrous flower, may be mentioned “Clerodendron Thompsonie, a Verbenaceous, tropical African climber, now common in conservatories. The adaptations in this flower (which we indicated long ago) are exquisite. The crimson corolla, and bright, white calyx in combination, are very couspicuous. The long fili- form filaments and style, upwardly enrolled in the bud, straighten and project when the corolla opens; the stamens” remain straight, but the style proceeds to curve downwards and backwards, as in Fig. 184. The anthers are now dis- charging pollen; the stigmas are immature and closed. Fig. 135 represents the flower on the second day, the anthers effete and the filaments recurved and rolled up spirally, while the style has taken the position of the fila- ments, and the two stigmas, now separated and receptive, are in the very position of the anthers the previous day. The entrance, by which the proboscis of a butterfly may Fig. 134, 135, Proterandrous flowers of Clerodendron Thompsonia ; 134. First stage: Anthers mature; 135, Second stage: Stigma mature, THE FLOWER. 59 reach the neetar at the bottom, is at the upper side of the orifice. The flower cannot self-fertilize. A good-sized insect, flying from blossom to blossom and plant to plant, must transport pollen from the one to the stigma of the other.” —(Gray.) 76. The composite flowers, such as the Rudbeckia, Heliopsis (Fig. 136), Sunflower, etc., are additional exam- ples of proterandry. The anthers are syngenesious, and discharge the pollen early, which is pushed out of the tube by the elongating pistil (Fig. 136, ZZ, p). The latter is not as yet in a receptive condition, and more- over the pollen can- not be applied to the stigmatic surfaces, for they are on the inner sides of the forks or branches of the tip of the style. These do not spread until the pistil has acquired its full length, and then curv- ing outwards, the adjacent pollen is still prevented from access to the stigma (Fig. 136, IZJ, st). The conspicuous ray-flowers (Fig. 136, 4g) doubtless serve for the attraction of the many visiting insects, and they, by their more or less hairy bodies, convey the adhering pollen (Fig. 136, IV) from some flowers to the exposed stigmas of others; and thus cross-fertilization is effected. Other proterandrous Fig. 136. Heliopsis levis: I, Section of head of flowers; //, Floret immature; Z7I, Floret, with mature stigma; JV, Pollen grain; z#, involucre; @.f, disk-floret ; lig, ray-flowers; ach, achenia; ch, pale or chaff; Z, pollen; s¢, stigma. 60 ORGANOGRAPHY. flowers are the Gentians, Epilobium, Campanula, Parnassia, Lobelia, ete. The anthers in Lobelia are like those in the Sunflower family, that is, ; we, syngenesious, or united | by their anthers forming me \'ih a tube around the upper “xs. portion of the style. The bl 1372 pollen is discharged while the style is yet so short (Fig. 137) as to be concealed deep down in the tube. As the stigma approaches maturity, the style elongates and pushes the pollen out before it; the mouth of the tube is so situated that insects entering the throat of the corolla, for the purpose of getting nectar, would necessarily brush the pollen onto their body from the end of the protected stigma (Fig. 137a). The stigmatic sur- face finally becomes exposed (Fig. 138). It is evident from the description and figures that self-fertilization is impossi- ble; and cross-fertilization by the insects, which transport the pollen from flowers in the first stage of maturity to those in the second stage, must take place. 77. Dimorphism (Gr. di, two; morpha, form) denotes two kinds of hermaphrodite flowers of the same species. It is often an adaptation for intercrossing. An example is furnished by the Houstonia. One set of flowers has long stamens and a short pistil (Fig. 189), and the other set has short stamens and a long pistil (Fig. 140). Figs. 137, 138, Proterandrous flowers of Lobelia syphilitica: 137. First stage: Anthers mature; 138, Second stage: Stigma mature; az, anthers; //, filament; st, stigma; 4, hairs, Figs, 137a, 138a: Stigma slighUy magnified. THE FLOWER. 61 A bee visiting the different flowers would brush some part of the body against the anthers of the long stamens, and another part against the anthers of the short stamens; and these same parts (which, of course, would have pollen adhering to them) coming in contact with long and short pistils respectively, the pollen of one flower would in each case be applied to a stigma of another flower; or, in other words, cross-fertilization would necessarily result. It is found, besides, that the pollen grains of the two sets of stamens are of different size, and each less active upon its own stigma than upon the stigma of another flower. In some genera three sets of flowers with sta- mens and pistils of differing lengths exist (trimorphism), evidently designed for intercrossing. 78. There are other adaptations for cross-fertilization besides dichogamy and dimorphism. An interesting case is furnished by papilionaceous flowers ; for example, the Pea (Figs. 141-143). The ten stamens and single pistil are enclosed within the keel (Fig. 141), There are hairs on the style below the stigma, and these loosely retain the pollen which is discharged early by the anthers, the latter remaining in the keel. When a bee alights on the wings (Fig. 142, a) and keel (Fig. 142, k) they are together Figs. 139, 140. Dimorphic flowers of Houstonia; 139, Pistil short; 140. Pistil long, 62 ORGANOGRAPHY. pressed downwards, and the pistil protrudes in consequence (Fig. 143, A). The stigma strikes the abdomen of the bee, and the style also brushes against it. When the bee aie visits the next flower, the stigma of that strikes the abdomen as before, but it has been dusted “with pollen from the previous flower, and of course a portion of it is retained by the stigma, thereby effecting cross-fertiliza- tion. In like manner pollen from that flower is carried to the next, and so on. 79. Aslight variation from the foregoing is seen in the Bean blossom, where the keel is coiled into a snout (Fig. 144). Within this are the stamens, also the pistil, with an oblique stigma and hairy style (Fig. 145), the latter loosely retain- ing the early discharged pollen. When a bee, in alighting to search for nectar, presses the wing-petals downwards, the stigma and hairy style, loaded with pollen, protrude, strik- ing the front part or side of the insect. Therefore visiting a succession of flowers the bee transports pollen Figs. 141-143. Papilionaceous flower of the Pea: 141. The flower entire; 142. The alz, or wings, removed, exposing the keel; 143. A, the keel depressed, causing the stigma to protrude; 2, the diadelphous filaments; v, vexillum; a, ale; %,keel; Ju, filaments. THE FLOWER. 63 from one to another. In the Kalmia blossom the anthers of the ten stamens are lodged in cavities in the co- rolla, and the filaments are curved backwards as the flower expands (Fig. 146). Bumble-bees, hovering over the flowers, searching for nec- tar, liberate the stamens by occa- sional contact, which, in springing back straight, discharge the pollen from pores at the top of the anthers (Fig. 147). <= Some of the pollen grains which strike ff\ the under side of the bumble-bee and adhere to it, will, when the next flower is approached, be deposited on its stigma, thus bringing about cross-fer- tilization. 146 ut 80. The most varied and wonderful contrivanées for cross-fertilization are found in the family of Orchids (Fig. 148). The stamens are ss reduced to one, and this is united in a column with the pistil, indicated by the term gynandrous (Gr. guna, pistil; andres, stamens). The pollen in each anther- cell is united into a mass, and furnished with a little stem or caudicle, which has avery viscid disk (Fig. 148, TJ, IV, d). These two disks are so placed that when an insect visits the flower, and thrusts its proboscis into the spur for the nectar (as shown by the arrow, Fig. Fig. 144. The coiled tip of the keel of a Bean-flower. Fig. 145. The terminal portion of the style of the same flower. Fig. 146. Flower of Kalmia latifolia. Fig. 147. One of its stamens discharging pollen, slightly magnified. Fig. 148. Orchid flower: J, flower entire; //, some parts removed; //J and JV, pollinia attached to a lead pencil; @, disk; 4, pollinia; s¢, stigma; P.S., anther or pollen- sac; cl, caudicle; /// and ZV, slightly magnified, 145 64 ORGANOGRAPHY. 148, IZ), they will touch and adhere to its head, and be dragged from their places when the insect departs (Fig. 148, HT). The pedicels dry quickly, and curve downwards (Fig. 148, IV); when, therefore, the insect approaches another flower of the same kind, the pollen masses, or polli- nia, as they are called, strike against its viscid stigma, and a portion of the pollen is retained. The pollinia of this flower are in the same manner transferred to the next visited, and soon. When the access of insects is prevented, no seeds are produced, showing that self-fertilization is impossible. 81. Many tropical plants cultivated in the conserva- tories invariably fail to produce seed. The cause of this is to be found in the fact that the tropical insects which alone can effect their pollination are not present. It is not at all seldom that only a certain species, or, at most, only a few species, of insects can fertilize a particular kind of flower, as in the case of bumble-bees and Red Clover. Many of the adaptations for cross-fertilization, it should be remembered, do not absolutely prevent self-fertilization, so that if insects fail to visit the flowers a few seeds may, nevertheless, be produced. When the flowers are evidently arranged to favor self-fertilization, and prevent cross- fertilization, they are said to be cleistogamous (Gr. kleistos, closed). But no known species is altogether cleistogamous. 82. Examples of cleistogamy are furnished by one set of flowers of Viola, Oxalis, some Grasses, etc. “Their petals are rudimentary, or quite aborted; their stamens are often reduced in number with anthers of very small size, contain- ing very few pollen grains, which have remarkably thin transparent coats, and generally emit their tubes while still inclosed within the anther-cells; and, lastly, the pistil is THE FLOWER. 65 much reduced in size, with the stigma in some cases hardly at all developed. These flowers do not secrete nectar, or emit any odor; from their smail size, as well as from the corolla being rudimentary, they are singularly inconspic- uous; consequently insects do not visit them, nor could they find an entrance if they did. Such flowers are, there- fore, self-fertilized, yet they produce an abundance of seed. In several cases the young cap- sules bury themselves beneath the ground, and the seeds are there ma- tured.”—(Darwin.) 83. After fertilization an embryo is developed in the embryo-sac; the ovary enlarges, and the ovules or seeds grow to the normal size. The embryo is the initial plantlet (Fig. 149, 7), and consists of an axis, called the caulicle (Lat. caulis, stem); one , end of which, in germination, grows downwards, and is called the radi- cle; the other end grows upwards, and is terminated by a bud, which is called the plumule; and of seed-leaves, called cotyledons (Gr. kotula, cup). In case of the Grasses, Sedges, Lilies, .Flags, etc., there is a single cotyledon to each embryo, and the group of plants to which they belong is said to be monocotyledonous (Fig. 150). In case of the ‘Pea, Bean, Buttercup, Rose, Ash, Maple, Oak, Chestnut, ete., there are two cotyledons to each embryo, and the Fig. 149. A dicotyledonous seed (Bean) in different stages of germination: +d, radicle ; 47, plumule ; cof, cotyledons ; 4y, hypocotyledonary portion of stem. 5 66 ORGANOGRAPHY. : group to which they belong is said to be dicotyledonous (Fig. 119.) Most of the cone-bearing plants (Conifere) have polycotyled- 4/4) Onous embryos. The nourishment i M for the plantlet during germina- Hila) tion is stored up wholly (Pea, Bean, Maple), or in part (Corn, Wheat), in the cotyle- dons. The portion, if any, stored within the embryo-sac, but not in the cotyledons (Fig. 150, en), is called endos- perm (Gr. endon, with- in); that,if any, outside 151 the embryo-sac is called the perisperm (Gr. pert, around). 84. The integuments of the seed correspond with those of the ovule, and are called the testa. It often has, to assist the dissemination of the seed, outgrowths, in the shape of a wing, as in the Pine, Trumpet Creeper (Fig. 151) etc., or it may have a tuft of hairs, called coma, as the Milkweed (Fig. 152) and Epilobium ; or a hairy covering, as the Cotton-seeds. The testa in many seeds is crustaceous, in others it becomes berry-like, and the edible pulp causes the seeds to be eaten and disseminated by birds. The seed is * Fig. 150. Section of a monocotyledonous seed (grain of Indian Corn): co#, coty- ledon; ~, radicle; AZ, plumule; ez, endosperm. Fig. 151, Winged seed of Trum- pet Creeper (Tecoma radicans). Vig. 152, Comose seed of Milkweed (Asclepias Cornuti). THE FRUIT. 67 sometimes more or less covered by an outgrowth called the aril, as in the Nutmeg (where it is called Mace), the Burning-bush, the Climbing Bitter- Sweet, ete. , 85. The torus is the name given to the end of the axis which supports the floral organs (Fig. 109). It is generally somewhat enlarged and rounded. Jt may be much elongated, as in the Magnolia (Fig. 153); or very much broad- ened, as in the Flowering Raspberry (Rubus). In the Strawberry it is broadened and elon- gated (Fig. 154). Exactly the reverse of this, namely, deeply concave, is exemplified by the Rose (Fig. 155). In the figures (Figs. 163, 164) the receptacle is hollowed out and almost completely closed at the top. In some plants of the Pink family an internode is developed between the calyx and corolla, called the stipe. The elongation may continue between the carpels, as in the Geraniwm and in the Um- bellifere. In Nelumbium it is inversely conical with isolated immersed carpels. A disk is a development of the recep- tacle under or around the pistil. 86. The Fruit.—The Fruit may consist simply of the ripened ovary, with the enclosed seeds, as the Buttercup, Bean, Wheat, etc., or it may consist of the ovary and seeds together with the adnate parts. The Apple, for instance, con- sists of the ovary with the adher- ent calyx-tube (Fig. 156); the Fig. 153. Elongated torus of Tulip-tree (Ziriodendron Tulipifera). Fig. 154 Falarged torus of Strawberry. Fig. 155. Depressed torus of Rose. 68 ORGANOGRAPHY. Strawberry consists very largely of the enlarged and juicy torus. If the fruit is composed . of asingle pistil, either simple or compound, it is called a simple fruit. Those are called aggre- gate fruits which consist of a mass of carpels all belonging to one flower; and multiple fruits are formed by the union of pistils of several flowers. 87. Simple fruits are either dry, as the Bean-pod; or fleshy,as the Plum. Some of the dry fruits spontaneously open at maturity, and are called dehiscent (Lat. dehiscere, to gape), as the Columbine, Larkspur, Shepherd’s-Purse, etc. Others do not open, and are called indehiscent, as the winged fruit of the Maple, seeds of the Thistle, ete. Dehiscent fruits are the Follicle, Legume, Capsule, Silique, and Silicle. Indehiscent fruits are the Samara, Achenium, Utricle, Caryopsis, and Nut. 88. The follicle (Fig, 157) is formed of a supl pistil,. and dehiscent by the ventral suture, that is, the line corresponding to the united edges of the carpellary leaf (Peony). A legume (Fig. 158) is like the above, except that it opens not only at the ven- tral, but also at the dorsal suture, or line corresponding to the midrib of the carpel- lary leaf (Pea-pod). A capsule is the de- hiscent fruit of any compound pistil (Purs- lane). A modification of this is called Fig. 156, Section of an Apple: s, seeds; ca, calyx; ce, carpel; aw, wall of ovary. Fig. 157. Follicle of Columbine, Tig. 158, Legume of the Pea, THE FRUIT. 69 the silique (Fig. 159), or two-valved fruit of the family Crucifere, where the pod has two parietal placente; and often a false partition from which the valves sepa- rate (Mustard). A silicle (Fig. 160) is a short silique (Shepherd’s-Purse). 89. The samara (Fig. 161) is a winged, one-seeded, indehiscent fruit (Ash, Elm, Maple). The achenium, or akene (Fig. 136, ach), is a seed-like fruit, dry, naked, and indehiscent (Anemone, Composite). The utricle is like the akene, but with a thin and bladdery loose covering (Goosefoot). The caryopsis (Fig. 1, 7) is the grain; it completely fills the thin-walled cell, and is consolidated with it (Wheat, Indian Corn). A nut is like an akene, but larger, and often enclosed or surrounded by a kind of involucre (Fig. 162), called a cupule (Acorn, Hazelnut, Hickory). go. The drupe is a fruit, the outer part of which be- comes fleshy, called the sarcocarp (Gr. sarz, flesh; karpos, fruit); and the inner, stony, called the putamen (Cherry, Peach). The pome 4 (Fig. 156) is a fruit with several carpels of parch- ment-like or stony text- ure, covered by flesh (Apple, Pear, Quince). The pepo is the fleshy gourd-fruit, surrounded with a firm rind (Squash, Cucumber, Melon). The berry is a fruit which is fleshy throughout (Tomato, Grape, Currant). Fig. 159. A Silique. Fig. 160. A Silicle. Fig. 161. A Samara of Maple. Fig. 162. Acorn, with cupule, of Shingle Oak (Quercus imbricaria), 7 70 ORGANOGRAPHY. gi. Examples of aggregate fruits, or those in which many carpels belonging to one flower are crowded in a mass, are furnished by the Raspberry, Blackberry, Mag- nolia, etc. Examples of mul- tiple fruits, or those result- ing from the union of several flowers, are furnished by the Pine-Apple, Mulberry, Fig (Figs. 163, 164), Pine, etc. The cone (Fig. 165) is a special kind of multiple fruit. The name is improperly given to the Hop, where the large bracts represent the scales. The cone of the Pine consists of crowded scales, on the upper surface of which the naked seeds are borne. The various fornis assumed by fruits, l:ave, in many cases, evident reference to the dispersion of seeds. 92. The wing of the fruit of the Elm, Maple, Ash, Hop-tree, Birch, Pine, etc., enables the seed to be scattered great distances by the wind. The wing-like, floriferous bract of the Basswood ren- ders the fruit more buoyant and trans- portable by the wind. The pappus (Fig. 87), or persistent calyx of the Thistle, Dandelion, and other Compo- site, often fiuely dissected and downy, causes the seeds to be transported for miles. The Beggar-ticks (Bidens, Fig. 166), Tickseed (Coreopsis), and Burdock, have barbs or hooks, which, 166 Figs. 163, 164. A Fig: 163. Natural size; 164. A portion slightly magnified. Fig. 165. Cone of Hemlock, Fig. 166, Achenium, with barbed pappus, of Bidens Srondosa, THE FRUIT. 71 adhering to the coats of animals or plumage of birds, often effect a wide dissemination of seeds (Tig. 166). The seeds of fleshy fruits, eaten by birds, are generally uninjured by the process of digestion, and are carried sometimes to great distances from the place of growth. Of the multitude of nuts transported by the rodents to their habitations, some woula escape injury, and might give rise to trees at con- siderable distance from the place of their production. 93- In Witch-Hazel the seeds are scattered by the burst- ing elastically of the pod; so also the Touch-me-not. The seeds, together with the pulp, are ejected with force from the Squirting Cucumber (Eebalium). These, though but moderately efficient contrivances, are evidently designed for the dispersal of seeds. Many seed-coats are so firm as to resist for a long time the action of water, and may, therefore, germinate after being transported great distances by river and ocean currents. Seeds may lie dormant for a long-time, and then finally germinate when favorable con- ditions obtain. The spores of Fungi, or Moulds, Puffballs, etc., are produced in countless thousands, and are readily transportable by even gentle winds. It is estimated that an Elm-tree produces upwards of half a million, and a single Tobacco plant forty thousand seeds, numbers which are small in comparison with those of the spores of many cryptogamous plants. This great fecundity is an important factor in effecting the dissemination of seeds, PART II. HISTOLOGY AND PHYSIOLOGY. THE CELL. 94. If a thin, transverse section of a stem or leaf be examined under the microscope, it will be found to consist of a multitude of globular or more or less elongated and flattened bodies, called cells (Fig. 167). These vary in shape in different plants, or even in different parts of the same plant. They may be globular, as in many unicel- lular plants, pollen grains, ete. (Fig. 168); they are pyriform, or pear-shaped, in case of some swarm spores (Fig. 169); they are many-sided, or elongated, in tissue of ordinary plants; they may take Se tas 168 169 170 on a very irregular shape, as stellate (Lat. stella, star), in the tissue of the Rush (Fig. 170); or ramose (Lat. ramus, Fig. 167. Section of stem of Clesatis. Fig. 168, Pollen grain of Morning-Glory. Fig. 169. Swarm spores. Tig. 170. Stellate cells from the stem of Rush ( Hwncus), (72) THE CELL. 73 branch), as in common mould (Fig. 171). The variation is as striking in re- gard tosize; the cells of Bacterium termo, the common fungus of putrefaction, are about .00009 inch long and .00005 inch broad; the Yeast- plant cells are about .0003 inch in diam- eter; the average size of cells of ordinary plants is .005 to .0005 inch; many cells, as of bast, plant- hairs, ete., are not microscopic as those mentioned above, but attain a length of several inches. 95- A cell consists of four parts, namely: (1) the cell- wall (Fig. 172, w), or cell-membrane, a covering enclosing the cell-contents, which are (2) the protoplasm (Gr. pro- tos, first or primitive; plasma, form), a transparent, semi- fluid substance (Fig. 172, pr), con- taining (3) the nucleus, a spher- ical or oval body, denser than the protoplasm (Fig. 172, n), and (4) the cell-sap, a watery fluid occu- pying cavities, called vacuoles (Fig. 172, v). Of these four parts the protoplasm is the only one essential to the growing cell; the other parts may be wanting; swarm spores have no cell-wall ; Fig. 171. Common Mould (partially diagrammatic). Fig. 172. A cell showing the four parts : w, cell-wall ; 7, protoplasm; 7, nucleus; #/, nucleolus ; v, vacuoles. 74 HISTOLOGY AND PHYSIOLOGY. the nucleus has not been detected in the cells of all the lower plants, though never absent in the higher; in very young tissue the cell-sap is not differentiated. From the protoplasm the other parts are secreted or formed; and while the protoplasm remains, the cell continues to live. With age, the cell-wall often thickens, as in woody tissue, and the protoplasm disappears, immediately after which growth ceases. 96. The cell-wall, which is very thin in young cells, often increases considerably in thickness. This thickness is seldom, if ever, uniform throughout the whole wall, and there results, therefore, a variety in its sculpturing. The direction of the thickening may be centrifugal, or out- wards ; or it may be centripetal, or inwards. The first is illustrated by the projections, ridges, etc., on isolated or exposed cells, as in many spores, pollen grains, ete. (Fig. 168). The centripetal thickening is seen in ordinary woody tissue, whose elongated cells are compacted together. The portion thickened may be in the form of rings: (Fig. 178, an), when the thickening is said to be annular (Lat. annulus, ring). The thickened band may be spiral (Fig. 173, sp), and either closely or loosely wound. When the tissue is rudely torn asunder, these spiral bands often uncoil, the thin portion of the wall giving way. The spiral thickening is the most common. The reticulate wall has thickenings so as to present a net-work (Fig. 173, ret), In the scalariform (Lat. scalaria, flight of stairs, or ladder) the thickening is at the longitudinal angles of the cells, and extends across, so as to give approximately the appearance of rounds of a ladder (Fig. 178, sca). 97- When the thickening of the cell-wall is intercepted at numerous isolated spots, it becomes pitted (Fig. 173, THE CELL. 75 Ry. . = ay merreaaee sen iri POR Cee @ RSET 17) Z SSAA 2 : LAB SARI OIZL © jeadiR Z ©) so? Zz | rod Ss oo opal IZ oe okeZre\Z OREASLIK| : oe ANC Po Ce pee Ee a, bor. Sea.” ‘ret. an. Sp SP. Par. pit). These pits or channels may be simple or branched (Fig. 180), and in cross-section appear oval, round, etc. ; or they may be elongated fissures. The woody tissue of the Pine family is characterized by bordered pits (Figs. 174-178), where each pit is surrounded, when viewed from without, with a ring (Figs. 173, bor, and 174) ; this result is brought about thus: a cir- : cular portion of the wall remains thin (Fig. 175), and around this a wall arises and grows inwards (Fig. 176), it wy «175 «76178 Fig. 173. Diagrammatic section through ducts and cells, showing various modes of thickening: P, pith; xy, wood; C, cambium; PA, bast; Cx, cortex ; Zar, par- enchyma; Aros, prosenchyma; s7e, sieve tubes; zt, pitted; bor, bordered pits ; sca, scalariform; vet, reticulated; av, annular; sf, spiral. Figs. 174-178. Bor- dered pits, and their development. 76 HISTOLOGY AND PHYSIOLOGY. forming a low dome (Figs. 176, 177); the overarching wall does not meet in the middle; and this opening furnishes the inner ring, and the bottom of the pit the outer (Fig. 177). Similar growth takes place in corresponding sides of the wall, and the thin partition soon breaks away (Fig. 178), allowing free communication between the cells. Another method of thickening gives "rise to tissue, called colenchyma; here the corners of the cell alone become thickened (Fig. 179). 98. In cell-walls considerably thickened, a differentiation into numerous concentric lay- ers is plainly manifest under the microscope (Fig. 180). This is called stratification, and it is due to the fact that alternate layers contain different amounts of water of organization. The dark layers contain less, and the light layers contain more, water. From a study of the stratifi- cation in starch grains, Nageli was led to the conclusion that the molecules of the cell-wall are aggregated into small particles in the form of crys- tals (each of which he called a mi- cella), each surrounded by a layer of water. With larger amounts of water these particles, or micelle, are pushed ways further apart, and the layer appears light under the microscope. With a ‘ decrease of the amount of water the 180 Fig. 179. Collenchyma, Fig. 180, Hardened cells of the Pear, in which stratifi- cation is shown, THE CELL. 77 particles approach each other, making a dense layer, and appearing dark under the microscope. Sometimes a system of layers at right angles to the layers of stratification is evident, due likewise to varying amounts of water con- tained. This is called striation. Owing to chemical changes a cell-wall may actually become separated into two or more layers or shells, as in pollen grains, spores, etc.; but this has no necessary connection with stratification or striation. 99. The cell-wall is composed of cellulose (which con- sists of carbon, hydrogen, and oxygen, and whose formula is Cy Hy» Oy), water of organization, and ash constituents. The ash or mineral constituents constitute often less than one per cent. of the whole weight of the plant. Three to five per cent. may be considered the average, though it may run as high as twenty or thirty per cent. Potassium, calcium, magnesium, iron, phosphorous, sulphur, sodium (traces of manganese), silicon, and chlorine exist in the ash. In addition to. these, bromine and iodine are found in the tissue of marine plants. The chemical changes, or metamorphoses, which the cell-wall often undergoes are (1) conversion into mucilage; (2) conversion into cork; and (8) conversion into wood, or lignification (Lat. lignum, or, $c. re + ‘ an. 5p. SP Par. ascend from the lowest to the highest, we find a gradual modification of the tissue for special purposes. The outer cells form a boundary tissue, and, together with their ap- pendages, constitute the epidermal system. This in- cludes the epidermis, trichomes, and stomates. Certain other cells, or rows of cells, become modified into tubes or ducts, and form the string-like masses, or form fibers in the stems of the higher plants. These are the fibro-vascular bun- dles. They contain a woody portion (aylem), bast por- tion (phloém), and cambiwm; from the last, the first two are formed. All the other’ tissue, unmodified, or slightly modified, is designated by the term fundamental tissue. Fig. 209. Diagrammatic longitudinal section through tracheary tissue; P, pith; xy, wood; C, cambium; Ph, bast; Cr, cortex; far, parenchyma; fros, prosen- chyma< sze, sieve-tubes ; Az, pitted; dvr, bordered pits; sca, scalariform; ret, re- ticuiated, az, annular; sf, spiral, TISSUE. 93 118. The epidermis is the external, compact layer o1 cells, rarely containing chlorophyll, destitute of intercel- lular spaces, and with their outer walls more or less thick- ened (Figs. 203, 210). When the walls are much thick- ened, the outer portion becomes cuticularized (impregnated with cutin) and impervious to water. Often the outermost portion becomes separated as a continuous pellicle, and is called the cuticle. A waxy, or resinous matter, often forms on the cuticle, and constitutes the bloom found on some leaves and fruits. When the walls become much thickened, the protoplasm disappears from the cells. But in aquatic plants, and the roots of ordinary plants, there is but slight modification from the other cells. The epidermis at first consists of but one layer of cells, but later may split into two or more lay- ers. The inner layers may resemble the outer ones, as in the Oleander; or they may be thin-walled cells, with watery contents (called aqueous tissue), as in the Begonia. 11g. The outgrowths of the epidermis are called tri- chomes (Gr. thriches, hairs), and may have the form of hairs, scales, bristles, prickles, etc. (Fig. 210). They are at first enlargements, or protrusions, of an epidermal cell. They elongate and may remain one-celled, or become many- celled, and take on an endless variety in shape, as may be seen by examining these structures on many different plants. Those elongated, unicellular hairs on the young roots of plants, called root-hairs, have very thin walls, and absorb the plant food which is dissolved in the water of the soil. Fig. 210. Epidermis and hairs from the ovary of the Squash flower, 94 HISTOLOGY AND PHYSIOLOGY. In Mosses, hairs, called rhizoids (Gr. rhiza, root), perform the function of roots ex- clusively, the latter being absent in these plauts. In many hairs on aerial parts of plants, the ter- minal cell, or cluster of cells, becomes trans- formed into a secreting organ, in which gummy, resinous, or other substances are produced. These are termed glandular hairs (Fig. 210, gl). Related to these are the hairs of some Thistles, with elongated lashes. The leaves of the Sundew (Drosera) have stalked, sensitive glands, for the capture of insects upon which these plants partially feed. 120. The stomates (Gr. stoma, mouth) are minute ori- fices (Figs. 211, 212) in the epidermis, surrounded by two chlorophyll-bearing cells, called guard-cells (Fig. 211, 9). Immediately under each stomate is an air cavity (Fig. 212, a). Stomates are never present in roots,:seldom in sub- merged or underground stems; but exceedingly numerous on aerial stems and leaves. They are also met with at times on sepals, petals, and carpels of flowers. As a rule, they are more numerous on the lower than on the upper side of the leaf. On the upper Fig. 211. Epidermis of Potato leaf, showing stomates (s?) and guard-cells (g). Fig. 212. Section through the epidermis and stomate (s¢) of Potato leaf: a, air cavity. TISSUE. 95 side of the leaf of Anemone nemorosa, for example, there are none; on the lower side there are 42,215 to the square inch; on the leaves of Indian Corn there are on every square inch on the upper side 60,630, and on the lower side 101,910 stomates; on the Sycamore leaf there are none on the upper side, but on the lower side 179,310 to the square inch. In the leaf of the common Sunflower there are in each square inch: above, 112,875 ; below, 209,625. Through the stomates, or breathing pores, an interchange of gases takes place. 121. The fibro-vascular bundles are composed of tracheary tissuc, sieve-tubes, and parenchyma. They may be easily separated from the other tissue in the petioles of the Plantain, in the stems of Indian Corn, ete. When examined in section, they are seen to consist of’ tio parts, namely, wood, called xylem; and bast, called phloem (Fig. 213). When cambium (delicate cells, rich in protoplasm, capable of division) is present between them, the bundle is said to be open (Fig. 214, a diagram) ; if it is absent, it is said to be a closed bundle (Fig. 215, a dia- gram). Open bundles continue to increase in size, new layers of wood and new layers of bast being formed from the cambium. The bundles, which are isolated when /” the plantlet is very young, increase oa 215 Fig. 213. Transverse section of a fibro-vascular bundle; P2, phloém; Xy, xylem; C,cambium, Figs. 214, 215, Diagrams illustrating open (erg) and closed (275) bun- dles, 96 HISTOLOGY AND PITYSIOLOGY. in size, fuse laterally into a continuous mass, the cambium in each joining with that of the adjacent bundle, thus form- ing a cambium zone, or layer, which annually produces a ring of wood, as in forest trees. (See Angiosperme, Part III). Closed bundles do not increase in size, and plants having such (as the Asparagus, etc.) do not form an annual ring of growth. 122. The fundamental tissue includes all except the epidermal] tissue and the fibro-vascular bundles. It con- sists mainly of parenchyma of various forms, in contact with or near the epi- dermis. Collenchyma is sometimes present. - This is replaced by sclerenchyma in parts requiring greater firm- 3 ness than that given by the former. The term hypoderm (Gr. ‘ hypo, under; derma, skin) has been used to designate those differentiated por- tions lying immediately beneath the epidermis (Fig. 202, hy). Uaticiferous vessels may also occur in the funda- mental tissue. To this tissue belong the medullary rays in woody plants. Within the zone of the hypoderm, or immediately below the epidermis, layers of cork may be developed (Fig. 216, C’). The cells are generally four- sided in section, filled with air, have thin walls, impermeable to water. The generating tissue (Fig. 216, ph) is called cork-cambium, or phellogen (Gr. phellos, cork; genein, to be produced). When a plant is slightly cut or iajured, Fig, 216, A layer of cork-ceils (C) forming the covering of the Potato, TISSUE. 97 the parenchya-cells immediately under the wound become amass of phellogen, and a protecting mass of cork, called wound-cork, is developed. The epidermis may be replaced entirely by a continuous corky layer, called the periderm (Gr. pert, around). Restricted corky growths below sto- mates may push out the epidermis, as in Elder; and thus roundish, or elongated masses of cork, called lenticels, are formed. 123. At the growing ends of stems and leaves (and roots) is found a tissue composed of cells, with delicate walls, filled with protoplasm, capable of division. This is called primary meristem (Gr. meros, part; temnein, to cut off ,, and from it the various % tissues are developed. As growth proceeds, = portions of the primary meristem. become = transformed into permanent tissue, which is mz incapable of division. The terminal portion ee of an organ consisting of primary meristem, 217 218 and having permanent apical growth, is called the punctum vegetationis, or growing point. As it often projects in a conical elongation it is sometimes called the vegetative cone. The punctum vegetationis may con- sist of a single cell, called the apical cell (Figs. 217, 218, ap), or it may be composed of a multitude of cells (Fig. 219). Many of the Alge grow from an apical cell. This -elongates and divides, the upper portion continuing as the apical cell, which, in turn, elongates, and divides as before ; and so on. The other portion, appearing like a piece or disc cut off from the apical cell, is cailed a segment. The segments may remain undivided (Fig. 217). They may Figs. 217, 218. Diagrams showing growth from an apical cell; segments (/, JZ, Wl, [V) divided (278) and undivided (277). 7 98 HISTOLOGY AND PHYSIOLOGY. divide into two cells, which, in turn, divide, and so on in- definitely (Fig. 218). 124. In the higher plants, the punctum vegetationis has no apical cell. Here the pri- mary meristem consists of cells which are very small and numerous. The outer- most layer of cells is continu- ous, with the epidermis of the older portion further back. In fact, it produces it. Hence it is called the primordial epidermis (Fig. 219, D), or dermatogen (Gr. derma, skin; genein, to be produced). Beneath the dermatogen are generally found several continuous layers out of which the cortex originates. These are called the primordial cor- tex (Fig. 219, Per), or periblem (Gr. periblema, cloak). The nucleus of tissue, enclosed by the periblem, and out of which the fibro-vascular bundles and pith are produced (Fig. 219, Pler), is called the plerome (Gr. pleroma, a fill- ing up). A short distance back from the apex of the punctum vegetationis the leaves (and buds) take their origin as exogenous structures, that is, from the external cell-layer, or dermatogen. 125. The root, like the stem, is furnished with a punctum vege- 220 Fig. 219. The growing point, or punctum vegetationis, in longitudinal section; D, dermatogen; Per, periblem; Pler, plerome. Fig. 220, Diagram of longi- tudinal section through the root-tip, showing the apical cells (4) and the root-cap (R.c). TISSUE. 99 tationis, either with or without an apical cell. The Fern root furnishes an example of the first (Fig. 220), and the root of any of the higher plants an example of the second (Fig. 221). While the tender punctum vegetationis of the stem is protected by the overarching of the young leaves, that of the root is furnished with a peculiar shield- ing structure, called Pler. D the root-cap (Fig. ° Pry 221, R.c). This con- NY) \ ) Ud ; sists of a mass of cells 4 HH developed from the \Y aH dermatogen. The lat- OH ter divides into two Ane layers, the innermost A An (K s continuing as the der- Mies U, matogen, to be subse- quently divided in the same manner. The outermost multiplies > its cells copiously, and ; al, constitutes the root-cap. The outer cells of this are, of course, continually abraded as the rootlets push their way through the soil, but as constantly replenished from behind. The root is further distinguished from the stem in having its branches (side roots) developed as endogenous struc- tures, that is, from cells a distance below the epidermis; having no stomates, no joints, no chlorophyll, and no leaves, Fig. 221. Diagram of longitudinal section through the root-tip, showing the initial cells (2.2.), and the root-cap (&.c), 100 HiSTOLOGY AND PHYSIOLOGY. WATER. 126. All living vegetable tissue is abundantly supplied with water. In aquatic plants it may constitute as much as ninety-five per cent. of the whole weight. In the terres- trial plants it generally averages about seventy-five per cent. In consequence of this quantity of water the cells are rendered turgid, without which growth would be im- possible. If green _ plants be dried in (X/3 the air at ordinary \) temperatures, they lose only a por- tion of their water. ' Thus Red Clover contains seventy- nine per cent. of water, and when air-dry (hay) it contains seventeen per cent. Fresh Pine-wood contains forty per cent. of water, and the same dry contains twenty per cent. The first quantity in each case may be called the free water of vegetation. The second represents the water of organization. The root- lets and root-hairs which penetrate the soil, growing between the more or less minute soil-particles, where water is con- tained (Fig. 222), are the organs of absorption. 127. The tendency of the water in plants to assume a state of equilibrium is disturbed by three causes; namely, Fig. 222, Diagram representing a root, with root-hairs penetrating the soil; s, soil-particles ; 4, root-hairs ; a, air, WATER, 101 (1) chemical processes within the cells; (2) the imbibition of water by the protoplasm and cell-walls; and (3) the evaporation of a portion of the water. All these are in almost constant operation; and, therefore, there is a per- petual movement of water in the growing plant. The chemical processes include the actual consumption of water by breaking the molecule up into oxygen and bydro- gen, the formation of substances which are more soluble than those from which they were formed, and the formation of others less soluble than the substances from which they were formed. The protoplasm has imbibing power in a marked degree. It imbibes more water than it can retain, the surplus being separated in drops, the so-called vacuoles. The protoplasm of rapidly growing tissue is more watery than that in a dormant state, as in seeds. The cells are kept turgid, and succulent parts made rigid. 128. The evaporation (called also exhalation and transpiration) of water from the surface of plants is a more potent agency disturbing the equilibrium than the two previously mentioned. No evaporation, however, can take place when the air is saturated with moisture. The further below the point of saturation the amount of moist- ure falls, the greater is the amount of evaporation. The epidermis offers considerable hindrance to the process; and the thicker and less impermeable they are, the less the amount of water which escapes. In such case the escape is mainly through the stomates, which may be considered special organs of exhalation (and breathing). They are placed over intercellular spaces (Fig. 212), and these are connected with intercellular passages, which, af course, are filled with moist air and gases. Stomates open more widely the greater the amount of light, and the greater 102 HISTOLOGY AND PHYSIOLOGY. the amount of moisture on the epidermis. Another partial hindrance to more rapid evaporation lies in the fact that the water contains ‘many substances in solution, which, as is known, evaporates more slowly than pure water. 129. The rate of evaporation is very slow. It was long ago found that the amount of water evaporated from a vine in twelve hours of daylight was equal to a film only .005 inch thick, with an extent equalling the evaporating sur- face; the amount from a Cabbage in the same time equalled a film .012 inch thick; from an Apple-tree .01 inch. The evaporation from most leaves is estimated to be about one- third that from equal areas of water. A close-topped Oak-tree, twenty feet high, having about 700,000 leaves, evaporated (according to calculation) 246,630 pounds of water during the growing season of five and a half months. This amounted to a layer of water 1.81 inches deep over the whole evaporating surface. Considered with reference to the area of ground covered by the tree-top, it was found that the evaporation from the tree was cight times as great as the annual amount of water which fell beneath it. The evaporation would be much less in dense forests, yet even there it is sufficient to deprive the ground of its moisture in a short time in a dry, hot season. 130. To supply the loss by evaporation there must be a movement of water through the roots, stems, and branches to the leaves. This is demonstrated by cutting off a leafy shoot when evaporation is going on rapidly; the leaves wither quickly from loss of water, but if the cut end be placed in water, the latter passes up through the stem and supplies the loss from the leaves, which then retain their normal condition. If in this experiment a colored watery solution be used, it will be evident that some kinds WATER. 103 of tissue conduct move rapidly than others. In ordinary plants the elongated wood-cells convey the water mainly. The rapidity of the ascent is dependent on the rate of evaporation; but in general it may be considered to vary between the limits of five and fifty inches per hour. The so-called root pressure may be shown by cutting off a vigorously growing plant at the ground, and attaching a glass tube in which the water will rise to a considerable height (36 inches in Vitis, 84 inches in Betula). This is supposed to be due to a purely physical (endosmotic) force. 131. The water absorbed from the soil by the rootlets holds, in solution, inorganic food- materials for the plant. Even pure water is a solvent for many kinds of rocks and min- erals, which, in a more or less finely divided state, constitute soil. In consequence of this fine state of division, the surface exposed to the action of water, and consequently the amount of material dissolved is enormously increased. Water charged with carbonic diox- ide (called carbonated water), as the soil water invariably is, has its solvent power greatly increased. When such water is heated, or so exposed as to louse its carbonic dioxide, it is forced to precipitate the minerals contained, as illustrated by the lime-coating in boilers and in tea- kettles. The solvent power is still greater when the water contains alkalis—ammonia, potash, and soda: in fact, up to a certain point, “its solvent power increases with the amount and number of matters dissolved.” Besides, the root-hairs themselves (Fig. 223) attack and dissolve the Fig. 223. A root-hair highly magnified, showing its attachment to thesoil-particles (s). 104 HISTOLOGY AND PHYSIOLOGY. soil-particles. If a polished granite, or marble slab, be placed under the soil, exposed to the action of the rootlets, and then examined at the end of the growing season, it will be found to be sensibly roughened and dissolved wherever the rootlets came in contact with it. FOOD-ELEMENTS. 132. The food-elements, which plants consume, may be determined in two ways: (1) by chemical analysis of vegetable tissue; or (2) by causing plants to grow in pure water, to which are added the compounds containing the elements that will nourish them. They have been found to be carbon, hydrogen, oxygen, nitrogen, sulphur, iron, and potassium. If all these are present, the plant will grow; if any one or more are absent, the plant will die of starvation. Besides these seven elements, plants appropriate phosphorous, calcium, sodium, magne- sium, chlorine, and silica. These six are of secondary importance, for without them the plant may grow. In marine plants, iodine and bromine are always present. In special cases are found also at times small quantities of aluminum, copper, zinc, lithium, manganese, nickel, cobalt, strontium, and barium. Calcic fluoride is. contained in the bones of animals; and, as their food is furnished wholly by plants, the presence of fluorine in the latter is inferred. 133. Oxygen may enter the plant in a free or uncom- bined state. All the other elements are absorbed in the condition of compounds, namely, water, carbonic dioxide, and the nitrates, sulphates, carbonates, phosphates, silicates, and chlorides of ammonia, potash, lime, iron, soda, and magnesia, Carbon constitutes usually about one-half of the entire dried substance of the plant. Yet this large FOOD-ELEMENTS. 105 quantity is derived mainly from the decomposition of car- bonie dioxide (CO,), taken into the leaves through the stomates from the surrounding air, of which it constitutes on an average only four hundredths of one per cent. Hy- drogen is present in much smaller quantity than car- bon. It is probably derived mainly from the decomposition of water (H,O). Oxygen forms the largest proportion, after carbon, of the weight of the dried vegetable substance. It is introduced into the plant in excessive quantities, in the form of water, carbonic dioxide, and oxygen-salts, and also absorbed directly from the atmospheric oxygen. The small quantity of nitrogen is obtained from the compounds of ammonia (NH;) and nitric acid. Sulphur is furnished by the salts of sulphuric acid. 134. The elements, carbon, hydrogen, oxygen, nitrogen, | and sulphur, compose the greater (combustible) part of the. substance of plants. They are constituents of cellulose, and the albuminoids which form protoplasm. “They mainly form the organized and organizable part of the plant, and of every individual cell. Their importance, therefore, lies in the fact that they furnish the chief mate- rials for the construction of the plant.” Iron is indispen- sable for the production of the chlorophyll, though extra- ordinarily small quantities suffice. If large quantities of solutions of iron become distributed in the tissues of plants, the cells quickly die. The importance of this food-element is great, since without chlorophyll no assimilation takes place. It has also been demonstrated that the presence of potassium is necessary to the assimilating activity of chlo- rophyll. If it is absent, the plants do not increase in weight, but behave as if absorbing only pure water. 106 HISTOLOGY AND PHYSIOLOGY. ASSIMILATION AND METASTASIS. 135. The change into organic matter of the mineral or inorganic substances taken into the plant as food is called assimilation. The process takes place only in sunlight, and then only in cells containing chlorophyll. It is, how- ever, as yet but imperfectly understood. It appears that water and carbonic dioxide become decomposed in the chlorophyll-mass, and their elements recombined to form carbo-hydrates. In most plants starch is the first visible product of assimilation in the chlorophyll grains. Some- times no‘starch is formed, but instead, oily or sugary matters, which are chemically similar. The oxygen in starch is less than in water and carbonic dioxide, therefore ‘assimilation is a deoxidizing process, large quantities of free oxygen being given off by the plant. Plants, destitute of chlorophyll (as Indian-pipe, Beech-drops, Fungi, etc.), are compelled to live on the assimilated products of other plants, as in case of Parasites (Gr. para, beside; sitein, to feed), or on the juices or products of decaying organic matter, as in case of Saprophytes (Gr. sapros, rotten ; phy- ton, plant). 136. Of the plants which obtain their food partly or wholly from some other source than assimilation, there is, besides the parasites and saprophytes, a group called insectivorous plants. A common example is the Sun- dew (Drosera), which grows in bogs and wet places. The radical Jeaves are furnished with stalked glands, whose glistening secretion imprisons flies which alight thereon. The flies soon die, and are then digested by the acidulous secretion, which is at such time more copiously poured forth. The nutritive portion is absorbed into the plant, ASSIMILATION AND METASTASIS. 107 and thus furnishes a por- tion of its (nitrogenous) food. Venus’s Fly-trap, the e lobes of whose leaves close and capture insects when the latter touch the slender hairs on the upper side (Fig. 223a), is likewise capa- ble of digesting animal food. The numerous sessile glands provide the digestive secretion, and also absorb into the plant the digested portions of the insects. Glands, whose viscid secretion is capable of digesting nitrogenous material, are also found on the leaves of the Butterwort (Pinguicula), which grows on wet rocks and damp soils. The curious little bladders (Fig. 224) of the Bladderwort (Utricularia) capture small water-animals. In the pitchers (Fig. 225) of the Sarracenia and Nepenthes, insects fall and drown; these animals, by their decay, probably furnish fond to be ff absorbed by the plants. 137. The immediate products of assimilation undergo further (though but slightly understood) chemical changes to form the various substances found in vegetable tissue. All these changes, subsequent to assimilation, are collectively termed metastasis (Gr. meta, over; istamai, to place). Metastasis is a process of oxidation ; Fig. 223a. Leaves of Venus’s Fly-trap (Dionza). Fig. 224. Bladder from the stem of the Bladderwort (U¢ricu/arvia), slightly magnified. Fig. 225. A leaf, having the form of a pitcher or cup, of Sarracenia. 108 HISTOLOGY AND PHYSIOLOGY. it, therefore, consumes oxygen instead of liberating it, as in assimilation. Instead of increasing the weight of the plant, as is the case in assimilation, it decreases it; it takes place in all cells, and in darkness as well as in sunlight. At the expense of the elaborated materials,—called formative material,—growth of tissue, that is, the multiplication of cells, takes place. This may occur at once, or a portion of the formative materials may be stored up for subsequent use. hus, in case of the Potato-plant, starch, which is formed in the chlorophyll grains in sunlight, becomes dissolved when darkness sets in, and is transported through the parenchyma and thin-walled cells of the phloém to the reservoir of reserve material. The tuber, bulb, rhizome, stem, seeds, and spores hold in store varying amounts of reserve material. 138. This reserve material furnishes the elaborated food for the beginning of the subsequent period of growth; thus, from that stored up in stems and roots, the buds develop in. the spring; from that in the bulb, a cluster of flowers may form; from that in the tuber, the “eyes” (buds) develop into branches; from that in the seed, the embryo unfolds into a self-supporting plantlet. The reser- voirs are emptied gradually as the growth of the new organs progresses. When they are entirely empty, growth ceases, unless the conditions of assimilation (presence of chlorophyll and sunlight) render the formation of new organic material possible. The direction of the transport of assimilated materials is from the assimilating organs directly to the growing parts, or to the reservoir of reserve materials, thence to the growing parts. The movement is mainly one of diffusion. “The pressure caused by the tension aud turgescence of the tissues has, in addition, a RESPIRATION. 109 tendency to propel the fluids in the direction of least resistance, which is also that in which they are consumed.” RESPIRATION. 139. The respiration of plants consists in the absorp- tion of atmospheric oxygen and the liberation of carbonic dioxide. This cannot be readily detected while assimila- tion is going on, for then much larger quantities of oxygen escape. Nevertheless, respiration is constantly performed, causing oxidation of the assimilated substances and other chemical changes resulting from this. “The loss of assimilated substance caused by respiration would appear purposeless if we had only to do with the accumulation of assimilated products; but these are themselves produced only for the purpose of growth, and of all the changes with life; the whole life of the plant consists in complicated movements of the molecules and atoms; and the forces necessary for these movements are set free by respiration.” In the absence of oxygen, the chemical changes connected with growth, the movements of the protoplasm, and the power of motion of motile and irritable organs cease. The heat generated by oxidation seldom causes a sensible increase in the temperature of the tissue. But in a mass of germinating seeds, or unfolding flowers, or a spadix during anthesis, the elevation of temperature may be observed. The phenomenon of phosphorescence also depends—in a manner not clearly demonstrated—on the respiration of oxygen. 140. The degree of temperature at which assimila- tion and metastasis may take place varies in different plants. Some plants live wholly in very low temperatures, as the Red-snow plant. In Polar watcrs myriads of 110 HISTOLOGY AND PHYSIOLOGY. Diatoms and some of the higher Sea-weeds (Fucacee, Floridee) flourish. Of our ordinary land plants, subjected to different temperatures, the greatest growth of the plumules took place as follows: Pet. 4 A Ree A ew RS 78.8° F. Wiieat «6m 5c e ea Be Bw Sw < 92.7° BF, Jaden (Corie he Sees we ee 92.7° F. Scarlet Bean. . 2 1 ee ee ee ee 92.7° F. In other experiments it was found that the most rapid growth of roots was at the following temperatures: Scarlet: Beans «+. «5 & oe ee eH 78.8° F. POR A cop Sozetlaltsy, Givget te e eetey cae ak 79.9° F. PIAS 4H ee so, he GS ae a ag 81.3° F. WW Hieaib aan tong ek sae A Sa ieee SS oe orc 83.3° F. Tidian (Corn... 22.2 ee es a OS 92.7° F, The following table shows the lowest (minimum), the most favorable (optimum), and the highest (maximum) degree of temperature at which seeds of several plants will germinate: SEEDs. Minimum. | Optimum, | Maximum. Indian Corn... ..- - 48.8° F. | 92.7° F. | 115.2° F. Scarlet Bean. . 2... - 48.8° F. | 92.79 F. | 115.2° BF. Pumpkin. ...... 56,7° F. | 92.7° F. | 115.2° F. Wheat: rw. ie eo Ay ear Alo BF, 83.7° F. | 108.5° F. Barlléy?-<. css ce css 41° BF. 83.7° F. | 99.5° F. Plax vk oes wt as ss 35° F. 81° F, oa Péai.. 2 & Xs we a 43° F, 80° F. Hetip.. 6 «© 4.4 aa a # se ao [882° Ws Watermelon. . ... - eas | 995° FR. Metastasis may take place at lower temperatures than assimilation. In the growth of many plants in spring, at the expense of the reserve material, metastasis takes place RESPIRATION. 111 at quite low temperatures, as many plants begin to grow and develop flowers simultaneously with the disappearance of the snow. 141. Plants may be killed by too high a temperature, as well as by too low a temperature. Those which contain least water can best endure high temperatures; many dry spores and seeds are uninjured at 149° to 177° F., but in water they are generally killed when the temperature exceeds 122° or 131° F. Aquatic plants can seldom endure a prolonged temperature above 104° F.; most terres- trial plants are killed at 122° F. At such temperatures the albuminoids of the protoplasm coagulate, lose their power of imbibing water, and the cells, therefore, lose their turgidity. Similar results follow too great a reduction of temperature. Those tissues containing most water are more quickly killed; seeds when dry endure almost any low degree of temperature, but, when they have become watery and germinated, a reduction to, or a little below, 32° F. generally kills them. Succulent tissues when frozen may sometimes survive by being subjected to a very slow thaw- ing. In this case the water of the melting ice-crystals could be reabsorbed by the protoplasm or other substances which originally yielded it, and no injury done; but in rapid thawing the reabsorption of all the water could not take place. 142. The presence of light is a necessary condition upon which vegetable growth, either directly or indirectly, depends. Assimilation takes place in the chlorophy]l-mass, and this is developed only under the influence of light. The assimilated products may undergo the metastatic changes in darkness as well as light; and those organisms (parasites and saprophytes), whose food is furnished by chlorophyll- 112 HISTOLOGY AND PHYSIOLOGY. bearing plants, may pass their entire existence in dark- ness. The degree and kind of light influences the amount of assimilation. There is here, as in case of temperature, a minimum, optimum, and maximum intensity. If the amount of assimilation in white light be taken as 100, that for each of the isolated rays of the solar spectrum is found on the average to be as follows: Red, 9.5; Orange, 23.5; Yellow, 27.3; Green, 14; Blue, 82; Indigo, 5; Violet, 2.5, The more refrangible rays are less efficacious; from the yellow and orange rays there is a decrease in both directions ; and in the heat and actinic rays, found respect- ively beyond the red and violet, no assimilation whatever takes place. : MOVEMENTS. 143. If all other conditions are made constant, the rapidity of growth of most aerial stems is greater in dark- ness than in light. This is due to the retarding influence of the rays of high refrangibility (blue, indigo, violet, and ultra-violet), When, therefore, the illumination is greater on one side of the stem than on the other, a curvature arises in consequence of the retarding influence of light. Thus, when plants are grown in windows, they curve strongly towards the light. This phenomenon has received the name of heliotropism (Gr. helios, sun; trepein, to turn). It is due to the fact that the growth of the cells on the illuminated side is retarded, while on the opposite side the cells elongate, causing a curvature. Some organs, however, bend away from the light, indicated by the term negative heliotropism (the former being positive heliotropism), the explanation of which is not as yet clear. Thus the tendrils of the Grape-Vine and Virginia MOVEMENTS. 118 Creeper are negatively heliotropic; and they, therefore, turn to walls or trees, to which they attach themselves for support of the plant. 144. The stems of most of the higher plants grow upwards, or from the earth, and the roots grow downwards, or towards the earth; the stems of most Mosses grow upwards, and their rhizoids downwards; the spore-bearing (conidia) filaments or hyphe of some Fungi grow upwards, and the root-like hyphe downwards. To designate these phenomena of growth, the term geotropism (Gr. ge, earth; trepein, to turn) has been used. The organ is positively geotropic if it grows downwards; and nega- tively geotropic if it grows upwards. That geotro- pism is due to the influence of gravitation may be demonstrated by placing germinating seeds on rapidly rotating wheels, If the rotation is vertical, the centrifugal force is substituted for gravitation, and the roots grow away from the centre or hub of the wheel, and the stems grow towards it; if the rotation is horizontal, the cen- trifugal force and gravitation act at right angles, and the roots will grow in a line coinciding with a diagonal, or resultant of the two forces, outwards and downwards, and the stems will grow upwards and inwards. If geotropic organs are placed horizontally, they will curve upwards or downwards, even when considerable resistance is offered. The cells are more elongated upon the convex than upon the concave side; but how gravitation causes this has not as yet been explained. 145. A few plants exhibit spontaneous movements of some of their foliar organs. In Desmodium gyrans, a plant of India, with trifoliate leaves, the small lateral leaflets bend continually upon their slender stalks in such 8 114 HISTOLOGY AND PHYSIOLOGY. a way that their apices describe nearly a circle in from two to five minutes. Less conspicuous sponta- neous movements take place in Clover, Mimosa, Oxalis; but they are generally con- cealed by more marked movements due to other causes. Thin walled cells compose the tissue of the active part of the moving organ. “ The cells are turgid, and the tissues are in a state of tension, when movements occur it appears that the protoplasm in cer- tain layers of cells permits the escape into the intercellular spaces of a portion of the water of the vacuoles; it is, however, quickly absorbed again, and the cells rendered thereby turgid, while the escape of water takes place in contiguous layers, to be quickly absorbed again, and so on regularly around the axis of the contracting organ.” 146. Certain other movements depend upon external stimuli, The leaves of many plants assume a position (Fig. 227) at night (sleep) different from the ordinary or diurnal position (Fig. 226), in con- sequence of seusitiveness to light. Thus the leaves of Clover, Vicia, Lathyrus, and Honey-Locust fold upwards at uight; those of the Locust and Oxalis downwards. The common petiole of Mimosa turns downwards at night; that of Phaseolus becomes erect. The leaflets of Mimosa turn laterally for- wards and upwards in the dark; those of Tephro- sia backwards. The petals of the Tulip, Oxalis, Portulaca, ete., open and close alternately in the Fig. 226, Diurnal position of the leaflets of the Honey-Locust. Fig. 227. Noc- turnal position of the same. MOVEMENTS. 115 morning and evening, or upon a change of weather. The leaves of various species of Oxalis, Mimosa, etc., are sensi- tive to contact and concussion. A violent or repeated concussion, in some cases even gentle contact, causes the parts to assume the position of sleep. The stamens of the Barberry, in contact with the corolla when at rest, curve inwards when lightly touched near the base, bringing the anther in contact with the stigma. The stamens of the Centaurea and other Composite are sensitive to irrita- tion. When at rest, their free filaments, bearing synge- nesious anthers, curve concavely outwards; on contact or concussion, they contract and straighten, lengthening again after some minutes, and resuming their curved form. “This phenomenon occurs only while the style is growing through the anther-tube, and the pollen is being emptied into the tube. The motion of the filaments effected by insects causes the anther-tube to be drawn downwards, and a portion of the pollen thus to escape above it, which is then carried away by insects to other flowers and capitula when the stigmas are already unfolded.’ 147. It often happens that growth takes place more rapidly first on one side of an organ, and then on the other side; and then by the alternating rate of elongation on the two sides,a movement of nutation in one plane will take place. Many leaves furnish a good example; in the bud the greater growth is on the under or outer side of the leaf, the latter bending upwards; but on the opening of the bud the greater growth takes place on the upper side. Floral leaves often exhibit such nutations, as do also many stamens and styles. If the parts of unequal growth, instead of alternating from side to side, pass regularly around the organ, a revolving nutation will be the 116 HISTOLOGY AND PHYSIOLOGY. consequence. This is illustrated in twining plants and tendrils. The former generally rotate to the left; though the Hop, Honeysuckle, and others, rotate to the right. When they touch an upright object they continue their rotation, and thus twine around a support. Tendrils (Fig. 228) grow straight until they have attained about three-fourths of their size. They are then sensitive to contact, and are continually revolving; when they come in contact with any object, a curva- ture takes place, and a number of revo- lutions are performed around the support (Fig. 228, s); whether the coils are few or many, they become attached with con- siderable force; that portion between the point of contact and base also coils in a cork-screw manner (in two directions, Fig. 228, 7 and v, since both ends are attached), and this brings the plant nearer the support. Tendrils which do not find an object to encircle, become abortive and fall off (in the Grape-Vine and Virginia Creeper), or roll up slowly from the apex to the base, and form a spiral (in Cardiospermum), or a helix (in Cucurbita), then dry up and beconie woody. Fig. 228. Tendril of Wild Balsam-apple; 7, 2, 9, the three branches; ten, ten- dril ; s, support; ~, coil to the right; 2, coil to the left; 24 petiole of leaf; /#, stem of a fruit; s¢, branch, , PART IIL. SYSTEMATIC BOTANY. CLASSIFICATION. 148. All individuals which very closely resemble each other in every particular (as regards the stem, leaves, flowers, fruit, etc.}, or are so nearly alike that they may without hesitancy be referred to an immediate common parentage, constitute what botanists calla species. Thus all the Red Clover plants are—unless subjected to some abnormal or peculiar influences—so nearly alike that a minute description, or an exact figure of any one, would be an accurate account or representation of any other indi- vidual; the same may be said of the individual White Oaks, Locusts, Dogwoods, May-Apples, Dandelions, or any other plants; each of these, therefore, is a separate species. That individuals of different species occasionly pass, by a series of immediate forms, into one another cannot be denied. The large majority of species now existing, how- ever, are well marked ; and though closely related to some others, their characters appear constant, and they do not perceptibly tend to vary into each other. 149. The seeds of any species of plants will, when sown, produce individuals exactly, or approximately, like the adult. The same is true for all succeeding generations, so far as is known by actual experiment or observation. It sometimes happens, however, that certain individuals differ (117) 118 SYSTEMATIC BOTANY. slightly, but evidently, from the typical form; the latter may be smooth, and the individuals in question hairy; the difference may be in the size of the plants, or in the color of the flowers, shape of the leaves, or any other minor character. If the descendants of these individuals differ in the same respect from the typical form ; or, in other words, if their characters are constant, they constitute a variety of that species. Thus, one of the wild Buttercups: (Ranunculus abortivus) has smooth, rather large stems; but a form of it (Ranunculus abortivus, var. micranthus) has smaller, hairy stems. The cultivated Snow-ball is a variety of the wild High Cranberry (Viburnum Opulus); the latter has only the outer flowers of the cluster enlarged and conspicuous (neutral); in the former, they are all thus characterized. The amount of variation, within varietal limits, cannot of course be conventionally determined ;_ some botanists may, in particular cases, call species what others designate as merely good varieties. 150. An individual of any species may occasionally show a conspicuous variation from the typical form; as, a Violet without a spur, a Strawberry plant with simple leaves, a regular flower, when the flowers of the plant are labiate; and so on. Such characters are not transmitted to descendants; the latter present the typical form. Individ- uals behaving in this manner are called sports. Exaggera- tions of such tendencies often produce monsirosities. These are sometimes instructive, especially in cases of reversion. Thus in a monstrous flower, the several organs may revert to the form of leaves, of which evidently, therefore, they must be considercd modifications; or a flower-bud may develop into a branch, showing that the flower is homolo- gous with the latter. The influence of cultivation (sub- . CLASSIFICATION. 119 jecting the plant often to conditions abnormal to it) in producing monstrosities, sports, races, and varieties (in the sense understood by gardeners) is very marked. Thus, there are hosts of forms of the Dahlia in cultivation, all derived since 1802 from Dahlia variabilis; the Pansies, from Viola tricolor, are also numerous; “some Melons are no larger than smail Plums, others weigh as much as 66 pounds; one variety has scarlet fruit, another is only one inch in diameter, but three feet long; one variety can scarcely be distinguished externally or internally from Cucumbers ; one Algerian variety suddenly splits up into sectious when ripe.” 15r. The several species of Willows have a marked resemblance to each other: the same may be said of the various Oaks, Oziers, Clovers, Violets, etc. A group of such nearly-related species is designated by the word genus. Thus, there isa genus of Oaks (Quercus), a genus of Roses (Hosa), a genus of Toad-stools (Agaricus), a genus of Rusts (Puecinia), and so on. The genera includ- ing the Bean (Phaseolus), Pea (Pisum), Vetch (Vicia), Lathyrus (Lathyrus), and several others, have a general resemblance in foliage, flowers, fruit, ete.; and they are, therefore, grouped together, and constitute a family, called, in this case, Leguminose. Others, as the Iron- weeds (Vernonia), Thistles (Cirsium), Dandelion (Turaza- eum), Hieracium, Lactuea, ete.—characterized by having the flowers in an involucrate head with syngynesious anthers— torm the family Composite. In like manner, that is, by more or less closely related genera, other families, as Ranunculacee, Crucifere, Labiate, Graminee, ete., are formed. Larger groups, or orders, are formed of families, and still more comprehensive are the so-called classes. 120 SYSTEMATIC BOTANY. The names, Division, Class, Tribe, Cohort, Order, and Family are not always used with exactly the same signifi- cation by different botanists. 152. The system of nomenclature, perfected by Linneus, and used since his time, is binomial; that is, every plant is designated by a double name, the name of the genus followed by the name of the species, both being Latin, or Latinized words. Thus the botanical name of Black Walnut is Juglans nigra, L.; of Sugar-Maple, Acer sac- charinum,Wang.; of Ground Ivy, Nepeta Glechoma, Benth., etc. The specific name is generally an adjective, and, therefore, is not to be capitalized, unless it is a proper adjective, as in Sanguinaria Canadensis ; sometimes it is an old substantive, or the name of a person, in which cases the capital is retained, as in Magnolia Umbrella, Lam.; Phacelia Purshii, Buck. The generic name is a substan- tive, always capitalized, and may be the old classical name, as Platanus, Acer, Nepeta; a name formed from Latin, Greek, or other words, as Trifolium (Lat. tri, three; folium, leaf), Zea (Gr. zao, to live), Datura (Arabic Tatorah) ; or the name of a person, as Claytonia (after John Clayton, an early botanist of Virginia); Linnea (after Linneus, the immortal Swedish botanist, born 1707, died 1778). The abbreviation of the author’s name is also added when botanical names are written. Thus, Z., Wang, Benth., in the names above are for Linnceus, Wangenheim, Bentham, who described and named the several species. 153. Many attempts have been made to classify plants, but until recently the arrangement was very artificial, in as much as undue stress was laid on one, or a few charac- ters, to the exclusion of all others. By this method plants, very much unlike in gencral, were often brought near DIVISIONS. 121 together, or into the same group; and plants closely related were sometimes widely separated—in other words, the classification was far from being natural; it was artificial. By taking into account all the characters of the adult form, and its development, or embryonic changes it passes through to reach that form, an approximation to a natural system of classification can be made, even in the present state of botanical science. Many of the lower plants are as yet very imperfectly understood, and, therefore, not really classifiable. They have been temporarily placed in a separate division, called Protophyta (Gr. protos, first, simple; phyton, plant). DIVISIONS. 154. The Vegetable Kingdom may be grouped into the following Divistons: 1. Protophyta, such as Slime-Moulds, Bacteria, Ycast- plant, ete. 2. Zygosporee (Gr. zugon, yoke), Water-net, Dia- toms, Spirogyra, Moulds, ete. 3- Oosporez (Gr. odn, egg), Peronospora, Fucus, Sargassum, ete. 4. Carposporee (Gr. karpos, fruit), Erysiphe, Lichens, Wheat Rust, Toad-stools, ete. 5. Bryophyta (Gr. bryon, moss), Mosses and Liver- worts. 6. Pteridophyta (Gr. pteron, wing), the Ferns. 7. Phanerogamia (Gr. phainos, visible; gamos, union), ordinary flowering plants, herbs, shrubs, ete. The first four groups are called Thallophyta (Gr. thallos, frond), or plants without distinction of stem and leaves; and the last three groups are called Cormophyta (Gr. 122 SYSTEMATIC BOTANY. kormos, trunk), or plants with differentiation of stem and leaves. It will be noticed that the old groups of Algz and Fungi are abandoned in this classification, though the two are physiologically quite distinct. The terms will be frequently used; Algee, denoting thallopbytes with chloro- phyll (and, therefore, assimilating inorganic matter) ; and Fungi, thallophytes destitute of chlorophyll, and hence parasitic or saprophytic. The first six groups are sometimes called cryptogams (eryptogamia, Gr. kruptos, hidden ; gamos, marriage, or union), or fowerless plants, - and they produce spores (destitute of an embryo); the last group is called phenogams, or flowering plants, and they produce seeds (having an embryo). PROTOPHYTA. 155- The lowest and simplest plants are included in the O group Protophyta. They are often 0 iz 4 Py exceedingly small, and can be seen only IT. @ yw with the high powers of the microscope. 229 230 231 232 ‘The nucleus has not been detected in the cells of all of them, and some are destitue of a cell- wall. The cells are either isolated or but loosely united into families. The usual mode of multiplying is by fis- sion; that is, a cell, after attaining a certain size (Fig. 229), begins to constrict in the middle (Fig. 230), and this continues (Fig. 231) till it is separated into two portions (Fig. 232), each of which is a new cell. A modification of the method of reproduction by fission is exhibited in the so-called budding. On the adult cell (mother-cell) is pro- duced a small cell (daughter-cell) which eventually becomes separated (Fig. 235), Still another mode of reproduction Figs. 229-232. Successive stages in the process of multiplication by Fission. PROTOPHYTA, 123 is presented by some of the members of this group, viz. by the formation of spores (Fig. 233). 156. As representatives of this division (Protophyta), the Myxomycetes, or Slime-Moulds, are the most re- markable. During their growing, or vegetative stage, they consist of a homogeneous mass of colored (but never green) protoplasm, which has received the name of plasmodium. There is no cell-wall; there is a streaming or circulation in the mass of protoplasm, and the latter can, by constant change of form, move slowly around on the damp decaying wood, or vegetable mould, where these plants are often to be met with. In their vegetative state they are so much like the lower animals (Jfonera) that they were, for a long time, considered as belong- ing to the animal king- dom. If they are brought to rest by absence of proper moisture and temperature, they become changed into rounded masses, and secrete a cellu- lose wall. This is called the sclerotium stage. Upon re- turn of suitable conditions, the plasmodium form is again assumed. The reproductive stage is also one of rest; the mass becomes compact, heaped up into definite shapes (Fig. 233, I) surrounded by cellulose; the protoplasm within becomes separated into multitudes of spores (Fig. 233, V), which, in many species, are commingled with an irregular net-work of (often ornamented) filaments, called the capil- litium (Fig. 233, JIT, IV). Under proper conditions the Fig. 253. Arcyria pomiformis,a Slime-Mould; ¢, capi'litium; sf, sporangium ; J, plant, natural size; // and ///, magnified sixteen diameters; /V, capillitium; V, spores, more highly magnified, 124 SYSTEMATIC BOTANY. spores burst open, the protoplasm of each escapes as a swarm-spore with one cilium, and undergoes fission. Coa- lescence of a number of these takes place in a few days to form the plasmodium. 157. The Bacteria (Schizomycetes) are Protophyta, des- titute of chlorophyll. They are exceedingly small and simple organisms (Fig. 234), present in fermenting and putrefying matter, and sometimes in the blood of diseased animals, They occur isolated, or in cell-families, and multiply exclusively by transverse fission; most of them have a motile and a motionless stage. The unicellular Bacteria sometimes form a jelly-like mass or colony, probably in consequence of the swelling up of their cell- walls, and this is called the zodglea stage (Fig. 234, Bet). The common agent of putre- faction is Bacterium termo, which consists of very small cylindrical cells. B. wrugi- nosum is found in blue-green pus. The genus Micrococcus, consists of spherical cells (Fig. 234, Mier). M. prodig- wosus causes the blood-like patches on bread, paste, ete. M. dipthericus causes, or at least accompanies, diptheria. There are two genera, with filiform cells; Bacillus, with the filament straight (Fig. 234, Bel); and Vibrio, with the filament curved or undulated (Fig. 234, Vib). B. subtilis is the butyric ferment, and B. anthracis causes the anthrax or splenic fever. The genus Spirillum (Fig. 284, spl) has spirally twisted cells. 8. volutans is a comparatively large species with a flagellum or cilium at each end. Fig. 234. Bacteria; Micr, Micrococcus prodigiosus; Bet, Bacterium termo; Bel, Bacillus ulna; Vib, Vibrio rugula; Spl, Spirillum volutans; Spch, Spiro- chate plicatilis. PROTOPHYTA. 125 158. Another family of plants belonging to the Proto- phyta is the Saccharomyces, including the Yeast-plant (Saccharomyces cerevisie) and other species, which produce fermentation in sugar solutions. The transparent cells are more or less round, oval, or elongated, and multiply by budding & (Fig. 235). When the supply of nourishment 235 is less abundant (as when yeast is grown on slices of potato or carrot), the cells are larger, and divide internally into four new cells with cell-walls. These may be called spores ; they escape and grow into cells of the ordinary kind, capa- ble of multiplication by budding. Saccharomyces cerevisiae produces the alcholic fermentation; that is, the sugar in the solution is converted into alcohol with the escape of carbonic dioxide. S. ellipsoides, S. conglomerate, and others, live on grapes, and find their way into the juice in the manufacture of wine, and cause the fermentation of the latter. S. mycoderma is found on the surface of spoiled beer or wine; it does not produce fermentation like the others, but putrefaction instead. 159. Another family of the Protophyta containing (un- like the preceding) chlorophyll is the Nostocs (Nosto- cacee). The plants consist of rounded cells loosely united into filaments, and imbedded in a jelly-like mass (Fig. 236). At intervals are large, clear cells, called heterocysts, whose function is not clearly known. The plants grow in fresh water, or in damp places. They multiply usually by fission of the cells. Filaments sometimes break in pieces capable of motion; and from these, when at rest, new colonies are formed. The Fig. 235. Yeast-plant (Saccharomyces cerevisie). Fig. 286. A colony of Nostoc; the figure on the left moderately magnified ; the one on the right (a single filament) highly magnified. 126 SYSTEMATIC BOTANY. Oscillatoria have the cells of the filament more closely united. They form dark-green masses in water, or on wet earth, and exhibit an oscillating movement of the fila- ments. The Nostocs, Oscillatoria, with several other genera, as Rivularia, Scytonema, ete., have, in addition to chloro- phyll, a soluble coloring matter, called phycocyanine, and a less soluble one, called phycoxanthine. They are blue- green, verdigris-green, brownish-green, or even purple-red, and live in fresh or stagnant water, on damp ground) rocks, or decaying wood, ZYGOSPORES. 160. The second division, or Zygosporeze, is composed mostly of many-celled, filamentous organisms, but some of them are uni- cellular, and others a flat thalloid mass; nearly all of them contain chlo- rophyll, and are aquatic. They are the common Algee of our ponds and streams. The modes of reproduction are by (1) fission, (2) non-sexual spores (swarm-spores), and (8) zygo- spores. The swarm-spores (Fig. 287) are motile, naked masses of protoplasm, furnished with cilia. They escape from the cell in which they are produced, and after swim- ming about for a time, fuse two and two, and a spore with a thick wall is the result. Very simple, yet undoubted, sexual organs exist in the members of this group. The difference between the male and female organs, however, is not appreciable. The result of the union of the two sexual cells is the formation of a zygospore, with thick, firm walls; the process is illustrated in the Moulds (Fig. 238). Fig. 237, Swarm-spores, ZYGOSPOREZ, 197 Two small branches from the vegetative threads, or my- celium, unite end to end (Fig. 238, I); continue to grow larger (Fig. 238, IT); the terminal portion of each becomes separated hy a partition wall (Fig. 238, I7Z); the common wall between these cell-ends becomes absorbed (Fig. 238, IV); their contents fuse; a firm, thick cell-wall is secreted : and thus is formed the zygospore (Fig. 238, V), or rest- tmg-spore, as it is sometimes called, for it often remains quiescent and retains its vitality for a great length of time. 161. The Hydro- + dictyon, or Water-net, - ) Sa a fresh-water Alga, is ig , a representative of the —_ division, Zygospores. I. It sometimes occurs in abundance in ponds is composed of a multi- \' | tude of cells, arranged ANY \Q so as to form a tubular 238 net, whose meshes in the full-grown plant—when it may be eight or ten inches long—are plainly visible to the naked eye. It reproduces by the protoplasm of certain cells breaking up into several thousand small masses, or daughter-cells, which presently unite so as to form a minia- ture net; the wall of the mother-cell becomes absorbed, and the little plant is set free. It is said also to repro- duce by means of swarm-spores. The Desmids (Desmi- diacee) are motile unicellular fresh-water Alge (Figs. 239, 240), belonging also to this division. The cells are and slow streams. It | Fig. 238. Successive stages (J, J/, 77, 7V, V) in the formation of a zygospore in case of Mucor stolonifera. 128 ‘ §YSTEMATIC BOTANY. generally more or less con- stricted in the middle, and divided into two symmetri- cal half-cells. A sexual re- production takes place by the elongation and fission of the neck, uniting the two halves of the cells. The two small half-cells grow until they are as large as the original ones, when they separate. Sexual reproduction results in the formation of a zygospore; thus, elongations, or conjugating tubes, of two adjacent cells grow out till they meet, their protoplasm fuses upon the absorption of the partition between them, and this becomes covered with a thick wall, or exospore. 162. The Diatoms (Diatomacee), as are also the Desmids, are microscopic, unicellular Algee (Fig. 241), with a multi- tude of ornamental forms. They differ, however, in having silicious cells, and their chlorophyll concealed by a brown- ish or yellowish coloring matter, called phycowanthine. The cell (called a frustule) consists of two portions, called valves, one of which is slightly larger and fits over the other like the lid of a pill-box. Re- production takes place very similar to that in the Desmids, the protoplasm divides in a plane parallel to the valves, each portion secretes a shell or valve, which, in every case, is slightly smaller and fits into the old or outer valve. It is evident, therefore, that as multiplication by fission con- Fig. 239. Micrasterias furcata, a Desmid. Fig. 240. Cosmarium parvula, a Desmid. Fig. 241. Navicula viridis, a Diatom, ZYGOSPOREZE. 129 tinues, the resulting plants become smaller and smaller. When a certain limit is reached, reproduction by another process, namely, by auxospores (Gr. aurano, to increase), takes place, by which the original size is again attained; two plants approach each other, their valves separate, the protoplasm of the two fuses into one mass, and this grows to a large size, secretes a shell or valves of the normal form. Like the Desmids, the Diatoms loco- mote freely ; but the mech- anism of the process is not understood. They are ex- cessively abundant, and in- habit both salt and fresh water, often forming a yel- lowish layer at the bottom. As fossils they are also abundant, their silicified shells forming vast beds. Their beautiful and very fine markings make them desirable as test objects for the microscope. 163. Another very common, abundant and beautiful fresh-water Alga, belonging to the division Zygosporee, -is the Spirogyra (Fig. 242, 248). It is a many-celled, filamentous Alga, with the chlorophyll in spiral bands, and a eonspicuous nucleus in each cell, which is imbedded in the small central protoplasmic mass, and suspended by extensions to the parietal protoplasm (Fig. 242). The Fig. 242. A vegetative filament of Spirogyra. Fig. 243. Spirogyra in the process of conjugation. 9 130 SYSTEMATIC BOTANY. filaments elongate by the fission of the cells; the proto- plasm divides, a cellulose wall is at the same time secreted, and the two daughter-cells then elongate to the normal length. Sometimes the filaments break up spontaneously, and each part gives rise to a new filament. The sexual reproduction takes place by a process called conjugation (Fig. 243). From each of the cells of two filaments lying parallel to each other, slight protrusions arise (F ig. 243, 1), and these grow towards each other until they come in contact and unite we (Fig. 243, 2). The Ly : partition between Lp them becomes ab- _ sorbed (Fig. 243, 2) ; in the meantime, the protoplasm in each of the two cells con- - tracts, rounds itself, and one mass passes gradually through the channel (Fig. 248, 3) over into the other cell, where the two unite and form the zygospore (Fig. 248, sp). The old cell-walls decay, and the zygospore falls to the bottom of the water and remains till the process of germination commences. The latter begins by the bursting of the outer hard wall of the spore, the mass within extends in columnar form, secretes cross-partitions, and elongates to the normal form. 164. The common Fungi, called Moulds (Mucorini), Fig. 243a. Common Mould, partially diagrammatic; 4, hyphae; sf, sporangium ; 8, young sporangia. ZYGOSPOREL. 131 are also Zygosporee. They are saprophytic (or rarely parasitic), and, of course, destitute of chlorophyll. Their branching vegetative filaments, or hyphe, are numerous, and form a somewhat felted mass, or mycelium (Fig. 248a). Their vegetative, or non-sexual, reproduction takes place thus: erect hyphe are sent up from the mycelium, at the top of which a sporangium is formed by the terminal portion becoming enlarged and cut off by a partition wall (Fig. 244). This partition arches upwards, the terminal cell becomes larger (Fig. 245), and the former extends far up into the latter, and forms what is called a columella (Fig. 246, c). The protoplasm of the terminal cell, or sporangium, breaks up into a multitude of minute masses, each of which : becomes surrounded with a cell-wall, and thus the spores are formed. The latter germinate when on a proper nourishing substance, by sending out one or two hyphe, which soon branch and form a mycelium. The sexual reproduction of the Moulds has been illustrated in para- graph 160, above. The zygospore, after a period of rest and desiccation, will, in a moist atmosphere, send out hyphe, which do not form a mycelium, but produce spo- rangia, in which spores develop capable of germinating and forming a mycelium. Figs. 244-246. Diagrammatic representation of successive stages in the forma- tion of a sporangium in case of the Mould Mucor, 132 SYSTEMATIC BOTANY. OOSPORES. 165. The third division is the Oosporez, or plants characterized by the production of a large female cell, called the odgonium (Fig. 247, 0), in which is contained one or more round masses of protoplasm, the odspheres. These are fertilized by the contents of special, smaller male cells, called antheridia (Fig. 247, a). In some cases the protoplasm of the latter is transferred to the odsphere by direct contact; in other cases, it is first broken up into motile bodies, called spermatozoids, which approach and fuse with the odsphere. The désphere becomes the odspore, with a hard (and generally colored) covering, or exospore, and is capable of germinating after a certain period of rest. One mode of non-sexual reproduction in this group is presented by the genus Cidogonium, where large zodspores are produced (Fig. 248). Another mode is the formation of conidia, as in the White Rust ( Cystopus), where they are formed under the epidermis, and in the genus Peronospora (to which the potato disease, Perono- spora infestans, belongs), where they are produced on the ends of branching hyphe that grow through the stomates (Fig. 250). Fig. 247, Reproduction by the formation of an odspore in Peronospora Alsinea- runt; o, the odgonium; a, antheridium; s/, the odspore. OOSPORELZZ. 133 166. As a representative of the Odspore, the filament- ous fresh-water Alga, Gido- gonium, may be mentioned. It grows in ponds and streams, and forms green masses attached to sticks or other objects. When ex- amined under the micro- scope, a number of transverse parallel lines near one end of the cell will be seen, and in section they appear as so many cups slipped over each other (Fig. 249). This results from its peculiar mode of intercalary growth, as follows: an inward growth from the wall takes place in such a way as to form a cylindrical ring (Fig. 249, I). After a time, the cell-wall splits circularly through the exterior portion of the ring, and the two portions of the cell-wall recede from each other, connected by the unfolded cylinder (Fig. 249, IT). The cell elongates again by the formation of a new ring below the previous one, and so on. The non- sexual reproduction takes place by the formation of ciliated, motile zodspores (Fig. 248); when the spore (zodspore) comes to rest, and forms a cell-wall, it sends out root-like projections for attachment, then elongates, forms cross-partitions, and takes on the form of the adult filament. The a sexual reproduction takes place by the for- =| mation of an odsphere in an enlarged cell of eS ey hte - a the filament, the odgonium; this then opens, .and allows the entrance of the sperma- 249 tozoids, which have a crown of cilia, like Fig. 248. Non-sexual reproduction of CEdogonium. Fig. 249, Diagrammatic representation of intercalary growth of the idogonium, < 134 SYSTEMATIC BOTANY. the zodspores. The spermatozoids are produced in small cells which have arisen by simple fission of one of the larger cells. 167. Other representatives of the Odsporex are the uni- cellular Saprolegnia, and allied genera, which grow on dead fishes, cray-fishes, etc., and may be found parasitic on young, living fish in aquaria. They are often extremely abundant, and then cause immense losses in fish breeding. They multiply non-sexually by the production of ciliated zodspores, which are formed from the protoplasm in the end of a branch. The zodspores swim about for a few minutes, come to rest, their cilia disappear, and after a few hours they germinate by sending out a filament which produces a new plant. The sexual reproduction is by means of odgonia and antheridia. When the two arise on the same plant, fertilization takes place by direct con- tact of the antheridia with the odgonia, and the passage of the contents of the former into the latter through the tubular process of the antheridium. When the plants are dicecious, motile spermatozoids are produced for the pur- pose of fertilization. The odspores have a thick, double integument (exospore and endospore), and germinate by sending out a tube after a period of rest. 168. The Peronosporez (division Odsporese) deserve special attention on account of the great damage they do by their parasitism on living plants, and many of these are common in cultivation, as the Potato, Clover, Spinach, Grape-Vine, etc. The branching mycelium is unicellular, and grows into the tissue of the higher plants, sending minute branches, called hazstoria, into the cells themselves for nourishment. They multiply with great rapidity by non-sexual spores, called conidia. In the genus Cystopus, which may be seen on Shepherd’s-Purse, and other Cruci- OOSPOREE. 135 Jere, as white, blister-like patches, the conidia are produced just beneath the epidermis, which becomes ruptured, and allows their escape. In Peronospora, as the Grape-Mildew (P. viticola), the Potato Fungus (P. infestans), the white, frost-like down on Peppergrass (P. parasitica), etc., the conidia are produced on aerial branches of the hyphs growing from the stomates (Fig. 250). The conidia quickly germinate, and in some species give rise directly to a filament; in other species, swarm-spores, each with two cilia, are formed, which, after coming to rest, send out germinating filaments; these pass into the host-plant, either growing through the stomates, or boring directly through the epidermis, where numerous hyphe are again pro- duced. The sexual reproduction takes place by means of odgonia and antheridia (Fig. 247). 169. The Fucoidez are also sp, representatives of the Odsporese. in) They are marine Algz, whose e, green, or chlorophyll, is con- cealed by a reddish-brown color- ing matter. They are often of great size and present considerable differentiation of tissue, not found in the Thallophytes previously mentioned. They may be flat, or strap-shaped, and several yards in length, as in Laminaria ; they may be tree-like in form and size, twenty to thirty feet in height, as in Lessonia; or, like a gigantic pinnate leaf, sometimes more than three hundred feet long, as Macrocystis, The outer tissues are generally dense, and formed of small and crowded cells; the inner cells are mostly elongated and loosely joined, so as to 250 Fig. 250, Conidia of Peronospora; %, hyphze; sf, conidia; s/, stomates; gd, guard-cells. 136 SYSTEMATIC BOTANY. leave intercellular spaces. There is also considerable differentiation into reproductive organs, somewhat analo- gous to the floral branches in the higher plants. The repro- ductive organs, that is, oégonia and antheridia, are borne on modified branches, which differ more or less from the ordinary ones; they are generally contained in hollows (ealled conceptacles) of the epidermis. Some species are moneecious; others, dicecious. No non-sexual reproduction takes place. While most Thallophytes are short-lived, the plants of this group often live many years. The species of Fucus and Sargassum are washed ashore in great quanti- ties and used as a fertilizer for soil, and also for obtaining alkalies and iodine. Sargassum bacciferum is the Gulf weed, which covers a large area in the Atlantic, called the Sargasso Sea. CARPOSPORESZ. 170. The fourth division of the vegetable kingdom, viz, the Carposporee, is characterized by the produc- tion of a sporocarp, which consists in general of two parts: (1) a fertile part, which directly or indirectly produces the spores; and (2) a sterile part, which is com- posed of cells or tissue developed from the cells adjacent to the fertile part and envelopes the latter. Some of the representatives are chlorophyll-bearing, as the Red Marine Alge ; others are destitute of chlorophyll and parasitic, as . the Wheat Rust, Corn-Smut, ete.; or saprophytic, as the Toad-stools and Puff-balls. In the higher members of the group there is a considerable differentiation into eaulome (or stem) and phyllome (or leaf). The non-sexual repro- duction may take place by the production of (1) zodspores, (2) non-motile tetraspores (so called because they are mostly formed by the division of the mother-cell into CARPOSPOREE. 137 four parts or spores), or (3) conidia. The female organ in the sexual reproduction is called the carpogonium, and the male organ antheridium. Where two filaments cross each other, or come in contact, they enlarge (as in Spherotheca) ; one assumes an oval form, becomes separated from the filament by a partition, and represents the carpogonium (Fig. 251, car); the other grows up in contact with the carpogonium, cuts off a small terminal cell, the antheridium (Fig. 251, an). After fertilization the cells at the base of the reproductive organs grow upwards, unite, and com- pletely invest the carpogonium with a many-celled struct- ure, called the perithecium (Fig. 251, per). The carpogo- nium (Fig. 251, car) then undergoes cell-division, and from it one ascus (Fig. 251, as), or several (asci), are formed, which contain the spores, sometimes called ascospores. 171. The Florideze, or Red Algz of salt water, are chlorophyll-bearing representatives of the division Carpo- spore. The chlorophyll is concealed by a red pigment (ealled phycoérythrine), which is soluble in cold, fresh water. When it is extracted the plantsare green. These Algx are very numerous and beautiful; inhabit deep waters gener- ally ; and are, therefore, difficult to obtain for study. The Fig. 251. Successive stages (/, //, Z/I) in the development of the sporocarp in Spherotheca pannosa ; car, carpogonium ; az, antheridium; fer, peridium. 138 SYSTEMATIC BOTANY. non-sexual reproduction is by means of tetraspores. The carpogonium is peculiar in having a long filamentous appendage (trichogyne) to which the spermatozoids attach themselves when set free from the antheridium. Fertiliza- tion takes place in consequence of this contact, and the result is the production of the sporocarp. This, in some species, is very simple, and consists of the spores and the short branches which bear them; in others the mass is surrounded by a covering, or pericarp, developed from peripheral cells of the carpogonium. Some orders of the Florideze contain “ species which display the most exquisite combination of ramification and coloring.” The “ Dulse” (Rhodymenia palmata) is used as human food. The Irish Moss (Chondrus crispus) is extensively used also for food. 172. An exceedingly large and important group of the Carposporese is the so-called Ascomycetes. The plants are all destitute of chlorophyll, but differ among them- selves to great extent as to size and appearance. They are“ all alike, however, in producing their spores in sacs, called asci; the spores are, therefore, called ascospores. The following are the most important orders: 1. Erysiphacez. The plants of this order are mainly parasitic, and consist of a mass of branching, jointed fila- ments, which form a white web-like film on the surface of the leaves and stems on which they grow and from which they draw their nourishment. They are very abundant, and often do great injury to the Apple, Cherry, Grape, Pea, etc. The conidial spores are produced in great abundance during the summer. Later, the sexual repro- duction takes place in the manner described in paragraph 170 (Fig. 251). The sporocarp, or perithecium, has at its base radiating filaments, or appendages (ambulacra); they CARPOSPOREL, 139 are, in some cases, straight and prismatic, or they may be dichotomous, or hooked (Fig. rex 252) at the free ends. S 2. Pyronomycetes. This order differs from the preced- ing in having the asci em- bedded in deep cavities (called 252 perithecia) with narrow openings, instead of being com- pletely enclosed in perithecia. The pyronomycetous Fungi are very numerous, and exceedingly injurious not only to plants, but to insects also. A common representative is the Fungus (Claviceps purpurea ; Fig, 258), which produces the Ergot on Rye and other Grasses. In its earliest stage, it consists of a mass of myce- lium (Fig. 258, m), in and up- on the young ovary. Conidia (Fig. 253, con) are produced in great abundance, which quickly germinate. Follow- ing the conidial stage, the mycelium, at the base of the ovary (Fig. 253, ov), assumes a hard and compact form, increases in size, bears a horn-shaped and dark-colored body, the so-called Ergot. Such a compact mass of hy- phe is called a sclerotium. Fig. 252. The sporocarp (perithecium), with its appendages and two asci, of Uncinula macrospora. Fig. 253. Claviceps purpurea, the Fungus which pro duces the Ergot; 2, mycelium; com, conidia; ov, ovary. 140 SYSTEMATIC BOTANY. This sclerotium usually begins in the spring a new growth; little branches are produced, each with a globular head (Fig. 254, I), in the cortical region of which the numerous flask-shaped perithecia (Fig. 254, JI, IIT) are produced. The elongated asci (Fig. 254, III) bear attenuated spores (Fig. 254, sp), which germinate and produce the mycelium, which, in turn, infests the young ovaries as before. The 254 Black-Knot (Sphaeria morbosa) is another common and injurious Fungus of this order. 3. Lichenes. The Lichens (Figs. 255, 256) are consid- ered by most botanists to be ascomycetous Fungi, although formerly they were held to be an independent, isolated group. The tissue consists of an aggregation of colorless jointed hyphe, which, in the cortical portion, are usually Fig. 254. Claviceps purpurea (Ergot); successive stages in the development of the ascospores ; scZ, Ergot (sclerotium) ; per, perithecia ; 4, hyphe; sf, spores ; as, asci. CARPOSPOREZ. 141 compacted into a pseudo-parenchyma, and in the medul- lary portion distinct. Scattered through the interior, or disposed in one or more distinct layers, are numerous green, bluish-green, or brownish-green cells, called gonidia. These cells may be isolated, or in groups; or they may be rows, or chains of cells, and are capable of multiplication by fission. They are connected with the hyphz by one or more branches from the latter, or they may be united directly to an intermediate or terminal cell of the hyphe. The latter were, for a long time, supposed to produce them. Now it is held that the gonidia are simply imprisoned Alge, which assimilate the food to be appropri- ated by the Lichens—a peculiar kind of parasit- ism which seems to be mutually advantageous to the two plants. The reproduction is similar to the other Asco- mycetes (Fig. 256). The asci are either collected in a disk-like surface (gymnocarpous lichens), or enclosed in cavities or perithecia (angiocarpous lichens); and in either case called an apothecium. Of the numerous Lichens, a few furnish important commercial products; thus, from Roccella tinctoria, the dye orchil and “ litmus” are obtained ; and food is furnished by the Iceland Moss ( Cetraria island- ica), and others. The Reindeer Moss (Cladonia rangi- ferina) farnishes food to the reindeer. 4. Uredinez. The plants are parasitic in habit, and polymorphic; that is, in their life-course they take on at Fig. 255. Cladonia, a Lichen; a, the fruit, or apothecium. Fig. 256. Asci from the same, highly magnified. 142 SYSTEMATIC BOTANY. successive periods two or more distinct forms, so unlike each other generally that the different stages were formerly considered as distinct plants. Nothing is yet known as to their sexual organs. The mycelium penetrates between the cells in the tissue of leaves, causing abnormal growth and more or less distortion. There then appear, beneath the epidermis, globular masses (Fig. 257), having within at their base a compact layer of upright hyphe, each of which produces a chain of conidial spores The epidermis is ruptured by the growing mass ; and the thin layer of cells, or periderm (Fig. 257, p), enclosing the spores, breaks open; the yellow spores, hitherto many-sided from mutual pressure, become round and es- cape. This stage for- merly received the generic name of Acidium (Fig. 257). The spores may, therefore, be called the ccidiospores. There are often present also smaller flask-shaped repro- ductive bodies, called spermogonia (Fig. 257, sp), contain- ing hair-like filaments, which break up into exceedingly small bodies, called the spermatia. The exact function of these is not accurately known. The ecidiospores, when they fall on the proper host-plants, germinate, penetrate through the stomates, and form a dense mycelium in the parenchyma of the leaf; from this mycelium grow pedi- celled spores, called uredo-spores, and form, when they burst through the epidermis, orange-colored spots. This Fig. 257, Yellow Cluster-cup, or AXcidium (aec) of Puccinia graminis, and sper- mogonia (sf) on the Barberry leaf; e, epidermis; 4, peridium; sf, spermogonia, CARPOSPORELZL. 143 stage was formerly called the genus Uredo (Fig. 258). The uredo-spores germinate quickly, and from their mycelium other uredo-spores are produced, and this process may con- tinue a great length of time. Finally, from the same mycelium, are produced (Fig. 259) thick-walled, brown or black spores, called teleutospores (Gr. teleuta, end), which may be one-celled (as in Uromyces and Melamp- sora), two-celled (as in Puccinia, Fig. 259; and Podisoma, Fig. 258. Rust on Wheat (Puccinia graminis) ; section through the leaf, showing the uredo-spores (zz), highly magnified. Fig. 259. Rust on Corn (Puccinia sorght}; section through the leaf, showing teleutospores, highly magnified. 144 SYSTEMATIO BOTANY. Fig. 260), or many-celled (as in Phragmidium). They rupture the epidermis and become exposed, but generally remain attached to their host-plant during the winter. In the spring, they germinate by sending out from each cell a jointed filament, called the promycelium. In small branches of the promycelium, small terminal cells, or sporidia, are formed. These are carried about by the wind, and germinate on the proper host- plant. They send their filaments into the parenchyma of the leaf, from which a mycelium proceeds that gives rise to an secidium, and so on, as before described. In some species all the stages may grow on the same plant; more often the eci- dial stage is found on one plant, and the other stages on some other one; or, in yet other species, each stage may have a different host- plant. The Wheat Rust belongs to the second group; its eecidial stage occurs only on the Barberry leaves, and the uredo-spores and teleutospores are found on Wheat and other Gramineae. Fig. 260. Cedar-Apple, Gymnosporangium (or Podisoma) macropus, on Funi- perus Virginiana ; tel, teleutospores, highly magnified. CARPOSPOREZ. 145 5. Ustilagineze. The plants of this order are also parasitic; the mycelium ramifies through the tissue of the host-plant, and finally produces an abundance of brown, or black, thick-walled spores, which burst through the epidermis. The hyphe are jointed and branching, grow in the intercellular spaces, and also within the cell-cavities of their host-plants. The mycelium generally begins its growth when the host-plant is quite young, and grows with the latter. The spores are generally produced only in some definite part of the plant, as the young flowers (as in the smut of Wheat, Oats, etc.), ovaries (as in the bunt of Wheat), anthers (as in the smut of Silene), ete. In the smut of Indian Corn they may be formed in any part of the plant. The spores germinate, so far as have been observed, by producing a promycelium on which several sporidia are formed, much as in the Urediner. No sexual organs have as yet been detected. Many species of the genera U’stilago, Tilletia, and Urocystis are very destructive to Wheat, Oats, Corn, Grasses, Onions, etc. 173. The large and interesting Fungi, known as Puff balls and Toad-stools, are additional representatives of the Carposporese. But one kind of spores, and these non-sexual, are known, and they are produced on slender out-growths from the ends of enlarged cells, called basidia (Fig. 261, 6) ; for this reason the group is called the Basidiomycetes, The mycelium is mostly saprophytic, very abundant, and from it the spore-bearing growth, or sporocarp, is produced. The two important orders of this class are the Gasteromycetes and Hymenomycetes : 1. Gasteromycetes. The sporocarps in this order are usually more or less globular. The spores are borne within somewhat irregular cavities, from which they escape by the 10 146 SYSTEMATIC BOTANY. drying and rupture of the surrounding tissue. The basidia, upon each of which four or more spores are borne, are the rounded or elongated terminal cells of internal hyphe- branches. The outer wall (peridium) of the sporocarp ruptures irregularly in the common Puffball (Lycoperdon); but in the Earth-star ( Geas- ter), where it consists of } two layers, the outer, dense layer splits from the top into segments, which re-curve and ex- pose the inner and more delicate layer. This, in turn, ruptures somewhat irregularly, and allows the escape of the spores. The Giant Puffball (Lyco- perdon giganteum) is a very common and edi- ble species. 2. Hymenomy- cetes. The sporocarp, in the Fungi of this order, is composed of parallel, vertical hyphs, which grow up- wards, and (as in Agaricus) bend out laterally, or send out lateral branches at the top, to form the umbrella-like 261 Fig. 261. A Mushroom (Agaricus phalloides) ; J, the entire plant; ZZ, section of stem, or stipe; ///, gills, in transverse section; /V, longitudinal section, showing the gills, or lamelle; V7, a single lamella, moderately magnified; V7, a portion of the hymenium, highly magnified; V//, two basidia, with sterigmata and spores ; Pp, pileus, or cap; @, lamella; 4, hymenium; ¢, trama; J, basidia; sf, spores; st, sterigmata, CARPOSPORELE. 147 top or pileus (Fig. 261, p). On the under side of this are the gills, or lamella (Fig. 261, 7), upon whose surface there is developed a continuous spore-bearing layer, or hymenium (Fig. 261, 2). The hymenium consist of par- allel, compacted, elongated, subclavate cells (Fig. 261, h); on some of which, namely, the basidia, four (in some spe- cies only two) little pedicels (called sterigmata) arise (Fig. 261, st), and the ends of these enlarge and become con- verted into spores; called, therefore, basidiospores (Fig. 261, sp). These soon fall off and germinate, and (so far as is known) give rise to a mycelium. The most numerous and common representatives of this order belong to the genus Agaricus, which has several hundred species. Other common genera are Polyporus, in which the hymenium lines the walls of vertical pores on the under side of the pileus; Hydnum, in which the hymenium clothes numer- ous dependent spines ; and Stereum, in which the hymenium covers the smooth surface of the sporocorp. Many of the species are edible, and cultivated (as the Mushroom, Agavi- cus campestris) for food. It is said that Dr. M. A. Curtis found in North Carolina thirty-eight edible species of Agaricus, eleven of Boletus, nine of Polyporus, seven of Hydnum, and thirteen of Clavaria. Many of the common species are poisonous. 174. A small group of slender, submerged, aquatic chlorophyll-bearing plants, called Characew, should per- haps be mentioned, as additional representatives of the Carposporese. They have jointed stems, which bear whorls of leaves at regular intervals, The stems in cross-section are one-celled (as in Nitella), or they have a large axial cell, surrounded by many smaller ones, which form a corti- cal envelope (as in Chara), Under the microscope there is 148 SYSTEMATIC BOTANY. a manifest rotation of the protoplasm in the cells. The sexual organs differ somewhat from those of the Carpo- spores. The “central cell,” or carpogonium, is the terminal one of a row of cells; from the basal cells there grow upwards five elongated ones, which surround the carpo- gonium, and become twisted, so as to form a spiral. The antheridium is globular, enclosed by eight triangular cells, called shields, which are united by zigzag margins, From the centre of each shield, projects inwardly a cylindrical cell, which supports many long, coiled filaments, in each of whose numerous segments a long, slender, spiral, biciliate spermatozoid is produced. The spermatozoids escape, when ripe, by the bursting of the antheridium, and swim about in the water till they find the orifice at the upper end (or “ crown”) of the enveloping coat of the carpogonium. Upon their entrance, fertilization is effected, and the en- veloping cells become hard and dark-colored. ‘the fruit, or sporocarp, falls to the bottom, where it germinates when favorable conditions obtain; and a proembryo, consisting of a single row of cells, is formed, from which the sexual plant is developed by the growth of a lateral bud. BRYOPHYTA. 175. The Bryophyta (Mosses and Liverworts) con- stitute the fifth division of the vegetable kingdom. There is a well-marked alternation of sexual and non-sexual generations. The first, or that proceeding from the spore, bears the sexual organs, and is hence called the sexual generation. After fertilization, there grows a sporocarp (called sporangium), in which spores arise non-sexually ; this, therefore, is the non-sexual generation. The sexual organs of the Bryophyta consist of archegonia and anther- BRYOPHYTA. 149 idia. The archegonium is flask-shaped, in the bottom of which is a naked mass of protoplasm, the germ-cell, which is the essential part of the female organ. The antheridium is generally club-shaped, or sub-spherical, supported by a pedicel, and filled with many sperm-cells, each of which contains a single, spirally-coiled spermatozoid. The neck of the archegonium is open at the time of fertilization, and into it pass the free spermatozoids, which fuse with the germ-cell. Thereupon a thick wall, or covering, is formed, and cell-division in the germ-cell takes place. This, the spore-case (sporangium), supported by a pedicel, or seta, is nourished by the plant in which it is formed, but yet has no organic connection with it; and is, therefore, called the second, or non-sexual generation. Within the sporangium the spores are formed, and contain, besides colorless protoplasm, starch and drops of oil, also chloro- phyll grains. When ripe, the spore-case (as, for example, in Hypnum) opens by a more or less beaked lid, called the operculum (Fig. 262, op), which, in many species, is Fig. 262. A Moss; Dicranum glaucum; of, operculum; cal, calyptra; per, peristome ; sf, sporangium; s, seta: sf, spores, 150 SYSTEMATIC BOTANY. surmounted by a hood, éalled the calyptra (Fig. 262, cal) ; surrounding the orifice is a (single or double) row of teeth (Fig. 262, per), called the peristome (Gr. pert, around; stoma, mouth); the teeth number four, eight, sixteen, thirty-two, or sixty-four. The spores germinate by the rupture of the firm, outer coat, or exospore, and tube-like protrusion of the delicate, inner coat, or endospore, which, by division, gives risé to the filamentous proembryo, called protonema ; from this numerous buds arise, which give origin to the upright, leafy, sexual plants. 176. No true roots are produced by the Bryophyta; organs functionally (but not structurally) corresponding to them, are the rhizoids, or root-hairs, which grow from the under surface of the thallus, or from the sides of the stem. They serve to support the plant in its place, and also to absorb nourishment for its growth. The tissues are more differentiated than in previous groups. The epidermis is often quite well defined, and true stomates, absent in the lower groups, here appear. The tissue is mainly paren- chymous; but in the axial portions of the stem, and in the veins of the leaf, there is, by the elongated bundles of cells, slight indication of a fibro-vascular system. The two classes into which the Bryophyta are divided are (1) the Liverworts (Hepaticw) and (2) the Mosses (AMusct). 1. Hepatice. In this group, the Liverworts (Fig. 263), the plant-body is generally a true thallus, or thalloid structure, with only slight differentiation into stem and leaves. There are usually well-marked dorsal and ventral surfaces; when leaves are present, they consist of a simple layer of cells, with no midrib or other veins. The plants are small, of a bright green or brownish color, and grow in moist places on the ground, on rocks, or on the bark BRYOPHYTA. 151 of trees. Besides the sexual reproduction by means of archegonia and antheridia, they multiply extensively in a non-sexual manner; namely, by the production of peculiar buds, called gemme (Fig. 263, gem). These, in the common Liverwort (AJarchantia), are little cellular bodies, developed in cups, on the upper surface of the thallus. When the gemme are full-grown, they fall tothe ground, and grow directly into new plants. The stomates in these plants are not of the ordinary kind found in higher groups; instead of being surrounded, as there, by two guard-cells, there are sixteen (or more) cells, in four (or more) superposed layers, encircling the orifice, which leads into a large air-cavity below the epidermis. In this cavity are branching rows of cells, which contain the chlorophyll-masses (Fig. 264). 2. Musci. This group includes the Sphagnums and the true Mosses. The plants (Fig. 262) have stems, with sessile leaves and articu- lated root-hairs, or rhizoids ; the leaves are composed of a single layer of cells, and may, or may not, have a midrib. The stems may have an outer, thickened layer, or layers (imperfect scle- renchyma); and within, either simply thin-walled parenchyma, or an axial bundle of very narrow, thin-walled cells—imperfect fibro-vascular Fig. 263. A portion of a Liverwort, with the gemmez in cup-like cavities. Fig. 264. Section of a frond of Liverwort, showing the stomate (s¢) and the air-cavity (a) below, containing the cells which have the chlorophyll (ckZ). 152 SYSTEMATIC BOTANY. bundles. Stomates, like those of higher plants, occur only in the capsules, or sporangia. Most of the Mosses are aerial plants, growing on moist earth or rocks, upon the bark of trees, or occasionally in water; they are all chlo- rophyll-bearing, and usually of a light-green color. They sometimes multiply non-sexually, as in the Liverworts, by the production of geminz. These may be produced on the end of the stem; and when they fall off give rise to a kind of protonema, upon which buds arise, and develop. into the leafy plants. At times a protonema is formed from the leaves or root-hairs, and new plants then, in the ordinary way, are formed. The Peat Mosses (Sphagnum) are large, soft, and pale-colored plants, which grow in bogs and swampy places. The leaves are formed of two kinds of tissue, namely, of small cells, which contain chlo- rophyll; and of large perferated cells, destitute of chlo- rophyll, and containing water. By means of the latter, the plants are capable of taking up and retaining moist- ure, like a sponge. They are, therefore, useful material for “packing” in the transportation of living plants. Twenty or more species of Sphagnum occur in the United States. The true Mosses (Order, Bryacee) pre- sent the highest differentiation of tissue in the Bryophyta, and closely approach the Vascular Cryptogams (the next higher group). The genera are numerous, and have a wide, geographical distribution. In one sub-order, the spo- rangia, or capsule, is developed at the end of the main axis, and these are called the Acrocarpe (Gr. akron, top; karpos, fruit); common acrocarpous genera are Bryuwm, Minum, Polytrichum, ete. In the other sub-order, the fruits, or sporangia, are developed laterally, called, there- fore, Pleurocarpz (Gr. pleuron, side); Climacium, Hyp- num, ete., are common pleurocarpous genera. PTERIDOPHYTA. 153 PTERIDOPHYTA. 177. The sixth division, called Pteridophyta, include the Ferns (Fig. 265) and their allies. Here, as in the previous division, there is an alternation of sexual and non-sexual generations. But while the conspicuous gen- eration (the Moss) in the Bryophyta is sexual (and the inconspicuous, namely, the sporangium, non-sexual), the reverse is the case in the Pterido- phyta, that is, the conspicuous generation (the Fern, etc.) is non- sexual ; and the sexual generation, or stage, bearing the sexual repro- ductive organs (the prothallium) is very much reduced and short- lived. This prothallium is a small, flattened, thallus-like growth from the spore, composed of chlorophyll- bearing parenchymous cells, in one or a few layers; on its under sur- face are produced rhizoids, by which it is fixed to the ground. On the prothallia are developed the arche- gonia and antheridia, which are 265 essentially similar to those in the higher plants of the pre- ceding division. The spirally-coiled spermatozoids escape from the antheridium, enter the tube, or neck, of the archegonium, and fertilize the germ-cell therein con- tained. The result of this is the formation of a young plantlet, which develops into a leafy plant of considerable size, with marked differentiation of tissue, and capable of producing non-sexual spores. Fig. 265. A Fern (Camptosorus rhizophyllus); fr, frond; sor, sori; i, indu- sium; s$z, sporangium ; sfo, spores. 154 SYSTEMATIC BOTANY. 178. True roots first make their appearance in the Pteridophyta. They, like the stems, develop from a tri- angular apical cell (Fig. 266). This gives rise behind to the tissue of the root, and in front to the root-cap (Fig. 266, R.c). The three systems of tissue—epidermal, fibro- vascular, and fundamental—are well developed. The epi- dermis contains stomates of the ordinary kind. Trichomes, or hairs, are often abundantly developed, especially on young leaves, when they take the form of scurfy hairs, or scales. The fibro-vascular bundles are always closed. They generally contain tracheary, parenchymous, and sieve-tissue. The fundamental tissue consists of parenchyma, and sometimes also scleren- chyma; collenchyma and lati- ciferous tissue are seldom met with. The Pteridophyta are 266 divided into three classes: (1) the Horsetails, or Scouring Rushes (Equisetinew), (2) the Ferns (Filices), and (3) the Club-Mosses (Lycopodinec), 1. Equisetineze. The plants (non-sexual generation) of this class (called Horsetails, or Scouring Rushes) have a hollow-jointed, grooved stem, bearing at each node a whorl of narrow, united leaves, which form a sheath. The branches arise in the axils of the leaves, and are, there- fore, verticillate. There are underground perennial stems, which each year send up the vegetative and spore-bearing stems. The spores are produced in sporangia, which are modified leaves on the ends of the ordinary green stems, or on early colorless or brownish stems, which die as soon as Fig. 266. Diagrammatic section through the tip of a Fern root, showing the apical cell (af) and the root-cap (.c), PTERIDOPHYTA. 155 the spores are ripe. The modified spore-bearing leaves are peltate in form, and collected into cone-shaped clusters; in consequence of pressure each becomes hexagonal in outline; on the under surface of each peltate leaf, or scale, there arise several sac-shaped sporangia, which open at maturity by a slit on the side next to the pedicel, and allow the escape of the spores. “In their development the spores acquire three concentric coats, and as they approach matu- rity the outer one, which has previously become spirally thickened, splits, from two opposite points, into narrow spiral filaments, which are united with one another and the spore ata common point. These filaments are hygro- scopic, and they roll and unroll with the slightest changes in the moisture in the air; when moistened, they tightly wrap around the spore; but when dry, they unroll, and become more or less reflexed. By the changes of position which they undergo, they move the spores very consider- ably, and are doubtless useful in emptying the sporangia after dehiscence, hence they have been called elaters” (Gr. elater, driver). The epidermis of the Equisetinez contains a large amount of silica. The stomates are arranged in longitudinal rows—in the channels between the ridges. The fibro-vascular bundles are arranged in a circle surrounding the central cavity. Each bundle passes isolated down through the inter- node, and at the node divides into two short 2. branches, which unite right and left, with cor- responding branches of other bundles, thus forming the alternating bundles of the next lower internode (Fig. 267). The single bundle 267 from each leaf is applied at the point where the descending Fig. 267. Diagram, showing the course of the fibro-vascular bundles in the stem of Eguisetum. 156 SYSTEMATIC BOTANY. branches from the upper bundles unite to form the bundle in the lower internode. The class Equisetinese has but a single living genus, Equisetum, which contains about twenty-five species, most of them being small plants. In the Devonian and Carboniferous Ages there were many genera, forming an order Calamariee, which became extinct 4. in the Permian Period, 2. Filicine. The plants (non- sexual generation) of this class (Ferns) have a solid stem, with roots and broadly expanded leaves. They are mostly terrestrial, and all richly supplied with chloro- phyll. The spores are developed in sporangia on the surface or margins of the ordinary or modi- fied leaves. The leaves, called fronds, are circinate (Fig. 35) in their unfolding, and often divided and several times compound. On their under surface are the clusters 268 of sporangia, or sori (Fig. 268, sr). The sorus may be naked, or covered by a membrane, called the indusium (Fig. 268, in), which is of various shapes, and has various modes of attachment in the dif: ferent genera. The sporangia are generally roundish and pedicelled bodies. Each (in the Order Filices) is sur- rounded by an elastic ring (annulus), which contracts, and sets the spores free when ripe. The stems are mostly short, or creeping, but in the Tropics they are often of Fig. 268. A Fern (Camftosorus rhizophyollus); fr, frond; sor, §ori; iz, indu- sium; sfx, sporangium ; sfo, spore. PHANOGAMIA. 157 considerable thickness and height. They contain flat fibro- vascular bundles, usually arranged in a circle. When the stems become thick with increase of growth, a net-work of anastomosing bundles is formed in place of the central bundle. Ferns appeared in the Devonian Age, repre- sented by twelve genera, belonging to extinct families. In the Carboniferous Age they were much more numerous, but decreased to the present time. These plants are very ornamental, but otherwise of comparatively little value economically. The largest and commonest genera are Asplenium, Aspidium, Botrychium, Cystopteris, ete. 3. Lycopodinez. The stems of the Club-Mosses are solid, leafy, and mostly erect. The leaves are simple, small, sessile, imbricated, and resemble those of the Mosses. The spores are produced in sporangia, situated in the axils, and are appendages of the leaves. In some of the genera (Lycopodium, etc.) the spores are all alike; in others (Selaginella, etc.) there are two kinds—large spores (macrospores) and small spores (microspores). The plants of this class, now generally terrestrial, and only a few inches high, were numerous in the Devonian and Carbon- iferous Ages. Some of them (Lepidodendron, etc.; Fig. 345) were of gigantic size, but the order to which they belonged became extinct in the Permian Period. Several species of Lycopodium occur in the United States. Many species of Sedaginella, which are mostly tropical, are culti- vated for ornament. PHANOGAMIA. 179. The seventh and last division is called Pheenero- gamia, and includes all the common flowering plants; as herbs, shrubs, and trees. The reproductive organs (Fig. 158 SYSTEMATIC BOTANY. 269) are the stamens (Fig. 269, sta), which produce (in the authers) the pollen grains, the latter homologous with the microspores; and the pistils (Fig. 269, P), in which (ovary) the ovules are produced, which contain the embryo-sacs corre- sponding to the macrospores of the previous division. Enclos- ing and protecting these often grow special organs (slightly modified leaves), called the perianth ; or, when two whorls, corolla (Fig. 269, cor), and calyx (Fig. 269, cal). These, together with the stamens and pistils, and also the axial structure which bears them (Fig. 269, torus), constitute the Flower, whose development in general is as follows: At the end of a stem, protected and concealed by the small leaves, called bud-scales, arise minute papilla, or elevations, forming a peripheral whorl (Fig. 270). These are the first development of the outer- most floral organs, namely, sepals (Fig. 270, s). Imme- diately following them appear another whorl of similar papille (Fig. 271), situated within the first, and these represent the petals (Fig. 271, P). These two sets grow rapidly, arch over, and protect the essential organs which develop within. s s s NE s A SA P Ss Pap 2, 180. While the two ¢f) F an. 4 iy ? Ags 7 whorls described above %& : q are increasing in size, 271 272 278 athird whorl of papille — 979 Fig. 269. Longitudinal section of a flower; ca, calyx; cor, corolla; sep, sepals; pet, petals; sta, stamens; 4, pistil; ¢orws, torus; pedun, peduncle. Figs. 270- 273. Diagrammatic representations of the successive stages in the early develop- ment of a flower; s, sepals; A, petals ; a#, stamens ; J, pistil, PUZINOGAMIA. 159 (Fig. 272), immediately within the second whorl, makes its appearance. These blunt protu- berances (Fig. 272, an) develop later into stamens, with anthers, a portion of whose interior tissue undergoes repeated cell-division, and from it are formed isolated double-walled cells— the pollen grains. In the meantime, there has arisen within the innermost whorl, a circular elevation, or wall (composed of one or several parts, or carpellary leaves), which, arising and arching over at the top, forms a cavity (Fig. 278), destined to contain the ovules later developed from a point, or line (called the placenta, and correspond- ing to the edge of the carpellary leaf), on the inner side of this cavity, or ovary. This struct- ure, terminating the axis, is the pistil (Fig. 273, p). The ovule, at its first appearance, is a blunt protuberance (Fig. 274); after grow- ing to considerable size, an eleva- tion, or ring, near its base appears, and gradually grows as a covering, or integument (Fig. 275), over the nucleus or body of the ovule. In many cases a second integument arises, and in a similar manner encloses the first. At the apex an orifice, the micropyle (Fig. 275, m), invariably remains, which, Figs. 274, 275. Successive stages in the early development of the ovule. Fig. 276. Longitudinal section through an ovary and ovule; 4, pollen; 2, pollen-tube; ov.w, ovary wall; do/-¢z, pollen-tube ; 2c, micropyle; ow. 77, outer integument; zz, zz, inner integument ; ev. », embryo-sac; #wc, nucleus, or body of ovule. 160 SYSTEMATIC BOTANY. when fertilization is to take place, allows the entrance of the pollen-tube. 181. Simultaneously with the growth of the integuments is developed, near the upper end of the body, or nucleus of the ovule (Fig. 276), the embryo-sac (Fig. 276, em. s). This, when first distinguishable from the other tissue, zy consists of a cell somewhat larger than the adjacent ones. It then enlarges greatly ; voluminous vacu- oles appear, and the protoplasm con- -denses at the two extremities. In its apical portion, one or more roundish masses of protoplasm be- come differentiated, and these are the germ-cells, the impregnation of one of which results in the pro- duction of the embryo. The firm, outer coat of the pollen grain (Fig. 276, p) becomes ruptured upon absorption of moisture, the inner coat protrudes, and lengthens into a slender tube (Fig. 276, tw), which grows (Fig. 276, pol. tu) down through the micropyle (Fig. 276, mic) till it comes in contact with the embryo-sac (Fig. 276, em. s). Fertiliza- tion is the result of this contact, whereupon an embryo is formed (Fig. 277, 1). This consists of a short stem (caulicle, Fig. 277, caw), bearing one or more rudimentary leaves, called the cotyledons (Fig. 277, cot), at one end, and Fig. 277. Successive stages (/, 77, 7/7) in the development of the Bean plantlet; cot, cotyledons; caz, caulicle; AZ, plumule; rd, radicle; 2y, hypocotyledonary stem; /vs, the first set of leaves; /V, a portion of root, with root-hairs slightly magnified, PHZENOGAMIA. 161 a rudimentary root at the other (Fig. 277, rd). The embryo-sac develops within it a mass of cells, called the endosperm, at the expense of which the embryo, or rudimentary plantlet, grows. The ovules become much enlarged while the embryo is forming, and their outer coat generally becomes thickened and more or less hardened, At this stage it is called the Seed, and at maturity sepa- rates from the parent Pler plant. 182. After a period of rest, the seed, ex- posed to suitable condi- tions, germinates; that is, when proper tem- perature and moisture are supplied, it begins anew its development. It draws on the store of nourishment contained in the endosperm, or cotyledons ; the caulicle elongates ; the radicle, clothed with the root-cap (Fig. 277a, _ £.c.), grows downwards; and the stem, surmounted by the plumule (Fig. 277, J, pl), grows upwards. By the time the nourishment contained in the seed is exhausted, the -plantlet (Fig. 277, LIZ) is able to absorb food from the soil, and it develops by successive internodes into the adult form. The three tissue systems are well developed in the Pheenerogamia. The epidermis is supplied with numerous stomates; and trichomes of various forms are also copiously Fig. 277a. Section through the end of a root, highly magnified, and showing the root-cap (K.c.); 2, z, initial cells; D, dermatogen; fer, periblem; Pler, ple- rome. 11 162 SYSTEMATIC BOTANY. developed. The fibro-vascular bundles are either closed, or open, and consist of all kinds of tissue, except collen- chyma. The fundamental tissue is mostly parenchyma; but in the hypodermal portions it may contain collenchyma and sclerenchyma. In certain orders laticiferous tissue is also common. But few of the plants are parasitic or saprophytic; they are mostly chlorophyll-bearing. They vary in size from excessively small to excessively large plants, and in duration from a few days or weeks to hundreds of years. They are divided into two. classes, Gymnosperme and Angiosperme. , GYMNOSPERMZ. 183. The Gymnospermous plants, which include the Cycads, Pines, Firs, etc., have naked ovules, that is, not enclosed in an ovary; and the endosperm arises in the embryo-sac before fertilization takes place. They are all terrestrial, chlorophyll-bearing, and, with few exceptions, large trees. The flowers are always diclinous, that is, the staminate and pistillate organs are in different flowers. The pollen is transported by the wind (hence, the immense quantity produced) from the anthers to the ovules, whose orifice (micropyle) is at this time filled with a fluid. This drying carries the pollen grains down till they come in contact with the nucleus, or body of the ovule, when they germinate and produce pollen-tubes, which pierce the soft tissue, and reach the elongated bodies, called the corpus- cula (which seem to be homologous with the archegonia of previous divisions), which are developed in the embryo- sac; and the result of this contact is fertilization and consequent formation of the embryo-sac. This takes place as follows: The lower, or germ-cell of the corpusculum, GYMNOSPERILA. 163 gives rise, by the formation of a transverse partition, to a cell which is the rudiment of the suspensor. This grows and elongates, and at its lower end the embryo is formed ; the growing point (punctum vegetationis) is opposite to the suspensor; and near it, as lateral members, are produced the cotyledons. At the end next to and under the sus- pensor, a root, with a few-celled root-cap, is formed. The epidermal system consists of one or more layers of epi- dermal cells, frequently much thickened. The xylem portions of their fibro-vascular bundles are compacted into a dense woody cylinder, surrounded by the so-called bark or united phloém portions of the bundles. The generating tissue, or meristem, called , eF. cambiun, is situated between as the phloém (bast) and xy- (0) (0): CO 278 lem (wood). The mass of xylem is formed of trachei- des, with thickened walls and bordered pits (Fig. 278). The fundamental tissue consists of parenchyma in the inner portion (pith), which soon loses its vitality; the outer portion (cortex) consists of paren- chyma and sclerenchyma, or collenchyma; in it there is considerable development of cork. The narrow radiating plates of tissue (medullary rays) between the fibro-vascular bundles, are parenchymous in the young, and sclerenchy- mous in the older, stems. The medullary rays have cam- bium, called interfascicular cambium, corresponding in position and function with that of the fibro-vascular bundles. Most Gymnosperms have intercellular canals, filled with turpentine, containing dissolved resin. The class is divided into three orders, as follows: Cycads (Cycadece), Conifers (Conifere), and Joint Firs ( Gnetacec). Fig. 273, Bordered Pits, and diagrams representing their development. 164 SYSTEMATIC BOTANY. 1, Cycadez. The Cycads have simple (or rarely branched) stems, with large pith. They are large or small trees, with the general appearance of Palms and Tree Ferns. The stem is crowned with wide-spreading pinnate leaves. They are all tropical or sub-tropical species (about fifty or sixty), belonging to nine genera. One genus, Zamia, occurs in Florida. A kind of Sago is made from the starch in the roots of some species, and in some cases the seeds also are nutritious. The order originated in the Carbon- iferous Age, and in the Jurassic had twenty or more large genera. 2. Coniferze. The stems of Conifers (Pines, Firs, Junipers, and Yews) are branched, and usually resinous. The leaves are small, simple, and mostly crowded on the stem (Fig. 279), but sometimes scattered ; they are, in most of the species, persistent, ; and the trees are, therefore, evergreen. The “order contains thirty-three genera, and about three hundred species; about fifty of which are within the limits of the United States, Generally, the Conifers occur in the cooler regions of the globe. Economically, the order is of great value. Most of the Pines (Pinus) and Firs (Abies) furnish turpentine of varying quality, secreted in resin-passages (Fig. 280, r.c). Canada Balsam is obtained from the Balsam-Fir (Abies balsamea) of the United States; Venice Turpentine from the European Larch (Lariz Europea); Damar Resin from Dammara alba of the Malay Islands. The wood of many species, especially that of the White Pine (Pinus Fig. 279. Fascicled leaves of the Pine. GYMNOSPERMZ. 165 Strobus), is very valuable. Very many of the Cedars, Pines, Firs, Arbor Vitee, Yews, are very ornamental. The Big-tree of California (Sequoia gigantea), growing only on the western slopes of the Sierra Nevada mountains, attains a height of more than three hundred feet, and a diameter of twenty to thirty feet. 3. Gnetaceze. The Joint Firs are undershrubs, or small trees, and, except the peculiar Welwitschia, have jointed, rush-like stems, . and opposite, setaceous, or oval leaves. Unlike the previous Gymnos- perms the flowers have a perianth, or floral envelope. This may be single and bifid, or com- posed of two or more bract-like bodies (phyl- lomes). The order in- 280 cludes three genera, the most remarkable of which is the Welwitschia, which has but one species, growing in South Africa. Its trunk is a foot or two in diameter, and arises one foot above ground. There is a stout tap-root branch- ing below. The top of the stem is flattened with a depres- sion across its diameter. There are only two leaves arising from grooves, near the top of the stem; they seem to be the persistent cotyledons, and grow to be six feet long. Scarlet cones are produced on peduncles arising from the axis of the leaves. Fig. 280. Transverse section of a Pine leaf, highly magnified, showing the resin canal (7.c.); s¢, stomate; Ay, hypoderm; ché, chlorophyll; a, air-cavity. 166 SYSTEMATIC BOTANY. ANGIOSPERM:. 184. The second class of the Phenerogamia, namely, the Angiosperms, have ovules enclosed in an ovary; they are further distinguished from the Gymnosperms in having, as a rule, much more complex flowers. They are, in the great majority of cases, monoclinous (or hermaphro- dite); that is, the male (staminate) and female (pistillate) organs occur in the same flower. The floral axis generally remains very short; at its centre or top is situated the gynecium, as the pistils are collectively called, and imme- diately below, or without this whorl], is the whorl or whorls of stamens, which are denominated the andrecium. Sur- rounding these organs closely is generally found the perianth, consisting of one (calyx) or more (calyx and corolla) whorls of modified leaves. The latter are usually conspicuous and attractive (in entomophilous flowers) on account of size, color, odor, or honey secreted in the nectaries, which are usually present at their base. The pollen grains, transported from the anthers by various agencies to the viscid stigma, there germinate, or send down a tube through the loose tissue of the pistil which enters the micropyle of the ovule, and effects the fertiliza- tion of the latter. 185. The effect of fertilization is manifest as follows: The germ-cell (called also the embryonic vesicle), situated in the apical region of the embryo-sac, at once develops a cellulose-wall. It then divides transversely one or more times, giving rise to a row of cells, called the suspensor, or proembryo, and the lower end of this, by copious cell- multiplication, forms the embryo. There is, in the mean- time, “free cell-formation” of the protoplasm in the basal portion of the embryo-sac, by which the endosperm is ANGIOSPERMZE. 167 formed. The latter, increasing rapidly, fills the embryo-sac, and, besides, encroaches on and displaces, in most cases, the surrounding tissue. It is then more or less completely consumed in the further development of the embryo. After a many-celled body is formed at the lower end of the suspensor, or proembryo, partitions then arise in the cells, parallel to the surface; and thus is formed the pri- mary epidermis, or dermatogen. Simultaneously with this, there is also, as a rule, a differentiation of the inner cells foreshadowing the future tissue systems. A little later, either a depression in one side of the thallus-like structure is formed, which becomes the punctum vegetationis of the embryo, and the apical part extending beyond this point, the single cotyledon (Fig. 148); or instead, the apical point of the embryo becomes the punctum vegetationis, which is enclosed between the two cotyledons that grow out symmetrically from opposite points below, and adja- cent to the same. 186. The growing embryo, embedded in the nutrient endosperm, increases in size at the expense of the latter. In many cases it ceases its growth before all the endosperm is absorbed; as in the Crowfoots (Ranunculacee), Violets (Violacew), Palms (Palmacee), Grasses (Graminee), ete. Such seeds were formerly designated by the term albumin- ous. Otherwise, the embryo grows till it has absorbed and displaced the whole endosperm, storing its nutrient sub- stances in the much enlarged cotyledons, as in the Mustard family (Crucifere), the Roses (Rosacew), the Oaks (Cupu- lifere), ete. Seeds containing such an embryo were called exalbuminous. It happens in a few cases, for example, in the Water-Lily family (Nymphacee), that the endosperm is only slightly developed; in such cases the nutriment 168 SYSTEMATIC BOTANY. for the future growth of the embryo is largely stored up in the tissue of the ovule surrounding the embryo-sac, and this tissue is called perisperm. The ovary, as well as the ovule, usually undergoes great changes while the embryo is forming. The outer parenchymous coat of the ovule often becomes more or Jess sclerenchymous, and forms the testa; or it may become pulpy; in some cases it develops wings, or a tuft of hairs, etc. The ovary may become hard and dry, or pulpy. These two, called now seed and pericarp respectively, spontaneously separate at maturity from the parent plant. 187. The epidermis of the Angiosperms has commonly more stomates than that of the Gymnosperms. The tri- chomes, or hairs, are more often present, and exhibit a greater variation in form and structure. The fundamental tissue is abundant, and mostly parenchymous in the annual stemmed species; in the perennials there is less of it, and more of the fibro-vascular tissue. In these sclerenchyma is also usually developed. The chlorophyll-bearing paren- chyma of the leaf (mesophyll) is fundamental tissue; so also are the succulent parts of fruits. The fibro-vascular bundles are either closed or open, and their disposition for the most part is dependent on the position of the leaves. They are usually of the kind called “common bundles,” that is, they extend above into the leaf, and below into the stem. In a few cases there are “ cauline bundles,” or those in the stem which have no connection with the leaf Based on the number of cotyledons in the embryo, the structure of the stem, etc., the Angiosperms have been divided into two sub-classes, the Monocotyledones and the Dicotyledones. MONOCOTYLEDONES. 169 MONOCOTYLEDONES. 188. The Monocotyledones, so called since the em- bryo has alternate leaves, of which the first one developed is called a cotyledon, are also called Endogenz, or Endo- genous plants. A transverse section of the stem (Fig. 281) shows that the fibro- vascular bundles are isolated, numerous, 281 and scattered irregularly throughout the pith or funda- mental tissue. Each bundle is closed; that is, there is no zone of meristem tissue (cambium) between the xylem and phloém when these have reached their maturity, or passed over into permanent tissue. In consequence of ae this limitation of growth of the P\ i bundles, the plants are generally short-lived. In very young a | plants, where the fibro-vascular bundles are as yet few, their general disposition, or arrange- ment, may beseen. In the“ Palm 4 1 type,” which is illustrated in the accompanying diagram (Fig. 282), the leaves supposed to be opposite, and their bases united a l~|, with the entire circumference of the stem. The numerous bundles from each leaf pass obliquely lok into the stem, and then descend 282 through the latter. The middle Fig. 281. Transverse section of an endogenous stem. Fig. 282, Diagram show- ing the course of the fibro-vascular bundles in a stem from four successive leaves, in case of the “‘ Palm-type”’ 170 SYSTEMATIC BOTANY. bundle of each leaf (Fig. 282) passes deep towards the centre, and the lateral bundles (Fig. 282) curve downwards in the peripheral portions of the stem. There are many deviations from this type, especially by the bundles having lateral anastomosing branches. The fibro-vascular bundles (or veins) in the leaf are approximately parallel, passing usually from the base ‘to the apex (Fig. 283). The flower in the great major- ity of cases in the Monocotyledones, or Monocotyls, is three-parted; that is, each whorl consists of three mem- bers. As an example of the structure of the seed, the slightly magnified section of a grain of Indian Corn is given (Fig. 284). The germina- __ tion of the seed is shown in the fui" accompanying figure (Fig. 285). The sub-class is represented by about fifty natural orders, of which the following are interesting or important: 1. Graminez. The Grasses are herbaceous, or rarely woody, plants, with round, jointed, and (mostly) hollow stems, which have alternate two-ranked leaves. The leaf below is a split sheath (Fig. 286); above, a narrow, elongated part, called the lamina; and at the junction of these two there is a Fig. 283. A parallel-veined leaf, Fig. 284. Section of a grain of Indian Corn; cat, cotyledon; A7, plumule ; 7, radicle ; 7.c, root-cap; e, endosperm, MONOCOTYLEDONES. 171 membranous outgrowth, called the ligule. The flowers are in spikes, racemes, or panicles, consisting mostly of numerous spikelets; each of the latter is surrounded at the base by two glumes (Fig. 287), above which are the flowers. The pro- tecting organs, or perianth, consist of an upper palet (Fig. [jf 288) andlower palet [4 (Fig. 288, lp); with- fll in are the (mostly Ba three) stamens, with jf slender filamentsand fd versatile anthers. 286 The ovary is simple, contains one ovule, and has two styles, mostly with feathery stigmas (Fig. 289). The fruit is a grain, or caryopsis. @ This is a very natural and large 3 order, containing about six thousand species, to be found in all climates. All other orders of plants , combined probably do not ( fle contribute more to the V4 sustenance of man than NY a the Gramineze. Wheat (Zritieum vulgare), 3’ \Y/” probably a native of Asia, has been in culti- x2 vation from time immemorial. Remains of 287 Fig. 285. Successive stages in the germination of Wheat; 7, roots; s, soil-parti- cles; st, stem. Fig. 286. Leaf of Grass. Fig. 287. Spikelet of Grass-flowers; e@, glumes; ffs, flowers ; A, palets. 172 SYSTEMATIC BOTANY. wheat-grains have been found in the pre-historic Lake Dwellings of Switzerland. Under the influence of cultivation, innumerable 2p. “ varieties” have arisen, differing much as to the color and quality of the grain, XP Pal presence or absence of awns, as to the hardiness of the plant, ete. Barley (Hordeum distichum and H. hexasti- chum, two-rowed and six-rowed Barley) 288 is now used in making bread; it was cultivated in remote times The Rye (Secale cereale) has also been cultivated for ages, originating probably in Southern Europe and Asia. Rice ( Oryza sativa), cultivated in many countries, furnishes food to more human beings than any other plant. Indian Corn, or Maize (Zea Mais), anative of the warm regions of the New World, was cultivated by the aborigines of North and South America. Under its extensive cultivation many “varieties” have arisen. The Oat (Avena sativa), grown more especially in cooler climates, probably originated in North Europe or Asia. Among the important forage Grasses are the Timothy, or Herd’s Grass (Phleum pratense), Red-top (Agrostis vulgaris), Orchard Grass (Dactylis glomerata), all natives of Europe; also Kentucky Blue Grass (Poa pratensis) of the United States ‘S and Europe, and Slough Grass (Muhlenbergia * glomerata and M. Mexicana) of the Missis- sippi Valley. The Sugar-Cane (Saccharum oficinarum) is a native of the warm regions of Asia, and is cultivated in all warm regions 289 Fig. 288. A gramineous flower (Poa pratensis); up pal, upper palet; 24, lower palet. Fig, 289. Feathery stigma of Poa pratensis, MONOCOTYLEDONES. 173 of the world. From its sweet juice most of the sugar and molasses of commerce is made. The Chinese Sugar-Cane (Sorghum vulgare) has lately been introduced into the United States, and from it molasses and sugar are made. The Broom-Corn, used in the manufacture of brooms, is a variety of this. The Bamboo (Bambusa arundinacea), sometimes attaining the height of even one hundred feet, has innumerable uses in India, where it is employed in manufacturing ornamental trinkets, house building, fences, water-pipes, and various other things. 2. Cyperacez. The Sedges differ from the Grasses in having solid, three-angled stems, three-ranked leaves with entire sheaths. The spiked flowers have no perianth, or only hypogynous sete, or a cup-shaped or sac-shaped perigynium. Stamens mostly three, pistil simple, and fruit autricle. The order comprises about two thousand widely distributed species. They never form continuous mats like most of the Grasses, but grow in tufts, preferably in wet places. As forage plants they are very inferior, or mostly quite unfit. A Sedge (Cyperus textilis) is used in India for making ropes and mats; and other species are used in Egypt for the same purpose. The Bulrush (Scirpus lacustris) of Europe and Asia is used extensively in making mats, ropes, chair-bottoms, and hassocks. The Papyrus (Papyrus antiquorum) of Egypt and adjacent countries, a tall plant, diameter one inch, was used in ancient times for making paper. This was done by slicing the cellular pith, and then hammering and smoothing it. A Carex, or true Sedge (Carex arenaria), has deep and extensive roots, grows in tufts, and binds the soil of the dikes and the moving sands of the sea-shore. 174 SYSTEMATIC BOTANY. 3. Juncaceze. The Rushes grow in temperate and cold regions. They are herbaceous and grass-like, often leafless, with inconspicuous green or dry flowers. The perianth is glume-like, six-parted, stamens six (or three), and pistil three-carpelled. The order includes about two hundred’ and fifty species of which the Rushes (Juncus) are used extensively in making mats, chair-bottoms, baskets, hassocks, ete. A curious aquatic plant of South Africa, with serrated leaves two or three feet long, has a stem, composed of a firm fibre, capable of conversion into paper; it has been also used for brushes. The Asphodel (Narthecium ossifragum) is cultivated for ornament. 4. Liliaceze. The Lily family contains mostly herba- ceous plants, with showy flowers and entire leaves. The flowers are perfect, regular, and six-parted (rarely four- parted), stamens perigynous, ovary superior, and fruit a capsule or berry. There are about two thousand species found in all climates; some of them furnish food, others medicine, and many of them are very fine ornamental plants. The Onion (Allium Cepa), from the Mediterra- nean region, is cultivated all over the world. Asparagus (Asparagus officinalis), native of Europe and Asia, was cultivated by the Romans before the Christian Era. In this long period of cultivation it has exhibited but little variation. The curious Grass Gum-trees (Xanthorrhea) of Australia, six to ten feet high, with grass-like leaves, yield a fragrant resin, and contain an abundance of ‘picric acid. The latter is used in dyeing silk and wool yellow. The gum resin is made into candles, used in some churches asincense. Aloés is the inspissated juice of several species of Aloe. This genus contains about one hundred and fifty species, mostly from South Africa and adjacent islands, MONOCOTYLEDONES. 175 Many species are cultivated. Several species of Smilax (Smilax officinalis, etc.) of South America furnish sarsa- parilla root. The Squill (Scilla maritima) comes from the sandy regions of the Mediterranean ; its sliced bulbs form the dry squill. The Lily of the Valley (Convallaria majalis) is a native of Europe and Asia. The Crown Imperial (Fritillaria imperialis) of Europe and Asia, and the Day-Lilies (Hemerocallis flava, and H. fulva) of Europe, are coarse, ornamental plants. The Hyacinth (Hyacinthus orientalis), a native of Asia Minor, was intro- duced into England before the end of the sixteenth century; and under cultivation, has developed many varieties. Of the true Lilies (Lilium), the following are most common in cultivation: The Orange Lily (ZL. bul biferum), Tiger Lily (L. tigrinun), the Turban Lily (Z. Pomponium), the Golden Lily (Z. auratum), the White Lily (L. candidum). A deli- cate climber in conservatories, called Smilax (Myrsiphyllum @y asparagoides), is from the Cape of Good Hope. The Star-of-Bethlehem (Ornitho- galum umbellatum) from Europe, the Tube Rose (Poh- anthes tuberosa) from the East Indies, are also common in cultivation. The Tulip (Tu- 2 ; lipa Gesneriana), whose spe- cific name was given in honor of the botanist Conrad Gesner, who was the first to describe and figure it (in 1559), was brought into Europe Fig. 290. A cultivated species of Yucca. 176 SYSTEMATIC BOTANY. more than three hundred years ago. The Dutch improved it very much; and single bulbs of choice varieties sold at enormous prices. The original yellow flowers have been greatly enlarged. Several species of Yucca (Fig. 290), a genus from Mexico and adjacent regions, are found in cultivation, as Adam’s Needle, Spanish Bayonet, Bear- Grass, ete. 5. Lemnacez. The Duckweeds are the smallest of the Phenogams; they consist of floating parenchymous disks, with several or one (Lemna), or no ( Wolffia) roots beneath. Their flower-clusters are sunken into pits in the top, or edge, of the disks, and have one or two stamens and one pistil, each representing a flower. There are about twenty species, widely distributed in the Northern Hemi- sphere. 6. Aroideze. The Arum family includes mainly tropical herbs, which are often large and palm-like, with large leaves, having reticulated vena- tion, and the flower-cluster usually sur- rounded by a spathe. The flowers are borne on a spadix (Fig. 291); the. ‘ perianth consists of from four to six scales, or is wanting; stamens hypo- gynous;-stigma sessile; fruit baccate (or dry). There are about one thou- sand species of Aroids, some of which attain a height of from six to twelve feet; one recently discovered in Suma- tra (Amorphophallus Titanum) has a spathe six feet in depth, and two and a half feet in diam- eter. The Indian Turnip (Arisema triphyllum, and A. Fig. 291. Spathe and spadix of Indian Turnip, MONOCOTYLEDONES. 177 Dracontium) and Sweet Flag (Acorus Calamus) are medi- cinal. The Calla, or Ethiopian Lily (Richardia Africana), native of Africa, has been in cultivation about one hundred and fifty years. Recently, species of Alocasia and Caladium have been introduced as hot-house plants. The Skunk Cabbage (Symplocarpus fetidus) belongs to this family. 7. Palmacez. The Palm family includes trees, shrubs, or woody climbers, with the monecious or dicecious flowers in a spadix (or a panicle or spike), generally enclosed in a hard, or leathery spathe. The perianth is six-parted; sta- mens six; pistil of three carpellary leaves; fruit a berry, or stone-fruit. The plants occur in the Tropics, or adjacent warm regions. No plants are more majestic than the arbo- reous species, which rise often to the height of one hundred feet, bearing at their summit spreading crowns of large leaves and drooping clusters of fruit. There are nearly a thousand species; and, except the Grasses, no family of plants surpasses them in the importance of their products. An arboreous Brazilian species (Atalea funifera) furnishes in its fibrous leaves material for making ropes, mats, and coarse brooms; the hard nuts (Coquilla-nuts), about three inches long, are used for making door-handles, bell-pulls, ete. The Cocoa-nut Palm (Cocos nucifera) is a native of the coasts of Tropical Africa, India, and Malay, and culti- vated in all tropical countries. It produces the cocoa-nuts of commerce; each tree may yield one hundred to one hundred and fifty nuts annually, and continue to bear forty years. The white albumen and the milk furnish the natives of some parts of India and other countries with nearly their entire food and drink. The uses of the various parts of this tree are manifold, as in constructing huts, 12 178 SYSTEMATIC BOTANY. fences, baskets, ropes, making drums and ornaments. The tender terminal bud is highly prized for food. From the juice of the flower-stems, rich in sugar, by fermentation, wine is made; and by distillation, a spirit is produced, called arrack. The fibre from the sheaths (leaves) is made into “coir” rope, floor-matting, brushes, and brooms; and is used also for stuffing cushions. The Palm (Eiqis guineénsis) of West Africa produces nuts, from which is manufactured palm oil, used in the manufacture of candles, soap, ete. The Wax Palm ( Copernica cerifera) of Brazil furnishes a wood which takes a fine polish, and is used for veneering, and a waxy secretion (on the leaves) used for making candles. For ages the Date Palm (Phenix dac- tylifera) has been cultivated in Arabia and North Africa, and furnishes a large portion of the food of the people of these countries. The Dates are also imported into the United States, after having been picked before quite ripe and dried in the sun. The Ginger-bread Palm (Hyphene thebatea) is a branching species of the upper Nile region, which produces fruits the size of an apple, with the flavor of ginger-bread. The tree furnishes a resin called Egypt- jan Bdellium. achenium. (333) 334 GLOSSARY. Ala: wing or side petal of a Papilionaceous corolla. Alaie: winged. Albumen: endosperm or reserve material stored in the seed. Albuminous: having an endosperm or reserve material stored in the seed outside of the embryo. Alburnum : sap-wood. Aleurone: albuminous granular bodies in seeds, having the same reaction as protoplasm. Alliaceous: like the Onion (Allium). Alpine: growing on mountains. Alternate: one above, or between, the other. Alveolate: with pits like honey-comb. Ament, or Catkin: a scaly spike of flowers. Amentaceous: having aments or catkins. Amorphous: without definite form; not crystalline. Amphicarpous: having fruit of two kinds. Amphigastria : the small leaves or scales on the underside of Liver- worts. Amphitropous ovule: inverted, with a short raphe, and the hilum near the middle of one side. Amplexicaul: clasping the stem. Amylaceous : starchy. Analogy : resemblance as to function. Anastomosing : uniting end to end, and forming a net-work, as veins. Anatropous ovule: inverted, so the hilum is close to the orifice and the chalaza at the top. Andrecium: the stamens taken collectively. Anemophilous flowers: those whose fertilization (or pollination) is effected by the agency of the wind. Angiocarpous : with the hymenium (or spore-bearing layer) immersed in a cavity (perithecium). Angiosperm: an angiospermous plant, or one with an ovary. Angtospermous: with seeds in ovaries. Angular divergence: the angle formed by vertical planes passing through the leaves and the centre of the stem. Annual: yearly; living but one year; fruiting and dying the first year. Annular: ringed; having rings; ring-shaped. Annulus: the thickened ring in sporangia of many Ferns, and at the mouth of the spore-cases of Mosses. Anther: the part of the stamen which contains the pollen. Antheridium: the male reproductive organ in Cryptogams, whose function corresponds to that of stamens in Pheenogams, Antheriferous: bearing anthers. Anthesis: flowering; the time or act of flowering. Antispasmodic: that which prevents spasms or convulsions. Apetalous : without petals. Apex: the top; the point of the leaf opposite the petiole. Aphyllous: destitute of leaves. Apical: pertaining to the apex. GLOSSARY. 335 Apocarpous: when carpels of a gynezcium are separate, as in anunculus. Apothecium : the reproductive part or sporocarp of a Lichen. Appendage, or Appendiz: a part which is added; a projection. Appendiculate: having an appendage. Appressed: close pressed ; as leaves, etc., to the stem. Apterous: destitute of wings. Aquatic: growing in water. Arachnoid: like a spider’s web; clothed with soft fibres. Arbor: tree Arboreous: like a tree; dendritic. Arborescent: almost a tree; growing into a tree. Arboretum: a place in which a collection of trees is cultivated. Archegonium : the flask-shaped reproductive organ of Mosses, Ferns, ete., corresponding in function to a pistil. Arcuate: curved like a bow. Areolate: having small spaces, or areole marked out. Areolation : smal] spaces bounded by veins of leaves, or cell-walls, etc. Argentate : resembling silver. Arillate: having an aril. Aril: a fleshy growth (like a third integument) more or less cover- ing the seed. Arista: awn; beard of Wheat, Barley, etc. Aristate: having an awn or long bristle. Articulated: jointed; having joints or articulations. Artificial classification: that which is based on one or a few characters regardless of affinity. Ascus: the cell or sac in which the spores arise in some Fungi (Ascomycetes). Assimilation : conversion of inorganic into organic matter. Assurgent: ascending or rising obliquely. Astichous: not in rows. j Atropous: orthotropous ; not bent. Attenuate: long drawn out. Auricle : an appendage, or expansion somewhat ear-shaped. Auriculate: having ear-like appendages. Autogamy : close-fertilization, or the fertilization of the ovules by the pollen of the same flower. Auzospore: the spore resulting from copulation in Desmids, and by which the individual is increased in size. Awn: beard of Wheat, Barley, Grasses, etc. (Arista.) Avil: the angle formed by the leaf and stem. Axillary: in the axil; belonging to the axil. Axis: the root and stem; a central organ to which others are attached ; central line. Baccate: like a berry; pulpy like a berry. Banner : the upper petal of a Papilionaceous corolla (vexillum). Barbed: having a barb or double hook; with projecting hooks or prickles. 836 GLOSSARY. Barbellate: having short, stiff hairs, as the pappus of some Com- ositee. Bark: Thay part of the stem or trunk external to the wood. Basal: attached or belonging to the base. Base: that part of an organ by which it is attached. Busidiospore: a spore, as in the Mushrooms, which is supported by a little pedicel of the basidium. Basidiuwm: the enlarged terminal portion of the hymenial hyphe, bearing spores on sterigmata. Basipetal : towards or approaching the base. Bast, or Bass: the inner fibrous bark. Bast-cells : the long-pointed thick-walled cells of bast. Beaked: terminating by a long narrow tip or beak. Berry: a pulpy or juicy fruit. ; Bi, or fae a prefix): two; as bilobed (two-lobed), bifid (two- cleft). Biennial: lasting two years ; fruiting and dying the second year. Bifid: two-cleft to near the middle. Bifoliate : with two leaflets. Bifurcate : forked into two branches ; twice forked. Bilabiate : two-lipped (labiate). Bilocular : two-celled, or having two cavities, Binary : composed of two elements ; in two’s. Binomial nomenclature: naming by two (the generic and specific) names. Biology : the science which treats of plants and animals, Bipartite: two-parted. Bipinnate : twice pinnate. Bipinnatiid : twice pinnatifid. Bisected: cut in two; divided in two parts. Biseptate: having two partitions. Bisexual: having both stamens and pistils (hermaphrodite), Bisulcate : two-grooved ; having two furrows. Blade: the thin expanded portion of a leaf (lamina). Bloom: the fine white powder (of wax) on some leaves. Botanical Province: a geographical region having characteristic groups of plants, Botany : the science which treats of plants. Botryose: of the racemose type. Bract: small leaf or scale from whose axil a flower or pedicel pro- ceeds ; the reduced leaves in a flower-cluster, ete. Bracteate: having bracts. Bracteolate : having bractlets, Bractlet : the bract or scale situated on the pedicel. Branches: the divisions of a stem or trunk; limbs. Branchlets: very small branches; divisions of a branch. Breathing pores: stomates. Bristle: stiff, sharp hair. Bristly : having bristles. Bryology : that division of botany which treats of Mosses. GLOSSARY. 337 Bryophyta: the division including the Mosses and Liverworts. Bud: the undeveloped branch; the “growing point” with its covering of scales, Budding: producing an outgrowth by some Cryptogamous plants, which separates and grows into a furm like the parent, Bud-scales : the scales or modified leaves of a bud. Bulb : a shortened axis or bud with fleshy scales. Bulbijerous : bearing bulbs. Bulblet : small bulbs above ground; as in axils of Lily. Bulbous: bulb-like. Bullate: blistery or bladdery. Caducous: falling off very early. Callose : hardened ; having callosities. Calycine: belonging to the calyx. Calyculate: having an additional outer calyx, or calyx-like bracts. Calyptra: the hood or covering over the operculum of Moss capsules. Calyx: the outer whorl of the floral envelopes; the sepals taken collectively. Cambium: the generating tissue between the wood (Xylem), and bark or bast (Phloém). Cambium zone: the continuous layer of cambium surrounding the wood in Exogens. Campanulate: bell-shaped. Campylotropous ovule: curved upon itself so that the micropyle is brought towards the funiculus. Canaliculate : channeled or with a long groove. Cancellate : like lattice-work. Canescent : grayish-white. Capitate: with a globular apex; forming a head. Capsule: a pod; any seed or spore vessel. Carina: keel; the two lower (anterior) petals of a Papilionaceous flower, joined so as to be keel or prow-like. Carinate: keeled. Carminative: remedy for colic, or expelling wind from the body. Carpel: a simple pistil, or one of the parts or leaves of which a compound pistil is composed. Carpellary: pertaining to a carpel, or part or leaf of which a com- sound pistil is composed. Carposporee : a division of the vegetable kingdom characterized by the formation of a sporocarp. Caryophyllaceous : pink-like. Caryopsis: the grain or one-seeded fruit of Grasses. Cataclasm : poultice. Catkin : a scaly spike of flowers (ament). Caudate: tailed ; pointed like a tail. Caudex: a trunk like that of Palms; an upright root-stock. Cnudicle : the little stem or pedicel of pollinia (pollen masses). Caulescent : having an evident stem. Caulicle: the rudimentary axis of the embryo. 22 338 GLOSSARY. Cauline: pertaining or belonging to the stem. Cauline bundles: those fibro-vascular bundles in the stem which haye no connection with those in the leaf. Caulome: that which answers in general to a stem. Cell: the minute body consisting of a wall or membrane enclosing protoplasm, etc., which is the proximate constituent element of vegetable tissue; a vessel or cavity, as anther-cell. Cellular : consisting of cells. Cellulose: the substance of the cell-wall or cell-membrane. Centrifugal : from the centre outwards. Centripetal : towards the centre. Cereal: pertaining to the grains; as Wheat, Rye, etc. Cernuous : nodding. Chaff: the bristles or scales on the receptacle of Composite; the glumes of Grasses, Chalaza: the point of the ovule where the integuments and nucleus unite. Channeled : hollowed out like a gutter; furrowed. Character: any distinguishing point or property. CHorophyll: the green coloring substance in plant-cells. Choripetalous: with petals not united with each other. Chorisepalous : with sepals not united with each other. Cicatriz: a scar left by the fall of a leaf or other organ. Cilia: long hairs like eye-lashes ; hair-like prolongations of proto- lasm. Ciliate: fringed with cilia, hairs, or bristles. Cinereous : ash-gray. Circinate (or Circinnate) : rolled inwards from the top. Circulation of protoplasm: a streaming or current movement in the protoplasm in cells. Circumscissile : divided by a circular line around the sides. Cirrhiferous : bearing tendrils. Cirrhose: bearing tendrils. Clavate : club-shaped ; thickened above. Class: a group; one of the groups which form a division ; as class Gymnosperms, of division Phenogams. Classification : grouping, or putting in groups or classes. Claw: the creed base or stem-like part of some petals. Cleistogamy : close-fertilization in unopened flowers. ne characterized by cleistogamy. leistogamic : pertaining to cleistogamy; exhibiting cleisto; s Cleft divided almost ‘eB the middie, a s aw Closed-bundles : fibro- vascular bundles destitute of cambium. een : fertilization of the ovules by pollen of the same ower. Club-shaped : clavate; thickened above. Clypeate : shaped like a buckler. Coalescent : growing together. Ceenobium ; a cell colony ; cells loosely united into a family, Coherent ; connate ;. growing together of like parts. GLOSSARY. 839 Cohesion : union of like parts or organs; as petals with each other. Cohort : a division of a sub-class; as Cohort Glumales (Grasses and Sedges of sub-class Monocotyledons). Coleorhiza: the root-cap. Collar, Collum: the point of junction of stem and root. Collenchyma: tissue whose cells are thickened at the corners and situated under the epidermis, Colored: not green. Columella: the slender, elongated torus, as in Geranium; the central column of a sporangium or capsule. Column: the tube of monadelphous stamens; the body formed by the union of stamens and pistil, as in Orchids. Coma: a tuft; a tuft of hairs. Cunmesees the face by which two carpels cohere; as in Umbel- iferse. Common bundles : those fibro-vascular bundles which pass below into the stem, and above into the leaf. Complanate: flattened. Complete Liss : one having the four parts—calyx, corolla, stamens, and pistil. : Complicate: folded upon itself. Composite flower : one which consists of a head of florets, as in Com- positee. Compound : not single ; composed of several parts. Compressed : flattened lengthwise, or on two opposite sides. Conceptacle : cavities in the tissue in which the reproductive organs are contained ; as in the Floridee. Confluent : blending together. Conidia: non-sexual spores; often borne on aerial branches or hyphe. Coniferous : bearing cones. Conjugation : fusion of the contents of two cells to form a new cell or spore, as in some Algz; union of two cells equal in size and appearance. Connate: united, or grown together from the first. Connate-perfoliate leaves : opposite, with bases grown together through which the stem passes. Connective: the part of the filament between the two anthers. Connivent : coming in contact or converging. Contorted : twisted, same as convolute. Contracted: narrowed or shortened. ; Convolute: (in yernation) rolled up from one edge; (in zstivation) twisted, or with one edge of each petal overlapping that of the next. ; Copulation: union of swarm spores, etc.; fusion of two masses of protoplasm, Cordate : heart-shaped. Coriaceous : leathery. 5 Cork: a kind ‘of tissue with firm, dry cell-walls, destitute of cell- contents and impermeable to liquids and gases. 340 GLOSSARY. Cork cambium: phellogen, or meristematic cells which produce cork-cells. Corky: like cork; having cork. Corm: a solid bulb. Cormophyte: plants with stem, root, foliage, etc. Corolla: the inner set or whorl of the floral envelopes ; the petals taken collectively. Corona: a crown; the appendage at the top of the claw of some etals. Ghionake : having a corona or crown. Corpuscula : the elongated bodies in ovules of the Gymnosperms in which the germ-cells originate. Corrugate: wrinkled. Cortez: the rind; the part of the stem external to the wood or fibro-vascular bundles. Cortical: pertaining to the cortex, or rind. Corymb : a level-topped flower-cluster with centripetal inflorescence. Corymbose: in corymbs, or like corymbs. Costa : a rib. Costate: ribbed ; with ridges. Cotyledons : the seed-leaves, or first leaves of the embryo. Crateriform: goblet-shaped. Orenate: scalloped, or having rounded teeth. Crenulate: similar to crenate, but finer. Crested : with a crest-like appendage. Oribriform, or Cribrose: sieve-like. Cross-fertilization : the fertilization of the ovules with pollen from a different flower. Crown, Corona: the appendage at the top of the claw of some petals. Crueiferous, Cruciform, or Oruciate: having the form of a cross. Crustaceous: crust-like; hard and brittle. aa ep : s plant destitute of flowers and producing spores instead of seeds. eae destitute of flowers and producing spores instead of seeds. Crystalloids : crystal-like albuminous bodies in aleurone grains. Cucullate : hooded, or hood-shaped. Culm: the stem of Grasses and Sedges. Ouneate, or Cuneiform : wedge-shaped. Cupule: the cup of the acorn; a little cup. Cupuliferous : having a cupule. Cuspidate : having a sharp, stiff point. Cut: incised or cleft. Cuticle: same as cuticula. Cuticula: the thin continuous external layer of the epidermis-cells, Cutting : a severed portion of a plant used for bud-propagation. Cycle : circle; one turn of a helix or spire. me: a flower-cluster with centrifugal inflorescence. mose: having cymes, or like a cyme. GLOSSARY. 341 Cystolith: a projection of cellulose into the cell-cavity which is impregnated with calcic carbonate. Cytoblast : a name formerly used for the nucleus of the cell. Daughter-cells: the new or young cells arising from existing cells, Deca (as a prefix): ten; as decandrous, with ten stamens. Decandrous: having ten stamens. Deciduous: falling off early, as deciduous petals; falling off at the end of the season, as deciduous leaves. Decompound : several times compounded. Decumbent : lying on the ground, but the summit tending to rise. Decurrent : prolonged downwards on the stem. Decussate : in pairs which cross each other, or placed at right angles, Definite : of a fixed number, (in inflorescence) same as centrifugal. Dehiscence : opening ; mode of opening, as of anthers, etc, Dehiscent : opening regularly. Deliquescent: repeated branching till the trunk disappears in branches. Delioid: triangular. Demulcent : a bland mucilaginous substance which protects the tissue from irritation. Dentate: toothed ; with teeth pointing outwards, Denticulate : with small teeth. Depressed : as if flattened, from above. Dermatogen: the epidermis of the growing point. Determinate: fixed; definite. Di, or Dis (in Greek compounds) : two or double. Diadelphous : filaments united into two sets. Dialypetalous : same as choripetalous or polypetalous. Diandrous : having two stamens. Dichasium : a two-parted or two-rayed cyme. Dichlamydeous : having a calyx and corolla. Dichotomous: divided into two forks. Dichogamous, Dichogamy: maturity in a perfect flower of either the stamens or the pistils in advance of the other. Diclinous : when flowers are of separate sexes, Dicotyledon: an exogenous plant, or one whose embryo has two cotyledons. Dicotyledonous : having two cotyledons. Didynamous : having two pairs of stamens, with one pair shorter. Diffuse : much and irregularly spreading. Digitate leaf: one with the leaflets attached at « common point or end of the petiole. Dimorphism, Dimorphous: having two forms, as two sets of flowers, one with long stamens and short pistil, and the other with short stamens and long pistil. Dicecious : with staminate and pistillate flowers on different plants, Dipterous : winged. ; : ; Disciform : depressed and circular, like a disk or quoit. Discoid, or Discoidal ; without rays. 342 GLOSSARY. Disc, or Disk : an elevated rim of the torus. Dise-flowers: the florets of a Composite flower, which are on the receptacle and have no rays. Dissected : finely divided or cut. Dissepiment : partition of an ovary or fruit. Distichous: two-ranked ; in two rows. Distinct : not cohering ; not united with each other. Divaricate: extremely divergent. Divided leaf: one with the blade divided to the midrib. Dodecandrous : with twelve stamens. Dorsal suture: the outer suture, or that corresponding to the midrib. Double flower : one with the petals multiplied. Downy : having short and soft hairs. Drupe: astone fruit. —~ Duct: fused cells which form a continuous vessel or tube. Duramen: the heart-wood. Dwarf: diminutive. E, or Ex (as a prefix): destitute of. Eared : having ear-like appendages. Ebracteate : destitute of bracts. Ebraceteolate: without bractlets. Echinate : with prickles, Echinulate: with small prickles. Ectoplasm: the hyaline layer surrounding the naked protoplasm. dentate: toothless; not toothed. Efflorescence : anthesis; flowering. Elaters: the threads interspersed with spores of Liverworts, etc. Eleutheropetalous: petals free or distinct; polypetalous or chori- petalous. Elliptical : oblong with regularly rounded ends. Emarginate: with a notch at the summit. Embryo: the rudimentary plantlet in the seed. Embryo-sac: the enlarged cell of the ovule in which the embryo arises. Emersed : raised above water. Endocarp : the inner layer of a fruit. Endochrome: coloring matter in cells, especially that in Alge. Endogen: a plant with woody fibres (or bundles) and pith com- mingled ; a Dicotyledonous plant. Endogenous: arising or growing within; like an endogen. Endosperm : the albumen, or part of the seed which develops within the embryo-sac. Endospore: the inner wall of a spore. Ensiform : shaped like a sword. Entire: even; not notched nor toothed. Entomophilous flowers: those whose fertilization (pollination) is = effected by insects. Ephemeral : lasting but a day. Epi (as a prefix): upon, GLOSSARY. 343 Epicarp : the outer layer of a fruit. Epidermis : the outer Tapa of cells. Epigynous: situated upon the pistil or ovary. Epipetalous : upon the petals, Epiphyte : a plant growing on another, but not receiving its nourish- ment from it. Episepalous: upon the sepals. Equitant: astride. Erose: gnawed. Ergot: a horn-like sclerotium of the hyphe of the fungus Claviceps purpurea. Estivation : same as wstivation, Etiolated : blanched. Evergreen: not deciduous ; remaining green all winter. Ex (as a prefix): destitute of. Exalbuminous: with no endosperm or albumen external to the cotyledons. Excurrent: running out to the very top or beyond the apex; as the trunk of a tree, the midrib of a. leaf, ete. Exhalation: transpiration or evaporation through the stomates. Exo (as a prefix) : outwards. Exocarp: the outer layer of the pericarp. Exogen: a plant with pith, surrounded by a ring of wood or fibro- vascular bundles, and this by a bark or cortex; a Dicoty- ledonous plant. Exogenous: with the structure of an endogen; outside growing. Exospore: the outer wall of a spore. 7 eee that which promotes discharges from the throat and ungs. Exserted: protruding. Exstipulate: destitute of stipules. Extine: the outer layer of a pollen grain. Extrorse: directed or turned outwards. - Eye: the bud on a tuber. Faleate: shaped like a scythe. Family : a group of allied genera. Farina: starch. Furinaceous: like, or containing starch. Farinose: covered with a meal-like powder. Faseiate: banded ; abnormally flattened stems. Fasciation : a monstrosity in which the stem broadens and flattens. Fogeicled : in a bundle. Faveolate: same as alveolate; like a honey-comb. Feather-veined : pinnately veined ; veins branching from a midrib. Feathery: plumose ; beset with hairs along the sides. Ferruginous : like iron-rust in color. Fertile: pistillate ; producing. . ; Fertilization: the process which resulis in the formation of the embryo. 344 GLOSSARY. Fibre : an elongated cell, or fine filament. Fibril, Fibrilla: a very small fibre or thread. Fibrous: containing, or like fibres. Fibro-vaseular bundles: woody threads or bundles composed of ; fibrous, vascular, and parenchymous elements. Filament : as thread-like portion of the stamen which supports the anther. Filamentous: thread-like, or bearing slender threads, Filiform : thread-form. Fimbriate: fringed. Fission : division of any body into two parts by gradual constriction. Flabellate, Flabelliform: fan-shaped. Flagellum: a long whip-like filament or cilium. Fleshy : succulent, composed of pulp or flesh. Floating : swimming on the surface. Floceose : with tufts of woolly or long soft hairs, Floceulent : diminutive of floccose. Funiculus : the stem or stalk which supports the ovule in the ovary. Fuscous: grayish-brown. Fusiform : spindle-formed. Galeate: helmet-shaped. Gamo (as a prefix): united. Gamopetalous : petals united. Gamosepaleus : with sepals united. Gemme : a mass of cells forming a body similar in function to a bud. Gemmation : budding. Genera: plural of genus. Generic: relating or pertaining to genus. Genetic : by inheritance; genealogical. Genus : a group of allied species. Geotropism : turning towards the earth. Germ: a young bud; point of growth; that from which anything originates. Germination: sprouting ; sending out a filament; the development of the plantlet at the expense of the nourishment contained in the seed. Gibbous: swollen at one point. Glabrous : smooth; not hairy. Gland : a cell, or mass of cells which secretes something. Gleboids : round bodies similar in occurrence and behavior to the crystalloids. Globular - spherical, or nearly so. Globule : the male organ or antheridium of the Characez. Glossology: explanations of technical terms. Glumes: the husks or bracts which are inserted at the base of a spikelet. Glutinous: viscid ; sticky. Gonidia: the green bodies in the thallus of the Lichens, Grain: a caryopsis; the fruit of the Graminezx. GLOSSARY. 345 Gramineous: pertaining to grain or the Graminezx. Granulose : the most readily soluble constituent of a starch grain. Guard-cells: the two cells surrounding a stomate. Gymnos (as a prefix): naked. Gymnocarpous: with a disc-like, exposed hymenium, as in some Lichens, etc. Gomnosperm : a plant with naked seeds (not enclosed in an ovary). Gymnospermous : having naked seeds. Gynandrous : the stamens united with the pistil. Gynecium : the pistil or pistils of a flower taken collectively. Habit : the general appearance of the plant. Habitat: the place where a plant grows. Hackle: same as heckle. Hairs: outgrowths from cells; hair-like appendages. Hairy: having hairs. Hastate : with a spreading lobe on each side at the base. Haustoria : outgrowths from. hyphe, which penetrate the cells fox the purpose of obtaining nourishment. Heart-shaped : ovate with a sinus at base; cordate. Heart-wood: the mature wood of exogenous trees, generally more or less colored and destitute of sap. Heckle : As draw through teeth or a comb in order to separate the re. Heliotropism : turning towards the sun or light. Hepta (as a prefix): seven. Herb: a plant in which no woody tissue develops. Herbaceous: like an herb; of the texture of an herb. Herbarium, Herbal: a collection of dried plants. Hermaphrodite: having both stamens and pistils in the same flower. Heteros (as a prefix): diverse or various. Hex (as a prefix): six. Hilum: the scar of the seed, or point of its attachment in the ovary. Hirsute: having stiffish or beard-like hairs. " Hispid : having stiff hairs; brisily. Histology: that department of botany which treats of minute anatomy or of tissues. Hoary: grayish-white. Homologue: that which corresponds in structure. Homologous: of similar or corresponding structure. Hybrid: a cross-breed between two species. Hymenial layer : the spore-bearing layer of hyphz in Fungi. Hymenium: same as hymenial layer. Hyphe : the vegetative threads or filaments of Fungi. Hypo (as a prefix): under; beneath ; lower. : ; Hypoderm: thick-walled or otherwise peculiar cells immediately below the epidermis. Hypogynous : inserted under the pistil. . Hypocotyledonary : under or below the cotyledons in the embryo, as hypocotyledonary stem. 346 GLOSSARY. Imbricate: overlapping, like shingles or tile on a roof. Immersed: under water. Imperfect flower : one which is destitute of either stamens or pistils. Incised: cut; jagged; cut irregularly. Included: not protruding ; enclosed. Incomplete flower : with one or more of the four parts wanting. Indefinite: of no fixed number; (in inflorescence) centripetal or in the direction of the apex or top. Indchiscent : not opening of itself. Indeterminate: not definite, (in inflorescence) same as indefinite, Indigenous: native; not introduced. Induplicate: with edges folded in, or turned inwards. Indusium: the thin membrane sometimes covering the sori. Inferior : below; attached below. Inflated : swollen or bladdery. Inflexed : turned inwards. Inflorescence: arrangement of flowers on the stem ; flowering. ‘ Innate anther : one attached by its base to the apex of the filament. Inserted : attached. Insertion: mode or place of attachment. Anspissated: thickened by evaporation. Intercalary growth: that which takes place at an intermediate point and not at the apex. Intercellular spaces : spaces arising between cells. Internode: the portion of the stem between the nodes or joints. Intine : the inner coat or membrane of the pollen grain. Introrse : turned inwards or towards the axis. Intussusception : interstitial reception of particles. Involucel : a small or partial involucre. Involucrate : having an involucre. Involucre : a whorl of bracts or leaves below a flower or other part. Involute : rolled inwards, Irregular flower : one in which some of the members or any one or more sets of organs are unlike the others in shape or size. Keel : a projecting ridge ; the two anterior petals of a Papilionaceous ower. Key-fruit: samara, as the fruit of the Maple. Kingdom : the most comprehensive group in nature, as Vegetable Kingdom. Labellum : the odd (more or less modified) petal of an Orchid flower. Labiate : lip-shaped ; bilabiate. Lamella: a flat plate or thin layer; blade. Lamina: blade; a plate. Lanate (Lanose): woolly, or with soft entangled hairs. Lanceolate : shaped like a lance. Latent: not developed; dormant; concealed. Latex: the juice (usually milky or colored) in vessels of plants, Laticiferous: having latex. GLOSSARY. 347 Leaf-blade (Lamina) : the thin expanded portion of a leaf. Leaflet; one of the divisions or parts of a compound leaf. Leaf-scar: the scar on the stem after the leaf has fallen. Leaf-stalk (Petiole) : stem of the leaf. Legume: a simple ovary or pod which at maturity splits along both ventral and dorsal sutures. Leguminous : having legumes ; like a legume. Lenticel : an elevated portion or spot on Elder and other stems, con- sisting of a corky mass, which replaces the stomate. Liber ; the inner or fibrous bark of exogenous plants. Ligneous, or Lignose: woody. Ingue: the ray or strap-shaped covolla of some flowers of Com- posite; the appendage at the summit of the leaf-sheath in Grasses. Ligulate: strap or tongue-shaped. Liliaceous : like a Lily. Limb : the blade of a petal, border of a corolla, etc. Iinear : narrow and flat. Inp: the principal division, or lobe of a labiate corolla and calyx ; the labellum. Lobate: having lobes. Lobulute: diminutive of lobate. Loculicidal : splitting down the middle of the back of each cell or cavity. Loment: a pod which separates transversely into joints or parts. Lomentaceous : like a loment. Innate: crescent-shaped. Inrate : lyre-shaped. Lyrate leaf: a leaf with the terminal lobe large and roundish, and the lower lobes small. » (Greek m): in measurement one thousandth of a millimetre. Macro (as a prefix): large. Macrospore: the larger of two kinds of spores, as in some Lycopods. Maculate : spotted. Medullary : relating to the pith. Medullary Rays: the lines or portions of parenchymous tissue regularly interspersed in the wood, and radiating from the ith. Membranaceous, or Membranous: like a membrane; thin, and more or less translucent. . Mericarp: one of the closed half-fruits of the Umbelliferx. Meristem: generating tissue, or tissue capable of growth by cell- division. Meristematic: having or like meristem. Meros (in compound words) : parted. : Mesocarp: the middle one of three layers of the pericarp. Mesophyll : the parenchymous tissue forming the interior of the leaf- d blade. - : Mesophiem : the middle bark. 848 GLOSSARY. Metamorphosis : change ; a gradual change into something else. Metastasis : all the chemical changes after assimilation. Micropyle : the opening in the ovule by which the pollen-tube enters. Mierospore : the smaller of two kinds of spores; as in some Lycopods. Midrib: the large vein or rib in the middle of the leaf. Monadelphous stamens : those united by their filaments into one set. Moniliform: necklace-shaped ; contracted at intervals. Mono (as a prefix): one or (sometimes) united ; as monopetalous. Monoclinous : hermaphrodite. Monocotyledon : a plant having seed with but one cotyledon Monocotyledonous : having but one cotyledon. Monolocular : one-celled ; having one cavity. Monecious: having staminate and pistillate flowers on the same lant. Monopodial branching: the new branches are lateral, the original growing point of the stem not dividing, as in dichotomous branching. Monstrosity: a form which deviates greatly and abnormally from the usual. Mordant: a substance which unites firmly both with fabrics or organic fibres and with dyes, thus fixing the latter. Morphology: that which treats of forms especially in a comparative sense ; sometimes used in place of metamorphosis. Mother-cell: that cell which gives rise directly to new cells. Mucronate: with an abrupt sharp point. Multi (as a prefix): many. Muscology : the department of botany which treats of Mosses. Mycelium: the vegetative threads or filaments of Fungi. Mycology: that part of botany which treats of Fungi. Naked : wanting some usual covering. Napiform: shape of a turnip. Narcotic: (in small doses) relieving pain and causing sleep; (in large doses) producing stupor. Natural classification: that according to affinity, or that which is based on all the characters. Nectar: the honey or sweetish substance secreted by nectaries. Nectary: the tissue or organ usually in connection with the flower, which secretes a sweetish substance called nectar. Nectariferous : bearing nectar. Nerve: veins of leaves especially when parallel. Netted-veined : the veins anastomosing so as to form a net-work. Node, Joint : the place on a stem from which a leaf or pair of leaves springs. Nodose: knotty. Nomenclature: see binomial nomenclature. Normal: usual ; according to rule; typical. Nucleolus: the body within the nucleus of a cell. Nucleus : the body of the ovule; the small denser body in the proto- plasm of a cell. GLOSSARY. 349 Nucule : the female organ of Characes. Numerous : indefinite. Nut: a hard indehiscent, mostly one-seeded fruit. Ob (as a prefix): reversely. Obcompressed : flattened opposite to laterally. Obcordate: broadly notched at the apex. Oblanceolate: lance-shaped, but tapering downwards. Oblong : much longer than broad, the two ends rounded. Obovate: ovate, with the broad end upwards. Obtuse : blunt. Ochrea: the sheathing stipule as in Polygonum.: Ochreate : with ochrex or sheath-like stipules. Ochroleucous : yellowish-white. Octo (as a prefix): eight. Offcinal : having an approved use in medicine. Offset: branches at the ground which take root. Oligos (as a prefix): few; as oligandrous, few stamens. Oégonium: a large cell which is the female reproductive organ in the Odsporez. Odsphere : a rounded mass of protoplasm within the odgonium. Oéspore; the fertilized and ripened odsphere, having a cell-wall. Oésporee: the division of plants which are characterized by the production of an oégonium. Open bundles: those fibro-vascular bundles which contain cam- bium. Operculum : the lid of the capsule or theca of Mosses. Opposite : ay opposite sides of the stem, (of stamens) in front of etals, etc. Orbieadaes or Orbicular : in outline round, or nearly so. Orchidaceous : like an Orchid. Order : a group of allied genera. Organ: any part that has a special function to perform, Orthos (as a prefix): straight. Orthotropous ovule: erect; with the micropyle at the apex or opposite the chalaza. Oval: broadly elliptical. Ovary: the lower part of the pistil which contains the ovules. Ovate : egg-shape, with the broad end downwards ; as ovate leaf. Ovule: the body in the ovary which develops into the seed. Palet (Pale): a chaff or chaff-like bract, as in Composite flowers; that which corresponds to a sepal in the grass-flowers. Palmate leaf: with the leaflets attached at the top of the petiole and spreading like the out-stretched fingers of the hands. Panicle: an open cluster or compound raceme. Papilionaceous: more or less butterfly-shaped; the upper petal is called the Banner or Vexillum, the two side petals Ale, and the two anterior ones the Keel. Papilla : a minute elevation. 350 GLOSSARY. Puppus : the bristles, scales, teeth, or chaff crowning the achenium of many Composite. Parasite: a plant situated on another from which it draws its nourishment. Parasitic: drawing nourishment from another plant. Parenchyma: the soft tissue in the leaf; tissue whose cells are roundish, or if elongated not having pointed ends. Parenchymous: having or like parenchyma. Parictal : attached to or belonging to the wall. Parted : divided almost to the base or midrib, ete. Parthenogenesia: production of seed without the intervention of pollen. Pauci (as a prefix): few. Pectinate : finely divided, like the teeth of a comb. Pedate: like a bird’s foot. Pedicel: the branch of the peduncle which supports the flower. Pedicellate (or Pedicelled) : having a pedicel. Peduncle: the flower-stem or stalk supporting one or many flowers. Peltate : shield-shaped. Penta (as a prefix): five; as pentamerous, five-parted, ete. Pepo: the Gourd fruit, or fruit like the Melon or Cucumber. Perennial: persisting from year to year. Perfect flower : one with both stamens and pistils. Perfoliate leaf: with the base extending around the stem so that the latter appears to pass through the leaf. Pert (as a prefix): around. Perianth: the floral envelope, especially when the distinction between the calyx and corolla is not evident, as in Lilies. Periblem : the portion immediately under the dermatogen and which becomes the cortex. Pericarp : the wall of the ovary or fruit. Periderm: a continuous corky layer surrounding the stem. Peridium: an investing cellular layer or wall, as in case of the fruit of some Fungi, as Puff-balls, Cluster-cups, ete. Perigynous: situated on the calyx. Perisperm: the portion of reserve material of the seed which, in a few cases, is stored up outside of the embryo-sac. Peristome: the circle of teeth around the orifice of the capsule or theca of Mosses. Persistent: remaining longer than the usual time. Perithecium : the wall of the fruit or sporocarp of some ascomycetous Fungi. ; Petal: one of the parts or leaves of the corolla. Petiolate: having a petiole. Petiole: the stem or stalk of a leaf. i Pheenogam: a plant which produces flowers and seeds. Phenogamous : having flowers and producing seeds. Phellogen: cork-cambium ; meristem which produces cork-cells, Phenogam : same as pheenogam. Phloém : the bast portion of a fibro-vascular bundle. GLOSSARY. 351 Phycoerythrine: the red pigment in some Ales (Floridee). Phycology: that department of botany which treats of Algae. Phycoxanthine : the Tiowiih or yellowish coloring matter in Diatoms. Phyllotaxy: leaf arrangement. Phyllome: that which in general answers to a leaf. Pileate: having a pileus or cap. Pileus: the cap or sporocarp of Toad-stools (Agaricus). Pileorhiza: the root-cap. Pilose: having soft slender hairs. Pinna: a primary division of a pinnate, bipinnate leaf, etc. Pinnate-leaf: having the leaflets on two sides of a common petiole. Pinnatifid: pinnately-cleft. Pinnule : a division of a pinna. Pistil: the central organ of the flower in which (ovary) the seeds are produced. Pistillate: having pistils, but no stamens, Pith: the parenchymous tissue in the centre of an exogenous stem. Pitted: having pits, or depressions. Placenta: the line or part of the ovary to which the seeds are attached. Plasmodium: the naked protoplasm of the Slime Moulds (Myzo- mycetes). : Plerome: the central cylindrical mass directly behind the growing point and enclosed by the periblem. Pleurocarpous Moss: one whose fruit is borne laterally and not from the apex of the stem. Plicate (Platted): like the plaits of a fan. Plumose: feathery. Plumule: the bud terminating the caulicle in the embryo. Pod: a legume, or any kind of a capsule. Pollen: pollen-grains; the powdery fertilizing grains of the anther. Pollen-tube : the tube emitted by the pollen grain which grows down through the stigma and style. ; Pollination: the conveyance of the pollen from the anther to the stigma. Pollinia: Gamatinated pollen masses. Poly (as a prefix): many (or separate, as in polypetalous). Polygamous : some of the flowers perfect and some imperfect. Polypetalous: of separate (distinct) petals ; petals not united. Polysepalous: of separate (not united) sepals. Pome: a fleshy fruit; like the apple, pear, ete. Posterior: behind; (in axillary flowers) next to the axis of inflores- cence. Prefloration: sstivation. Prefoliation : vernation. Primine: the first or inner integument of the ovule. Primordial : first. Primordial cell: a naked or membraneless cell. Primordial epidermis: the first formed epidermis over the growing point. 852 GLOSSARY. Primordial leaves are those of the plumule. Primordial utricle: the thin protoplasmic sac lining the walls of cells which have very much cell-sap. Process: a projection. Pro-embryo : the filamentous or cellular mass which sometimes grows directly from the spore, and from which a plant directly or indirectly springs. Promycelium: a filamentous growth from some spores which bears sporidia. Prosenchyma: tissue with long and pointed cells. Prosenchymous: like or having prosenchyma. Protandrous: same as proterandrous. Proterandrous: said of flowers whose stamens precede the pistil in maturing. Proterandry: stamens maturing before the pistil. Proterogynous: having flowers whose pistils precede the stamens in maturity. : Proterogyny: ripening of the pistils before the stamens. Frothallium: the growth from the Fern-spore, and on which the organs of reproduction develop. Protista: those low organisms not clearly referable either to the group of animals or plants. Protogynous: same as proterogynous. Protonema: the filamentous growth from the Moss-spore from the buds of which the Moss-plants develop. Protophyta: the lowest division of plants. Protoplasm: the nitrogenous semi-fluid mass in cells. Protos (as a prefix): first; one; lowest. Pseudo (as a prefix): false; spurious. Pseudopodia: protrusions or branches from naked protoplasm. Pieridophyta : the division which includes the Ferns and their allies. Pieris: wing. Pubescent: hairy; especially having soft hairs. Punctate: having dots or apparent holes. Punctum vegetationis: the covered growing point of stem or root. Pungent: terminating in a rigid sharp point. Putamen: the shell of a nut; the endocarp of a stone fruit. Pyriform: pear-shaped. Quadra (as a prefix): four. Quaternary: consisting of four elements. Quinque (as a prefix): five; as quinquefoliate, five-leaved. Race: a marked “variety” or “form” perpetuated by seed. Raceme : a flower-cluster with an elongated axis bearing pedicelled flowers, centripetal in development. Racemose: like a receme, or in racemes. Rachis: the axis of a spike, of a compound leaf, and the like. Radiate: having rays. Radical: to or from the root, or from a root-like (subterranean) stem ; pertaining to the root. GLOSSARY. 353 Radicle: the lower part of the caulicle in the embryo which develops inte the root, Radiz: root. Ramose: branching. Raphe: the seed-stalk or funiculus when applied (adhering) to the ovude, as in an anatropous ovule. Raphides : needleshaped crystals in the cells. fay: a marginal flower, especially if ligulate, Receptacle : the enlarged end of an axis or peduncle which supports a head of flowers. Reflexed: bent backwards. Regular flower: the members in each wher] alike in shape and size. Rejuvenescence > one process of cell-formation, as by all of the proto- plasm in a cell contracting and itself becoming a new cell. Reniform: kidney-shaped. Repand: with a wavy margin. Repent: creeping. Resting spore: a zygospore. Reticwate: netted; as reticulate veins. Retrorse: directed downwards or backwards. Retting : the process ef preparing Flax, etc., by maceration or other- wise in order te effect a separation of the fibre from the stem. Retuse: with a shallow or obscure notch in a rounded apex. Reversion: petals changing back to sepals, stamens to petals; etc. Revolute: rolled backwards. Rhachis: the axis of a compound leaf, flower-cluster, etc. Rhaphe: the funiculus or seed-stalk when confluent with the side of an anatrepous ovule; raphe. Rhizoids: hairs which, as in Mosses, etc, perform the function of roots. Rhizome: root-stock; subterranean stem. Rib: a prominent vein in a leaf; a ridge Ribbed : having ribs. Ringent : gaping. Root: the descending axis of a plant, tipped with a root-cap, desti- tute of leayes, etc. Root-cap: the mags of cells at the tip of the root covering its grow- ing point. Root-hairs: the minute hairs or outgrowths from surface cells of the root. Rootlet : a little root, or branchlet of a root. Rootstock : rhizome; root-like stem or trunk on or under ground, Rosaceous: like a rose. Rostellate: with a small beak. Rostellum: a beak; the protuberance in Orchid-flowers in which the lower ends of the caudicles of the pollinia are enclosed. Rostrate: beaked. Rotate: wheel-shaped. Rotation of pees mass movement of protoplasm in cells, Bugose: paren 854 GLOSSARY. Runcinate: with eoarse teeth pointing backwards, Itunner > a slender, prostrate rooting branch. 7 Saccate > having a sac or purse-shaped cavity. Sagittate : shaped like an arrovw-head. Salver-form : with a border spreading at right angles to the tube. Samara: a wing fruit; as in Maple. Saprophyte : a plant feeding on decaying organic matter. Sap-wood : the younger wood, still containing sap. Sarcocarp: the soft or fleshy part of a stone fruit. Scabrous: rough or harsh. Scalariform : like the rounds of a ladder. Scale: a very much reduced and more or less rigid or membraneous leaf. Seandent: climbing. Scape : a peduncle coming from the ground ; as in acaulescent plants. Scarious: thin, dry, and membranous. Scion: a twig used for grafting. Sclerenchyma: tissue in which the cells have thickened and indu- rated walls. Selerotium > a compacted and hardened mass of hyphe. Scurf: minute scales. Scurfy, or Seurvy: baving scurf. Secundine : the second or inner coat of the ovule, Seed: the fully developed ovule containing the embryo. Seed-leaves : cotyledons; the leaf or leaves of the embryo. Segment: a division or lobe. Semi (as a prefix): half. Sepal : cone of the leaves or parts of a calyx. Sepaloid : like a sepal in texture, etc. Separated flowers: those having only stamens or only pistils. Septate : divided by partitions or septa. Septicidal : where the dehiscence is through the partitions or dissepi- ments. Septifragal - where the walls of the ovary or valves break away from the partitions. Septum: partition. Sericeous: silky. Serrate: with teeth pointing forwards or towards the apex. Sessile» attached directly to the stem or stalk ; without a foot-stalk. Seta: a slender bristle-like body; the supporting filament of the Moss-capsule, ete. Selaceous : like a seta; bristle-like. Setiform: in the form of a bristle or seta. Sheath: the base of leaves, etc., which invests the stem. Shrub: a small woody plant; smaller than a tree. Shrubby: woody ; like a shrub. Sieve-cells, or Steve-tubes: those having holes or sieve-like openings in their partitions. Silicle: the short pod or pouch of the Cress family (Crucifers). GLOSSARY. 355 Silique: like a silicle, but much longer. 7 meer y : the glittering plates (Medullary Rays) in exogenous wood. Simple: not compound ; of one piece or part. Sinuate: with deep waves. Sinus : a recess or space between two lobes or projections. Smooth : not hairy nor hispid. Sori: plural of sorus. Sorus: the fruit-dot or mass of sporangia in Ferns. i : having a spadix. iz: a fleshy spike. : a large bract which envelops a flower-cluster. : widened at the top like a spatula. : all the individuals of one kind, descended as such from common parents, . Spermogonium : cavity which contains the filaments that bear the spermatia. Spermatia : the spore-like bodies produced in the spermogonia. Spermatozoids : the protoplasmic bodies or cells developed within the antheridia. Spicate: like a spike. Spike: a flower-cluster similar to the raceme, but with sessile flowers. Spikelet: a secondary spike; the cluster of flowers in Grasses sur- rounded by glumes. Spine: thorn; an indurated leaf or branch. Spinose : having spines. ‘Sporangium: the organ in which spores develop. Spore: the body resulting from fructification in the flowerless or Cryptogamous plants; destitute of an embryo, but having a function similar to that of the seed. Spore-case : sporangium ; capsule containing the spores. Sporidia : secondary spores, or those produced on the pro-embryo, or what develops directly from the spore. Sporiferous.: bearing spores. Sporocarp: the reproductive as opposed to the vegetative part in Cryptogams. Sport: an individual deviating much from the type, but whose characters are not transmitted. Spur : a projecting, more or less horn-like, appendage. Spurred: like or having spurs. Squamate, Squamose: having or like scales. Stamen: the floral organ which produces (in the anther) the pollen. Staminate: having stamens. Staminodium : a sterile cr abortive stamen. Stellate: star-shaped. Stem: the ascending axis of the plant. Stemless ; acaulescent ; having no apparent stem. Sterigma: the slender stalk or support of the spores in some Fungi. Sterile: unfruitful. Sterile flower : one with stamens but no pistils. * 856 GLOSSARY. Stigma: the upper end of the pistil which receives the pollen. Stipe: stem of a Mushroom, ete. Stipel: a stipule of a leaflet. Stipulate : having stipules. Stipules : appendages on either side at the base of some petioles. Stolon: a trailing, rooting shoot. Stoloniferous: bearing stolons. Stoma (pl. Stomata), or Stomate: the orifice or breathing-pore in the epidermis of leaves, etc. Stone-fruit: a fleshy fruit with a hard or stony endocarp. Stratification : alternate denser and less dense layers in a thickened cell-wall. Streak: appearance of a mineral when scratched; the line made by marking with a mineral. Striate: having longitudinal grooves or furrows. Striation: layers at right angles to those of stratification. Strobile : a cone-like multiple fruit; as of the Hop and Pine. Style: the part of the pistil between the ovary and stigma. Stylospore: stalked, and apparently non-sexual, reproductive bodies or spores, as in some Fungi. Sub (as a prefix): nearly or under. Suberose: like cork. Submersed: growing under water.. ; Subulate: awl-shaped ; broad at the base and pointed at the apex. Sucker : a shoot of subterranean origin. Suffrutescent : slightly shrubby. Suffruticose : low and shrubby at base. Suleate: having deep longitudinal furrows. Superior : above. Suspensor : the elongated growth in the embryo-sac on the lower end of which the embryo is formed. Suture: the line of junction of two parts or two edges. Swarmspore: a motile, naked spore. Symmetrical flower : one in which the members of the different whorls are the same in number. Syncarp, Syncarpine: a multiple fruit. Syncarpous: composed of two or more united carpels. Syngenesious : stamens with anthers united into a tube, Tap-root: the primary root with a stout body. Taxology, Taxonomy : that which relates to classification and its rules. Tegmen: inner coat of a seed. Teleutospore : a thick-walled winter spore of some Fungi (Uredinee). Tendril: a filiform coiling body for assistance in climbing. Teratology: that which relates to unnatural forms or monstrosities. Terete: round. Terminal; at or belonging to the end or apex. Terminology: glossology ; technical nomenclature. Ternary: in threes; having three elements. Testa: the outer, more or less firm, seed-coat. GLOSSARY. 357 Tetra (as a prefix): four. Tetradynamous : having six stamens, two of which are shorter than the others. Tetraspores : non-sexual spores; as of the Floridex ; mostly in fours. Thalamus: the receptacle of a flower. Thallophyte : a Cryptogamous plant which has no differentiation of stem and leaves. Thallus : a cellular expansion without differentiation into caulome and phyllome. Theca: the sporangium or spore-case; as in Mosses, Throat: the opening in a Gamopetalous corolla, Tissue + any union of cells. Tomentose: with woolly hairs. Torus: the upper end of the peduncle which supports the floral organs. Tracheary tissue: ducts or vessels with thickened and variously perforated walls. Tracheides : cells with markings similar to the ducts. Transpiration: same as exhalation or evaporation. Tri (as a prefix): three or thrice. Triadelphous: the stamens united by their filaments into three sets. Tribe: a group under an order or family. Trichogyne: the filamentous prolongation of the carpogonium in some Cryptogams. Trichome : a hair. ‘ Trifoliate : a compound leaf with three leaflets. Triple-veined : with a large vein on each side of and approximately parallel with the midrib. Trisulcate: three-grooved. Truncate: as if cut square off. Tuber: an enlarged portion of a subterranean stem. Tunicate: coated. Umbel: a flower-cluster in which the pedicels have a common point of insertion. Unmbeliate: in or like umbels. Umbelliferous: bearing umbels. Undulate: wavy. Under-shrub : a very low shrub. Unguiculate: having a claw. Oni (as a prefix): one. : Unsymmetrical flower: one in which the number of parts in each set is dissimilar. Uredospore: a thin-walled “summer”? spore of the Uredo stage, formerly considered as a distinct genus; asin the Uredinee. Utricle: a seed like an achenium, but with a loose or inflated peri- carp. Vacuole: the cavity in the protoplasm of the cell filled with a watery fluid. . ; Valvate : having valves ; (in wstivation) edges meeting without over- lapping. 858 GLOSSARY. Valve: a lid; one of the pieces into which a pod, etc., splits. Variety : a group of individuals having some character in which they differ from the typical form of the species, Vascular : having or like vessels or ducts. Vasculum ; the botanist’s collecting-box. Vegetative cone: same as growing point. Punctum vegetationis. Vegetative point : same as growing point. Vein: a branch of the skeleton or frame-work of a leaf. Veinlet : a small vein. Venation: the veining or pattern of veining in a leaf. Ventral: on the side next the axis or centre; opposite of dorsal. Vernation: the arrangement of leaves in the bud. Versatile: attached at a point so as to allow swinging to and fro. Verticillate : whorled; in whorls. Vesicle: a little sac or bladder. Vesicular : bladdery. Vessel: duct. Vexillum : the upper petal or “banner” of a Papilionaceous corolla, Villose: having long soft hairs, Viscid : sticky; adhesive. Vitreous: glassy. Vitte: oil-tubes in the fruit of the Umbellifere. Viviparous : germinating or sprouting from seed or bud while yet on the parent plant. Voluble : twining. Volva: an external covering or veil; as in many Fungi. Water-pore: an orifice similar to a stomate, but with immovable guard-cells, filled with water. Whorled : verticillate ; in whorls. Wing: a thin expansion. Winged: with a wing or thin expansion. Woolly: with long entangled hairs. Xanthos (in compounds) : yellow. Aylem: the woody portion in the fibro-vascular bundle, Zone of life: the cambium in exogenous stems. Zodspore: naked motile cells (spores) in some Cryptogams. Zygospore : sexual spores with thick walls; as in the Conjugate, ete. Zygosporee : the division whose representatives produce “resting” spores or zygospores, “THE BEST TEXT-BOOK ON ENGLISH LITERATURE.” ENGLISH LITERATURE LITERARY CRITICISM. A Practicat Guipe ro Systematic Lirrrary Stupy. Witn Trricat Sevections, ILLusTRATIVE Criticisms, AND EXHAusTIve ANAL- YSES OF THE Best anp most Notas_e Works IN THE ENGLISH Lancuace. SHowimnc Wuat To Stupy, How to Stupy, anp How Best To Appty THE KNOWLEDGE Acquirgep THEREBY, By JAMES BALDWIN, A.M., Superintendent of Public Schools, Huntington, Indiana. English Prose... English Poetry. The citations from authors are made with taste and judgment; the critical and explanatory remarks are sound, without being wearisome ; and the quotations from the best critics and essayists are stimulating and suggestive. I shall take pleasure in commending it to students and others.—MeLvitte B, Anpexson, Professor of English Literature, Knox College, Galesburg, III. I think there are many points in which Baldwin’s English Literature is to be commended above any other work of like kind that 1 have examined. ° Its arrange- ment is unique and sensible. The list of books and studies suggested to the student at the close of each chapter is most excellent. The selections from the works con- sidered are well made, and calculated to awaken in the student a desire to read the whole. The work is a valuable addition to our list of school books,—Matitna C. Barns, Vice-Principal, and Teacher of Literature, Girls’ Normal School, Phila- delphia, Pa. This is the best text-book on poetry for general use, as well as for students, that we have ever read, for many reasons, which will be apparent to every one upon examination, and we hope that it will be generally introduced. The volume treating of prose, perhaps, better makes its commendabie features apparent. Its arrange- ment is excellent. This work is one of the best to meet popular needs, as it adopts several good ways of securing interest, and really gives an excellent general survey, which leaves the beginner firmly grounded, and evelops accurate literary taste.— The Globe, Boston, Mass. The system adopted by the author of this work has two features which distinguish it from other books on the subject, giving it a peculiar and genuine interest of its own. The first is its arrangement. The other is the free use of quotations from the best critics. Still another noticeable feature is that the illustrative selections are never trite. In short, Prof. Baldwin’s book has been put together with admir- able skill and judgment, is free from dullness, and an excellent work.—Good Literature, N.Y. JOHN E. POTTER & CoO., PUBLISHERS, PHILADELPHIA. (361) FRENCH SYNTAX. | A CRITICAL STUDY OF THE FRENCH LANGUAGE. By JAMES A. HARRISON, Professor of Modern Languages in Washington and Lee University, Author of a History of Spain, Greek Vignettes, etc. New Edition, WITH PRACTICAL EXERCISES PREPARED BY M. W. EASTON, Professor of Comparative Philology in the University of Pennsylvania. 12mo, Cloth. 677 Pages. Price $2.00. This is the most important book for a thorough Study of French which has yet been published in the English language. It is the work of an experienced teacher, whose scholarship and literary skill are of the highest order, done for the benefit of students and other teachers. In it every doubtful point which can arise in the study of the French language is considered and every difficulty is solved. The basis of the book is Edouard Matzuer’s cele- brated Franzésische Grammatik, supplemented by Dr. Carl Ploetz’s Syntax und Formenlehre der Neufranzé- sischen Sprache. To this a syllabus of Working Forms and an ample Historical Section have been added, and also a sketch of French Prosody and twelve appendices, which will be found of the greatest service. For the new edition, Prof. M. W. Easton of the Univer- sity of Pennsylvania, has prepared a series of seventy-five Practical Exercises, together with French-English and English-French Vocabularies—the object of which is to provide suitable material for the practice of translating into French. (362) “Tt seems to be beautifully done.” Pror. F. Bocuer, of Harvard. “So far as I am aware there has been nothing hitherto in English that filled anything like the same place. It should be in the hands of all teachers, and introduced into those classes to whose scale of study it is adapted.” Pror. Witiiam D. Warrney, of Yale. “T shall expect to derive great help from Prof. Harrison’s Syntax, and shall recommend it to my classes.” Pror. ALonzo WILLIAMS, of Brown. “T shall require the University booksellers to have the book on hand in numbers, and I shall strongly recommend all French students to get the book and study it carefully.” Pror. ScHELE DE VeERzE, University of Virginia. || From The Dial, Chicago. “Attention has already been called in these columns to Professor Harrison’s admirable “French Syntax’ (John E. Potter & Co.), A new edition now comes to us, adapted to the use even of beginners by the addition of a series of “Practical Exercises” from the competent hands of Prof. M. W. Easton, of the University of Pennsylvania. The essential rules and directions are printed with the exercises, to which full vocabularies are appended. After the exercises for beginners, a number of well-annotated and varied anecdotes, etc. for translation into French, provide for the needs of the more advanced student. No one should be misled by the too modest title to suppose this work to be merely an exhaustive syntax: the addition of full chapters upon phonology, etymology, historical grammar, and prosody, together with a great number of convenient tables and lists of various kinds, make the book a cyclopedia of exact information concerning the French language. All students will appreciate the advantage of having between the covers of one book answers to all the questions that it can ever occur to the most curious to ask. Teachers should be thankful that they can at last put into the hands of beginners the best French grammar in the world, and proud that they owe this privilege to an American scholar.” JOHN E. POTTER & CO., PUBLISHERS, PHILADELPHIA. (368) CHOICH THEXT-BOOKS. THE SCIENCE AND ART OF ELOCUTION; oR, HOW TO READ AND SPEAK. A Series of Exercises for Gesture, Calisthenics, and the Cultivation of the Voice; and a Collection of nearly One Hundred and Fifty Literary Gems for Reading and Speaking. New anp ENLARGED Eprrion. By Frank H. FEnno, of the National School of Oratory. 12mo, Cloth, Extra. Price $1.25. This work is designed to furnish both a theoretical and practical knowledge of elocution and oratory. The principles of .gvod reading and speaking have been carefully and minutely investigated by the author, and are presented in a simple and concise form, within the comprehension of the ordinary student, so that, with proper study and diligent practice, the art of good reading and good speaking may be thoroughly acquired. lor convenience of study, the work has been divided into four parts: THzorgericaL, VocaL CuLture, HEups ro THE Stupy, and READINGS and Recirats. I do not hesitate to give my unrestricted commendation of ‘‘ Fenno’s Science and Art of Elocution.”’ I consider it the best work of the kind published—well adapted to the common school, academy, and college, and this I say after a thorough test of its merits in our classes,—Pror. J. W. Rust, President of Bethel Female College, Hopkinsville, Ky. m It seems te mea very valuable book both for students and for teachers of advanced Elocution,—ELLen Bisyop, Teacher of Elocution, Normal School, Albany, N. Y. THE ARTIST AND HIS MISSION. A Study in Asthetics. Designed for the use of Schools and Colleges. By Rev. Wrursam M. Retiy, Pu.D., Professor of Ancient Languages, Palatinate College. 12mo, Cloth, Extra. Price, $1.50. A thoughtful contribution to the literature of zsthetics is ‘‘ The Artist and his Mission,” by Professor William M. Reily, of Palatinate College. It is written with the utmost modesty, and makes no pretence to original investigation; but it represents, in point of fact, no small amount of reading and reflection. The author’s views on the true object and purpose of art are clear and true, and are faithful to the conception of duty. Moral bean as well as physical is recognized in this treatise, which is creditable both to the learning and the spirit of its author. —Good Literature. EASY LESSONS IN GERMAN. A Manual of the Language, especially adapted for Beginners. By Avaustin Kwnoriacu, Teacher of Languages. 12mo, Cloth, Extra. Price, $1.00. The order of arrangement is logical, and agrees with that followed by English grammars. The book carefully gives only those rules and classifications that are of practical value, and calculated to aid the student in the early portion of his German course. JOHN E. POTTER & CO,, PUBLISHERS, PHILADELPHIA, (364) 3065. [One-third actual size.] THE ABOVE CUT REPRESENTS THE AMATEUR MICROSCOPE. SOLD BY JAMES W. QUEEN & CO., 924 CHESTNUT STREET. PHILADELPHIA. Price with one (No. 2) eye-piece, and one one-half inch objective (this is divisible, giving powers of 50 and 110 diameters), in walnut case with handle and lock, $23.00. The same as above, with the addition of a one-sixth objective, giving a range of powers up to 360 diameters, $28.00. 4am List of our ten catalogues will be sent by mail upon application. (365) No. 342. One-half actual size THE SCHOLARS’ MICROSCOPE. MADE BY Rm. & JT. BECE, 1016 CHESTNUT STREET. PHILADELPHIA. Price with one (No. 2) Eye-piece, and dividing Objective of one inch and one- quarter inch, giving powers from 40 to 285 diameters, in handsome Mahogany case, $25.00. This instrument has Draw-tube, extending to ten inches ; coarse and fine adjustments of focus, and Diaphragm. ‘The Mirror swings above the stage for the illumination of opaque objects. Illustrated Price Lists mailed /vee to any address.