RICHARD G. MILLER (^^^ 0(jy/u^c^*^/^tyt^^^^^^^ PLANTS AND THEIR USES AN INTRODUCTION TO BOTANY BY FREDERICK LEROY SARGENT FORMERLY INSTRUCTOR IN BOTANY IN THE UNIVERSITY OF WISCONSIN AND ASSISTANT IN THE BOTANICAL MUSEUM OF HARVARD UNIVERSITY So. WITH NUMEROUS ILLUSTRATIONS NEW YORK HENRY HOLT AND COMPANY COPYRIOHT, 1913, BY HENRY HOLT AND COMPANY PREFACE The main purpose of the book is to show some of the edu- cational possibiUties offered by plants of every day use, and at the same time to guide beginners to such general ideas about plants as should form part of a liberal education. There are a number of plants that every one ought to know because of their intimate connection with human welfare. These plants represent all parts of the vegetable kingdom, they are the very ones about which most persons have the greatest desire to learn, and they are mainly the ones which were first studied by mankind. Help the be- ginner, therefore, to learn at the outset as much about these economic plants as he is ready for; then help him to classify them scientifically, and he will be prepared to appreciate that wider view of the life of plants which inspires botany toda}'. On this plan I have tried to write such a book as I believe would have been most useful to me when I was a beginner. Botany taught by the historical method, as this procedure may be called, not only appeals from the start to the strongest practical incentives, but profits by the student's knowledge in many other departments, which knowledge it often en- riches. Thus pursued botany also offers an exceptionall}'' fine opportunit}^ for cultivating scientific habits of mind and methods of work. These are sure to economize energy in every intellectual undertaking. The scientific attitude and scientific ways of proceeding control modern progress, and in no better way can one catch the spirit of these than by the scientific study of plants. So closely similar are the needs of all who wish to make a good beginning that it becomes possible for a book like the present to serve many diverse classes of students. The iv PREFACE scheme is so elastic that no two classes need follow it in pre- cisely the same way; but may vary the work within wide limits, emphasizing now this aspect, now that, hurrying over one part and dwelling upon another as circumstances shall determine. The text printed in small type may be omitted with younger classes, or with those requiring only a short course. The matter in larger type will then be found to proceed connectedly, and to be in no way harmed by the omissions made. If a still shorter course be desired the class may go through as many topics as there is time for, leaving the rest to be taken up if possible at some future time. What- ever ground has been gone over, if well studied, will then be so much to the good; and since the educationally more im- portant subjects have been treated in the earlier chapters, the student may feel that even a little is worth while. The figures used in this book are mostly copies from various well-known works as indicated by the authors' names in parenthesis under the figures; the remainder are from original drawings by the writer. Permission has been very kindly granted by Dr. N. L. Britton and Judge Addison Brown to use the figures from their Illustrated Flora. In conclusion, I wish to acknowledge most gratefully the helpful criticisms and suggestions received from teachers and other friends during the progress of the work. Especial thanks are due to Charles W. Swan, M. D., for suggestions regarding medicinal and poisonous plants; to ]\Ir. Henr}" J. Williams, Mr. George W. Rolfe and Professor Kenneth L. Mark for help on chemical matters; to Professor G. H. Parker for reading evolutionary parts; to Mr. A. B. Seymour for reading the chapters on cryptogams; and to the botanists of the Harvard Herbarium and University Museum for facilitating my work with books and specimens. F. L. S. Cambridge, Massachusetts December, 1912 CONTENTS PAGE Preface iii CHAPTER I THE STUDY OF PLANTS 1. Botanical questions 1 2. The beginnings of botanj- 1 3. Our dependence upon plants 1 4. Human needs and the needs of plants 2 5. How plants are named 2 6. Early plant names 3 7. Binomial nomenclature 4 8. Species 4 9. Varieties 5 10. The genus 6 11. The authority 7 12. Plant families and higher groups 7 13. The departments of botanj' 8 CHAPTER II CEREALS 14. What cereals are 11 15. Characteristics of cereals 11 16. Importance of grains in ancient times 17 17. Earliest use of grains 20 18. Oats 25 19. Barley 25 20. Rye 25 21. Maize 25 22. Rice 25 23. Wheat 28 24. Buckwheat 29 25. The value of cereals 30 26. Water in grains 30 27. Ash 30 28. Nutrients 31 29. Carbohydrates 31 30. Proteids 33 31. Fats 34 V vi CONTENTS CHAPTER III VARIOUS FOOD-PLANTS PAOE 32. Classes of food-plants 35 33. Nuts 35 34. Pulse 40 35. Earth-vegetables 41 36. Herbage-vegetables 53 37. Fruit-vegetables 85 38. Fruits 88 39. Miscellaneous food-products 91 40. Vegetable foods in general 113 41. Food as fuel and building material 114 42. Measures of energy 115 43. Energv of vegetable foods 116 44. Rations 117 45. Food-plants in general 122 46. The primitive centres of agriculture 122 47. Relation between culture-period and native home 123 48. The multiplication of varieties 126 49. How varieties arise 126 50. Artificial selection 127 CHAPTER IV FLAVORING AND BEVERAGE PLANTS 51. Food-adjuncts 128 52. Spices 128 53. Savory herbs 137 54. Savory seeds 137 55. Miscellaneous condiments 137 56. Essences 146 57. Non-alcoholic beverages 150 58. Alcoholic beverages and stimulants in general 156 CHAPTER V MEDICINAL AND POISONOUS PLANTS 59. Medicines and poisons 162 60. Non-poisonous drugs 163 61. Poisonous drugs 176 62. Plants poisonous to eat 192 63. Plants poisonous to handle . 217 64. Poisonous plants in general 219 CHAPTER VI INDUSTRIAL PLANTS 65. U.ses of industrial plants 222 66. Fibers in general 222 CONTENTS vii PAGE 07. Surface fibers 225 68. Bast fibers 228 t)9. Mixed fibers 231 70. Pseudo-fibers 239 71. Woody fibers 240 72. Wood in general 241 73. True woods 256 74. Pseudo-woods 272 75. Cork. 279 76. Elastic gums 280 77. Resins 287 78. Coloring matters 290 79. Oils. . . ^. 295 80. Fuel 297 81. Useful and harmful plants in general 302 CHAPTER VII CLASSIFICATION AND DESCRIPTION 82. Systematic classification 305 83. Early attempts at classifying 306 84. Artificial systems 307 85. The Linna^an system 308 86. The natural system 310 87. Technical description 312 88. Early attempts at describing 312 89. The Linna^an reform in terminology 313 90. Terminology and nomenclature 314 CHAPTER VIII THE PARTS OF A SEED-PLANT 91. Flax as a t>T»e 316 92. The seed _ 316 93. The seedling and its development 317 94. The flower and the fruit 319 95. Physiological division of labor 319 96. Organs and their functions 321 97. Morphological differentiation 322 98. Morphological units .323 99. Members of the plant bodv 323 100. Homologies 326 CHAPTER IX THE CROWFOOT FAMILY 101. General features 328 .102. The vegetative organs compared 330 viii CONTENTS PAGE 103. The reproductive system 343 104. Plant formulas 352 105. The family chain 355 CHAPTER X VARIOUS PLANT GROUPS 106. The Magnolia Family (MagnoliaceaO 358 107. The Laurel Family (Lauracese) 360 108. The Crowfoot Order (Ranunculales or Ranales) 361 109. The Poppy Family (Papaveracea^) 361 110. The Mustard Family (Crucifera;) 362 111. The Poppy Order (Papaverales or Rhoeadales) 363 112. The Rose Family (Rosacea?) 363 113. The Pul.se P'amily (Leguminosae) 365 114. The Rcse Order "(Rosales) 367 115. The Linden P'amily (Tiliaceaj) 367 116. The Mallow Family (Malvaceae) 369 117. The Mallow Order (Malvales) 370 118. The Parsley Family (Umbelliferff) 370 119. The Parsley Order (Umbellales or Umbellifiora?) 371 120. The Buckwheat Family (Polygonaces?) 372 121. The Buckwheat Order'(Polygonales) 372 122. The Birch Family (Betulaces) 373 123. The Beech Family (Fagacea;) 374 124. The Beech Order (Fagales) 376 125. The Walnut Family ( Juglandacea;) 376 126. The Walnut Order (Juglandales). 376 127. The Willow Family (Salicacea-) 377 128. The Willow Order (Salicales) 377 129. The Crowfoot Series (Archichlamydeaj) 377 130. The Heath Family (Ericacea;) 378 131. The Heath Order (Ericales) 379 132. The Morning-glory Family (Conyolyulacese) 379 133. The Nightshade Family (Solanaceie) 382 134. The Figwort Family (Scrophulariacea;) 382 135. The Mint Family (Labiatse) 383 136. The Phlox Order (Polemoniales or Tubiflora;) 383 137. The Gourd Family (Cucurbitaceaj) 383 138. The Beimower Family (Campanulacea^) 384 139. The Sunflower Family (Composita>) 385 140. The Bellflower Order' (Campanulales) 386 141. The Beimower Series (Metachlanydea^j 386 142. The Dicotyl Subclass (Dicotyledones) 386 143. The Grass Family (GramineaO 387 144. The Grass Order (Graminales or Glumiflorai) 388 145. The Palm Family (Palmacea;) 388 140. The Palm Order (Palmales or Principes) 389 147. The Arum Family (Aracea;) 389 148. The Arum Order (Arales or Spathiflora;) 389 149. The Rush Family (Juncacese) 390 CONTENTS ix PAGE 150. The Lily Family (Liliaceae) 390 151. The Iris Family (Iridacea;) 390 152. The Lily Order (Lihales or LiliifloraO 390 153. The Orchid Family (Orchidacese) 391 154. The Orchid Order (Orchidales or Microsperma?) 391 155. The Monocotyl Subclass (Monocotyledones) 391 156. The Case-Seed Class (Angiosperma^) 391 157. The Pine Family (Pimicete) 392 158. The Yew Family (Taxaceie) 392 159. The Pine Order (Coniferales or Conifera?) 393 160. The Naked-Seed Class (Gymnosperma;) 393 161. The Seed-Plant Division (Spermatophyta) 393 162. The Vegetable Kingdom (Vegetabilia) 394 CHAPTER XI KINSHIP AND ADAPTATION 163. The problem of origins 428 164. The doctrine of special creation 429 165. The doctrine of organic evolution 431 166. Acquired adaptations 441 167. Selected adaptations 446 168. Acquirement versus Selection 452 169. Sudden adaptations 457 170. Evolution by choice 461 171. Evolution in general 464 CHAPTER XII LIFE-HISTORIES 172. Cycles of life 470 173. The Blue Algaj (Class Cyanophycea^) 470 174. The Green Algse (Class Chlorophycea>) 476 175. The Brown Algaj (Class Phieophycea;) 485 176. The Red Alga; (Class Rhodophycea;) 487 177. The Seaweed Subdivision, Alga; in genei'al 491 178. The Fission Fungi (Class Schizomycetes) 492 179. The Yeast Fungi (Class Saccharomycetes) 495 ISO. The Pin-mold Fungi (Class Zygomycetes) 495 181. The Water-mold Fungi (Class Oomycetes) 499 182. The Spore-sac Fungi (Class Ascomycetes) 499 183. The Spore-base Fungi (Class Basidiomycetes) 501 184. The Mushroom Subdivision, Fungi in general 503 185. The Spore-sac Lichens (Class Ascolichenes) 504 186. The Spore-base Lichens (Class Basidiolichenes). 508 187. The Lichen Subdivision, Lichens in general 508 188. The Thallophvte Division, Lobeworts (Thallophyta) 509 189. The Liverworts (Class Hepatics) 513 190. The True Mosses (Class Musci) 519 X CONTENTS PAGE 191. Th(> Bryophyte Division, Mossworts (Bryophyta) 530 192. 'Die Ferns (Class Filicinca,') 532 193. The Soouring-rushes (Class EquisetinaO 542 194. The Club-mosses (Class Lycopodina?) 544 195. The Pteridophyte Division, Fernworts (Pteridophyta) 548 196. Cryptogams and Phenogams 550 CHAPTER XIII THE PLANT'S PLACE IN NATURE 197. The three kingdoms 561 19 ovary, containing a small egg- shaped bod3% the ovule; (2) a pair of elongated middle parts, the stijles, each connecting the ovary with (3j a free, terminal part, the stigma, which is here like a little plume. Around the pistil are three stamens very like what are commonly met with in other flowers. Each stamen consists of (1) a double sac, the anther, in which are produced innum- erable dust-like particles, the pollen, and (2) a threadlike part, the filament, on the upper end of which the anther is borne. When the anther is ripe it sheds its pollen, a particle of which com- ing to rest upon an oat stigma tarings al)0ut the ripening of the ovule into a seed. As the ovule ripens, the ovary enlarges to keep pace with it, forming at last for the seed a firm protective cover- ing which together with tire seed constitutes the grain. Mean- while the styles, stigmas, and stamens, having fulfilled their office, Avither and fall off. The ripened ovary and its contents together with whatever parts ripen in connection with it (in this case two husks) constitute the fruit. Since the purpose of the flower is to form seeds, and this is ac- complished by means of stamens and pistils, these are called the CHARACTERISTICS 13 essential organs of a flower, A flower which has both is said to be perfect; if either alone, imperfect; or if with neither, rudimentary. While the floral parts of the oat are being formed they are protected by papery husks called bracts, a bract being or- FiG. 2. — Oat. A, Upper part of flower-cluster. B, a single spikelet in flower, with bracts spread somewhat apart. C, one of the outer bracts. D, an inner bract bearing an awn. /, pistil. G, lodicules. A and B about natural size, C, D, and /, enlarged. (Nees.) dinarily a small leaf-like organ belonging to a flower-cluster. A little cluster of grass-flowers together with their bracts, is called a spikelet. At the base of the inner bracts are the so-called lodicules which by swelling spread apart the bracts so as to expose the anthers and stigmas at the proper time for shedding or receiving the pollen. An aivn is a bristle- Hke appendage such as make up the "beard" of many grasses. 14 CEREALS FiQ. 3. — Oat. A spikelet (similar to B, Fig. 2) cut lengthwise to show the inner parts. Enlarged and somewhat diagrammatic. Sk, stalklot; R, R', its continuation as a little rachis within the spikelet; C, C, outer bracts; M, F, mature flower; Y, F, young flower not yet opened; R, F, rudimentary flower or pair of bracts with neither stamens nor pistils within; D, bract with awn (B); E, inner bract; G, lodicule; F, F', fila- ments bearing ripe anthers (R.^, RA') from one of which pollen (P) is falling; So, stigma; Sy, style; Ov, ovary, containing an ovule (Ol); YA, a young anther; YA', a similar one cut lengthwise to show the pollen forming within. (Original.) Fig. 4. — Oat spikelet in fruit. F, the awned inner bract swollen with the ripe kernel which it enwraps; A, awn; F', another ripe "oat" separated from the little rachis (R) and turned to show its inner face where the edges of the bract enclosing the kernel arc seen not ciuitc meeting at the center. About twice natural size. (Original.) A continuation of the stalk into a flower-cluster is called its rachis. Every one should be able to tell at sight such important plants as the six principal cereals. When in flower they may be distinguished by the peculiarities mentioned in the following synopsis taken in connection with the figures. CEREALS ?: fQ c. a o rn J o < X. w W - U T o a; rt CL, ^ 01 CJ w ffi c-c H c -^ oSTJ •3 "-I O c3 c3 :^J ^ ^ o > J > .c_j- o bSi - ^ ^ a 5 '^ '^ — H _2« ■=■ ? s ^ c *^ ^-C o 5 is W & ^ o = S c3 5^ O . Hi 11 Sis x O !C rt fe 16 CEREALS Fig. o. — Rice (Oryza sativn, Grass Family, Graminece). P, upper part of rice plant, one-quarter natural size; S, a spikelet from the same; L, rain-fJiuard or ligule at base of leaf-blade, inner view; natural size. (Martius.) CEREALS 17 16. Importance of grains in ancient times. Many facts go to show that cereals must have l)een among the very first plants raised from seed. The Roman ceremonies, before referred to, were patterned after religious rites which had Fir,. 6. — Rice. A, part of a flower-fluster of beardless rice, natural size. B, a spikelet of the same. F, a flower showing its six stamens, single pistil (with two styles and stigmas) and two lodicules. K, a ripe kernel. B, F, and K enlarged. (Nees.) been practised for centuries by the Greeks, among whom wheat and barley were greatly prized. Passages in the Hebrew Scriptures show that these were the grains cultivated throughout Palestine and in the valley of the Nile; and it is an interesting fact that a grain of wheat has been found 18 CEREALS Fig. 7. — Rye {Scmle ccrrale. Grass Family, Gramhirw). A plant, a flower- cluster, two spikelets with bracts spread apart, a flower, and a kernel. (Baillon.) CEREALS 19 embedded in a sun-dried brick from one of the Egyptian Pyramids lielieved to l)e over five thousand years old. Cer- tain prehistoric remains of the Lake Dwellers in Switzerland Fig. 8. — Wheat {Triticum tiativinn. Grass Family, Graminccc). X plant and flower-cluster of bearded wheat, a flower-cluster of beardless or "club" wheat, a piece of the zig-zag rachis, a spikelet, a flower, and a kernel. (Baillon.) show that wheat, barley, oats, and rye were in use among the ruder peoples of Europe, centuries before the Christian Era. The Chinese have record of the cultivation of rice in their country more than four thousand years ago. Until recent 20 CEREALS times they observed annually a very ancient custom in which rice grains were planted by the Emperor with appropriate ceremonies in token of its great value to the nation. Finally, in the New World, evidences abound of the cultivation of maize ages before the coming of Columbus. Ears of Indian corn occur along with the most ancient remains in Mexico and Peru. Moreover, the Spanish conquerors found that in Mexico the natives worshiped an agricultural divinity to Fig. 9. — Wheat. A, spikelot of beardless wheat, enlarged. F, flower with bracts spread. C, D, E, bracts. G, pistil with stamens, and a pair of lodicules at base. K^, lO, kernel. R, rachis. (Baillon.) Avhom they brought the first-fruits of their maize-harvest, just as the Romans brought their offerings of grain to Ceres. 17. Earliest use of grains. Although we maj' be sure that the cultivation of the grains began many years before the time of our earliest records concerning them, Ave have no means of knowing how long ago they were first i:)lantod as a crop; nor have we any definite knowledge of how any one of them first came to be cultivated. Still there is good reason to suppose that before the advantages of planting were discovered, it was the custom to gather the wild grain when it was ripe, just as certain savage tribes do Avith other grains at the present day. Thus it Avould happen naturally CEREALS 21 Fig. 10. — Common barley {Hordcum mlirum, var. vidgarc. Grass Family, Graminece) . Plant, flower-cluster, spikelet, flower, and fruit. (Baillon.) 22 CEREALS Fig. 12. — Six-rowed barley (//. sati- vum, var. hfixasticfwn). B3, a group of three spikelets. as they appear together at a joint of the rachis. B, Bl, single spikelets. F, a flower (one stigma partly re- moved) . Kl , A'-.', baek and front views of kernel. All more or less enlarged. (Nees.) Fig. 11. — Two-rowed barley (H. sativum, var. distichon). Flower-clustei and base of a spikelet, slightly reduced. (Hackel.) CEREALS 23 Fig. 14. — Maize. A spikclet from the tassel cut lengthwise to show its two flowers; the one on the right fully open, the other not yet mature. Sk, stalklet; C, C, outer bracts; D, E, inner bracts of the open flower; G, lodicules, which by swelling have spread apart the bracts; F', F", filaments cut across; F, filament bearing ripe anther (R, A) shedding pollen (P) ; Y, A, young anthers, the left hand one cut to show the pollen. Enlarged. (Original.) Fig. 1.3. — Maize {Zea Mays, Grass Family, Graminaw). A plant in flower. T, the "tassel" (a cluster of flowers having .stamens but no pistils); S, stalk; L, leaf; E, E, E, the "ears" (clusters of flowers hav- ing pistils but no stamens) ; N, N, nodes (swollen joints of the stem) ; B, B, brace roots, which serve as guys helping to hold the stalk up- right; R, earth roots; G, G, .surface of ground. About one-twelfth natural size. (Original.) 24 CEREALS Fig. 15. — Maize. I. A young ear cut thruugh the middle longthwiso. Sk, Sk, the main stalk; Sk', a short branch which bears the ear; Sh, sheathing lower part of the leaf which enfolds the whole ear and its husks; B, blade of the same leaf; R. G, the rain-guard which keeps rain from running into the sheath and iironioting tlecay; H, the "husks" or larg(>, more or less leaf-like l)ract.s around the ear; Sg, stigmas Cthe "silk") protruding beyond the husks, .\bout one-third natural size. II. A spikelet of the same ear, showing the bracts (C, C, D, D', E, E') and the ovary (O), and the lower part at holds the first place anions vegetable foods. Fig. 20. — Map showing, as in Fig. Ifi, native home and present range of rice. (Original.) Fkj. 21. — Map showing, as in Fig. 16, native home and present rang(> of maize. (Original.) Now that railways and steamboats have made transporta- tion easy, more and iikh-c wheat is being used ; for whenever it is equally available it is usually preferred as a breadstuff BUC'KWHEAT 29 to any other grain. Although nnich wheat of fine quahty is raised abroad, especially in Russia, France, and Austria- Hungary, our country produces more than any other. Fig. 22. — Buckwheat (Fagopyrum e^culentum, Buckwheat Family, Poly- gonacece). A, upper part of plant, showing leaves and flower-clusters; natural size. B, a flower enlarged, showing the following parts: — in the center a single pistil on the ovary of which are borne three styles ending in rounded stigmas; around the pistil eight stamens in two rows, the inner row of three; lietwrcn the rows of stamens at their bases, eight small itrotuberances (inxtar-glands) which secrete a sweet liquid {nectar) from which bees make honey; outside of the other parts of the flower come a circle of five more or less leaf-like organs — the sepals — together constituting the "flower-cup" or calyx which in this case is white or whitish. C, the same showing the arrangement of its parts as they appear when the flower is halved vrtically. D, stamens. E, the pistil enlarged. H, fruit, enlarged. F, the same cut lengthwise. ,/, the same, cut across, showing the flat curved embryo or rudimentary plantlet surrounded by seed food. G, embr\o removed from the seed and viewed from the side. (Baillon.'i — The plant grows lu.xuriantly in fields to a height of 0.5-1. m. It is smooth throughout. Bees which come for nectar transfer the pollen from flower to flower and so enable the plant to set good seed. 24. Buckwheat is sometimes included among cereals because it is cultivated for its grain. As will be seen, how- ever, from Fig. 22 this plant differs very much from the 30 CEREALS other cereals. It is a native of northern Asia where doul)t- less it has been cultivated for a long time; yet its introduc- tion into other regions was comparatively recent. Like rye its chief merit is that it will yield a profitable crop on very poor soil. The flour made from it, however, is correspond- ingly poor in nutritive value. It is usually mixed with other sorts of flour to which it imparts an agreeable flavor. 25. The value of cereals. Why is it that the cereal grains have been valued so highly from the earliest times? What makes them so much better than other vegetable foods, and why are some of them superior to others? The fact that these plants ripen their seeds within a few months after planting, and under favorable conditions yield such a large return for the labor bestowed upon them, will doubtless partly account for the high favor in which they are held; but as much the same may be said of other vegetaliles of far less value as food, there must be some more important reasons. In order to understand these, we must know some- thing of the chemical composition of cereals; that is to sa,y, we must learn what substances are to be found in the differ- ent grains and in what amount. 26. Water in grains. Every part of a ]:)lant contains or- dinarily a certain quantity of umter — succulent herbage and fruits like the watermelon having a great deal, while woody parts, seeds, and grains have comparatively little. The quantity of water contained in a given specimen, is esti- mated by drying a known weight of the material at the tem- perature of boiling water, and then rewoighing to find how much has been lost: the loss will be practically equivalent to the weight of water originally present. In the Food Chart on page 114 the student will find indicated the average percent- age of moisture in each of the cereals and in various other vegetable foods as commonly found in the markets. A glance will show what a comparatively small amount the cereals contain. For this reason they keep remarkably well when stored, and take up very little room in proportion to the amount of nutriment they afford. 27. Ash. If the sample dried as suggested be burned until all of the combustible material is consumed, there will CAKBOHYDRATES 31 remain a small quantity of ash or mineral matter, varying somewhat in the different kinds of cereals as shown in the chart. Upon further analysis this ash is found to consist of certain earthy substances (potash, lime, magnesia, soda, and silica) variously combined with phosphorus, sulphur, and oxygen. It is important to remember that such substances form the principal constituents of bones and teeth, and that cereals are particularly rich in the mineral matters specially reciuired for building these hard parts of our bodies. 28. Nutrients, A large part of the grain consumed in burning, consists of nutrients, i. e., nutritious substances, which form the main bulk. Besides this there is a small amount of woody material (non-nutrient) contained chiefly in the hull. When this indigestible covering is removed in the process of milling, the meal or flour which is left, repre- sents therefore the nutritive part of the grain free from nearly all that is useless for food. Plainly, then, it is upon the composition of this inner part that the value of the grain must principally depend; and here, as we shall see, the most important differences are to be found. 29. Carbohydrates. If we knead a little wheaten dough in a considerable quantity of water, the latter becomes milky from the presence of a pure white substance which washes out from the dough, while there is left behind a curious, elastic, pale-colored mass sometimes called "wheat gum." If we allow the milky water to stand for some time, a large part of the white sul^stance will settle, thus showing that it is a fine powder which was merely suspended in the water, and not really dissolved. This white material is starch, as may be proved by adding to some of it a little iodine solution; this will turn it a dark bluish color, and starch is the only substance known to be thus affected. If starch be boiled with a dilute acid for a sufficient time it becomes mainly converted into a kind of sugar known as glucose, or grape-sugar, an important constituent of the commercial "glucose" of which large quantities are used in confectionery. Chemistrj- teaches us that this change is made possible by the fact that both starch and glucose con- sist of the same elements, — namely, carbon, hydrogen, and 32 CEREALS oxygen in nearly the same proportions, — the composition of starch being carbon, six parts; hy(h'ogen, ten; and oxygen, five; as expressed liy the fornuihi C,;Hi„0-; while for pure glucose the formula is C,;Hi.X),,. It will be noticed that in each there is twice as much hydrogen as oxygen; that is to say these elements are present in just the same propor- tion as in water, which, as is well known, has the chemical formula HoO. A substance which is thus composed of car- bon united with the elements of water is called a carbohy- drate.^ Not only do starch and glucose come under this head, but also other kinds of sugar, various sorts of true gum (such for example as that on postage stamps), and the sub- stance knowm as cellulose of which wood, cotton, and paper are mainly composed. Among the cereal grains, although sugar is sometimes present to a notable degree, as in "sweet corn," the amount of digestible carbohydrate as given in the tables may be understood as being almost entirely starch. During the process of digestion in man and other animals starch is converted into sugar, and as such is absorbed into the blood and carried all over the system to serve either for making fat or for giving warmth and strength. Since only fluids can l)e absorbed, and since starch is composed of solid insoluble particles, the necessity of somehow converting tlie starch of our food into sugar, is obvious. Similarly, when grains sprout, the starch in them under- goes a sort of digestion and becomes converted into sugar, largely maltose or "malt sugar" (formula CioH.oOn)- This being soluble in the sap of the young plant, may be car- ried to the regions of growth where food is needed. This change of the insoluble starch into the soluble sugar is accomplished through the action of a substance called diastase, one of a remarkable class of substances known as enzymes - that have the power of bringing about such changes by their presence in comj^aratively minute amount. The process of malting consists in causing grain to sj^rout and allowing the conversion of starch to proceed until as much ' Car-bo-hy'drate < L. carbo, coal; Gr. hydor, water. -En'zyme<; Gr. en, in; zi/nic, leaven; so called because acting like the substance in leaven or yeast which produces similar changes. PROTEIDS 33 sugar as possible is produced. At this point the j^lantlets are killed by heat so that they will not use up any of the sugar they have made. The sweet substance is then dis- solved out by soaking the malted grains in water. From the liquid so sweetened, lager beer and other malt liquors are made by subsequent fermentation with yeast. Diastase separated from malt may be used instead of an acid to con- vert starch into sugar. 30. Proteids. Let us return now to that other constituent of the wheaten dough, the elastic material which remained after removal of the starch. This is known as gluten i and is a mixture of several substances which belong to the class known as proteids.- To this class belong also the substances which form the chief part of our own flesh and blood — and indeed, mainly constitute the living substance of all plants and animals. Hence, proteids must be regarded as the most precious of all food substances. Like the carbohydrates they contain car])on, hydrogen, and oxygen (though in some- what different proportions), but in addition the}' always have a certain amount of nitrogen, and usually a little sulphur and phosphorus. The nitrogenous nature of the proteids is made evident by the pungent ammoniacal odor which is given off when any of them are burned, — ammonia being NH3. Although in chemical composition proteids are all very much alike, there are important differences in their solubility' — some, like white of egg, dissolving in cold water, while others, such as those of the "wheat gum" are in- soluble. Among the latter is a form of proteid called glufin or gliadin which gives to wheat-gluten its wonderful tenacity and elasticity. It is a significant fact that wheat is the only one of the cereals which contains gliadin in any considerable amount, although it should l)e said that rye contains a closely similar proteid. jVIacaroni, which owes its consistency chieflj' to ghadin, is therefore made only from wheat; and wheaten dough alone possesses just the right tenacity and elasticity for making the lightest, spongiest loaf. The lightest rye bread ' Glu'ten < L. (/lutus, tenacious. 2 Pro'te-id < Gr. protos, before. 34 CEREALS has wheat flour mixed with it. The fact that wheat con- tains in largest amount a nutrient with such remarkable properties as gliadin, is the chief reason why this grain was prized above all others in ancient times, and whj' it has come to be valued more and more highly as civilization has advanced. 31. Fats. One other constituent shown in the chart re- mains to be mentioned. This is the fat or fixed oil, called "fixed" because, unhke the "volatile" oils, it does not evap- orate at ordinary temperatures. A little of this oil msiy be separated for examination b}^ soaking " Avhole wheat" flour, bran, or corn meal in naphtha, and then pouring off the latter into a shallow dish. The naphtha will evaporate, leaving be- hind the oil which it had dissolved. In chemical composition the fats agree with the carbohy- drates in consisting of carbon, hydrogen, and oxj-gen; the difference being that there is always less than half as much oxygen as hydrogen. Like the carbohydrates their use as food is for yielding warmth and strength, and they may make the body fatter; but as in these respects fats are more than twice as effective as carbohydrates their importance In the various grains is much greater than would appear from the comparatively small amounts which are present. This fact enables us to understand the great value of maize, for ex- ample, in fattening animals. With foods rich in oil there is this drawback, however, that after a limited time they are apt to spoil with keeping, while starchy foods remain practically unchanged as long as they are dry. Thus wheat, which contains less oil than maize, keeps better, and its deficiency in this ingredient we fully make up for by eating butter on our bread. CHAPTER III VARIOUS FOOD-PLANTS 32. Classes of food-plants. Having in the last chapter learned something of the uses and importance of the cereal grains, we ma}" now profitably compare with them other food- plants many of which are almost as valuable as cereals al- though in different ways. It will be convenient to study them under the following headings: nuts, pulse, earth-vegetables, herbage-vegetables, fruit-vegetables, fruits, and miscellaneous food-plants. 33. Nuts have, hke grains, an edible kernel; but this is generally much larger than in any grain, and is moreover protected by a much thicker and harder shell. The chestnut (Figs. 24-26), the filbert (Fig. 23), the walnut (Fig. 27), the butternut (Fig. 28), the hickory-nut (Fig. 30), the pecan (Fig. 29), the almond (Fig. 31), the peanut (Fig. 33), the Brazil-nut (Fig. 32), and the coconut (Figs. 34-36), plainly agree in possessing the iDeculiarities named, although they differ considerably from one another. In view of the fact that nuts possess such large edible kernels, and are some of them even richer than the cereals in proteid, the question naturally arises as to why, with us, nuts are so much less used for food than the grains. The many years which must often elapse between the time of planting and the fruit-yield, the much greater bulk in pro- portion to food-material which thej^ occupy when stored, and the additional labor required for separating the nutritive from the inedible part, are doubtless the drawbacks which very largely account for the inferior rank of nuts in our market; but there are also chemical reasons which will be apparent upon consulting the chart on page 114. With the exception of the chestnut, all we have mentioned contain an 35 30 VARIOUS FOOD-PLANTS Fig. 23. — Filbert or Hazelnut (Carylus Avclluna, Hirch Family, Bctulaccce) . 1, a twig bearing on the right two loose, hanging, yellowish flower- clusters eonsisting entirely of staminate flowers and their scale-like bracts, and on the left and at the tip, two pistillate flower-clusters enclosed ^ by bracts and bud-scales which permit only the crimson stigmas to protrude (natural size). 2, a single staminate flower, viewed from below, showing the numerous stamens and the scale to which they are attached (enlarged, the vertical line at the right showing the natural size). 3, a single stamen (enlarged). 4. a pistillate flower, cut vertically through the ovary, showing the two ovules (only one of which commonly ripens into a seed), the short style, and two stigmas which protrude beyond the bract-cup (enlarged). 5 , the fruit, partially enclosed by the now leafy bract-cup. 6, the nut removed, showing the scar where it was attached at the base. (5 and 6, natural size.) (Wossidlo.) — The plant is a shrub or small tree ' 3-10 m. tall, much branched; twigs ash-colored, sticky-hairy; bark on older stems mottled bright brown and gray; leaves downy below; nuts brown. ' Shrulis and trees are distinguished from herbs by hdving woody stems above ground which live from year to year. A tree is a self-supporting woody i)lant which becomes several times taller than a man, and forms a single main trunk. A shrub diff'ers from a tree in being usually of less height and having many well-developed branches starting from near the ground in place of a main trunk. NUTS 37 enormous proportion of oil. This, although of use as food, renders nuts more difficult of digestion than grains, and causes them to spoil with keeping after a comparatively short time. Fk;. 24. — rhestnut (Cnstanea sativa, Beech Family, Fagacecr). A leafy twig, bearing flower-clusters composed mostly of yellowish, staminate flowers with a few greenish pistillate flowers near the base. About one-quarter natural size. (Baillon.) — The plant is one of the largest forest trees of the north temperate zone, sometimes in forests attain- ing a height of 30 m. Bark, on the trunk and older branches, dark, very hard, and with long deep clefts; when younger smooth and lighter colored; young twigs deep green, bronzed or purplish brown, covered with whitish dots. Leaves, polished, bright green above, smooth and paler below. In spite of their disadvantages, however, chestnuts, wal- nuts, and peanuts form a very important part of the food of many Europeans, largely taking the place of cereals. In many tropical regions where cereals do not grow, immense 38 VARIOUS FOOD-PLANTS quantities of peanuts and Brazil-nuts are eaten, while in some places the coconut constitutes the chief, sometimes almost the only, food. The importance of nuts, to mankind, Fig. 25. — Chestnut. A, twig bearing two clusters of pistillate flowers, and a small immature cluster of staminate flowers. B, a single clu.ster of three pistillate flowers protruding from among the bracts which form a cup around them. C, a single pistillate flower, showing six elongated stigmas and a bell-shaped calyx of si.x sepals formed above the ovary. D, the same, cut vertically to show the ovules at the base of the flask-shaped ovary. E, a single staminate flower, showing the numerous stamens surrounded by the calyx of six sepals joined at the base. The figures all somewhat enlarged. (Baillon.) /;;/'/j.;:^r Fir.. 26. — Chestnut. A, ripe fruit, showing the now spiny bract-cup or "burr" split open and exposing three nuts within. Reduced. B, one of the side nuts, showing at tlie tip the stigmas and calyx. About two-thirds natural size. C, the middle nut. showing the scar of at- tachment at i)ase. D, a side nut, cut vertically to show the seed within containing a large embryo gorged with starchy food. (Baillon.) therefore, is much greater than we commonly suppose, con- sidering that with us they are used scarcely more than as luxuries. NUTS 39 Fig. 27. — Walnut (Juglans regia, Walnut Family, J uglandacew) . 1, a spring shoot bearizig young leaves; at «, a staminate flowcr-elu.ster, and at 6, a cluster of three pistillate flowers. 2, a single staminate flower viewed from below, showing the numerous stamens, and three sepals and three bracts which cover them above; a, inner view of a single stamen; b, the same in side view. 3, a single pistillate flower, showing the two spreading stigmas protruding beyond the small calyx, which crowns the ovary. 4. the same cut vertically-, showing the single ovule at the ])ase. 5, a fruit with part of the husk removed, showing the rough-shelled nut within. 6, nut cut in half vertically, showing half of the four-lobed seed or "meat," within. (Wossidlo.) — The plant is a handsome, widely spreading tree attaining a height of 20 m. Bark soon becoming thick and much cracked. Leaves smooth, dull green, bronzy to yellowish. Flowers greenish. Fruit-hull, green turning black. Wind carries the pollen from tree to tree. 40 VARIOUS FOOD-PLANTS Fui. 2N. — Butternut {Juglans cinerea, Waluut Family, Ju5?Za«'/acea?). A twig in autumn bearing a single leaf and a ripe fruit. Twig, in spring bear- ing two staminate flower-clusters. A single starainatc flower viewed from above. A pistillate flower showing the two protruding stigmas. A nut removed from its husk, showing the deeply sculptured shell. The flowers, enlarged; the other parts reduced. (Britton and Brown.) — The plant is a forest tree becoming sometimes .30 m. tall; old bark roughish, gray; young twigs and leaves sticky-hairy; flowers brownish green; stigmas red; fruit green turning to brown, covered thickly with verj- sticky hairs, nut l)lackish. Fig. 29. — Pecan (Carya olivcEformis, Walnut Family, Juglandacece). Twig in spring after removal of all the leaves but one and all the staminate flower-clusters below it except the lowor piirt of their stalks. At the tip of the twig is the small cluster of pistillate flowers. Three-branched staminate llower-cluster. Staminate flower, top view. Stamen. Fruit. Nut, after rcmo\al of the husk. Flower and stamen, enlarged. (Britton and Brown.) — The plant is a large slender tree, becoming 50 ni. tall; bark somewhat rough; young twigs and leaves hairy; mature foliage nearly smooth; flowers greenish; fruit brownish green; nut light brown. The native home of the various nuts and of other food- plants, the length of time they have been cultivated, and certain other matters of related interest, will be discussed at the end of this chapter. 34. Pulse, under which name are included peas (Figs. 37, 38), and beans (Figs. 39, 40), 'agree with grains and nuts ' In the reforencp to the illustrations the reader will ob.serve that the same Arabic numeral sometimes applies to more than one cut, Roman PULSE 41 Fig. 30. — Shagbark Hickory (Carya alha. Walnut Family, J uglandarcw) . A single leaf. Staminate flower-clu.ster. Staminate iiower, under «idc, enlarged. Twig bearing a single fruit. Nut. (Britton and Brown.) — A large tree becoming 3G m. tall; bark shaggy in narrow plates, gray; young twigs and leaves slightly hairy becoming smooth; flowers green- ish; fruit greenish brown; nut almost white. in that the nutritive part is contained within the seed, but differ from them in that the seeds ripen in a rather thin- walled pod which opens at maturity by splitting in halves from end to end. The very large amount of nutriment in proportion to bulk, together with the small percentage of water and oil (see chart) renders beans and peas among the very best foods for storage, and particularly adapts them for use upon long voyages. That they are highly nutritious is shown by the large amount of proteid they contain. This, however, is found to be of a sort resembling the proteid of cheese; and is not so easily digestible as that found in cereals. 35. Earth-vegetables we shall find to be a convenient numerals being added to distinguish them. Tlius in the above refer- ence to the pictures of kidnev-bean, Fig. 39 is understood as applying to Fig. 391 and Fig. 3911. 42 VARIOUS FOOD-PLANTS Fig. 31. — Almond (Prunufs j{>nyodalus. Rose Family, Rosacea;). A, twig bearing one unopened winter-bud and a cluster of j-oung leaves ex- panding from another. B, a flowering branch. C, a single flower. D, the same cut vertically to show the single jiistil with its small ovary at the base of an urn-like continuation of the flower-stalk at the rim of which are borne three sets of organs, namely: the stamens which are numerous and in two rows; then outside of these a single row of deli- cate enveloping organs, the petals, '^ which in the almond flower are * We have here an example of a "complete" flower or one which has all the kinds of organs which are commonly present; that is to say, besides the EARTH-VEGETABLES 43 term to designate those garden esculents of which the nutri- tive part grows in the earth. This echble part may be either a root-tuber as in the sweet potato (Figs. 56, 57), a crown-tuber as in the beet, turnip, radish, carrot, and parsnip (Figs. 41- 55), or it may be a stem-tuber as in the white potato and the Jerusalem artichoke (Figs. 59, I-IV), or a bulb as in the onion (Figs. GO, 01). A root-tuber consists entirely of a swollen root gorged with reserve food. A crown-tuber bears a crown of leaves more or less rosette-like, thus showing it- self to be part stem and part root. By the term "tuber" botanists sometimes mean only a stem-tuber, but the word is more conveniently applied in a general sense to all short and much thickened roots or stems. A stem-tuber differs from a root-tuber in having "eyes" or buds regularly arranged in httle pits along the sides; and from a crown-tuber in bearing no foliage-leaves, but instead minute appendages, one below each eye. If a stem-tuber be made to sprout, the buds will grow into leafy branches. A bulb differs from a tuber in consisting chiefly of readily separable scale-like parts or layers which are mostly succulent. As will be seen from the chemical chart (page 114) the very large percentage of water in earth-vegetables presents a striking contrast to what we find in grains, nuts, and pulse. Notice also, particularly in the roots, the comparatively white or rose-colored and five in number; and finally, outside of all, a row of sepals, which are green, and five in luimber. G, a twig bearing three leaves and two fruits of which one is shedding its leathery husk. H, a single fruit. /, the same, with half the husk removed, to show the nut which appears above with half its shell removed to reveal the seed v.-ithin. E, the seed, covered by its thin brownish coat. F, the embryo gorged with food, shown after removal of the seed-coat. All more or less reduced in size. (Baillon.) — The plant is a tree closely resembling the peach tree in general form and in every part except the fruit. The flowers, appearing in very earlj' spring, before the leaves, are re- markably beautiful. The fruit of the almond closely resembles a green peach; it differs from the peach mainly in having in place of the hard-shelled "stone" a rather soft-shelled nut which is covered by a leathery husk that commonly splits open when ripe. pistil and stamens which are known as the "essential organs," and the sepals which constitute the calyx or outer floral envelope, it has an inner envelope made up of petals distinctly different in appearance from the sepals. The petals taken together constitute what is called the corolla, or "little crown" of the flower, and form commonly the most conspicuous part. The calyx and corolla taken together are called the perianth, especially if they are closely similar in appearance. 44 VARIOUS FOOD-PLANTS Fig. 32. — Brazil Nut {Bertholletia excelsa. Myrtle Family, Myrtacem). A, flower-eluster and leaf. B, expanding flower-bud viewed from below showing the under side of the tvVo sepals. C, the same from above, showing upper side of sepals, and the six petals. D, the numerous stamens united bj' their filaments into a hoodlike body. E, upper part of a stamen enlarged. F, ovary cut across, to show the four cavities containing ovules. G, a single one of these cavities cut into lengthwise, giving a side view of the ovules, enlarged. H, fruit, with the upper part of its thick spherical wall removed to show the seeds within, packed about a central spindle. A part of the outer, softer layer of the wall is torn away in front, showing the channelled surface of the very hard inner layer. J , the central spindle. A', a nut in side view. L, the VARIOUS FOOD-PLANTS 45 same cut across through the middle, to show the thick seed-coat with its thin hiyers, and the large germ which fills it. M, germ, removed, showing the general form and the absence of distinguishable parts. (Berg, Humbolt, and Bonpland.) — -The plant, which is one of the most majestic trees of the Brazilian forests, reaches a height of over 30 m.; leaves bright green; flowers with cream-colored corolla; fruits "nearly as hard and heavy as cannon-balls, fall with tremendous force from the height of 100 feet. . . . Persons are sometimes killed by them" (Wallace). Fig. 33.— Peanut {Ara- chis hypogcea. Pulse Family, Leg amino see) . A, lower part of a plant showing the leaves and flowers above ground, and ripening nuts and roots below; the sur- face of the ground be- ing indicated at cl. B, a flower cut vertically to show, at the base, the small ovary con- taining the ovules, and the long style extending through a slender tube which is surmounted by the calyx and corolla and is con- tinued by a tube formed of the united filaments. C, a ripe nut cut lengthwise to show the two seeds. (Tanbert.) — The plant is an annual, ?'. tion through the fruit sprouting; notice the thick husk into and through which the young roots grow, the hard shell of the nut (shown black) within which is the layer of solid seed food (coarsel\- dotted), and the lifjuitl food or "milk" (white) into which the enlarging cotyle- don or "seed-leaf" (finely dotted) pushes its way and acts a.s an organ of absorption. (Warming.) — The husk is smooth and grayish brown, and is largely composed of coarse, tough fibers. VARIOUS FOOD-PLANTS 47 ^iG. 3G.— Coconut. A, flower-cluster with one of the immense bracts which envelop it while young, showing staminate flowers in upper part of branches, and pistillate ones near the base, much reduced. B, staminate flower. C, pistillate flower. B and C slightly reduced. (Original drawing from photograph.) — The flowers and enclosing bracts are various shades of yellow. 48 VARIOUS FOOD-PLANTS Fig. 37. — Pea (Pisum sativum. Pulse Family, Legumiiios(e) . Plant in flower and fruit, niueli reduced. (Nicholson.) — T h c plant is an annual, climbing by mean.s of tendrils which termi- nate the leaves; stern and leaves pale green, smooth and covered with a delicate "bloom " which easily rubs off; flowers, white, bluish, purplish, or variegatcil. ri(i. 38.— Pea. A, flower. B, the same halved. B', corolla, with petals separated, showing standard (e), wings (a, a), and keel (c). C, the stamen-tube and pistil, enlarged. D, pistil. E, pod shedding seeds. F, a seed, showing stalk (/), place of minute opening, the mi- cropyle, through which moi.s- ture penetrates (m), raphe or ridge (r) and chalaza or end of ridge (c) ; G, embryo, laid open, showing cotyledons or seed-leaves (c), radicle or seed- root (r), caulicle or seed-stem (t), and plumule or seed- bud (g). (Warming.) VARIOUS FOOD-PLANTS 49 Fig. 39 I. — Kidney Bean (Phnseolus vulgaris, Pulse Family, Leguminosm). Plant of a twining, "running" or "pole" variety in flower and fruit X h- (Vilmorin.) — The plant is a rough hairy annual vine or, in cer- tain "dwarf" varieties, a bushy herb; flowers of various colors in- cluding white and lilac ; fruit and seeds also of different colors and very variously marked. 50 VARIOUS FOOD-PLANTS Fig. 39 II. — Kidney Bean. A , flower, about twice natural size. B, the same with wings pressed down as if by a bee sucking nectar; showing the stigma and policn-covcrcd end of the style protruding from the coiled tubular keel. A bee's head or back covered with bean pollen would be in position to deposit some of the grains upon the protruding stigma and thus enable the plant to set good seeds, while an instant later it would be touched by the pollen on the style and so receive a new load to take to another l)can-flower. C, a flower cut in halves vertically to show the arrangement of parts before protrusion of the stigma. Enlarged and somewhat diagrammatic. (Original.) VARIOUS FOOD-PLANTS 51 Fig. 40. — Lima Bean {Phaseolus lunatus. Pulse Family, Leguminosm). Plant of a twining variety in flower and fruit x jV. (Vilmorin.) — The plant is an annual closely resembling the Kidney Bean except that the flowers are greenish white and the pods are broad, flattened, and curved like a scimitar. large amount of indigestible material (cellulose) in propor- tion to the proteid and other nutritive constituents. From this it follows that not only are earth-vegetables more bulky to store than grains and pulse (and, moreover, cannot or- dinarily be kept longer than a few months) but in order to 52 VARIOi:S FOOD-PLANTS r^''^-^!^ Fig. 41. — Beet. (Beta vulgaris, Goose- foot Family, Chenopodiacecp). Plant showing the appearance of the parts above ground at the end of its first year. X \. (Original). — The leaves are smooth, green or more or less tinged with red; stem scarcely more than a "crown" covering the top of the swollen root which projects some- what above the ground. Fig. 42. — Beet. A plant in its second year, the underground parts cut ver- tically, to show the swollen root which is feeding with its store of nutriment the crown, which has given ri.se to several erect l^ranches bearing leaves, flowers and fruit. (Original). — Plant, a biennial, i. e., requiring two years to complete its life, the first year storing up food which during the second year it uses to build flower- and fruit-bearing shoots; stem- branches, commonly deep red; flow- ers, greenish; fruit, dry, rough, and brown, HERBAGE-VEGETABLES 53 C H Fig. 43. — Beet. A, root. B, leaf. C, small flowerint; branch. Z>, a flower just opened. E, vertical section of a flower-bud showing a bract, (h), a layer of crystals in the ovary wall, k, and, nectar glands (f/, d). F, stamen, back view. G, a flower the same as D but older. H, seed. J, the same cut in half, to show seed-coat and the germ coiled around the seed-food in the center. A-C, reduced, D-.J variouslj- enlarged. (Baillon, Volkens.) get as much nutriment from them as from grains or pulse, a very much larger amount must be eaten. It should not be supposed, however, that the indigestible parts of what we eat are altogether useless; for it has been observed in various experiments that digestive organs commonly work to better advantage when the nutritious materials undergoing diges- tion are present not in concentrated form but diluted, as it were, with a certain amount of finely divided cellulose or other harmless material which may act mechanically. 36. Herbage-vegetables may be defined as those which yield us nutriment in shoots developed above ground. They 54 VARIOUS FOOD-PLANTS Fig. 44. — Turnip. (Brassica campestris, Mustard Family, Crucifcrce). Plants showing fleshy roots, and rosettes of leaves, as they appear at the end of the first year's growth. X s. (Vilmorin.) — Plant a biennial; root varying greatly in form and color under cultivation; leaves bright green; rough-hairy. Fig. 45. — Turnip. Middle section of second-year stem which bears the flow- ers. A lower leaf. Flower-cluster with young fruit. Fruit, natural size. (Britton and Brown.) — The plant in its second year becomes about 1 m. tall or less; the lower leaves are hairy, the upper ones smooth ; the flowers yellow. HERBAGE-VEGETABLES 55 Fig. 46. — Radish. (Rn phatius satiims, Mustard Family, Crucifera). Fig. Part of .stem bearing leaves. Flower cluster. Fruit. (Brit- ton and Brown.) — Plant an an- nual, or in rultivation behaving as a biennial: roots flattened, spherical or long-conical, vari- ously colored, mostly white or red ; stem and leaves bright green, more or less covered with stiff hairs; flowers pink or white. 47. — Carrot {Daucus Carota, Par.s- ley Family, Umbelliferce) . Plant showing root and rosette of leaves at the close of the first year's growth. (Nicholson.) — The roots vary considerably as regards form and color, being conical, cylindri- cal, or globular; red, orange, yel- low, or white; and from about 5-.50 cm. long; leaves bright green, hairy. include ''pot-herbs" and certain "salads." The most nutri- tive part is in some cases the tender and more or less thick- ened stem, as with asparagus (Figs. 62 1, II) and kohlrabi (Fig. 66). Sometimes as in kale, borecole, cabbage, and Brussels sprouts (Figs. 63-65, 67-69), watercress (Fig. 71), spinach (Figs. 72-74), and lettuce (Figs. 75-77) the leaves are of most importance. With celery (Figs. 78, 79) the leafstalk is the part employed, while in the cauliflower (Fig. 70) it is the much branched and thickened flower-stalk, together with the innumerable buds which it bears. In chemical composition, and consequently in food value, 56 VARIOUS FOOD-PLANTS Fig. 48. — Carrot. Upper part of plant in flower and fruit. (Baillon.) — Plant a biennial, becoming about 1 m. tall; flowers mostly white, the central one of a cluster being usually dark purple. Fio. 49. — Carrot. Flower, enlarged. (Baillon.) Fig. 50. — Carrot. Flower, cut in half vertically. (Baillon). VARIOUS FOOD-PLANTS 57 Figs. 51-53. — The three upper figures. Carrot. Diagram of flower, showing tlie arrangement of the parts as they would appear if cut across and viewed from above. Fruit, viewed from the side. Enlarged. Fruit, cut across, showing oil-tubes, at the bases of the long spines. (Baillon.) Fig. 54. — Parsnip {Pastinaca sativa, Parsley Family, Umbrllifera). Plant at close of first year's growth, showing fleshy root and a few of the young- er leaves, the older ones having been cut off. (Nicholson.) — The root varies somewhat in form but is commonly conical; the flesh whitish or pale yellow. Fig. 55. — Parsnip. Part of leaf, reduced. Part of fruit cluster, reduced. Fruit, enlarged. D, half of the same cut across. (Britton and Brown.) — Plant a l)iennial or sometimes an annual, smooth or somewhat hairy, becoming 0.6-1.5 m. tall; leaves bright green; flowers similar in form to those of the carrot, t)ut somewhat larger and yellow. Many insects are attracted by the clustered flowers. 58 VARIOUS FOOD-PLANTS Fig. 56. — Sweot Potato (Ipomaca Batatas, Morniug-Glory Family, Con^ volviilaceoe) . Stem, leaves and roots. X i. (Redrawn.) — Plant a per- ennial (i. e. growing more than two years) with creeping stems be- coming 2-3 m. long; leaves dark green, glossy; flowers purple, closelj' resembling those of the common morning-glory; roots becoming fleshy, sweet, and yellow within; fruit dry. herbage-vegetables are found to be a good deal like earth- vegetables. The chief difference is that the former have, on the whole, a somewhat larger percentage of water, and a smaller amount of digestible carbohydrate. As against these deficiencies, however, there is a- decidedly larger proportion of proteid in relation to the other nutritious materials. For example in lettuce which has at once the most water and the least proteid of any of the herbage-vegetables given in the table, we find that a])out one-third of the nutritive material (representing nearly one-quarter of the total weight exclusive of water) is proteid; while in the sweet potato (which of all the earth-vegetables given, ha.s the least water and next to the most proteid) the proportion of proteid to other nutrients is approximately 1 to 12 (being to the total weight of the material dried, nearly as 1 to 18). VARIOUS FOOD PLANTS 59 Fig. 57. — Sweet Potato. Flower-clusters coming from leaf-axils, *. Flower, cut vertically; natural size. Fruit, j. Seed, cut in half verticallj' to show the folded germ in seed-food (dotted) , t. (Original.) Fig. 58, I. — White Potato (Solaiium tubcrosinn, Night- shade Family, So- la nacca). Base of plant growing from an old tuber a n d producing new tubers at the tip of under- ground branches of the stem. (Baillon.) — Plant a perennial con- tinued from year to year by its tu- bers; stem erect, about 0.7 m. tall; leaves dull green, hairy; flowers lilac or white; fruit fleshj-, green. m VARIOUS FOOD-PLANTS Fig. 58, 11. — White Potato. Flowering brancli. (Baillon.) Fig. .58, III. — White Potato. A, flower, about natural size. B, flower cut vertically, enlarged. C, stamen, enlarged, showing at the tip of the anthers the pores through which the pollen escapes and falls upon an insect visitor. D, berry, inside view. E, same, cut across. F, seed, side view, and cut vertically to show the curved germ and the seed- food. (Baillon.) VARIOUS FOOD-PLANTS 61 Fig. 59, I. — Jerusalem Artichoke. (Helianthus tuberosus, SunfloM'cr Family, Composilw). Stem-tubens at base of stem, producing -slender roots. (Vilmorin.) — The plant is a perennial herb, often 2 m. in height, closely resembling an ordinary garden sunflower. MM Fig. 59, II. — Jerusalem Artichoke. Flower-cluster cut vertically to show arrangement of the perfect florets forming a central mass or "disk," the neutral ray-florets surrounding them, and the protecting bracts or "involucre" looking like a calyx outside of all; the whole growing from the so-called "receptacle" or expanded top, of the floral stalk. (Baillon.) — Such a compact cluster of two kinds of flowers looks like one huge fiower, and consequently becomes very attractive to many insects which transfer its pollen advantageously. 52 V AKIO IS ¥( )( )D-PLANTS Fig. 59, III. — Jerusalem Artichoke. A, disk flower enlarged and out ver- tically to show the single pistil with two stigmas, long style with nectar glands at base, and one-celled ovary containing a single erect ovule; appearing above the ovary is a tubular corolla dividing into five petal- tips (of which but three are shown), and bearing as many stamens the anthers of which are united into a tube; also appearing above the ovary are slender Sepals; and at the ba.se of the flower a chaffy bract from the axil of which the flower arises. A neutral ray-flower having no stamens and only the vestige of a pistil in its rudimentary ovary, but showing a chaffy bract at its ba.se, several sepals, and a much enlarged corolla formed as if by the splitting of a tube nearly to the bottom along its inner side. (Baillon.) Fig. 59, IV. — Jerusalem Artichoke. Fruit, side view, enlarged. The same cut \'ertically to show the germ occupying the whole of the seed within. (BaUlon.) VARIOUS FOOD-PLANTS 63 Fig. 60. — Onion. (Allium Cepa, Lily Family, Liliaceae). A, bulb at the beginning of the second year's growth (i) cut to show the short stem from which roots spring below, and, above, last year's leaves of which there remain only the thickened bases forming the "coats of the onion" and filled with food now being used up by the new leaves de\eloping from a bud at the center. B, upper part of a leaf cut to show its tubular form. C, plant toward the end of its second year {h) ; the upper (once green) part of the leaves having withered, are replaced by a green hollow stem (shown cut across at D) which bears a cluster of white flowers, and finally the fruit. (A, original; B, C, D redrawn from Reichcnbach:) 64 VARIOUS FOOD-PLANTS Fig. G1. — Onion. .4, flower, enlarged. B, three stamens, showing their unequal size, and connection at the base. C, young pod. D, the same cut across to show the three compartments and their seeds. E, dry pod split open naturally to release the seeds. (Redrawn from Reichenbach.) Fig. 62, I. — Asparagus {Asparnrpix officinalis, Lily Family, Liliorea). Mass, of roots and fle.sliy .spring shoots, x I'o (Nichol.son.) — Plant, a perennial, of the seashore, sending up from its matted roots erect shoots which arc at first simple and succulent but .soon much branched and firm, aliout 1..'5 m. tall, and of a pale green color; flowers greenish J'ellow; fruit fleshy, bright red. HERB AGE- VEGETABLES 65 Fig. 62, II. — Asparagus. .4, upper part of a flowering branch. X J. B, flower, enlarged. C, perianth and stamens of the same spread out. D, stamen, outer view. E, pistil. F, cross section of ovary. G, flower cut in half vertically. H, Diagram showing the arrangement of the parts of the flower. J, fruit, natural size, iv, seed, enlarged, and in vertical section. (LeMaout and Decaisne.) The relatively large proportion of mineral matter in the dry substance, ?'. c, the entire substance free from water, of succulent vegetables and fruits deserves particular notice, for there is good reason to believe that certain salts here in- cluded impart to the fresh juice of these plants a peculiar value quite independent of their worth as nutriment. It has been observed that when, as on long voyages, men are de- prived of food containing such vegetable juices, a serious and often fatal disease, kno■\^^l as scurvy, is likely to attack them. Sea captains and military commanders are now required by law to supply this need in the rations of their men (hme- juice is very largely used for the purpose), and scurvy is no 66 VARIOUS FOOD-PLANTS D F Fu;. 63. Wild Kale (Brassicn ohracca, variety syhestris, Mustard Family, Crucifira). A, plant in its first year showing rosette of leaves, nmeh reduced. B, upper jnirt of flowering stem developed the second year. Slightly reduced. C. a flower. D, a sepal. E, a ])etal, enlarged. F, essential organs of the flower. 6', fruit. (A, Redrawn from Bailey, the others from Roichenhach.) — The plant is a liiennial growing wild on rocky seashores, the first year producing only a rosi-tte of lca\-es and the second year attaining often a height of 1 m.; st( in and leaves rather fleshy, pale bluish green, smooth, covered with a waxy bloom; flowers yellow. HERBAGE-VEGETABLES 67 Fig. 04. — Wild Kale. A, flower cluster. B, flower with caly.x and corolla removed to show the stamens and pistil. C, fruit. D, the same split- ting open and exposing the seeds. E, seed cut across to show the folded parts of the germ within the seed-coat. (Baillon.) longer feared. As these vegetable juices possess scarcely any nutritive value, the above facts clearly indicate that special salts dissolved in the juices have an important use in keeping our bodies in healthy condition. The difference in chemical composition and food value between herbage-vegetables and the various underground parts and seeds already studied may be accounted for by the peculiar purpose which green herbage serves in the plant's life. Whereas food is stored abundantly in parts which are to live over the winter in order that new growth may be hastened at the return of favorable conditions, it is the foliage which makes the food that is stored away. The making of food requires sunlight, and is accomplished by means of the green coloring matter characteristic of herbage. This pigment is termed chloi'ophyllJ It dissolves in alcohol, and the extract possesses the peculiar property ^ Chlo'-ro-phyll r >W (das' "^l^cCifc? ■^ml^;.? Fig. 68. — Savoy Cabbage (B. oleracea, var. sabauda). Plant at close of first year's growth, showing the characteristically blistered leaves. Much reduced. (Nicholson.) Fig. 69. — Brussels Sprouts {B. olcracea, var. gemniifera). Plant at close of first year's growth. Much reduced. (Nicholson.) 70 VARIOUS FOOD-PLANTS Fig. 70. — Cauliflower (B. oleracea, var. Botrytis). Plant at close of first year's growth, with a few of the leaves cut away to show the fleshy, compacted flower-cluster. Much reduced. (Baillon.) Fic,. 71, I. — Watercress {Nasturtium officinale. Mustard Family, Cruciferoe). Plant showing method of growth, (x \) and a piece of stem hearing roots, leaf, and a young l>raiich, natural size. (\'ilmorin.) HERBAGE-VECJETABLES 71 Fig. 71, II. — Watercress. Flowering branch. Flower (petals white). Fniit. Piece of pod cut lengthwise to show the two rows of seeds. (Britton and Brown.) Fig. 72. — Spinach {Spinacia oleraccu, (Joo,sefoot Family, Cht^nopodiacece). Plant, showing first year's rosette of leaves. (Vilmorin.) — An annual or sometimes a biennial; leaves smooth, deep green; flowers greenish; fruit dry. 72 VARIOUS FOOD-PLANTS Fig. 73. — Spinach. Flowering branch. (Baillon.) Fig. 74. — Spinach. -1, staminate flower, top view. B, pistilhite flower, side view. C, pistil, with part of ovary wall cut away to show the ovule within. Z>, fruit. E, the same, cut in half vertically showing seed and coiled germ. F, G, other forms of fruit. All the figures more or less magnified. (Volkeiis.) Fig. 75 Lcitud [J.ddiui ^alua >uuflo\\(i 1 imiK i otn po'^ita) Plant during early period of growth, showing the compacted rosette of leaves. (Nicholson.) — The i)lant is an animal, smooth throughout, att.nining a height of about 1 in., flowers yellow. HERBAGE-VEGETABLES 73 Fig. 76. — Lettuce. Plant in flower and fruit. (Atkinson.) — This is the wild form known as Lactuca scariola from which the garden varieties are believed to be derived. When growing in open land the leaves com- monly arrange themselves in two vertical rows with one edge directed upward and the tips ijointing northward or southward. It is thus a "compass plant" similar to that of our western prairies described by Longfellow in Evangeline, Part Second, Section IV. The parachute-like fruits are carried far by the wind, and are finally anchored by means of the spines near the base of the stalk. 74 VARIOUS FOOD-PLANTS Fig. 77. — Lettuce. Flower cluster, enlarged. Ba.se of a flower cut ^•e^tically to show the single ovule within the ovary, and how the calyx, corolla, and style grow out from it above. A single flower. An anther, inner view showing openings through which pollen is shed upon the style. The stamen-tube formed by union of the five anthers. Style and stigmas, showing the hairy region which pushes up through the stamen-tube like a bottle-brush carrying upon it the pollen to be rubbed off by insect visitors. (Redrawn from Thome.) When the raw materials above mentioned are present in a living part containing chlorophyll and exposed to sunlight, the energy of the sun's rays is utilized to separate the oxygen from the carbon and unite the latter Avith the elements of water to make a carbohydrate. The first food-product that we can detect is u.sually starch, but the giving off of oxygen (especially well seen in a water-plant) is evidence that food- making is in progress. Fats and proteids may be formed from car])oh3-drates in various parts of the plant independently of sunlight; but while fats require only a diminution in the amount of oxygen, the proteids must have nitrogen, and often sulphur or phos- phorous (derived from the salts above mentioned) combined with the carbon, hydrogen, and oxygen of the carbohydrates. Other elements found in the mineral salts aid in food-making by their mere presence. Thus a minute amount of iron is necessary to the formation of chlorophyll, and potassium herbage-vegetabi.es Hi? Fig. 78. — Celery (Apium graveoleus, Parsley Family, UmhcllifercE). Plant in its first year, showing leaves and roots. (Nicholson.) Fig. 79. — Celery. Leaf. Upper part of flowering stem, showing flower clusters and fruit. A flower, enlarged. Fruit. The same cut across. (Britton and Brown.) — The plant is a biennial, smooth throughout; leaves 25-50 cm. long, bright green (except when "blanched" by cul- ture); flowering stem, erect 3-9 dm. tall; flowers white; fruit, dry, brown. The plant as it grows wild in salt marshes and by the seashore is somewhat poisonous, but becomes wholesome in cultivatif)n. 76 VARIOUS FOOD-PLANTS Fia. 80, I. — Pumpkin {Cuciirbita Pcjto. Gourd Family, Cucurbitnccac). Flowering branoh. (Baillon.) — Tho plant is an annual climbing more or less by means of tendrils, and attaining a length of 7 m.; stem and leaves bright green, bristly hairy; flowers yellow; fruit variously colored in different varieties, and widely different in appearance as shown in Figs. 81, I-IV. controls the making of carbohydrates, although neither the iron nor the potassium enter into the product. Much of the process of food-making as well as of the conditions under which it takes place, is as 3'et imperfeetlj^ understood by physiologists. A living plant has been well compared to a food-factor}^ where we may see the raw materials which go in and the products which come out, but where we can only guess as to what goes on inside, for on the door is written "No ad- mittance." We know that in some way the body of a plant is built up of highly complex materials which it makes by recombining the elements of relatively simple substances. We know also that so long as it lives the plant is breaking down the complex compounds into simpler ones which it gets VARIOUS FOOD-PLANTS 77 Fig. 80, II. — Pumpkin, staminate flower, cut vertically. (Baillon.) Fig. 80, III. — Pumpkin, the same with calyx and corolla removed to show the united stamens, enlarged. (Baillon.) Fig. 80, IV. — Pumpkin, pistillate flower, cut vertically. (Baillon.) Fig. so, V. — Pumpkin, the same with calyx and corolla removed to show the three-branched style and stigmas. (Baillon.) 78 VARIOUS FOOD-PLANTS Fig. 80, VI. — Pumpkin, ovary cut across near the top. (Baillun.) Fig. 80, VII. — Pumpkin, ovary cut across near the middle, showing the position of the ovules. (Baillon.) Fig. 80, VIII.— Pumpkin, seed. (Baillon.) Fig. 80, IX. — Pumpkin, soed cut lengthwise between the seed-leaves of the germ. (Baillon.) Fig. 81, I. — Pumpkin, fruit, ^. Color graj-ish green. (Vilmorin.) VARIOUS FOOD-PLANTS 79 Fig. 81, II. — Long White Squash {Cucurbita Pepo, var.). Fruit and leaves. 6. Fruit pale, yellowish. (Vilmorin.) Fig. 81, III. — Summer Crook-neck Squash (Cucurbita Pepo var.). Fruit and leaves, a. Fruit bright orange. (Vilmorin.) 80 VARIOUS F()(JD-PLANTS Fig. 81, IV.^Scallop Squash (Cucurbita Pepo, var.). Plant showing leaves, flowers, and fruit, is. Fruit pale, yellowish. (Vilmorin.) Fig. 82, I. — Hubbard Squash {Cucurbita maxima, var.. Gourd Family, Cuctirbitaceoe). Fruit. J. (Vilmorin.) — The plant as regards stem, leaves and flowers, resembles the preceding species; fruit variously colored. VARIOUS FOOD-PLANTS 81 Fig. 82, II. — Turban Squash {Cucurhitn maxima, var., Gourd Family, Cucurhitaceae). Leaves and fruit, b. Fruit greenish, yellowish, or reddish. (Vilmorin.) Fig. 83. — Winter Crook-neck Squash (Cucurhila moschata, Gourd Family, Cucurhitaceae). Leaf. Flowering branch. Pistillate flower. Staminate flower. Staminate flower bud, showing leaf-like sepals. (Nicholson.) — Plant similar to the preceding species, but soft-hairy and the leaves often with silvery spots; fruit variously colored. 82 VARIOUS FOOD-PLANTS Fig. 84. — Winter Crook-neck Squash. J. Fruit and leaves. (\'ilnu)riii.) Fig. 85. — Cucumber (Cnciimis safiiKS, Gourd Family, Cucurbitaceoe). Flowering branch. (Nicholson.) — Plant a rough hairy annual, climb- ing by tendrils; stem about 1-2 m. long; leaves bright green; flowers yellow; fruit variously colored, smooth or prickly. ^'ARIO^S FOOD-PLANTS 83 Fig. 86, I. — Cucumber. Staniinate flower, cut vertically. (Baillon.) Fig. 86, II. — Cucumber. Pistillate flower, cut vertically. (Baillon.) Fig. 87. — Cucumber, fruit. (Nicholson.) .1 Fig. 88.— Tomato (Solanum Lycopcrsicum, Xightshade Family, Sola- nacew). Plant in fruit. ,'5. Fruit. 3. (Vilmorin.) — An annual; stem and leaves soft hairy, dull green: flowers yellow; fruit red or yellow. 84 VARIOUS FOOD-PLANTS Fig. 89. — Tomato. Hower, cut vertically, enlarged. Fruit, side view. Same, cut across. Seed, cut vertically to show curved germ, in seed- food. (Redrawn from Nees.) rid of as well as it can or allows to accumulate where they will do the plant no harm. The coloring matters and flavor- ing substances of the vegetables already studied are examples of such by-products. All of the chemical changes taking ])lace in the living parts of an organi.sm are together called inetaboUsm,^ the constructive changes behig distinguished as anabolism ,- and the destructive ones as catabo- 1 Mct-ab'o-li.sm < Gr. tueta, beyond; hallcin, throw. 2 An-ab'o-lism < Gr. ana, upward. FRUIT-YEGETABLES 85 Fig. 90. — Egg Plant {Solami.m Mdonrjena, Nightshade Family, Solanaceac) . Plant in fruit, A). (Vilmorin.) — An annual; flowers similar in form to those of tomato, but violet in color; fruit dark violet, or whitish. lism.^ The forming of a carbohydrate in sunlight is called photo- synthesis.- Food-making being the peculiar task of green herbage renders foliage as a rule less useful than other parts for the storage of food. Hence we find leafy shoots accumulating food only incidentally, and then generally in largest amount where least exposed to light. The main work of foliage is to utilize sunlight for the making of food, and in so doing it keeps the surrounding air fit for animals to breathe. 37. Fruit-vegetables, as the name impHes, are succulent fruits which are used in the same manner as herbage and earth-vegetables. The most important examples are the cucumber, the various sorts of squash and pumpkin, the tomato, and the egg-plant (Figs. 80-90). To these must be added the so-called "string-beans" and "wax-beans" which are merely varieties of the kidney-bean already noticed wherein the green esculent pod plays a more important part than the unripe seeds. From the fact that they are used more as "vegetables" than as "fruits" we should expect fruit-vegetables to re- semble more nearly the former in chemical composition. We find this to be the case. In their percentage of water, 1 Cat-ab'o-lism < Gr. kata, downward. ^ Pho-to-syn'the-sis "stone" broken in half to show the single seed within. (LeMaout and Decaisne.) The plant is a tree; leaves smooth; flowers pink, ajipoaring before the leaves; fruit downy. As already intimated, the most significant features of the chemical composition of fruits are (1) the presence in con- sideralile amount of peculiar acids, (2) the predominance of sugar in the dry substance, and (3) the presence of useful salts. These chemical characteristics are shown on the chart. It will also be noticed that the proportion of proteid is very small except in the banana which, in this respect, is typical of a certain class of tropical fruits, including the date and fig, that form a highly important source of nutriment in the regions where they grow. Starch may ])e detected in the banana; in the more juicy fruits, however, starch is absent. The highly attractive flavoring matters upon which our enjoyment of fruits largely depends, are present in such ex- ceedingly small amount that chemical analysis can hardly 90 VARIOUS FOOD-PLANTS Fig. 9o. — Plum (Primus dottiestica, Rose Family, Rosace€e). Fruiting branch (Nicholson.) — The plant is a small tree with hairy twigs; flowers like those of peach but white; fruit smooth and with a bloom, the stone slightly rough. Fk ■ 96. — Sour Cherry (Pruint.s Cerasitf!, Rose Family, Rosacccc). 1 , flower- ing branch. 2, flower, cut vertically. J, fruit, cut vertically. (Wos- sidlo.) — The plant is a rather low, round-hoadcd tree with gray bark; leaves stiff' and glossy; flowers white or reddish; niostlj- in advance of the leaves; fruit smooth, light or dark red, smooth, without bloom, sour or sometimes sweet in cultivation. This species together with the niazzard cherry (P. Avium) includes most of the varieties of cherry grown for their fruit. FRUITS 91 Fig. 97. — European Raspberry (Rubus icIcBUs, Rose Family, Rosacea). 1, flowering branch and leaves. 2, flower cut vertically. 3, fruit. 4, floral diagram. (Wossidlo.) — An erect, prickly .shrub; leaflets whitish beneath; flowers white; fruit dark red, yellow, or whiti.-sh. Thi.s species together with our wild red raspberry (/?. titrigosus) which is closely similar to it, have produced our cultivated varieties. take account of them. Nevertheless their importance as an aid to digestion is beUeved to be far from insignificant. As the fruit ripens, the various flavors and acids, and. most of the attractive pigments, arise as by-products. 39. Miscellaneous food-products. Under this head we must consider the products of certain plants which ck) not properly belong to any of the foregoing groups. Thus in the common garden rhubarb or pie-plant (Fig. 112) the part commonly used is the leafstalk, just as in celery; but it can hardly be called a vegetable, for it is used quite like a fruit 92 VARIOUS FOOD-PLANTS Fig. 98, I. — Strawberry (Fragaria vesca. Rose Family, Rosacea). Plant showing manner of propagating by means of slender horizontal stem- branches, called "runners" which develop roots and shoots near their scale-like leaves. (Baillon.) — The plant is thus a perennial herb; leaves sparsely hairy, light green; flowers white; fruit red. Besides this species F. chiloensis, F. virginiana, and F. moschatn, have yielded culti- vated varieties, the first being of most importance. Fig. 98, II. — Strawberry flower, entire, and cut vertically. (Baillon.) Fio. 98, 111.— Strawberry pistil, entire, and cut vertically to show the single ovule within; and floral diagram. (Baillon.) Fui. 99. — Strawberry fruit, showing the swollen end of the flower-stalk which becomes red and fleshy and bears the ripened pistils over its surface. (Baillon.) VARIOUS FOOD-PLANTS 93 Fk;. 100. — Grapes (Vitis lahrusca and V. vinifera. Grape Family, Vitacece). A-F, northern fox grape (V. labrusca). A, flowering branch. B, flower bud, one petal (at the left) beginning to separate. C, staminate flower, with petals fallen. D, pistillate flower with rudimentary stamens. E, ovary ctit across. F, ovary, cut vertically. G-M, European grape (V. vinifera). G, flowering branch. H, bcrrj', cut vertically. ./, same, cut across. K, seeds, front view (a), back view (b). L, seed, cut across. AT, seed, cut vertically from front to back (a), and from side to side (b). (Gilg.) — Woody vines climbing by tendrils; flowers green- ish; fruit greenish, reddish, or dark purple often with a bloom. 94 VARIOUS FOOD-PLANTS Fig. 101. — Common Currant {Ribc^ nibrum, Saxifrage Family, Saxifragacew) . A, flowering branch. B, flower, cut vertically. C, floral diagram. D, bud scales. E, leaves. F, fruit cluster. O, seed, side view. H, same, cut vertically. (Baillon.) — Shrub; leaves becoming smooth; flowers yellowish-green or purplish; fruit shining, bright red, yellowish-white or striped. Includes all the cultivated varieties of red or white currants. VARIOUS FOOD-PLANTS 95 Fig. 102. — Muskmeloii (Cucumis AIclo, Gourd Family, Cucurbitarcce). Shoot showing staminate flower at a, and pistillate flower at 6. (Nichol- son.)— A long-running, annual, herbaceous vine; hairy and prickly; flowers yellow, very like those of cucumber; fruit various in size, shape, and color, mostly dull-greenish or orange. Fig. 103. — Muskmelon. Fruit, much reduced. (Baillon.) 96 VARIOUS FOOD-PLANTS Fig. 104. — Watermelon (Citntllus ruUjaris, Gourd Family, Cucurhitacece). Vine bearing leaves, flowers, and very young fruit; ,^»;; Fig. 112. — Garden rhubarb {Rheum Rhaponticum , Buckwheat Family, Polygonaceas) . Plant in flower, X ^. (Vilmorin.) — A perennial herlj; leaf-stalks often red ; flowers whitish ; fruit brown and dry. rich red tint and are ready for market. As will be seen from the chart, cacao possesses a very high nutritive value. Starch in the particularly palatal)le forms known as sago and tapioca, is obtained from certain tropical plants Avhich are especially rich in this form of food. The best sago comes principally from the spineless sago-palm, shown in Fig. 116. When full grown the tree is felled and the trunk cut into sections to facilitate the removal of the spongy pith-like interior, which is gorged with starch. By repeated washings the starch is separated from the indigestible material, and is then finally dried and granulated into small pearl-like masses for the market. A single tree will yield from four hundred to six hundred pounds of sago. Tapioca is manufactured chiefly from the large fleshy roots of the bitter cassava (Fig. 117). Curiously enough the starch in these roots is associated with a milky juice which is de- cidedly poisonous. The poison, however, is of such a nature that it entirely disappears in the process of preparation. VARIOUS F0(3D-PLANTS 105 Fig. 11.'^. — Olive {Olca europwa, Olive Family, Oleaceas). A, flowering branch. B, flower. C, corolla and stamens. D, calyx and pistil, cut vertically. E, fruit. F, same with the pulp cut through to show the "stone" within. G, seed, cut vertically between the seed-leaves. H, same, cut vertically across the seed-leaves. (Knoblauch.) — An evergreen tree or shrub, with grayish-green leaves, cream-colored, flagrant flowers, and purplish fruit. This is essentially as follows. The roots are first reduced to a pulp, and then sul^jected to pressure, which forces out the milky sap together with a large quantity of starch. After standing a while, the starch settles from this poisonous fluid. The latter is then poured off, and the starch, spread upon iron plates, is heated until all vestige of poison has disappeared, and the starch-grains becoming somewhat gummy adhere together into small irregular masses whicli constitute the tapioca of commerce. A seaweed known as carrageen or "Irish moss" (Fig. 118), found along the North Atlantic coast on both sides of the 106 VARIOUS FOOD-PLANTS Fig. 114. — Sugar-cane (Saccliaruin officinarinn. Grass Family, Gramrncce). Plant in flower. A, part of spike, showing long silky hairs. B, spikelet detached. C, flower, showing stamens, pistil and lodicules at the base. (Bcntley and Trimen.) — Perennial, attaining a height of 4 m.; stem variously colored, 2-5 cm. thick. MISCELLANEOUS FOOD-PRODUCTS 107 •"^^ Fig. 115, I. — Cacao {Thcohroma Cacao, Silk-C'iittun Family, Stcrculiacew) . The plant is a tree 3-13 m. tall, with shining leaves, and brownish-red flowers which spring from the trunk and older branches, and produce yellowish, orange, or brownish fruits, somewhat resembling a squash. (Baillon.) ocean, i.s used for food, generally in a sort of pudding, some- what as tapioca. The whole plant is cooked, after having being dried and bleached in the sun at the time of gathering. The principal chemical constituent (see chart) is a mucilagi- nous carbohydrate which swells greatly in water and gives to Irish moss blanc-mange its jelly-like character. Finally must be mentioned as widely cultivated for food the common field mushroom (Fig. 119) which, as the chart will show, compares favorably with many vegetables in the percentage of nutritious constituents. The statement is frequently made, however, by writers who ought to be better 108 VARIOUS FOOD-PLANTS II Fig. 115, II. — Cacau. Loaf. Flower, complete. Same with petals removed. A petal detached. A stamen, showing the four-celled anther. Pistil. Seed. (Baillon.) Fig. 115, III. — Cacao flower, complete. (Baillon.) Fig. 115, IV. — Cacao flower, cut vertically. (Baillon.) Fig. 115, V. — Cacao. Seed, side view. Same, cut vertically, showing a wrinkled seed-leaf. Diagram of flower. (Baillon.) MISCELLANEOUS FOOD-PRODUCTS 109 ■^ija^-^^Sax.^ Fig. 116, I. — Priokly 8ago Palm {Metroxylon Rumphii, Palm Family, PulmacecE). Tree about 10 m. tall or less; leaves very long and plume- like, prickly at base; flowers numerous, imperfect, on large special branches; fruit covered with hard woody scales. (De Colange.) Fig. 116, II. — Smooth Sago Palm {Metroxylon lave. Palm Family, Fulnta- cece). K, tip of a flower-cluster branch. L, stamens on corolla of a staminate flower. M, pistil cut vertically, showing ovules and young scales. N, fruit cut vertically to show the seed surrounded by dry flesh and woody scales. (Blume.) — The plant is similar to the prickly sago palm but larger and without prickles. no VARIOUS FOOD-PLANTS Fig. 116, III. — Prickly Sago Palm. Ripe fruit and remains of a staminate branch of the flower-cluster. (LeMaout and Decaisne.) — Three yeais are required to ripen this strangely armored fruit. Fig. 117, I. — Bitter Cassava (Manihot utilissima. Spurge Family, Euphor- biaccw). A shrub 2-3 m. tall, producing swollen roots weighing 10 kg. or more; flowers staminate and pistillate on the same plant; fruit dry, breaking apart. (Pax.) MISCELLANEOUS FOOD-PRODUCTS 111 Fig. 117, II. — Bitter Cassava. A, flowering and fruiting branch. B, stani- inate flower, cut vertically. C, pistillate flower, cut vertically-. D, fruit. E, F, G, seed, viewed from front, back, and side. H, starch grains from the root, much magnified. (Pax, Martins, and Tschirch.) informed, that mushrooms are as nourishing a food as meat. That this is an absurd exaggeration is seen from the fact that a pound of mushrooms contains less than one-sixth as much proteid as a pound of meat. Furthermore it has been ascer- tained that while the proteid of meat is almost entirely diges- tible, scarcely more than half of the proteid in mushrooms is available as nutriment. Still, mushrooms are sufficiently nu- tritious to warrrant our using them much more than we do, especially certain wild forms which abound in our fields and woods, and of which some at least are preferable even to the cultivated species. The reason these wild forms are allowed to go to waste, is chiefly that there grow along with them cer- tain poisonous species so nearly similar in appearance to the edible sorts as to have led ignorant persons to gather and eat them unwittingly, ^\'ith fatal result; for unhke the poison in cassava root, that in poisonous mushrooms is not rendered 112 VARIOUS FOOD-PLANTS Fig. 118. — Carrageen (Chondrus crispus. Carrageen Family, Gigartinacca.) Various forms of the seaweed, about natural size, the form a showing the "fruit" as oval masses embedded in the branches. The whole plant is dark red or purplish when alive. (Luerssen.) harmless by cooking. Unless one is well acquainted with the peculiarities by which edible and poisonous sorts may at once be distinguished, it is surely both fooHsh and dangerous to gather wild mushrooms to eat ; nevertheless, such knowledge is not difficult to acquire with the aid of good pictures and careful descriptions, and to those who spend much time in the country the information may be of not a little value. On the subject of poisonous plants Ave shall have more to say in a subsequent chapter. The only safe rule is for a person to avoid touching, and on no account to eat, any part of a plant which he does not surely recoqnize and know to he harm- VEGETABLE FOODS IN GENERAL 113 Fig. 119. — Field Mu.shroom (Aoaricus campestri^i, Giil-niushroom Family, Agaricacece) . Fruit-bodies, natural size, in various stages of growth. a, "button stage," in which the regions of stalk and cap are just dis- tinguishable; b, a somewhat later stage, cut vertically to show the "gills" just appearing below the cap; c, a still later stage, similarly cut, in which the gills now fully formed are yet protected below by the membranous '"veil"; d, stage in which the cap is almost expanded, showing on its under side the veil partly torn from the edge and ex- posing the pink gills; e, final stage in which the cap is fully expanded, and the veil, now entirely free from the rim, remains only as a ring around the stalk. (Luerssen.) — The gills, at first pink, turn finally dark purplish brown, owing to the formation upon them of dark dust- .* like "spores" which fall from the exposed gills, are carried away by the wind, and give rise to new plants when favorably placed upon well- i manured ground. These spores first produce a network of threads which feed upon the decaying materials, and finally send up the fruit- bodies above the surface. less. Every summer brings the sad news of children and older persons horribly poisoned through ignorance of our common- est 'plants. In a large proportion of these cases the plant eaten has been one which was thought to be harmless be- cause it somewhat resembled a cultivated species or was mistaken for some harmless wild plant that is commonly eaten. Hence it should be remembered that, even though a wild plant looks like a familiar garden vegetable, there may be danger in eating or chewing any part of it. 40. Vegetable foods in general. In the foregoing sec- 114 VARIOUS FOOD-PLANTS tions, it lias been .sliown that a classification of vegeta]:)le foods bas(>(l upon the manner and degree of their usefuhiess is at the same time a fairly accurate grouping according to chemical peculiarities, the reason being that their use depends largely upon their composition. Guided by this principle we may now profitably compare vegetable foods with those of animal origin, so as to gain a better apprecia- tion of their relative value in supplying human needs. A satisfactory understanding of the uses of food-plants clearly involves the study of this larger question. 41. Food as fuel and building material. Before proceeding to compare vegetal )le with animal foods certain fundamental facts regarding food in general must be considered. We know that so long as a man is alive and active, the parts of his body are wearing out from daily use, and he is losing heat. If deprived of food, his weight and strength decrease, while, on the other hand, if he is properly fed, nutritive materials become incorporated with the various parts of his body as fast as these wear away, and he finds his strength kept up by a constant supply of energy. Were it possible to conceive of a steam-engine Avhich could derive from the fuel it con- sumes not only heat and power but also material to replace that used up in action, we should have a machine to which we might liken the human body in its use of food. If we could imagine, furthermore, a small locomotive able to do all this, and also to increase the size of its parts by the addi- tion of extra material, so as to grow into a large locomotive, such a marvelously endowed machine, would be very like the body of a child. Thus we see that food answers the double purpose of supplj'ing us with building material and with fuel. But as alreadj- intimated in the last chapter, proteids, fats, and carbohydrates are not equally useful as sources of substance and energy. As the chief wear in our bodies comes upon the muscles and other parts that are composed largely of nitrogen, and as neither fats nor carbohydrates contain this element, it follows that proteids, being nitrogenous, must be of the first importance as furnishing building material. This enables us to understand why it is that an animal deprived entirely ^! I -=_- o o 0 0 1 z; - ■''■ 7 -1 •^ " ■'• 5^ r Z -. E - = - .-: i; '; - '/^ ' ^ " X, — ^^ -- -^ — — ■^ - — - E L- E i^ _ E = ^ = _ - -X ^ — — r:~ — ' :_— -* — '^ - ■ '- -^ :_ — - - — -^ __ -T-r — -- - - - ^;- ■ 1 'o ° =! f: ~ — _ _ - •-- 7 - " :" - - — - - - -- ::^ :^ , ._. - _. — ' — = -_ :- _- . '- — - e: • - _ E IS — - - - ■^ ':■ -- — t- -.^ .= ' - 1 ■ ;'. J: = lH- 1. ". — - r-,0 — — - - - 1 — — — -- - - - - ~ , . ■ ■ ■ — — — 1 1 =: ^ E = '- -- E ~ ^ i I = 2 E 5 L- - -: ■_ = = = - o o _- — — — : r_ — - _ ■"^F = = = = f= =; i : _ = E = E E P ^ = E 1- E r - - E = E ; 1 :r - E= =; — — — — - - =3 - i 0 ? — - = t: = = t= 1 s. ■.; I ;- =: :- r = = E z^ E = =; E ^ - :^ E - ;|; = = E E = E E E E E E E = E =: E -- ; (-1 0 i ^ E = E = E E EJ - -- - 7 E E " ; ^ E S z = = E E E ;e = E = E E : E E : = 1 1 = = i ^ i =. ~ 1 : = : o 0 0 = 1 ~ 1 i 1 = = = — - - ^ - ^ E T - -• -i 0 E ~ 1 % i = N = = E '^ f r 7" E E - ^ ^ B ll|;! if p= ^ I 7 ^ ^ ^ E z o 0 1 ~ i •S ■a 0 0 u. e - - z : - - - - - - - - It is of course as.sumed that the rations inchide a sufficient quantity of water and of salts. '^ Physiologists formerly estimated the daily need of nitrogen at twenty grams, but recent experiments indicate that ten grams is amply sufficient. 116 VARIOUS FOOD-PLANTS indicated. When we were considering the amount of any substance in a given food, we were able to express tlie facts with perfect dcf- initeness because we were deaUng with what could be n^easured by weight and vokunc, and because we had the units (gram and cubic centimeter) by which the measurements could be expressed. Al- though neither heat nor mechanical force have weight or volume, they may nevertheless be measured as to their amount by means of suitable units. Such a unit for heat is the amount required to raise the temperature of one kilogram of water one degree of the centigrade thermometer. This amount of heat is termed a Calory. ^ From very careful experiments it has been calculated that if by means of a steam-engine, one Calory obtained from fuel could be entirely converted into mechanical energ}', this would be sufficient to lift a weight of 424 kilograms, 1 meter, or 1 kilogram, 424 meters. The energy required to lift 1 kilogram, 1 meter, being called a kilo- grammeter, we thus have in the expression 1 Calory— 4^4 kilogram- meters, what is known as the "mechanical equivalent of heat." 43. Energy of vegetable foods. Experiments show that if com- pletely burned, 1 gram of fat yields 9.3 Calories " " "carbohydrate " 4.1 " " "proteid " 4.1 These figures also indicate approximately the amount of energy which would be obtained from equal quantities of the same sub- stances consumed in the human body. To estimate, therefore, the amount of energy obtainable from 100 grams of any food of which we know the chemical composition, we have only to multiply the percentage of each nutrient by the number of Calorics yielded by a single gram, and add the products thus obtained. This has been done for the vegetable foods of which the composition is given in the chemical chart (Fig. 120); and the number of Calories is indicated by heavy lines having lengths proportionate to the amount of energy yielded by the foods they represent. Foods which yield much energy are commonly described as being "hearty": the lines in the chart may be said therefore to indicate the relative "hearti- ness" or fuel- value of common vegetable foods. But it may be asked, Does a fat and a carbohydrate serve us in exactly the same way? Physiologists tell us that either may replace the other in our food, provided the amounts eaten represent an equivalent number of Calories; but there is this difference that, whereas carbohydrates (which, so far as they are digestible, enter the blood as sugar) are immediately after digestion available as a source of heat and muscular energy, fats require to undergo some ]")reliminarv transformation in the body, before they can be used, and are therefore less serviceable for immediate needs. Fat, how- 1 Cal'o-ry < L. caZor, heat. RATIONS 117 ever, since it contains so much more energy than ghicose in i)r()j)or- tion to its bulk, is particularly well adapted for storage in our bodies as reserve material; and what is absorbed from our food needs to undergo scarcel.y any change before being laid away. These differences in usefulness between fats and carbohydrates have been well expressed l;),y comparing the latter to ready cash, and the former to money in a savings bank. This helps us to under- stand the benefit wliich pedestrians and bicyclists derive from the use of sweet chocolate. The large proportion of sugar (about 50%) yields up its energy immediately in time of need, while the consider- able proteid offers material for the repair of muscular loss, and the abundant oil remains as a more slowly available reserve. Likewise, the special craving which young people have for sweets, receives at once its explanation and justification when we remember the extraordinary activity which belongs properly to their period of life. It needs to be pointed out, however, that the quantity of carbohjTlrate eaten should be strictly proportioned to the amount of bodily activity; for otherwise there will be left in the system an excess of sugar, which may either go to produce an unhealthy accumulation of fat, or by undergoing acid decomposition, seriously disorder the digestive organs. Too much sweet food and too little exercise is one of the commonest causes of indigestion and obesity. 44. Rations. Recent experiments indicate that the needs of an average man would be fully met by a daily ration of 300 grams of carbohydrate, 50 grams of fat, and 50 grams of proteid.^ This gives of nitrogenous material sufficient to cover an average daily loss of about S grams of nitrogen, and of carbonaceous fuel ' More or less variation from the above figures would of course be required to meet the needs of different ages, sexes, constitutions, and occupations. A discussion of such details cannot well be undertaken in this place. It should be said, however, that physiologists of the highest standing now admit that former estimates of the body's needs based upon records of the amount commonly consumed are too high for maximum efficiency. The stantlard which has been most generally adopted by American writers on nutrition calls for 12.5 grams of proteid, with sufficient fat and carbohydrate to yield a total of 3,500 Calories as the daily ration for a man at moderate muscular work. These figures were derived mainly from observation of what many healthy Americans actually eat, and are admittedly but rough approximations erring rather on the side of excess than deficiency. Good health is undoubtedly maintained on such an allowance, but this, of course, is no proof that eating somewhat less would not conduce to even better health and greater vigor. A very liberal allowance would be 400 grams of carbohydrate, and 100 grams each of fat and proteid for an average man. 118 VARIOUS FOOD-PLANTS enough to yield about 1,000 Calories or 805,600 kilogrammeters of energy, which has been found-to be approximately tlie amount ex- pended in 24 hours. If at first sight this seems to be an exaggerated estimate of the energy given out, it should be borne in mind that a very large share goes to keep up the warmth of the Ijody; while of the remainder wdiich is transformed into mechanical activity, a considerable proportion is used up in the muscular movements of the digestive organs, in breathing some 23,000 times, and in mak- ing more than 600,000 heart-beats, thus leaving only about one third of the whole available for locomotion and external work. The main point which here concerns us regarding the make-up of a proper daily ration is the relative proportion of nutrients rather than their absolute amount. On the basis of the figures given, it may be stated roughly and in a general way that 1 part proteid, 1 part fat, and 6 parts carbohydrate, would ordinarily meet the daily needs of an average person, or in other words that one's food should be about | proteid, i fat and f carbohydrate. In the rations recommended it is assumed that the foods chosen are easily digestible; for it is not what we eat but what we digest that nourishes us. For students and other brain-workers digestibility is of es- pecial importance since their largely sedentary life leaves them but little surplus energy to spare for unnecessary digestive work. A glance at the chemical chart (Fig. 120) will show that many vegetable foods do not have their nutritive constit- uents in anything like the standard proportion. This means that if a man were to obtain all his nourishment from such foods, he would have to eat too much of one ingredient (generally a carbohydrate) in order to get enough of another. When it is remembered that the dry substance of meats, fish, eggs, and other such foods of animal origin, consists almost entirely of proteids and fats, we see that here also there is a similar disproportion, although in another direction. Since, however, the constituents which are deficient on the one side, are in excess on the other, a mixed diet combining animal with vegetable foods, is most likely to be well-balanced. From this point of view it is interesting to notice how generally the instincts of mankind have led them to prefer combinations of food wherein the comjoonents supplement RATIONS 119 each other, and thus approximate to the chemical ideal. The appropriateness of coml)ining bread and butter we have already had occasion to notice. Similarly in "crackers and cheese," "mush and milk," "eggs on toast," "meat and potatoes," and many other favorite combinations which will readily occur to the reader, we have the animal part poor in carbohydrate and rich in fat and proteid, supplemented by a vegetable food comparatively poor in these latter ingredi- ents, but rich in sugar or starch. Sometimes, indeed, as in "pork and beans" we may have a highly valued combination in which not only the carbohydrate but also nearly all the proteid is furnished by the vegetable part, the animal por- tion being little else than fat; or, as in certain salads, we may have the fat represented almost entirely by olive-oil. Those who prefer for any reason to abstain entirely from meat or other animal food may find adequate substitutes in various seed foods of highly nitrogenous composition, as the table clearly shows, provided the greater difficulty of digesting them does not offset their advantages, as is often the case with persons of sedentary habit. The recent military triumphs of the Japanese show in a striking way what hard physical work can be done on a diet consisting in very large part of rice. In most cases, however, it will be found that the vegetable foods are of value to us chiefly as contributing carbohydrates, and thereby supplying the most marked deficiency of foods derived from animals. We have now an answer to our question regarding the special nutritive value of vegetable as opposed to animal foods. Both, as we know, yield us building material and fuel; and either the one or the other sort of food is used almost or quite exclusively by certain races of mankind, just as by herbivorous or carnivorous animals; and, furthermore, we have seen that whatever nourishes the animal kingdom, including ourselves, must be derived ultimately from plants. Nevertheless, the teachings of chemistry and the practice of the best-fed and most vigorous peoples agree in showing that while it ma}' ])e desirable for us to depend mainly upon animal food for our nitrogenous materials and carl)onaceous reserve, it is to vegetable foods that we must look to supply Bo o O Si o n o 33 'r. OJ c G cc 0) <1i 0' t; fl fl tc " "oJ c o C !^ ,9 C o 15 cli Ph c-i <; =5 <; <3l ? O g >> e ri C 1— ( 03 o C-i ID S3 o o O CJ 3 J= pqp^OK mu ii o o o u 'C 'C 'Jh 'E 'C o o o p ^ o w — -;^ WW — =;-;^ -^ ~ ~ ,^ §'~ S -i «■"" S Si""'""" S:i . .Si '" . p '" '^ *" 'f . *r^ *" "-r* "-^ "-^ •"* '^ '^ '^ p^ r',"^ ri "^ ' O "^ * f :j ' c__' ""^ ""^ ""^ CJ) V "^ CJ "^ o .'§ o o o g .^ .| J .1 .| g ^ ^ ■ .:; o •-T3 300 ^xH^Z I? c 5 !^-K.S 3-0 « . o3' fl 0) O s- I ' ■^■^•■=:^^ K O f- '^ ZU§ C o HO^iS-y^ •5< v3 CJ jS .>W CO cc ;^ w %< c3 C •3,1/: W 5 O c3 St: 3-2 OS S ^ £ -2 S ?- O GO.— ~ =- ^ w 2 >. ^ 5J ■^J^i- % c •/3 0 0 ^ Lh •n s p CT -J ^^ »r; Cm O* r c u 7J c s c c ^ c3 ^ q .■& ^ ;^ ?^ C"? S c =.■§.■= 3 bs"!-! i'i"f-lii-=|i-IJI-|J^I|oi *3oui;?2e^Hadu6fS6u ?; c ;ii z c ^ ^ c hj g g -i^ i g S !o-3 5 S 2 c ~ £ 2- S § rt c.S ^;= S u g -^ 2 ^ '^^^ ^^l§ > ., 1» IK' li bi'^ 03 .:i 122 VARIOUS FOOD-PLANTS us with energy which shall be immediately available at any niouiont for the work of life. 45. Food-plants in general. When considering the cereal grains, we found that important facts regarding their special value and present use were explained by the original geo- graphical range and economic history of the species. AVe have now to conclude our study of food-plants by a com- parison, from this point of view, of the other kinds with these, so that we may arrive at some further general ideas concerning them. In the tabular view on pages 120-121 is given for each of the species already referred to, a brief statement of its native home and period of earliest cultivation, according to the opinion of recent authorities. Where these are doubtful an interrogation mark in parenthesis has been placed after the point in question. 46. The primitive centers of agriculture. We have al- ready seen that the three grains, wheat, rice, and maize, which have played a supremely important part in the history of mankind, are each native to a region which is widely separ- ated from the homes of the other two, — wheat being in- digenous to Mesopotamia, rice to southeastern Asia, and maize to tropical America. There is abundant evidence to show that it was in these regions, and in the lands immediately adjacent, that agri- culture was first systematically pursued, and thus made pos- sible the development of the great civilizations of antiquity. It is certainly a fact of profound significance in human history that wheat, the most valuable of the grains, should be native to a region so near the junction of the three continents of the eastern hemisphere. Antiquarian scholars are of the opinion that from the fertile valley of the Tigris and Eu- phrates as a center, agriculture, with the civilization which it implies, extended to all the great peoples of Africa, Europe, and southern and western Asia. A more restricted civiliza- tion of later development and less importance was that which arose in the valley of tlu^ lioangho and Yangtse-Kiang, and formed the beginning of the present Chinese Empire. Still later, although many centuries before the coming of Colum- CULTURE-PERIOD AND NATIVE HOME 123 Fig. 121. — Map showing, by shaded areas, the three primitive centers of agriculture. bus, an important agricultural center was established on the highlands of tropical America, and formed the basis of those remarkable civilizations of the Nahuas and Incas which the Spanish invaders overthrew. These three primitive centers of agriculture (Fig. 121) are important for us to remember, since, when taken in con- nection with what is known of the native homes of cultivated ])lants, they help us to understand why certain species have been cultivated so much longer than others, and why they have come to be so important. 47. Relation between culture-period and native home. It may be laid down as a rule that, other things being equal, the nearer the native home of a cultivated species is to the region forming one of the primitive centers of agriculture, the longer has that species been under cultivation; and, conversely, the more remote its native home from an agri- cultural center, the more recently has it come to be cultivated. This, indeed, is what we should expect in view of the probable beginnings of agriculture already considered in our study of the grains (section 17). Reference to the foregoing tabular view will afford some interesting confirmations of this general principle, which in turn will help us to an orderly (and there- 124 VARIOUS FOOD-PLANTS fore more easily rememliered) arrangement of the facts in our minds. Let us first consider the plants which were cultivated in ancient or in prehistoric times. As used in the tabular view the term prehistoric indicates, for plants of the Old World, a cultivation of over four thousand years, or in the New World of over two thousand years : ancient, means over two thousand j-ears for Old World plants, or for New World species, a cultivation for more than five hundred years, or in some cases for over one thousand years. That is to say, the cultivation of the plants designated as prehistoric or ancient, preceded or was associated with the earliest civiliza- tions of the hemisphere to which the}' belonged. With refer- ence to their native homes we find that these plants fall readily into the following groups : — L The Meditcrranemi Group: plants of which the native range fell within, or was adjacent to, the region about the eastern end of the Mediterranean sea — the region wherein were developed the great Eurasian civilizations of antiquity, from which our own is principally derived. The plants in- cluded are wheat, barley, oats, rye, chestnut, filbert, walnut, almond, pea, beet, turnip, carrot, parsnip, onion, asparagus, cabbage, spinach, lettuce, celery, cucumber, egg-plant, apple, pear, quince, plum, common cherry, European grape, musk- melon, watermelon, lemon, banana, date, fig, and olive. IL The Oriental Group: plants having their native home extending within or adjacent to the valleys of the Yangtse- Kiang and Hoangho, the seat of the most ancient of oriental civihzations. Under this head come rice, radish (?), peach, orange, and sugar-cane. in. The American Group: plants indigenous to the high- lands of tropical America or in lands adjacent thereto, that is, within or near the region occupied by the ancient civiliza- tions of the Western Hemisphere. This group includes maize, peanut, coconut, kidney-bean, Lima bean, sweet potato, white potato, pumpkins and squashes, tomato, pineapple, cacao, and bitter cassava. The plants which are indicated as of modern culture are believed not to have been cultivated bv the ancients of the CULTURE PERIOD AND NATIVE HOME 125 Old ^^'orkl before the beginning of the Christian Era, or in the case of New World forms, to have been in cultivation, at most only a few centuries before Columbus discovered America. By plants of recent culture are to be understood such as have been introduced into agriculture since the discov- ery of America. A glance at the tabular view will show that none of these '' modern " or " recent " plants are native to regions within or near to the primitive centers of agriculture. Some of these plants occur wild in both the Old and the New World; namely, raspberries, the garden currant, and the field mushroom. Those confined to the Old World are buckwheat, rhubarb, and sago: those of the New World are the butter- nut, hickory, pecan-nut, Jerusalem artichoke, garden straw- berry, and northern fox-grape. The Brazil-nut and "carrageen" are the only other food- plants included in our list. Of these the wild product so fully satisfies the demand, that the plants have never been cultivated, and their native homes are thus without special significance in the matter under consideration. It is, how- ever, a confirmation of the principle ahove stated, that no plant of any considerable agricultural importance has been derived from regions Avhich are remote from the primitive centers of agriculture, or cut off from early communication with them, even though the climate may be highly favorable. This is true of South Africa, Australia, and New Zealand. The facts we have stated show plainly that the native home of a cultivated food-plant stands in close relation Avith its importance to mankind. That is to say, just as we found that a knowledge of the chemical composition of plant-foods enabled us to understand in what manner and how much they were used, so now it appears that to know the original geographical ranges of cultivated plants helps us to explain the time and area over which their use has extended. Of course, many other considerations often need to be taken into account in order satisfactorily to explain all that is known regarding the differences in extent and duration of such usefulness. What should be insisted upon is that geo- graphical facts are of fundamental importance in discussing the economic history of food-plants. 126 VARIOUS FOOD-PLANTS 48. The multiplication of varieties. Besides the effect which geographical range has exerted upon the spread and period of cultivation, the differences in the number of varie- ties that have arisen through human agency among culti- vated plants may be attributed largely to the same important factor; since, as may be readily shown, the number of varie- ties in a given species is much influenced by the extent and duration of its culture. For, taken as a whole, the plants of ancient or prehistoric cultivation, as compared with those of modern or recent introduction, present a marked contrast in the greater number of clifTerent varieties which have come to be cultivated. Thus we have the common buckwheat, a "modern" plant, without any well-marked varieties, as against the "ancient" oats and rye, each with several varie- ties; and the "prehistoric" wheat, barley, rice, and maize, with scores or hundreds of varieties. If the comparison of the newer with the older be extended to nuts, vegetables, and fruits, a similar rule will be found to obtain; although it is true that more or less important exceptions will be encoun- tered. These exceptions go to show that other elements besides time of culture would have to be taken into account in any attempt to explain fully why one cultivated species should have more or less varieties than another. But these other factors need not be here considered, since our present purpose is to point out that just as the area of use and the culture-period of a plant have been dependent largely upon the geographical relation of its native home to a primitive center of agriculture, so upon these factors, in their turn, have largely depended the number of varieties which have been artifically developed. 49. How varieties arise. Finally, a brief consideration of how such "artificial" varieties arise, will help us to under- stand why it is that long and widespread cultivation should tend to increase the number of these varieties. It will be remembered that when discussing what is meant by a "va- riety" as distinguished from a "species" (section 9) the state- ment was made that no two individual plants are exactly alike even though raised from seeds of the same parent. Sometimes the differences are verj'- noticeable, and may af- ARTIFICIAL SELECTION 127 feet the plant as a whole, or any j)art, with reference to size, form, flavor, proportion of chemical constituents, time of appearance or ripening, hardiness, and so on. Since in plants which are raised from seed, the special peculiarities of the parent are found to reappear in its offspring to a greater or less degree, it becomes possible for the farmer to preserve in future crops the peculiarities which please him, b}'^ taking his seeds from those individual plants which satisfy him best. Thus if early ripening is the quality desired, the earliest seeds are the ones chosen year after year, until in the course of several, or it may be many generations, furnishing earlier and earlier plants, the offspring finally produced from these selected seeds are found to ripen their product so much sooner than any other sorts that they are recognized as a new variety. With many plants, such as strawberries, the seedlings are apt to vary so widely from the parent and from each other that the varieties are said to. be "not true to seed": and in these cases it is the practice w^hen once a seedling possessed of desirable qualities has been obtained, to propagate it by means of "cuttings" or similar detached portions of the parent plant instead of by seed. Occasionally important differences appear among the in- dividuals raised from cuttings or the like, and these may similarly form the basis of new varieties. 50. Artificial selection. Besides these principal ways in which cultivated varieties arise, there are some others the consideration of which must be deferred to a later chapter. What at present concerns us is the general truth that to a very large extent human or artificial selection exerts a control- ling influence either upon the development or the perpetua- tion of varieties, and frequently upon both. Since the longer and more widespread the cultivation of a given plant has been, the more extensive and more varied must have been this influence, we should expect in general that the number of varieties of a cultivated plant would be proportional to the time and area of its cultivation; and this expectation we find to be justified by the facts. CHAPTER IV FLAVORING AND BEVERAGE PLANTS 51. Food-adjuncts. If by "food" we mean whatever is eaten to supply the building materials or energy needed by the bod}^, it must follow that much of what is eaten is not food. Various substances, such as pepper, sage, caraway, horserachsh, and vanilla, or beverages, like tea or "wnne, are taken with food for an entirely chfTerent purpose; namely, for their flavor or stimulating effect, and scarcely, if at all, as nutriment. Such materials may be distinguished, there- fore, as food-adjuncts. The flavoring materials included un- der this head may be conveniently grouped as spices, savory herbs, savory seeds, miscellaneous condiments, and essences. 52. Spices are aromatic substances derived from hard or hardened parts of plants and used commonly in a pulverized state. For example, cloves (Fig. 122) are flower buds hard- ened by drying; allspice (Fig. 12,3), black pepper (Fig. 124), and red pepper (Figs. 125, 126) are dried berry-like fruits; mustard (Figs. 127, 128) is a seed; nutmeg (Fig. 129) is also a seed, and mace the fleshy network (dried) which sur- rounds it; cinnamon (Fig. 130) is the young bark of a tree; while ginger (Fig. 131) is a root-hke stem which grows under ground. The peculiar aroma of a spice is in general due to the pres- ence of a volatile oil. Volatile oils bear a certain resemblance to the fixed oils, but differ from them in that they evaporate when exposed to the air, leave no greasy stain on paper, and all dissolve readily in cold alcohol. On account of the volatile nature of their flavoring constituent spices lose aroma when exposed to the air, especially after they have been ground. Advantage is often taken of the ready evaporation of vola- tile oils to separate them by distillation. This process is essen- 128 SPICES 129 Fio. 122. — Clove (Jambosu Caryophylluti, Isiyrtle Family, Myrtnccce). A, branch bearing leaves, flower buds, and expanded flowers. B, a flower bud (such as form when dried the "cloves" of commerce) cut length- wise to show the inner floral parts and the minute cavities near the surface containing the volatile "oil of cloves." C, petal sho'W'ing oil cavities. D, stamen, a, front; b. back; c, side. E, pollen grain, a and b, difi'erent views, much magnified. F. fruit. G, seed cut across. H, embryo removed, side view. /, same with one seed-leaf removed, to show the seed-stem within. (Niedenzu.) — The plant is an exception- ally beautiful evergreen tree of pyramidal form 9-12 m. tall, with smooth grayish bark, thick glossy leaves containing numerous cavities like those of the flower, and filled with a similar fragrant oil which perfumes the air around; flowers and flower-buds rosy red, highly fragrant, produced through the year; fruit fleshy, grayish brown. Native home, Molucca Islands. In use from ancient times in the East. tially as follows. The material to be distilled — say some clove spice — is heated in a vessel tightly closed except that from the top comes off a long tube which passes finally through cold water. The volatile oil, after being driven off as vapor by the heat, is changed back to a liquid upon being chilled. Sometimes the substance to be distilled is mixed with water, and in that case the volatile oil passes off with the steam. Both are condensed together, and flow from the chilled tube as a mixture of oil and water. These two substances readily separate, however, since neither will dissolve the other more than slightly, and the oil will either sink (as oil of cloves and a few others) or float. Most volatile oils form films of peculiar form and often 130 FLAVORING AND BEVERAGE PLANTS Fig. 123. — Allspice (Pimento officinalis. Myrtle Family, Myrtuccce). G, flowering branch. /•', flower, lower part cut vertically. H, fruit, cut vertically, showing Ijut one seed developed and this with a cur\^ed embryo which nearly fills the fruit, in the wall of which are numerous minute volatile oil cavities. (Niedenzu.) — Tree 10 m. or more in height with leathery aromatic leaves black-dotted beneath; flowers white; fruit fleshy, containing one or two seeds. Native to the West Indies and Central America, where they are often planted in rows called "pimento walks." beautiful color when a single drop is let fall upon a broad surface of perfectly clean water. The curious shapes assumed by the films are called cohesion figures. The amount of volatile oil present in a spice is often ex- ceedingly small, even when the aroma is strong. Ginger and black pepper have each al)out 1-2%; allspice 3-4.5%; nut- meg 2-8%. Cloves are remarkable in having 18% of volatile oil. Oil of cloves is well knoAvn as a powerful drug, as is also the volatile oil of cinnamon. If taken in considerable quan- tities they act as poisons. The volatile oil of nutmeg is simi- larly poisonous if taken in more than small amounts. It is SPICES 131 Fig. 124. — Black Pepper {Piper nigrum, Pepper Family, Piperacece). A, fruiting branch, J. B, part of a spike showing three flowers, t- C, fruit, cut vertically to show the seed within, its minute embryo in copious seed-food, f. (Baillon.) — A woody vine, tall-climbing partlj^ by means of roots; leaves evergreen; flowers minute; fruit red. Native home, India. Fig. 125, I. — Red Pepper {Capnicum annuum, Nightshade Family, Solatta- cece). Fruiting plant, i. (Vilmorin.) — An annual or biennial herb of shrubby appearance; leaves smooth; flowers whitish; fruit juiccless, red, yellow, or violet, very various in form and color. Native home, South America. 132 FLAVORING AND BEVERAGE PLANTS Fig. 125, II. — Red Pepper. Fruiting branch of the "Chili pepper," (Vilmorin.) Fiu. 12(). — Red Pepper. Flower, cut vertieally, enlarged. Fruit c^ut across near the top and near the base showing the single cavity above be- coming two cavities below; about natural size. Seed, cut vertically, enlarged. (Redrawn from Berg and Schmidt.) SPICES 133 Fig. 127. — Black Mustard (Brassica nigra. Mustard Family, Cruciferce). Plant in flower and fruit, reduced. Pod. Seed, cut across showing the embryo with seed-leaves folded around the seed-stem, enlarged. (Britton and Brown.) — Annual, sometimes attaining a height of over 2 m.; leaves becoming smooth; flowers bright yellow; pods smooth; seeds dark brown. Native home, north temperate regions of Old World. Fig. 128. — White Mustard (Sinapis alba, Mustard Family, Cruciferce). Stem with leaves. Top showing flowers and fniit, reduced. Pod, about natural size. (Britton and Brown.) — Plant an annual about 30-60 cm. tall; leaves hairy; flowers yellow; pod bristly; seeds light • brown. Native home, temperate regions of Eurasia, and Northern Africa. reported that the excessive use of this spice in India has re- sulted in dangerous, almost fatal consequences. In the small amounts necessary to give a mild and pleasant flavor to food all the spices in common use are not only wholesome to most persons but may be aids to digestion. Highly spiced food or strongly flavored confectionery, on the contrary, is apt to be unwholesome if much l^e eaten, and for young people positively injurious. It is a curious fact that the volatile oil to which mixed mustard owes its aroma and pungency does not exist in the seed itself, but is formed, during the process of mixing, from a tasteless substance through the action of an enzyme. Like diastase this enzyme acts only in the presence of moisture, and is destro3'ed by a temperature of 100° C. Hence, if dry mustard be sifted into boiling water no pungency is developed. 134 FLAVORING AND BEVERAGE PLANTS Fig. 129. — Nutmeg (Myristica fragrans. Nutmeg Family, Myristicaccce). A, fruiting branch .showing a ripe fruit with pulp opening to let out the mace-covered seed, %. B, stamens, enlarged. C, pistillate flower cut vertically, 5. p, perianth; g, pistil containing a single o\njle. D, seed surrounded by the net-like "mace" (a). E, same, cut vertically to show the aril (o), the seed-coat (s), the seed-food (looking as if it had been chewed and hence described as "ruminate"), and the em- bryo (e). (Luerssen, Baillon.) — The plant is a tree attaining 20 m. in height; leaves evergreen; flowers pale yellowish; fruit dull orange color,' downy, the pulp splitting open at maturity; se(>d brown, enveloped by a blood-red aril which like the seed is aromatic. Native home, Moluccas. Certain of the spices contain in addition to their volatile oil a considerable amount of fixed oil which may be readily expressed from them. Black mustard seeds contain 15-25% of fixed oil, white mustard 25-35'^^^, and nutmeg 25-30%. In the manufacture of table mustard the fixed oil is commonly removed from the ground seeds by pressure. It resembles olive-oil, and is used in much the same ways. ^Mnle, as we have seen, the peculiar aroma of ginger and SPICES 135 Fiu. 130, I. — Cinnamon {Cinnamomum. zexjlanicum. Laurel Family, Laura- cece). Leafy branch with flowers and fruit. (Baillon.) — A tree attain- ing about 10 m. with thick rough bark, and young branches prettily specl-ded with dark green and light orange; leaves leathery, shining, evergreen; flowers whitish, of disagrecaljle odor; fruit a white-spotted purplish-brown berry. Although volatile oil is found in various parts of the plant no odor is perceptible at a short distance. Native home, Ceylon, India. Ficj. 130, II. — Cinnamon. Flower complete, and cut vertically. (Baillon.) Fig. 130, III. — Cinnamon. Floral diagram. (Baillon.) 136 FLAVORING AND BEVERAGE PLANTS Fig. 131. — Ginger (Zingiber officinale. Ginger P^imily, Zingerbcracew). Plant showing roots, rootstork, leafy and flowering stems. Flower. Floral diagram. (Baillon.) — A biennial or perennial herl), about 60 cm. tali, with smooth leaves; flowers dingy yellow, aromatically fragrant; fruit a dry pod. Native home, India. of black pepper is due to the volatile oils they contain, the hot biting taste of these spices depends to a considerable extent upon certain resinous substances which are present in small amount. A somcAvhat similar substance, of even greater power, causes the fiery taste of red pepper. MISCELLANEOUS CONDIMENTS 137 Spices have been of singular importance in the history of the world. Li ancient times the spices of the East were among the most valued articles of commerce ' that were brought to the peoples about the Mediterranean. During the Middle Ages cloves, cinnamon, ginger, nutmeg, mace, and black pepper were considered to be as fitting presents for kings as gold and precious stones. Spices together with silk and jewels formed the principal merchandise of the cara- vans which at that time served as the chief means of com- munication between the nations of Asia and Europe. The great desire of European navigators to reach the Spice Islands of the East was the motive which led to many of the daring voyages of the 15th century, and impelled Columbus to brave the Western route that brought him unwittingly to the New World. 53. Savory herbs are such as have aromatic herbage which is used, either fresh or dried, to season or to garnish food. The most familiar examples are sage (Fig. 132, 133), thyme (Fig. 134), spearmint (Fig. 135), .summer savory (Fig. 136), sweet marjoram (Fig. 137), and parsley (Fig. 138). The flavor of each of these herbs depends upon the peculiar volatile oil which it contains, although only a very small amount of the oil is present. Thus there is but 0.2% in spearmint, 0.07% in thyme, and only 0.02% in sage. From this fact one can judge what powerful substances these volatile oils must be. 54. Savory seeds include cardamoms (Fig. 139), and the so-called "seeds" of caraway (Fig. 140), anise (Fig. 141), star anise (Fig. 142), coriander (Fig. 143), and celery (Fig. 79). Cardamoms are true seeds, while the others mentioned, although commonly spoken of as seeds, are in reality seed- like fruits. Savory seeds differ from spices in being commonly used whole rather than pulverized. They all agree in possess- ing a strong aromatic flavor which has led to their use in cookery. As with the savory herbs, their flavor depends upon the presence in each of a peculiar volatile oil, anise having 1-3%, cardamoms 4-5%, and caraway 6%. 55. Miscellaneous condiments. Horseradish and capers are food-adjuncts which differ so considerably from the others 138 FLAVORING AND BEVERAGE PLANTS Fig. 132. — Sage (_Salvia officinalis, Mint Family, Labiakr). Plant in flower, g. Flower, 1. (VUmorin.) — A perennial herb with graj-ish, hairy, aromatic leaves; flowers blue; nutlets brown. Native home, Europe. Fig. 133. — Sago. A, flower, enlarged. B, corolla split down the back and spread out to show the attachment and form of the four stamens; one pair is rudimentary, the others have curiously developed anthers, which are remarkably well adapted to secure the transfer of pollen by bees from one flower to another. C, base of pistil, showing tiie four young nutlets. D, the same cut vertically to show the single ovule in each section of the ovary. (Luerssen.) FLAVORING AND BEVERAGE PLANTS 139 Fig. 134. — Thyme (Thytiius vulgaris, Mint Family, Lahiatce). Plant in flower. (Briquet.) — A perennial, low and shrubby with whitish-hairy aromatic stems aud leaves; flowers lilac or purplish; nutlets brownish. Native home, southern Europe. Fig. 135. — Spearmint {Mentha spicata, Mint Family, Lahiatw). Flowering top, reduced. Flower. Corolla, stamens, and pistil. (Britton and Brown.) — A smooth perennial herb; flowers pale purplish; nutlets brown. Native home, Europe. Fig. 136. — Summer Savory (Satureia hortensis, Mint Family, Lahiatce). Flowering top, reduced. Flower. Caly.K. Nutlet, enlarged. (Britton and Brown.) — An annual with downy stems and leaves; flowers purple; nutlets brown; finely roughened. Native home, Europe. 140 FLAVORING AND BEVERAGE PLANTS Fig. 137. — Sweet Marjoram {Origanum Majorana, ]\Iint Family, Lahiaia). Flowering plant, jS. Flowering branch, }. Flower cluster. (Vil- morin.) — A perennial herb becoming annual in • cultivation, leaves downy; flowers whitish or purplish; nutlets brownish. Native home, Eurasia. Fig. 138. — Parsley (Petroselinum horlensc, Par.sley Family, VmJxUifera). Flowering and fruiting top, reduced. Leaf, upper part. Fruit, side view, enlarged. One-half of fruit cut across to show the six volatile oil- tubes in the wall. (Britton and Brown.) — A mostly biennial herb, attaining 1 m. in height, smooth throughout; flowers greenish yellow; fruit brownish, aromatic. Native home, Mediterranean Region. MISCELLANEOUS CONDIMENTS 141 Fig. 139. — -Cardamoms {Eleitaria cardamomum, Ginger Family, Zingibcra- cece). A, leaf. B, flowering branch. C, flower, |. D, same cut ver- tically. E, F, G, various forms of pods, 3. H, seed, with covering, enlarged. J, K, seed, cut across and vertically, showing the seed-food (p and e) and the embryo {em). (Luerssen.) — A perennial herb with leafy shoots 2-3 m. tall; leaves pale green; flowers whitish, purple- striped; pods pale yellowish; .seeds brown. Native home, India to Java. mentioned in this chapter as to require separate treatment. They agree in being used primarily for their sharp taste. Horseradish is the root of a famihar plant (Fig. 144) which owes its pungency to a minute amount of a volatile oil 142 FLAVORING AND BEVERAGE PLANTS Fig. 140. Fig. 141, I. Fig. 140. — Caraway {Carum Carui, Parsley Family, VmbellifercE). Flower- ing and fruiting top, reduced. Leaf, showing broad attachment to the stem. Fruit, side view, enlarged. Same, cut across, showing six volatile oil-tubes in one-half. (Britton and Brown.) — A biennial or perennial heib, aromatic throughout, becoming 30-60 cm. tall; leaves smooth; flowers white; fruit brownish. Native home, Europe. Fig. 141, I. — Anise (PinipincUa Anisum, Parsley Family, Umhclliferw). Fruiting top, and base of plant. Flower. Fruit, side view, and cut across. (Germain dc St. Pierre.) — An annual about 40 cm. tall, smooth; flowers white; fruit downy, light greenish brown. Native home, Egypt and Asia Minor. Fig. 141, II. — Anise Fruit. A, one-half of a fruit still attached to the slender stalk from which it finally separates. B, the two halves of the fruit cut across to show the numerous volatile oil-tubes in the wall. (Drude.) FLAVORING PLANTS 143 Fig. 142. — Star Anise (lUicium anisatum, Magnolia Family, Magnoliacece). D, flower. C. fruit. B, a pod with seed cut vertically, showing its at- tachment to the axis (a), that of the seed to the pod (h), and the place of the minute embryo (m) in the copious seed-food. (Prantl.) — A, shrubby tree 6-8 m. tall; leaves evergreen, leathery, dotted with volatile oil-glands: flowers yellowish; fruit reddish brown. Native home, China and Japan. Fig. 143, I. — Coriander {Coriandrum sativum. Parsley Family, Umbellif- erce). Flowering and fruiting top. (Baillon.) — An annual growing about 1 m. tall, aromatic; flowers white; fruit yellowish lirown. Native home, Southern Europe. Fig. 143, II. — Coriander. Flower, enlarged. Same, cut vertically. (Rail- Ion.) 144 FLAVORING AND BEVERAGE PLANTS Fig. 143, III. — Coriander. Fruit enlarged. Same, cut across. (Baiilon."* Fig. 144. — Horseradish (Xasturtium Armoracia, Mustard Family, Crucij- ene). Plant in flower. (Baillon.) — A perennial about (iO cm. tall; leaves shining; flowers white, resembling those of mustard in form but smaller. MISCELLANEOUS CONDIMENTS 145 Fig. 145, I.^ — Caper-bush (Capparis spino.sa. Caper Fan>ily, Capparidacea) . Flowering branch showing spines, leaves, flower-buds (which form the condiment), flower, and young fruit. (Baillon.) — A straggling .shrub about 1 m. tall; leaves glossy; flowers white with violet stamens; fruit dry. Native home, Mediterranean Region, and India. Fig. 145, II. — ^Capor-bush. Flower, cut vertically. The ovary is born*: ui)on an elongated continuation of the flower-stalk. (Baillon.) 146 FLAVORING AND BEVERAGE PLANTS (0.06%) very similar to that of mustard if not identical with it. This oil is so powerful an irritant that it will raise blisters when applied to the skin. Capers are flower-buds of the caper-bush (Fig. r45), preserved in vinegar. They contain a peculiar acid, and a volatile oil similar to that found in garlic. Under the head of miscellaneous condiments might also be included such sharp tasting vegetables as radish and onion which have already been considered. Fig. 145, III. — Caper-bush. Floral diagram. Pod. Seed, entire. Same, cut vertically. (Baillon.) 56. Essences are flavoring substances extracted from plants in various ways, often dissolved in water or alcohol, and always in liquid form. Peppermint obtained from the wiiole plant (Fig. 146), wintergreen from the leaves and fruit (Fig. 147), vanilla from the pods (Fig. 148 I), lemon from the rind of the fruit (Fig. 106), and rose from the petals (Fig. 148 II, 148 III) are familiar examples. In peppermint, wintergreen, lemon, and rose the flavoring substance is a volatile oil. In vanilla it is a peculiar crystal- line substance called vanillin, which curiously enough occurs ESSENCES 147 also in the sugar-beet root, and is manufactured artificially from oil of cloves and from pine wood. But these artificial products are inferior in flavor to the natural product extracted from the vanilla "bean." ^m "-^'^ ■i.^.'-'? /^* ' FiG. 146, I. — Peppermint {MentJin piperita, Mint Family, Lahiatw). Flowering top. (Baillon.) — A perennial herb, growing 1 m. tall, aro- matic; leaves bearing numerous minute volatile oil glands; flowers pale purplish; nutlets seldom formed. The oil of wintergreen is likewise manufactured artificiall}'', but in this case the artificial product is indistinguishable from the natural one. Unlike most oils this sinks in water, being indeed the heaviest known of volatile oils. It is a 148 FLAVORING AND BEVERAGE PLANTS Fig. 146, II. — Peppermint. Flowers, enlarged about five times, showing the two sizes often present. (Baillon.) Fig. 147. — VVintergreen {GauUheria procumhetis. Heath Family, Ericaceoc). Plant in flower and fruit, reduced. Corolla with attached stamens spread out. Pod, cut across. (Britton and Brown.) — -An undershrub growing about 5-15 cm. tall; leaves evergreen; flowers white; fruit bright red, consisting of the fleshy aromatic calyx enclosing a dry pod. Native home, North America. ESSENCES 149 Fig. 148, I. — Vanilla (Vanilla planifoh'a, Orchid Family, Orchidacew.) Flowering branch, reduced in size, showing leaves and air-roots. ,4, lip of the flower, and along its hack the "column" formed of style and stamens grown together. B, C, column, side view and front view, show- ing anthers (a) and rudimentarj- stamen (s). D, top of column, cut lengthwise through anthers. E, seed, much enlarged. (Berg and Schmidt.) A tall, climbing herb attaching itself to trees by means of air-roots; leaves thick; flowers yellow; fruit a pod ripening in two years, 16- .30 cm. long, 7-10 mm. thick. Native home, Mexico. 150 FLAVORING AND BEVERAGE PLANTS powerfully acting substance possessing poisonous properties when used in more than very small amount. 57. Non-alcoholic beverages include those made from unfermentcd fruit juices, as, for example, lemonade; those made with syrups flavored with various essences, such as soda water mixtures; and those made by steeping the dried leaves of the tea-plant (Fig. 149), or boiling the prepared seeds of coffee (Fig. L50) or cacao (Fig. 115). The plants ^^55=^^ Fig. 148, II. — French Rose (Rosa gallica, Rose Family, Rosaccce). (Bail- Ion.) — Shrub about 1.5 m. tall; leaves hairy beneath; flowers pink to crimson; fruit brick-red. Native home, Middle and Southern Europe, and Western Asia. This species crossed more or less with others is the principal source of "attar of roses." yielding fruit juices or flavoring matters used for beverages, have already been sufficiently described for our present pur- pose. Tea, coffee, and cacao agree in each containing a crystalline constituent which belongs to the class of substances known as alkaloids. That of tea has been called theine, of coffee caffeine, and of cacao theobromine. Theine and caffeine have been found by chemists to be identical, and to differ but slightly from theobromine. Alkaloids differ chemically from oils and carbohydrates in containing nitrogen, and are distinguished from other FLAVORING PLANTS 151 Fig. 14S, III. — kscotch Rose {Rosa spinosi.'i.'iima. Rose Family, Rosacea). A, flowering branch. B, floral diagram. C, flower, cut vertically. D, pistil, with ovary cut open to show the single ovule within. E, fruit entire. F, same, cut vertically, to show the nutlets enclosed by the fleshy urn-like expansion of the flower-stalk which bears the other floral parts around its rim. (Baillon.) — Shrub about 1 m. tall, very prickly; flowers pink, white, or yellowish; fruit black. Native home, Eurasia. Although this species is not used for making attar it is here included as showing the floral structure more clearly than the more highly cultivated French rose. 152 FLAVORING AND BEVERAGE PLANTS Fig. 149, I. — Tea (Thea sitiensis. Tea Family, Theacece). Flowering branch (Baillon.) — A shrub or tree growing 10 m. tall; leaves evergreen; flowers white, fragrant; fruit dry. Native home, China and India. Fig. 149, II.— Tea. A, flower, entire. B, flower, cut vertically, f, floral diagram. D, fruit. E, seed, entire. F, same, cut vertically. (B.-iillon.) NON-ALCOHOLIC BEVERAGES 153 nitrogenous substances by the fact that alkaloids form com- binations Avith various acids in much the same way that ammonia and other alkalis will do. Among alkaloids are '^ Fig. 150. — Coffee {Coffea arabica, Madder Family, Rubiacew). Plant, show- ing general form. Flower entire, and cut vertically. Fruiting branch. (Baillon.) A small tree growing about 6-8 m. tall; leaves evergreen, glossy; flowers creamy white, delicately fragrant; fruit a crimson berry. Native home, Abyssinia, Mozambique and Angola. included some of the most powerful poisons known and some of the most valuable medicines. Caffeine acts as a poison when taken in more than small amounts. Even in minute 154 FLA\'()RING AND BEVERAGE PLANTS quantity it often has upon the nervous system a marked effect, which may be injurious or beneficial according to circumstances. The coffee "bean" contains about 0.5-2% of caffeine, dried tea leaves about 1-3%. Theobromine, of which there is about 1.5% in the cacao seed, is found to be scarcely soluble in the fluids of the bod}", and thus exerts little if any effect. The most active constituent of each of the three beverage plants we are considering is the aromatic substance to which its pecuhar flavor is due. In black tea there is about .5%, and in green tea about 1% of a volatile oil which is mainly developed during the curing or preparation of the leaves for market. The commercial value of a tea depends mainly upon the flavor imparted by its volatile oil. This flavor is carefully tested by experts who are known as "tea-tasters," although curiously enough they smell rather than taste the samples submitted to them. Even so, the effect of the vola- tile oil upon the nervous system is so powerful as to cause giddiness and headache if the "tasting" be continued more than a few hours a daj^; and it is said that the most vigorous cannot pursue the work for many years without suffering serious consequences. The peculiar aroma of coffee is not found in the raw "bean" but is developed during the process of roasting; that of cacao arises during the process of fermen- tation which the seeds undergo before they are ready for market. In coffee the aromatic constituent is hardh" as powerful as in tea, while in cacao it is so mild that vanilla and various spices are added as flavoring to make chocolate. Finally, mention must be made of an astringent constituent belonging to the class of substances known as tajinins. This forms about 10%, of dry tea leaves. It is similar to the sub- stance extracted from bark for tanning leather. Black ink is commonly made by combining tannin with a substance con- taining iron When taken with food in considerable quanti- ties this astringent interferes Avith digestion. Prolonged boil- ing extracts it in large amount from tea leaves; consequently tea so prepared is most injurious. Steeping for a short time, on the contrary, removes but little of the tannin, while it ex- tracts practically all of the exhilarating and aromatic constit- NON-ALCOHOLIC BEVERAGES 155 Fig. 150, I. — Coffee. Fruit, cut across to show the two seeds (the "coffee beans" of commerce). Same, with lower part removed to show posi- tion of the embryo. (Baillon.) 0 0 a Fig. 151. — Yeast (Saccharomyccs cerevisice, Yeast Family, Saccharomyctta- cece). a, a single becr-yeast plant; groatlj' magnified; h, same sending forth a bud-like protrusion; c, same with bud more developed and a second one appearing; d, a colony produced by such budding without separation; e, a yeast plant divided into four within the enveloping wall ; /, a plant dividing into two, each with a wall of its own, and thus able to resist adverse conditions for a long whUe; g, a cluster of four such resistant plants, one of which upon the return of favorable con- ditions is producing a budding colony; h, such a colony farther ad- vanced. (Luerssen, Reese.) — Beer yeast, the form here shown — used not only for beer but for bread — is not found wild; but the closely similar wine yeast occurs regularly upon the surface of grapes and (in its resistant form in the soil of vineyards) so does not have to be added to the grape "must" in making wine. The plant is very pale brown or colorless. Fig. 152. — -Vinegar Ferment (Bacterium aceti, Rod-germ Family, Bacteria- cece). a, ordinary form of plant, grouped into chain-like colonies, ^{^^ h, an irregular form occurring under very adverse conditions. (Migula.) — The plants are colorless, and form about themselves a mass of jelly which constitutes the "mother" of vinegar. lo() FLAVORING AND BEVERAGE PLANTS uents. A small amount of a tannin-like suljstance is found also in coffee, and in cacao. Cacao, although used as a bev- erage, is so nutritious that it should be regarded rather as a food than as a food-adjunct. 58. Alcoholic beverages and stimulants in general. Alco- holic beverages are either fermented or distilled. Fermented beverages include beers or malt liquors, and wines. Beer, as already stated (sections 19 and 29), is made by fer- menting a sweet liquid obtained chiefly from barley malt. In much the same way that the diastase in the sprouting grain changes the starch into sugar, an enzyme contained in the yeast which is added to the sweet malt liquid, changes its sugar into alcohol and the gas known as carbon dioxid. Yeast is a plant consisting of exceedingly minute bodies of the form shown in Fig. 151. These multiply very rapidly under favorable conditions of food supply and temperature. Hence a small amount of yeast added to a vat full of malt liquid soon becomes a considerable quantity. When the fermenta- tion is well under way the liquid is put into air-tight kegs or ])ottles so that the gas produced may be retained. When the beer is poured out this gas rises to the surface and forms bubbles of foam. After the sugar is converted into alcohol and carbon dioxid gas, the alcohol may be turned into acetic acid (the acid of vinegar) by a plant similar to 3'east (see Fig. 152) unless its action is prevented. This is accompHshed mainly by the addition of hops (Fig. 153) which at the same time impart their peculiar flavor to the beer and give it a bitter taste. The preservative action as well as the flavor of the hops is due chiefiy to a volatile oil of which the fruit con- tains about 1%. The stupefjdng effect of beer is also believed to be due in large part to the flavoring materials derived from the hops. Malt liquors contain about 4-10^^ of alcohol. The process of fermentation may be observed readily by adding j^east to water sweetened with molasses and keeping the mixture for some hours in a warm place. Bubbles of carbon dioxid are given off abundantly and a faint smell of alcohol may be detected. If some of the fermenting mixture be boiled in a flask to kill the 3'east, the neck of the flask being plugged with a wad of cotton wool (which will permit th*" ALCOHOLIC BEVERAGES AND STIMULANTS L57 access of only pure air to th(> mixture), the fermentation will be stopped and the liquid will keep indefinitely. The killing or exclusion of yeasts and similar agents of decomposition from foods to be preserved is the secret of the process of "canning" or "tinning" meats, vegetables, and fruits. Fig. 153. — Hops {Hamulus Lupulus, Mulberry Family, Moracew). 1, branch bearing staminate flower-clu.ster. 3, branch bearing pistillate flower- clusters, and leaves. 3, pistillate flower-cluster. 4' two pistillate flowers and their bract. 5, ripe cone-like fruit-cluster. 6, a single fruit. (Wossidlo.) — A twining perennial herb with rough stems, grow- ing 10 m. tall; leaves rough, hairy; flowers, greenish; fruit, .straw- colored. Native home, Europe, Asia, and North America. Wine is made by expressing the juice of grapes or other fruit and allowing yeast (which occurs naturally on the surface of the fruit) to produce alcoholic fermentation of the 158 FLAVORING AND BEVERAGE PLANTS sugar contained in the liquitl. When this process has gone far enough the fermentation is stopped, generally by heating to kill the yeast and any vinegar ferment that may be present, Fig. 154. — Juniper (J uniperus communis. Pine Family, Pinaccce). Stam- inate flowering branch, ,. Pistillate fruiting branch, i; a, stam- inate flower, enlarged; b, stamen, back view; c, same, lower view; d, two pollen grains; e, pistillate shoot;/, three ovules, and their scales, the front one bent down; g, .same cut across; h, fruit, cut across, show- ing the three seeds in the aromatic pulp formed of the three scales grown together; i, seed, entire; A', same, cut lengthwise to show em- bryo and seed-food. (Berg and Schmidt.) — Shrub with spreading branches, or a tree growing about 12 m. tall; leaves spiny-pointed, whitish above; flowers yellowish; fruit dark blue with a bloom. Native home, north temperate regions. and the wine is kept in tightly closed vessels to exclude the air and all ferments. By standing thus, wines develop with age minute amounts of certain flavoring substances, mostly ALCOHOLIC BEVERAGES AND STIMULANTS L59 volatile oils, or ethers upon which depends chiefly the value of the wine, and probably also to a considerable extent the di- verse effects upon the human sj'stem of different wines of similar alcoholic strength. The proportion of alcohol in wines is about 10-25%. Strong wines have alcohol added after fer- mentation. Champagne is a wine containing a large amount of carbon dioxid gas. Distilled alcoholic beverages include spirituous liquors, such as brandy, rum, whisky, and gin; and liqueurs such as ab- sinthe. Spirituous liquors contain about 40-60% of alcohol. Brand}' is made by distilling wine. Rum is distilled from molasses. Whisky and gin are both distilled from a sort of beer made from grain, generally maize, rye, or wheat. Gin differs from whisky in being flavored with the volatile oil of juniper berries (Fig. 154) and other aromatics. These flavoring matters act powerfully upon the system, and make gin an especiall}' dangerous liquor. Liqueurs are sweetened spirituous liquors containing pe- culiar flavoring matters, usually volatile oils. In the case of absinthe the flavor is due chiefl\' to the volatile oil of worm- wood (Fig. 155). This is a very powerful drug, which, in comparatively small amount, produces violent convulsions. Absinthe acts similarly and is justly regarded as the most pernicious of all alcoholic beverages. All food-adjuncts, as we have seen, are taken with food primarily for their stimulating effect on the system. This effect is shown by more copious flow of the digestive juices, and by generally increased activity of the digestive organs. The very savor of food as we say "makes the mouth water." This is not because stimulating substances bring any con- siderable amount of energy into the body, but because they set free energy which the body has derived from nutritive substances and stored ready for use. Yet, since energy must be expended in digestion, a certain degree of stimulation may be helpful or even necessary. On the other hand, since the release of too much energy works harm, overstimulation is sure to prove injurious; and the danger of overstimulating is the greater from the fact that stimulation is pleasurable even when carried beyond the point of safety. This point 160 FLAVORING AND BEVERAGE PLANTS of safety varies wideh" with different individuals, and in the same individual under different conditions of health and sick- ness, and at different ages. Stimulants, therefore, may be helpful or harmful according to the amount used and the bodily condition of the individual. Overstimulation is al- ways followed by harmful reaction resulting in more or less exhaustion or derangement of the system which may lead to grave consequences, especially in the case of young people. Fig. 155. — Wormwood (Arte7msia Absinthiiwi, Sunfiowci raiiiily. Com- positae). Plant in flower. Leaf and flower-clusters. Outer floret, i. Inner floret, i. (Baillon.) — A perennial herb, about 1 m. tall; leaves white-silky; flowers greenish; fruit grayish. Native home, Europe. All food which has an agreeable flavor is more or les.s stimulating. In vegetable foods as we know the flavor nat- urally belonging to the plant or developed by heat is often strongly marked and characteristic, as, for example, in turnip, parsnip, celery-, cucumber, muskmelon, pineapple, peanut, and pop-corn; and this flavor is due commonly to the presence of a volatile oil, the amount of which, however, is so small that ALCOHOLIC BEVERAGES AND STIMULANTS 1(U overstimulation is not to be feared. On the contrary, the flavoring matter by its presence greatly helps the digestion of the nutritive substances in the food. These natural flavors of foods, as we may call them, are generally all that persons in good health require. Artificial flavors, as we may call the various aromatics added to food, may occasionally be used advantageously and with comparative safety to impart to insipid nutrients mild flavors similar to those of natural foods. Strongly stimulating beverages, however, such as tea, coffee, and alcoholic drinks are seldom necessary to health, and are often injurious to adults, while to 3'oung people they are frequently a source of lasting evils. The use of substances which act so powerfully on the nervous system should be regulated by the advice of one's phj'sician. The effect of artificial stimulants on the human body is much like that of a whip on a horse. We know it to be foolish and cruel to whip a colt, and it may ruin his chances of ever becoming a good horse. It is almost as foolish and may be dangerous to whip a willing horse, although a sluggish horse may need a touch of the whip occasionally to keep him up to his work; and emergencies sometimes arise when a horse must be vigorously whipped to obtain his utmost speed at any risk. So to a healthy child artificial stimulants other than the mildest are unquestionably pernicious; to a healthy adult they are unnecessary and generally harmful ; to persons out of health, sometimes beneficial and sometimes injurious; while on rare occasions they are regarded by many physicians as a necessity for saving life. In such times of special need, however, stimulants are useful to a person only in so far as he has not previously by overuse deprived them of their power. It often happens that an intemperate person dies when a person who had always been temperate would be saved by the stimulant upon which the physician is de- pending. CHAPTER V MEDICINAL AND POISONOUS PLANTS 59. Medicines and poisons. It is an old sayino- that medicines are substances which make the sick well and the well sick. This saying expresses in a way the truth that among medicines are included some of the most powerful poisons known. In fact, most medicines are poisonous, and most poisons medicinal. Experience has shown also that when a fatal dose of a certain poison has been taken, life may sometimes be saved by giving, as an antidote, some other poison in quantity sufficient even to cause death if the first poison had not already been taken. From these facts it appears that no line of separation can be drawn between medicines and poisons. By a medicine we mean any substance used for the cure or relief of disease; and by a poison, any substance capable of injuring the body by other than mechanical means so as to cause death or serious harm if taken in undue quantity. Even too much food may be harmful or perhaps fatal, and the same is true of the most harmless medicines, but in these cases the bad effect is so largely the mechanical result of excessive quantity that we do not say poisoning has taken place. Foods are sometimes used as medicines, as, for example, olive-oil and Irish moss. The same is true of food-adjuncts in general, and, as we have alread}^ seen, many of these if taken in more than small amount are poisonous. We may recall also the fact that certain foods, such as tapioca, are obtained from plants which contain deadly poisons. Similarly the tubers of the white potato when young or when green in color, contain a powerful })oison. Thus it is plain, that edible, medicinal, and poisonous plants must not be thought of as entirely separate and distinct classes, but merely as groups made for practical convenience. 1(52 NON-POISONOUS DRUGS 163 The number of plants which have been used medicinally is enormous. ]\Iany of these, however, have been found to be either so dangerous in their action or of so little value that they are now used if at all only by the ignorant. Neverthe- less, the number of those still used in scientific medicine is rather large. Numerous also are the poisonous plants known to botanists. Plainly, in the present chapter only a small pro- portion of these can be considered. The ones chosen are typical examples of those classes of medicinal and poisonous plants about which it is most important for a beginner to know. The medicinal plants are thus divided: (a) those yielding non-poisonous drugs, and (b) those yielding poisonous drugs. Poisonous plants are grouped into (a) those dangerous to eat and (b) those dangerous to handle. 60. Non-poisonous drugs include various substances which may be more or less nutritious, stimulating, or irritating, or may be useful for their soothing influence upon inflamed surfaces, or for some other mild healing virtue. Some of the substances here included under this heading may perhaps under extraordinary conditions act as poisons; what is meant by calling them non-poisonous is that much larger quantities tha,n are generally used would be required to produce any harmful effects under all ordinary circumstances. The chemical compounds upon wdiich their value mainly depends include mucilaginous or gelatinous constituents, as- tringents, fixed oils, and volatile oils. Various other sub- stances of more or less importance occur in certain of the non- poisonous drugs but these need not concern us here, es- pecially as many of them are not yet well understood by chemists. Mucilaginous or gelatinous substances form the most im- portant part of the drugs known as gum arable, tragacanth, marshmallow, flaxseed, quince seed, elm bark, sassafras pith, Iceland moss, Irish moss or carrageen, and licorice root. Gum arable is an exudation from the trunk and branches of the gum arable tree (Fig. 156) and related species. When pure the gum consists essentially of a carbohydrate called arabin, the formula of which is CioHo.jO,,, the same as that of cane-sugar. Prolonged boiling with dilute acid converts 164 MEDICINAL AND POISONOUS PLANTS arabin into a kind of glucose sugar known as arabinose. A similar substance ^nelding arabinose forms about half of gum tragacanth, about one-third of the gum being a carbo- hydrate called tragacanthin (CcHioOj) which differs from arabin in being insoluble, although it absorbs water and swells exceedingly. Tragacanth is an exudation from wounds made in the stems of the gum-bearing tragacanth shrub f n Fiu. 156. — Gum Arabic Tree {Amcia Souc/al, Pulse P'amily, Lcyuminosw). A, flowering branch. B, flower. C, pod, half, showing seeds. D, seed, cut between the seed-leaves to show seed-stem and seed-bud. E, seed, cut across. (Taubert.) — A tree about 6 m. tall; bark gray; leaves grayish; flowers yellow; pod yellowish. Native home, tropical Africa. This tree yields the best gum ; several other species produce an inferior quality. (Fig. 157) and related species. The root of the marshmallow (Fig. 158) contains about one-third of its weight of a mucilage, having the same formula as tragacanthin. The same formula is given also to the mucilage yielded copiously by the outer coat of the flaxseed (Fig. 279). A similar mucilage but with the formula CisH.2sOi4 is obtained in large quantities from the outer coat of quince seed (Fig. 93). The slipperiness of NON-POISONOUS DRUGS 165 the inner l)ark of our slippery elm and the closely similar English elm (Fig. 159) is due to the large amount of a muci- laginous carbohydrate which it contains. The pith of sassa- fras (Fig. 160) yields to hot water a similar mucilage. Fig. 157. — Tragacanth Shruh (A.--ertically. (Berg and Schmidt.) — Tree growing 20- 30 m. tall; young branches green; leaves becoming smooth, aromatic; flowers yellow; fruit blue on red stalks. Native home. Eastern North America. moist pills to prevent their sticking together. The large amount of fixed oil contained in the spores renders them, moreover, very inflammable, and has led to their use in the manufacture of fireworks, and also as a means of producing artificial lightning in private theatricals. NON-POISONOUS DRUGS 169 Fig. 161. — Iceland Moss (Cetraria islandica, Shield-lichen Family, Par- mcliaceo'). Plant, natural size, growing nearly erect from dry earth. (Luerssen.) — Upper surface brownish or olive, pale below, often red- stained at the base; "fruit" forming chestnut-colored patches on the uppermost lobes. Native home. North America and Eurasia. Fig. 162. — Licorice (Glyc- yrrhiza glabra, Pulse F a m i 1 y, LeguminoscE) . Branch in leaf, flower, and fruit. (Baillon.) — Perennial herb growing about 1 m. or more in height ; leaves pale green ; flowers violet or purple resembling those of a pea; fruit smooth. Na- tive e home, Mediter- ranean Region. 170 MEDICINAL AND POISONOUS PLANTS Volatile oils form the most important constituent of a number of non-poisonous drugs which we have already stud- ied in the last chapter as food-adjuncts; nameh', lemon, caraway, anise, cardamoms, spearmint, sage, ginger, and Fig. 163. — -Medicinal Rhubarb {Rheum officinale. Buckwheat Family, Polygonacew) . Plant in flower. A, flower, entire, enlarged. B, same, cut vertically. C, pi.stil; d. nectar glands. (Baillon.) — Perennial herb growing 2 m. tall; leaves hairy; flowers greenish; fruit, dry, red- dish. Native home. Central Asia. hops. The drugs calamus, asafetida, and saffron are the only others of this class which call for mention here. Calamus consists of the underground stem of the sw^eet-flag (Fig. 167). It contains about 1% of a volatile oil to which it owes NON-POISONOUS DRUGS 171 Fig. 164, I. — Witch-hazel. (Hamamelis virginica, Witch-hazel Family, Hamamelidacece) . Flowering branch. (Baillon.) — Shrub or tree grow- ing about 8 m. tall; leaves downy on veins beneath; flowers yellow, appearing late in the fall; fruit pale brownish; seeds black, shot forcibly from the pods when ripe. Native home. Eastern North America. Fig. 164, II. — Witch-hazel. A. flowers and fruit. B, flower cut vertically and with petals removed. C, fruit, unripe, cut vertically to show the seeds. D, ripe fruit. (Baillon.) 172 MEDICINAL AND POISONOUS PLANTS its pleasant aromatic qualities. Asafetida is a gummy sub- stance obtained by drying the milky juice which exudes from the cut roots of the asafetida plant (Fig. 168 I) and related Fig. 165, I. — Castor-oil Plant (Ricinus communis, Spurge Family, Euphor- hiacece). Plant in flower and fruit. (Baillon.) — A tree-like herl), growing over 12 m. tall in the tropics; leaves and stem often reddish; flowers greenish; fruit smooth or prickly, splitting apart violently and so hurling the seeds to a considerable distance. Native home, probably tropical Africa or India. species. Many people regard it when in full strength as about the most ill-smelling of drugs. It is a curious fact, NON-POISONOUS DRUGS 173 however, that in spite of its odor asafetida is highly valued as a condiment and extensively used for that purpose in Persia and other oriental countries. Nor is its use as a food- adjunct confined to eastern peoples. Many of us have often rehshed it in gravies and sauces, little suspecting that the Fig. 16.5,11. — Castor-oil Plant. .1, staminate flower, just opening. B, same, fully open. C, branching .stamens. D, pistillate flower, entire. E, same, cut verticallj-. F, fruit. G, seed, entire, and cut vertically. H, Embryo. (Baillon.) flavor we were enjoying was due to a substance which is ordinarily most repulsive. The volatile oil upon which the odor and flavor of asafetida depend is chemically very sim- ilar to the oil of mustard, which as we know is pleasant to eat only in minute quantity. Indeed it is almost always true of food-adjuncts that "a little more than a little is by 174 .MEDICINAL AND POISONOUS PLANTS Fig. 166. — Club-moss {Lyropodium clavatum, Club-moss Family, Lycopodiaceoc). 1, plant in "fruit." 2, spore-case, with the scale-like leaf which bears it. 5, spores, highly magnified. (Wossidlo.) — A creep- ing evergreen with somewhat moss-like leaves, and .stem attaining a length of 1 m. or more; spore-bearing cones yel- lowish; spores sulphur-yellow. Native home. Northern America and Eurasia. Fig. 167. — -Sweet-flag (Acorns Calamus, Arum Family, Aracece). A, plant in flower, much reduced. B, flower-cluster, natural size. C, flower, with perianth spread, t. D, floral diagram. E, ovary, cut vertically, V, F, ovule, much enlarged. (Luerssen.) — Perennial herb about (iO cm. tall; flowers greenish; fruit fleshy, reddish. Native to North America and Europe. NON-POISONOUS DRUGS 175 much too much." The opposite effect upon us of the same substance according as it acts in larger or smaller amount is well illustrated also in very many perfumes, and, as we shall Fig. 168, I. — Asafetida Plant {Ferula assa-faetida , Pansley Family, Urn- helliferw). Plant in flower, and part of leaf. (Baillon.) — Perennial herb growing about 2-3 m. tall, with a milky juice of fetid odor; leaves bluish green; flowers pale yellow; fruit reddish brown. Native home, Southwestern Asia. more fully show, in a large proportion of medicines. Saffron consists of the dried stigmas of the saffron crocus (Fig. 168 II). It contains about 1% of a volatile oil of agreeable flavor, and a small amount of a deep yellow coloring matter which 170 MEDICINAL AND POISONOUS PLANTS however is of remarkal)le strength. One part of saffron shaken up with 100,000 parts of water gives a distinct yellow tinge. The principal use of the drug is to impart an attractive color and flavor to mfnUcinal preparations. Most of the Fig. 168, II. — Siiffron Crocus {Crocus saticus, Iris Family, Iridacecp). Plant in flower. Same, cut vertically, Style and stigma.s. (Baillon.) — Perennial herb about 15-25 cm. tall; leaves hairy on the edge; flowers lilac or white, with style-branches bright red, appearing in autumn; fruit dry. Native home, Asia Minor. volatile oils above mentioned are used in medicine mainly for their stimulating effect or for imparting a pleasant flavor to other drugs. 61. Poisonous drugs comprise substances which depend POISONOUS DRUGS 177 for their power upon certain volatile oils, camphors, resiiis, alkaloids, and some other classes of compomids which we shall not need to discuss. A considerable number of the medicinal plants containing poisonous volatile oils we have already considered under the head of food-adjuncts. Cinnamon, wintergreen, clove, peppermint, spearmint, thyme, nutmeg, horseradish, mus- tard, allspice, and black pepper, will be recalled as examples of more or less powerful poisons which nevertheless in very small amount are grateful and often beneficial additions to our food. They are used in medicine partly for their attrac- tive flavor, partly for their stimulating or irritating effect, and partly as antiseptics. ^ Camphors are volatile substances, which form crystals at ordinary temperatures. They bear much the same relation to volatile oils that fats do to fixed oils, that is to say they are volatile oils of comparatively high melting-point. By camphor is most connnonly understood the gum-like drug obtained by distillation from the wood of the camphor-tree (Fig. 169). This drug is conveniently distinguished as laurel camphor or laurinol. Its chemical formula is CjoHieO. The volatile nature of laurinol is prettily exhibited by gently heating a little piece in the bottom of a glass tube held ob- liquely so that the vapor as it rises will come in contact with the cool glass at the upper end. Here will be formed snow- like crystals as the vapor condenses. Similar crystals may be noticed at the upper part of bottles in which camphor has been kept for some time. If small bits of laurel camphor be placed upon the surface of pure water contained in a per- fectl}^ clean vessel the fragments will float and display curious animal-like movements due to the liberation of camphor vapor. The movement is checked by the presence of even a slight trace of oil. Laurel camphor has many important uses which need not here be mentioned. It should be remem- bered, however, that taken internally it is a powerful poison, ten grains (about 0.65 grams) having proved fatal to a child. 1 An antiseptic is a substance which is poisonous to the microscopic germs, or septic organisms as they are called, which cause fermentation, putrefaction, and certain diseases. 178 MEDICINAL. AND POISONOUS PLANTS Peppermint camphor, also known as menthol, CmHooO, is a substance of closely similar properties which is obtained from the volatile oil of peppermint and related species of plants. Its important uses are too familiar to need mention- ing. Although not so powerful a poison as laurinol, yet serious results mav follow its careless internal use. Fig. 169. — Ltmrcl-caniphor Tree {Cinnamomum Camphora, Laurel Family, Lanraccw). Flowering branch, J. (Baillon.) — Tree growing 12 m. tall; leaves thick; flowens yellow; berry dark red. Native home, China and Japan. Resins are non-crystalline solids or semisolids, soluble gen- erally in alcohol, ether, and volatile oils, but insoluble in water. They contain the same elements as volatile oils, but with a larger proportion of ox\'gen. On this account and POISONOUS DRUGS 179 Fig. 170. — Male-fern (Aspidium Filix-mas, Polypody Family, Polypodiacece) . 1, plant showing the rootstock which grows underground and pro- duces roots below, and above gives rise to leaves which unfold from coils (a, a) and finally produce "fruit dots" or sori on the back, i. 2, rootstock cut across showing the woody vessels (a, a) through which the sap runs. 3, segment of the leaf, under side, showing sori or clusters of spore-cases (6) each cluster protected by a cover or indusiujn{a) . 4, a sorus cut vertically across the indusium. 5, the same cut at right angle to -i through the leaf (a), much enlarged to show the indusium (5), and the spore-cases (c). 6', a spore-case discharging spores. (Wos- sidlo.) — A perennial herb; leaves about 30-100 cm. long; fruit dots brownish. Native home, Northern Europe and North America. 180 MEDICINAL AND POISONOUS PLANTS from the circumstance that they are commonly associated in plants with volatile oils it is supposed that they are derived from the latter by oxidation; but they are often complex mixtures of obscure chemical composition. Comparatively few resins are poisonous, and of these, only those contained in the drugs called male-fern and Indian hemp need here Fig. 171, I. — Indian Hemp (Cannabis saliva, Mulberry Family, Moracea). Staminate and pistillate plants. (Baillon.) — ^An annual 1-3 m. tall; leaves roughish; flowers greenish; fruit dry. Native home, Central Asia. concern us. It is the dried and pulverized underground stem of the male-fern (Fig. 170) and related species which con- stitutes the drug long known as a most valuable means of expelling tapeworms. The resin, which is the active con- stituent, has proved, however, in overdoses to be a violent POISONOUS DRUGS 181 poison. The resin of Indian hemp (Fig. 171) is obtained (.'hiefly from the pistillate flower-clusters and fruits. Under the name of " hashish " resinous parts of the plant are smoked as an intoxicant by Eastern peoples. Medicinally the drug is used for its quieting effect upon the nerves in certain dis- eased conditions. It is highly injurious when taken in over- doses, and terrible effects follows its habitual use as an in- toxicant. Fig. 171, II. — Indian Hemp. Staminatc and Staminate flower. Pistillate flower. PLstil. tically. (Baillon.) pistillate flower-clusters. Seed, entire and cut ver- Alkaloids, as we have seen, are vegetable substances which contain nitrogen, as well as carbon, hydrogen, and sometimes oxygen, and like alkalis form salts with acids. While certain of the alkaloids, as for example theobromine, which was referred to in the last chapter, are comparatively harmless in their action upon the human system, others, which are now to be considered, include some of the most powerful of poisons. 182 MEDICINAL AND POISONOUS PLANTS Out of the large number of drugs consisting of or containing poisonous alkaloids the few following may be taken as familiar examples: opium, tobacco, coca, atropine, quinine, strychnine, and aconite. Opium is the dried milky juice which flows from wounds, made in the seed-pods of the opium poppy (Fig. 172). It Fig. 172, I. — Opium Poppy (Papaver somniferum. Poppy Family, Papaver- acea). Flowering and fruiting top. (Baillon.) — An annual about 1 m. tall; leaves pale green; flowers white, red, or purplish; fruit dry, smooth. Native home, iSIediterranean region. has been found to contain twenty different alkaloids. Of these morphine (C17H19NO3) is the most important. The chief uses of opium in medicine are to relax spasm, reheve pain, and induce sleep. Among various oriental peoples large quantities are consumed bj^ smoking and in other ways as an POISONOUS DRUGS 183 Tig. 172, 11. — Opium Popp_\-. .4, flower. B, floral diagram. C, fruit entire showing tlie oblique cuts made for obtaining the opium-milk. D, pod cut vertically to show the numerous seeds on the wall. (Baillon.) 184 MEDICINAL AND POISONOUS PLANTS intoxicant — a practice which leads to most degrading effects upon both mind and body. Tobacco consists of the dried leaves of the tobacco plant (Fig. 173) which have been previously submitted to a process of curing or fermentation. During this process is developed a peculiar volatile substance to which the aroma of the to- bacco is mainly due. The chief active constituent is the Fig. 173. — Tobacco {Nicotiana rustica, and N. Tabacum, Nightshade Family, Solanacece). A, Turkish tobacco (A'^. rustica), flowering top. B, flower, entire. C, same, cut vertically. D, Virginia tobacco {N. Tabacum), flowering top. E, flower. F, pod, opening for discharge of seeds. G, seed. H, same, cut vertically. ./, stigma, (v. Wettstein.) — Turkish tobacco, an annual growing about 1 m. tall; leaves glutinous; flowers yellowish or greenish; fruit dry. Native home, South Americd and Mexico. — Virginia tobacco similar to the Turkish but growing 2 m. tall; flowers rose or purplish. Native home. South America. alkaloid, nicotine (C10H14N2), one of the most virulent of poisons. A single drop of pure nicotine Avill kill a dog. Smaller animals are killed by a whiff of its vapor. A child of eight died from an application to the scalp of juice ex- pressed from fresh tobacco leaves. Medicinally, tobacco is used mainly for its quieting effect in certain nervous affec- tions, but it is now rarely prescribed. No other plant, how- ever, is so widely used as an indulgence. It is estimated that POISONOUS DRUGS 185 over 800,000,000 people habitually smoke or chew tobacco, or take snuff. The effect of tobacco upon the user varies with differences of age, temperament, and manner of living. Thus an amount of indulgence which does not seem to have any ill effect upon the health of a man of middle age and Fig. 174, I. — Coca {Erythroxylon Coca, Coca Family, Erythroxylaceae) . Flowering branch. Leaf. (Baillon.) — Shrub about 2 m. tall; leaves whitish green below; flowers yellow; fruit scarlet. Native home, Peru. Fig. 174, II.— Cotu. Flower-bud. Flower, entire. (Baillon.) Same, cut vertically. phlegmatic temperament who leads an out-of-door life, is found to be plainly harmful to a young man, particularly one of nervous or excitable temperament, and especially if he leads an in».loor life. Whether when taken in moderate 18() MEDICINAL AND POISONOUS PLANTS amount by persons of mature years, tobacco is always in- jurious, is a question with regard to which mecHcal opinion is divided. All competent observers, however, are agreed that unrestrained use invites serious ills, produces enfeebled digestion, heart disease, and nervous debility, and may lead to insanity. Furthermore, all are agreed that even in very small amount, tobacco in whatever form is decidedly in- jurious to young persons, and that habitual use of it may quite unfit them for happy, vigorous life. It is a significant fact that those who are in training for athletic contests are forbidden to use tobacco. The drug coca consists of the dried leaves of the coca shrub (Fig. 174). These leaves mixed with ashes or lime are chewed extensively by the Indians of western South America as a means of lessening the sense of hunger and fatigue. Moderate use by the native mountaineers seems not to injure them, but excessive use produces effects as bad as those following the abuse of opium. Foreigners are found to be especially susceptible to the injurious properties of coca; and although with us it is widely used as a medicine, it must be regarded, like opium, as an especially dangerous drug never to be taken except on advice of one's physician. The effect of coca upon the nervous system appears to be due partly to some volatile substance not yet satisfactorily determined, and to an alka- loid known as cocaine (C17H21NO4). This alkaloid has the remarkable property of producing insensibility to pain within certain restricted regions of the body to which it may be applied. Thus a small amount of a weak solution dropped upon the eyeball permits a surgeon to operate upon that organ without causing the slightest pain. Atropine (C17H01NO3) is another poisonous alkaloid of im- portant use in connection with the eye. An exceedingly minute quantity locally applied causes the pupil of the eye to enlarge, by relaxation of the surrounding muscles, and thus makes possible an examination of internal parts which are ordinarily invisible. The alkaloid is obtained from the leaves and roots of belladonna (Fig. 175) a very poisonous plant. Quinine ((\2H04N0O0) is one of many alkaloids obtained POISONOUS DRUGS 187 Fig. 174, III. — ^Coca. ^4, petal. B, stamens. C, pistil. D, fruit. E, seed, entire. F, same, cut vertically. (Baillon.) Fig. 175. — Belladonna (Airopa Belladonna, Nightshade Family, Solanacecv). A, flowering branch. B, flower. C, same, cut vertically. D, stamen. E, stigma. F, fruit. G, seed. (v. Wettstein:) — Perennial herb grow- ing about 1 m. tall, very poisonous in every part; leaves dull green; flowers dull purple; fruit cherry-like, from green becoming red and dark purple. Native home, Europe and India. 188 MEDICINAL AND POISONOUS PLANTS from the bark of the CaHsaya-tree (Fig. 176) and related species. Its great and -widely recognized value in the treat- ment of malaria is explained by the fact that in quantities not seriously injurious to a human being the alkaloid acts as a deadly poison upon minute parasites which occur in FiCx. 176. — Calisaya-tree (Cinchona Calisaya, Madder Family, Rubiaceoe). A, flowering branch, J. B, flower. C, corolla and stamens. D, fruit. E, fruit with upper half of wall removed to show the packing of the seeds. F, fruit, cut across. G, seed, enlarged, and cut through the embryo, lengthwise. (Luerssen.) — Tree about 12 m. tall; leaves pale green; flowers pink; fruit dry. Native home, Andes of Peru. the blood of malarial patients and are regarded as the cause of the disease. It is highly valued also as a tonic. Its in- tensely bitter taste is a property' familiar to most persons. Strychnine (CoiHocN.jO^), the principal alkaloid obtained from the seeds of the nux vomica tree (Fig. 177), is one of POISONOUS DRUGS 189 the bitterest substances used in medicine. One part of strychnine gives a bitter taste to 700,000 parts of water. It is one of the most violent poisons, but in minute doses is highly valued as a tonic by physicians. The drug aconite is the dried tuber of the monkshood Fit . 177, I. — Nux Vomica {Strychnos Xux-vomica, Logania Family. Lo- ganiaceoe). Flowering branch. (Baillon.) — Tree of moderate height; leaves glossy; flowers greenish or yellow; fruit orange. Native home, India and East Indies. (Fig. 178). This species and nearly related ones are among the most poisonous of plants. The juice of an East Indian species is used by the natives as an arrow-poison which is so powerful as to kill a tiger within a few minutes after it has been even slightly wounded with one of the poisoned arrows. 190 MEDICINAL AND POISONOUS PLANTS The chief active principle is aconitine (C33H45NO12) which is one of several poisonous alkaloids contained in the plant. Medicinally, aconite is used as an external application to re- FiG. 177, II. — Nux Vomica. .1, flower-bud. B, same, cut vertically. C, floral diagram. D, fruit cut across. E, seed, entire. F, same cut through embryo between seed-leaves. (Baillon.) lieve pain; but from what has been said it is plain that great caution should be observed to prevent the introduction of a POISONOUS DRUGS 191 ^KWb^^ ^Hlf^ <3 Fig. 178. — Monkshood {Aconltum Napellus, Crowfoot Family, Ranun- culacece). Plant in flower. Flower. Same, with calyx removed. Flower, cut vertically. Fruit. Flower with sepals detached. Floral diagram. (Baillon.) — Perennial herb about 1 m. tall, very poisonous; leaves dull green; flowers blue; fruit dry. Native home, Europe. 192 MEDICINAL AND POISONOUS PLANTS poisonous quantity into the blood through a scratch or other slight wound in the skin. The plants which produce alkaloids or other poisons would seem to be protected against the ravages of herbivorous animals by means of these substances. All such animals, however, are not affected alike by them. Thus cattle eat poison-ivy without harm, and various insects are known to feed exclusively upon plants which are deadly poisons to higher animals. Commonly poisons are associated with rank odors or disagreeable tastes, but in some poisonous plants which are avoided by cattle and sheep there are no such warnings that we can discover. In the plant's economy the substances in question are to be considered simply as by- products which are sometimes protective. It is a curious fact that many plants may be poisoned by their own alkaloids. For example, an opium poppy is killed if watered with a solution of morphine. 62. Plants poisonous to eat. The number of poisonous plants which are to be found growing wild or in gardens is much larger than is generally supposed, and the cases of poisoning annually reported are more numerous than is commonly realized. While it will not be possible for us to deal with all the species that are dangerous, it \^all be sufficient for our purpose to select for special consideration those which have proved most likely to cause injury. A knowledge of these kinds, and of the waj^s in which poisoning by them has occurred, is not only highly important in itself as a means of safety, but will lead to certain rules of general api)lication. It will be convenient for us to group the different kinds ac- cording to the parts which are most dangerous. Neverthe- less it must be understood that when any part of a plant is poisonous every other part is to be regarded with suspicion. One of the most common ways in which poisoning occurs is from the eating of underground parts of plants which re- semble more or less closely species that are known to bo edible. Thus it has often happened that young folks off for a ramble in the country come across some wild plant that suggests parsnip or some similar herb and has an attractive looking root which has perhaps been uncovered by recent PLANTS POISONOUS TO EAT 193 rains. Being hungry the trampers bite off a piece of the root, and finding that it tastes good they continue to eat it. Before long distressing sj'niptoms appear, leading within a few hours to violent convulsions and perhaps death. The plant of which they have eaten is probably the water hem- FiG. 179. — Water Hemlock {Cicutu maculala, Pansley Family, Umbellifcrw). Lower stem and roots, cut vertically, i. Flowering and fruiting top, h. Part of leaf, 5. Fruit entire, r. Half of same, cut across. (Chesnut.) — Perennial herb 1-2 m. or more in height; roots spindle- shaped, .3-7 cm. long; stem rigid, hollow, smooth; leaves smooth, somewhat celery-like; flowers white; fruit becoming brown. Very poisonous throughout. Native home. North America, in damp soil. lock (Fig. 179) one of our commonest swamp or brookside plants and one of the most deadly. Fatal cases like that described occur almost every year especiall}^ among chil- dren, and manj' cattle are poisoned by eating various parts of the plant. Sometimes poisoning results from drinking 194 MEDICINAL AND POISONOUS PLANTS water in which the roots have been bruised by tramphng. The plant should be uprooted and destroyed wherever found. Another herb closely similar to the water hemlock and too common along waysides is the poison hemlock (Fig. 180). This is most probably the plant by which Socrates was poi- iwSzl'^ Fig. 180, I. — Poison Hemlock (Conium mandatum, Parsley Family, Vm- helliferce) . Flowering and fruiting top. (Baillon.) — A bieimial about 1-2 m. tall; stem, smooth, purple-spotted; leaves parsley-like, of mouse-like odor when bruised; flowers white; fruit brownish. Native home, Eurasia. soned at the hands of the Athenians. Recent cases of poison- ing have resulted from eating the root by mistake for jiarsnip, the leaves for parsley, and the seeds for anise. Children have been poisoned by blowing whistles made from the hollow stem. PLANTS POISONOUS TO EAT 195 Fig. 180, II. — Poison Hemlock. A, flower, cut vertically. B, fruit, entire. C, same, cut across. (Baillon.) Fig. 181, I. — Pokevveed {Phytolacca decandrn, Pokeweed Family, Phyto- kiccacece). Flowering branch. (Baillon.) — Perennial herb 1-4 m. tall; leaves smooth; flowers greenish white; fruit fleshy, dark purple. Native home, United States. Root and seeds poisonous. 196 MEDICINAL AND POISONOUS PLANTS The common pokeweed (Fig. 181) the young shoots of which are often cooked and eaten like asparagus, is very dangerous as regards its root and fruit, and even the herbage may prove poisonous unless thoroughly boiled and the water changed. Death has resulted from eating the root by mis- take for horseradish, parsnip, and artichoke. Children have died from eating the fruit, the seeds of which are especially Fig. 181, II. — Pokeweed. .4, flower. B, same, cut vertically. C, floral diagram. D, fruit. E, seed, entire. F, same, cut vertically. G, root. (Baillon.) poisonous. Household remedies prepared from the plant are widely used, but the cases of poisoning from overdoses of it ignorantly taken show it to be an especially dangerous medicine. The monkshood (Fig. 178) common in gardens is another plant the roots of which have been mistaken for horseradish, with fatal results. The hark of various trees and their roots is often chewed by young people, and often serious and sometimes fatal con- sequences have resulted from mistaking poisonous for harm- less kinds. The locust (Fig. 182) and elder (Fig. 183) have proved especially dangerous in this respect. PLANTS POISONOUS TO EAT 197 Fig. 182. — Locust (Robinia Pseudacacia. Pulse Family, Leguminosce) . Flowering branch. (Baillon.) — Tree growing 24 m. tall, twigs spiny; flowers white and fragrant; fruit a flat brownish pod. Native home, Eastern North America. Fig. 183. — Elder {Samhucus cana- densis. Honeysuckle Family, Caprifoliacew) . Fruiting branch with leaf. Flower. (Britton and Brown.) — Shrub about 1-3 m. tall, leaves nearly smooth; flowers white; fruit deep pur- ple or black. Native home, Eastern North America. 198 MEDICINAL AND POISONOUS PLANTS Fig. 184. — Marsh-marigold {Caltha palustris, Crowfoot Family, Ranuncu- lacece). Plant in flower. (Original.) — Perennial herb, growing 30- 60 cm. tall; leaves smooth; flowers yellow; fruit dry. Native home. North Temperate regions. Fig. 185. — Marsh-marigold. Stamen. Pistil, cut vertically. Ovule. Fruit, splitting open to discharge the seeds. Seed, cut vertically F-ml:)ryo. (Redrawn from Gray.) PLANTS POISONOUS TO EAT 199 The danger attending the use of the herbage of the pokeweed as a pot-herb has already been noticed. Not infrequently deaths are caused by eating the leaves of poisonous wild plants picked by mistake for the marsh-marigold (Figs. 184, Fig. 186. — Indian Poke {I'crutruni viridc, Lily Faniil\-, Liliacecr). Upper and middle section of plant, J. (Chesnut.) — Perennial herl) about 1-2 m. tall; leaves somewhat hairy; flowers yellowish green; fruit dry. Native home, North America. 185), or other spring ''greens." The plant which has proved most dangerous in this way is the Indian poke (Fig. 186). Another common herb which has sometimes been eaten for "greens" with fatal results is the jimson-weed (Fig. 187). 200 MEDICINAL AND POISONOUS PLANTS Fig. 187, I. — Jimson-weed {Datura Stramonium, Nightshade Family, Solanacece) . Flowering and fruiting branch. (Baillon.) — A coarse annual about 1-2 m. tall; stem green; flowers white, heavy-scented, 5-10 cm. long; fruit dry. Native home, Asia (?). Fiu. 187, II. — Jimson- weed. A, flower, cut vertically. B, base of flower cut verti- cally, enlarged. C, fruit opening to dis- charge the seeds. D, seed, entire, and cut vertically. (Baillon.) PLANTS POISONOUS TO EAT 201 Fig. 188, I.— Indian Tobacco {Lobelia influta, Bellflower Family, Cam- Tpanulaccoe) . Flowering top. Tip of flower-cluster. Fruit. (Britton and Brown.) — An annual, growing 1 m. tall or less; leaves hairy; flowers light blue; fruit smooth. Native home. North America. Fig. 188, II. — Indian Tobacco. A, flower, entire, %. B, same, cut verti- cally. C, flower, with calyx and corolla removed. (Luerssen.) 202 MEDICINAL AND POISONOUS PLANTS Young shoots of the elder (Fig. 183) eaten as a pickle have also proved poisonous. The propensity which children have for chewing vari- ous leaves occasionally leads them into danger. A plant which they need to be warned against is the Indian tobacco (Fig. 188) that grows very commonly in pastures and might Fig. 189. — Mountain Laurel {Kalmia latifolia. Heath Family, Ericaaw). a, flowering branch, J. 6, flower, }. c, cki.ster of fruits, i. (Chesnut.) — Shrub 1-12 m. tall; leaves evergreen; flowers pink; fruit dry, brownish. Native home, Eastern United States. Fig. 190. — Sheep Laurel {Kalmia anc/ustifoUa, Heath Family, Ericacccr). Flowering liranch. Flower. Fruiting branch. Fruit. (Britton and Brown.) — Shrub 1.5 cm.-l ni. tall; leaves evergreen; flowers pur- plish or crimson; fruit dry, jjrownish. Native home. Eastern North America. prove alluring perhaps on account of its common name. Every part of the plant is highly poisonous. It has been ex- tensively u.sed in quack medicines and has caused a large number of deaths. Very young i)lants of the mountain laurel (Fig. 189) and the sheep laurel (Fig. 190) are especially dan- PLANTS POISONOUS TO EAT 203 gerous from the rather close resemblance of the leaves of small seedlings to wintergreen or checkerl)erry leaves (see Fig. 147) which children are fond of chewing. The laurels are among our most poisonous plants and have a bad record particularly with reference to domestic animals. Fig. 191. — Snow-on-the-mountain {Euphorbia marginata, Spurge Family, Euphorbiacea) . a, whole plant, J. b, seed pod. (Chesnut.) — Annual growing about 1 m. tall; upper leaves broadly margined with white; flowers greenish yellow; fruit dry. Native home, Western North America. A peculiar danger attaches to the leaves of cherry-trees, especially of the wild black cherry. These trees frequently grow on the borders of pastures where cattle are kept, and it often happens that persons having broken off branches, 204 MEDICINAL AND POISONOUvS PLANTS perhaps to get the fruit, throw the leafy twigs into the pas- tures within reach of the cattle. As the leaves begin to wilt a very powerful poison (prussic acid) is developed by fermen- tation, and manv deaths to stock have occurred from their -^l/;fU-y^-: Fig. 192. — Foxglove {Digitalis purpurea, Figwort Family, Scrophulariacex). A, plant, in flower, reduced. B, flower, ?. C, same, cut vertically. D, E, stamens. F, pistil. G, fruit, (v. Wettstein.) — Biennial or peren- nial 1 m. or less in height; leaves downy; flowers purplish rosy, or white, more or less spotted within; fruit dry. Native home, Europe. Fig. 193. — Lily-of-the-valley (Conrallnria 7)injalis, Lily Family, LiliacecE). Root. Leaves. Flower-clu.sters. Corolla and stamens. Fruit-cluster. (Britton and Brown.) — Perennial herb; leaves smooth; flowers white, fragrant; fruit pulpy, red. Native home. Temperate Eurasia and Eastern United States. PLANTS POISONOUS TO EAT 205 eating cherry leaves in this condition. A similar formation of prussic acid takes place in the kernels of cherry stones in the presence of moisture. It is therefore dangerous to swal- low the fruit whole or to eat many of the kernels. Children have died from so doing. The flowers of poisonous plants are dangerous in two ways : (1) by affording a poisonous honey, and (2) by their at- FiG. 194. — Wood-auemony {Anemone nemerosa, Crowfoot Family, Ranun- culacece). Plant in flower. Flower, cut vertically. (Baillon.) — Peren- nial herb 7-20 cm. tall; leaves nearly smooth; flowers white or pinkish; fruit dry. Native home, Eurasia. The American wood-anemony {Anemone quinquefolia) is so like the species above shown as to be formerly regarded only as a variety of it differing chiefly in having smaller flowers and paler leaves. Fig. 195. — Daphne (Daphne Mezcrcum, Mezereum Family, Thymelaacttp). A, flowering branch. B, flower, entire. C, same, cut vertically. £), fruit, entire. E, same, cut vertically. (Baillon.) — Shrub .30-90 cm. tall; leaves very smooth; flowers rose-purple, fragrant; fruit fleshy, red. Native home, Europe. 200 iMEDICINAL AND POISONOUS PLANTS FiQ. 196. — Oleander (Xerium Oleander, Dogljane Family, Apocynaceae). Flowering branch. (Baillon.) — Shrub 2-5 m. tall; leaves leathery; flowers deep rose-color or white; fruit dry. Native home, Mediterra- nean region. Fig. 197, I. — -Oleander. Flower, cut vertically. (Baillon.) PLANTS POISONOUS TO L]AT 2()< Fig. 197, II. — Oleander. Pi.stil. Stamen, outer view. Same, inner view. Pod, opening to shed the seeds. (Baillon.) !4... r^-'' n\^ Xv_v,* I Fig. 197, III. — Oleander. Seed, entire, enlarged. Same, cut vertically. Floral diagram. (Baillon.) tractiveness leading children to chew them or to suck the sweet nectar they contain. Poisonous honey is yielded by the plant known as snow-on-the-mountain (Fig. 191) which is becoming unfortunately common in gardens, and in some regions is a troublesome weed. Where the plant is abundant 208 MEDICINAL AND POISONOUS PLANTS much of the honey crop is rendered unfit for use. The laurels just referred to are also believed to yield poisonous honey. Among the poisonous plants already mentioned, those having flowers which must be regarded as' dangerously attractive to children are: poppies, tobacco, belladonna. Fig. 198. — Black Nightshade (Solanum nigrum. Nightshade Family, Solanaceoe). Flowering and fruiting branch, '. (Chcsnut.) — Annual 30-60 cm. tall; leaves smooth; flowers white; fruit a black berry. Native home, Eurasia and America. monkshood, pokeweed, jimson-weed, locust, and elder. To these examples may be added the following which have shown themselves similarly dangerous: foxglove (Fig 192), lilj'-of-the-valley (Fig. 193), marsh-marigold (Fig. 184), PLANTS POISONOUS TO EAT 209 wood-anemony (Fig. 194), daphne (Fig. 195), and oleander (Figs. 196, 197). More dangerous than any other parts of poisonous plants are the fruits and seeds, for the reason that they are often of tempting appearance and because fruits in general are good Fig. 199. — Bittersweet {Solanum Dulcamara, Nightshade Family, Solana- cece). a, flowering branch; b, fruiting branch. (C'hesnut.) — A some- what woody vine 1-3 m. long; leaves smoothish; flowers violet-purple with greenish spots; fruit red. Native home, Europe. to eat. In the case of the poison hemlock, the pokeweed, and the wild cherry we have already noticed the poisonous character of these parts. It is safe to regard' all the other poisonous plants mentioned as further examples more or less dangerous in proportion to their attractiveness. That special 210 MEDICINAL AND POISONOUS PLANTS attractiveness, however, is not always a necessary element of clanger in this matter, ai^pears from the following instance which comes from New York. "Four children were playing in one of the public parks of the city where jimson-weeds were growing luxuriantly. The Ijoys imagined themselves Indians and roamed about and ate parts of various plants. Three of them ate the seeds of the jimson-weed. One died Fig. 200. — Mistletoe (Viscum album, Mistletoe Family, Luranthacece). Bunches of the plant growing upon a leafless tree in winter. (Ker- ner.) — Woody parasite, growing on various trees, principally apple and poplars, and attaining a length of 1 ni. or more; leaves evergreen; flowers greenish; fruit a white berry with viscid pulp. Native home, Europe. in a state of wild delirium; another was saved after heroic treatment; . . . the third who ate but few of the seeds was but little affected." This miserable weed has one of the worst records among poisonous plants. Many lives are lost through permitting this plant to grow in places frequented by children. A few further examples of poisonous fruits and seeds re- quire mention. The green berries of the white potato, al- though scarcely attractive to most people, have been eaten PLANTS POISONOUS TO EAT 211 Fig. 201. — Mistletoe. Stem base showing mode of attachment to a branch of the "host" upon which it grows; h, wood of the mistletoe extending into the wood of the host as a primary "sinker" (i); /, /, cambium suckers growing between wood and bark, and sending through the bark buds, as at g, which become shoots; and pushing into the wood secondary sinkers, as at e. e: h, b, wood of the host cut half across at d, d, d, to show the annual rings of growth; c, bark. (Sachs.) Fig. 202. — Mistletoe. 1, pistillate branch with flowers and fruit. 2, pistil- late flower-cluster. 3, staminate flower. 4' pi-stillate flower, cut vor- ticallj-. ,5, fruit, cut vertically. (Wossidlo.) 212 MEDICINAL AND POISONOUS PLANTS with fatal results. The berries of the nearly related black nightshade (Fig. 198) and the bittersweet (Fig. 199) are somewhat poisonous, and from their bright colors especially liable to attract children. At Christmas, young children sometimes suffer from eating the white berries of the mistle- toe (Figs. 200-202) used in decoration. Similar cases of Fig. 203. — -Christmas Holly (Ilex Aquifolium, Holly Family, Aquifoliaceae) . A, branch bearing leaves and staminate flowers. B, staminate flower. C, pistillate flower. D, pistil, cut vertically. E, fruit. F, same, cut across. G, seed. H, same, cut vertically. (Kronfeld, Reichenbach.) — Tree growing 12 m. tall, leaves evergreen; flowers whitish; fruit scarlet. Native home, Eurasia. poisoning are recorded with regard to the scarlet berries of the Christmas holly (Fig. 203). The tempting red pulp surrounding the poi.sonous seeds of the yew (Fig. 204) while itself harmless has sometimes led children to eat the seeds, with fatal results. Young children are also liable to eat the pretty seeds of the castor-oil plant which is very commonly planted for ornament. These seeds are poisonous although, PLANTS POISONOUS TO EAT 213 as is well known, the pure oil expressed from them is quite harmless under ordinary conditions. Some of the worst cases of poisoning occur every year from Fig. 204. — Yew {Taxus baccata, Yew Family, Taxacece). Branches with leaves and staminate flowers (cf), ovule-bearing flowers (9), and fruit (//•.); a, a single staminate flower; b, stamen with anthers still closed; c, same, with anthers open for discharging pollen; d, an ovule- bearing flower, the tip of the ovule seen projecting beyond the pro- tecting scale-leaves; e, same, cut vertically, showing tip of the stem- brancla at x; /, fruit, half ripe, showing the cup-like envelope (aril) growing up from the base of the young seed; g, ripe fruit; h, same, cut vertically; i, seed, cut vertically. (Eichler, Richard.) — Tree growing 20 m. tall; bark, reddish, flaky; leaves dark green above; fruit (aril) scarlet. eating poisonous mushrooms or ''toadstools." While any intelligent person, under competent guidance can learn to distinguish the edible species of fleshy fungi which grow- abundantly in our fields and woods, it is exceedingly danger- 214 MEDICINAL AND POISONOUS PLANTS ous to suppose that one knows, when one does not know. It is indeed hardly safe for one who has not had good botanical training to depend upon even accurate pictures and descrip- tions of mushrooms ; and it is decidedly unsafe for the average person to rely upon information gained from popular writings upon edible fungi. Not a few cases of poisoning within recent years have been traced to the misstatements in, or the misunderstanding of, attractive books or magazine articles on the subject. Another fertile source of danger is belief m the so-called rules "for telhng a mushroom from a toad- stool," such for example as the oft-repeated saying that a piece of silver placed in contact with mushrooms that are being cooked will turn black if they are poisonous. This and all similar rules are worse than worthless for not only is one led by them to regard as poisonous many edible forms, but some of the deadliest species might be called edible. Nothing less than thorough acquaintance with all the botanical char- acters which distinguish our common species at different ages can be relied upon to enable a person to tell the differ- ence between edible and poisonous mushrooms. There are no short cuts to such knowledge. The only really safe way for a beginner to learn about mushrooms with a view to eating them, is to be instructed by an expert botanist, in the field, or from fresh specimeUvS. Until the student has learned the art of observing accurately he should distrust his own ability to determine specimens as edible with the aid of books alone. Meanwhile, it is desirable that he should learn some- thing about our two most poisonous species since the majority of fatal cases have been due to eating specimens of these or closely similar forms. The most deadly of all fungi is the death-cup (Fig. 205). Its name is derived from the fact that the stalk is enveloped at its base by a cup. Beware of any toadstool having such a cup. As the fungus presents an especially attractive appearance and has a pleasant flavor it has tempted many persons to their death. The symptoms of poisoning do not appear for a number of hours after the fungus has been eaten, and by that time so much of the poison has been absorbed into the system that recovery is hardly possible. Scarcely less poisonous, but more common is the PLANTS POISONOUS TO EAT 215 Fig. 205. Fig. 206. Fig. 205. — -Death-cup (Amanita phalloides, Gill-mushroom Family, Agari- caceoe). Mushroom growing 7-20 cm. tall; cap white, straw-color, greenish, light brown, or yellow, uniformly or more or less spotted; smooth and satiny, convex at first, finally becoming concave; stalk white, and nearly smooth, bearing generally at the more or less swollen base a conspicuous cup-like envelope which may lie partly under ground, and near the cap a drooping ring or "frill"; gills white. (Ches- nut.) — Native home, Europe and North America, mostly in woods. The most poisonous and one of most common of mushrooms, dangerous even to handle. Fig. 206. — Fly-amanita (Amanita 77iuscaria, Gill-mushroom Family, Agaricacea). Mushroom growing about 10-14 cm. tall, highly at- tractive in appearance, smell, and taste; cap strongly convex at first, becoming flat or concave, white, yellow, orange to bright red, com- monly deeper-colored toward the center, sticky when moist, always bearing warts of a mostlj' paler color; stalk bulbous at the base, with- out a conspicuous cup but bearing around it flexible shaving-like projections pointing upward, and near the cap a frill-like ring; gills white. (Chesnut.) — Native home, Eurasia, South Africa, North America; mostly in woods. Scarcelj- less poisonous than the death-cup. 210 MEDICINAL AND POISONOUS PLANTS Fig. 207 Fig. 209. Fig. 207. — Caper Spurge (Euphorbia Lathyris, Spurge Family, Euphor- biaccce). a, upper half of plant, J; b, fruit, '. (Chesnut.) — Annual growing 1 m. or less in height; leaves in four ranks; flowers greenish yt'Uow; fruit somewhat fleshy. Native home, Europe; growing in old gardens and as a weed in Eastern States. Fig. 208. — Tall Buttercui> (Ranunculus acris. Crowfoot Family, Ranu)icu- lacece). Base of plant showing roots and leaves, §. Flowering top, i. Fruit enlarged. (Britton and Brown.) — Perennial herb, growing about 1 m. or less in height; leaves hairj-; flowers bright yellow; fruit dry. Native home, Europe; common as a weed in Northern States and Canada. Fig. 209. — Ditch Crowfoot (Ranunculus sceleratus, Crowfoot Family, Ranunculacew). Base of plant, |. Flowering and fruiting top, g. Flower, enlarged. Fruit, (Milarged. (Britton and Brown.) — Annual herb growing 15-60 cm. tall; leaves smooth; flowers yellow; fruit dry. Native home, Eastern North America and Eurasia. PLANTS POISONOUS TO HANDLE 217 handsome fly-amanita (Fig. 206), so called from its use as a fly-poison. It should be noticed that the base of the stalk in- stead of being plainly in a cup is bulbous and scaly. This fungus, like the death-cup, has a pleasant flavor; and after it has been eaten no sign of poisoning is noticed for several hours. Prompt medical treatment may then save the pa- tient's life. 63. Plants poisonous to handle. The number of plants which poison the skin by contact is fortunately much smaller than the number of those poisonous to eat. Among the latter which have been already mentioned the death-cup, the fly- amanita, and the snow-on-the-mountain are the only ones poisonous to handle. The milky juice of the snow-on-the- mountain applied to the skin often causes intense itching and inflammation accompanied by blisters. The same is true of the juice of the nearly related caper spurge (Fig. 207) and of other spurges common in gardens. The colorless juice of several species of buttercups or crowfoots, espe- cially the tall buttercup (Fig. 208) and the ditch crowfoot (Fig. 209), blister the skin. These and related species are sometimes used by European beggars to produce sores as a means of exciting compassion. In the United States by far the worst and most frequent cases of poisoning by contact come from the poison-ivy (Fig. 210) and the poison-sumac (Fig. 211) of the East, and certain of their relatives which live in other parts of the country. Poison-ivy may be distinguished from other com- mon vines for which it is apt to be mistaken, by the fact that its leaflets are in threes and its fruit white. Poison-sumac may be distinguished from the other common sumacs and other shrubs which it resembles, by the smoothness of its twigs and leaves and the even edge of its leaflets together with the slender cylindrical form of the part which bears them, the drooping of the flower-clusters and the greenish- white color of the hanging fruit. The symptoms of poisoning by either plant are inflammation with itching, swelling, and eruption. The poisonous principle of both species has re- cently been discovered to be a fixed oil, called cardol, which is soluble in alcohol. Hence the treatment recommended 218 MEDICINAL AND POISONOUS PLANTS is to rub thoroughly the affected part every few hours with a concentrated sohition of sugar of lead in alcohol of 50-75% strength. As alkalis convert the oil into a harmless soap, Fig. 210. — Poison-ivy (Rhus Toxicodendron, Sumac Family, Anacardiacece) . a, spray showing air-roots and leaves, i; b, fruit, 4. (Chesnut.) — Climbing or trailing shrub becoming 6-15 m. long, sometimes erect and bushj': loaves .smooth or downy; flowers green; fruit smooth, waxy, grayish. Native home. North America. relief is also found by the application of a strong solution of cooking soda, as soon as possible after the poisoning. A fixed oil similar to cardol has been found to be tlie cause of poisoning by two of our native orchids known as lady- POISONOUS PLANTS IN GENERAL 219 slippers (Figs. 212, 213). The symptoms are like those just described, and the treatment recommended is the same. Fortunately there are many persons who are not affectetl b}' handling poison-ivy, poison-sumac, or either of the orchids mentioned; and there are other persons upon whom the effect is but slight. On the other hand, certain persons, particularly women and children, have skins so sensitive as to be poisoned by handling plants which are commonly re- garded as harmless. Thus one occasionally hears of a person who cannot handle the herlmge of the carrot or parsnip, or who cannot wash parsnip roots without being poisoned. In all such cases, as also in cases of poisoning by the other plants referred to in this section, the treatment recommended is much the same as that given for ivy poisoning. 64. Poisonous plants in general. The preceding sections have shown that serious or even fatal consequences may result from eating, chewing, or sucking various parts of poi- sonous plants, or from overdoses of medicines prepared from them; that the juice of certain plants causes painful effects wherever it touches the skin; and that merely handling other kinds produces similar effects with certain persons. We have seen also that the number of common plants, both wild and cultivated, which are poisonous in one way or an- other is much larger than is generally realized. The practical conclusions to be drawn from these facts are surely very plain, but as they cannot l^e too strongly emphasized it may be useful to embody them in the following summary : — 1. Never put into the mouth any part of any plant with which you are not perfectly well acquainted and know to be harmless beyond the possibility of a doubt. 2. Be especially cautious with regard to plants Avhich are young or show only young spring shoots, or which have not come into blossom or fruit; for the younger a plant is, or the fewer parts it displays, the more easily it may be mis- taken for some other kind. 3. Be suspicious of all plants which resemble those known to be poisonous; for such resemblance is likely to indicate relationship, and plants closely related are apt to possess similar properties. But never suppose a plant to be harm- 220 MEDICINAL AND POISONOUS PLANTS Fig. 211. Fig. 213. Fig. 211. — Poison-sumac (Rhus Ve)-nix, Sumac Family, Anacardiaceoe). Fruiting branch. (Chcsnut.) — Shrub or tree 2-15 m. tall; leaves smooth, shining green above, pale beneath; flowers green; fruit grayish. Native home. Eastern North America, in moist ground. Fig. 212. — Showy Ladies' Slipper {Cypripcdium hirsutum. Orchid Family, Orchidacece) . Leaf. Flower. Fruit, i. (Britton and Brown.) — Perennial herb 30-60 cm. tall; leaves hairy; flowers white and crim- son; fruit dry. Native home, Eastern North America. Poisonous to touch. Fig. 213. — Yellow Ladies' Slipper {Cijpripedium parviflorum. Orchid Family, Orchidaceoc) . Base of plant. Flowering top, J. Stigma and stamens, enlarged. (Britton and Brown.) — Similar to the showj' ladies' slipper but flowers greenish yellow, more or less suffused or streaked with madder-purple. Native home. North America. POISONOUS PLANTS IN GENERAL 221 less simply because it bears a general resemblance to certain well-known harmless species; for some of the most poisonous plants very closely resemble and are nearly related to si)ecies highly valued for food.' 4. Place no confidence whatever in any "rules" for telling poisonous from harmless species. 5. Do not suppose that plants which are harmless to birds, cattle, or other animals, may not l)e poisonous to human beings; for many plants which are poisonous to us are eaten by various animals with impunity. 6. Learn to recognize at sight the species of your locality which are poisonous to handle. If possible get some one who knows the plants to point out specimens to you in the field, and show you the features by which they may be always recognized. Then let him test your knowledge on the matter to see if the characteristics of each species are firmly impressed on your mind. If you find you know well all the dangerous species you will feel safe in handling any others. 7. Never use medicines which you do not know to be en- tirely harmless, unless with the approval of your physician. ^ In later chapters the student will be helped to recognize the more important families of plants, and will learn which of them consist en- tirely or almost entirely of poisonous species, and which families are comparatively harmless. Until he is able to classify the plants about him as to their families and is well informed regarding the extent to which relationship may be depended upon to indicate similarity of properties, safety requires that he should regard many harmless species with suspicion. CHAPTER yi INDUSTRIAL PLANTS 65. Uses of industrial plants. By industrial plants we mean those which yield raw materials or products used in the industrial arts; that is to say, in such industries as spin- ning, weaving, building, paper-making, tanning, dyeing, and painting. Industrial plants cannot be separated entirely from edible and medicinal plants any more than those econo- mic groups can be distinguished sharply one from the other; for, as we shall see, there are industrial plants which also yield food or medicine or both. As with the economic plants already studied, so with these, we shall find it convenient to classify them according to the useful products which they yield. Out of the immense number of industrial plants more or less useful to mankind, we can here consider only a few of the most important which yield fibers, uwods, cork, elastic gimis, resins, coloring matters, tannins, oils, and fuels. 66. Fibers in general. Next to food-plants those produc- ing fibers have proved the most useful of all the vegetable kingdom, and have contributed most to the advancement of civilization. Mankind while yet in the stage of savagery needed some sort of cordage easier to procure than sinews or strips of hide, and more suitable for bowstrings, snares, fish-lines, nets, baskets, and the like. He needed also some form of clothing less cumbersome and cooler than that afforded by the skins of animals. These needs were admirably met by twisting, plaiting, or weaving the flexible strands which he found strengthening roots, stems, and leaves, or by spinning the woolly covering of seeds. We know that sheep's wool and other animal fibers, including the silk of which the silk- FIBERS IN GENERAL 223 worm makes its cocoon, were used very early in certain re- gions as materials for fabrics, but in general it is safe to say that vegetable fibers have been far more extensively used than animal fibers even from prehistoric times. As civilization has advanced, and man's needs have mul- tiplied, the uses of vegetable fibers have also multiplied, and their importance in daily life has increased enormously. To-day as their properties are better understood and their wonderful possibilities more fully realized, these fibers are coming to be used more and more in place of animal fibers and other animal products. It is true that mineral fibers, such as asbestos and spun glass, and metals in the form of wire, are replacing vegetable fibers to a limited extent; but in spite of this the consumption of fibers from plants is steadily- increasing. Thej^ are now used most extensively as materials for fabrics, cordage, plaiting, matting, wickerwork, thatch, brushes, stiffening, filling, paper, and various cellulose products. Fabrics are made of especially flexible fibers spun or twisted into yarns, threads, or cords, which are then variously intertwined by weaving, braiding, knitting, or netting. According to its texture a fabric may serve for wearing apparel, house-furnishing, decoration, awnings, sails, tape, belts, girths, webbing, burlap, gunny bagging, hammocks, nets, or lace. The finer fabrics are among the greatest triumphs of human skill and constitute the most highly developed of fiber products. Cordage includes yarn or thread for sewing or needlework, twine, fish-lines, cords, ropes, and cables. These consist, for the most part, of especially strong fibers, which are twisted into strands and then "laid" or twisted again in such a manner that they will not freely untwist. PIniting consists of flat fibrous strands sufficiently pliable to be folded into plaits or flat braids and used for straw hats, fine basketry, and the like. Matting consists of elastic fibrous strands woven or braided into mats or screens. Wickerwork is made of supple t^^-igs, strips of wood or similar fibrous strands interlaced to form hampers and other stout baskets, or chairs and similar articles of furniture. Thatch consists of strips of fibrous material, overlapped and fastened so as to shed water, as on a roof. Brushes, including brooms and whisks, require fibers of special stiffness and elasticit3^ Stiffening, which is mixed with plaster like cow's hair to give cohesion, calls for fibers wliich are at once strong and able to resist the softening influence of the plaster. Filling, such as the stuffing used in upholstery, calking for the seams of water-craft, casks, etc., and packing for objects to be 224 INDUSTRIAL PLANTS transported, require light fibrous material so soft and elastic that it will fully occupy the sj^aces into which it may be crowded. Paper consists of fibers, especiall}' rich in cellulose, which have been soft- ened and compacted, and finally pressed into sheets or molded into other forms as papier-mache'. Besides the more familiar uses of paper for writing, drawing, printing, book-binding, boxes, and so on, there are many others of considerable importance. Thus we have paper garments, paper napkins and other substitutes for fab- rics used in the household, paper pails and similar articles rejilacing wooden ware, paper canoes and paper car-wheels. 8uch wheels hav- ing steel hubs and tires, are found to wear far better than wheels made wholly of steel. Fine paper is nearly pure cellulose. The larger the percentage of cellulose in a fiber the better the paper it makes. Fibers rich in cellulose are also the source of various cellulose prod- ^icts, obtained by chemical means presently to be described. These products include guncotton which is a high explosive used in the manufacture of smokeless powder; collodion, of much use in surgery as a covering for wounds; celluloid, the well-known substitute for ivory, bone, tortoise-shell, and similar materials; and artificial silk which is coming to be used widely in place of the product of the silk- worm. From what has been said of the great variety of uses to which fibers are put, it follows that the term fiber must have a rather broad definition. Fibers may be either fine or coarse, flexible or stiff, elastic or soft. They differ also in structure and chemical composition, and in the part from w^hich they are derived. They agree, however, in being comparatively slender structures, Avhich although separately weak, form strong yet pliable articles of manufacture when twisted, woven, or otherwise intimately joined together. If w^e define fiber-plants as those which j-ield slender parts of economic use when thus united, it may be said that over a thousand species of them are known to be used more or less in various parts of the world. The great majority of these, however, are used only in restricted regions and are not cultivated. Less than fifty are of much commercial importance. Of these the most useful are the species 3'ielding cotton, flax, jute, hemp, and manila. Fibers may be classified most conveniently for our present purpose into the following groups: (1) surface fibers, more or less hair-like outgrowths; (2) bast fibers, consisting entirely of such tough strands as form the bast or strength-giving SURFACE FIBERS 225 Fig. 214. — Upland Cotton {Gossypium herbaceum, Mallow Family, Malva- ceae). Plant in flower and fruit. (Baillon.) — An annual in cultivation, growing 1-2 m. tall; leaves downy; flowers yellow; fruit dry; seed brown. Native home, probably India. part of the inner bark of stems; (3) woody fibers, composed entirely of wood; (4) mixed fibers, containing both woody and bast-hke fibers; and (5) pseudo-fibers, which consist either of entire plants or of parts lacking both wood and bast. 67. Surface fibers occur upon stems, leaves, fruit, and seeds. The only one of much economic importance is cotton. This forms the woolly covering of the seeds of several species, principally the upland cotton (Figs. 214, 215) and the Sea Island cotton (Fig. 216). The former is the chief fiber plant of the world. To-day it is cultivated throughout the tropics and very generally in subtropical regions. The southern United States produce more than all the rest of the world. Two thousand six hundred years ago it was raised in India 226 INDUSTRIAL PLANTS Fig. 215. — Upland Cotton. A, flower-bud. B, flower. C, unopened pod. D, open pod, displaying the masses of hairy seeds. E, pistil. F, stamen. G, ovary, cut across. H, seed showing mass of hairs (cotton). J, same, cut vertically, showing the much-folded embryo. (Baillon.) whence its culture slowly spread. It was introduced into this country in 1774. Long before the coming of Columbus, how- ever, Sea Island cotton was raised bj' the natives of tropical America. Upland cotton yields much the larger amount of fiber which although strong is only about 1-2 cm. long. The Sea Island cotton has a finer fiber, about 2.5-4 cm. long, and is therefore the more valuable; but the yield of the plant is SURFACE FIBEKS 227 Fig. 216. — Sea Island Cotton (Gofisypiurn harbadense. Mallow Family, Malvaceae). Flowering top, I. (Schumann.) — -Similar to upland cotton but with seed black. Native home, West Indies. comparatively small and the cultivation is mostly confined to islands or regions near the coast. The fibers found on the seeds of each consist of simple, flattened and twisted hairs developed as outgrowths from the "hull" or seed coat. In the wild state these hairs catch the wind like thistle-down and so are of service to the plant as means of spreading abroad its seeds. Cotton raisers, however, select varieties which hold their seeds firmly in the pod till they can be picked out by hand. Through .selection also the best varieties have lost the yellowish or hvSi color of their seed hairs, and have become nearly or quite white. At the same time there has been developed in cultivation the remarkable twist before mentioned. This twist is of the 228 INDUSTRIAL PLANTS highest importance. It favors the interlocking of the fibers in spinning and thus makes possible yarns which combine in a wonderful way extreme fineness, softness, and strength. No other fiber has this peculiar twist. Of all others the wool of sheep, from its curliness, most nearly resembles cotton, which indeed well deserves to be called "vegetable wool." The separation of the fiber from the seed after picking is accomplished by a machine called a gin which either pulls the seed from the fiber by means of rollers, or tears away the fiber by the action of notched wheels revolving rapidly be- tween the bars of a grating too narrowly set for the seeds to pass through. The ginned fiber is ready for spinning after various machines have removed impurities^ and combed the fibers approximately parallel. After spinning, the yarn is bleached, or dyed if necessary, and may be then twisted into thread or other cordage, or may be woven or otherwise made into a fabric. The cleaned fiber rolled into sheets is cotton batting, widely used for filling. In their crude state, cotton fibers are covered with an oily varnish which repels water. When this layer is removed and the fibers thoroughly cleansed there is obtained a white, fleecy mass which is highly absorptive. This is extensively employed in medicine and surgery under the name "absorbent cotton." Like the best paper it is nearl}^ pure cellulose. ]\Iany of the finer sorts of paper are made from cotton rags, waste from spin- ning mills, and fibers too short to spin. Absorbent cotton treated with nitric and sulphuric acids becomes converted into nitrocellulose or guncotton. An in- timate mixture of this with laurel camphor forms celluloid. Collodion is a form of nitrocellulose dissolved in ether and alcohol. Artificial silk is made by forcing collodion through exceedingly fine openings into running water, where the collodion at once hardens into a silky fiber, which after thorough washing becomes well adapted to the same uses as natural silk. The carbon filaments of incandescent elec- tric lamps are charred cotton threads or sometimes car- bonized strips of paper pulp. Cotton is the fiber chiefly used also for candle and lamp wicks. 68. Bast fibers form, generally speaking, the strongest BAST FIBERS 229 Fig. 217, I. — Flax (Linum xisitatissimum. Flax Familj-, Linacew). Plant in flower. Young flower-cluster. Seed, entire and cut vertically. (Bail- Ion.) — Annual, about 60 cm. tall; leaves smooth; flowers light blue; fruit dry. Native home, Southeastern Europe and Asia Minor. and most elastic part of the framework of plants. In con- trast ^\ith the woody part they contain commonly a larger proportion of pure cellulose and are thus comparatively little affected by agencies of decay or the various chemicals which destroy or soften wood. The bast fibers of greatest economic importance are flax, jute, and hemp. Flax is next to cotton, the most useful and valuable of all fibers. It has an even wider range of uses, but as its prep- 280 INDUvSTRIAL PLANTS aration requires more labor, it is more costly and hence more a fiber of luxury. The flax plant (Fig. 217) flourishes throughout the temperate zones, and was cultivated in the Old World even during prehistoric times. To-day the world's supply of flax comes chiefly from northern Europe. The bast of a flax plant forms the main strengthening element of its stem, running near the surface where, plainly, the strain is greatest. These fibers consist of nearly solid cylinders of almost pure cellulose. The essentials of the process by which pure flax is obtained are, first rotting or "retting" the stems and then, after drying them, breaking the weakened parts into fragments, and finally beating and combing these away from the bast. After further combing to separate the longest and best fibers, and then bleaching, they are ready to be manufactured into the finest linen fab- rics as well as such strong materials as canvas and duck, and the foundation of carpets and oil-cloth. The strongest thread and twine, and the finest lace are also made from flax, while from linen rags are made the best papers for writing and artist's use. From this paper, by treatment with sulphuric acid, a "vegetable parchment" is made which full}' takes the place of the parchment formerly manufactured from the skin of sheep. Jute is obtained from two closely related species (Fig. 218). Though cultivated from very early times in India the fiber has assumed commercial importance only within the nine- teenth century. The bast is extracted from the stem in some- what the same way as flax. In luster and fineness it rivals flax, but as it contains less cellulose it is inferior in strength and enduring qualities. Its most important use is for coffee- sacks, cotton-bagging, burlap, webbing, and similar coarse fabrics. It is coming rapidly into use, however, for finer fabrics, imitating linen and silk, and as a substitute or adul- terant of hemp it is used extensively in cordage; l^ut it is ill-suited for this purpose on account of its rapid deteriora- tion. Hemp (Fig. 171) is coarser than flax but longer and stronger. It is thus especially well adapted for twine, rope, and heavy cordage, and likewise for sail-cloth, bagging, and similar MIXED FIBERS 231 coarse fabrics. Tarred ravelings of hemp rope are exten- sively used under the name of oakum for calking the seams of wooden vessels and also the joints of iron pipes, and the like. The plant has been grown and its fiber used for many centuries in the Old World, At present the largest supply comes from Northern Europe, and the best quality from Italy. The method of treatment is much the same as for flax. Fig. 217, II. — Flax. Flower, cut vertically. Pistil and calyx. Stamens and pistil. Floral diagram. Pod open for discharge of seeds. Seed, cut vertically. (Baillon.) 69. Mixed fibers consist of slender strands including both bast and wood so intimately united that it is difficult to separate one from the other. Such compound strands form the framework or skeleton of leaves, of many stems, and of certain fruits. The extraction of mixed fibers is commonly an easy matter from the fact that they are for the most part surrounded only by material so soft as to he readily remov- able. In other cases there is so little material beside the 232 INDUSTRIAL PLANTS fibers that isolation of the latter is unnecessary for many purposes. Manila, pineapple fiber, southern moss, straw, rush, maize-fiber, broom-corn, rattan, bamboo, coir, and vegetable sponge will serve as examples. Manila, sometimes called "manila hemp," is obtained from the fleshy leafstalks of a banana-like plant (Fig. 219) grown almost exclusively in the Philippine Islands. The fiber is extracted by scraping awa}^ the surrounding soft Fig. 218, I. — Jute (Corchorus olitorius (A) and C. capsidaris (£)), Linden Family, Tiliacea;). A, flowering and fruiting top of pot-herb jute. D, flowering top of podded jute. (Schumann.) — Annuals about 2-3 m. tall; leaves light green; flowers whitish yellow; fruit drj', elongated in pot-herb jute, globular in the other species. Native home, India. Fig. 218, II.— Podded Jute. Fruit. (Baillon.) parts with a dull knife. Both a coarse and a fine fiber are thus obtained, the latter coming from near the edge of the stalk. The former is much stronger even than the true hemp, and makes the best of cordage. It is highly valued also for mats, bagging, and sail-cloth, while from old ropes of it is made manila paper. Manila bagging serves for stiffening l)laster of Paris in making the building- material known as "staff" which is extensivelv used for the ornamentation of MIXED FIBERS 233 temporary structures such as those of the Columbian and Pan-American Expositions. The fine fiber is woven by the natives into beautiful fabrics. Fig. 219. — Manila Hemp Plaut {Mu.su UxUll.s, Banana Familj', MusacecB). Plant, flowers, and fruit. (Kew Bulletin.) — A tree-like perennial herb from the undergiound stem of which arise huge leaves whose over- lapping stalks make a trunk 6 m. or more in height, and support not only the immense leaf-blades hut the heavy cluster of flowers and fruit; leaves pale beneath; flowers inconspicuous, covered by reddish bracts; fruit green, filled with numerous seeds. Native home, Philip- pine Islands. The leaves of the pineapple (Fig. Ill) yield a similar fiber of extraordinary strength and fineness. From the finest of 234 INDUSTRIAL PLANTS this is made the celebrated pina or pineapple-cloth of the Philippines — said to be the most delicate and perhaps the most costl}' of vegetable textiles. Fig. 220. — Southern Moss {TillandtHa usneoides, Pineapple Family, Bro- mdiacece). A, plant in flower, growing attached to bark. B, flower, enlarged. C, flower, cut vertically. (Wittmack.) — Perennial herba- ceous air-plant hanging from trees to a length of 1-2 m., without roots, covered with grayish scales through which water is absorbed; flowers yellow; fruit dry; seeds hairy. Native home, Southern United States to Brazil. Fig. 221. — Rush {Juncus effusiis, Rush Family, Jitncacece). Plant in flower, A. Calyx, corolla, and stamens. Fruit. Seed, edge and side views. (Britton and Brown.) — Perennial herb 3-12 dm. tall, smooth throughout; flowers greeni.sh; fruit dry. Native home. North America and Eurasia. The fiber extracted from the stem of the so-called southern moss (Fig. 220) by retting is strikingh^ like horsehair in ap- pearance and stiffness, and is largely substituted for it as MIXED FIBERS 235 a stuffing in upholstery. The whole plant also is used as packing material. The straw of wheat, rye, barley, oats, and rice (B'^igs. 1-12) contains so little material besides the fibers, that the whole may be used for many purposes. This straw forms a valuable materia] for packing, filling of mattresses and the like, thatch, jjlaiting for straw hats, baskets, and mats; and for coarse paper and pasteboard. What is commonly known as straw matting — the best sort used in place of carpet — is most gener- ally made of the stems of the rush shown in Fig. 221. Coarse mats are sometimes made of the husks of maize (Fig. 15) which contain strong mixed fibers similar to those of the straw of the other cereals. These fibers and others like them from the stem and foliage leaves are extracted and put to many uses of which the most important is paper- making. Broom-corn (Fig. 222) yields the tough, springy material from which most of our brooms and whisk brushes are made. This consists of the slender branches of the flower-cluster, ripened and deprived of their fruit. Each branch or stalk is little more than a bundle of mixed fibers. Coarse brush material, as for street sweepers, is afforded by the similarly fibrous stems of the rattan (Fig. 223). When split or peeled they serve especially well also, under the name "reed," for basketry, wickerwork, cane seats, etc. The stems of bamboo (Fig. 224) are used widely for similar purposes, and for an almost endless number of other uses. In eastern countries the bamboos form the main dependence of the people in supplying a large share of their needs. In tropical regions generally the coconut palm (Figs. 34-36) is also depended upon for an immense variety of uses — far too many to be here enumerated. Fibrous material obtained from the leaves has important domestic uses, but the fiber of greatest value is that known as coir, which is obtained from the nut husks by rotting away the softer material. Coir makes cordage of extraordinary lightness and elasticity es- pecially valuable for cables and running rigging. Its most familiar use is for door-mats and other matting subject to very hard wear. 236 INDUSTRIAL PLANTS Fig. 222. — Broom-corn (Andropogon Sorghum, Grass ^aInilJ^ Graminece). A, flowering top of wild form, known as Johnson grass (.4. hnlepcnsis) from which broom-corn and the various other cultivated sorgliums are believed to have been derived. B, flowering top of a cultivated form (var. vulgaris) which differs from the form used for brooms (var. technicus)nia,in\y in having a more compact flower-cluster. Bd^, B9, staminate and pistillate spikelets, enlarged. D, bract. K, fruit. G, lodicules. (Rcichenbach.) — -Annual 2-3 m. tall; stem solid; flowers concealed by bracts; fruit a grain. Native home, Mediterranean Region (?). MIXED FIBERS 237 PiQ 003 I —Rattans {Calamus spp., Palm Family, Palmacew). Plants showing their method of climbing over trees by means of grappling hooks at the end of the leaves. (Selleny.)— Woody vmes sometimes attaining a length of 100 m. or more; leaves dark green above; flowers rosy or greenish; fruit polished. Native home, Tropical Asia and l^ast Indies. 238 INDUSTRIAL PLANTS Fibers somewhat similar to those of the coconut husk form a network through the pulp of the sponge cucumber (Fig. 225). These when removed from the ripe fruit form Fig. 223, H. — Rattans. Flowering and fruiting top {Calamus adspersus). A, seed. B, same, cut vertically. C, flower-cluster sheath (of C. Bangka). (Blume.) the "vegetable sponge" which druggists sell for bathing pur- poses. In Japan it is used also in the manufacture of hats, as stuffing for saddles, etc. PSEUDO-FIBERS 239 Fig. 224. — Bamboo (Bamhusa vulgaris, Grass Family, Graminece) . Plants in loaf, ^-i, cluster of spikelets. B, spikelet with stamens protruding. F, flower. (LeMaout and Decaisne, Knuth.) — A tree attaining 26 m. in height; stems hollow; leaves rough; flowers concealed by bracts; fruit a grain. 70. Pseudo-fibers are commonly more or less spongy- masses of material which are most useful as absorbents, al- though serving also for other purposes. Amadou and peat- moss are good examples. Amadou or spunk is a felt-like layer of exceedingly slender fibrils found within the rind of a shelf fungus (Fig. 226). Its most important use is as an absorbent in dentistry. Sheets of it resemble chamois or ooze leather and have been used for caps, table mats, etc. Peat moss (Fig. 227) is largely used as packing material. It is especially valued by horticulturists on account of the 240 INDUSTRIAL PLANTS readiness with which masses of the plant absorb and retain moisture. 71. Woody fibers as here understood, are either slender twigs with the bark removed, or timber mechanically re- FiG. 225. — Vegetable Sponge (Liiffa wgyptiaca. Gourd Family, Cunirhita- cece). Tip of vine showing leaves, tendrils, and young flowers, J. Staminate flower, with corolla spread open. Pistillate flower, cut vertically. Fruit, h- Same, cut across. (Redrawn from Duthie and Fuller.) — .\nnual vine; leaves rough; flowers yellow; fruit 30-100 cm. long, greenish with ten darker ribs. Native home, tropics of the Old World. WOOD IN GENERAL 241 duced to strips or shreds, or else chemically treated so as to separate the ultimate fibrils for paper pulp. Osiers from various species of willow (Fig. 228) afford woody fibers of the first kind which are extensively used for wickerwork. Thin flat strips of willow, poplar (Fig. 253), and other soft woods form the chip of which chip hats are braided. Similar strips of ash (Fig. 245), hickory (Fig. 30), and other hard woods which split easily and evenly make the splint which is woven into large market baskets, chair bottoms and backs, 2) Fig. 226. — Amadou (Fomcs fomentarius, Pore-mushroona Family, Poly- poracccr). C, fruit-body growing out like a bracket from the side of a tree, 3. D, The same cut vertically, to show the numerous fine tubes extending downward vertically from which the dust-like spores fall. 3. (Hennings.) — Brownish or grayish above, rich brown within. Native home, Eurasia, North America, parasitic on beech, etc. and the like. White pine and spruce, shredded by machinery, yield the familiar packing material known as excelsior. Spruce and poplar are the chief woods used for the wood pulp from which the cheaper grades of paper are made, or as an in- gredient in book papers of higher quality. Thus the paper of this book is made of cotton rags mixed with poplar pulp. 72. Wood in general. In economic importance woods rank next to vegetable fibers. Just as the great use of fibers is for clothing, which is almo.st as necessary to us as food, so the great use of wood is for buildings, which are scarcely 242 INDUSTRIAL PLANTS Fig. 227.— Poat-nioss (Sphag- num cymhifoiium, Peat- moss Family, Sphngnaccw). 14, plant in fruit, 1. 15, spore-case, with lid still in place, i. (Kern or.) — Plants soft, yellowish green or purplish; "fruit" dark brown. Native home, throughout the world in bogs and peat swamps. less needful than clothing. Both materials serve us mainly by their mechanical strength, but with this difference, that whereas a fiber of- fers but little resistance except to stretching, a piece of wood main- tains its form but little changed against severe mechanical strains of whatever sort. Hence the great use of wood for support in struc- tures for shelter, storage, transpor- tation, and repose; and its wide application to innumerable minor uses. The ready separation of vegetable fibers and the facility with which they may be twisted and interlaced is matched by the comparative ease with which wood may be shaped and joined. The great importance of the wood-working trades, carpentry, joinery, turnery, and carving in- dicates something of the extent of our dependence upon the ma- terial in which they work. A further idea of the usefulness of this material may be gained from a brief review of the more impor- tant classes of things which are made wholly or in part of wood, and of the qualities they especially require in the material used. Buildings require different qual- ities in the frame, the exterior and the interior finish. Strength, ease of working, and availability in large dimensions are the main needs for the framing timbers; re- sistance to weather or adaptability WOOD IN GENERAL 243 to paint, for exterior finish; Avhile hardness, as little shrink- age as possible, and an attractive appearance when pohshed are most desirable for interior finish. Furniture has needs similar to interior finish and at the same time demands special strength. Domestic utensils have no such need for beauty of material but generally require considerable strength and hardness. Fig. 228, I. — Willow (Salix sp., Willow Family, Salicacece). Staminate flowering branch. Pistillate flowering branch. (BaUlon.) — Trees with yellowish or greenish flowers, dry fruits, and hairy seeds. Native home, throughout the North Temperate Zone. Boxes, including crates, need to be strong and when used for transportation, as hght as possible. Cooperage, whether "dry," as flour barrels, or "wet," as casks and tanks, or "white," as tubs and pails, calls for wood which is stiff yet elastic and not liable to irregular twdsting or warping even when in contact with fluid on only one side. Vessels, including all sorts of water-craft, present in the hull somewhat .similar requirements to wine casks, the chief difference being that the fluid must be prevented from leak- ing in instead of leaking out. As regards the spars, uniform 244 INDUSTRIAL PLANTS stiffness through considerable length together with lightness are most important. Vehicles, in their running parts, require great toughness together with elasticity in order to meet the very severe and frequent shocks and wrenchings to which they are sub- jected; while on the body lightness and stiffness are especially desirable. Fig. 228, II. — Willow. A, pistillate flower-cluster. B, stainiiiate fiov.-pr, enlarged. C, same, cut vertically. D, pistillate flower, enlarged. E, pistil, cut vertically. F, seed, entire. G, same, cut vertically. (Baillon.) Harness though made mostly of other material may con- sist largely or wholly of wood, as with certain saddles, stirrups,, hames, and yokes; and then, as being subject to much the same strains as parts of vehicles, needs scarcely less stiffness, lightness, and elasticity than they. Road materials, including wooden pavements and railway ties, require blocks or logs of exceptional strength and dura- WOOD IN GENERAL 245 bility to stand satisfactorily the heavy loads and the alter- nate drying and wetting to which they are subjected. Fences require wood as durable under similar exposure but without the same mechanical strain. Poles, as for flags and wires, need similarly to resist decay and also to meet about the same requirements as spars. Trestlework, as for bridges and the like, needs especially stiffness with durability under exposure to weather. Piling, as the foundation for bridges, wharfs, and so forth, needs not only to be stiff but to be durable under water or in contact with moist soil. Mine timbering must be equally strong and at the same time able to resist decay under conditions of dampness much more trying than those of entire submergence. Industrial im-plements, machines, and weapons, mostly require wood of especial toughness to serve for handles, cogs, spindles, gunstocks, and the like. Canes and umbrellas call for fancy woods of attractive appearance and considerable stiffness, small dimensions being no drawl^ack. Surgiccd appliances such as splints, crutches, and artificial limbs are best made of wood that is both stiff and light. Recreational appliances such as tennis-rackets, base-ball or cricket-bats, hockey-sticks, golf-clubs, croquet-mallets and balls, nine-pins, balls and bowling alleys, billiard cues, check- ers, and chessmen, are made mostly of wood that is especially tough or hard. Musical instruments such as violins, guitars, and pianos depend for their quality of tone mainly upon the resonance of the wood used in their construction. Toys are made generally of woods which are most easy to work, and the same consideration largely influences the selection of woods for various minor articles such as spools, button-molds, shoe-pegs, toothpicks, and matches. Other uses of wood apart from its value as constructive material will be referred to later. To the plant which produces it, as to us who use it, wood serves mainly for mechanical support. In large trees the trunk must be a column of great strength in order to hold up 246 INDUSTRIAL PLANTS the immensely heavy crown especially when loaded with snow and ice, and severely strained by wind. So also must the branches be joined with great firmness to the trunk, and be stiff enough to hold the foliage well in place. Even the leaves require a woody framework or skeleton to keep their soft, green parts spread open to the sunshine. The woody parts of leaves are continuous with the new wood of the stem which in turn connects with the new wood of the root. What is absorbed by the root is conducted as crude sap mostly through the new wood of root and stem to the food-making parts of the foliage. When as in many trees the new wood is formed next to the bark in successive layers it is distinguished as sap-wood so long as it retains its power of conducting sap. After a certain number of years, varying greatly in different kinds of trees, the wood is no longer useful in this way, but becomes more useful mechanically because of increased dryness, compactness, and strength. It is then known as heart-wood and is commonly distinguished from the sap-wood by a marked change in color. The color is due to the presence of substances formed as by-products of the plant's activities but of no further use to it, and therefore best accumulated in wood which has ceased to be a channel for sap. The sap- wood is also used by the tree to some extent for the storage of food substances, which have but little color, as for example the sweet sap of the sugar-maple. Such food makes the sap-wood a particularly good feeding ground for wood-boring insects and other parasites which injure or destroy the wood. Its greater liability to the attacks of these destructive agents, together with its inferiority to heart-wood in strength lead commonly to the rejection of sap-wood for constructive purposes; while for ornamental uses as well, heart-wood is furthermore preferred on account of its more attractive coloring. A still further advantage of heart-wood for econom- ic use is the much larger masses of it which may be obtained from large trees. Thus we see that wood, especially heart- wood, is the great massive and resistant- material of plants. In slender parts it is, as we have seen, either rep'accd by fibers or shares with them more or less the service of mechani- cal support. Viewed broadly, it may be said that wood cor- WOOD IN GENERAL 247 responds to the bony skeleton of animals in contrast with their tendons and hairs to which we may liken internal and external vegetable fibers respectively. A definition of wood in the economic sense requires that it be distinguished principally from fiber, because of the especially close similarity between them. Fibers, we have seen, are sometimes woody, while all true woods, as will presently appear, are fibrous. Cellulose is the main con- stituent of each. Woods and Avoody fibers contain in addi- tion to cellulose more or less of a substance (or mixture of substances) known as lignin. This is of uncertain chemical composition though known to consist of the same elements as cellulose. Like that substance it permits water and gases to pass readily through it. It is distinguished from cellulose by turning yellow instead of blue when treated with sul- phuric acid and iodine. It is the fact that wood is used in comparatively large, firm masses which chiefly distinguishes it from fibers; while it is the fibrousness of wood that most readily distinguishes it from cork and other massive materials to be presently studied. Let us then for our present purpose define wood as the comparatively hard mass of fibrous ma- terial which serves mainly for mechanical support in plants and in various artificial structures. From earliest times wood has been the most widely useful material of construction. Our civilization has been developed largely upon its possil)ilities. In prehistoric times wherever it was abundant, wood was used almost exclusively for build- ings, utensils, and implements; though in regions less favor- ably situated various substitutes of course had to be found. Even before skill in metal-working had been acquired men were able to shape wood by means of their rude stone tools into many highly useful forms. Thus, only the rudest means are necessary for making from a single log a "dugout" canoe capable of holding many men: a fire kept alive along the top of a fallen trunk burns or chars the wood so that it may be scraped away till the desired form is reached. With the coming of metal tools and their improvement from time to time, more extensive use could be made not only of wood, but also, and for the same reason, of stone and other hard 248 INDUSTRIAL PLANTS materials. With still further mastery over metals both wood and stone have latel}^ come to be replaced rather extensively in building by iron and steel. Nevertheless, in spite of the increased facilities for obtaining and working its various rivals, wood is now being used more than ever. During the past fift}^ years, in this country, each decade has shown a large and steady increase in the amount of wood used pro- portional to the population. The reason for this must be sought in the remarkable advantages which wood possesses over all other materials for a wide range of uses. The economic superiority of wood is well shown for ex- ample, by comparing it with metals such as iron and steel. (1) The supply of wood under proper forest management is practically inexhaustible and very widespread, while mines are not only exhaustible but strictly local. (2) Wood is cheap, and metals are dear because of the much greater labor required in metal-working. Even as lumber, after long- distance transportation, wood rarely costs more than 50 cents a cubic foot, the price of iron being from -55 to $10; while the much greater ease with which wood may be shaped, reshaped, and combined in structures makes it much less expensive to manufacture. (3) Wood is stronger than is commonly sup- posed. In tensile strength, i. e., resistance to a pull length- wise of the grain, a bar of hickory exceeds a similar bar of iron or steel of the same weight. Similarly the resistance to compression parallel to the grain (i e., against the ends of a stick) is found to be greater in a selected piece of hickory or hard pine than in a rod of wrought iron of the same weight and height. Though under certain conditions iron appears to be much stiffer than wood, it is found that a ten-foot beam of hard pine requires considerably more load to bend it by one inch than a similar bar of iron of same weight and length. (4) Wood endures a far greater distortion than metal with- out losing its power to recover the original form. (5) Wood does not rust or crystallize like metal, and, (6) as wood is a poor conductor of heat it is not only pleasanter to touch but when used as the chief material of dwellings and ships has none of the injurious effects of iron and steel. (7) Wooden beams though combustible, are often safer in case of fire than WOOD IN GENERAL 249 iron ones because the latter twist out of shape at high tem- perature in a way to wreck the entire structure. (8) Being unaffected by wines or other weak acids, and imparting no disagreeable flavor, certain woods may be used for casks where metal would be objectionable or even poisonous. (9) Woods have an organic beauty unrivaled by metals. (10) The peculiar elasticity of certain woods render them incomparabl}' superior to any metal as material for the res- onant parts of violins and similar musical instruments. (11) Pieces of wood may be easily and strongly united simply by glueing, while metals recjuire the more difficult operation of welding or soldering. As against wood it must be said (1) that it cannot be melted and cast or rolled; though by steaming, rods or sheets may be readily bent into curves of small radius; and when reduced to pulp, as we have seen, it can be pressed into almost any shape. (2) It shrinks or expands with variations of moisture, more than metals do under ordinary variations of temperature. (3) It decays unless proper precautions are taken to prevent, though under water wood lasts longer than steel or iron. (4) It is more easily crushed than iron and therefore is not so well suited for bearing the greatest weights or for resisting very heavy blows. (5) Finally, the greater hardness of many metals gives them obvious advantages over wood for sharp imple- ments and a large variety of ol)jects that have to stand severe wear. A great deal is often gained by combining wood and metal because the properties of one so largely complement those of the other. A piece of wood consists essentially of a mass of extremely slender fibers or fibrils, each comparable to a fibril of cotton, but firmly cemented together. The valuable qualities of woods, and their defects as well, depend in great measure upon the character and arrangement of these fibrils and of similar parts associated with them. Therefore some knowl- edge of the structure of wood helps us to understand its prop- erties and to tell one kind of wood from another; and thus should lead us to a more intelligent, economical use of the material. The fibrous nature of wood is clearly shown by its splintery fracture when broken across the grain and by 250 INDUSTRIAL PLANTS its separation into more or less delicate strands when crushed. Those who have had experience in chopping Avood know that the ax cleaves as a rule most easily when cutting toward the center of the log; less easily in an}' other lengthwise direc- tion, and least easil}' when directed slantingly or directly across the grain. This shows that the structural parts have a peculiarly definite arrangement. Something of this appears when we examine, for example, with a strong magnifier, the surface of a piece of pine wood, cut radially, i. e., toward the center of the log. We see, as shoA\ai in Fig. 229, that the wood is made up mainly of very slender, thin-walled tubes Fig. 229. — Radial section of white pine wood, ters. (Original.) Magnified about 50 diame- each closed and tapering at the ends; and besides these are numerous flat bundles of much smaller tubes running at right angles to the others and radially. These bundles of finer structure are called pith-rays because they are some- what similar in texture to a cylinder of 29?7/z in the center of the log, and some of them at least, are extensions of it. Their relative softness makes the wood most easily separated along the planes in which they lie. Even to the naked eye their peculiar sheen makes the pith-rays apparent on a radial surface, and gives an especially attractive prominence to them in Avhat the dealers call " quarter-sawed " timber. It is plain also that the fibrils, by which name we shall understand WOOD IN GENERAL 251 the closed longitudinal tubes that form the main part of wood, cannot be all just alike for they occur in alternating layers of darker and lighter color. Examination of these layers under the magnifier shows that in the lighter colored layer the tubes are of decidedly larger bore than those form- ing the darker layer. The pale layers of less compact ma- terial are called spring wood, and the more compact layers, summer wood, for reasons that will presently appear. On a tangential surface, that is to say, one cut with the grain but not toward the center of the log, these contrasted layers Fig. 2.30. — -Tangential section of white pine wood, \". (Original.) Fig. 231. — Transverse section of white pine wood, Y. (Original.) appear as broader bands often in beautiful systems of curves. On such a surface the cut ends of the pith-rays are to be seen under the magnifier (Fig. 230) as small, very narrow spots or streaks. If now we examine a crosscut or transverse section (i. e., a thin slice made at right angles to the direction of the fibrils) the magnifier will show us something more of the form and arrangement of the parts. As shown in Fig. 231 we can look through the central cavities of the tubular fibrils, and so get a better idea of their sizes and shapes and the thinness of the walls. They are seen to be arranged in radial rows, between which the pith rays often appear as more or less delicate lines of dense material. Here and there among 252 INDUSTRIAL PLANTS the fibrils we see circular holes many times larger than the fibril-cavities. These arc long, tubular reservoirs (tailed resin-ducts from the material they contain which oozes out at a wound. On longitudinal surfaces they appear as more or less conspicuous j'ello-wish or brownish streaks. In many woods there are no resin-ducts present, but there are numerous, commonly empty, canals sometimes con- siderably larger than resin-ducts and sometimes much smaller in diameter. They form a continuous system of tubes throughout the wood. Their appearance, viewed endwise, is shown for various woods in Figs. 235-24 L They are known as pores or vessels, and in the sap-wood serve as pipes or reservoirs for conveying upward the crude sap absorbed by the roots or for storing it, together with more or less air, temporarily till needed. They thus share "with the wood- fil)rils the office of conduction whidi is performed alone by the fibrils of such woods as pine. Figure 232 shows in a somewhat diagrammatic way the rela- tive position of the various structural elements found in pine wood, with reference to one another and to the pith- cylinder within and the bark without. Between the bark and the wood is found a thin layer of soft, living material called the cambium (c) which is of vital importance because from it, after the first year, all the wood and bark is formed. At the beginning of each season's growth the cambium works vigor- ously and forms numerous full-size wood-fibrils, but as more and more new wood is added to the old, an increasing pressure results unless the bark yields readih' to the strain. In many cases the bark holds firmly and this pressure is partly ac- countable for the fact that summer wood is commonly more compact than spring wood, which as we have seen results from the progressive flattening of the fibrils in the radial direction. Through the winter the outer bark becomes suffi- ciently cracked by the action of the weather to relieve the pressure upon the parts wdthin; consequently at the return of spring the cambium can resume its Avork of wood-building under the most favorable conditions. As a result of these alternating changes of conditions, which in our climate are connected with the annual changes of temperature, we have WOOD IN GENERAL 253 in the wood what are known as annual rings or layers. In warm regions where comparatively uniform, conditions pre- vail throughout the year, many trees grow continuously and the wood shows no annual layers at all. Sometimes pe- culiar conditions affecting growth give rise to layers inter- mediate between the annual ones, and these subdivisions of / ffi l9 } 1 Fig. 232. — -Wedge of a four-year-old pine stem cut in winter, showing, somewhat diagrammatically, a transverse surface (2 INDUSTRIAL PLANTS Fig. 250, Magnolia, Bull Bay (Magnolia grandiflora. Magnolia Family. Magnoliacecc). Flowering branch. Floral diagram. Fruit. (Baillon.) — Tree growing 24 ni. tall; loaves evergreen; flowers white, fragrant; fruit rusty lirown; .seeds bright red, dangling on threads. Native home, North Carolina to Texas. TRUE WOODS 263 Cherry as found in the lumber market is almost entirely the wood of the wild black cherry (Fig. 247) although the wood of other species may sometimes be offered. Its fine texture and attractive color make it one of the most desirable of finishing lumbers. Plum (Figs. 95, 239), very similar to cherry, is used similarly but more rarely. Maple, especially sugar-maple (Fig. 248) has all the quali- ties necessary for flooring, paneling, and other interior finishing. It is highly valued also for the keels of vessels. As a material for furniture "curly" grained or "bird's eye" varieties are in great demand. Its fine texture and uniform hardness adapt it also for shoe-lasts and other form blocks, for shoe-pegs, showbill type, parts of pianos and other musical instruments, and for use in carving and turnery. Tulip whitewood (Fig. 249) is used in enormous quantities for a great many purposes where fine texture, ease of working, and stiffness are required but not much strength. Interior finishing, furniture, carriage and wagon bodies, parts of implements and machinery, and many kinds of woodenware, boxes, and toys show the wide range of its usefulness. Magnolia (Fig. 250), has a wood so closely resembling that of the tulip whitewood as to be frequently used for similar purposes. Basswood, obtained from the linden tree (Figs. 251, 252), re- sembles the sap-wood of magnolia in appearance and proper- ties. On account of its lightness, uniform texture, and pale color it is used especially for the bottoms of drawers, for carv- ing and pyrography, and because of its stiffness serves well for trunks. Poplar (Fig. 253) obtained from various species, is a very soft, light wood of limited use in building and furniture making; but found to be suitable for sugar and flour barrels, cracker boxes, crates, and certain articles of woodenware. Birch (Figs. 240, 254) of various species is a wood resem- bling cherry in its properties, and when stained to imitate it, is often used in place of the more expensive material for interior finishing and furniture. It is used commonly also for spools, turned boxes, wooden shoes, shoe-lasts, shoe-pegs, wagon- hubs, ox-yokes, and many other carved or turned articles. 264 INDUSTRIAL PLANTS Fig. 251. — Elni-l(>uvf(i Linden (Tilui ulmifolia. Linden Family, Tiliacea). Flowering branch. Flower, enlarged. Same, cut vertically. (Bail- Ion.) — Tree 30 m. or more tall; bark grayish; leaves whitish beneath; flowers cream-color; fruit brownish. Native home, Europe. Fig. 252. — Linden. Floral diagram. Fruit. Seed, entire. Same, cut vertically. (Baillon.) Fig. 25.3. — Poplar, American Aspen (Populus tremuloides. Willow Family, Salicace(T). Leafy branch, 5. Leaf. Staminate flower-cluster. Pistil- late flower-cluster. Pistillate flower. Seed. (Britten and Brown.) — Tree about 30 m. tall; leaves with stalk flattened at right angles to the blade, flowers greenish; fruit dr,\-. Native home. Northern North America. TRUE WOODS 265 Fig. 254. — White Birch (Betula alba. Birch Family, Betuhiceae). 1, flowering branch. 2, fruiting branch. 3-6, staminate flowers. *6, stamen. 7, part of pistillate flower-cluster. 8, group of pistillate flowers, outer view. .9, same, inner view. 10, bracts. 11, 12, the same as ripened in the cone. 13, fruit. 14, winter twig. 15, a three-year-old twig, cut across. (Willkomm.) — Tree growing 24 m. tall; bark white; leaves and young twigs resinous; flowers yellowish; fruit brown. Native home, Eurasia. 266 INDUSTRIAL PLANTS Mahogany (Fig. 255) is pre-eminently the joiner's wood, being preferred to all others for cabinet making of all sorts, interior finish, and ornamental work in general. Fid. 255. — Mahogany (Swirtenia Mahoguni, Melia Family, Melmcar). A, flowering brancli. B, flower, cut vertically, with cal^TC and corolla removed. C, staminatc tube. D, pistil. E, bud. F, fruit. G, central column of fruit with seed attached. H, seed. J, fruit-valve, side view. (Harms.) — Tree 21 m. tall; leaves smooth, flowers greenish yellow; fruit dry. Native home, Tropical America. Orange-ivood (Fig. 106) although attractive, is available only in such small quantities that its use is mostly restricted TRUE WOODS 2()7 Fig. 25G. — American Sycamore or Buttonwood (Platnnus occidentalis. Plane-tree Family, Platanacece) . 'A, flowering branch; at a staminate flower-clusters, at b pistillate flower-clusters, and at n the tubular stipules. B, pistillate flower, enlarged. C, staminate flower after loss of the anthers. D, floral diagram. E, stamen of Mexican .sycamore. F, ovary, cut vertically. G, fruit, cut vertically. H-K, hairs from leaf, magnified. L, M, fruit hairs, magnified. (Schoenland, Niedenzu.) — Tree growang 40 m. tall; bark, cream-colored with patches of l)rown; leaves hairy; flowers greenish; fruit brownish. Native home. Eastern States. 268 INDUSTRIAL PLANTS to such minor articles as toothpicks, canes, and souvenir or- naments. Sycamore (P^ig. 256) is just coming to be appreciated as an ornamental wood capable of charming effects in cabinet work and interior finishing, especially with quarter-sawed ^>~. Fig. 257. — European Beech (Fagus ni/lvatica, Beech Family, Fagacew). 1, flowering branch, showing staniinate flower-cluster at a, and pistil- late cluster above. :2, staminate flower. 3, pistillate flower, cut ver- tically. 4» ovaries, cut across. 5, fruit with cup and nuts. /!, nut. (Wossidlo.) — Tree growing .35 m. tall; bark smooth and grayish; leaves fringed when young; flowers purplish; fruit brown. Native home, Europe. stock; though for parts less exposed to view, such as the inside of drawers, and for cooperage and boxes it is exten- sively used on account of its stiffness and strength. Beech (Figs. 241, 257) resembles sycamore in its properties, and is used in somewhat the same ways by cabinet makers and turners. TRUE WOODS 269 Olive-wood (Fig. 113) on account of its hardness and attrac- tive coloring is prized for many small articles of turnery and carving and for other ornamental purposes. Apple-wood (Fig. 91) for its similar compactness and uni- form, close grain is likewise highly valued for tool-handles, mallet-heads, knobs, and other articles of turnery. 16 18 13 17 Fig. 258. — .Scotch Pine. {Pinu-'i sylicstris, Pine Fsunily, Pinaceo'). 1, young branch bearing a pistillate flower near the tip. 2, branch bearing staminate flowers. 3, cone, still closed. 4, same open for discharge of the seeds. 5, pistillate flower, B. 6-8, o-vule-bearing scale, front, side and back views. 9, ripe scale with seeds attached. 10, same, back view. 11, seed and wing. 12, lower part of wing. 13, staminate flower. 14, 15, stamens. 16, 17, pollen grains, much magnified. 18, seedling. 19, branchlet bearing two foliage leaves. 20, leaves, cut across, enlarged. (WDIkomm.) — Tree growing 36 m. tall; bark rough, brownish; leaves bluish-green; flowers yellowish; fruit reddish brown. Native home, Eurasia. 270 INDUSTRIAL PLANTS Pine (Figs. 229-232, 258) is used more extensively than any other kind of wood, and finds a place in almost every wood-working industry. The ciualities which give it this pre-eminence are mainly that it works easily, is never too hard to nail (unlike oak or hickory), is for the most part very durable on account of the preservative effect of the resin it contains, and, for the same reason, is not much sub- ject to the attack of insects. The several species which come into the market are sold either as hard or as soft pine but the difference is not always well marked. Soft pine (mainly wdiite i^ine) is the principal wood used in conmion carpentry-, and enormous quantities are consumed also in white cooper- age, cabinet work, to3'-making, pattern-making, and ship- building; and for crates, boxes, etc. Hard pine is most ex- tensively used in heavy construction, especially for bridges and similar exposed work; and is unequaled for spars, masts, planks, ship-timbers, and heavy beams. It has especial advantages for flooring and exposed stairways on account of its durability. Larch (Fig. 259) is very like hard pine in appearance, qualities, and uses. For ship's "knees" {i. e., angular braces giving stiffness to the frame) the lower part of the tree as it curves naturally when growing in swamps has great advan- tages. Owing to its durability the trunk is valued also for telegraph-poles and railway-ties. Spruce (Fig. 260) resembles soft pine in appearance and qualities and is commonly put to the same uses. Being re- markably resonant it is preferred to all other woods for the sounding-boards of pianos, and the bodies of violins, guitars, and similar stringed instruments. Red cedar (Fig. 261) has just the lightness, softness, and even texture required for lead-pencils; and is used in very large quantities for that purpose, almost to the exclusion of other woods. It also finds a place in cabinet work and for cooperage; likewise for fence posts on account of its unusual durability in contact with soil. Redwood (Fig. 262) closely resembles red cedar in appear- ance and qualities and has many of the same uses. Its great durability makes it highly valued for shingles, and its large TRUE WOODS 271 dimensions and rich color give it especial advantages for certain jjurposes in cabinet work and interior finish. Hemlock (Fig. 263) is soft and stiff though brittle, com- monly cross-grained, coarse, and splintery. It is of value chiefly for rough carpentry, and raihvay-ties. Fig. 259. — European Larch (Larix decidua, Pine Family, PinacecF). I, twig with long and short branches, and with a cone continuing as a branch at a. 2, twig with staminate and pistillate flowers. 3, staminate flower, 1. 4-6, stamens. 7, 8, 9, scales from young cone. 10, ripe cone. 11-13, seed-bearing scales. 14, seeds, with and without wing. 15, short branch or "spur," cut vertically. 16, leaf, entire, and cut across. (Willkomm.) — Tree growing 30 m. tall; bark dark grayish- brown; leaves bright green; staminate flowers yellow; pistillate flowers purplish; fruit brownish. Native home, Europe. 272 INDUSTRIAL PLANTS 74. Pseudo-woods, as we have seen, may be defined as more or less wood-like materials which, however, show no trace of pith rays or annual rings. Under the name porcupine-wood the outer harder part of I Fig. 260. — Norway Spruce {Ficra crccL-ia, Pino Family, Pinacew). 1, twig bearing staminate flowers. 2, twig bearing a pistillate flower. 3, ripe cone. 4-6, cone scales, bearing seeds. 7, seeds, with and without wing. 8, stamen, two views. 9, leaf, entire and cut across. 10, seed- ling, with seed-shell still attached. 11, same, older. 12, a "pineapple gall" produced by the spruce aphis (Chcrmcs abictis). (Willkomm ) — Tree growing 4.5 m. tall; hark reddish brown; leaves dark green, glossy; flowers purple; fruit brown. Native home, Europe. Much planted. INDUSTRIAL PLANTS 273 Fig. 261. — Red Codar {Junipenis r.irginiana. Pine Family, Pinacece). Fruiting branch, I. Leafy tip. (Britton and Brown.) — Tree growing 30 m. tall; bark brownish, shreddy; leaves dull green; flowers yellowish; fruit light blue. Native home, North America. Fig. 262. — Redwood (Sequoia senipervirens. Pine Family, PinacecF). Fruit- ing branch. (Nicholson.) — Tree growing over 100 m. tall; bark reddish brown; leaves mostly scale-like; flowers inconspicuous; fruit brownish. Native home, California. Fig 263. — Hemlock (Tsuga canadensis. Pine Family, Pinacece). Leafy branch, h. Staminatc flower. Cone. Cone-scale. (Britton and Brown.) — Tree growing over 30 m. tall; bark flaky; leaves dark green above; flowers yellowish; fruit brownish. Native home, Eastern North America. 274 INDUSTIUAT. PLANTS the coconut trunk (Fig. 34) is imported for the use of cabinet makers in ornamental work and to some extent for canes. Canes of rather curious appearance are made sometimes also from the mid-rib of the gigantic leaves of the date-palm itXG. 264. — Tree-cabbage (Brassica olcracea var. accphaUi, Mustard Family, Cruciferw). Plant, I'j. (Vilmorin.) — Perennial herb growing 2 m. tall; leaves, etc., as in other forms of cabbage. Native home. Western Europe. (Fig. 108). Another curious walking-stick is made from the stalk of an extraordinarily tall variety of cabbage (Fig. 264). The bamboo (Fig. 224) of which there are many species, has, as is well known, a very wide range of uses among which the most familiar to us are for canes and umbrella handles, fishing- INDUSTRIAL PLANTS 275 Fig. 265. — Bottle-gourd (Lagenaria vulgaris. Gourd Family, Cucxirhitacew). Plant in fruit, 12. Flower. (Vilmorin.) — Annual, climbing by tendrils to a length of 10 m. or more; hairy throughout; flowers white; fruit yellowish or orange, very various in form, sometimes 2 m. long. Native home, Old World Tropics. Fig. 266, I. — Vegetable Ivory (PInjtelephas microcarpa, Palm Family, Palmaccw). Plants, in flower, a staminate plant in front, and a pistil- late one behind. (Karsten.) — Shrub with short stem sending up leaves 7-8 m. long; fruit dry. Native home. Tropical America. 276 INDUSTRIAL PLANTS rods, articles of furniture, and various ornaments. In tropical and eastern countries where bamboos flourish, the lises to which the light, strong stems are put would require pages to enumerate. The hard parts of certain fruits may be considered also as pseudo-woods, and are sometimes put to minor uses of importance. The hard inner .shell of the coconut forms the Fig. 266, II. — Vegetable Ivory. .4, pistillate flower-cluster in bud. B, staniinate flower. C, stamen. D, pollen. E, pistillate flower, cut vertically, showing pistil accompanied by n.idimentary stamens. F, fruit, cut across. G, seed. (Karsten.) bowl of the familiar coconut dipper. The shells of various gourds (Fig. 2G5) play a most useful part as vessels for holding liquid or storing food, in the domestic economy of many regions. Finally, may be mentioned the vegetable ivory (Fig. 2G6) which is a seed-food that takes the form of nearly pure cellulose. Large quantities of these seeds are imported and used in place of ivory or bone for umbrella handles, PSEUDO-WOODS 277 knobs, buttons, balls, and various other small articles of turnery. For the most part, pseudo-woods, although sometimes Fig. 267. — Cork Oak (Quercus Suhcr, Beech Family, Fagaccce). A, fruiting branch. B, twig with staminate flower-clusters. C, staminate flower. D, pistillate flower. (Redrawn after Schneider.) — Tree growing 15 m. tall; bark thick and spongy; leaves whitish, hairy beneath; flowers yellowish; fruit brownish. Native home, Southern Europe, and Northern Africa. locally important, are of comparatively small use and need not here be further discussed. 278 INDUSTRIAL PLANTS Fig. 268. — Cork Oak. Wedge of trunk cut across to show wood, with strong pith-rays and annual rings, and the thick bark consisting of the outer "virgin cork" (light colored) and the inner "cork mother" (dark colored). (Figuier.) Fig. 209. — Harvesting Cork. (Figuier.) CORK 279 75. Cork is the light, waterproof, compressible yet elas- tic material forming the outer bark of the cork oak (Figs. 267- 269). Like true wootl it is built up of annual layers formed by a cambium. It differs from wood in having the inner layers the younger, in being non-fibrous, and in containing about 70-80% of a mixture of waxy and tallow-like sub- stances which is known as subcrin. Very many plants pro- duce cork in their outer parts, but only the cork oaks form masses sufficiently large to be of economic use. The imperviousness to water, the elasticity, and the firm- ness of cork, upon which its economic value mainly depends, render it in the first place useful to the tree as a protection for the tender inner l^ark where processes of vital importance are carried on. Since these processes cannot proceed without free access of air the thick cork layer is found to be pierced by numerous breathing channels extending radially to the surface. Besides these channels rifts naturally occur in the outer bark as it is stretched by the increasing bulk of the wood within, and by the new layers of bark. In the 5'oung tree the first few layers of cork are compara- tively thick while those formed later are only about 1-2 mm. in thickness and soon become so brittle and so badly cracked as to be unfit for finer uses. Such inferior cork, suitable only for fuel, packing, fish-net floats, rustic work in conserva- tories, and the like, is all the tree ever produces if left undis- turbed. But in cultivation when the trees are from fifteen to twenty years old all of this "virgin cork," as it is called, is cut away, great care being taken not to injure the tender part within known as the "cork mother" because it includes the cambium. The effect of this operation upon the tree is in every way beneficial. Henceforth the cork produced is more abundant, softer, and more homogeneous; the breathing channels are farther apart; and the cracks become far less troublesome. For a century and a half or even longer, at intervals of eight to fifteen years, slabs of fine cork 5-20 cm. thick are peeled from the trunk in the manner illustrated (Fig. 269). The harvesting takes place in summer when the inner bark adheres most firmly to the wood. After l^eing stripped from the tree the slabs of cork are scraped so as to 280 INDUSTRIAL PLANTS clean the outer surface, are then flattened under pressure with the aid of heat, and finally tied in bundles for shipment. By far the most important use of cork is for stoppers. It is estimated that the daily consumption amounts to twenty million. Cork stoppers are cut either by hand or by ma- chinery. Large flat corks have to be cut so that the channels pass from top to bottom. Such corks require, therefore, the use of some sealing material such as wax, to make them impervious. Smaller corks are cut so that the channels go from side to side and hence are air-tight without sealing. In the cutting, about half the material, or more, becomes waste chips. So valuable are the properties of cork, how- ever, that even in this form it may be utilized in important ways. Thus, pulverized and mixed with rubber or with boiled linseed-oil it forms when spread on canvas a floor cover- ing at once durable and sound-deadening. Coarsely ground cork serves well on account of its softness and elasticity as packing for fruit, especiall}' grapes; and, when glued to paper forms a safe wrapping for bottles in transportation. The same remarkable properties make masses of cork most effective buffers for vessels. In the form of thin sheets it has long been used as a material for insoles and hat linings. The lightness of cork has especially recommended it for artificial limbs, handles, net floats, and life-preservers; while the uni- form texture and the ease with which it may be shaped have made it valuable to model makers and even to turners and carvers. Although cork was known to the ancient Greeks and Romans, and there is record of its use by them for the soles of shoes and as stoppers for wine vessels, it has been generally used only within the last few hundred years. 76. Elastic gums, including india-rubber or caoutchouc ^ and gutta-percha,- are tough, more or less elastic and water- proof solids which separate as a curd from the milky juice of a number of tropical plants. Small quantities of caoutciiouc are present also in many of our native plants having a milky juice, but the amount is ' Pronounced koo'ohuk. - Ch pronounced as in church. ELASTIC GUMS 281 much too small to be of any economic significance. The use of this juice to the plant is not altogether clear; but from the fact that it flows readily from a cut and after a little while hardens upon exposure to the air, the conclusion seems war- ranted that it serves in part at least as a ready means of Fig. 270. — Brazilian Rubber-tree {Hcuea fjuyunensin, Spurge Family, Euphorbiacecr) . A, flowering branch. B, part of flower-cluster. C, staminate flower. D, same with calyx removed. E, pistillate flower, with calyx removed. (Berg and Schmidt.) — Tree growing 20 m. tall; leaves thin; flowers inconspicuous; fruit somewhat fleshy. Native home, Brazil. covering wounds promptly with a waterproof protection against agencies of decay. One of the most important American sources of caoutchouc is the Brazilian rubber-tree (Fig. 270). Long before the coming of Europeans the South American Indians made use 282 INDUSTRIAL PLANTS of crude rubber for various articles including water-vessels, shoes, and torches. Similai- prehistoric use was made bj^ the East Indians of the product they obtained from the india- rubber tree (Fig. 271) which yet remains one of the more important Asiatic sources of this remarkable substance. Simple, primitive methods of obtaining the raw material are still practised very generally by the natives of to-day who in various parts of the world collect the rubber which is ex- FiG. 271. — India Rubber-tree (Ficuti clasticn, Mulberry Family, Moracece). Tip of branch showing leaves, the 5'oungest unfolding and still partly enwrapped by the protective stipule-case. (Original.) — ^Trec growing 30 m. tall; leaves thick and glossy; flowers similar to those of the fig (see page 102); fruit fig-like, greenish-yellow. Native home. Tropical Asia. ported to Europe and America for manufacture. First, ax cuts are made in the bark of a good-sized tree in such a wa}^ that the milk whicl; flows from the wounds will run into little cups so placed as to receive it. The collector on his rounds empties the contents of these into a larger vessel which he finally carries to where the milk is to be curdled. The separation of the caoutchouc from the whey-like part of the milk is accomplished variously; as for example, by mere exposure to th(^ air, or by the addition of water or vari- ous salts; but the best rubber is obtained by the process of smoking as practised in Brazil. Over a smoky fire, made by burning Brazil-nut shells or certain palm seeds, the operator holds the broad end of a clay-covered paddle which has been dipped in the fresh milk, and turns it slowly till an even layer ELASTIC GUMS 283 of the rubbery curd has set. Then he dips the paddle into the creamy hquid again, and repeats the operation till suc- cessive layers form a cake of consideral^le thickness. The cake is then cut from the paddle, and hung up to dry until firm enough to pack for transportation. Crude rubber comes into the market also in the form of sheets, balls, or masses of various shapes; and is often mixed with a con- siderable quantity of clay, bark, and other impurities. Rubber was first made known to Europe in the report of Columbus' second voyage, where the statement occurs that the Indians were found playing with elastic balls which bounced better than the "wind balls " of Castile. It was not, however, till after the middle of the 18th century that this elastic material came much into use. For many years it was scarcely more than a curiosity, serving in a practical way for little else than to rub out pencil marks. From this circum- stance it gained the name "rubber" and was called "india- rubber" because of its importation from the West Indies. Caoutchouc did not come from Asia till much later. As the unique properties of rubber — its unequaled elas- ticity combined with its great imperviousness to moisture — became more fully realized, effort was made to bring it into wide use. Thus, it was manufactured into elastic w^ebbing, overshoes, waterproof garments, and various impervious fabrics. Such goods became popular for a while, but their use was much restricted by the fact that the best rubber ob- tainable was apt to harden and crack in cold weather, and to soften or grow stickj^ in summer. Moreover, it was found that unprotected surfaces of pure rubber adhere; and that articles made of it were often worthless after a few months keeping, and were ruined by contact with oils. Much futile effort was expended to remedy these defects. Finally in 1844, Charles Goodyear, an American, announced his discovery that mixing a little sulphur with caoutchouc, and subjecting it to con- siderable heat, produces a substance that is even more elas- tic than pure rubber, is unchanged by any temperature be- tween — 20° and + 180°C., is less affected by oils or other solvents of the unchanged caoutchouc, does not become adhesive, and keeps well. This process of combining sulphur 284 INDUSTRIAL PLANTS with caoutchouc is called vulcanization. By using much sulphur and a high degree of heat hard rubber or vulcanite is produced. The discovery of vulcanization revolutionized the rubber industry. Not only were the old uses greatly extended but new uses for rubber have so multiplied that caoutchouc now ranks among the most important products of the vegetable kingdom. The elasticity of soft vulcanized rubber makes it invaluable in various articles of dress, for many surgical purposes, for elastic bands, solid or pneumatic tires, for various parts of machines, and for rubber balls, toys, and in- numerable other articles of minor use. Its imperviousness to water and air, combined with its flexibility, render it of greatest service for waterproof garments or coverings, sub- marine diving-dresses, flexible tubes or hose, water-bottles, air-cushions, life-preservers, portable boats, etc. Hard rub- ber takes a high polish and is very resistant to the action of acids and other corrosive fluids. Therefore it makes the best possible material for photographer's developing trays, certain parts of fountains pens, telephones, surgical instru- ments, etc., while it is a most excellent and inexpensive sub- stitute for horn or shell in such articles as combs and handles. Both vulcanite and the softer vulcanized rubber are exten- sively used for insulation in electric work. Pure rubber on account of its remarkable adhesiveness is an indispensable part of the best surgeon's plaster, and of the rubber tape used in repairing bicycle tires and in electric wiring. The curious erasing power of rubber, whether pure or vulcanized, is possessed by no other substance to anything like the same degree; hence one of its earliest uses still remains one of the commonest and most important. Caoutchouc as a raw material bears, as we have seen, some- what the same relation to the milky juice of plants that cheese bears to the milk of animals. That is to say, it sepa- rates from the fluid part as curd from whey, and becomes solid by drying. Chemically, however, caoutchouc is quite different from the proteid of which cheese mainly consists. Pure caoutchouc is a hydrocarhon; in other words, it contains only hydrogen and carbon in its composition. Commonly ELASTIC GUMS 285 associated with it are various substances, regarded as im- purities, among which are certain resins. These resins are beHeved to be derived from the caoutchouc through oxida- tion since they vary considerably in amount and differ chem- ically from the hydrocarl^on merely by containing oxygen. Such compounds are appropriately called oxidized hydro- carbons, and are distinguished from carbohydrates by the fact that the oxygen and hydrogen they contain are not in the proportion of HoO. The distinctive characteristic of rubber is its extreme elasticity. A curious result of this is the heat developed when a piece of it is stretched. Thus a sudden Avarmth is perceptible when a rubber band is (juickly stretched in con- tact with the lip. On account of this property means have to be taken in the manufacture of rubber to prevent over- heating when large masses are vigorously worked. Gutta-percha differs from india-rubber in being very firm and comparatively inelastic at ordinary temperatures, though at about 50°C. it becomes highly elastic and plastic. It re- sembles caoutchouc in flexibility, toughness, poor conduc- tivity of heat and electricity, imperviousness to moisture, insolubility in dilute acids and in alcohol, and solubility in oil of turpentine, chloroform, naphtha, carbon bisulphid, etc. Unlike caoutchouc, however, gutta-percha is unaffected by fixed oils. In chemical composition gutta-percha consists like caout- chouc, of a hydrocarbon similarly associated with resinous substances presumably derived from it by oxidation. Unless well purified soon after being collected the change into resin may go so far as to make the Avhole mass worthless. Gutta-percha is obtained from several different species of trees all closely related to the taban-tree (Fig. 272) which was the original source. All are confined to the region of Sumatra and Borneo. Owing to the foolish practice of felling the trees to obtain the milky juice, what was for many years the main source of supply is now destroyed. More conserva- tive methods of tapping, similar to those already described for caoutchouc-milk, give a continuous yield for many years. It has been also found that gutta-percha of the finest quality 286 INDUSTRIAL PLANTS may be extracted from the leaves by using solvents. In separating the solid from the liquid part of the milk obtained by tapping no special means are necessary. A hard "curd" soon forms. After removal of the worst impurities (some- times facilitated by boiling) the raw material is pressed into cakes or lumps and is then ready for export. Fig. 272. — Taban-tree {Palaquiuin Gutta, Sapodilla Family, Sapotacece). A, flowering twig. B, young fruit. C, flower. D, ripe fruit. E, F, seed. (Burck.) — Tree 13 ni. tall; leaves rusty-hairy beneath; flowers white; fruit fleshy. Native home, Malaysia. The general use of gutta-percha dates only from about the middle of the 19th centur}'. It was first brought j:)rominently into notice by Dr. W. Montgomerie, an English surgeon stationed at Singapore. He found the natives using this extraordinary material for ax handles, sword hilts, and the like. This suggested to him important uses for it in surgery RESINS 287 and various industrial arts; and, thanks to him, manufac- turers soon came to reahze that it was better adapted for certain purposes than any other substance. Among the more important or famiUar applications of gutta-percha may be mentioned its use as waterproof ma- terial in boot-soles, and as cement for leather, etc., its use for piping, for speaking tubes, various surgical appliances, golf balls, and molded ornaments. Its most important use is as insulating material for electric wires, especially cables. The great Atlantic cables and other submarine or subter- ranean electric lines, upon which modern civilization so much depends, owe their successful operation largely to the gutta-percha used to cover the wares and so protect them and at the same time prevent serious leakage of electricity. 77. Resins, like elastic gums, are derived from liquids exuded by plants, and serve as a protective covering for wounds. The common resin obtained from the pitch or turpentine of pines is a familiar example. More or less fluid at first, owing to the presence of volatile oil, the resinous sap solidifies on exposure to the air, partly through evaporation of the volatile constituent and partly through its oxidation. Finally it may become hard and brittle. In this condition resins resemble various gums. But true gums, as w^e have seen, are either soluble in water or absorb it indefinitely; while they are insoluble in ether, alcohol, carbon bisulphid, and oils. Resins, on the contrary, are insoluble in water; but are mostly soluble in the other liquids mentioned, at least when hot. Sometimes a gum and a resin are intimately united, forming what is knowm as a "gum-resin.'" Such a material is asafetida, which we have already studied. The name ''gum" is also applied commercially to gum-resins, and resins, and even to rubbery materials; it is most con- venient, however, to restrict the term as indicated above, except for ''elastic gums" from w^iich no confusion is likely to arise. When a considerable amount of volatile oil is asso- ciated with a resin the mixture (commonly of a honey-like consistency as in the turpentine of pines and firs) is distin- guished as an oleoresin. Resins are ahvays mixtures of sev- eral different oxidized hydrocarbons which agree in being 288 INDUSTRIAL PLANTS poor in oxygen and ricli in hydrogen and carbon, very in- flammable, and, from their laige proportion of carbon, burn- ing with a sooty flame. More or less resinous material is contained in the great majority of plants, and in many cases it is abundant and valuable for use industrially. Rosin and copal, which are among the most important resins, will serve as typical ex- amples. Rosin is so much the most widely known of resinous ma- terials that it is commonly called "resin" as if it w^re the only substance to which that name could apply. Chemicall}' it is known as colophony. It is one of the products obtained by distilling turpentine. What is properl}- called turpentine as already stated is the oleoresin which flow^s from wounded surfaces of pines and similar cone-bearing trees. When this is distilled the volatile parts that pass over and are con- densed form the familiar oil or spirits of turpentine, while the residue is rosin. The largest quantities are produced in our Southern States. Rosin is used as an ingredient in com- mon varnishes, is combined with tallow in cheap candles, and is extensively used in the making of yellow soap, inferior kinds of sealing-wax, and various cements. In shoemaker's wax and certain medicinal plasters and ointments it enters as an important part. Musicians depend upon it to rosin the bows of stringed instruments, tin-men and plumbers use it as a flux in soldering, and it serves many other purposes in the industrial world. Its property of generating, when vigorously rubbed, that sort of frictional electricity called "resinous " has led to the use of rosin in certain forms of electric apparatus for experimental purposes. Copal is a name applied rather indefinitely to a large variety of resins without much in common to distinguish them, but as strictly defined it is understood to include only such as occur naturally in hard masses resembling amber in appear- ance, and like that substance melting and dissolving only at a comparatively high temperature — a process requiring special precautions to prevent the resin and the solvent from catching fire. These resins make the best varnishes, and that is their main use. The botanical origin has long been INDUSTRIAL PLANTS 289 Fig. 273. — Courbaril-tree and Zaiiziliar f'opal-tree {Hymcmea Courbaril, and Trachylobium Hornemannianum, Pulse Family, Leguminosae). A, flowering branch of courbaril-tree. B, pistil and base of flower, cut vertically. C, part of fruit. G, part of flower-cluster of Zanzibar copal-tree. H. pistil and base of flower, cut vertically. ./, fruit. K, seed. L, same, cut across. (Taul)crt.) — Courbaril-tree 16-20 m. tall; leaves smooth; flowers white; pod filled with a sweet, mealy pulp. Native of tropical America. — Zanzibar copal-tree of considerable height; leaves with translucent dots; flowers white; pod leathery, not opening. Native home, Tropical Eastern Africa. 290 INDUSTRIAL PLANTS uncertain, but it is now known that the finest copal of the East is a product of the Zanzibar copal-tree while the best South American copal is from the nearly related courbaril-tree (Fig. 273). The difficulty of tracing the prod- uct to its source arose from the fact that the best copal is dug by the natives out of the earth often in tracts of country from which all plants that could have produced it have dis- appeared. The hard resin, sometimes covered by an ac- cumulation of three or four feet of soil, is all that remains to show the former existence of copal-trees at that place. It is a fossil. The happy accident of finding leaves, flower-buds, and flowers embedded in masses of Zanzibar copal, finally gave the last link in a chain of evidence connecting the resin with the species which produced it. The South American copal is found embedded in the earth at the base of courbaril- trees, and often contains bits of courbaril-bark. When the resin exudes from the tree and solidifies it is still too soft to be of commercial value; only the slow process of time, perhaps centuries, can bring it to that state of almost glassy hardness which renders it indispensable for making the most durable varnish. 78. Coloring matters of some sort are almost universally present throughout the vegetable kingdom. In many cases they can scarcely be supposed to be of any benefit to the plant which produces them but must be regarded as merely waste products of the plant's activitj^ This is very com- monly true of the vegetable coloring matters used in the in- dustrial and the fine arts as dyestuffs, pigments, inks, or the like. Such substances have been used from the remotest an- tiquity. In recent times, however, vegetable dyestuffs have come to be very largely replaced by various artificial com- pounds such as the well-known aniline dyes prepared by chemists from coal-tar. From among the vegetable pig- ments and dyestuffs that are still of importance in the arts gamboge, indigo, logwood, lampblack, and tan-l)ark ma}- be selected as typical and famihar examples. Gamboge is a gum-resin obtained from the Siamese gamboge- tree (Fig. 274) and other Asiatic species of the same genus. The resinous material flows from the bark through cuts, COLORING MATTERS 291 and is collected in hollow joints of bamboo. In these it hardens into cylinders, which, after they are removed for export, are found to bear the marks of the curious receptacle. Gamboge mixes readily with water, and largely dissolves in oils and in alcohol. For this reason as well as for its bright transparent yellow color it is highly valued by artists as a pigment. It is widely used also to impart a golden tinge to Fig. 274. ^Siamese Gamboge-tree (Garcinia Hanburyi, Gamboge Family, GuttifercB) . Branch with pistillate flowers and fruit; a, pistillate flower; h, staminate flower; c, stamens; d, pistil surrounded by rudimentary stamens; e, pistil;/, same, cut vertically; g, ovarj% cut across. (Baillon, Hanbury.) — Tree about 18 m. tall; leaves glossy; flowers yellowish; fi'uit cherry-like, reddish brown. Native home. Southern Asia. varnish intended for certain purposes, especially in lacquer for metal work. Indigo has been called the "King of Dyestuffs" in recogni- tion of the permanency and strength of its deep blue color, and the supremacy it has maintained over all rivals from the time of its first use in India thousands of years ago even to the present day, although an artificial indigo is now coming into use. Curiously enough the blue coloring matter is not present as such in indigo-plants. It is derived from a sub- 292 INDUSTRIAL PLANTS stance called indican (CogHsiNOiy) which is extracted by water from the leafy shoots, and, under the influence of an enzym which accompanies it, gives rise to a compound re- sembling glucose and to indigo blue (CicHioNoO:). A sub- stance which thus decomposes into a sugar and some other compountl is known as a glucoside. Indigo blue is insoluble in water and can therefore be separated along with certain impurities by filtration. The pasty mass retained is dried in cakes to form the indigo of commerce. The insolubility of indigo blue in water presents a peculiar difficulty to its use as a dye, yet at the same time gives it a great advantage when once it is incorporated with a fiber. The difficulty is overcome by taking advantage of the fact that indigo blue may be readily changed (in various ways which increase the proportion of hydrogen) into a colorless substance called indigo white (CieHijNoOo) which is soluble in dilute alkaline solutions and has the fortunate property of quickly changing back to indigo-blue on exposure to the air. The means com- monly employed by dyers to change the indigo-blue is to add indigo to vats containing lime-water in which bran or mo- lasses or some other substance is undergoing fermentation. When the indigo is all transformed and dissolved, a piece of white woolen or cotton soaked in the solution and then exposed to the air soon takes on a permanent blue color. A considerable number of plants have been found to con- tain indican, and several different species are cultivated in India and other warm countries for the manufacture of indigo. Of these plants the most important one is the dyer's indigo shrub (Fig. 275). Logwood is obtained from a small Central American tree (Fig. 276). It is exported in the form of logs from which the sap-wood has been removed. The coloring matter which it yields, is, like indigo, not present in the living plant but is derived from a colorless glucoside called hematoxylin (CieHiiOe) which in turn readily oxidizes to form the deep violet-purple compound known as htrmatein (CicHjaOe). It is interesting to observe that this transformation involves the loss of two atoms of hydrogen just as does the change of the white indigo into the blue. Unlike indigo, however, COLORING MATTERS 293 Fig. 275. — Dyer's Indigo Shrub (I ndigofera tinrtorid. Pulse Family, Le- guminosce). Flowering branoh; a, flower, enlarged; h, standard (upper- most petal), back view; c, wing (side petal), inner view; d, e, keel-petal, inner and outer views;/, flower with corolla removed; g, pistil. /;, fruit, natural size; i, seed; k, same, cut verticallj-. (Berg and Schmidt.) — Shrub growing 2 m. tall; leaves downy beneath; flowers reddish yellow, fruit dry. Native home, Southern Asia. 294 INDUSTRIAL PLANTS logwood of itself does not make a permanent dye. It requires the use of a mordant, that is to say, some substance such as a salt of iron which fixes the dye upon the fabric. Thus used it makes one of the best blacks for wool or cotton. In com- bination with iron, etc., it is used also A\ddely in the manu- facture of writing inks. Lampblack is the finely divided carbon deposited from the smoke of rosin or oil burned with slight access of air in Fig. 276. — Logwood-tree {Hwmatoxylon campecheanum, Pulse Family, Lcguminosw) . A, flowering branch. B, flower. C, same, cut verti- cally. D, pod. (Taubert.) — Tree about 8 m. tall; leaves smooth; flowers yellow, fragrant; fruit dry. Native home, Tropical America. a special chamber. It is used extensively in the making of printing-ink, and forms the basis of incha-ink and of various black pigments used in painting, leather-finishing, and the like. Lampblack is one of the most important of coloring matters. Tan-bark is obtained from many trees, including hem- lock (Fig. 263), oak (Fig. 243), willow (Fig. 228), chestnut (Fig. 24), larch (Fig. 259), and spruce (Fig. 260), which are rich in tannins. These substances, as already explained in sections 57 and 60, are astringents which are present in OILS 295 various parts of many i)lants, and agree in forming an ink- like product when combined with an iron salt. Though chemicahy more or less diverse they mostly resemble indican and hsematoxylin in being glucosides, and are believed to be usually waste products of the plant producing them. A property of tannins which renders them especially valuable to the dyer is that thej^ are readily absorbed in solution by cotton, linen, and silk, and will then precipitate various dyes within the fiber, thus serving as a mordant. But the chief •property which gives industrial importance to plants rich in tannins is the power which these substances have of so combining with animal skins as to render them permanently pliable and resistent of decay. Hence it is that a hide soaked, under proper conditions, in an extract of tan-bark becomes leather. At the same time, the staining powers of the tannin and associated substances may be taken advantage of to impart a strong color to the product. 79. Oils, whether fixed or volatile, are very generally pres- ent throughout the vegetable kingdom; and, as we have alread}^ seen, they are often of much economic importance as food or flavoring, and in medicine. They are of scarcely less value in the industrial arts, immense quantities of dif- ferent vegetable oils being consumed in the manufacture of paints, printing-ink, varnishes, soaps, and perfumery, and as lubricants and illuminants. As vehicles for j)igments fixed oils are selected which not only will hold the particles of coloring matter in perfect sus- pension, and so make it easy to spread them evenly over a surface, but which also will harden promptly when thus spread into a film exposed to the air. Oils which harden in this way are called drying oils although the change which takes place depends not upon the evaporation of a volatile solvent, as in the drying of certain varnishes, but upon the absorption of oxygen which changes the oil into a varnish-like substance. Linseed-oil, which is obtained by pressure from the seeds of flax (Fig. 217), is the one most widely used by painters. Its "drjdng" qualities are much improved by boiling. For use in printing-ink the oil is boiled until it is very thick. Other drying oils which are somewhat superior to linseed-oil are 296 INDUSTRIAL PLANTS poppy-oil, from the seeds of the opium poppy (Fig. 172), and nut-oil, from the kernels of the EngUsh wahiut (Fig. 27). These being comparatively expensive are reserved for fine painting. Linseed-oil is invaluable also as a solvent for copal and other resins, with which it unites at a high temperature to form the highest class of varnishes. Entirely by itself it is used extensively to give an attractive "oil finish" to wood- work. In certain varnishes the volatile oil or spirits of tur- pentine, known commonly to the trade as ''turps," is the solvent used, and is likewise indispensable to painters as a means of thinning their colors. Any of the fixed oils combined with an alkali makes soap. When potash (or lye from wood ashes) is used soft soap is formed; hard soap being ^nade with soda. Chemically th(> fixed oils are mixtures, in various proportions, of compounds called glycerides. A glyceride is so called because it consists of glycerin (the familiar sweetish substance soluble in water) combined with an acid. Linoleic, oleic, and palmatic acids are among the most important in vegetable oils. The gly- ceride of linoleic acid, called linolein, forms 80% of linseed- oil, and gives to this and to other drying oils their peculiar power of hardening by oxidation. Olein, the glyceride of oleic acid, is the main constituent of olive-oil. It is liquid at ordinary temperatures and becomes rancid by oxidation. Palmatic acid forms a glyceride, palmatin, which is not liquid at ordinary temperatures. It is the main solid constituent of coconut and other palm-oils. When any fixed oil is mixed with an alkali, the glycerides present are decomposed each into its peculiar acid and glycerin, and the acids unite with the alkali to form soap, leaving the glycerin free. Inferior grades of linseed oil and other cheap oils are used for soft-soap. Oil from the olive (Fig. 113) is used extensively for castile, and other fine toilet soaps. Other hard soaps of various grades are made from " cocoa-butter " (see section 39), and oils from coconut (Fig. 36), cotton-seed (Fig. 215), peanut (Fig. 32), and almond (Fig. 31). To give an agreeable odor to soap a large variety of volatile oils arc introduced during the process of preparing the product FUEL 297 for market. The oils of winfergreen (Fig. 147), marjoram (Fig. 137), coriander (Fig. 143), thyme (Fig. 134), caraway (Fig. 140), and many others are thus used to a greater or less extent. These same volatile oils enter also into th(,' manufacture of 'perfumery; and for this purpose many other volatile oils are more or less in demand, as, for example, the oils of nutmeg (Fig. 129), allspice (Fig. 123), sassafras (Fig. 160), peppermint (Fig. 146), spearmint (Fig. 135), orange-peel and orange- flowers (Fig. 106), and the oil distilled from the wood of red cedar (Fig. 261). It is to the fragrant oil obtained from the bark of white birch (Fig. 254) that the characteristic odor of Russia leather is due. None but fixed oils can serve as lubricants; and of these, only the non-drying ones are suitable. The vegetable lubri- cants most extensively employed are (1) olive-oil, used for this j^urpose mostly in southern European countries where a sufficiently good quality may be obtained at a low price, (2) rape-oil from the seed of a variety of turnip grown widely in northern Europe and India, and (3) cotton-seed oil used largely in this countr}-. As illuminauts vegetable oils have not to-day the impor- tance they had before the introduction of petroleum lamp-oil and paraffin candles. Nevertheless, large quantities of vegetable illuminants are still consumed, especially in regions where mineral or animal oils are comparatively expensive. Almost all the fixed oils in common use for other purposes have served for burning, but the non-drying oils are pref- erable. Olive, peanut, and 7'ape oils, which are all rich in olein, are among the best. Palmatin, as we have seen, is an important constituent of coconut-oil. This substance sepa- rated from the more fluid parts of the coconut-oil and other palm-oils affords an excellent material for candles. 80. Fuel, whether as a source of heat or of power, being indispensable to the carrying on of almost every industry, and being also a necessity for steam-transportation, for the heating of buildings, and for cooking, it is plain that civiliza- tion could not have developed as it has, nor could it possibly go on, without this source of heat. 298 INDUSTRIAL PLANTS Anything which burns readily in the air will serve as fuel; and, indeed, various sorts of refuse are thus utilized: for ex- ample, wheat straw is made to run steam threshing-machines, and the crushed stalks of sugar-cane are used in the boiling of the juice. But, in general, wood, peat, and coal, and their products, charcoal, coke, and illuminating gas, are the fuels most extensively used. Wood is the most used of all fuels. All woods when per- fectly dry consist of nearly 99% of combustible material and about 1% of inorganic matter which remains as ash when the wood is burned. Air-dry wood contains about 25% of water, and in green wood it may be as much as 50%. This water reduces the fuel value not onl}^ as taking the place of combustible substances but also as using up the heat necessary for its evaporation. Hence the economy of well- seasoned fire-wood. The value of different fuels may be conveniently compared when stated in terms of the amount of water which a unit Aveight will evaporate. Thus, green wood is found to yield enough heat to convert about twice its weight of water at 100 C. into steam; air-dry wood about three and a half times; and perfectly dry wood over four times its own weight. So far as chemical composition is concerned soft woods should yield on burning about the same amount of heat as hard woods of equal dryness. In practice, how- ever, considerable differences are found, depending in part upon the ease with which complete combustion ma}' take place, as shown by tiie amount of smoke, and in part upon compactness of structure, and so forth. Wood as being a flaming fuel is especially well adapted for heating surfaces of large extent, as in the boilers of steam-engines. The small amount and the soft crumbly nature of its ash give wood a further advantage over peat and coal. Peat consists of the more or less carbonized and compacted deposits of vegetable substances which accumulate in bogs and marshes, and, in the presence of water, slowl}' decompose. Peat-bogs form chiefly in northern countries. Near the sur- face they consist largel}^ of moss like that shown in Fig. 227 with which, however, a number of other plants are found growing. In the deeper layers that have been buried for a FUEL 299 o -rj ^^ « OJ > O ^-, a; o ,Tt<_, u o M u -a o =« ™i3 p-S ^-^ c3 S a- 5 Ml a ■ro t!x 2.*^ +^ OO^ O — .g ..M "2 SCO o3i; ■^ 2^ 2 S t 3 T3 > S^ S S— c- C 03 -O ff 3+^ C S O tu 3 ■D «S.2 +^ MO- ^ o a u o 3 0; O^ o 3 O c^ ^ P-i O O M C S- -OX M o Wl t- ,« 5 < S i; =J fj^ 300 INDUSTRIAL PLANTS long period of time, the material is so transformed as to be like a soft, brown coal. In regions where wood is scarce peat is highh^ valued as a fuel. It is commonly more bulky than wood, and has from 5 to 15 times as much ash. Its heating power is about the same. Coal, like peat, consists of the decomposed and compacted remains of plants. It differs from peat principally in being harder and more completely reduced to carbon. But peat passes into coal by insensible gradations so that none but an arbitrary line can separate them. The coal with which we are most familiar may be regarded as a peat-like material of very great antiquity, — so ancient that the plants from which it was formed have been extinct for many ages. Some idea of the appearance of certain of these coal plants may be gained from Figs. 277, 278. In comparison with wood and peat as a fuel, coal has the advantage of possessing greater com- pactness and more poAver of heating. It will convert into steam about 7 to 9 times its own weight of water. The most objectionable features of coal are its large amount of troublesome ash, which often interferes with good combus- tion, and its offensive smoke, which is excessive from soft coal. Charcoal burns without flame or smoke, and has over twice the heating power of wood, or as much as the average coal. It is produced mostly by smothered combustion of billets of wood, commonly arranged in conical piles, and cov- ered with earth. When wood is subjected to dry distillation creosote, wood-alcohol, and other volatile compounds pass into the condenser, leaving charcoal in the retort. The charcoal produced at the highest temperature yields most heat when burned, and is therefore of most use in metallurgy; that produced at as low a temperature as possible is the most inflammable and thus the most suitable for mixing with niter and sulphur to make gunpowder. Coke bears somewhat the same relation to coal that char- coal does to wood. It is similarly obtained by smothered combustion in covered piles, or by heating in special ovens or retorts. Like charcoal it is nearly pure carbon, and is used extensively in metallurgy and for other purposes where a FUEL 301 smokeless fuel is required. It was orif>inally a by-product in the manufacture of illuminating gas. Now it is manu- factured expressly for metallurgical purposes, the ovens being so constructed that the inflammable gases driven off are made to serve largely as a source of heat in the process. Fig. 278. — Fos.sil remains of a giant club-moss {Lcpidodendrun up., Scale- tree Family, Lcpidodendraceoe) . From the coal period. (Baillon.) Illuminating-gas is made by subjecting coal or wood to a high temperature in a retort, and collecting and purifying the gas given off. For obvious reasons coal-gas has proved to be a most convenient fuel especially adapted for household use in large cities. The study of fuels leads one to think not only of the forests 302 INDUSTRIAL PLANTS of to-day and of bog-plants that lived p6rhaps hundreds of years ago, but in imagination one is led back to strange forests which disappeared from the earth many thousands of years ago and became turned to stone. Therefore, if we ask ourselves, Whence comes this material that men burn to get heat and power? the answer is. From the bodies of plants, some of which lived ages before the coming of mankind. And if we further ask. Whence comes the energy which all these plants have stored in their bodies, and left for us to set free? students of nature tell us. From the sun. That is to say, plants with fohage are the sunbeam-traps of our planet, and except for their marvelous ability to lock the energy of sunshine into the material of food and fuel, the life of the world as we know it would be impossible. How plants are able thus to store up sunshine, and why they do it, are questions to be answered only by the study of their processes of life. 81. Useful and harmful plants in general. From our study of some of the more important groups of economic plants We have learned not only that the very existence of the human race depends upon the vegetable kingdom but also that the progress of humanity at every stage has been profoundly influenced by the properties of plants and by man's knowledge of them. The needs of primitive man must have been met largely by wild plants. Through the cultiva- tion of plants, as we have seen, civilizations were developed in those regions where the most useful plants grew most abundantly. The desire for spices and similar luxuries led to the discovery of America. The vegetable products of the New World are now revolutionizing human life to the re- motest ends of the earth. Our brief study of vegetable foods, food-adjuncts, medi- cines, and raw products has shown that what we take from plants for our own use has often a similar use for the plants themselves, though sometimes the use is quite different; and in some cases, so far as we can see, the product is of no use whatever in the plant's economy. In other cases it has been found that sul^stances poisonous to us are also poisonous to the plants which produce them, just as the venom of cer- USEFUL AND HARMFUL PLANTS 303 tain animals may be fatal to themselves. Since, however, some of these plant poisons are among the most valuable of medicines, it is plain that no dividing line exists between harmful and useful plants. Judged in its relation to our welfare the same plant may be either useful or harmful accorcHng to what we do with it. Obviously, the more we know al)out their properties the less likely are we to suffer harm from plants, and the more likel}' are we to benefit by them. The student should understand clearly that in this book the aim is only to introduce beginners to the study of plants. Our purpose is merely to lay a good foundation for future stucUes which shall further advance general culture. There has been no intention of giving here a complete outline of economic botany. Accorchngh^, a great many plants of high economic importance have not been mentioned; and some of the chief uses of plants, and some of the most serious ways of their w^orking harm, have been passed over with bare mention, or have been ignored. Thus, in regard to the food of domestic animals but little has been said of the fod- der raised for them, and nothing at all of pasture plants upon which some of the principal industries of the world depend. The many plants which afford bees the material for making honey and wax, and those which serve as food for silkworms or other iasects of economic value have also been neglected. So also have we omitted reference to the plants which do great service in binding shifting sands that but for these sand-binders would devastate extensive areas: to those plants similarly used to prevent the washing away of soils; to trees set out as wind-breaks for protecting tender vegetation, as drainers of swamp land, or for shade and beauty; and to the innumerable flowers and foliage plants cultivated or collected for ornament. Likewise, among harmful plants neither weeds nor destructive parasites have been included. Not onl}' has our study neglected these groups of plants which especially affect the welfare of mankind but it has been forced to leave out of account some most extensive in- fluences which vitally concern animals in general. For ex- 304 USEFUL AND HARMFUL PLANTS ample, there is the influence of forests upon water-supply, by which is meant their action as reservoirs feeding the streams gradually in spring, thereby avoiding floods, and at the same time keeping back plenty for the dry season. Then, too, there is the im})ortant action of plants in soil- making, and the purifying influence of vegetation upon air and water whereby they are made to serve better the needs of animal life. All these various relations of plants to the life of the world, and to our own lives in particular, are as profitable and attractive matters of study as any that have claimed our attention; and the student will do well to learn all he can regarding them. It should be said, however, that many of these relations are best understood in the light of vegetable biology. Moreover, the student's pursuit of economic botany cannot well proceed much farther than we have here at- tempted to go, without his first acquiring such an elementary knowledge of systematic botany as the following chapters may help him to gain. CHAPTER VII CLASSIFICATION AND DESCRIPTION 82. Systematic classification. In Chapter I it was pointed out that the large number of plants which botanists have to study has made necessary some sort of classification or orderly arrangement into groups within groups. Plainly', ■ one of the chief requirements of such an arrangement is that it shall luring nearest together those forms which are most alike, while it separates proportionately those which differ more or less from one another. Hence, in general, the most useful classification is that which indicates most truly the degrees of difference and resemblance by its manner of grouping the objects classified. To construct a classification of plants which shall meet this important condition as fully as possible has long been one of the chief tasks of the science of botany. Indeed, so important has the solution of this great problem seemed to botanists that until comparatively recent times it has en- gaged their attention almost exclusively. From their labors has at last resulted a classification which, although still incomplete in certain parts, is yet wonderfully adequate in its main features; and whether we consider the vastness of the undertaking or the success already attained, we must recognize it as one of the greatest achievements of the human mind. By its means to-day the student is enabled to gain a wider and deeper knowledge of the world of plants than was ever possible to the most learned botanist of former times. In the remaining chapters one of our chief aims will be to advance toward a general idea of modern systematic botany. Thus far in our study of useful plants, it has been most helpful to arrange them according to their uses; and it was sufficient for our purpose to mention merely incidentally 305 306 CLASSIFICATION AND DESCRIPTION the family or other group to which ]3otanists assigned each plant under consideration, leaving the resemblances and differences thus indicated to be realized more or less vaguelj^ by the student. What was then vague we shall strive now to make more definite, and the student may be assured that very much of what he has been learning about economic plants will prove of service in the present study. 83. Early attempts at classifying. Perhaps the reader may ask why it is not sufficient for all purposes of study to classify plants according to their uses, somewhat as we have been do- ing. Such a method of classification was indeed employed by some of the earlier writers upon plants; and this was quite natural, since, as we have seen, they were concerned chiefly with plants in their relation to human welfare. But granting that every plant may be of some use (even though not yet discovered) we know that many are useful in more ways than one. Consequently, any classification according to uses would often have to include the same plant in several different groups. Moreover, the great majority of plants are not put to any special use, and affect our welfare only in the same general way as do the economic ones apart from their special uses. Hence, any attempt to classify all plants ac- cording to use would require us to have besides the economic groups, one general group that would include all plants; and in the subdivision of this group we should be face to face with the original problem. One of the earliest attempts to avoid this difficulty was a division into herbs, shrubs, and trees. This grouping accord- ing to size and general appearance was a step in the right direction, and for certain purposes is found to be a serviceable arrangement even to-day. Yet, aside from the objection that when applied to all known plants each group includes an enormous number of sorts, there is the further disadvan- tage that such a classification requires one to place in differ- ent groups plants which resemble one another more closely than they do any others of the group in which they are placed. Thus, for example, certain oaks which are nothing but shrubs would on that account be separated from all the other oaks which are trees; the same is true of willows and of manv ARTIFICIAL SYSTEMS 307 other genera that might be mentioned. Crude as this ar- rangement was, it afforded for many generations the best general classification of plants that anyone had to offer; and it was not until after the revival of learning in Europe, dur- ing the sixteenth century, that any important efforts were made to find a better waj'. 84. Artificial systems. An attempt was made to over- come the above objection regarding unnatural separation of sorts much alike, by calling the larger shrubs, trees, and the smaller ones, herbs, thus doing away altogether with the intermediate division. This, of course, lessened the difficulty in a way, but can hardly be sai'd to have removed it. To make smaller groups, these two were again subdivided according to differences observed in this or that part. Thus, some writers made subdivisions according to the shape or arrangement of the leaves; others according to the form of the fruit or seeds; others still, according to peculiarities of some part of the flower; and so on, each writer basing his system upon characters taken from one or two parts. Many attempts of this sort were made during the next two centuries. Some of these systems were decided improvements over the earlier classification, but even the most elaborate of them had the same fundamental weakness already pointed out in the arrangement according to size. We know that plants which chffer a good deal as regards a single part may be very much alike in all other respects, while plants much alike in a certain part may be otherwise very different from one another. For example, the fruits of the almond and the peach differ much in appearance when ripe, but otherwise an almond-tree and a peach-tree are almost exactly alike. On the other hand, the root of the beet and of the turnip are often of exactly the same shape, while the plants are strik- ingly different in all other respects. It is plain, therefore, that any arrangement of plants based upon a single character or very limited set of peculiarities, is bound to be unsatis- factory, because it cannot accomplish the chief purpose of a classification, namely, to group nearest together the sorts that are most alike. In a word, these systems failed chiefly because they are artificial, and so not well calculated to ex- 308 CLASSIFICATION AND DESCRIPTION press the resemblances and differences among plants as we find them in nature. On the whole, as we have said, these artificial systems served to advance botanical knowledge; although after a while the increasing number of them became a serious burden to all who studied plants. Any system, it was thought, if only used by all, would be much better than having to use so many. At last a practical way out of the increasing confusion was found by the clear-sighted Linnaeus who came to the rescue much as he had done in the matter of plant names. 85. The Linnaean system. The great need for some system which would be used by botanists in general, could, of course, be met only by a classification that was more convenient than any of those already proposed. Linnaeus was the first to see clearly that the necessary convenience could not be expected in his day from any attempt at a natural arrange- ment, for the plants to be arranged were as yet very im- perfectl}^ known. His predecessors had tried to produce a natural classification on an artificial basis, with results that were neither natural nor convenient. He aimed first of all at convenience, and to this end adopted a frankly artificial basis; yet in spite of this, as we shall see, his system proved to be more natural in many ways than any previously pro- posed. In the Linnaean system, the old division into herbs and trees was entirely abandoned; all plants were divided into twenty-four "classes," according to the presence, number, or form of certain essential parts (pistils) of the flower; and these classes were so grouped that all flowering plants were separated from those which have no true flowers. The latter constituted Class 24, Cryptogamia ^ or cryptogams, which includes all plants such as seaweeds, mushrooms, mosses, and ferns, that are either destitute of parts such as we find in flowers, or if anything corresponding to such parts are present they are hidden from our unaided sight. The other twenty-three classes include all plants in which floral parts essential to the formation of seed, are manifest, — such ' Cryp-to-ga'-miii < Gr. kyri/ptos, hidden. THE LINN.EAN SYSTEM 309 plants as are now often known as Phenogamia » or phenogams. Each class was again divided into several "orders" mostly according to the number, etc., of the other essential organs (stamens) of the flower. Under these orders Linnseus grouped all the genera and species of plants known in his day. The distinctions upon which Linnaeus depended were so easy to understand and remember, and afforded such a con- venient means of classifying any plant, that the sj'stem soon gained an immense popularity, especially in England, and led to a widespread study of plants. IMoreover, in tiis time, explorations in various parts of the world were bringing to light a great many kinds of plants and animals, previously unknown; and as Linnseus had also published a convenient classification of animals, most of those new discoveries were sent to him to name and classify. On the foundations so broadly laid systematic botan^^ progressed much more rapidly and better than ever before, and during more than half a century the system of Linnaeus remained practically the only one in use. We have said that although deliberately artificial, the Linnaean system was remarkably natural in many respects. This is shown in the separation of the cryptogamic from the phenogamic plants; also in the fact that the species of a genus were always kept together, and in the association of many of the genera into orders corresponding to certain of the families recognized to-day. To understand why this is, we must remember that plants which resemble each other in one particular have very gen- eralh^ other points of resemblance as well; hence, almost any artificial system is bound to be natural to some extent, and to what extent will depend on how far the characters chosen imply other points of resemblance. The reason why the Linnaean system was so natural, was that its founder had the sagacity to choose his characters primarily from the essential parts of the flower; for likeness in these parts in- volves a great deal of similarity in other respects. Thus, the ^ Phe-no-ga'-mi-a (written also Phsenogamia and Phanerogamia) < Gr. phaino, to be manifest; gamos, marriage: because the floral organs essential to the production of seed are manifest. 310 CLASSIFICATION AND DESCRIPTION possession of true flowers implies the formation of seeds, and this in turn generally involves an elaborateness of struc- ture in the plant as a Avhole far greater than is found in cryptogamie plants, which, as we know, lack true flowers and seeds; while among flowering plants it constantly hap- pens (as the reader has doubtlessly already noticed in such familiar examples as the apple, pear, and quince) that close resemblance in the form of the seed-producing parts of the flower goes with fundamental similarity in all other parts of the plant. With all these advantages it is no wonder that this re- markable system should have exerted the wide influence which it did; but after all it was too artificial to serve per- manently as a final solution of the great problem of sys- tematic botany. Thus, for example, the group with two stamens and one pistil includes such widely different plants as olive and sage, while sage is kept far removed from other mints because they have four stamens. No one realized more fully than Linnseus that his system was at best but a make- shift, fit only to serve the temporary needs of the science until botanists should be more extensively and more thor- oughly acquainted with plants than would be possible for many years to come; and he regarded his work only as a stepping-stone to the final achievement of an adequate clas- sification. 86. The natural system. As a contribution to the nat- ural system which he firmly believed would be developed in course of time, Linnaeus published a series of sixty-seven groups of genera which he called "natural orders." He con- fessed his inability to define these groups by giving characters which would apply to all the genera of an order, and at the same time serve to separate the orders one from another; and left it for future botanists to discover how far the groups he had suggested really express the fundamental resem- blances and differences found in nature. The fuller knowl- edge of later times has largely justified a good share of these groupings; not a few of Linnseus' natural orders are substantially equivalent to families recognized to-day, and have a place in modern classification often under the THE NATURAL SYSTEM 311 same or similar names. As examples may be mentioned the Palmce or palms, (iramina or grasses, Orchidece or or- chids, Cotnpositce or composites, Coniferce or conifers, and Filices or ferns. During the life-time of Linnaeus, the only other important attempt at a natural classification was made by Bernard de Jussieu, of France, who was a correspondent of Linnaeus, and was in charge of the royal botanic garden at Trianon. Here he grouped the plants as far as he could in natural orders, but he ])ublished nothing. In 1789, two years after the death of Linnteus, Antoine Laurent de Jussieu, nephew of Bernard, published a classification of genera under natural orders, one hundred in number. These were carefully de- fined by suitable characters, and thus constituted the first thoroughgoing attempt at a natural system. Not only were the genera grouped into well-defined orders, but the attempt was made to group the orders into higher and higher series, expressive of their degrees of likeness. On the foundation thus laid over a century ago the natural system now in general use has been slowly developing; the work of improvement is still going on, and more rapidly than ever before. Eventually the science of botany may boast of a systematic classification founded upon, and, in a way, expressing, a full knowledge of vegetable forms. Yet, as we shall hope to show in a future chapter, there are good reasons for believing that such an ideal classification will embody in very large part the distinctions at present recog- nized, or in other words, that the main features of a truly natural system are fairly well established. The next genera- tion of botanists will doubtless have the advantage of a far better classification, especially of cryptogams, than that in use to-day; but we may well believe that their classification will be essentially the same in general principle and in its main features as that now used. To develop the present system has been a gigantic task, beset with many difficulties; and before we can rightly understand the outcome of all this botanical labor, we must consider still further the diffi- culties overcome, lentil we have mastered certain of these ourselves we are not fitted either to appreciate or to use to 312 CLASSIFICATION AND DESCRIPTION best advantage the important results which botanists have achieved in systematic classification. 87. Technical description. One of the most serious diffi- culties with which the earlier botanists had to contend was the problem of giving one another a clear idea of what each had seen. It is plain that so long as they failed in this, their discoveries were of little consequence. At first sight it may seem a simple matter enough to tell what one sees, and be- ginners often wonder why botanists use so many peculiar words in their descriptions. "What is the reason," they ask, "that ordinary English is not sufficient for the purpose?" If the reader has ever attempted to use "ordinary English" in the way proposed, he will realize that it is far from easy to give a clear account of the peculiarities of a plant in that way. The result is much as when a landsman ignorant of nautical terms tries to describe the features of a vessel so that it may be recognized. Success may not be impossible, but such a method of going to work is at its best clumsy, roundabout, and misleading. It was largely because the early botanists had nothing better to use than the ordinary language of their day, that it often proved impossible for others to tell what the plants were that they had tried to describe. But little progress towards a satisfactory classification of plants could be expected as long as descriptions were so vague and incom- plete as to be largely unintelligible. Since an ideal botanical classification represents, as we have seen, the expression of all the resemblances and differ- ences among plants, its attainment must involve the use of words especially fitted to express unmistakably all the pe- culiarities that may be observed. Each part must have a special name, and the innumeraljle forms and features of each part must be indicated by simple words or phrases. Ordinary language has not been developed to serve any such botanical purposes any more than it has to serve similar nautical needs; hence, botanists have been forced to make a language of their own consisting largely of technical terms. 88. Early attempts at describing. Before the time of Linnoeus, the attempt was made by many botanical writers to avoid the language difficulty by the use of pictures to LINN^AN REFORM IN TERMINOLOGY 313 show what they meant, much as we have done in the fore- going chapters. A good picture is certainly to be preferred tO a description that is not understood; but a httle thought will show that pictures, however good they may be, cannot solve the whole difficulty. We cannot make a picture of a species, but merely of a single individual; and our conception of a species must be our idea of the features which all its individuals have in common. A number of pictures of dif- ferent individuals might convey more of this idea, but even then peculiarities perceptible only by touch, taste, or smell could be indicated only by words. Moreover, even features that may be represented in a picture generally need the help of words to point out what especially calls for attention; and when species are compared and classified one arrives at important general ideas which cannot be pictorially expressed. Add to these shortcomings the greater labor and expense involved in publishing pictures, and it becomes evident that verbal means are needed. For centuries, as we know, all learned works were written in Latin; consequently, it was from this language that the botanical terms were primarily taken. These were often common words to which a meaning was attached differing from the ordinary one, more or less, in its apphcation; or, sometimes new words had to be coined and this was fre- quently done by latinizing words or combinations of words taken from the Greek. As with the early attempts at forming systems of classi- fication, so in the development of a botanical terminology or technical vocabulary, different writers went about the matter in different ways; and such independence of action naturally led in this case also to a good deal of confusion. From this embarrassment of riches, which threatened to be a serious hindrance to further progress, Linnaeus, again, found the best means of practical relief, just as he did in the matter of classification and nomenclature. 89. The Linnaean reform in terminology. Being thoroughly familiar with the botanical writings of his predecessors, and endowed with a fine sense of fitness in language, Linnaeus was able to choose the best terms which had come into use, 314 CLASSIFICATION AND DESCRIPTION define them in a convenient way, and add others so far as necessary. The pubHcation of this carefully prepared vo- cabulary gave the necessary material for making botanical description henceforward an art, while in his systematic writings Linnaeus left examples of the art, well calculated to serve as models of excellence. In describing a plant his ideal was to state all that was necessary and nothing that was unnecessary to distinguish it from all other plants. Since the time of Linnceus, botanical terminology has been enriched and improved in various ways to meet the needs which have arisen with wider knowledge; but the art of describing plants still remains very largely what its first great master made it. Pictures are no longer deemed neces- sary to make up for vagueness of description; when it is possible to use them, their scientific value is much increased h)ecause what they lack may be supplied in words, and the significance of what is represented can be made plain. In- deed, to one familiar with the terms used, a complete bo- tanical description calls up so clear a mental picture of each part described, that a dra^ving sufficiently accurate for recog- nition might often be made even though no specimen of the plant had ever been seen. Surely this is a triumph such as ordinary language has never attained. 90. Terminology and nomenclature. Persons who have only a superficial acquaintance with botany are apt to think of it merely as a study of names, which hinder rather than help one in learning whatever botanists may know of general interest about plants. Doubtless the student of the fore- going chapters already feels that this is far from true; yet this false opinion conceals a truth which it will be worth while for us to consider. Special names and descriptive expressions of various sorts do occupy a prominent place in the scientific study of plants, and these botanical technicalities doubtless present a more formidable appearance than the special terms of most other sciences. Yet, paradoxical as it may seem, the very fact that botanists use these means of expressing themselves, makes it much easier for a beginner to arrive at an under- standmg of what they have to say, and so to a knowledge of TERMINOLOGY AND NOMENCLATURE 315 plants, than would otherwise be possible. The unusual fullness of their special vocabulary enables botanists to tell what they know in the fewest possible words and with least danger of being misunderstood. False ideas are the greatest hindrance to the pursuit of knowledge; and whatever will lessen the danger of these, especially to the beginner, is sure to save labor in the end. We have already seen (page 4) that the practice of hav- ing a double name for each species, instead of giving twice as much to remember as if the name of each sort were a single word, almost halves the burden upon one's memory that one-word names would impose. The ease ^vith which words are remembered depends, as we know, largely upon how frequently the word is encountered; hence, the student is helped not a little by the circumstance that a large majority of specific names are the very words from which the descrip- tive terms in common use have been derived. Further- more, these descriptive terms, as well as the names of the parts of plants and of genera and other groups, are in large part made up of a comparatively small number of Latin and Greek words, which once learned serve as helpful aids to the memory, and, indeed, often enable the student to tell at sight the meaning of a new botanical word. In our study of systematic botany we shall learn the more important descriptive terms as we need them in de- veloping a general idea of the natural classification of plants. The student will learn how to distinguish some of the more important families and higher groups, so that when he ex- amines a plant he can tell at least the sub-kingdom to which it belongs, usually also the class, sometimes the order, often the family, and in certain cases even the genus and species. At first we shall confine our study to those plants which produce flowers and seeds, leaving for later consideration the groups including ferns, mosses, lichens, mushrooms, and sea- vveeds. CHAPTER VIII THE PARTS OF A SEED-PLANT 91. Flax as a type. De CandoUe, one of the most learned of French botanists, was wont to say that he could teach all he knew of botany from a handful of plants. What he had in mind was doubtless the great truth that among the resemblances of plants to one another there are some of such fundamental importance that it becomes possible to discern amid the endless variety of forms a few plans of structure upon which all plants are built. His handful of specimens would have been so chosen that each might exhibit esjiecially well the features common to many kinds, and thus serve at once as a convenient standard of comparison and as a means of teaching truths of very wide application. A form which in this way is representative or typical of any group, natural- ists call a type. Flax (Figs. 217 I, H) will serve well as our type of phen- ogams or seed-plants because it possesses all the parts which they commonly show, and exhibits them in comparatively unmodified condition. Like all true flowering plants it pro- duces seeds. 92. The seed may be compared roughly to an egg. Much as in a hen's egg, for example, we have the shell covering a mass of food material provided for the chick or germ which lies within it, so in the seed (Fig. 279A) we find a protective seed-coat (c) enclosing seed-food (f) and a germ or embryo ^ (e). Much of the food provided for the flax embryo is already stored within the little plant itself; what remains to be ab- sorbed has been likened to the white of egg and is called the albumen ^ of the seed. The embryo within the seed is found ' Em'bry-o < Gr. embryon, germ. ^ Al-bu'mcn < L. alhus, white. 316 THE PARTS OF A SEED-PLANT 317 upon careful examination to be already a miniature plant, for it has a stem (s) bearing at its lower end the beginning of a root (r) which becomes apparent when the seed sprouts; while at the upper end of the stem are borne a pair of fleshy leaves (1) which after sprouting turn green, and between them a tiny bud (b) which is destined to grow into the stem, leaves, flowers, and fruit of the mature "j^lant. Each of these parts of the embryo has been given a special name. The little stem which bears all the other parts is the caidicle.^ Each of the first leaves is a cotyledon.- The bud at the top of the caulicle is known as the phwnde,^ while the rudimen- tary root at the lower end is called the radicle.'^ 93. The seedling and its development. When the seed germinates, the radicle is the first part to appear (Fig. 279B). Soon it grows into a root (Fig. 279C) covered with hairs through which absorption of soil-water takes place. Mean- while the cotyledons have been feeding upon the albumen to get material for their growth and for the elongation of the caulicle and root; and when finally this reserve food is ex- hausted, the empty seed-coat is cast off, the cotyledons become green and expand in the sunlight (Fig. 279D), and the plumule develops into a leafy shoot (Fig. 279 E). As. the root pene- trates doAvnwards into the soil it sends forth branches in various directions (Fig. 2171). At the same time the leafy shoot grows upward developing stem and leaves by the con- tinual unfolding of a bud at its tip which began as the plumule (Fig. 279 F). The place at which a leaf joins the stem is called a node,^ and the length of stem between two nodes, an internode.^ ^ Caul'i-cle ■< L. caidicidus, diminutive of caulis, slalk < Gr. kaulos, stalk. - Cot-5'-le'don < Gr. kotyle, a shallow cup, which some cotjdedons are supposed to resemble. ^ Plum'ule< L. plumula, a little plume, which the plumule of certain plants, such as the peanut or almond, somewhat resemble. ■* Rad'i-cle < L. radiculus, diminutive of radix, a root. The term radicle is sometimes used so as to include the caulicle, and caulicle is sometimes made to include the radicle as above defined; but the terms are coming to be understood in the sense here adopted. ^ Node < L. nodus, a knot, the joint being likened to a knot in a cord. ^ In-'ter-node < L. inter, between. 318 THE PARTS OF A SEED-PLANT Fici. 279. ^,:,.—F\ax Germination. A, seed, cut vertically to show the seed- coat (c), seed-food (f). embryo (e), with its seed-leaves (1), seed-bud (b), seed-stem (s) and seed-root (r). B, seed begmnmg to sprout; the seed- PHYSIOLOGICAL DIVISION OF LABOR 319 After a while new buds appear on the sides of the stem at points just above the nodes (P'i.a;. 280), that is to say, in the axil ^ or upper angle between leaf and stem; and these buds as the}' expand become lateral branches, which in turn may branch similarly. Finally, some of these buds, instead of producing more foliage, develop flowers (Fig. 2171). 94. The flower and the fruit. In the center of the flower (Fig. 21 711) we find a pidil - containing ovules ^ within an ovary * from the top of which grow five styles ^ each terminat- ing in a stigma.^ Around the pistil are five stamens,'' each producing pollen » within an anther ^ borne on a slender filnmeyit.^" Enveloping the stamens are five petals i' and five sepalsJ- Pollen falling upon the stigmas, brings about the development of the ovules into seeds while the ovary ripens into a fruit. Pistils and stamens thus being essential to the production of seed are called the essential organs of the flower, while the petals and sepals, more or less enveloping them, are called the ,^oraZ envelops or perianth. ^^ 95. Physiological division of labor. Even such a cursory examination as we have made of our typical plant is sufficient ' Ax'-il < L. axilla, arm-pit. ■ - Pis'-til < L. pisiillum, a pestle, such as apothecaries use for pound- ing drugs in a mortar, pistils often resembhng pestles more or less in form. ^ O'-vule < L. ovuhan, diminutive of ovum, an egg. ■• Ov'-ar-y < L. ova, plural of ovum; ary, repository. '" Style < Gr. stylos, a pillar. " Stig'ma < Gr. stigma, a spot. " Sta'men < Gr. stamon, a thread. * Pol'len < L. pollen, fine dust. ^ An'ther < Gr. anthein, to blossom. '"> Fil'a-ment < L. filum, thread. " Pet'al < Gr. petalos, outspread. 1- Sep'al < L. separ, separate, different. " Per'i-anth < Gr. peri, around; anthos, flower. stem (caulicle) has just pushed through the seed-coat and is pushing the seed-root (radicle) into the ground. C, later stage in which the radicle has elongated and produced root-hairs, while the caulicle has pushed up the seed. D, still later stage in which the caulicle has become further elongated and arched and the seed-leaves or cotyledons are growing out of the seed. E, plantlet showing pair of cotyledons ex- panded and ready to act like leaves; also three pairs of primary leaves and a stem developed from the seed-bud or plumule. F, plantlet still older, showing, in addition, secondary leaves, formed one at a joint. (Original.) 320 THE PARTS OF A SEED-PLANT to show not a little \-aricty and complexit}^ in the different parts which compose it, and one is aware that much more complexity of structure would appear upon further stud3\ But why the plant should have such a complex structure may not be at first so obvious. We are helped to an under- standing of the matter, however, by remembering that wherever there is much variety of work to be performed, it is an advantage to have the labor divided among different sets of workers, each fitted for their special share and cooperat- FiG. 280. — Flax Bud cut vertically and much enlarged to show the develop- ment of the leaves from protrusions arising at the side of the dome- like stem-tip which consists of formative material. (Original.) ing with the rest. This principle is shown clearly in the com- munity to which we belong, where the labor of meeting the needs of the peojile as a whole is divided among farmers, miners, manufacturers, merchants, soldiers, teachers, and many other classes, while in each class the work is divided and subdivided again and again. The degree of specialization and cooperation found in such advanced communities as our own chiefly distinguishes them, as we know, from such less advanced communities as the Indian tribes which preceded us upon the American continent; and w^e say that this was ORGANS AND THEIR FUNCTIONS 321 largely because their conditions of life were simpler and so their needs less than ours. Similarly we should find the higher plants, such as flax, contrasted most significantly with such lower forms as Irish moss in the extent to which they exhibit a differentiation of parts and mutual helpfulness throughout; and we should find a similar reason to hold good. Accordingly, we may not inaptly compare the roots, the stem and its branches, the leaves, and the parts of the flowers and fruit of our plant to the various classes of workers which we find in a civilized community, since the work of the whole is similarly divided among the parts and all labor for the common good. It is such an idea as this that naturalists have in mind when they speak of the physiological division of labor observable in a plant or an animal. 96. Organs and their functions. In either a plant or an animal any part having a special office to perform is called an organ,^ the special office being known as its function.- Thus the root of o.ur flax-plant is an organ the chief function of which is to absorb mineral substances from the soil. The function of the stem is mainly to support its leaves, flowers, and fruit advantageously; while the general function of its floral organs is to insure the production of good seed; and the function of its fruit is to bring about their dispersal. We often find the same function performed by different organs which are curiously unlike in other respects, as for example the function of support as performed by the tendrils of the pea (Fig. 37), the cfimbing roots of the poison-ivy (Fig. 210), and the grappling prickles of the rattan (Figs. 2231, II). Organs which agree in function are said to be ana- logues ^ of one another, or to be analogous. According to their main functions the parts of our typical plant may be classified conveniently as organs of nutrition {e. g., the root, foliage, leaves, and cotyledons); of support (the stem and its branches) ; of protection (the bark) ; of reproduction (the 1 Or'gan < Gr. organon, an instrument or tool. Since animals and plants arc made up of organs they are called organisms, and the mate- rials which are present in them alone are called organic, to distinguish them from inorganic or mineral substances. 2 Func'tion < L. funclio, performance. ^ An'-a-logue < Gr. ana, according to, logos, relation. 322 THE PARTS OF A SEED-PLANT flower); and of dissemination (the fruit). The first three of these groups, since they have to do primarily with the individual life of the plant, form what is called the vegetative system, while the others being concerned only with propaga- tion and the care of offspring constitute the reproductive system. 97. Morphological differentiation. From what has been said of the life history of flax it is plain that the differentiation of its parts progresses as the plant grows older. We saw that the parts of the embryo within the seed are all much alike, as are also the young foliage leaves and floral organs within the bud; but as the plant matures and its needs become more varied the parts come to have different functions to perform and take on the various forms which fit them for their special kinds of work. Thus, the mature flax differs from the same plant in its infancy much as do the higher plants from the lower. But in spite of the progressive cUffer- entiation shown by a growing plant we feel that even its more highly specialized organs correspond somehow in a fundamental way with certain of the earlier or less specialized ones. Petals, for example, although widely different from cotyledons in function, are yet in some ways so much like them and like ordinary foliage leaves that cotyledons are often called ''seed-leaves" while petals are familiarly known as "leaves of the flower." So, too, in comparing the parts of different plants we often find a fundamental likeness along with marked differences in function. Thus, the climbing roots of the ivy before mentioned are essentially the same in important particulars as the absorbing roots of flax. Not only among plants but also among animals it is true that analogous organs may show important differences, and similarly that organs which are not analogous may be essen- tially alike as holding corresponding places in the funda- mental plan of structure. A man's arm viewed as an organ for grasping is plainly the analogue of an elephant's trunk, and an opossum's tail; while viewed as a member of the bod}^ it corresponds to the fore leg of a horse, the flipper of a whale, and the wing of an eagle. Considerations of this MEMBERS OF THE PLANT BODY 323 nature lead us to inquire; What is the fundamental plan of structure exhibited bj^ our typical plant? and What may we rightly regard as the members of such a plant-body? 98. Morphological units. We have seen that the embryo flax is a miniature plant already possessing a stem-part, rudimentary leaves, and the beginning of a root. These parts we recognize as representing the main divisions of the plant, at least before it flowers, for we know that for many weeks as the plantlct grows it simply produces more root, more stem, and more leaves. If we examine minutely one of the leaf-buds (Fig. 280) we find it to contain a series of young leaves w^iich are smaller and smaller as we approach the tip of the stem until finally they appear as mere lobes. Thus we see that a leafy shoot begins as a tiny dome- shaped mass of growing material, which as it elongates, be- comes differentiated into (1) lateral lobes, which grow into leaves, and (2) a central or axial part constituting the stem which bears them. Soon in the axils of the young leaves appear growing points like the cone at the tip, and each of these becomes a bud which may develop into a leafy branch. Since corresponding parts arise at regular intervals, the whole shoot, especially as it grows older, takes the form of a series of segments or equivalent divisions each consisting of a leaf-part borne by a stem-section from which a bud or rudimentary branch may also develop. The embryo, we remember, had just these parts, and in addition bore a root. Often, such a shoot-segment cut from a plant and placed under favorable conditions for growth will send out a root, and develop other segments much as an embryo does; and, commonly, a cutting which consists of a single leaf attached to a bit of stem, is the least part of a flowering plant that can be made to grow independently. Hence such a seg- ment consisting of an internode and its node, together with the leaf or leaves it bears, has been regarded as constituting, in a way, a unit of plant structure. 99. Members of the plant body. A plant like flax is some- times thought of as a colony of segments or in other words as a community of closely connected individuals each con- sisting of a stem-part and leaf-part, and capable of producing 324 THE PARTS OF A SEED-PLANT a root, and so leading an independent existence. On this view each segment would correspond to an individual animal and its leaf-part and stem-part would be likened to the members of the animal body, such as the trunk and the liml)s. With- out accepting this extreme view of what constitutes an individual plant — a view not in accord with what we have learned about the development of the shoot — it may still be convenient to regard the bodies of the higher plants as built up of segments, much as zoologists regard the bodies of many segmented animals like earth-worms and lobsters as consisting of a series of roughly comparable units; and, similarly, just as the limb of an animal viewed as one of the main divisions of the body or of a segment is called a member, so the main divisions of a plant-segment — the stem, the leaf, and the root — viewed not as organs but merely as parts differing in origin and position, may be conveniently dis- tinguished as members of the plant body. But the question at once arises, supposing it to be admitted that the vegetating plant may be roughly likened to a many- storied building, each story being a segment, and the whole supported on a root foundation, can we yet find correspond- ing units of structure in the flower? If the flower is com- posed of segments it is evident that the different members must be more or less disguised. As regards the floral envel- opes we have already seen that their leaf-like nature is so thinly disguised that they are commonly recognized as "leaves of the flower." Indeed, we have only to suppose the internodes of the stem-parts to have remained as short as they were in the bud, while the leaf-parts expanded, to see that so far as origin and relative position are concerned, the floral envelopes are essentially^ like a leaf-rosette. But the stamens and the pistil present greater difficulties. Still, when we come to compare other flowers with those of the flax, we shall find much evidence going to show that even stamens and pistils correspond in large part to leaves. One sort of evidence — not indeed conclusive, but yet significant — is the occurrence now and then of monstrous flowers in which actual green leaves occupy the place of the stamens and pistil, much as if the organs had determined to throw off all dis- MEMBERS OF THE PLANT BODY 325 guise and exhilnt their true nature' The proof of a theory' is in the using; for the present it will be enough for us to have gotten a prehminary idea of what the segment theory means Avhen appUed to our typical plant. Other questions, closely connected with the foregoing one, are, What members ma}^ a segment have? and, How may these be distinguished under all their disguises? The flax embryo, as we have seen, represents a segment reduced to about its simplest terms. We here recognize an axial member bearing lateral members, — the stem-part and the leaf -part, — one impl^'ing the other. When the root-part appears we have another member which is also axial, but differs from the stem in being without leaves. As the root elongates there appear near its tip numerous hair-like projections which differ essentially from leaves in being merely superficial outgrowths not continuous with the innermost parts as is the case with leaves. Superficial appendages of this sort often occur in other plants on the stem and leaves as well as on the root. Such more or less hair-like outgrowths are best regarded as parts of members rather than as members. In the essential organs of the flower we meet with a difficulty regarding the real nature of the pollen-sacs and ovules or egg-sacs as we may call them. In the flax they both might be taken to be parts of the peculiar leaves which we regard as forming the stamens and pistil. But there are other plants, as we shall see, in which an ovule appears on the very tip of the stem or axis, while in some cases pollen-sacs seem to grow directly from the stem. We can then hardly call such organs parts of a leaf. On this account and for other reasons 1 The theory of floral structure which Hkens a flower to a leaf-rosette originated with the poet Goethe to whom it was suggested by seeing a green rose such as occasionally appears in gardens. This theory has proved to be a helpful means of understanding the relation of the various parts of plants to the fundamental plan of structure; but as it tells only part of the truth it has been somewhat misleading, and it requires to be modified considerably from its original form to be in accord with more recent views of vegetable morphology. As developed above, however, it is believed that the theory will be found to avoid the un- warranted assumptions which have brought into it discredit, and to re- tain the features which have made it useful, wliile at the same time such modifications are made as will render it a valuable means of con- veying modern views. 32G THE PARTS OF A SEED-PLANT which will appear later, we are led to regard both pollen-sacs and egg-sacs as distinct members of the plant body. We thus come to the conclusion that our t3'pical plant viewed morphologically is made up of members of the nature of stem, leaf, root, pollen-sac, and egg-sac; and that the whole body may be furthermore regarded as consisting of a chain of segments, each segment having at least a stem-part and a leaf-part and sometimes also other members. A root-member may be defined in a general way as typically a descending axis; a stem-meynber as an ascending leafy axis; and a leaf-member as a lateral, transversely flattened out- growth from a stem. Since stems and leaves imply one an- other, it is convenient to speak of them together as forming a shoot. Thus in our flax embryo the caulicle, cot^dedons, and plumule constitute the shoot as distinguished from the root-part. A sac-7nember, such as a pollen-sac or an egg'-sac, is really, as we shall see later, a spore-case essentially like that of Lycopodium (Fig. 166,i). Pollen grains are spores; and each egg-sac contains one or more comparative!}' large spores within which an embryo arises. Thus a sac-member is known by what it produces. As to how these different members may be further distinguished we shall learn more fully when we come to compare other plants with our type. 100. Homologies. We have already seen that the terms analog}^, analogue, and analogous, afford us a means of ex- pressing physiological equivalence or similarity in function. To express morphological correspondence or similarity in origin and position naturalists use the companion terms homology,^ homologue, homologous. Members of the same sort are said to be homologues of one another; any form of leaf-member, for instance, being homologous with any other form. Cotyledons and petals are homologues, because both are leaf-members, and they would accordingly be spoken of as homologous parts, homologous organs, or homologous members. The principal parts of our typical plant and their homologies as here understood are indicated in the accom- panying diagram (Fig. 281). The tracing of homologies forms the basis of morphology, 1 Ho-mol'o-gy < Gr. homoa, same. HOMOLOGIES 327 just as the morphological study of plants forms the scientific basis of systematic botam^ To a certain extent the concep- tions involved are necessarily abstract, or, so to say, dia- grammatic; for the parts of plants are thus viewed only in one aspect, and for the sake of being able to think of them Fig. 281. — Diagram of a typical fioweriiig piaut showing the principal parts and their homologies. Root-members are black; stem-members, shaded with lines running lengthwise; leaf-members, shaded with lines across; and sac-members, unshaded. (Original.) simply many facts are deliberately left out of account. The conclusions reached nevertheless may be true so far as they go, and are valuable aids to fuller knowledge; but the student should remember that natural objects are never diagram- matic and that Nature does not draw the sharp lines of dis- tinction which we may find it useful to assume. CHAPTER IX THE CROWFOOT FAMILY 101. General features. In several respects the crowfoot family is the best one with which to begin our study of plant groups. It forms an especially serviceable standard of com- parison because its members, as Ave shall see, are remarkably simple in their plan of structure — at least for seed-plants — and at the same time the various species display a wide range of variety in detail. Moreover, it was his careful study of this family w^hich led the younger Jussieu to an understanding of those fundamental principles of classification which he applied so brilliantly in founding the natural system. To us it will present problems which once solved will simplify and illuminate all our future study. Of the plants already examinetl the following, as we have seen, are of this family: marsh-marigold (Caltha palustris, page 198), tall buttercup (Ranunculus acris, page 216), cUtch crowfoot (R. sceleratus, page 216), wind-flower (Ane- mone nemerosa, page 205), and monkshood (Aconitum Napellus, page 191). The family is made up of about 700 species in about 30 genera. From the few examples above given and a study of those shown in Figs. 282-297, we may gain, however, a fair idea of the range of peculiarities exhib- ited by the family as a whole. At first sight it may seem scarcely possible to find among plants which differ so much one from another any peculiarity or set of peculiarities common to all and yet not possessed by other seed-plants. Examination will show us, however, that as a group they may be distinguished at least by the lack of complicating features which other families show, and we shall find further- more a few positive peculiarities which are more or less characteristic. 328 THE CROWFOOT FAMILY 329 I I 1 ^at^y^^^/iK*"^^ Pi^ 98'> -Peonv {Pc^onia officinalis, Crowfoot Family I^^'^^^'^'^^f^'^f; 1 flowering branch. B, flower, cut vertically C, stamen. A floral :?inoTnni E flower with stamens and petals removed. F, truit. « feed entire aiTd cut vertically. (LcMaout and Decaisne.)-Peren- Sal herb gro^^ns 1 m. tall; leaves dark green above; flowers crimson, fruit hairy. Native home, Europe. 330 THE CROWFOOT FAMILY 102. The vegetative organs compared. Let us begin by comparing the marsh-marigold as a type of the family with the other representatives here illustrated. This plant we Fig. 283. — Christmas Rose and Mouse-tail (Hcllcborus niger and Myosurus minimus. Crowfoot Family, Raiiunculacece). 1, Flowering plant of Christmas rose, J. 2, flowering plant of mouse-tail, §, with flower, en- larged, above. (Kerner.) — -The Christmas rose is a perennial herb, about 30 cm. tall; leaves evergreen, glossy; flowers white or pinkish; fruit dry. Native home, Europe. The mouse-tail is an annual with greenish flowers and dry fruit. Native to Eurasia, Northern Africa, Australia, and North America. know to be an herb (see page 198) because the i)arts above ground are too tender and succulent to live through the winter. The roots do persist however, and serve as store- houses for food which the plant uses in the following spring. TH]<: VKCKTATIVE ORGANS TOMFAHl':!) :«1 Thus it is enabled to live from year to year, or, in a word, is a perennial. Whenever we find an herb retaining the remains of more or less withered leaves and stems, or of shrunken roots Fig. 284. — Christmas Rose. A, flower, entire. B, same, cut vertically. C, floral diagram. D, staminode. E, pistil. (LeMaout and Deeaisne.) Fig. 285 I. — Mouse-tail. Flower, entire. Same, cut vertically. (Baillon.) evidently belonging to a previous year, and at the same time having organs, underground or near the surface, swollen with food evidently destined to supply material for the 332 THE CROWFOOT FAMILY growth of buds fitted to live over the \vint(n- we may safel>' conclude that we have a perennial plant. If, on the con- FiG. 285, II. — Mouse-tail. Pistil, entire. Same, cut vertically. Staminode. (Baillon.) Fio. 286. — Feiiiiel-flowers (Nigella sativa and *V. damasccna, Crowfoot Family, Ranunculaceee) . A, flowering top of N. sativa. B, flower, cut vertically. C, stamen. Z>, staminode. E, fruit. F, pistil. G, seed, entire, and cut vertically. H , floral diagram. J, fruit of .V. damascena, cut across. (LeMaout and Dccaisne.) — Annuals with bluish or white flowers and dry fruit. Natives of the Old World. trary, a full grown herb lacks all such signs of a previous year's growth or of provision for the future, it is clearly an THE VEC;ETATIVE organs compared 333 annual; while if there are signs (such as a swollen root or leaf-rosette) implying only a past year's growth with no provision beyond, the plant would be called a biennial, i. e., one completing its life in two years. Fig. 287, I. — Columbine (Aquilcgia vulgaris, Crowfoot Family, Ranun- culacecv). Flowering top. Flower, entire and cut vertically. Pistil surrounded by rudimentary stamens. (Baillon.) — Perennial herb 45-60 cm. tali; leaves finely hairy; flowers purple, violet, white, etc.; fruit dry. Eurasia. Common in gardens. Nearly all the members of this family are perennial herbs. A few, such as the mouse-tail, are annuals; and there are some more or less woody forms, as for example, certain species of Clematis which are woody and climbing. None of the family are trees. ^ 1 The following signs are often used for brevity in botanical descrip- tions: © for an annual, @ for a biennial, and % for a perennial herb; ^ for a vine whether trailing, chmbing, or twining; b for a woody plant; i for a small shrub, 3 for a large one; _5 for a shrubby tree and_5 for one of considerable size. To these we may add O to mean herbaceous as a counterpart to the sign for woody. 334 THE CROWFOOT FAMILY The stem parts of the marsh-marigold agree fundamentally Avith those of the flax plant in their general form aiid mode of branching, although differing in such minor details as slender- ness and toughness. There is, however, a more significant Fig. 2.S7, II. — Columbine. Floral diagram. Stamens. Ovary, cut across. Fruit. Seed, entire, enlarged. Same, cut vertically. (Baillon.) Fig. 28S, I. — Baneberry (Aciaa spicata, Crowfoot Family, RanunculacecF). Flowering top. (LeMaout and Decaisne.) — Perennial herb 30-60 cm. tall; flowers white or bluish; fruit fleshy, purplish or red. Native home, Eurasia, Northern .States. difference in the length of the lower internodes, which in the marsh-marigold and man}- other members of the family are so short that the foliage leaves are crowded together into a rosette. Somewhat similarly abbreviated internodes bearing scale-like leaf-members often remain underground, as in THE CROWFOOT FAMILY 335 .--y^VZ M^isJ D Fig. 288, II. — Baneberry. A, flower, cut vertically. B, floral diagram. C, stamen. D, pistil, enlarged. E, fruit. F, seed, entire and cut vertically. (LeMaout and Decaisnc.) Fig. 289. — Mountain Clematis (Clematis alpina, Crowfoot Family, Rnnun- culacece). Part of plant climbing by means of its leaf-stalks used as tendrils. (Kerner.) — A somewhat woody climber with stems nearly 2 m. long, bright blue flowers and hairy-taUed fruits. Native home Eurasia and Northwestern North America; cultivated. 336 THE CROWFOOT FAMILY the wood-anomony and the Christmas rose, and persist over the winter as a res(>rv()ir of food upon which buds may feed the following spring. Such an elongated subterranean stem is called a rootstock or rhizome.'- When, as in the bulbous crowfoot, the subterranean base of the stem becomes so much gorged with food as to be spha?roidal or oblate in form it is termed a ''solid bulb" or corm.' Fig. 290. — Vine-bower Clematis {Clematis Vilalba, Crowfoot Family, RanunculaceoB) . A, flower-cluster. B, flower. C, same, cut vertically. D, stamen. E, pistils. F, floral diagram. G, fruit. H, base of fruit, cut vertically. (LeMaout and Dccaisnc.) — A somewhat woody climber growing; 10 m. long; flowers dull white; fruit hoary. Native home, Mediterranean Region; cultivated in gardens. Turning now to the foliage of our marsh-marigold we find the leaves to be of a form very common among seed-plants, and comparatively simple although more highly developed than the leaves of flax. In a marsh-marigold leaf we may distinguish a broadly expanded part, the blade, borne on a footstalk or petiole; » which expands again at its base into a ' Rhiz-ome < Gr. rhiza, root, because of its root-like appearance. ^ Corm < Or. kormon, a pollarded tree-trunk. ' Pet'-i-ole < L. pciiolm^, a little foot, diminutive of pes, pedis, a foot. THE VEGETATIVE ORGANS COMPARED 337 sort of sheath. The framework of the leaf when it reaches the blade divides into a number of main branches, or ribs. These radiate from the top of the petiole and maj'^ divide again into secondary branches, or vei7is, which finally are connected so as to form an irregular net-work by minute branches called reinlets. When a leaf has ribs radiating thus, like the bones in the palm of one's hand, it is said to be pal- mately ribbed, and when the veinlets form an irregular net- FiG. 291. — Erect Silky Clematis {Clematis ochroleuca. Crowfoot Family, Ranimculacece) . Flowering branches. Fruit. (Britton and Brown.) — Perennial herb, somewhat woody, 30-60 cm. tall; leaves silky-hairy beneath; flowers yellowLsh; fruit yellowish brown. Native home, Eastern United States. work, it is netted-veined . The ribs and veins are also called nerves and their arrangement the nervation of a leaf, the ar- rangement of the veinlets being called the venation. On comparing with the leaves of the marsh-marigold those of the ditch crowfoot we find the same general plan of struc- ture l5ut with the difference that the leaf base is narrower, and the l)lade is divided into branches corresponding to the ribs. The branches of the upper leaves are so narrow as to 838 THL] CROWFOOT FAMILY suggest a rosemlilanco to the toes of a l)ir(l, which lias given rise to the name " crowfoot .'" In the tall crowfoot the liranch- Fui. 2'J2. — Pasque-flower (Atietnone Pulsatilla, Crowfoot Family, Ramincu- lacew). Plant in flower and fniit. (Baillon.) — -Perennial herb about 20-30 cm. tall; leaves hairy; flowers blue or purplish; fruit hoary. Native home, Europe; cultivated in gardens. ing of th(^ blade is carried still further and follows the veins. A similar branching is shown in the leaves of monkshood and many other menil)ers of the family. THE VEGETATIVE ORGANS COMPARED 330 All the leaves so far considered agree in having the blade of a single piece however much it may be branched or sub- divided. That is to say, the green pulp of the ])lade, al- though it may l)e but little developed between the ribs, is still continuous. Such are called simple leaves. When the green pulp is discontinuous between the ribs, as in the leaves of the Christmas rose, the blade becomes divided into second- ary blades or leaflets, each of which may be borne on a little B Do «' 'S's-u, ! Fig. 293. — Meadow Rue {Thulictrum flavum, Crowfoot Family, Raniincu' lacece). A, flower-cluster. B, flower, enlarged. C, same, cut vertically. D, floral diagram. E, pistils. F, fruit, entire, and cut vertically. G, seed. (LeMaout and Decaisne.) — -Perennial herb about 1 m. tall; flowers yellow; fruit dry. Native home, Eurasia. stalk of its own, called a petiolule^ Such leaves are classed as divided or compound. If, as in this example, the leaflets or their petiolules spring directly from the main petiole the leaf is distinguished as once-compound; when, as in baneberries, the branching of the blade is carried a stage farther and the leaflets or their petiolules arise from branches of the petiole, the leaf becomes twice-compound; or the subdivision may be carried still farther, as in columbines. A leaf more than once compounded is termed decompound. Since in ^ Pet'-i-o-lule < L. petiolulua, diminutive of petiolu>i, petiole. 340 THE CROWFOOT FAMILY all these cases the branching of the blade follows the palmate plan the leaves are conveniently described as palmately divided, or palmately once-, twice-, or decompound. The leaves of the Christmas rose and some other members of the family are peculiar in having the lateral divisions not quite sepa- rated, thus making them in a way intermediate between Fig. 294. — Bracts and petals of peony connected by intermediate forms. Parts marked G are green; Y, yellow; and R, red. (Original.) Fig. 295. — Stamens and staminodes of peony showing intermediate forms. Parts marked R are red; and. those marked Y are yellow. (Original.) simple and compound palmate leaves. Such leaves are dis- tinguished as pedate.^ The palmate type of leaf prevails throughout the crowfoot family, the only departures from the rule being a few such cases as the narrow leaves of mouse-tail in which the frame- work is unbranched or obscure, and a few cases in which a midrib or continuation of the petiole gives off lateral branches as in the leaves of the pasque-flower and clematis ' Ped' ate. onia; the valvate, by an inverted comma opposed to an apostrophe, as in Clematis. For each floral organ the number or numerical sign following a letter tells how many of the parts represented are present. The plus sign, +, means "or more," so that 5+ would be read "five or more." The "plus or minus" sign, =fc, is to be read "more or less." The algebraic symbol of infinity, 00, stands here for "many" or "an indefinite number." As a companion sign, oc may be used to mean few. When the absence of an organ needs to he noted a zero, 0, is used. A dash between numerical signs means "to"; thus, 3-5 would be read ' ' three to five " ; 0- 0° " none to many. ' ' Simply a dash after a numerical sign means "or less"; thus 5- would be read "five or less." When the numerical signs are in such fractional form as I or i (Aconitum formula) it shows that the flower is irregular so far as the organs so represented are concerned; otherwise, the flower is understood to be regular. If the numerator be an odd number it indicates that a single member of the set, more or less unlike the others, is uppermost, as for example, the hooded sepal of Aconitum : an even number, instead, shows that a pair of similar parts is uppermost, as is the case with the staminodes in the same flower. Unless otherwise indicated the floral organs are understood to be free and distinct. Partial coalescence of parts, as in the carpels of Nigella, is indicated by placing after their numerical sign a small parenthesis: thus, for the example cited CE 5 ±) would be read "carpels five, more or less, partially coalescent below." There being no indication to the contrary it is also to be under- stood that the floral organs regularly alternate, and that the anthers THE FAMILY CHAIN 355 dehisce by longitudinal slits. The expression T ^ means that the torus is convex and implies that the perianth and androecium are hypogynous. When as in Pa>onia they are perigynous this is indi- cated by T w which represents the torus as concave. The form of the ovules is shown b}^ a mark jilaced over their numerical sign, a circumflex accent-mark meaning that the ovule is anatropous. Their ventral position is understood in simple pistils, while in compound pistils like that of Nigella, the single parenthesis after the number of carpels implies that the ovules are on an axile placenta. When the pericarp becomes fleshy as in Actcea this is indicated by an exclamation mark after the C. When the pericarp is dry, as in Caltha, there is instead an inverted exclamation mark. Inde- hiscence is indicated by the sign < . When the pericarp dehisces along a ventral suture as in Caltha, etc., the sign < is employed. In all the formulas the expression G-N implies that the embryo is uncoiled within albumen. The scheme of plant formulas which is here proposed and which will be further elaborated in the following pages, is an extension and modification of the floral formulas used by many botanists. As a sort of botanical shorthand of wide application it is l^elieved that the student will find it not only labor-saving but helpful in grasping plant relationships. After a little use, what seemed strange will have become familiar and a glance will discover important characters that might easily escape notice in comparing equallj' full verbal descriptions. 105. The family chain. Having learned the signification of these symbols we are now in position to use the formulas as a ready means of comparing the main structural features of our representa- tive genera to see how they are linked together. Take, for instance, Caltha and Pseonia. If we conceive of a marsh-marigold having a concave torus, a perianth differentiated into calyx and corolla, and pinnately compound leaves, such a plant would be classed as a peony. By these same features, however, it might be distinguished from all the otheY genera. Therefore, although closely linked with Caltha, Paeonia is placed on a line apart in the tabular view. Helleborus differs from Caltha chiefly in having the carpels some- times coalesced and in possessing staminodes. In these respects it is a link connecting Caltha with Nigella which has the carpels always coalescent, and differs from Helleborus only in having pinnate instead of palmate leaves, some of which may be so near the flower as to constitute an involucre, and in consisting of annual rather than perennial herbs. Aquilegia, with its carpels distinct, is more like Caltha, but differs from both Caltha and Nigella in having the carpels always five, staminodes in two inner sets of five and one outer set of the same number, and in having the leaves ternately decompound. 356 THE CROWFOOT FAMILY A monkshood is like a columbine except for irregularity of sepals and staminodes, absence of inner staminodes, indeterminate inflorescence, simplicity of leaves, and sometimes fewer carpels. All the alcove genera agree in having numerous ovules, all of which may become seeds, contained in several or many carpels which become dry and dehiscent in fruit. In Actsea the carpels are reduced to one, which becomes fleshy and indehiscent in fruit; the staminodes may be fewer, both they and the sepals are regular; and the leaves are ternately decompound: otherwise the genus resembles Aconitum. Passing now to Anemone we find its most striking differences from Caltha and the other genera already described to be the im- perfect development of several of the ovules in each carpel, the ripening of only one ovule, the indehiscence of the fruit, and the possession of an involucre of two or three bracts. In these respects it forms a link between our type genus and Clematis where the rudimentary ovules are commonly fewer, and all the leaves (like the bracts in some species of Anemone) are opposite. A still further divergence in Clematis appears in the occasional imperfection of the flowers, the valvate aestivation of the sepals, the ternate or pinnate nervation of the leaves, and the climbing habit and woody stem sometimes developed. In Ranunculus we find a still further reduction of the ovules; an invariable presence of both essential organs and staminodes; imbricate aestivation of the sepals: alternate, palmate, simple leaves; and sometimes annual duration: thus being in some respects more nearly like Caltha, while in others it is more divergent. Finally, an extreme of divergence by reduction or simplification is reached in the mouse-tails which may be regarded as annual crow- foots with only about five stamens, staminodes, and sepals, bractless, solitary flowers, and leaves with unbranched or obscure nervation. It may seem a long way from such plants to peonies; but, as we see, there are intermediate links binding them pretty closely together. As the student examines other members of the same famil}'- he will find that they may be readily interposed as links in the same chain with those already studied. Indeed, the transitions will appear less abrupt than between the few examples to which we have confined ourselves. His experience will be much like that of a botanist with forms newly discovered. He compares them with the forms already known and links them with those which they most nearly resemble. Thus link by link are family chains forged in botanical systems. As in the present case, the chain may branch, and it might be questioned whether it would not be better to regard the branches as separate families. That depends upon how close the linkage appears to be, and as to that the judgment of experts may differ. In any event the definition of any family properly follows the attempt at natural grouping, and may require revision with advancing knowledge or change of view. Such changes in THE FAMILY CHAIN 357 classification the history of the science illustrates; yet progress is in the direction of stal)ility, and certain chains,- having held from the first, bid fair to endure. The integrity of tlie Ranunculacea?, for example, seems assured in spite of the witle divergence of its extreme forms and in spite of the difficulty of defining its limits. We have now to define the family as best we can. The generic formulas will help us to a formula for the family and this in turn will lead us to our definition. Taking the prevailing characteristics of each part as typical for the family, and neglecting the less sig- nificant exceptions to the general rule, we may express a generalized view of the salient features as shown in the formula of Ranunculacese on pages 404, 405. The only invariable features here expressed are the anatropous ovule and the uncoiled embryo surrounded by albumen, and these as we shall see are common to a number of other families. But, as we shall also see in comparing the Ranunculacese with other groups, it lacks features which they possess. Taking into account all the facts we have learned, the crow^foot family may be described as consisting of herbaceous or rarely w^oody plants, never trees, without milky juice, oil or other secretions in special reservoirs, but with a mostl}' colorless and odorless sap which is generally acrid, and in some cases renders the plant poisonous to eat or to touch; leaves mostly palmately branched, or at least palmately ribbed; flowers mostly regular and perfect with the parts free and cUstinct (with rare exceptions) ; sepals commonly five, generally petaloid; petals rarely present, often replaced by more or less petaloid staminodal nectaries of widely differing forms; stamens generally numerous; anthers de- hiscing by slits; pistils almost always simple, numerous, few, or rarely solitary; ovules anatropous, many, few or solitary, sometimes rudimentary; fruit follicular, capsular, achenial, or rarely fleshy; the seeds with hard albumen sur- rounding a minute uncoiled embryo. Or, if we disregard all that is untj'pical, it may be said that whenever we find an herb with the juice colorless and scentless, the flowers having all their parts distinct and free, sepals about five, and essential organs numerous, we may be tolerably sure that our plant is one of the crowfoot family, although some departure from these characteristics would not necessarily exclude it from the group. CHAPTER X VARIOUS PLANT GROUPS 106. The magnolia family (Magnoliaceae) is a compara- tively small group well representetl by magnolias (Alag- nolia, page 262), the tulip-tree (Liriodendron, page 261), and star-anise (lUicium, page 143). At first sight there might seem to be small resemblance between these and crowfoot- like plants; but let us see upon what points of difference we can exclude them from the crowfoot family. The seeds are essentially the same as those of the crowfoot family in having a small uncoiled embryo in copious albumen. The fruit of star-anise consists of follicles, much like those of the marsh-marigold, though with only one seed in each; while the carpels of the tulip-tree ripen into achenes differing from those of anemonies mainly in having wing-like out- growths. Such winged fruits are termed sayymi^as.^ The mag- nolia fruit consists of a cone-like aggregation of follicles differing from those of star-anise in dehiscing by a dorsal suture, and in producing one or two seeds which have a fleshy outer layer of bright color, and which dangle on slender threads when ripe. Neither the androecium nor the perianth present any new features. Nor do we find anything essen- tially different in regard to the inflorescence or the leaves except that in the tulip-tree and magnolia there are leaflet- like appendages at the base of the petiole. These stipules,^ as they are called, serve as organs of protection for the unex- panded leaves. In these plants they soon fall off, and so do not appear in the figures. Well-developed stipules are shown ' Sa-ma'ra < L. samara, the winged fruit of the elm. ' Stip'ule < L. stipula, stubble, diminutive of stipes, stalk, the stipules in their relation to the petiole being likened to the short stubble standing at the base of a stalk of grain. THE MAGNOLIA FAMILY 359 in figures 159,^ and 271. Somewhat similar expansions serv- ing for protection occur at the base of marsh-marigold leaves; but these, although suggesting stipules, are not regarded as sufficiently developed to deserve the name. The leaves of star-anise, as of the crowfoot famil}^ are exstipulate,^ that is, without stipules. Finally, as regards their habit, ^ or general ap- pearance, the tulip-tree is, as its name implies, a tree, while the species of magnolia and star-anise are either trees or shrubs. The result of our examination thus far is to show that star-anise in several particulars forms a good link connecting the tulip-tree with members of the crowfoot family, and we have not 3'et found a single feature which will serve to dis- tinguish all of the magnolia famil}' from all of the crowfoot family. This resemblance will appear still more plainly if we express in formulas the facts observable in our examples. Let us indicate the presence of stipules by an inverted dagger sign, \; a wing on the pericarp by an inverted interrogation mark, i ; and dorsal dehiscence by > . We may then write our formulas of IMagnolia, Illicium, and Liriodendron ^ as shown on pages 404, 405. If we added to these examples other magnoliaceous genera we should of course introduce some new variations of structure, but these would afford us no better family characters. A formula typical of the family would still be the same as that given below the three genera mentioned. Comparing our magnoliaceous formulas with the ranunculaceous ones we find that while prevailing features differ — so much so indeed as to make it desirable to group the plants in separate fam- ilies— the departures from the type in one family often match those of the other. There is, however, a general difference, not shown in the figures, which serves to separate the two groups. All mem- bers of the magnolia family have in the leaf-pulp, floral leaves, pith, and other soft parts, minute reservoirs of volatile oil, which are entirely lacking in the crowfoot famil3\ These little reservoirs may be seen readily with a hand lens by viewing ^ Ex-stip'u-late < L. ex, \\'ithout ; stipula, stipula - Hab'it < Iv. habitus, appearance. ' The plant formulas referred to in this and succeeding sections, together with the ranunculaceous formulas already given, are grouped on pages 404-427 to facilitate their being compared with one another. 360 VARIOUS PLANT GROUPS a leaf, petal, or slice of pith against the light, when they ap- pear as translucent, scattered clots. This oil it is which renders the flowers of the family fragrant, and gives its flavor to the fruit of star-anise. Scarcely a trace of such odors are to be found in the crowfoot family. We may therefore define the magnolia family as woody plants having fragrant, solitary, regular flowers, more or less like those of the crowfoot family, but with minute reservoirs of volatile oil in various parts. 107. The laurel family (Lauraceae) consists also of woody plants with oil reservoirs similar to those of the magnolia family. This aromatic oil gives to sassafras (Sassafras officinale, page 168) and to cinnamon and camphor (Cinna- momum, pages 135, 178), as we have seen, their chief economic value. Between these and our examples of the magnolia and crowfoot families may also be found many other similarities, either in habit, form of leaves, or floral structure. The morphology of the gj^noecium in the laurel family is somewhat doubtful. Apparently there is only a single carpel, much as in the baneberry, but in sassafras the three-lobed stigma may be evidence of three carpels which coalesce so completely as to form a one-celled, one-styled pistil. A further peculiarity of sassafras is that the flowers are all imperfect and that the two kinds are alwaj^s on distinct plants. The term dicedous ' is applied to this condition. A striking feature found throughout the family is the dehiscence of the anthers by upUfted valves. This is indicated in the formulas by FA^. Another general peculiarity is that the concave torus often becomes fleshy and cup-like in fruit — a condition indicated by T^T!. The sign ~ meaning "or otherwise" when there are noteworthy exceptions, is also introduced in the formulas of this family, and ? is used to indicate doubt. See pages 406, 407 for formulas of Sassafras and Cinnamomum and, derived from them (neglecting exceptions) a typical formula for the family. Woody plants with minute reservoirs of oil, and regular flowers more or less like those of the croufoot family hut having the perianth and androecium mostly perigynous and the anthers 1 Di-ce'ci-ous < Gr. c/ is, two; oilos, household; symbolized by cf : 9. THE POPPY FAMILY 361 always dehiscing by uplifted valves, constitute the chief mem- bers of the family. 108. The crowfoot order (Ranunculales or Ranales). A comparison of tlie three famihes we have been studying shows them to be closely linked together, much as are the genera within each family. By such linkage there is formed a natural chain of families including these and several others resembling them in important respects. Such a group of families is termed, as we have seen (page 8), an order. That which clusters about the crowfoot family takes significantly the name of the crowfoot order. The prevailing characters of Ranunculales are expressed in the formula of the order given on pages 406, 407. Neglecting the more variable or exceptional features we may say that the plants of this order, though differing widely in habit, foliage, and inflorescence, are characterized by having usually cymose inflorescences of mostly -perfect, regular, and hypogynous flowers with well-developed perianth often in whorls of three, stamens and, carpels usually numerous, and all parts commonly distinct and free. 109. The poppy family (Papaveraceae) is represented sufficiently well for our purpose by the opium poppy (Papaver somniferum, pages 182, 183). Like all the other species of its genus, it contains instead of volatile oil a milky juice from which, as we have seen, opium is obtained. Many other genera of the family contain a similar juice which in some cases is bright yellow, and in others red. Sometimes the juice is watery. The main structural features of Papaver appear in its formula on pages 406, 407. The only new features calling for special notice concern the gjTioecium which, unlike any in the crowfoot order (ex- cept possibly in the laurel family) , consists of several carpels so united as to form a compound pistil with a one-celled ovary. That is to say, the carpellary leaves as they grow have the right edge of one coalescent with the left edge of its neighbor. The united edges of neighboring carpels thus form placentije which lie along the outer wall of the compound 362 VARIOUS PLANT GROUPS ovary. Such placentte are termed parietal.^ The capsule in poppies opens pecuHarly by httle pores hke windows under the eaves of the overhanging stigma-ring. Such opening by pores, is called poricidal ^ dehiscence. With but slight modifications, not calling for special comment, the formula of Papaver becom.es typical of the family as shown on pages 406, 407. The family may generally be recognized as being mostly herbs, commonly having a milky or colored juice, and hypogy- 710US flowers with the floral envelopes most often in ichorls of two, the stamens usually numerous, the pistil always co?npoimd, one-celled and with parietal placentoe, and the seeds albuminous with the embryo sometimes curved but neither coiled nor bent. 110. The mustard family (Cruciferae) agrees closely with the poppy family in general form and floral structure, as may be seen by comparing our figures of cabbages, turnips, mustards, and rape (Brassica, pages 54, 66-70), watercress and horseradish (Nasturtium, pages 70, 71, 144), and radish (Raphanus, page 55). The main family differences are in the bracts and bractlets, the number of stamens, and peculiarities of the gyncecium. While the members of the poppy family have bracts and often bractlets of the usual sort (which therefore do not call for special notice), the members of the mustard family are almost unique in having no bracts within the inflorescence. Hence they are described as ebracteateJ In a flower of the mustard family there are two outer and shorter stamens, alternating with two inner pairs of longer ones. Botanists regard these inner pairs as representing each a single stamen branched or divided into two. The fact that a whorl is thus divided into sets is expressed in our formulas by the sign of division, H- , connecting the number in the whorl with the number of sets. The carpels of the mustard family are normally only two, ' Pa-ri'e-tal < L. parictalis, belonging to a wall < paries, a wall; indicated by the symbol () placed after the number of the carpels. - Por-i-ci'dal < L. poms, pore; ccedire, to cut; indicated by the sign° placed after that of the pericarp. ' F-brac'tc-atc < L. e, without; bradea, bract. Bo. THE ROSE FAMILY 363 as in certain of the poppy family, but the ovarj'^ instead of being one-celled is divided into two compartments by a partition extending between the parietal placentae. When ripe the carpels mostly separate from the placentae and from this partition. Such a fruit is called a silique.^ The ovules differ from any we have seen among the plants of the crow- foot order in lacking a raphe and being curved to a somewhat kidney-like form. When thus curved, ovules are described as campy lotropous.- The seeds are almost alwaj'S exalbuminous and have the embryo commonly bent in various waj's — a peculiaritj' expressed in the formulas by CrA- Note how closely similar are the formulas of Brassica, Nasturtium, Raphanus, and Cruciferte given on pages 406, 407. As a definition of the family we have thus: — Mustard family : mostly herbs without milky or colored juice or oil reservoirs, often of sharp taste though pleasant flavor; ebracteate inflorescence; usually hypogynous flowers ivith all the parts in ivhorls of two (with the apparent exception of the four inner and longer stamens), the ovary divided into two cells by a partition joining the parietal placentw; the fruit almost always a silique with exalbuminous seeds having the embryo variously bent. 111. The poppy order (Papaverales or Rhoeadales) com- prises a few families well represented by the poppy and the mustard families and agreeing in having mostly racemose inflorescences of complete, hypogynous, regular or irregidar flowers with the sepals, petals, and stamens all distinct and free, and a compound pistil with parietal placenta;. It is the union of the carpels by their edges which mainly dis- tinguishes this from the crowfoot order. For comparison we have a t}T)ical formula of the order on pages 408, 409. 112. The rose family (Rosaceae) as illustrated by the almond (Fig. 31, page 42), apple (Figs. 91 I, II, pages 86, 87), pear (Fig. 92, page 87), quince (Figs. 93 I, II, page 88), 1 Si-lique' < L. siliqua, a pod; C i - . - Cam-py-lot'ro-pous < Gr. kampijlos, curved; trope, a turn. E oo. 364 VARIOUS PLANT GROUPS peach (Fig. 94, page 89), plum (Fig. 95, page 90), cherry (Fig. 96, page 90), raspl)erry (Fig. 97, page 91), straw- berry (Figs. 98 I-III, page 92), and roses (Figs. 148 II, III, 298, pages 150, 151, 378), is seen to possess many features of floral structure resembling more nearly those of the crowfoot family than of any other family we have studied. Note in the formulas of Rosa, Fragaria, Rubus, Primus, Cydonia, and Pyrus, given on pages 408, 409, that the floral envelopes are mostly in fives, while the essential organs are commonly numerous, and that all are free and distinct, except sometimes the carpels, which then, unlike poppy carpels, have axile placentae. An miusual form of calyx is found in strawberries (Fra- garia). Here the sepals have stipules which coalesce in pairs so as to form what looks like a calyx upon a caljTc , and is termed 'therefore an epicalyx.^ The only other features not before encountered belong to the torus and the fruit. Throughout the family the torus is concave or cup-like, and it is mostly free as in peonies and our examples of the laurel family. In roses (Rosa) it completely envelopes the carpels, and be- comes fleshy and bright colored while the pericarps ripen into hard nutlets,^ the wdiole forming a so-called "hip." The strawberry fruit consists mainly of the upper part of the torus,^ much swollen and bearing numerous achenes. Rasp- berries have the upper part of the torus comparatively dry, and in fruit the pericarps finally separate from it. As these ripen, an outer layer becomes fleshy while an inner layer hardens like an olive stone. A fruit in which the pericarp is thus differentiated is called a "stone-fruit" or drupe.* In raspberries and thimbleberries the little drupes coalesce sufficiently to form a thimble-like mass after they separate from the torus. In blackberries, on the contrary, the little drupes remain attached to the part of the torus which bears ' E"pi-ca'lyx < L. epi, upon. S ]. 2 The hardening of the pericarp is expressed in the formulas by two inverted exclamation marks. ' A small t to represent part of the torus is used in the formulas instead of the large capital. * Drupe < L. drupa, a ripe olive. C//.' THE PULSE FAMILY 365 them, or in other words, the pericarps adhere i to the torus, as botanists say of the union of dissimilar parts. Such adhesion is represented in the Rubus formula by a bracket placed after the pericarp signs. The bracket is separated Idj^ a comma from the i)receding signs to show that in this genus the pericarps are sometimes free. Similarly the expression t;,!, means that the upper jiart of the torus may be either dry or fleshy in fruit, while Cjl! means that each pericarp is hard within and fleshy with- out, i. e., drupaceous. Each flower of plums, peaches, almonds, and cherries (Prunus) produces but a single drupe, and this has commonly but one seed within the "stone"; though occasionally as in "philopena" almonds both of the ovules develop. It should be noted that neither the "stone" of a peach, plum, or cherry nor the "shell" of an almond is part of a seed, but is the hardened inner layer of the pericarp, enclosing a seed or seeds. The torus of quince (Cydonia) and of apples and pears (Pyrus), envelops the gyncecium, is adherent to the com- pound ovary, and both ripen together into the kind of fruit called a pome ^ in which the seeds are enclosed in a "core" consisting of dry, more or less parchment-like pericarps, surrounded by the fleshy torus. An adherent torus envelop- ing the ovary is said to be epigynous,^ a term likewise applied to the stamens, or the floral envelopes which it bears; and, indeed, to the flower itself having such a torus. The ovaries of epigynous flowers are termed inferior. A typical formula for the family is shown on pages 408, 409, The family includes plants of various habit; without milky, colored, or acrid juice, and lacking reservoirs of volatile oil; but having often fragrant flowers more or less like those of the crowfoot family, but perigynous or epigynous; mostly stipulate leaves, and frequently luscious fruit. 113. The pulse family (Leguminosas) . Examples: pea- nut (Fig. 33, page 45), pea (Figs. 37, 38, page 48), beans 1 Ad-here' < L. ad, to; hoerere, stick. 2 Pome < L. poynum, an apple or similar fruit. T! C/ < ' Ep-ig'y-nous < Gr. epi, upon; gyne, pistil. T^] 3G6 VARIOUS PLANT GROUPS (Figs. 39, 40, pages 49-51), gum arable tree (Fig. 156, page 164), tragacanth shrub (Fig. 157, page 165), licorice (Fig. 162, page 169), locust (Fig. 182, page 197), courbaril- tree and Zanzibar copal-tree (Fig. 273, page 289), indigo shrub (Fig. 275, page 293), and logwood-tree (Fig. 276, page 294). See on pages 408-411 the formulas given for Acacia, Ha;matoxy- lon, Hymensea, Trachylobium, Pisum, Phaseolus, Rol)iiiia, Indigo- fera, Glycyrrhiza, Astragalus, Arachis, and Leguniinosse. In their floral structure many acacias, like the gum arable tree, approximate closely to certain members of the rose family, notably in the numerous stamens, and regular calyx and corolla. In some species the filaments are more or less coaleseent. Stamens thus united are said to be monadel- phous.^ The logwood-tree (Hamatoxylon), the courbaril- tree (Hymensea) and the Zanzibar copal-tree (Trachylobium) present irregular corollas, with the peculiarity that the uppermost petal is at first enfolded by the side ones, and these in turn by the lower pair. A large majority of the family, represented by peas (Pisum), beans (Phaseolus), and the other examples referred to, have what is called a papil- ionaceous 2 corolla. This consists of five petals: one com- paratively large called the standard, which is above the others and enfolds them in the bud; two side ones called the wings; and two lower ones grown together to form what is called the keel. A curious condition of the androecium commonly found with the papilionaceous corolla is that there is one uppermost stamen free from the other nine which are more or less coaleseent. Such an androecium is t(Tmed diadelphous.^ Another peculiarity usually accompanying the papilionaceous corolla is the irregularity and coalescence of the sepals to form a calyx described as gamosepalous * and bilabiate,^ that ' I\Ion"a-dcrphous < Gr. monos, one; addpJios, a brother; meaning in one brotherhood; indicated by the small i)arenthesis. - Pa-pil"i-on-a'ccous < L. papilio, a butterfly— from the resem- blance. This is expressed in the formula by P"5+ j). ^ Di"a-derphous < Gr. dis, two; FA^). * Gam"o-sep'al-ous < Gr. gamos, union; S'. 5 Bi-la'bi-ate < L. bis, two; labium, lip; S5;. THE LINDEN FAMILY 367 is to say, consisting of sepals more or less united, so as to form an upper and a lower lip. The most distinctive peculiarity of the family is its typical fruit, called a legume.^ This consists of a single carpel which becomes dry and normally splits into two valves by dorsal and ventral sutures. As in the mustard family we found that the radish has an indehiscent pod of two carpels which is essentially a silique in structure, so here in certain genera we find pods of one carpel, essentially legumes, but without the usual mode of dehiscence. Peanuts, for example, though indehiscent, are plainly like pea-pods in most important re- spects, and both may well be called legumes. A still stranger modification of legume is the fruit of Hsematoxylon which dehisces into two valves but along lines midway between the ventral and the dorsal sutures, as indicated by C/ <> . The great majority of our wild or cultivated members of the pulse family may be recognized by their having mostly 'papilionaceous, or at least irregular corollas, and a single carpel ivhich forms a legume, ivhile in other respects these plants are similar to those of the rose family. 114. The rose order (Resales) includes several families which agree for the most part with the rose and the pulse family in bearing hotryose inflorescences of usually complete perigynous flowers, regular or irregular, having petals at least partly distinct, and pistils with a ventral or axile place^ita. These features are indicated in the formula of Resales on pages 410, 411. 115. The linden family (Tiliaceae.) Examples: jute (Figs. 218 I, II, page 232), and linden (Figs. 251, 252, page 264). Sec the formulas of Corchorus, Tilia, and Tiliaceae on pages 410, 411. The bracts of lindens (Tilia) and the androecium and fruit of the family present the chief peculiarities which call for present notice. The bracts of jute (Corchorus) present 1 Leg'ume < L. legumen, beans, etc., or that which may be gathered by hand without cutting < legere, gather. Its sign is C/ 0 • 368 VARIOUS PLANT GROUPS no special peculiarities. In lindens, however, the lowermost bract of the flower-cluster is large, forming a sort of involucre, and adheres for a considerable distance to the peduncle. Jute flowers, which have the stamens in two whorls of five each, thus conforming to the numerical plan of the other floral organs, afford the simplest condition. In other species the stamens appear to be indefinite in number, but close examination would show them to be grouped into five clus- ters opposite the five petals. Each cluster is taken to repre- sent the branches of a single.one of the inner whorl of stamens, in much the same way that a pair of long stamens in the mustard family represent, as we have seen (section 110), a single branched stamen. The fact that the stamen-groups are opposite the petals (hence regarded as being of the inner stamen whorl) is expressed by placing the sign 1 1 between P and FA. Stamens in five clusters are said to be pentad elphousA The stamens of the linden are always pentadelphous, and sometimes each cluster includes a staminode to which the anther-bearing filaments are coalescent. Throughout the family two pollen-sacs are borne by each filament which, however, divides more or less at the tip into a short stalk for each sac. The fruit of jute is a capsule dehiscing by dorsal sutures into valves attached to the radial partitions. Such dehiscence is called locuUcidal.^ In lindens onlj^ one of the five carpels ripens, and commonly only one of the seeds which it contains. The pericarp becomes somewhat drupaceous so that the product of each flower resembles a small round almond. But a cluster of these nut-like fruitlets is formed by each in- florescence, and this cluster, borne on a common peduncle to which the bract still adheres, separates at maturity as a whole from the tree. The dry bract serves excellently as a ' Pen"-ta-derphous < Gr. pente, five. FA oo -=- 5, - Loc'u-li-ci"dal < L. loculus, a compartment; coedere, cut, because it is as if each compartment were cut into, so that in cross-section each division has a form something Uke the sign J_ which is used to distin- guish this type of capsule in the formula of Corchorus. THE MALLOW FAMILY 369 sail to carry the fruit-cluster before the wind over smooth ground or a crust of snow. The family comprises mostly woody plants having mucilag- inous juices; and often fragrant flowers with petals imbricate and distinct; staynens numerous, pentadelphous, and free; anthers with two pollen-sacs; and styles coalesced throughout. 116. The mallow family (Malvaceae). Examples: cotton (Figs. 214-216, pages 225-227) and marshmallow (Fig. 158, page 166). See pages 410, 411 for formulas of Gossypium, Althaea, and Malvaceae. Several new features are presented in this family. An involucel is commonly present close to the flower, recalling the epicalyx of strawberries, but here we have bractlets in place of stipules. The aestivation of the corolla is such that one edge of each petal overlaps its neighbor, while the other edge is in turn overlapped by the next in order, vEstivation of this type is termed convolute.'^ The androecium appears to consist of a number of stamens borne upon a long tube enclosing the styles. This tube shows at the top, more or less distinctly, five projections which give evidence that the androecium consists really of but five stamens coalesced by their filaments to form the tube, and branched above into the numerous stalks liearing pollen-sacs. Curiously enough each branch bears only a single pollen-sac and is thus equiva- lent to but half of an ordinary anther. The expression FA oo -^5)] would read "stamens numerous, divided into five groups, monadelphous, and adhering to the petals." As a result of this adhesion the petals, although distinct, fall off in connection with the stamen-tube (as the fruit ripens) much as if they were coalescent. The fruit of marshmallow (Althaea) represents a type very common in the family. Although indehiscent, the basal part of the several carpels, as they ripen, separate into as many nutlets, each containing a single seed. The fruit thus returns to a condition very like that of a cluster of anemone 1 Con'vo-lute < L. con, together; volvere, roll. P" is the sign. 370 VARIOUS PLANT GROUPS achenes. A fruit thus splitting into one-seeded pieces is called a schizocarpJ The family comprises mostly herbaceous plants rich in muci- lage; with flowers often involucellate, seldom fragrant; petals convolute and distinct; stamens numerous, monadelphous, adhering to the corolla; anthers with only one pollen-sac; styles more or less distinct. 117. The mallow order (Malvales) contains several families having mostly cymose inflorescences of complete, regidar, and hypogijnous flowers; with the petals distinct {though often ad- hering to the pentadelphous or monadelphous stamens) and opposite the stamen-groups; and the pistils with axile placentce. See pages 410, 411 for a typical formula of the order. 118. The parsley family (Umbelliferae) . Examples: car- rot (Figs. 47-53, pages 55-57), parsnip (Figs. 54, 55, page 57), celery (Figs. 78, 79, page 75), parsley (Fig. 138, page 140), caraway (Fig. 140, page 142), anise (Figs. 141 I, II, page 142), coriander (Figs. 143 I-III, pages 143, 144), asafetida (Fig. 168 I, page 175), water hemlock (Fig. 179, page 193), and poison hemlock (Figs. 180 I, II, pages 194, 195). See pages 410^13 for formulas of Conium, Carum, Petroselinum, Cicuta, Coriandrum, Apium, Pimpernella, Pastinaca, Ferula, Daucus, and Umbelliferae. The name Umbelliferse, meaning "umbrella-bearers," was given to this family because almost all the members have inflorescences reseml)ling umbrellas. This form of in- florescence, called an umbel;- ma}^ be likened to a raceme in which the internodes of the rachis are suppressed, thus bring- ing the bracts, when present, together as an involucre. In most of the parsley family, the inflorescence consists of a number of little umbels or umhellules,^ arranged in an umbel. Usually all the flowers of a cluster are perfect. An interest- 1 Schiz'o-carp < Gr. schizo, I split ; karpos, fruit. C/ < -i- oo . ^ Um'bel < L. umbelln, diminutive of umbra, shade. I/. ' Um'bel-lule < L. umbellula, diminutive of umbelln. i/. Each uin- bellule may have a .secondary invohicre composed of secondary bracts which are sjanbolized by the B- which comes after the B. THE PARSLEY ORDER 371 ing exception is found in tlie carrot (Daucus) where there is often a central fiower destitute of essential organs. Such a flower is described as neutrals The sepals are commonly reduced to small tooth-like projections, or they may be so united into a narrow ring as to appear obliterated. The calyx-teeth do not touch in the bud; hence their aestivation is said to be open.- More or less irregularity of calyx and corolla occurs among the outer flowers of an umbel, though most of the flowers are but little if at all irregular. The two-carpelled, inferior ovary ripens into a dry fruit which at maturity splits in halves, each half hanging from the top of a continuation of the torus, as shown in Fig. 141 II. Such a fruit is called a cremocarp.-' It is like a schizocarp except that it is the product of an inferior ovary. Each half has several more or less pronounced ribs; and, in the wall, parallel to the ribs, are often tubular reservoirs of volatile oil giving a characteristic odor to the fruit. An odor similar to that of the fruit often pervades every part so that from an immature specimen or only a fragment it is often possible to recognize these plants by their peculiar, though indescribable, smell. The stems have the rare characteristic of being hollow even at the nodes. Herbs rich in volatile oil, but with watery sap; having leaves exstipulate; flowers regular or irregular, mostly in compound umbels, often involucrate; the petals and stamens five, the carpels two, styles distinct; and the fruit a cremocarp — such are the typical members of the family. 119. The parsley order (Umbellales or Umbelliflorae) in- cludes two other families which agree with the parsley family- in having mostly umbellate inflorescences of small, complete, epigijnous flowers, with the petals and sta7?iens distinct and alternate, and the carpels with but a single ovule in each. For the formula of Umbellalles see pages 412, 413. ^ Symbolized by the sign 6- - Expressed in the formulas by S". ^ Crem'o-earp < Gr. krerrmo, I hang; karpos, fruit. TCi <^ -r- 2. 372 VARIOUS PLANT GROUPS 120. The buckwheat family (Polygonaceae). Examples; buckwheat (Pig. 22, page 29) and rhubarbs (Fig. 112, page 104, and Fig. 163, page 170). See pages 412, 413 for formulas of Rheum, Fagopyrum, and Poly- gonaceae. The stems of plants belonging to the buckwheat family are commonly swollen at the joints, and have above each node a thin tubular sheath formed by the coalescence of the stipules. These sheaths are called ocrece,^ and the plants or leaves are said to be ocreate. The parts of the flower are commonly in threes although there are some curious departures from the type. Thus in buckwheat (Fagopyrum) there are five sepals as against the six-leaved perianth of rhubarb (Rheum), but we may regard the missing sepal as represented by a bractlet which is ab- sent in the other inflorescence. Again, the six outer stamens of rhubarb are to be regarded as three pairs, each pair formed from the division of one stamen into two; while in l^uckwheat the androecium is similar except that one of the outer stamens has remained undivided, thus giving but eight in all. That there are three carpels is shown clearly by the three distinct styles, though there is but one cavity from the base of which arises a single ovule. This ovule differs from the others we have studied in having the micropyle oi)posite to the funicle, that is to say, in being straight or ortJtotropous.- The family consists mostly of herbs ivith a watery juice which is often peppery and sometimes pleasantly acid, without reservoirs of volatile oil; having stems often swollen at the joints; leaves ocreate; styles two or three, distinct; ovary containing a single, orthotropous ovule; and the fruit an achene. 121. The buckwheat order (Polygonales) which con- tains only the above family, may be contrasted with the previous orders as having mostly paniculate inflorescences of small, regular, perfect, hypogynous flowers, with the perianth, ' Oc're-a < L. a legging. LJ.). ^ Or-thot'ro-pous < Gr. orthos, straight. Symbolized by a straight line over the numerical sign, Ei. THE BIRCH FAMILY 373 leaves, and stame7is distinct and alternate, and the ovary with but one cavity and one ovule. The formula of Polygonales is given on pages 412, 413. 122. The birch family (Betulaceae) . Examples: filbert (Fig. 23, page 3G) and birch (Fig. 254, page 265). See pages 412-415 for formulas of Betula, Corylus, and Betula- ceae. We meet in this family with the singular form of inflores- cence sometimes called "pussies," or catkins, and known botanically as aments.^ An amentaceous inflorescence is typicall}^ an elongated, often dangling, cluster of imperfect flowers which are in the axils of scale-like bracts. It is a special form of spicate ^ inflorescence, spike ^ being the general term for a racemose cluster of sessile or nearly sessile flowers. If the internodes of a spike fail to elongate the flowers become crowded into a head or capitate ' inflorescence. In the axil of each scale of a birch catkin we find three flowers (Fig. 254) closely crowded together and so forming the simplest sort of head. These heads of staminate flowers are borne along the sides of a slender hanging rachis, so that the whole compound cluster forms a typical ament. The pistillate heads occur on a stiffer rachis which commonly grows erect, and might therefore properly be called a spike although on account of its scale-like bracts ])otanists often speak of this inflorescence as a pistillate ament. In the pistillate inflores- cence of hazels (Corylus) the little heads (here two-flowered) are so few and crowded as to form a compound head of heads.* In the hazels the staminate flowers are solitary in the axils of the scales, thus forming simple aments; while the pistillate flowers are grouped in heads of two, and each flower is sur- rounded b}' an involucel formed of its special bract and its ^ Am'ent < L. amentum, a thong or shoestring. Ij. 2 Spi'cate, spike < L. spica, an ear of corn. !=. ^ Cap'i-tate < L. capitalus, having a head < caput, head. I". * All these facts are expressed in the formulas by using an inverted exclamation point as the symbol of an amentaceous inflorescence, an inverted colon for spicate, and two inverted periods for capitate clusters. That the bractlets are adherent to the bracts by their lower parts is shown by the small bracket, j. 374 VARIOUS PLANT GROUPS two coalescent and adherent bractlets. Plants with both staminate and pistillate inflorescences borne upon the same individual plant are termed monoEcious.^ The united bracts and bractlets of birches (Betula) ripen into dry scales forming a cone-like cluster of fruits made up of little samaras. In hazels the involucre becomes much enlarged in fruit, and each surrounds a much hardened peri- carp which because of its hardness and indehiscence is called a nut^ The family comprises woody 'plants without oil reservoirs but with resinous icarts or hairs on the younger parts; simple, stipulate leaves; and monoecious inflorescences, the staminate amentaceous, the pistillate in spikes or heads with coalescent bracts and bractlets, and the pistils of two carpels with axile placentae. 123. The beech family (Fagaceae). Examples: chest- nut (Figs. 24-26, pages 37, 38), oaks (Figs. 242, 243, 267, pages 257, 258, 277), and beech (Fig. 257, page 268). See pages 414, 415 for the formulas of Fagus, Castanea, Quercus, and Fagacese. The inflorescences of this family resemble those of the preceding family in being monoecious and in part amenta- ceous. It is in the bracts and the way they are borne that we find the most significant differences — differences which become more striking as the fruit matures. Indeed, bot- anists have here met with a morphological problem of more than ordinary difficulty in the preliminary question: What are the homologues of bracts which ripen with a beechnut, a chestnut-bur, or an acorn? In the staminate inflorescences of beech (Fagus) and chest- nut (Castanea) the bracts are obvious enough and are suffi- ciently like those of the birch family to require no special 1 Mo-noe'cious < Gr. monos, one; oikos, household. This is indi- cated by cf-9 . If the staminate inflorescence differs in form from the pistillate the nature of each is shown by placing the inflorescence signs in corresponding order, i. e., beginning with the staminate. Thus li-i" would read "staminate inflorescence amentaceous, the pistillate spicate, both compounded of heads." 2 In the formula this extra hardness of the pericarp is indicated by two inverted exclamation points. THE BEECH FAMILY 375 comment; while the staminate flowers of Quercus are ebrac- teate. The -pistillate flowers of beech are two in a head (Fig. 257) which is enclosed in a little cup or cupule ^ as it is called, bearing scales or spines on its outer surface. This cup eventually encloses completely the ripening nuts, and when mature splits into four partial valves to set them free. The cupule of chestnuts encloses three flowers, ripens into the spiny bur, and splits sometimes into four valves, and sometimes irregularly. Only one flower is in the scaly cupule of oaks (Quercus), and the single nut which constitutes the acorn is so little covered by the cupule as to make splitting of the cupule unnecessary. Evidently the projections of the beech cup, the spines of the chestnut-bur and scales of an acorn-saucer are homolo- gous, as is also the main part of the cupule of each. But where are the bracts? Do the four divisions of the ripened beech cup and chestnut-bur correspond to so many bracts which in the acorn-saucer remain coalesced? In that case the various outgrowths from the cupule w^ould be regarded as mere projections like the spines on a leaf. This view is held by many botanists. Others maintain that the projections, spines, and scales are the free tips of bracts which have coal- esced by their bases to form the body of the cupule. On this view the cupule would be an involucre of many instead of but four bracts. A third view regards the main body of the cupule as stem, that is to say, as a cup-like development of the secondary peduncle, bearing numerous bracts. Thus regarded, the acorn scales, the beech-nut projections, and the branched sjiines of the chestnut-bur, are homologized with bracts which are entirely distinct and free from the concave inflorescence-stalk. This last theory seems to be the one most easily reconciled with the facts as they appear in other members of the family as well as in those we have studied. ^ ^ Cu'pule < L. cupula, diminutive of capa, cup. - This is the view adopted in our formulas, i does duty for the axial part of the ultimate inflorescences; //^ following shows that it become.*? woody and cancave like a perigynous torus; while C 4 shows that it dehisces into four valves; or < that it is indehiscent; and BI °° that it bears numerous dry bracts. The other parts of the formulas should be readily understood from what has preceded. 376 VARIOUS PLANT GROUPS The family consists of ivoody plants without oil reservoirs or resinous excretions; but ivith simple, stipulate leaves; and monoecious inflorescences, the staminate mostly amentaceous, the pistillate more or less enclosed in a cupule, which hears dis- tinct, scaly, or spiny bracts; and the pistils of three or more carpels with axile placentce. 124. The beech order (Fagales) comprises only the birch and the l^ecch families. These agree in having moncecious inflorescences with the statninate flowers mostly in aments, and the pistillate in spikes or heads; the flowers hypogynous or epigynous; the perianth leaves and stamens distinct and alternate; and the ovary with axile placentae, and more or less completely divided into two or more cavities, all but one of which becomes obliterated in the fruit. See pages 414, 415 for the formula of Fagales. 125. The walnut family (Juglandaceae). Examples: wal- nut (Fig. 27, page 39), butternut (Fig. 28, page 40), pecan (Fig. 29, page 40), hickory (Fig. 30, page 41), and black walnut (Fig. 246, page 260). Formulas of Juglans, Carya, and Juglandacese are given on pages 414, 415. In general appearance the inflorescences of the walnut family resemble those of the beech and the birch families, but there is a curious adherence between the bracts, bractlets, and perianth leaves, unlike anything we have seen. Those which belong to each flower are all more or less united to form what at first sight might be mistaken for perianth alone. The fruit is mostly a drupaceous nut recalling the almond, but with the tough fleshj^ part dehiscing into four valves and differing also in having the epigynous torus as a component part. The walnut family may be distinguished as consisting of ti^ees ivith scented, pinnately compound, exstipulate leaves; and monoecious inflorescences, the staminate amentaceous, the pis- tillate in heads; each pistil of two carpels; and the fruit a de- hiscent drupe with a nut-like stone. 126. The walnut order (Juglandales), contains only the THE CROWFOOT SERIES 377 family from which it derives its name. It is distinguished from the other orders with monoecious inflorescences, staminate amcnts and pistillate heads, by having the -perianth leaves or the epigynous torus adherent to the bractlets and bract of each, and the ovary with but one cavity and one ovule. The formula of Juglandales is given on pages 414, 415. 127. The willow family (Salicaceae). Examples: willow (Figs. 228 I, II, pages 243. 244) and poplar (Fig. 253, page 264). Formulas of Populus, Salix, and Salicacese are given on pages 414, 415. Much simpler flowers are here show^n than any previously mentioned, although scarcely any new features are pre- sented. The torus while cup-like in the poplars, is represented in the willows by one or two glandular projections which secrete nectar. It is plain that a cup divided, or failing to develope, at one or two places would be reduced to such flat projections. A peculiarity of the fruit of both genera is that its two carpels dehisce along their dorsal sutures exposing the small hairy seeds to the wind. This family which contains only the two genera mentioned, is composed of icoody plants without oil reservoirs, but some- times with aromatic resinous secretions; the leaves simple and stipidate; the inflorescences amentaceous and dioecious; the pistil of two carpels with parietal placentce; and the fruit a capsule ivith numerous tufted seeds. 128. The willow order (Salicales) contains only the above family. Dioecious aments of flowers withoid perianth but with numerous ovules, perigynous (?) torus, and free bracts, distin- guish this from the other orders. The formula of Salicales is given on pages 416, 417. 129. The crowfoot series (Archichlamydeae). A general view of all the orders which we have thus far studied shows them to agree (with but rare exceptions) in having no coales- cence among the petals. All the leaf-parts of any flower are at first similarly distinct as they arise in the bud. Some- 378 VARIOUS PLANT GROUPS times petals do not appear at all, hut when they do it is as distinct projections from the torus, comparable to the first rudiments of foliage leaves as they form near the tip of a developing shoot. The same is true of sepals, stamens, and carpels, as illustrated in Figs. 298, 299 I. If, however, a gam- osepalous calyx, a monadelphous androecium, or a compound pistil is to be produced, it happens sooner or later that those jft/AA jHi- Fiu. 298. — Flower of Rose {Rosa alpina, Rose Faniilj-, Rosacea) iu early stages, cut vertically and enlarged. A, the sepals (A-) are well de- veloped, but the petals (c) and the stamens (a) are just appearing as minute knobs. B, sepals, petals, and stamens further advanced; and the pistils (g) just appearing as knobs on the dome of the stem-tip. C, later stage. D, still later stage in which the parts are still developing in the bud. (Payer.) parts of the ring which connect the original projections begin to grow and the distinct parts are carried up on the rim or the tip of a tube or united mass of organs. Flowers which as they develop retain the original distinct- ness of their petals, or which develop none at all, are termed archichlaniydeous.^ Such flowers, we have seen, characterize the crowfoot series which includes all the orders we have studied and a number of others resembling them in the pe- culiarity noted. 130. The heath family (Ericaceae). Examples: wintergreen ' .\r"ohi-clila-my(l'o-ou.s < Gr. archi, first; chlnmys, mantle; imply- ing that the corolla, likened to a mantle, retains its original condition. VARIOUS PLANT GROUPS 379 (Fig. 147, page 148), mountain laurel (Fig. 189, page 202), and sheep laurel (Fig. 190, page 202). Formulas of Gaultlieria, Kalmia, and Ericaceae are given on pages 416, 417. A corolla with the petals coalesced, as in the examples here given, is termed gamopetalous,^ a corolla with cUstinct petals being choripetalous.- When anthers open by pores the dehiscence is said to be poricidal as in the case of capsules which open similarly. It will be noticed that the capsule of mountain laurel (Kalmia) dehisces by splitting through the partitions. Such dehiscence is cUstinguished as septici.dal.^ The fruit of wintergreen (Gaultheria) is peculiar in having a loculicidal capsule enveloped in a fleshy enlargement of the calyx and torus. The typical members of the family are woody plants, often aromatic; having simple, exstipulate leaves; and perfect, gatno- petalousfloivers, with poricidal stamens, and a compound pistil, superior or inferior ovary and axile placentce; the fruit being capsular, or berry-like. 131. The heath order (Ericales) includes several families associated with the above through having rnostly regular and perfect, usually gamopetalous flowers, four to ten stamens nearly or quite free, the anthers mostly poricidal, and the ovary compound, with axile placentce. The formula for Ericales is given on pages 416, 417. 132. The morning-glory family (Convolvulaceae) is well exemplified by the sweet potato (Figs. 56, 57, pages 58, 59). Formulas of Ipomoea and Convolvulaceae are given on pages 416, 117. The new features to be noted here are the aestivation of ' Gam"o-pet/al-ous < Gr. gamos, union; petalon, flower-leaf. P). - Cho"ri-pet'al-ous < Gr. choris, separate. ^ Sep'ti-ci"dal < L. tseptum, partition; coedire, cut. Indicated by the sign^. 380 VARIOUS PLANT GROUPS Fig. 299, I. — Flower of Oxcye (Heliopsis scabra, Sunflower Family, Composite). A~N, stages in the development of a tubular floret, enlarged. A, very young stage in which the' flower [fl) is as yet with- out petals but is plainly dis- tinguishable from its bract (6). B, shows the ringlike swelling (A:) which represents the calyx, and five knobs (c) which are the beginnings of petals. C, a somewhat more advanced stage, just before the appearance of stamens. Z), showing the stamens (a) just appearing. E, same stage as D, cut vertically. F, later stage in which the beginnings of two carpels {g) appear. G, same stage, viewed from the side, show- ing that the petals or corolla lobes have curved inward protectively and are united below by a ring of tissue which by upward growth be- comes the corolla-tube bear- ing the five lobes above. H, same stage, cut vertically; showing the upward growth of the carpels i,g) leaving a hollow in the stem-tip (torus). J, later stage, cut vertically through the middle of the carpels (g) showing a deepen- ing of the hollow in the torus. K, bud of middle age, show- ing the corolla-tube (c) with its five lobes well developed, and lower part of the pistil (g), enveloped by the torus, becoming plainly distinct as an "inferior ovary." L, a somewhat later stage, cut ver- tically, showing the appear- ance of two styles (s) , still dis- tinct, and a young ovule (o) with its outer coat half-grown. M, bud almost ready to open; the two styles having grown into one (s); the anthers (a) joined into a tube; the sepals (k) distinct prominences on the top of the torus, a nectar- gland (d) ; and the ovule (o) completely formed. -V, Tubular floret, open, showing anther-tube (a), corolla-tube (c), and inferior ovary (g). OS, stages in the growth of a ray-floret. O, very early stage in which five petal-lobes appear, three of which, however, are distinctly larger than the other two. P, later stage in which the three larger lobes (c) have become much larger, while the two smaller ones have remained undeveloped. Q, ray-floret about half-grown, showing two of the three petal-lobes separate to the base. R, same, cut vertically between the two separate petals, showing the union of the middle one (at the THE MORNING-GLORY FAMILY 381 Fig. 299, II. — Creeping Bellflower (Campanula rapunculoidcs , Bellflower Family, CampanulacecE) . A, flowering branch. B, flower, cut verti- cally, enlarged. C, floral diagram. D, fruit opening by little doors at base, enlarged. E, seed, entire, and cut vertically, enlarged. (Le- Maout and Decaisne.) — -A perennial herb 30-90 cm. tall; flowers blue; fruit dry. Native home, Eurasia; run wild from gardens. the corolla and the dehiscence of the capsule. So complete is the coalescence of the petals in most members of the family and so flaring the corolla, that as it forms in the bud it be- comes folded or plicate,^ and the folds overlap in a convolute manner. Such iestivation may be described as 'plicate- convolute. The capsule of the morning-glory (of which the sweet potato is one species) differs from the other capsules we have studied in having the valves separate not only from one Pli'cate < L. plicatus, folded into plaits. P"'. left) with one of the other two which together with the middle one are to form the strap-shaped corolla. S, somewhat later stage showing the three lobes of the strap-shaped corolla (c) and the inferior ovary (g). (Payer.) — A perennial herb about 1 m. or more tall; resembling a sun- flower. Native home. Eastern United States; familiar in gardens. 382 VARIOUS PLANT GROUPS another but from the partitions within, the sutures coming at the margin of the partitions. Dehiscence of this type is termed marginicidally septifragal. ' The family is a small one made up mostly of round-stemmed herbaceous vines, with more or less milky juice; alternate, ex- stipidate leaves; regular flowers having a gamopetalous corolla, plicate-convolute in the hud, and having usually adherent stamens, the ovary being two to five-celled; and with the fruit, commonly a capsule, containing a few large albuminous seeds with folded embryo. 133. The nightshade family (Solanaceae). Examples: white potato (Figs. 58 I-III, pages 59, 60), tomato (Figs. 88, 89, pages 83, 84), egg-plant (Fig. 90, page 85), red pepper (Figs. 125 I, II, 126, pages 131, 132), tobacco (Fig. 173, page 184), belladonna (Fig. 175, page 187), and jimson-weed (Figs. 1871, II, page 200). No new signs appear in the formulas of Nicotiana. Datura, Atropa, Capsicum, Solanum, and Solanacese on pages 416, 417. This large family may be distinguished as consisting of mostly rank-scented, round-stemmed, herbaceous plants, with watery sap; leaves alternate, exstipulate; flowers regular or nearly so; the corolla gamopetalous, plicate-convolute, or plicate- valvate; ovary two-celled; fruit a capsule or berry containing many small albuminous seeds with the embryo coiled. 134. The figwort family (Scrophulariaceae) is exemplified by the foxglove (Fig. 192, page 204). See the formulas of Digitalis and Scrophulariacea^ on pages 416, 417. Round or square-stemmed, herbaceous or woody plants not strongly scented; the juice watery and often bitter; leaves alter- nate, opposite or verticillate, exstipulate; flowers irregular; corolla gamopetalous, imbricate in aestivation; stamens two to five, mostly four ; ovary two-celled ; fruit a septicidal or loculicidal capsule, containing many small albuminous seeds with the embryo uncoiled. 1 Sep-tif'ra-gal < L. septutn, partition; /ranjere, break. Cj -p. THE (lOURD FAMILY 383 135. The mint family (Labiatae). Examples: sage (Figs. 132, 133, ])age 138), thyme (Fig. 134, page 139), spearmint (Fig. 135, page 139), summer savory (Fig. 136, page 139), sweet marjoram (Fig. 137, page 140), and pepper- mint (Figs. 146 I, II, pages 147, 148). The formulas of Mentha, Thymus, Origanum, Satureia, Salvia, and Labiatse are given on pages 418, 419. When a gamopetalous corolla has the two upper petals coalescing with one another more complete!}^ than they do with those at the side, and the two lateral ones in turn more completely coalescing with the lower petal, there results a two-lipped or labiate ' form shown especially well in Salvia and most other members of the family. It should be noted, however, that more or less labiate corollas occur also in many genera of the figwort family and some other families of the group we are now studying. Typical members of the mint family are easily recognized as square-stemmed, aromatic herbs with opposite leaves, labiate corolla and schizocarpic fruit of four nutlets. As in the figivort family the juice is watery, the leaves exstipulate, the petals imbricate, and the stamens generally four, but the seeds are exalbuminous and the embryo uncoiled. 136. Phlox order (Polemoniales or Tubiflorae) , embraces a number of families besides the four just mentioned. In general they are characterized by having perfect, regular or irregular, gamopetalous flowers, with two to five stamens ad- herent to the corolla, and distinct; the anthers seldom poricidal; the ovary compound and superior. For the formula of Polemoniales see pages 418, 419. 137. The gourd family (Cucurbitaceae) . Examples : pump- kin (Figs. 80 1-81 I, pages 76-78), squashes (Figs. 81 II- 84, pages 79-82), cucumber (Figs. 85-87, pages 82, 83), muskmelon (Figs. 102, 103, page 95), watermelon (Figs. 104, 105, page 96), sponge cucumber (Fig. 225, page 240), and bottle-gourd (Fig. 265, page 275). See pages 418, 419 for the formulas of Cucurbita, Cucumis, Citrullus, Lagenaria, Luffa, and Cucurbitaceie. ^ La'bi-ate < L. labium, lip. P5). • 384 VARIOUS PLANT GROUPS Most of the gourd family have the androecium so curiously developed as to be quite variously understood by different botanists. According to the view now most generalh' adopted there are typically five stamens. In some members of the family (not among the above examples), all five stamens are free, but usually four of them coalesce more or less completely in pairs, forming, as we may say, two double stamens leaving an odd one distinct. In such cases the flowers appear to have but three stamens. Along with this coalescence there goes an extraordinary elongation and bending ' of the pol- len-sacs as shown in Fig. 80 III. In some genera, as for example squashes, etc. (Cucurbita), there is a complete coalescence of all the anthers, which are then said to be syngenesious."^ In this genus and most other members of the family, three, much thickened, wedge-shaped, parietal placentie almost completely fill the ovary, and bear on their recurved margins an indefinite number of ovules. The seeds as they ripen are imbedded in a soft pulp formed of the placentae. Around this pulp, in the mature fruit, is a hard rind composed of the ripened ovary wall and the adhering torus. Such a fruit is called a pepo.^ The family is made up mostly of herbaceous vines with wa- tery juice; flowers solitary or loosely clustered, imperfect, reg- ular, gamopetalous or choripetalous; sfai?iens five, often appear- ing as three through coalescence, and sometimes syngenesious, the pollen-sacs often elongated and bent; ovary inferior with three parietal placenta, fruit usually a pepo. 138. The bellflower family (Campanulaceae). Examples: Indian toliacco (Figs. 188 I, II, page 201) and bellflower (Fig. 299 II, page 381). The formulas of Campanula, Lobelia, and Campanulacese are given on pages 418-421. The corolla of Indian tobacco and other species of its genus ' This bending is expressed in the formulas by FA '*' . 2 Syn"gen-e'sious < Gr. .s(/«, together; genesis, generation. Such coalescence is symbolized by a small parenthesis placed after the stamen number and above. ^ Pe'po < h' pepo, a pumpkin. Tdj <. THE SUNFLOWER FAMILY 385 (Lobelia) affords a case of partial coalescence somewhat dif- ferent from any of our foregoing examples. The two upper- most petals arc entirely free from one another, though coal- esced with the side ones, and these with the lowest, so that all five petals are as if united into a tube which is split down the back.i In bellflowers (Campanula) the more or less bell-like corolla from which they take their name shows no irregularity. Mostly herbs with milky juice; flowers solitary or loosely clustered, perfect, regular or irregular, viostly gamopetalous ; stamens five, free or monadelphous and syngenesious; the pollen- sacs straight; ovary inferior with two to five axile placentre; fruit capsular. 139. The sunflower family (Compositae). Examples: Jerusalem artichoke (Figs. 59 I-IV, pages 61, 62), lettuce (Figs. 75-77, pages 72-74), and wormwood (Fig. 155, page 160). Formulas of Helianthus, Lactuca, Artemesia, and Composite are given on pages 420, 421. More than a tenth of all the species of flowering plants belong to this the largest family of seedworts. The very characteristic inflorescence is sometimes mistaken for a single flower, and was indeed called a "compound flower" by the early botanists. In reality, as will be readil}" seen, the small flowers are borne on a more or less flattened expansion of the peduncle, called the receptacle, and form a compact head surrounded by an involucre of bracts resembling sepals. As if to increase the deception the outer row of florets often have what are called strap-shaped corollas formed by a coalescence of the petals into one flat piece (Fig. 59 II, III), somewhat as in the Indian tobacco but more complete; and these corollas radiate so as to look like petals. The inner part of the head in such cases as the sunflower is made up of regular florets (Fig. 59 III). Many members of the family have only regu- lar florets, while still others have all the florets strap-shaped or sometimes labiate. The calyx may consist of a few papery scales, or of numer- ^ This condition is indicated in the formulas by P" 3). 386 VARIOUS PLANT GROUPS ous bristles forming what is termed the pappus.^ Sometimes through a prolongation of the torus above the fruit a sort of parachute is formed as in lettuce (Lactuca, Fig. 76). The one-seeded fruit of Compositae is commonly called an achene, although morphologically it is very different from such a simple achene as that of the crowfoots. In spite of wide diversities in structural detail the members of this vast family may generally be recognized as herbs with milky or watery juice; flowers in dense heads having a calyx-like involucre, gamopetalous, regular or irregular; stamens five, syngenesious, but with distinct filaments inserted on the corolla, and the pollen-sacs straight; ovary inferior, with a single ovule; fruit achenial, often loith pappus. 140. The bellflower order (Campanulales), includes several families with flowers perfect, imperfect, or neutral, regular or irregular, mostly gamopetalous; the stamens five, adherent to the corolla, distinct or more or less coherent; anthers not poricidal; ovary compound, inferior. The formula of Campanulales is given on pages 420, 421. 141. The bellflower series (Metachlamydeae) in contrast with the crowfoot series or Archichlam^^deae, includes several orders which are characterized by the prevalence of a gamo- petalous corolla. This, as showing a more advanced develop- ment of the perianth than we find in archichlamydeous flowers (see section 129), entitles the flower possessing it to be dis- tinguished as m.etachlamydeous:- 142. The dicotyl sub-class (Dicotyledones) comprises the crowfoot series (Archichlamj'dea?) and the bellflower series (Metachlanu'detr). These agree in being made up of seed plants with the em})ryo having two cotyledons or dicotyled- onous.^ The i)arts of the flower are very generally in fours or fives, seldom in threes; the leaves are mostly netted- veined; and in the stem there may be distinguished a central core of pith surrounded by a ring or rings of wood anrl l)ark. See especially Figs. 232 and 233. Stems thus constructed ^ Pap'-pus > Gr. pappos, grandfather, applied to the thistledown in allusion to white hair. STC/. ^ Met'-a-chl;i-inyd"-e-ous < (ir. )neta, beyond. ' Di"cot-y-led'on-ous < Gr. d>.s, two; kotyledon, seed-leaf. THE GRASS FAMILY 387 are called exogenous ' or outside-growing, because new wood when formed is added on the outside of an okler ring. 143. The grass family (Graminae). Examples : oat (Hg. 1- 4, pages 12-14), rice (Figs. 5, 6, pages 16, 17), rye (Fig. 7, page 18), wheat (Figs. 8, 9, pages 19, 20), barleys (Figs. 10-12, pages 21, 22), maize (Figs. 13-15, pages 23, 24), sugar-cane (Fig. 114, page 106), broom-corn (Fig. 222, page 236), and bamboo (Fig. 224, page 239). Formulas of Zea, Saccharinum, Aiidropogon, Orj^za, Avena, Secale, Triticum, Hordeum, Bambusa, and Graminese are shown on pages 420-423. The grasses introduce us to a new sub-class, characterized partly, as we shall see, by having the leaf-veins running in a regular, more or less parallel system. Leaves with such a framework are said to be parallel-veined. Grass leaves always have the veins running lengthwise from base to tip. Other noteworthy features of grass leaves are that the base is wrapped about the stem so as to form a sheath the edges of which overlap as shown in Fig. 13; and the blades extend from only two sides of the stem, thus coming into two vertical ranks. Most grass stems are round and hollow like straws. Rarely, as in the stalk of maize, there is a solid cylinder of pith, through which run scattered bundles of firmer, more or less woody material, not forming true rings, but often so crowded toward the surface as to constitute a somewhat ])ark-like zone. From an erroneous idea that these scattered bundles originated near the center of the stem and were forced out- ward by new growth, all stems with scattered bundles were early described as "inside-growing" or endogenous - — a term still used conveniently, however, by way of contrast for stems of seed-plants of the non-exogenous type. The bracts and bractlets of grasses in general are com- paratively thin and stiff, like the husks or chaff of grain, and have received the special name of glumes.^ ^ Ex-og'en-ous < Gr. exo, outside; genes, producing. - En-dog'en-ous < Gr. endos, within. ' Glume < L. gluma, husk of corn. In our formulas the glumaceous character is denoted by the inverted exclamation mark as in Bj. 388 VARIOUS PLANT GROUPS The grain-like fruit of tyjiical grasses resembles an achene in being the product of a t^imple pistil with one ovule and in being dry and indehiscent. It differs mainly in having the seed-coat adherent to the pericarp. A fruit of this kind is distinguished as a caryopsis^ As shown in Fig. 9 the embryo is placed at one side of the all)umen. On the side toward the seed-food is a some- what shield-shaped organ, termed the scutelhmi,^ through which the germ absor])s its nutriment when sprouting. Mor- phologically the scutellum is regarded by most botanists as the cotyledon of the embryo, enlarged and otherwise modified for its peculiar function. Unlike the embryo of dicotyledon- ous plants, the emliryo of a grass, as of all the sub-class of seed-plants now to be studied, has but one cotyledon and is hence described as monocotyledonous.^ Grasses may be easily recognized as mostly herbs ivith hollow, cylindrical stems; parallel-veined, two-ranked sheathing leaves; flowers enclosed by glumaceous bracts; and fruit a cary op- sis. 144. The grass order (Graminales or Glumiflorae) com- prises grass-like plants ivith glumaceous bracts, a one-celled superior ovary, and a solitary ovule. The formula of Graminales is given on pages 422, 423. 145. The palm family (Palmaceae). Examples: coconut (Figs. 34-36, pages 46, 47), date (Figs. 108, 109, pages 100, 101), sago palms (Figs. 116 I-III, pages 109, 110), rat- tans (Figs. 223 I, II, pages 237, 238), and vegetable ivory (Figs. 266 I, II, pages 275, 276). The formulas of Phoenix, Cocos, Calamus, Metroxylon, Phj'^tele- phas, and Palmaceae on pages 422, 423. Although in our examples the leaves are all pinnate and compound, many m^embers of the family have simple palmate leaves, as for instance those from which the familiar palm- leaf fans are made. ' Car"y-op'sis < Gr. karyon, nut; opsis, resemblance. Its mor- phology is indicated in a formula b.y [CE/ < GIN. 2 Scu-tel'lum < L. a little shield. " Mo"no-cot"y-led'on-ous < Gr. monos, one. THE ARUM ORDER 389 The flowers of palms are borne on a fleshy rachis which is more or less branched and subtended by one or more large, thick bracts. Such a fleshy spike whether simple or branched is called a spadix,^ and the large bract subtending it a spathe."- Palms may be distinguished as iDoody plants, usually ivith columnar trunks; large, plume-like or fan-shaped leaves; flowers on a mostly branched spadixfornied within a spathe. 146. The palm order (Palmales or Principes) includes only the family of palms, which from their majestic appearance and high importance were well called by Linnieus the Princes of the Vegetable Kingdom. From other orders the ivoody trunks, large and often compound leaves, mostly branched spadix, conspicuous spathe, and the superior ovary with one or more cells, and one or more ovules, Avill generally afford sufficient marks of distinction. See formula of Palmales on pages 422, 423,. 147. The arum family (Araceae) is exemplified by Acorus (Fig. 167, page 174.) See formulas of Acorus and AraceiB on pages 422, 423. Although the members of this large family differ very much in general appearance and in many details of structure, our common sweet flag represents quite well their essential fea- tures. As in the palms, there is a spadix, although it is alwa3^s simple; and there is a spathe which, unlike that of the sweet flag, is generally highly colored. In our example, moreover, the spadix, while appearing as if lateral, is in reality terminal, having been pushed to one side by the peculiar elongated spathe which appears to continue the stem. The family may be defined as consisting of mostly perennial herbs, sometimes aromatic, often ill-smelling or acrid; with leaves of varied form., often netted-veined; and floivers in a sim- ple spadix, subtended by a more or less petaloid spathe. 148. The arum order (Arales or Spathiflorae) comprises ^ Spa'dix < Gr. spadix, a palm-branch. - Spathe < Gr. spathe, a broad flat blade or spatula. The exclama- tion marks used in the formulas after I and B indicate, as usual, the fleshy character, and the oblique line after B, its involucral nature. 390 VARIOUS PLANT GROUPS but one other family besides the al)ovc. Both are made up of herbs unth leaves of run'ed form, wmetimes rudimentary or absent; regular flowers in an unbranched spadix, with one or more spathes; and the superior ovary having one or more cells and one or more ovules. See formula of Arales on pages 422, 423. 149. The rush family (Juncaceae) is typified by the com- mon rush. (Fig. 221, page 234.) See formulas of Juncus and Juncacea; on pages 422, 423. At first sight the rushes appear somewhat similar to grasses, and indeed certain botanists have regarded them as belonging to the same order. The resemblance comes chiefly from the grass-like leaves of many species and the glumaceous charac- ter of the perianth. 1 The family may be defined as herbs with regular flowers having a glumaceous perianth, either six or three stamens, and a superior, compound ovary. 150. The lily family (Liliaceae). Examples: onion (Figs. 60, 61, pages 63, 64), asparagus (Fig. 62, pages 64, 65), Indian poke (Fig. 186, page 199), and lily-of-the-valley (Fig. 193, page 204). Formulas of Allium, Asparagus, Convallaria, Veratrum, and Liliacca' are given on pages 424, 425. One of the largest and most important, the lily family is generally easy of recognition as being composed mostly of herbs with regular flowers having a petaloid perianth, six stamens and a superior, compound ovary. 151. The iris family (Iridaceae) is represented by saffron (Fig. 168 II, page 176). See formulas of Crocus and Iridaceae on pages 424, 425. The Iridaceae are herbs having flowers like those of the lily family but-uuth only three stamens, and an inferior ovary. 152. The lily order (Liliales or Liliiflorae) comprises several families which are like the lily family in being mostly herbs with leaves of varied form; inflorescence never spadiceous ' Indicated in the formulas by the inverted exclamation mark. THE CASE-SEED CLASS 391 though sometimes spathaceous; flowers mostly regular; the ovary compound, superior or inferior; and seeds of moderate number and mostly medium size. See formula of Liliales on pages 424, 425. 153. The orchid family (Orchidaceae). Examples: vanilla (Fig. 148 1, page 149) and lady's-slippers (Figs. 212, 213, page 220). See formulas of Cj'pripedium, Vanilla, and Orchidaceie on pages 424, 425. Although in the flowers of this family we can recognize the fundamental type of structure exhibited by the liljMike families, it is here modified b}' many curious and elaborate complications. An orchid might be described as a lily with irregular perianth, one or two stamens inserted upon the st3de, the other four or five being suppressed or represented by staminodes, and with an inferior ovary so. twisted as to bring the flower upside down. A flower thus turned is said to be resupinate^ However obscure the morphology of special parts may sometimes appear, orchids may usually be recognized as perennial herbs, ivith irregular, resupinate, epigynous flowers, having a petaloid perianth, one or two stamens adhering to the style, and a capsular fruit unth exalbuminous seeds. 154. The orchid order (Orchidales or Microspermae) con- tains but one other family. This agrees with the orchids in comprising herbs similar to the epigynous families of the lily order but forming innumerable seeds of exceedingly small size. See the formula of Orchidales on pages 424, 425. 155. The monocotyl subclass (Monocotyledones) is made up of seed-plants having a monocotyledonous embryo, en- dogenous stem, and mostly parallel-veined leaves. Together with the dicotyl subclass they constitute 156. The case-seed class (Angiospermae) which includes all the flowering plants forming their seeds in a case or ovary ' Ro-su'pi-natc < L. re, back; supinari\ bend. The twist is indi- cated in a formula by o) placed after T. 392 VARIOUS PLANT GROUPS consisting of one or more carpels — or in other V\'ords — all that have an angiospermoua ^ gynoecium. Nearly all seed-plants belong to this class. 157. The pine family (Pinaceae). Examples: juniper (Fig. 154, page 158), pine (Fig. 258, page 269), larch (Fig. 259, page 271), spruce (Fig. 260, page 272), red cedar (Fig. 261, page 273), redwood (Fig. 262, page 273), and hemlock (Fig. 263, page 273). See formulas of Pinus, Larix, Picea, Tsuga, Sequoia, Juniperus, and Pinaceae on pages 424-427. A considerable variety of opinion obtains among botanists regarding the morphology of the floral parts of the pine family. According to one view the catkin-like clusters, or at least the seed-producing ones, are aments of very simple flowers; while according to the other view what appears to be a catkin or spike is a cluster of stamens or of carpels, and thus represents a many-stamened or many-carpelled flower. Without discussing the relative merits of these rival inter- pretations, w^e may provisionally adopt the latter as being the simpler view and as best serving our present purpose. ^ The carpels differ from those of the case-seed class (Angio- spermae) in being flattened structures; hence the ovules are exposed, or at least are not enclosed in an ovary. The gynoe- cium is therefore called "naked-seeded" or gymnosperfiwus.^ In fruit the gynoecium and elongated torus form a cone with more or less woody scales and axis; or, as in the junipers (Juniperus), these parts may become fleshy and consolidated into a berry-like fruit. The great majority of the pine famil.y are easily recognized as 7nore or less resinous, mostly evergreen trees, producing cones. 158. The yew family (Taxaceae) is exemplified by the yew (Fig. 204, page 213). See formulas of Taxus and Taxaceae on pages 426, 427. Simplification of floral parts here reaches an extreme. In ^ An"gi-o-spcrm'ous < Gr. aggion, a vessel ; sperma, seed. - In the formulas T\ indicates that the torus is here regarded as anal- ogous to an anient rachis. ^ Gym"no-sperm'ous < Gr. gyinnos, naked; sperma, seed. THE SEED-PLANT DIVISION 393 the yew (Taxus) not only is the perianth lacking and the androecium reduced to a few stamens, ))ut the gynoecium is only a solitary ovule borne directly upon the torus and with- out a carpel. This ovule ripens usually into a hard seed which is surrounded by a fleshy envelope formed by the upgrowth of a ring which at first encircles the base. Such an accessory seed-covering growing from below is called an aril.^ In other members of the family the staminate flowers are more cone-like, and there are a few with much reduced carpels each bearing a single ovule which may ripen into a drupaceous seed. The family consists of mostly evergreen, woody plants, with comparatively little resin or 7ione at all; having cones much reduced, or else the ovules solitary and without carpels; and the seed arillate or drupaceous. 159. The pine order (Coniferales or Coniferae) comprises only the two families given above. They are distinguished as woody plants, with branched stem; unhranched, usually narrow, leaves; and imperfect flowers which have no perianth, but are often catkin-like; and commonly produce cones. See formula of Coniferales on pages 426, 427. 160. The naked-seed class (GymnospermaB) , embraces onh^ a few orders besides the pine order, with only one or two families in each. They all agree in being seed-plants with gymnospermous gyna?cium, and are for the most part destitute of perianth. 161. The seed-plant division (Spermatophyta) is coexten- sive with that branch of the Vegetable Kingdom commonly known as Phanerogamia, phenogams, or flowering plants, because characterized by the production of flowers contain- ing at least either pollen-sacs or ovules. Since the produc- tion of seed is the function of these parts, and since no other plants produce true seeds containing an embryo, it is equally appropriate to speak of them as seed-plants, seedworts, or spermatophy tes . The system of classification (although not always the sequence of groups) adopted in the foregoing pages is sub- ^ Ar'il<. L. arillus, a dried grape (for no obvious reason). 394 VARIOUS PLANT GROUPS stantially that of Engler and Prantl whose great work on the natural famiUes of plants is now most generally followed, at least, with regard to phenogams. In this classification there are recognized among seed-plants about fifty orders and two hundred and eighty families. The eighteen orders, thirtj'-two families, and about a hundred genera of seed-plants included in this chapter are represented by formulas on pages 404-427 in order that the student may readily compare the more important structural characters of one group with those of another, and so gain a better grasp of the abstract ideas underlying a natural classification. Taken in connection with the accounts of the various groups given in the sections referred to by number before each formula, and with reference to the figures indicated in each section, the formulas will afford a most profitable means of reviewing the many details already studied, and will re- veal some of their wider relations. 162. The vegetable kingdom (Vegetabilia) which includes all plants is regarded most conveniently as consisting of four main divisions assumed to be equal in rank.' The highest division, that of seedworts or spermatophytes, includes most of the forms we have been studying. These agree not only in producing seeds but also in having true roots, stems, and mostly green leaves, all traversed by more or less woody strands, known as fibrovascular bundles, which form a framework or skeleton, and conduct nutrient juices to every part. True roots, stems, and green leaves, all ])rovided with fibrovascular bundles, occur also in such plants as the male- fern (Aspidium, page 179) and the club-moss (Lycopodium, page 174); but these plants propagate by spores developed in minute spore-cases, and never produce seeds. Plants thus characterized form the pteridophyte or fernwort division. (Pteridophyfa). Next to these come such plants as peat moss (Sphagnum, page 242) which propagate by spores similar to those of fern- worts but contained in more or less urn-like cases commonly nuu'h larger than fernwort spore-cases, and usually borne on 1 This view differs somewhat from that of Engler and Prantl, but best suits our purpose as being the one most widely adoi)ted at the present day. THE VEGETABLE KINGDOM 395 conspicuous stalks; hut these plants have no true roots, stems, or leaves witli Hhi'ovascular bundles, although often possessing very sinij)Iy constructed parts reseml)ling small roots, stems, and leaves. Humble green plants of this descrip- tion make up the brj'ophyte or mosswort division {Bryo- phijta). Finally come such comparatively simple forms as the so- called Iceland moss (Cetraria, page 169), the field mushroom (Agaricus, page 113), and the carrageen (Chondrus, page 112) which, although commonly propagating by spores that are sometimes in cases, have the cases either stalkless or other- wise plainly different from those of mossworts. True roots, stems, leaves, and fibrovascular bundles are never present, although the plant-l)ody may be so lobed as to resemble somewhat that of higher plants. Hence these lowly organized plants form what is known as the thallophyte or lobewort division (Thallophytn). Our three examples of the lobewort division each represent one of its three sul^divisions. These may usually be dis- tinguished by their different modes of life. The Iceland moss is an air-plant merely resting upon barren soil without having any means of drawing much nutriment from it, and is con- sequently dependent upon what it can get from the air. This mode of life is made possible by the somewhat spongy nature of the plant-body in which are embedded minute containers of chlorophyll that may become apparent upon wetting. Plants like this so-called "moss" which thrive in barren places such as tlie surface of rocks, bark, dead wood, and sandy soil are of the lichen subdivision (Lichenes). The field mushroom differs from all lichens in being entirely destitute of chlorophyll because it feeds directly upon animal or vege- talile manure in the soil. Lobeworts which can thus dispense with chlorophyll by feeding upon animals or plants or their decaying remains are of the mushroom or fungus subdivision (Fungi). Aquatic lobeworts, whether of fresh or salt water, which like carrageen contain chlorophyll (sometimes more or less obscured by red, brown, or l)lue coloring matters) form the seaweed or alga subdivision (Algre). The following synopses show in tabular view the divisions 396 VARIOUS PLANT GROUPS III li |o|. il ^p li "^ § H rj b in ° ^ =^ £ O rt S ^ > oil ss ^^>.^x ^« >..=!« ^d^ H^ '^ ^ fe'>>'^o^-^| m CO ^ < ? J ?i^ CO C> 3 2 0 fi! « ^a"=§ 1^? ^§1 1q g ^-a= >s s'^a III 2?^ § l§a^QS 1^^ ^.ss III ^ OS*" '-''a— fl dj -« -^ > ?? H ■r rf a^ » c A f^ S"" J '-' S S £ f^ S_ ispti ^ ^=^ '" - ' -^ C s B3 t^ 3 2 ^ rt^ u c-S^K^ S PL, VARIOUS PLANT GROUPS 397 o i o 05 '-*^ III c: - o c ^ 1 ^"2 2 1^ ^ hJ CO 5 1' f S| PI e S 1 . g t s Si a g s s II s ir e-2 r^ ■^ vi v; a. -^ ■^ ^ Ci;>~)'^>^ a?;; :&LHO.Maa3g isrcHadSoxKiQ siODoxojv; 398 VARIOUS PLANT GROUPS a, s CQ ^ r-i Ol s s^ 2-^'-3 ;^ . cab. r.'^t^ &:, u. >-- Sl . b,'^ -^15 5 c *-c -VJ S"s« M fe 03 aa ^^fe: ^ ^ (>in ■*iO-^ t>; Ol i^iOi INM(N (N d o 2 a MM a « 2' s tj P C rS c3jn B .. o a ;— m -< W ? a g 73 & c: o O) ^ s fc a i « c ?; ?=-« o c o s-5 ^ -S O w^_- .- d ?i '2 S -s §? ipi C t- fe-g'S 3-n c-=0 S t. ::-o t ?^ ?t a;a3 ^^O 1^ fc.'^ ^■-i, OQ5 ^ K fe.fe.-x; S;r •-CC 0-3 Q. oj** 4) O P, DO fciQ o 0) a 6 o dOO SiOOIQ VARIOUS PLANT GROUPS 399 H3ACKI 400 VARIOUS PLANT GROUP? E-.;^^;^ 1^1 ■*^ O c ^ T! _:_:=:33 u £ — £— £ ^ "- S fe 8 <- s o 3SB C s; O t^t^t^ i^t^t>. :- 4> 4> .5s a S -o S — — Ed^> -old d panuijuoi — sxooiQ aa.ttO'x VARIOUS PLANT GROUPS 401 «^ a a ^ S^ 1 & &;&: C b) M 8 1 !«. !* °>c;d O Ci O-H (N t>. 00 00 00 '*•!*;'*'■« "^ e) Q ^ s a I. CQU -S 2 2 S 00 00 00 00 r^ 00 o o —> 00 OOOO OJ 03 3S = 05 ^ XI i ^1- San Mo :8iooiQ Haaoig 402 VARIOUS PLANT GROUPS and subdivisions of the vcgeta])lo kingdom, together with one hundred of the more important famihes of seedworts, and the orders and higher groups to which they belong. The characters given to distinguish them must be understood as l)eing merely those which prevail throughout the group to which they refer, and not as being without possible excep- tions besides thos(> noted. The numbers in parenthesis refer to pages where further information regarding the families, or illustrated examples of them, may be found. These synopses show the place in a modern classification of every plant we have studied in the foregoing chapters. Familiarity with the distinctions given, obtained by practical use of tiie synopses, should enable students to tell at sight, for a large majority of the plants they may see growing wild or in culti- vation, the famil}' to which each belongs. The student who has learned to know what is typical of the comparatively few orders and families which we have been examining, will be able to tell at sight the famil}^ or order in which, or near which, to classify more than half of the flowering plants he is likely to meet; provided, of course, he has observed carefully their structural features. This knowledge, and the acquaintance he has already gained with the most important descriptive terms, will facilitate his use of systematic works in which these and other families are described in more detail. However far he pursues this line of study — as fascinating as it is exhaustless — the student will continualh' encounter plants whicli must be viewed as intermediate links connecting different groups, or as exceptions which make definite limi- tations practically impossible. These connecting links and exceptional cases seem to defy classification in any consistent arrangement, and have caused endless trouble to botanists in their attempts to construct a natural system. But at the same time it has happened that as botanists have come to study the significance of these exceptions they have found them revealing some verj'^ deep truths which have led to more and more satisfactory systems of classification. It behooves us therefore to examine the main beliefs which have been held in regard to the meaning of these connecting VARIOUS PLANT GROUPS 403 links between species, genera, families, and wider groups. As will be observed, the very word "family" implies an idea of kinship. Here, indeed, is a key which if it fits, may unlock for us secrets of great importance. To try this key is the purpose of the chapters which follow. FORMULAS OF A Caltha(101--105) 01 L'/i* ri+Sbi,o S"4+ FA 00 Helleborus Qi Li/i*,L ri+sbi± S"5 F5+ FAoo Nigella © y/i^L riSb/5.0 S"5 F5+ FAco Aquilegia 21 LVi + L^+r'/s S"5 F5 FAoo F 5X5 Aconitum 21 LVi* I" S S"f Fo?3 FAoo Actsea 21 L\/itL2+ I" 8 ■ S"3-5 F4+ FAcx. Anemone 21 L\'i*t,L ri+sB,b/2,3 S"4 FO-ooFA 00 Clematis 2l,br^ L2/2+t,L ri+,i's,Scf9 S"4+ FO-oo FAoo,0 Ranunculus O L\li* 11+ a S"5± F5+ FAoo ^lyosurus © LV'i ria S"5+ F5± FA 5 + Pa>onia ±,2l LVitLi-3 risbl+ S"5+ P"5+ FAoo Ranunculace.e O,:^ U/i- Ig S"5± PO-cc FO-oo FAoo, oc SEED-PLANTS 405 marsh-marigold CE5=t E& T^ C/c:5± 7^00 G-N Christmas rose CEo,) ES> T^ 0-5c±,) ^00 G-N fennel-flower CE5±) E^ T^ Ci^o^) ffoo G-N columbine CE5 E3> T^ Cko Eo= G-N monkshood CE3-5 E- T^ Ci^3-5 Eoo G-N baneberry CEl E» T^ Ci 00 El G-N star-anise • CEoo Ei T^ Ci coo El G-N tulip-tree CEcx) Ei T^ Q T^] bellflower C^E 3-5) E % T^l Indian tobacco, etc. CE2) ES rca < Eo= G- rc!i< ^oo G- Tca < ^00 G- TC.'i < E G- TC!° Ea, G- TC!i< Eoo G- TCi° Eco G-X TCI 1 Eo= G-N 420 FORMULAS OF Campaxulace^ 0,b LVit I~8 S"5,f) P"5,),5) FA 5,)) Helianthus (139) O LViZ/^t !'•• s6B/oobS"2+ F'5),5) FA5)] Lactuca O LVi^ Ii'"sB/oc S"^ooP"5) FA 5)] Artemesia O LVitL I'i'-- s 9 B/oc SO P"5),5) FAo)] COMPOSIT.E O LVi~ ri'"' S ~B/cc +,bS"5^cc =tP"5),5)~ FA 5)] CAMPANULALES (140) I 8 0^96 S~ P5,5),5),|) FA 5,),),] ® LVi % LVi ® LVi ® LVi ® LVi f? LVx ® LVi I ® LV i'-"9-o^Bbi SPO i ' : s Bbi i ' : s Bbi i ' : s Bbi SPO i': S d^Bbi SPO SPO i': SSBbi SPO SPO i ' : S 6 Bbi SP 0 i': S,6Bbi SPO r i ' : S cf 9 Bbi SP 0 Zca (143) FA 3 Saccharum FA 3 Andropogon FA 1-3 FA 6 FA 3 FA 3 Orj'za Aveua Sccale Triticum FA 3 Hordeum FA 3 Bambusa FA 6 = SEED -PLANTS 421 BELLFLOWER FAMILY CE2+) E^ T^] TCi Eca G-N sunflower, etc. CE2() Ei T.,] TCl< El G- lettuce CEO Ei T.] TSCi < El G- wormwood CE2() Ei T^] TCi< El G- SUNFLOWER 1 FAMILY CE2() ■ Ei T^] STCi< El G- BELLFLOWER ORDER CE2-5),0 T^] maize CEl Ei T^ Bb [CEJ< sugar-cane CEl Ei TV. [CEi< broom-corn, CEl etc. Ei T^ B [CEi< rice CEl Ei T^ B [CEi< oat CEl Ei T^ B [CEi < rj^e CEl Ei T^ [CEi< wheat CEl Ei T^ [CEK barley CEl Ei T^ b {CEi< bamboo CEl Ei T^ [CEK G/N G/N G/N G/N G/N G/N G/N G/N G/N 422 FORMULAS OF GrAMINEjE O LVi I-'i':s~Bbi SPO FA3± GRAMINALES (144) I~Bi SPO~ FA3 + Phoenix (14")) 3 LVi^L Ili^cf :9B!/ S"3 P" 3 FA 3x3 Cocos b Li/i^L I!i:c^-9B!; S"3 P" 3 FA3x3 Calamus Li/itL I!i:d^:-9B!/S"3 P"3 FA 3x3] ^Metroxylon 3 V,\tL Ili^cf 9 SB!/S"3,1 P"3,) FA3x3]" Phytelephas 3 LVitL I!a^:9B!/cc S" 3 P"5-10 FA co Palmace.e 3 Li/i,*tL I!,i:c^ 9B!/ S"3 P"3+ FA3x3 I!B!/ S"3 P" PALMALES (146) '3 FA 3x3 •21 ^\'i I! gB!/ SP" 3x3 Acorus (147) FA 3x3 O LVi I!s ~ B!/ SP" '3x3~ Arace.e FA3x3~ I!B!/ SP" '3X3~ ARALES (148) FA3x3~ % LVi 1-9 SP" i 3X3 Juncus (149) FA 3X3, 3 Qi L'/i 1-8 SP" i 3x3 JUXCACE.-E FA 3x3, 3 GRASS FAMILY CEl Ei GRASS ORDER CE 1,2-30 Ei SEED-PLANTS T^ [CEl< T^ 423 GJN date CE3 Ei T, coconut CE3() Ei T rattan CE3) Ei T sago CE3() t:i,3 T vegetable ivory CE5±) ^ Ei PALM FAMILY CE 3 +,),() Ei PALM ORDER CE3,),() Ei + T. C/7< El Cii!!< El C.'IK E3 C!ii< E3 C'xif? X FA§ Vanilla 21- LVi ra SP" !x 1 FAfxf!! Orchidace.e 21 LVi rs SP"!xi,f? X FA^xf ?, FAS ORCHIDALES (154) I' SP"3x3,iX h FA 6-1 Pinus (157) 3 L/Vi,/i-5 Icr-9 SPO FA 00 Larix 3 LVi,/c^ Id^-9 SPO FA CO Picea 3 LVi 1(^-9 SPO FA 00 SEED-PLANTS 425 onion, etc. CE3) Ei + T,^ CiA. Eoc G-N asparagus CE3) E^ Tr^ C!< E, Caltha most nearh^ resembles the ancestor of the family. According to this view the story of the family's evolution would be somewhat as follows. Among the descendants of Caltha- like moisture-loving plants which grew in a remote geologic age, some retained for innumerable generations the characteristics which fitted them for living under the comparatively uniform con- ditions afforded bj'' protected moist situations, and are represented to-day by our marsh-marigolds. In these have survived a most primitive type of flower, h3'pogynous, with many-ovuled, distinct 438 KINSHIP AND ADAPTATION carpels, numerous stamens of ordinary form, and a regular perianth of almost leaf -like sepals; and a very simple form of palmate leaf and herbaceous stem. Certain other descendants of the primitive stock showed in very early times a modification of the torus and perianth (resulting in pcrigynous flowers with the perianth differ- entiated into a well-defined calyx and corolla), also an advance in complexity of leaf-form, and more or less woodiness of stem. The plants of this branch were thus able to thrive imder the more exact- ing conditions of open fields, and have become the highly developed sturdy peonies of to-day. Very early in the development of what we may call the hj^pogynous branch of the family, there appeared some more or less Caltha-like forms, in "which the carpels did not open at maturity, but separated like seeds from the parent plant. This change of habit made it unnecessary for more than one seed to mature in each carpel, so the result was an achenial instead of a follicular fruit. Those descendants which retained rudiments of several ovules became in time either forms of Anemone or of Clem- atis according as they developed the peculiarities of this or that genus; while similarly those in which the reduction to one ovule was complete, gave rise to such plants as buttercups and mouse-tails. In much the same way we find those descendants which comjirise the more primitive subbranch with its many-seeded carpels becom- ing differentiated into forms retaining the original follicular fruit, and forms in which the fruit is indehiscent and fleshj^, as in Aetata. Along the lines with follicular fruit the appearance of forms with certain of the stamens changed into more or less conspicuous nec- taries give rise to a departure from the Caltha-like forms, which in turn became differentiated into those in which the corolla remained regular and those in which more or less irregularity v/as shown, as in monkshood. Finallj^, the regular-flowered forms with staminodes developed such peculiarities as the spurs of Aquilegia, and the curious follicular capsule of Nigella, bj' which the modern genera of this subgroup are now distinguished. ^ 1 It might fairly be asked whether entirely different lines of descent from those here given would not as well explain the modern forms upon which our reasonings have been based. Undoubtedly this is true. Thus, instead of supposing the progenitor of the family to have been an herb like tlie marsh-marigold we might perhaps with more probability assume it to have been a shrub or tree resembling a woody peony or a magnolia; for in other families there is much evidence in favor of the view that herbaceous seed-plants have had woody ancestors. But in this family we have no direct proof that its earliest members were wood}', and for us to make the assumption would complicate our reasoning without rendering any clearer the general principle we are trying to make plain. Let the student, therefore, take our crowfoot family tree simplj' as rep- resenting one out of many possible ways of accounting for the facts at hand, and as liable to modification whenever new light appears on the problem. It is merely intended to illustrate the kind of reasoning that biologists emjiloy in the absence of evidence from fossil r(>mains, and DOCTRINE OF ORGANIC EVOLUTION 439 If we trace the evolution of a given form backward to its beginning we come to more and more primitive conditions. Mouse-tails, for example, we should derive from ancestors re- sembling buttercups in having a shorter torus, more stamens, spurless staminodes, and broader leaves. It seems reasonable to suppose that these mouse-tail-buttercups left no unmodified descendants, and so were not exactly like any living form of buttercup, although we might fairly presume that they showed more of the relatively primitive buttercup structure than of the peculiar mouse-tail features. These buttercup-like ancestors would be traced back to progenitors more nearly resembling anemonies in which rudimentary ovules still bore witness to a previous many-ovuled stage, when also certain of the outer stamens were showing only rudimentary anthers and were secreting nectar on broadened filaments. The step from this form, from which both mouse-tails and anem- onies descended, to the marsh-marigold-like ancestors of the family, requires us to imagine little more than a previous full development of the ovules and anthers which later became reduced, and a more ordinary form of filaments and carpels. In the above examples of the way an evolutionist conceives the changes in a group to have progressed, innumerable details of the process have necessarily been omitted for the sake of simplicity. jNIany branches would have to be inter- polated if all living genera of the family were to be repre- sented, and there is no knowing how many dead branches should be shown to make the family tree complete. It must, of course, be frankh^ admitted that the conclusions are largely guesswork supported only by circumstantial evidence, for no remains of the very perishable ancestral forms of the crowfoot family have come to light. Our examples, however, are typical of evolutionary schemes in general, and so may help our understanding of the theory' of evolution. One prevalent misconception which it should correct is the notion that forms now living are supposed to have been derived from ancestors just like other recent forms. On the contrary, the kind of conclusions they reach by such means. That such conclu- sions are at best far from satisfactory goes without saying; but herein lies a challenge to do better, and a spur to further study. 440 KINSHIP AND ADAPTATION evolutionists believe that more or less modification is the rule among all the descendants of a given form, and that only rarely has it happened that ancestral forms have persisted for ages unchanged. Thus, in regard to the last examples, the most we should be willing to say is that mouse-tails were probably derived from plants something like the more primi- tive forms of recent buttercups, such as the ditch crowfoot (Fig. 209) ; that these ancestral crowfoots came from plants something like our marsh-marigold; and so on. It is thought that single traits or a few traits in combination, are more apt to survive through long periods than the many jDeculiari- ties characterizing a complex structure. Closely connected with the erroneous view above men- tioned is the notion that all the modern representatives of a group can be arranged in a single series beginning with the most primitive, and passing on to the most highly evolved through survivals of the intermediate stages or "connecting links." From what has been said it will be obvious that such an arrangement would be possible only on condition that all the forms which had ever appeared were actually repre- sented by living descendants and that modification had occurred only in one direction. As a matter of fact, gaps, often great, between related forms are continually met with. Indeed, if the "connecting links" of the past, represented by the dead branches of our tree, had not disappeared there would be no possibilit.y of classifying living forms into groups and subgroups, for there could be no limits to any group. Sometimes within a group it is as if Nature had as yet done little or no pruning, and the result is most bewildering to those who attempt a classification of the forms. No two students of the group are likely to agree as to where lines of demarca- tion should be drawn. Such a group is that of the roses previously mentioned. But even here, for all the embarrass- ing wealth of connecting links, it is quite impossible to ar- range the forms in a single series. There are many diverging series which branch again and again. Their relationships as inferred from their degrees of likeness can best be expressed by a branching system, and while of course the systematist must deal with his groups one after another in simple sequence, ACQUIRED ADAPTATIONS 441 he cannot make such a sequence adequately express his idea of their kinship. If we are warranted in supposing that all members of the crowfoot family are the descendants of plants like our marsh- marigold we may assume with scarcely less probability that plants closely similar to these primitive marsh-marigolds were the ancestors of all of the crowfoot order, and indeed that from plants having very much the same primitive cliaracteristics came, in the course of geological ages, all of the dicotyls and perhaps all the monocot3ds as well. Our mental images of ancestral forms are necessarily dim in pro- portion to the remoteness of the form conceived, and are likely to change as we receive new light. Yet these mental diagrams of things no longer to be seen help our seeing of the things about us. From the evolutionary point of view all life takes on a new significance. The possibility of gaining some glimpses of how the living world came to be as it is, makes all life more deeply interesting. Details of structure or behavior in a humble plant may lead us to some of the greatest truths of life. 166. Acquired adaptations. The belief that all existing organisms are the more or less modified descendants of rel- atively primitive forms, is now as generally held bj^ naturalists as is the belief in universal gravitation among astronomers. Yet astronomers are still striving to understand how it is that the force of gravity can act as it does; likewise naturalists are still debating the fundamental question as to how in- herited modifications have arisen. That somehow plants and animals have evolved is now taken for granted; but there are wide chfferences of opinion as to the way in which the changes have been wrought. In these few pages w^e can glance only briefly at the lead- ing views now held regarding the origin of species. Each theory aims to account for the appearance of those peculiari- ties of structure or behavior which distinguish one group from another; as for instance the climbing habit of clematis and the long, mostly hairy-tailed fruit which is found no- where else in the family except with certain anemonies in- habiting wind-swept fields. Peculiarities of this sort are 442 KINSHIP AND ADAPTATION often connected in some helpful way with the life of the in- dividual— hairy appendages insuring to achenia widespread dissemination by wind, and the power to climb facilitating economically the quick exposure of green parts to sunlight. In such ways an organism, as we have seen, is adjusted, often marvelously well, to its environment; and we call the adjustments which promote its welfare adaptations. It is with questions of the origin and inheritance of adaptations that the debates of evolutionists are mainl}^ concerned. We must, therefore, at the outset examine carefulh' just what is meant by an adaptation. Every individual plant or animal is found to have the power of modifying its form or behavior in response to out- side influences, and such modification is often beneficial. Indeed we need not distinguish here between form and behavior, for even structure is but the result of growing in certain ways, and growth is merely a slow kind of behavior. So we may say that each living thing, in so far as it is alive, has a certain limited power of adaptation through direct response to environing influences. As a seed sprouts, its little root turns toward the place of greatest moisture, while the young leaves are directed toward the light, and if the illumination be feeble the stem helps the leaves by elongating more than it would if the light were stronger. A tree exposed to strong winds of one prevailing direction takes on a one- sided form thereby reducing the strain. Herbs which in rich moist soil produce tall stems and ample foliage before they flower, will on a sandy roadside bloom as soon as they have made a few small crowded leaves and are only a few inches high, thus, doing the best they can under adverse conditions. Dandelions grown on a mountain side look very different from those grown in the lowlands (Fig. 301), and the peculiarities of each seem to fit in especially well with the contrasting conditions. Such cases of advantageous adjust- ment made during the life of an organism may be termed individual adaptations. From these we must distinguish characteristic adaptations, or advantageous peculiarities be- longing to whole groups. Of such adaptations the charac- teristics of clematis above referred to may serve as examples; ACQUIRED ADAPTATIONS 443 or we might take a mountain species of buttercup (Fig. 302) which differs from near relatives of the lowlands in having a stunted, compact form well suited to alpine conditions and a rosette of leaves somewhat resembling those of our moun- FiG. 301. — Common Dandelion {Taraxicum officinale. Sunflower Family, Compositw). P, plant as it grows in the lowlands, reduced in size. ISI, plant as it grows at high altitudes, reduced in the same proportion as P. M', the same plant as M less reduced. (Bonnier.) — Native home, Europe; very common as a weed in America. tain form of dandelion. A peculiarity supposed to have arisen in response to some direct influence of the environ- ment is said to be acquired. If it be characteristic of a group it is called an acquired character, while in so far as it serves to fit the organism for the special conditions of its life it is an acc^uired adaptation. 444 KINSHIP AND ADAPTATION It has been thought l)y man}' naturahsts that the differ- ences among plants and animals may best be accounted for as peculiarities which have arisen in individual acquire- ments, these having become hereditary and thus characteris- tic after many generations of similar response to a similar enviromnent. Suppose, by way of example, that some of the seedlings from primitive marsh-marigolds grew in a rather dry locality and were more or less shaded by over- growth. They might be expected to respond to the lessened light by elongation of the internodes and leaf-stalks, while a Fig. 302. — Pigmy Buttercup (Rnnu?iculus pygmwus, Crowfoot Family, RanunculacecE) . Plant. Flower. Fruit. (Britton and Brown.) — Perennial (?) herb 5-12 cm. tall; flowers yellow; fruit dry. Native home; northern America and Eurasia. finger-like lobing of the blades through increased growth along the ribs and scant growth of the pulp between the stem would be fortunate as enabling the leaves to catch more of what little light there was. But the less favorable conditions for food-making would render it impossible for them to form and feed as many seeds as the marsh plants had done; hence some of the later-formed ovules would be more or less starved. From the good seeds formed by these pioneer plants and scattered in the vicinity, a second generation would arise, the individuals of which would respond similarly to the same trj'ing conditions. Innumerable generations might follow, ACQUIRED ADAPTATIONS 445 similarly responding, and if each generation were influenced ever so little by the responses of the generations before, that is to say, if the acquired peculiarities were inherited to any extent, the foundations laid by the pioneers would be built upon by their descendants. As a result we should have in successive generations the stems growing longer, and the leaves more branched and finally becoming com- pound. An increased sensitiveness to light might be accom- panied by greater sensitiveness to contact and this might lead to a coiling of the leaf-stalks around neighboring twigs, thus establishing the habit of climbing by means of which better exposure to light would be most economically secured through utilizing for support the very bushes which had made the shade. As a consequence of the starving out of the upper ovules there would result finally a fruit the upper part of which had become a mere tail-like projection sur- mounting a one-sided indehiscent base. A general hairiness which had been developed in all the exposed parts of the plant in response to the dryness of its new environment might especially affect the fruit as being now especially ex- posed, and might lead even to an elongation of the tail which would thereby become well adapted for enabling the wind to carry the precious seed high over surrounding shrubbery. In some such way as this it is conceivable that the characters of a clematis may have evolved. The first naturalist to suggest that organisms had evolved through the accumulation of acquired characters was Jean Baptiste Lamarck, of France, who flourished in the early part of the nineteenth century. His doctrine is called La- marckism, or as modified by his more recent followers, N'eo- Lamarckism. Lamarckians have advanced much evidence to show that acquired characters are often adaptive and may be inherited; but while most naturalists might concede the possibility of such characters being now and then adaptive, the great majority of evolutionists have remained uncon- vinced that acquired characters are ever fixed by inheritance. So far as we know, acquired characters do not long survive the conditions under which they arise. Cultivated plants escaped from cultivation soon become, as we have seen, 446 KINSHIP AND ADAPTATION indistinguishable from wild plants of the same species. But might not very long subjection to changed conditions finallj' fix an acquired character? Possibly, and it should be said that the botanical evidence is perhaps more favorable to this view than the zoological; but if the facts can be explained without relying upon suppositions hardh' possible to verify, we may build upon a safer foundation. 167. Selected adaptations. Dissatisfaction with La- marck's explanation of modification through acquirement, deterred most of his contemporaries from accepting the theory of evolution, and it was not until Charles Darwin and Alfred Russel Wallace offered an explanation based upon acknowl- edged facts that evolutionism was welcomed at all widely by scientific thinkers. The new doctrine is generally known as Darwinism, because Darwin's contributions in support of it were most extensive and important, although both Darwin and "Wallace, working quite independently, came to sub- stantiall}' the same conclusions, and announced them at the same meeting of the Linnsean Society of London in 1858. Darwin felt that the problem of how one species changes into another might best be attacked by studying the modi- fications which plants and animals undergo when domesti- cated. We have already seen (page 126) how much has been accomplished with cultivated plants by artificial selection, — farmers taking their seed from those individuals which please them best and continuing to pick out for propagation year after year the plants which show most fully those most de- sirable features. Here it would seem as if hereditary pecul- iarities were surely depended upon, and that the most strik- ing departures from an original form represented the sum of many small differences in one direction accumulated through successive generations b}' inheritance. Darwin reasoned that if it could be shown that plants and animals in nature were continually subjected to agencies which favored the propagation of individuals possessed of slight hereditary peculiarities contributing to their welfare, the most perfect adaptations would be accounted for and the origin of species scientifically explained. What natural agencies can be supposed to exert a selective SELECTED ADAPTATIONS 447 power at all comparable to man's infiucnce in developing artificial varieties? In the first place Darwin pointed to the fact that every kind of plant or animal produces more off- spring than can possibly come to maturity; for if none died without issue, the progeny of one individual or pair of in- dividuals would shortly cover the whole earth. Thus fifty dandelion plants from one, each bearing fifty-fold, and so on for nine generations, would make more than enough dande- lions to occup3^ every foot of dry land on the globe. In- numerable individuals of innumerable kinds are continually producing offspring in large numbers. Since many more are produced than can mature it appears that a competitive struggle for life must be going on throughout the living world; and, he argued, so intense is this struggle that if some indi- viduals had an adaptational peculiarity which gave them even a slight advantage over their rivals, such favored in- dividuals would be the ones to survive and leave offspring. Some of their offspring would be sure (judging from breeders' experience) to inherit the same peculiarity, and these favored offspring would in turn transmit it more or less enhanced to certain of their descendants, and so on along lines of fa- vored individuals in which the peculiarity in question would become more and more pronounced. This improvement would continue up to the point of adapting the organism as perfectly as possible to its environment. In this way a fa- vored race might become a new species through survival of the individuals best fitted to a slowly changing or slightly changed environment. The natural agencies which favor the survival of certain races in the struggle for existence Darwin compared in a metaphorical way to the human agencies which control the production of cultivated varieties. Both Man and Nature, he argued, act by selecting through successive generations certain peculiarities. Man chooses to encourage what pleases him. His method is Artificial Selection. Nature encourages only those peculiarities which best fit the organism to its environment ; her way Darwin called Natural Selection. The phrase has been often misunderstood through failing to take it merely as a symbol of the way certain natural forces act. 448 KINSHIP AND ADAPTATION Darwin defined natural selection as meaning "the preserva- tion of favored races in the struggle for existence." He accepted Herbert Spencer's phrase, "survival of the fittest" as a good equivalent. The theory of natural selection assumes, then, a struggle for existence among contemporary individuals in a given environment — a struggle resulting from vastly more of each kind being produced than can possibly survive, and so in- tense that even a slightly advantageous peculiarity may be enough to secure for its possessor both life and offspring. Such favoring peculiarities, according to the theory, are to be found in the small differences observable among indi- viduals of the same kind living in the same environment. Hence we need not suppose them to be acquired, and we ma}^ safely regard them as hereditary because experience shows that peculiarities of this sort are regularly inherited. Since these slight departures from the parent form take various directions under the same circumstances, they are termed fluctuating variations, in distinction from definite variations, which are all in the same direction, as must be the case with those due to the same influence — like a direct effect of the environment — acting upon similarly constituted organisms, Darwin did not pretend to explain the origin of fluctuating variations further than to regard them as con- stitutional peculiarities resulting from the interplay of in- ternal forces. These he saw might be so delicately balanced as to be readily disturbed by change of environment, and he recognized that a change of conditions commonly induces variability, and so gives a wider range of differences for selec- tion to work upon, as when a horticulturist desiring to develop a new variety subjects his seedlings to unaccustomed condi- tions. But in so far as the variations are in different direc- tions, they must be regarded as induced by the change rather than produced directly by it, and so may be spontaneous rather than acquired. Darwin's theory carried to its extreme by his modern followers, known as Neo-Darwinians, denies that acquired peculiarities are ever fixed by inheritance. Only what was inborn in the parent, they say, can be transmitted to the SELECTED ADAPTATIONS 449 offspring, and the more often such pecuHarities have appeared in the hne of ancestry the surer they are to reappear in all the descendants. Neo-Darwinism is thus in sharpest contrast with Neo-Lamarckism. The thoroughgoing Darwinian of to-day rejects all direct influence of the environment as a factor in organic evolution. Assume spontaneous variations, he would say, and let some of them be in adaptational direc- tions, then in the struggle for existence which is always going on, the life and death of rivals will turn upon which has in- herited the better equipment, and upon this will also depend the chance of transmitting to offspring the qualities which saved the parent's life. Everj^ gain in efficiency of adaptation will thus be preserved and successive gains accumulated till highest efficiency is reached, and when the most perfect adaptation has been secured it will be maintained indefinitely so long as the environment remains essentially unchanged. Since there are often different ways of attaining the same end, and so fitting different individuals successfully into the same environment, and since also there are different environ- ments to which a variable species ma}^ accommodate itself, such a species may give rise to several species in the course of many generations. If the intermediate forms or " connect- ing links" from being less perfectly adapted than the extreme forms should eventually succumb in the struggle, and so become extinct branches of the genealogical tree, gaps would appear between the surviving forms permitting us to define them as distinct species. A longer continuation of the same process would result in the differentiation of genera, fanlilies, and higher groupg. Let us see hoAv the theory of natural selection would apply to our supposed evolution of clematis. Imagine many thousand primitive marsh-marigold individuals inhabiting moist localities surrounded by drier spaces. These plants would be sure to vary somewhat in their ability to withstand occasional dry seasons. Among the millions of seeds pro- duced by the tougher individuals a good share would surely be scattered along the edge of the drier spaces where there would yet be enough moisture for them to sprout. Those of the seedlings which had come from the toughest parents and 450 KINSHIP AND ADAPTATION had inherited most fully their touglmess would gain a foot- hold where the less favored of their fellows could not survive, and, since the adversities of the new environment would try them more and more as they grew older, only the very tough- est of them could produce seed. Still it might fairly be sup- posed that a few, at least, would do so. Most of these seeds would fall on the drier soil, the seedlings therefore would similarly compete, and the winners be selected from among the very toughest. Such rigorous selection might be expected to insure a progressive toughening in successive generations of drought-defying plants, and a continuation of the process might be expected to result in a gradual invasion of the drier spaces by much toughened descendants of the moisture- loving form. Once accustomed to the drier soil they would have become less fitted for a wet locality and their progenj^ would consequently be excluded from the old home. During the gradual adaptation of the new form to its drier environ- ment, the individuals might acquire more or less adaptative peculiarities and so far as the toughness was not impaired thereby, these new features would be permitted by natural selection and might appear in successive generations just as if they were inherited. From marsh-marigold-like ancestors might thus evolve primitive anemonies through the indirect effect of drier conditions acting along the same lines and producing the same results as Lamarckians maintain Avould come from the direct effect of the same environment. During their evolution these anemonies might become differentiated into sun-loving and shade-loving species ])y the survival of those individuals best fitted to grow in sun or shade respec- tively. Success in the dry open fields would be favored by having the leaves lie next to the ground, so as to avoid as much as possible the withering effect of drying breezes, while in the shade it would be advantageous to have the leaves elevated so as to catch the light. This maj' account for the occurrence of ground rosettes in the anemonies of the open and the prevalence of raised rosettes, borne upon an elevated, lower internode, in anemonies of the wood. These latter might similarly be differentiated through natural selection into shade-enduring anemonies on the one hand, and climb- SELECTED ADAPTATIONS 451 ing clematises on the other, according as the individuals of successive generations were born with the ability to make the most of the little light, or the ability to climb into the sunshine above. Now, since we are deriving these climbing plants from rosette-bearing ancestors it is easy to see how rosettes might pass into whorls of a few leaves and the few be reduced to two. • We should then have the opposite leaves, characteristic of clematis, arising as an incidental result of the development of the climbing habit. So likewise the peculiarity of having four sepals, which characterizes the genus, may be an incidental result of the opposite leaf- arrangement, for we have only to suppose that such a funda- mental change of habit in the growth of the foliage-leaves would show also in the arrangement of the floral leaves since these would be in a primitive condition readily permitting the change. Other changes involved in passing from the marsh-marigold-type to the clematis-type of flower and fruit, which we have already seen to be advantageous under the drier, sunnier, and windier environment, may be easily imag- ined to have been effected by the accumulation through heredity of innumerable spontaneous variations, each very slight but of vital importance to its possessor in the struggle for existence. According to the view above outlined, more and more highly developed groups would be separated from relatively primitive ones through the perpetuation of slight yet favor- able fluctuating variations, fitting their possessors to occupy the more and more trying environment. At the same time the more primitive forms would survive under the less exact- ing conditions and perfect their simpler structure. Inci- dentally there might be preserved through successive genera- tions acquired peculiarities of an adaptive sort or even nonadaptive ones, provided they were not seriously injurious; or, under the same proviso, there might be perpetuated such a characteristic feature as the plan of four in the calyx of clematis, which had arisen as a merely incidental resuH of some other modification. A pecuharity depending in this way upon another peculiarity is called a correlated character. Occasionally features of no conceivable use to their possessors, 452 KINSHIP AND ADAPTATION as for instance the so-called rudimentary ovules of clematis, may escape entire obliteration. Characters of this sort are termed vestigial. Both vestigial and correlated characters imply adaptations — the one past and the other present — and thus may be said to result indirectly from natural selection; while even the acquired characters permitted by natural selection are most likely to survive when adaptational. Hence we may conclude that the central idea of Darwinism is the gradual accumulation through inheritance of slight selected adaptations. 168. Acquirement versus selection. We have seen that the chief difficulty which the Lamarckians have to face comes from their unproved assumption that acquired charac- ters may be fixed by inheritance. The Darwinians on the other hand in their efforts to avoid this difficulty have fallen into others which we must now examine. Darwin tells us that he made it a rule to note down every fact or criticism adverse to his theory as soon as it came to his attention; for, as he shrewdl}^ observes, what is unfavorable to one's view is most likely to be forgotten. AVith the utmost candor he discussed in his writings every objection known to him. He was thus his own severest critic, and since he pointed out to his opponents their most effective lines of attack, there rightly belongs to him a share in whatever victories they gain in the cause of truth against his theory. Surelj' no one would rejoice more genuinely than he in any l^etter explana- tion of the workings of evolution. Since natural selection operates only through adaptive variations we should expect that the various systematic groups of plants and animals, representing as they do the surviving branches of the evolutionary tree, would be very generally definable by adaptive characters or at least by characters which clearly imply adaptations past or present. But on the contrary it is just this sort of character which is found to have least systematic value, and therefore as a rule we find systematic groups most clearly defined by pe- culiarities which so far as we can tell have no relation what- ever to the vital needs of the organisms possessing them. In tracing the supposed evolution of clematis we chose a few ACQUIREMENT VERSUS SELECTION 453 features as adaptive as possible; but even here we have to admit that the features which best distinguish clematises from anemonies are the ones that are least obviously adaptive. Thus, for example, it would seem to be highly improbable that the life of a plant or the welfare of its offspring could ever depend upon whether it had four or five sepals, and in our endeavor to connect this character with some adaptative feature we had to make a succession of roundabout supposi- tions. Yet most species of clematis are distinguished from anemonies by this very character, while the sharpest distinc- tion between the flowers of these genera is in the sestivation. Here purely mechanical causes seem sufficient to account for clematis having the valvate form while anemony has the imbricate arrangement. A review of our generic, family, and ordinal definitions will show that the main dependence of systematists is upon just such non-adaptive characters as those of floral plan, leaf arrangement, or mode of branch- ing. If from this very large class of non-adaptive characters we subtract all the cases which give evidence of being either vestigial or correlative, we have left a considerable number inadequately accounted for by natural selection. It does not help matters for Darwinians to plead that we are very ig- norant of the functions of all living things, and hence that peculiarities seemingly useless may really be useful; for questioning our ability to distinguish Avhat is useful from what is not tells against our suppositions regarding the uses of parts quite as truly as it does against a belief in their use- lessness. Lamarckism seems weakest when it attempts to account for highly developed adaptations; Darwinism when it deals with non-adaptive characters. We are led into further difficulties by Darwin's assumption that the great intensity of the struggle for existence resulting from over-production would suffice to perpetuate even slightly useful peculiarities. If v/e ask ourselves what really happens to the large number of seeds rij^ened by each genera- tion, we cannot fail to see that the struggle which Dar- winians suppose to result from this immense number is much overdrawn. I am writing these lines in a pine grove. The trees are loaded with cones and from them come whirling 454 KINSHIP AND ADAPTATION down thousands of seeds. But after hunting seedlings ■within and around this grove for man.y years I find that scarcely one in many thousand seeds ever gets a chance to sprout. There is seldom any crowding of the seedlings. The nearest neighbors may be many feet or many j'ards apart, and the saplings are much fewer than the seedlings. Some advantageous position with reference to light or depth of soil would account fully for their survival without any refer- ence to small peculiarities in the plants themselves. More- over, at bearing-time the question as to which trees shall send seeds to such favorable spots seems to be decided not so much by any peculiarities of the trees themselves or their seeds as by the strength and direction of the wind at a given moment and the obstacles that may happen to stand in the way. It does not appear that fitness is decisive. There is some crowchng. Indeed the grove itself might be called a crowd of pine trees. But this crowding simply show's how many plants can grow for many years close together by individual adaptation to one another. The signs of such mutual accommodation are much more apparent than any signs of competition. As applied to this grove the idea of an intense "struggle for existence" among its components would seem to be quite fanciful. One might urge that a Darwinian need not suppose any new species to be arising under the conditions described. Very true; but our illustra- tion was not chosen to show how species arise. It was selected as fairly representing conditions to be met w'ith on every hand — conditions essentially similar to those under which all evolutionists believe that new species have somehow originated. An extreme case such as might be afforded by desert con- ditions increases our difficulties. Desert plants are always few and far between. There always seems to be room for many more. Competitions depending upon a surplus of individuals would appear in general to be quite out of the question. To be sure, each individual may be supposed to have a hard time grov/ing under such severe conditions; but the fact that it lives there shows that it can stand them, and it seems to be enabled to do so by means of extraordinarily ACQUIREMENT VERSUS SELECTION 455 perfect adaptations to its strange environment. We are warranted in believing that tliese plants could not live there unless they had some such adaptations, ])ut just where ex- treme adaptations are most necessary there is least compe- tition to account for them. But may not the environment operate selectively nevertheless? Perhaps, but even so it is not through the struggle of numerous competing individuals: any one of them that is favorably situated and is just able to stand the worst of the drought has as good a chance to in- crease and multiply as the toughest of all. It may also be pointed out that the most marked features of desert plants — such for example as extensive root system, succulent or greatly reduced foliage, hairy or thickened skin for checking loss of water, and an armament of thorns for defense against animals — are the ones most easily accounted for as originat- ing from direct effect of the environment or individual re- sponse; while as regards the defensive armament, Avhich is often cited as a most perfect adaptation, it must be said, that grave doubts are raised as to its being of much use in the very cases where it is most forbidding, since few if any large browsing animals are found in those localities where the most highly developed armaments occur. In such cases any selective influence is hard to imagine. Naturalists have found many cases in which a selective influence, supposing it to exist, would have no opportunity to act upon small fluctuating variations in the Darwinian way. The climbing habit of clematis will serve to show what is meant. The coiling of the leaf-stalks by unequal growth stimulated by contact with a support, is an undoubt- edly useful power; but this power, it would seem, can be of service only after it is developed; a very slight curving of the stalk could not anchor a leaf. Therefore we cannot reason- ably suppose that the power to coil was developed from slight curving rendered more pronounced in successive generations by natural selection. Here it is the first step that counts, and it is just this step that the theory of natural selection is often unable to take. Artificial selection, not being restricted in its operation to variations of use to the plant, does not offer so close an 456 KINSHIP AND ADAPTATION analogy with natural selection as Darwinians commonly assume. Nevertheless, cautious observation of plants and animals under domestication is sure to tlirow important light upon what happens in nature, for the artificial conditions being more under control, it is easier to estimate the effects which a given factor (such as heredity for instance) may safely be counted upon to exert. Some cjuite unexpected results have been reached through studies in the history of garden vegetables by Dr. E. L. Sturtevant of the New York State Agricultural Experiment Station. Wishing to gain what evidence he could of "the extent of variation that has been produced in plants through cultivation," he examined all pictures and descriptions in the old herbals — many of them entirely trustworthy records although published two or three centuries ago — and compared them with the more important recent records and with living examples of the forms now in cultivation. It seemed not unreasonable to expect that among so many plants, cultivated for centuries, at least a few examples would be found in which extreme types such as cauliflower, Brussels sprouts, kohlrabi, and other derivations of the wild cabbage, might be connected by a series of slightly differing connecting links. In not a single case has such a series been found. So far as msiy be judged from the evidence, new types are not developed from other types by the cumulative selection of slight variations in a given direction; but they come suddenly, and each is distinct from its first appearance. All that the selection of slight variations ever accomplishes is the improvement up to a certain point of features already well marked; and ex- perience shows that this point is soon reached. A compact fleshy inflorescence, as of the cauliflower for instance, may be made more compact and more fleshy within certain rather narrow limits, and the highest degree of perfection can be maintained only by the most careful cultivation and generous enrichment of the soil. We have already seen that carrots under cultivation exhibit similar limitations. Such facts are as unfavorable to Lamarckism as to Darwinism since both suppose that types have always evolved through slight changes. SUDDEN ADAPTATIONS 457 Without going further into the difficulties which Lamarck- ians and Darwinians have had to meet in their endeavors to apply either theory, it must now^ be apparent that neither of them gives promise of affording complete general satisfac- tion to students of nature. It is hard to believe that acquired characters or fluctuating variations are often accumulated in a way to bring about the development of new species. One is thus driven to ask whether there is any possible way of explaining the course of organic evolution without de- pending upon these discredited assumptions. Some of our foremost naturalists believe that this great problem may be solved through the further study of variations, and on the basis of recent discoveries a new theory is developing with which we may hope to incorporate the main truths that have recommended Lamarckism and Darwinism to their advocates. Sudden adaptation, such as we have seen to be implied in the evolution of clematis, and have found to be one of the chief stumbling blocks of former theories, is made the corner stone of the theory we have now to consider. 169. Sudden adaptations. Professor Hugo de Vries, an eminent botanist of Amsterdam, Holland, was led to a new view of the process of evolution by studying for a number of years the descendants of some large-flowered evening primroses which had been imported from America and had escaped from a garden near his home into a neighboring field where they grew in great profusion, i Among these escaped plants De Vries found a large amount of fluctuating variation in every part, and frequent abnormalities, but what especially attracted his attention was the appearance of two well-characterized forms which he recognized at once as new to science. One of these was distinguished by a short style and no stamens, while the other was peculiar in having smooth leaves of particularly beautiful appearance. Each was represented at first by only a few specimens confined to a particular part of the field as if derived from the seeds of ^ By an odd coincidence these plants are of the form knowTi as (Ejio- thera Lamarckiana , sometimes called (E. biennis var. Lmnarckiana, or (jrandiflora. The flowers, curiously enough, have the striking pecul- iarity of opening suddenly at dusk. 458 KINSHIP AND ADAPTATION a single plant. These three forms were found to come true to seed and when crossed tlie seedHngs were like one parent or the other; or occasionally other new forms were produced, with or without crossing, which were as unlike the parent form as were the two new forms first discovered. In the course of seven generations several such new forms appeared, numbering in individuals about eight hundred out of a total of about fifty thousand plants raised. Similar forms also appeared in the field. All these new forms were distinct types differing from one another in several particulars such as shape and color of leaves, flowers or fruit, and annual, biennial, or perennial habit; and although growing together they did not intergrade. They were thus as sharply definable as species are, and they could be regarded as true species except for the fact that their differences distinguished parent from ofTspring. De Vries regarded them as elementary species equivalent to what botanists have been calling well-marked varieties, races, or subspecies, and as representing the abrupt changes through the accumulation of which species and higher groups arise. He calls variations of this sort mutations, '^ the new forms being termed mutants. Hence we may designate as viutationism this new theory of evolutionary change. Mutationism supposes that from time to time, especially under the influence of changed conditions, some of the in- dividuals of a species bear offspring distinctly different from the parent, often in several particulars, and that the set of peculiarities thus suddenly arising is completely hereditary even when individuals of the new form are crossed with other forms of the same species. That is to say, the progeny from parents of two different mutations are like one or the other parent, and never intermediate as is often the case with crosses between fluctuating variations. If mutations again mutate and Ave have mutants of the second or higher degree, their hybrids may be wholly like one parent or the other, or may be apparently intermediate from having inherited one or more peculiarities from one parent and the rest from the other; but such cases of apparently intermediate forms show new combinations of elements rather than elements of an ^ Mu-ta'tion < L. mutatio, a changing. SUDDEN ADAPTATIONS 459 intermediate sort, each element being always hereditary unless it gives place to a new element through mutation. While the parent form may continue to be inherited un- changed by certain descendants for innumerable generations the descendants of a mutation to which it has given rise may mutate again and again, until finally a form has arisen charac- terized by so many new elements that it is no longer capable of producing offsjjring like those of the original ancestral form. Then a new species has appeared; and by a similar differentiation through many successive mutations, there would arise genera, families, and groups of higher order. Whether the peculiarities of a mutation are beneficial or not is immaterial provided only they do not unfit the or- ganism for living under the conditions where it occurs. If it can gain a foothold either in the same environment as that of its parent or under some other set of conditions a new race or new species may be started. It has been commonly as- sumed by naturalists that every slightest peculiarity of an organism must have some important relation to its welfare whether apparent to us or not, since otherwise we could not understand its fitting into the environment under which it thrives. On this view we should have to suppose that all the peculiarities of the new forms of -escaped primroses repre- sent sudden adaptations; but in that case it must be admitted that very diverse adaptations fit al^out equally well into the same environment. The assumption that every trait must he connected with some use, seems, however, to be quite gratuitous. This supposition is not at all necessary to the theory of mutations, although, as we have seen, it is a neces- sary incumbrance to the theory of natural selection. On the new view we may suppose that a mutation presents fea- tures which may be more or less beneficial, indifferent, or even more or less injurious; yet if it gets into an environ- ment which permits such a form to live, then the traits of each description may become characteristic of a sur- viving group. We all know that however useless or un- desirable defects or bad habits may be, they are not neces- sarily fatal, and are sometimes perpetuated. Thus we can account for the fact that many characters of the highest 460 KINSHIP AND ADAPTATION systematic importance seem to have nothing whatever to do with utility. Yet, we know that many organs do serve marvelously well the needs of the organism. There is no reason, however, why their adaptive features may not have arisen through mutations, even without selection, and we have seen that initial stages in the development of many an adaptation are of so little use that selection could not reasonably be sup- posed to act on them. At the same time it is of course not impossible in other cases that natural selection may operate under certain conditions now and then occurring. Variations of the mutative sort would then serve especially well as steps in the process of species-making, because of the way in which they are inherited, while fluctuating variations might also sometimes contribute to the result, provided incompatible features did not arise as mutations. For the most part, however, selection 'may now be supposed to play only a subordinate role in organic evolution, its effects showing chiefly in the maintenance of a certain standard of perfection in an established type. A plant grows where it can, and it can grow at all only by having the chance, and being fit to take advantage of it. When we have said this we have ex- pressed about all that it is necessary to admit of the doctrine of natural selection. We must remember also that selection has at best but a negative value; it cannot originate any- thing, it can only favor certain individuals by weeding out others. As to mutations, the reader has doubtless already be- come aware of their striking likeness to "special creations." If it could be shown that acquired characters may be passed over from one mutation to another, we might suppose that a direct influence of the environment is instrumental in originating species. We know that it does control individual peculiarities often in a striking way, and may not improbably account for the constant appearance of features sometimes attributed to other causes. The great difficulty often is to decide which of several possible causes may have brought about a given result; and only long continued, careful experi- ments can give a satisfactory answer. So far as we may judge from such extended observations as those of Dr. Stur- EVOLUTION BY CHOICE 461 tevant and others, the direct effects of external agencies Hke the effects of selection are confined to modifj'ing types rather than originating them. Those of my readers Avho have played with a kaleidoscope will remember that as the cylinder is moved slowl}' forward or back gradual changes in the design take place, and any favorite arrangement may be recovered by simply moving the cylinder back to the place where that arrangement ap- peared,— all this being possible so long as the cylinder does not move bej'ond a certain point; for if it gets ever so little beyond that point there is a sudden rearrangement of the elements thereby forming an entirely new design, which may in turn be modified as before by restricted changes of position. The gradual modification of the design within definite limits is like the modification of a type as effected by fluctuating variations or acquired characters; the sudden change is Hke a mutation upsetting the previous equilibrium and estab- lishing a new equilibrium which is not at all disturbed by vacillating modifications. 170. Evolution by choice. To make the foregoing anal- ogy complete we should have to imagine a kaleidoscope with the power of self-movement; for whatever may be the factors which bring about mutations, the process is somehow influ- enced from within. A living thing is active as well as passive. The idea is thus suggested that organic evolution may have as its controlling factor some power of choice, essentially like our own, residing in all living organisms — a will as truly free, although apparently very cUfferent because exercised under very different conditions. This is a hard saying, but perhaps we shall find it to contain important truth. • Doubtless to many readers the idea of plants willing or choosing in any way whatever will appear quite absurd. " How is it possible," they will urge, "to conceive of voluntary action in vegetable life?" Let us try to consider the matter without prejudice. Surely, as we watch plants they seem to act spontaneously, to imprgve opportunities, and, some of them at least, appear to have gained experience. All ob- servers would agree that a climbing shoot or a root-tip acts almost as if it were intelligent. If the reader will admit that 462 KINSHIP AND ADAPTATION plants in their responses to outside influence are sometimes capable of acting in one way rather than in another way which is equally possible, then all that is essential to what is here meant by choice will be conceded, and he jnay be willing to entertain an hypothesis wdiich squares well w'ith what we know of all living things. In such a hypothetical view we need not suppose that every action of every creature is an act of will. Many of our own acts are, as we say, mechanical or habitual. We may well suppose that most of the behavior of lower organisms, including the behavior of growth, is of this sort. Nor do we need to suppose that consciousness more than very remotely like our own accompanies any of the actions or reactions of plants. All the hypothesis reciuires is that sometimes, even with dimmest consciousness, any organism may be free to choose at a critical moment between alternatives profoundly affecting its constitution. By way of example let us suppose the seeds of a primitive buttercup to be carried near the seashore and to begin to sprout. Such plants are not accustomed to so much salt as would then be in contact with their roots. Here is a change of condition, favorable, as we have seen, to the occurrence of mutations. It has been found b}' experiment that plants of the same kind placed under the same conditions will absorb different amounts of the same substance, as, for instance, common salt. Thus of several seedlings the same in kind and age, growing with their roots in the same salt solution, some will absorb a larger percentage of the salt than others, and, indeed, may be poisoned while others survive. Some- times even the same individual may respond differently at different times. Now, what we may suppose to happen, according to our hypothesis, in the case of the buttercup seedlings is that some of them might choose to keep out so much of the salt that they could not get water enough to live ; others might let in so much salt as to be poisoned by it ; while still others might let in just enough salt to permit their having sufficient water, but not so much salt as would kill them. The survivors, as a consequence of their choice, would have their sap saltish and thus every organ would be affected in an unwonted way. Their seeds would start with EVOLUTION BY CHOICE 4G3 some salt in them already, and this might favor the seedlings enduring a larger amount of salt as they grew. Sooner or later the constitutional equilibrium of the plants would be so disturbed that a mutation would result. Several successive mutations might occur as seeds fell into Salter and Salter localities. At last would appear a form like our seaside crovrfoot (Fig. 303) able to thrive where the salt is strong and showing many marks of its effect. The first mutation would give an hereditary salt-preferring type, while a succes- FiG. .303. — Seaside Crowfoot {Ranunculus Cymhalaria, Crowfoot Family, Ranunculaceoe). (Britton and Brown.) — Perennial herb 4-22 cm. tall; leaves fleshy, smooth throughout; flowers yellow; fruit dry. Native home, Northern North America and Eurasia. sion of mutations caused by similar responses would produce a distinct species. The case of our stranded buttercups might be paralleled by an animal which in time of famine, was reduced to the choice of eating or rejecting unaccustomed food, and as a result of eating enough of it to sustain hfe, being modified in its habits and structure to the point of producing muta- tions. Whatever share in the final result of such an evolu- tionary process we may attribute to acciuirement or to selec- tion we are still free to believe that it is the choice of 464 KINSHIP AND ADAPTATION individuals confronted by alternatives which ultimately de- cides whether a given path shall Ije followed or not. That is to say, external conditions and previous decisions while they restrict the range of choice yet permit of choosing. Of course the reader will not suppose that our imaginary examples afford any real proof of volition in plants or animals. If either do have the power of choice we cannot hope to prove it any more than we can prove that we have such a power ourselves. What has been said is meant merely to show how one who believes that every living thing can choose, may think of evolutionary processes in terms of his belief. With this bare hint of a way of avoiding the pitfalls which await any purely mechanical explanation or any theory of evolu- tion by chance, the reader must be left to make such further applications of the hypothesis as he can. We may call this view, which refuses to regard any living creature as a mere mechanism, Evolution by Choice, since for want of a better name it will serve to emphasize the essence of the belief, which is that a certain measure of self-control is inherent in every organism and that upon this inscrutable power hangs the destiny of the living world. 171. Evolution in general. The creation of living things by successive steps, one growing out of another, is viewed by modern science as part of a gradual process of world- making which is understood to proceed in a somewhat similar manner. That is to say, the entire universe is believed to have evolved and to be evolving according to laws of change which have been the same from the beginning and will be the same to the end, or forever, if the process be endless. The view most widely accepted is that from a vast nebula or vapor-like mass of incandescent star-dust, like those now seen in various parts of the heavens, our solar system for example wdth its central sun, its whirling planets and their moons, has slowly. developed during countless ages, through the agency of gravitation acting together with other proper- ties of matter. During the course of its evolution each sphere is supposed to pass from a ne])ulous condition to a ball of glowing Hquid, which, as it cools forms at first a solid crust, EVOLUTION IN GENEIUL 465 and finally becomes cold and firm to the core. This view of world evolution is called the nebular hijpothc^U.^ According to the nebular hypothesis, as the molten in- terior of our earth lost heat it shrunk away from the solid crust, which, following it warped and wrinkled in an uneven way somewhat as the skin of a drying apple wrinkles to fit the shrinking pulp. AVhen the earth was cool enough at the surface to permit condensation of the atmospheric watery vapor and its fall as rain, seas began to form in depressions between the upheaved regions of dry land. Subterranean forces, connected with the further loss of heat, continued to wrinkle the land into chains of mountains. ^leanwhile storms, controlled by heat from the sun, brought water to the highlands from the sea to which it returned in streams cutting through the land and carving the surface into varied shapes. The rock waste carried seaward settled off shore, as layers of gravel, sand, or mud. These deposits in time became compacted into solid rock and were slowly upheaved again above the level of the sea. This new land was again washed into the sea or may have sunk beneath it and been covered by ncAver washings which later may have been again upraised. From such working over of the crust, most of the land, with its man}' layers of rock or soil (which is rock waste on its seaward way) came to be as it is. From the many changes thus wrought — some gradual, some sudden — involving wide swa}' of air and water currents, and the continual though slow redistribution of rock materials — from all this has resulted a greater and greater variety of climate and soil — in a word, a progressive differentiation of the conditions affecting life. This differentiation represents more and more ' A rival view known as the planetesimal hypothesis has of late years been gaining ground among geologists. This differs from the nebular hypothesis in supposing that such a solar s.ystem as our own evolves by the slow aggregation of innumerable small cold solid bodies (plane- tesimals) moving through space in rings or orbits like those of our planets. The\' are consequently drawn together without much violence into larger and larger masses b}' mutual attraction until there is formed a central sun and planets none of which at any time are altogether gaseous or liquid. Once these larger spheres are formed, other forces than those of mere shrinking with loss of heat are assumed to account for such geologic changes as those of which we have evidence. 4()() KINSHIP AND ADAPTATION variod sets of conditions offering fresh opportunities for living tilings. Life as we know it is possible only below a certain tempera- ture. The greatest heat in which living things are found to grow is that of certain hot springs where, it is reported that a centigrade thermometer registers about 55° (equivalent to 131° Fahrenheit). It will be remembered that water scalds at about 60° t '. or 140° F. Under these extraordinary conditions, certain microscopic plants of most simple organi- zations are found to thrive. ^ It is fair to assume therefore that living creatures could not have appeared upon the earth until the crust had so far cooled that the waters were con- siderably below their boiling-point. Since the simplest forms of life we know and the oldest fossils we have, are aquatic, it is probable that the first living things appeared in the water ; and since all the animals we know depend directly or in- directly upon vegetable food, it seems most likely that the earliest organisms were plants and that from them animals evolved. Confining our view to the vegetable kingdom, which here chiefly concerns us, we may picture to ourselves its evolution as proceeding in a general way from plants of comparatively simple organization, to those whose structure is more and more complex, greater morphological differentiation accom- panying fuller physiological division of labor. Such increase in complexity we speak of as progress from lower to higher organization, without meaning to imply t-hat the higher forms are any more perfectly adapted than the lower to their respective environments. Indeed the simpler forms may be so well adapted to the less trying conditions that they may persist through countless generations essentially unchanged, provided thay have the opportunity to live in the kind of environment which suits them. Thus we find to-day, growing in water, plants which may be fairly supposed to have retained the main features characteristic of the pro- genitors of the vegetable kingdom. 1 Experimont shows that the spores of other very simple plants are not killed by a temperature considerably above that of boiling water, but they cannot grow under such conditions. EVOLUTION IN GENERAL 467 Many types of structure have become extinct, because changing conditions no longer afforded a suitable environ- ment, or, perhaps because no mutations of the old form could adapt it to new circumstances of pecuHar difficulty. Relics of types which the world has thus outgrown have occasionally come down to us as fossils caught in the deposits which be- came rock in ages past. Sometimes a group, or perhaps part of its members, may have escaped extinction through the appearance of mutations Fig. 304. — White Water Crowfoot (Raiiuiiculufi aquatilis, var. capillaceus. Crowfoot Family, Ranunculacece) . Plant, about J. Flower. Fruit. (Britton and Brown.) — Perennial (?) herb about 30 cm. long; leaves submerged; flowers wliite; fruit dry. Native home. North America and Eurasia. fitting the individuals to five under less exacting conditions which therefore would permit simpler structure. Thus a buttercup able to live in water without being drowned could dispense with much of its root system and stiffening frame- work and so come to resemble, in the adaptation of its vege- tative organs to an aquatic life, a lower form of plant none of whose ancestors had been terrestrial. The white water crowfoot (Fig. 304) of our ponds and streams is a buttercup which we have every reason to believe has thus descended from a land species. In so far as a type of organism or organ 468 KINSHIP AND ADAPTATION becomes simplified in the course of its evolution and, so passes to a lower level of structure, it is said to degenerate. Aluch more extreme instances of degeneration will be dealt with in the following chapter. It thus appears that degeneration, persistence, and extinc- tion of types accompanies the general progress wliich charac- terizes organic evolution. In the evolution of human society likewise we find degeneration, persistence, and extinction of races along with a general progress of mankind from savagery to civilization. Here as in the evolution of lower organisms we may observe adaptation to changed conditions through sud- den or gradual modification. Migrations also play an import- ant part and have many consequences, among which conflicts are the most apparent although not necessarily the most sig- nificant. Periods of greater progress have been times of greater peace. Conflicts destroy or test; they do not create. Men or races unfit to live, if such there be, of course are better dead', and those menacing the progress of mankind are better subdued; but it is surely a partial view of human affairs that regards the world as one vast battlefield whose horrors have fostered the most precious characteristics of civilization. How- ever inevitable mortal conflicts have been, however fierce the struggle of competition, and however necessary it may have been to kill the worse that the better might live, we cannot say that anyone has been made better by the killing. Yet we may be sure that human advance toward the most perfect and abundant life has been delayed, and that whatever real progress Man has made has been in spite of his competitive struggles. The economies of co-operation and the advantages of mutual service achieve what competition never can. Mere struggle for supremacy when fiercest destroys most of w^hat is best. Man's mastery over nature and over his lower self has come through learning and choosing the better way. The evolution of mankind and that of lower organisms are alike in so many ways, it is thought that each maj' throw light upon the other. In human progress we recognize as the controlling factors of change: Opportunit3^ — offered by the environment; Experience, — representing its effect; Choice, — as the response to it, guided by Ideals. Of these the pivotal EVOLUTION IN GENERAL 469 factor is Choice, for by it oi)portuiiities are improved, (wpcri- ence (leterininocl, and ideals pursued. What we ourselves antl what former generations have chosen to do or endure is most largely responsible for what we are. Thus human affairs center about the human will. So throughout God's world we are led to look for some opportunity offered to every creature, some experience by which it may profit, some choice of its own, and some divine guidance. Man's choosing of the better way has led him heavenwards toward the highest, fullest life. As from a mountain side he may now look back and with the mind's eye catch glimpses of his path and of the forking paths of fellow creatures many of whom have been as comrades at different stages of the long, long journey. Traced backward all the paths seem to converge at the horizon as if all had come from the same point. Some of them, as they advance, keep to the level of the sea continuing always much the same; others climb for awhile to higher levels, then turning aside and traversing an easy plateau end at a precipice; still others after climbing for a while decline to lower levels; while others yet keep climbing and attaining various heights. Man's path soon left the kingdom of plants, and ascending through the realms of worm, fish, reptile, and brute has reached at last the mountain path which leads beyond the clouds. Viewed broadly the progress of the world is seen to be orderly, and shall we not say, well ordered? New forms of life have come promptly to enjoy the ever increasing oppor- tunities afforded by the evolving earth. Advance has been made not without difficulties, which being overcome have brought out the finest traits. Nor has there been lacking continual occasion for mutual help, and this has ever multi- plied the blessings of life. CHAPTER XII LIFE-HISTORIES 172. Cycles of life. Every creature which completes its span of life passes through various stages of development from germ to adult, and ma\' in turn give rise to similar germs which may continue the process in endless round. Hence, until we are acquainted with the cycle of changes which normally characterizes a certain kind of plant or animal, we do not know it at all thoroughl}'; but as with adult structures so with life-histories, the knowledge of a few tj^pical examples gives a general knowledge of many because of the inheritance among kin of fundamental resemblances. Moreover, since the life of the individual, as we have seen, more or less clearly repeats the series of ancestral forms, a knowledge of life-histories throws an important side light upon the relationship of different groups and helps us to picture the earlier stages through which a type has passed in its evolution. In the comparatively small space here availal^le we cannot hope to do more than glance at the form and behavior of a few typical plants through the various stages of their lives. We shall, however, choose examples exhibiting so wide a range of peculiarities that the student may gain finally a comprehensive view of the vegetable kingdom sufficient for an introduction to more special study. 173. The blue algae (Class Cyanophyceae). Among the useful plants we have studied the onl}' alga is the so-called carrageen or "Irish Moss" (see page 112), and this, as we shall see, belongs to one of the most highly developed classes of seaweeds. It agrees with the great majority of algse, however, in being aquatic and containing chlorophyll, and in being without true stem-, leaf-, or root-members. Before 470 THE BLUE ALG.E 471 passing to a more detailed examination of the higher algse it will be most instructive for us to study some of the simpler forms. About as simple as any are the exceedingly minute plants which for want of a better name we may call tint-ball algiB (Chroococcus), and which when highly magnified present Fig. -iOo. — Tint-ball Alga, (Chroococcus turgidus. Tint-ball Family, Chroococ- cacea). A, plant as ordinarily seen; magnified about 400 diameters. The inner shaded mass of protoplasm is bluish green, surrounded by a transparent gelatinous envelope. B, same, beginning to divide into two plants. C, the division advanced by the formation of a double wall between. D, the division complete. (Redrawn from Kirchner.) — Found in swamps and on wet rocks throughout the world. the appearance shown in Fig. 305. An individual {A) consists merely of a spheroidal mass of rather firm consistency and blue-green color, surrounded by a transparent gelatinous envelope. Near the center of the mass may be seen under favorable circumstances a comparatively small, somewhat denser spot. After the plant is dead, the application of pure water dissolves out a blue substance — called phycocyanin i — leaving the yellow-green chlorophyll. This in turn if dis- solved out by alcohol leaves a colorless, minutely granular material which examined chemically would be found to consist of a highly complicated mixture of proteids. To such a mixture of organized proteids the name protoplasm - has been given. This when active forms the living part of the plant. Whatever is alive in any plant or animal is protoplasm. Hence protoplasm has been called "the physical basis of ^ Phyco-cy'an-in < Gr. phykos, seaweed; kyaiios, blue. 2 Pro'to-plasm < ML. proto plasma, the first creature made < Gr, protos, first; plasma, anything formed. 472 LIFE-HISTORIES life." Its exact chemical constitution is not known, nor does it seem likely that it ever can be known ; for to analyze a sample of protoplasm chemically is to kill it, and dead pro- toplasm surely differs in important ways from protoplasm alive. Moreover, through the many complicated reactions going on within, any active mass of protoplasm is doubtless continually changing its composition. One of the products- of the activity of the protoplasm of a tint-ball is the blue substance above mentioned; another product is the chloro- phyll by means of which it is able to make food in the sun- light like any other plant containing leaf-green. Still another product is the gelatinous material forming the envelope by which the little mass of protoplasm is surrounded. Chemical tests would show that this envelope consists of a kind of cellulose. The food which the protoplasm is able to make from the substances it absorbs through its cellulose shell from the surrounding water, is used by the plant as material for growth. That is to say, it uses the food to make ncAV protoplasm out of which come new coloring matters, new cellulose, and other organic products. As the growth of the sphere is mainly in one direction it becomes elongated into an ellipsoid as shown at B. Meanwhile, the denser central part of the protoplasm has similarly elongated and finally divided into distinct halves. These halves move toward the ends of the ellipsoid, thus becoming surrounded on all sides by the thinner protoplasm. Soon there appears in the ellipsoid a plane of separation extending through the center at right angles to the long axis; then each of the portions of protoplasm on either side of this plane becomes larger and rounder, and each along the plane of separation builds a laj^er of cellulose which presently appears as a cross parti- tion (C). At last, as a result of further growth and rounding we have two distinct spherules of protoplasm, each with its central, denser part and each surrounded by its own cellulose envelope essentiallj^ like the original tint-ball. Thus through growth and division one plant has become two. These plants may remain attached to one another and each of them may divide again and repeat the process a number of times Avithout separating. The result then is a colony in THE BLUE ALG.E 473 which all the stages in the life-history of the individual may often be observed. We neetl a few technical terms to designate such parts as have just been described. A mass of protoplasm capable of more or less individual activity is called a ccll.^ All plants, and all animals as Avell, consist of one or more cells. Usually in plants the protoplasm is inclosed b}' a cellulose envelope known as the cell-wall, all within which is then chstinguished as the cell-contents. Since a cell-wall implies at least the previous existence of living cell-contents, the term cell may be applied even to the empty chaml^er from which all life has gone. In the living protoplasm a comparatively large, dense kernel, more or less clearly marked off, is termed the nucleus,'^ the rest of the protoplasm being distinguished as the cytoplasm; ^ while any liquid part of the cell-contents is called cell-sap; and the entire protoplasmic part, a protoplast. The process through which one cell becomes two by enlarging and splitting in halves is known Sisfissimi.* Successive fissions often take place in such a way that the partitions are in planes at right angles to one another, with the result, shown in the tint-balls, that more or less cubical groups of cells are formed — an arrangement which sometimes passes into a globular or irregular one through changes in the direction of growth or division. If instead of forming partitions at various angles, the cleaving planes are always parallel, so that successive fissions are in the same direction, then we have a chain or row of cells. This is what happens in the colonies of algae known as "fallen stars" (Nostoc, Fig. 306), because of the sudden appearance of their glisten- ing balls when swollen by rain. Here numerous blue-green cells, like beads on a string, are embedded in a copious mass of jelly secreted by the protoplasm; for instead of forming distinct cell-walls this mucilaginous cellulose, for the most part, becomes homogeneously fused. At intervals in the ^ Cell < L. cclla, a small room or hut. - Xu'cle-us < L. a little nut or kernel < nux, nut. ^ Cy'to-plasm < Gr. kytos, a hollow or cell. Originally a synonym of protoplasm, the word cytoplasm has now taken on the restricted Bense above defined. ^ Fis'sion < L. fissio, a dividing. ' 474 LIFE-HISTORIES chain somewhat larger cells are formed, each with a distinct wall. Certain of these cells, called heterocysts ' have most of their protoplasm replaced by a pale or colorless cell-sap and Fig. 306. — Fallen Stars {A'ostuc spp., Fallen Star Fanul\', Xostucacecp). A-F, Nostoc paludosiim. A, chain-colony with resting spores near the middle and heterocysts at the ends, 'p. B, resting spores. C- F, germination of resting spore, and stages in the formation of a new chain-colony. G-J, N^ostoc sphwricuin. G, gelatinous balls as they appear in moist earth, 3 natural size. H, part of a slice cut through the ball, ^a. / early stages in a growing colony, -';". (.Janczcwski, Thurot.) — Protoplasts bluish green, enveloped in a gelatinous mass which they produce. Found mostly in water or on moist earth in various parts of the world. become incapable of further development. At points where the heterocysts thus limit growth the chain eventually ^ Het'er-o-cyst < Gr. hcieros, different; kyslis, a bag. THE BLUE ALG.E 475 breaks into short lengths each made up of a comparatively small number of cells. These groups are termed hormogonia.^ While the cell-row is dividing into hormogonia the gelatinous envelope is becoming fluid, and as the hormogonia separate they are observed to take on a swaying, worm-like movement which enables them soon to pass into the surrounding water and travel in various directions. In a little while they come to rest, secrete a new gelatinous envelope, and by repeated fission of the cells develop a new colony. On the approach of adverse conditions, such as those of winter, certain of the cells protect themselves by a dense wall, store up food in the cytoplasm, and become brownish. In this condition they are very resistant of cold and tolerant of drying, and are thus able to survive unharmed under conditions which destroy the other cells. These resistant cells are called resting spores. When the other members of the colony perish and the mucilaginous envelope dissolves, these spores are set free ; and on the return of f avoral^le conditions they germinate by a swelling of the protoplasm which ruptures an outer dense layer of the wall. Covered then by a thin, inner layer the protoplasm elongates, as shown in Fig. 306, B, C, D, and by repeated fission together with a copious secretion of jelly a new "fallen star" colony is started. Nostoc and Chroococcus may be taken as typical of the Class Cyanophycese the members of which occur abundantly in salt or in fresh water or on surfaces frequently wet, and are characterized by having their chlorophyll more or less inasked by phycocyanin, arid by consisting of single cells or cell-colonies of various form, reproducing only by fission, although the colonies sometimes midtiply through hormogonia or resting spores. The lower members of the class have about the simplest organization known. They are doubtless as much like the earliest organisms which appeared upon the earth as any creatures now living. It is interesting and perhaps signifi- cant, that the algse previously referred to as thriving in the scalding water of hot springs, belong to this class. From an economic point of view the blue-green alga3 have an especial importance as being the chief cause of offensive odors which ' Hor"mo-gon'i-um < Gr. hormos, a chain; gonos, offspring. 476 LIFE-HISTORIES develop at eertain seasons in the stored water-supply of many cities, often rendering it unfit for use. Through experi- ments recentl}' performed on a large scale by the United States Department of Agriculture, it has been found that an exceedingly minute percentage of copper sulphate added to the water will kill them and other harmful plants without leaving any traces of itself which are either perceptible or harmful to man or beast in the slightest degree. 174. The green algae (Class Chlorophyceae) include many familiar water plants. They are characterized bj' havit^g the chlorophyll ordinarily un- masked bij any other pigment, their structure and their metiwds of reproduction incliuling widely varied types. A very simple form, common throughout the world on rocks or tree-trunks which are often wet by rain, is the wall- stain alga (Pleurococcus) shown in Fig. 307. Except for the absence of blue pigment it is much like a tint-ball alga. The cell-wall of this alga is ordinary firm cellulose, the nu- cleus is more distinct than in the tint-balls, and the proto- plasm shows further differentiation in the presence of special- ized bodies of varied form called chromatophores,^ to which the chlorophyll is confined. Reproduction, as ordinarily observed, is by fission in three directions; and, since the cells often remain attached, more or less globular colonies result. Further development under certain conditions has been reported; but however that may be, the life-history of the plant as commonly seen consists simply of fissions re- peated indefinitely. Somewhat higher in organization are the 3-ellowish green, uni- cellular, fresh water algse known as desmids, of which Cosmariinn (Figs. 308-310) is a typical genus. Desmids are of varied and often strikingl}' beautiful forms, the firm, cellulose wall being sometimes curiously sculptured and frequently developing sharp projections, while the chromatophores take the form of disks, plates or bands symmetrically arranged. Within the chromatophores may be seen transparent spots called pyrenoids - in which starch is formed. Many of the genera have the plant-body constricted in the middle, as in Cosmarium, forming thus two semicells; and in all cases tlie halves are symmetrical. This peculiarity modifies in an odd way ' Chro'mat-o-phore < Gr. chroma, color; phoros, bearing. - Py-re'noid < Gr. pyren, the stone of a fruit; eidos, resemblance. THE GREEN ALG^E 477 Fig. 307. — Wall-stain Alga {Plcurococcus vulgaris, Wall-stain Family, Pleurococcacea;) . Plants showing fission in various directions, ^i^. (Wille.) — Growing commonly upon moist rocks, bricks, and tree- trunks, forming extensive green-stains, throughout the world. Fig. 308. — Grape Desmid (Cosmarium Botrys, Dcsmid Family, Desmidiacece.) I-III, stages of fission, ^l"-. (DeBary.) — Bright green. Common in fresh water. il .7 ■f . A kJ.-^^1 Fig. 309. — Grape Desmid. A, first stage in conjugation; the two halves of the celi-wall (b) have been broken apart by the protruding protoplast (c). B, later stage; the protoplasts of two plants are coming together. C, final stage; the two protoplasts have fused into one mass to form a zygospore (/) leaving the old cell-walls (c, b) empty. D, E, F, stages in the ripening of the zygospore which surrounds itself with a pro- tective wall from which numerous projections finally arise, ^^ (De- Bary.) 478 LIFE-HISTORIES the process of fission, by which they multiply under ordinary con- ditions. As shown in Fig. 308, the outer firm layer of the wall, ruptures at the place of constriction, allowing the semicells to separate, while the protoplasm of the isthmus or neck wiiich joins them elongates, being still covered by a thin, elastic, inner layer of cellulose. The nucleus and chromatophores divide, half going to either end. A partition is then formed across the middle of the isthmus, and the new part on either side grows larger and rounder until finally two separate and complete cells are formed each with a new and an old half. Meanwhile chromatophores pass over into this new semiccll, and its outer wall becomes thickened and sculp- tured like the other. In some desmids after fission the cells remain attached forming a row comparable to the chain in Xostoc. A striking peculiarity of the free forms like Cosmarium is their power of locomotion. While not rapid, the movement is quite perceptible under the microscope. It has been found to be accomplished by protrusions of mucilaginous material, and its direction to be in- fluenced by light. Resting spores are produced in the peculiar manner shown in Fig. 309. Two cells lying side by side, each rupture the outer wall across the middle and the halves separate as for fission, but instead of forming a cross partition the protoplasm of each plant flows out of the old cell-wall and toward the other protoplast. When the two protoplasts come in contact thej^ fuse into a single spherical mass, the two nuclei merge into one, the chromatophores disppear, and the whole contents becomes brown- ish, while the outer cell-wall or exospore ^ thickens and puts forth a number of projections. In this condition the spore is comparative!}'' resistant of cold or dryness. On the return of favorable conditions germinations take place as shown in Fig. 310. The contents swell, rupture the exospore, and emerge, surrounded by the delicate inner wall or endospore.- Soon a division of the nucleus takes place fol- lowed by division of the protoplast into halves, which become constricted, turn green and form cell-walls much like the uniting pair from wdiich thej^ w^ere derived. Freed from the endospore the newly formed desmids swim about and multiply by fission, during which process the chromatophores soon become distinct and the cell-wall takes on its characteristic sculpturing. A spore formed as above described by the union of two similar protoplasts is termed a zygospore,^ the uniting protoplasts are known as gametes,* and the process of their union is called conjugation.^ Closely related to the desmids are the "pond-scums," algse which form tangled masses of delicate threads floating near the surface of quiet fresh water. A very common genus is Spirogyra (Fig. 311) ^ Ex'o-spore < Gr. exo, outside; spores, spore. ' En'do-sporo < Gr. endon, within. ' Zy'go-sporc < Gr. zygon, yoke. * Gam'etc < Gr. gametes, a spouse. '■> Con"ju-ga'tion < L. con, together;. /(/(/«;t, join or yoke. THE GREEN ALG.E 479 Fig. 310. — Grape Desmid. Germination of zygospore: A, protoplast emerging; B, protoplast beginning to divide in half; C, division nearly complete; D, division complete within the thin temporary cell-wall; E. the two desmids escaped from the wall; F, one of them dividing by fission; G, the fission nearly complete, ^f. (DeBary.) Fig. 311. — Pond-scum {Spirogyra sp., Pond-scum Family, Zygnemacece). 1, segments of two thread-like plants beginning to conjugate by the protrusion of adjacent cell-walls toward each other. 2, later stages resulting in the formation of a zygospore (6). Much magnified. (Ker- ner.) — Pond-scums abound on the surface of ponds, forming masses of bright green color through the summer which turn brownish toward spring when conjugation takes place. 480 LIFE-HISTORIES in which the plants are unbranched filaments consisting; of a single row of comparatively large cylindrical cells containing spiral, ribbon-like chromatophores, ratlusr j)rominent pjTenoids, and co- pious cell-sap. Elongation of the thread results from fission of the cells much as in Nostoc; but with Spirogyra the more intimate union of adjacent cells gives rise to a multicellular individual rather than to a colony of unicellular plants. Conjugation takes place between cells of separate plants growing near together. Outgrowths from two opi^osite cells meet, and by absorption of the walls at the point of contact form a tube connecting the cavities. Tlirough this Fig. 312. — Pond-scum. Germination of zygospore. I, resting zygospore; /, yellowish-brown layer of the cell-wall; e, outer layer of wall. II, the protoplast emerging from the old wall, covered by a thin wall (g) of its own. Ill, young plant beginning to form a thread-like row of cells by elongating and forming cross-partitions (u\ tv') ; its small end (d) still within the old spore-wall, enclosed by the old cell-wall of the original plant whose conjugating-tube (c) is still visible. Much magni- fied. (Pringsheim.) tube the gamete from one cell passes into the other cell to form a zygospore. Germination takes place in the manner indicated by Fig. 312. What is here especially noteworthy is that in the conjugation of Spirogyra we have a simplest form of sexual reproduction. Whereas in Cosmarium the gametes are just alike, in Spirog.vra the one which passes over might i)e called male, and the other, female, although before conjugation no difference between them is perceptible. Somew^hat more highly developed in both the vegetative and the reproductive system are the green algae of the genus Ulothrix (Fig. 313) which consist of cylindrical cells forming an unbranched filament fastened by one end to a rock or other firm support. These filaments grow so crowded as to form THE GREEN ALGJE 481 a woolly mat which suggests the name wool-weeds as appro- priate for the group. A differentiation of the plant-body appears in a specialization of the lowest cell as an organ of attachment. This, therefore, is analogous to a root while the remaining green part has the function of a shoot. But v-^'r Fig. 313. — Wool-weed {Ulothrix zonata. Wool-weed Family, Ulotrichacew). A, young plant with basal cell (;•) serving as a root-like organ of at- tachment, 3?&. B, part of plant with escaping swarm-spores. C, single swarm-spore. D, formation and escape of gametes. E, free-swimming gametes. F, gametes conjvigating. G, conjugation complete. H, zy- gote. /, zygospore after a period of rest. K, zygospore after division of its protoplast into swarm-spores. B-K, ^m, (Dodel-Port.) — Abundant on submerged rocks, especially in fresh water. the resemblance not being one of homology, it will be most accurate for us to name organs of this kind pseudo-roots and pseudo-shoots respectively. Thallus ^ is a general term for any plant-body in which true roots, true stems, and true leaves do not appear. The pseudo-shoot of a wool-weed elongates by fission of its cells, each of which contains a 1 Thal'lus < Gr. thallos, a young shoot. 482 LIFE-HISTORIES single nucleus and a chromatophore in the form of a nearly complete hollow cylinder. Eventually in some of the cells (B) the protoplasm assumes a spheroidal form or may divide into from two to eight smaller masses each provided with a nucleus through division of the original one. These globular masses soon begin to move and presently make their way into the surrounding water through an opening in the old cell-wall. When outside, however, they are still surrounded by a delicate cellulose meml)ranc, but this soon ruptures setting free the naked protoplasts. Each of these (C) is now seen to be some- what pear-shaped, with a colorless pointed end from which come four slender lash-like projections, called flagcUaA The rounded part is grass-green and contains a bright red granule termed the eye-spot. As soon as they are free, these naked protoplasts swim about with rapid motion, propelled by their lashing flagella. After a while they come to rest, secrete a cellulose wall, and germinate b}^ fission, the lo-wer one of the two cells first formed becoming the pseudo-root by elongation and attachment to the substratum, while the upper cell develops into a long green multicellular thread by repeated divisions. A naked motile protojilast, by means of which a plant is multiplied non-sexually we call a sirnrm-spore. Ulothrix repro- duces also by motile gametes in which may be discerned occasionally a slight inequality in size suggesting the beginnings of difference in sex although for the most part they appear quite alike. These sexual or subsexual gametes arise from the cells of the filament in much the same way as the swarm-spores do, but thej^ are more numerous and smaller, and possess only two flagella (D, E). They unite sidewise (F) with their tips together, thus producing what looks like a swarm-spore (G), with its four flagella, but which differs in having two eye-spots. A protoplast resulting from the fusion of two protoplasts, whether they be alike or unlike, is termed a zygote.- The zygote of Ulothrix soon absorbs its flagella (//), becomes round, and secretes a cellulose wall, thus becoming a resistant zygospore ready for a period of rest. The zygospore germinates by forming several swarm-spores {K) each of which in turn grows into a thallus as already described. In the sheath algae (Coleochaete) the thallus (Fig. 314), is in the form of a flat disk or cushion-like mass attached to some support by the lower surface. This chsk as in the species figured usually consists of branching filaments which elongate by repeated division of the terminal cell and branch by its frequent forkings. {B,a-g). In other species the fila- 1 Fla-gol'Ium < L. a lohip. - Zj-'gote < Cir. z'jgolos, yoked. THE GREEN ALG^ 483 ments instead of being distinct grow together into a mass by the coalescence of adjacent cells. ^Slany of the cells produce hair-hke outgrowths, and they are all uninucleate. Any of the cells maj' form a single swarm-spore like that shown in Fig. 315 D, which, as will be noticed, has but two flagella. Such a spore, after attaching itself to some support, divides into a cell-row Fig. 314. — Free-branching Sheath-alga {Coleochcete soluta. Sheath-alga Family, Coleochcetacece) . A, plant sho^\-ing flat system of branching, and bristle-like outgrowths (/i), ■^i'^- B. part of disk, further enlarged; a-g show successive stages in the branching of terminal cells. (Pring- sheim.) — Thallus forming bright green spots on plants or other sub- merged objects in fresh water, in Europe and America. which by further division becomes a mature thallus. Besides this non-sexual method of propagation a well-marked se.xual reproduc- tion takes place as follows. The protoplasts of certain smaU usually terminal cells (an, Fig. 315, A) become transformed into flagellate bodies like the swarm-spores only smaller (z) ; while other terminal cells (og, Fig. 315, A) enlarge, become flask-shaped by the formation of a long neck opening at the top, and finally contract the protoplast into a sphere at the base. The motile body as soon as it is set free swims to the flask-cell, enters the opening, forces its way down the neck to the large protoplast, and fuses with it. 484 LIFE-HISTORIES The smaller motile protoplast is plainly the male gamete, and the larger, non-motile one, the female. Hence the cells in which they arise may be called respectively the male and the female gametangia,^ the cells in which non-sexual spores appear, being termed sporangia:- Union of a male with a female gamete is dis- tinguished as fertilization. As a result of this process in Coleocha?te the fertilized gamete, still remaining within the gametangium, en- larges, and incloses itself in a new cell-wall, thus forming what is called an oospore,^ which becomes further protected by an envelope of branches (r, Fig. 315 B); for a cell at its base is stimulated to Fig. 315. — Cushion Sheath-alga {Coleochcete pulvinata, Sheath-alga Family, Coleochcetacete). A, part of a thallus bearing male {an) and female {og, og") gametaugia; and bristle-like projections sheathed at the base {h, h); male gametes, z, z, 202. J5, ripe oospore in its rind (r). C, oospore germinating by the formation of swarm -spores {sch). D, swarm-spores of different ages. B-D, «t°- (Pringshcim.)^ Found with the other species, forming small cushions. produce several new cells, which, growing up around the game- tangium-base and oospore produce a sort of rind. Thus protected the oospore rests through the winter. In spring the protoplast, by division of its nucleus and the formation of partitions, is transformed into a little mass of cells firmly united with one another but quite distinct from the old cells surrounding them. In this little mass we have, in fact, a new plant entirely different from the sexual plant which produced it. It never produces gametes, but from each cell comes a single swarm-spore which under favorable conditions ' Gam"e-tan'gi-um < Gr. angeion, a vessel. ^ Spor-an'gi-um < Gr. spora, spore. * O'o-spore < Gr. oon, an egg. THE BROWN ALG^ 485 grows into a sexual plant like the one already described. Tims in the life-history of Coleocha?te a sexual form producing gametes, alternates with a form of plant which produces only non-sexual spores. That wdiich bears gametes is termed the gametophytc,^ while the merely spore-bearing one is the spowphyte.- Each repre- sents a generation; hence the plants whose life-history is thus di- vided are said to exhibit an alternation of generations. 175. The brown algae (Class Phaeophyceae) are charac- terized in general by a brown coloring nialtcr, phycophcein,^ masking the chlorophyll. They are almost entirely marine. Besides many comparatively simple forms there are some showing a remarkably high development of the vegetative system. In their methods of reproduction the brown algae present rather close parallels to various chlorophyceous tj'pes, very rarely, however, exhibiting an alternation of generations. One of the commonest genera is Laminaria (Fig. 316) which includes the familiar leathery "sea-tangles," "kelps," or "Devil's aprons" often cast upon beaches after a storm. The thallus consists of a flat, more or less leaf-like part (pseudo-leaf) attached to a stalk (pseudo-stem) at the base of which is a hold-fast (pseudo-root), often much branched, which clings to stones or other means of anchorage on the bottom. This thallus which may be yards in length consists of an exceed- ingly large number of cells among which a considerable differ- entiation may be observed. Thus in the stalk as shown in Fig. 317 we have an outer group of cells forming a sort of rind (/•, ;•) which is comparatively tough and thus protective, while at the same time it serves as a food-making part since the cells are rich in chlorophyll. Those inclosed by the rind, (p, p) form the chief bulk of the stalk, are pale in color, and serve largely for the storage of food-materials elaborated by the outer cells. In the rind occur numerous cavities (g, g) filled with a mucilaginous material. The pseudo-leaf shows a chfferentiation of cells similar to that of the stalk. For the most part as soon as they are formed the cells lose the power of dividing; but in the region where the pseudo- 1 Gam'et-o-phyte < Gr. gametes, spouse; phyton, plant. - Spor'o-phyte < Gr. spora, spore. ^ Phy"co-phse'in < Gr. phycos, seaweed; phaios, brown. 48C LIFE-HISTORIES Fig. 316. — Sea-tangles (Laminaria spp., Sea-tangle Family, Laminariacece) . Various forms more or less reduced in size; the larger ones often having the stalk over 1 m. long and the expanded part 2 m. (Luerssen.) — These brown, leathery seaweeds are familiar objects along our coasts. leaf joins the stalk there is a cell-mass which retains this power, and from time to time exhibits it in a striking waj^; that is to say, it forms a new pseudo-leaf at the base of the old one which it eventually casts off, as indicated in the figure. Any mass of connected cells all of which are similar in origin and character is called a tissue. An undifferentiated tissue, THE RED ALC;.E 487 made up of cells still capable of division is termed a meristem,^ or is described as meristcmatic, while a fully differentiated tissue is distinguished as 'permanent. Laminaria reproduces only b}^ swarm-spores which are formed in sac-hke sporangia projecting from the surface of the pseudo-leaf. They are crowded closely, together with a number of curiously shaped protective cells called paraplujses.' The swarm-spores have a red eye-spot and two flagella which are attached at the side. There are no gametes. A somewhat higher development both of the vegetative and re- productive systems is found in the genus Fucus (Figs. 318, 319) which includes the common "bladder-wracks" of the sea-shore, so called l)ecause of the bladder-like floats (/) developed in the thallus. The meristcmatic tissue is at the tip of the thallus-lobes. A disk-like pseudo-root attaches the thallus to rocks which lie mostly between tides. The pseudo-shoot has forking midribs with flat expansions on either side in which the inflated bladders often appear. Tliere is a rind and an inner, somewhat pith-like tissue much as in Laminaria. The tips of certain branches become swollen (s, Fig. 31S) and produce a number of small cavities {conceptades) each opening by a pore at the surface and lined with numerous paraphyses among which appear either male or female gametangia (Fig. 3 19, a) . Within a female gametangium (6, c) eight large, spherical, non-flagellate gametes arise and are pressed out into the siurounding water by swell- ing of the paraphyses. The male gametangia, (f/) expelled at the same time emit nmnerous flagellate gametes (g) which resemble somewhat the swarm-spores of Laminaria. They are attracted in large num- bers to a female gamete, and, attaching themselves to its surface, often cause the sphere to revolve by the energetic movement of their flagella (, less familiar, with a unicellular body very much larger than this. Such extraordinary development of a single cell seems not to have THE THALLOPHYTE D I \' I SIGN 511 been a very successful tyi)e of structure except in cases where some adventitious means of mechanical suj)j)ort could be depended upon, or, as in Mucor, disjiensed with because of exceptionally favorable sui-roundings. But at best the utmost limit of size in a single cell is soon, reached, and all large i:)lants and animals consist of innumerable, minute cells. Minuteness of the cell permits as a rule more rapid multiplication, and whether the cells be distinct individuals or the subindividual units of a body-community, minuteness facilitates taking advantage most promptly of all the food available. This principle is strikingly exemplified in bacteria which are at once the smallest organisms known, and the ones ca- pable of most rapid reproduction. Bacteria have been observed to divide at intervals of about a quarter of an hour. At this rate the progeny of one individual would be many millions in a single day. Most plants with a relatively large thallus reproduce vegetativeh'' by setting free minute bits of their protoplasm. Thus most of the aquatic forms, e. g., Ulothrix, Coleocha^te, Laminaria, and Sapro- legnia convert certain of their protoplasts into swarm-spores resem- bling motile unicellular microbes; Avhile the aerial Zygomycetes, Ascomycetes, and Basidiomycetes produce dust-spores. Both swarm-spores and dust-spores besides being quickly formed and readily set free, have the further advantage from their minuteness of being easilj^ and widely dispersed by currents of water or air, just as was the case with the two halves of the ancestral fission- plants. The larger thalloph.ytes throughout their evolution have thus retained, in their formation of minute non-sexual spores, the most primitive method of reproduction, while vegetating by a single enlarged cell or by a multicellular thallus. An obvious limitation of this primiti\e, rapid method of repro- duction lies in the fact that it depends upon a continuance of favor- able conditions for its success in perpetuating the species, whereas in nature such conditions are often suspended through periods of adversity. A very simple organism like Chroococcus living under fairly uniform conditions can bide its time through seasons of cold and drought and resume its very moderate activity when warmth and moisture return. But the chances of injury are decreased and the power of taking prompt advantage of every favorable oppor- tunity to grow, retained, if at the approach of winter, for example, the tender protoplasts harden by getting rid of superfluous water, become invested by a thicker, firmer wall, and store up what food they can instead of spending it all in immediate growth and re- production. A resting spore such as that of Nostoc thus provides for the future. An improvement upon this simplest type of resting spore is the zygospore in which two protoplasts co-operate to form a single, relatively large cell, well protected and richly stored with food for use at the time of germination. Even in the most primitive cases of co-operative provision for the welfare of offspring, a far-reaching 512 LIFE-HISTORIES advantage probably results from the union of different protoplasts. Much research in recent times warrants the belief that the offspring of two parents is benefited by the interaction of the slightly dif- ferent powers inherited from either side. Invigoration of the off- spring and increased adaptability are often plainly shown. Within s])ecific limits, the beneficial effect of a cro.s.s, as the union of gametes from different individuals is called, has been found to be greater as the parents are less alike or have lived imder more dissimilar condi- tions. Hence plants which can co-operate in the production of off- spring while living somewhat apart, make the most successful parents. Traveling gametes, as in Ulothrix, enable them to do this. But in order to travel well a gamete must be comparatively small, and when this is true of both gametes as in Ulothrix, the resulting zygote cannot be large or very well provided with food, and is there- fore at a disadvantage in becoming a resting zygospore. Here then is an opportunity for a useful division of labor in co-operative repro- duction. Let one of the gametes remain small for traveling, and let the other become as large and as well stored with food as possible, then the result of their union will be a cross-fertilized zygote of superior capabilities. The fact that the most highly developed groups of algse, notably the higher Chlorophyccte and the Rhodo- phycese, have adopted this expedient indicates that the experiment has been a great success among thallophytes where^"er it could be fairly tried. Along with the possibility of cross-fertilization is apt to go also the possibility of union between gametes from the same individual. This is distinguished as close-fertilization. It is better than no fertilization at all, but seems scarcely more beneficial to off- spring than non-sexual reproduction. Where both gametes are set free, about the best that can be done is the formation of such zygotes as we find in Fucus, where the off- spring receives no further care after fertilization has taken place. When, on the other hand, as in Coleocha^te, only the male gamete is set free, the female plant gains the opportunity to act as a nurse to its offspring, giving it additional protection and sometimes food after fertilization until it is well able to take care of itself. This nursing may so affect the development of the offspring that it becomes strikingly different from the form which bears it; then we have an alternation of generations. It is in this new development, which represents the highest achievement of thallo])hytes in their care of offspring, that we shall find potentialities of the utmost importance for the further development of plants. Fungi, especially non-aquatic forms, have generally degenerated so far as to lose any power of fertilization they may once have had. This may be because in the more or less isolated situations thej' usually occupy, co-operative reproduction seldom is possible; and another imjiortant reason may be that their dependence upon ready made food throughout life makes invigoration and nursing THE LIVERWORTS OR HEPATICS 513 of offspring less important for the w(>lfaro of the species than rapid and prohfic midtiplication. 189. The liverworts or hepv^tics (Class Hepaticae) take their name from a fancied resemblance of the broad-Iolied thalliis of certain lower forms to the lobed liver of an animal. iyk. jr Fig. 338. — Crystal worts {Riccui spp., Crystal wort Family, Ricciacece). A-C, R. Bischoffii; A, B, clumps of the plant growing on mud, (§) a, male plant; b, female plant. C, male plant, enlarged, showing the male gametangia or anthcridia (a). D-H, R. minima. D, plants (|). E, fruiting plant enlarged, top view. F, a lobe, side view. G, a fruiting lobe, cut vertically through the young "fruit" or sporophyte, still more enlarged. //, spore-groups and spores. J-M, R.glauca. J, iv, plants (§). L, M, lobes, enlarged. N, O, R. ciliata. N, two plants (5). 0, lobes, enlarged. PS, R. canaliculata. P, plant (i). 0, fruiting lobes, en- larged, top view. R, same, under side. S, lobe cut vertically through the sporophyte. (Bischoff.) — -Plants growing in moist places. There are al30ut 3,000 species in the group. The most primitive liverworts belong to the group known as crystal- worts, occurring in all parts of the world and including many species. Some of these grow floating on the surface of still, fresh water and finally come to lie upon the mud when the water subsides in dry seasons. Other forms grow 514 LIFE-HISTORIES more upon moist oarth or rocks; in these the thallus shows the broad hver-hke lobing especially well, and often appears as a flat rosette (Fig. 338, A, B). The more aquatic forms have narrow, much-branched, ribbon-like lobes (P, Q, R), and bear a striking resemblance to such algae as carrageen, while the forms with disk-like thallus (./, K), are closely similar to forms of sheath-algae. In both crystalworts and sheath-algae a lobe elongates by the continued division of a single terminal cell, which by its occasional forking gives rise to similar branches. Compare Fig. 314 with Fig. 338, P. One consequence of this continuous terminal growth and branch- ing is that when the older parts die and decay the newer parts are distinct plants which have thus arisen bj- a sort of vegetative re- production. No swarm-spores are produced, but the thallus often propagates non-sexually by single mature cells in various parts of the thallus dividing like a terminal cell and so producing a tiny bud or brood-body which, separating, becomes a distinct plant. The main structural difference between the alga and the liverwort- thallus is a somewhat more advanced differentiation of the latter. As the cells of Riccia grow older they maj' give rise on the lower surface to filamentous pseudo-roots and sometimes scale-like or tongue-like pseudo-leaves, while at the upper surface they may form a firm protective layer. Gamctangia arise on the upper surface as in Coleocha'tc but soon l^ecome immersed in the thallus through the growth of surrounding cells. Although strictly homologous with the gametangia of C'oleochicte those of the liverwort are some- what more elaborate in structure. The male gametangium (Fig. 339, A-D) includes a number of cells producing motile gametes each hav- ing two flagella like the male gametes of Coleocha'te and differing from them chiefly in having a more slender body. The female gametangium {E, a") is a flask-shaped multicellular organ containing a single female gamete. A female gametangium thus constructed is distinguished as an archegonium,^ the female gamete being called an egg-cell. In some cases both male and female gametangia are borne on the same thallus, that is to say. the thallus is bi-^^exual; while in other cases, a thallus has but one kind of gametangium, making it thus unisexunl. In the bisexual plants close-fertilization can doubtless occur; while in the unisexual, only cross-hn'tilization is possible. Fertilization is effected by a single male gamete, which because of its slender form is ai)le to make its way down the pro- jecting neck of the archegonium to the egg-cell. The zygote be- comes surrounded by a cellulose v.^all, and through repeated division forms a spherical mass of cells which at first are all much alike. This mass is a rudimentary sporoph,vte or embryo. The inner 1 Ar-che-go'ni-um < Gr. arche, first; gonos, generation. THE LIVERWORTS OR HEPATI(;S 515 cells each divide into four spores, while the outer cells become some- what thickened to form a protective case or capsule (Fig. 338 Q, K, S). At the same time the basal part of the archegonium grows apace and may become so thickened as to give additional protection to the spores over the winter. When thus developed it is termed a cab/p- tra.^ The spores are set free in spring by the breaking down of the coverings al)0ut them, and they germinate by producing a row of cells of which the apical one finally develops a thallus like that already described. We have thus in Riccia quite as evident an alternation of generations as we found in Coleocha;te, both the gametophyte and the sporophyte being somewhat more highly de- veloped. Fig. 339. — Crystahvorts. A-C\ Riccia glaiica ("l'^): A, young antheridium; st, stalk. B, same, older. C, same, still older, showing the many cells, in which motile gametes (spcrmatozoids) are produced. D, ripe an- theridium of R. minima {>-\-)\ e, outer cells of thallus; I, air-spaces. E, R. ciiiata ("i'"-), growing-tip cut vertically to show the terminal cell (s) which by its successive divisions produces all the rest of the plant, the pseudo-leaves (b'-b"") which project from the lower surface of the thallus and hold water for it, and archcgonia, very young (a') and full grown (a"), ready for fertilization. (Waldner, Kny.) Both generations are still more highly developed in the umbrella- liverwort (Marchantia, Figs. 340-342), a common species growing on the earth in moist localities. The spores germinate much as in Riccia, but the thalli are always bisexual. At hrst, however, both forms are essentially alike and resemble a brood-lobed Riccia. From the under side arise numerous unicellular i)seudo-roots and many scale-like pseudo-leaves. On the upper surface are often formed numerous brood-bodies of the form shown in Fig. 342, wdiich are produced at the bottom of little cups the whole suggesting a minia- ture nest full of eggs. By this peculiar form of vegetative reproduc- tion the gametophyte is rapidly multiplied; for as soon as a brood- 1 Ca-lyp'tra < Gr. kalyptra, a veil. 516 LIFE-HISTORIES Fig. 340, I. — Unibiella-liverwort {Marchantia polymorpha, Umbrella- liverwort Family, Marchantiacew). Male plant bearing antheridia- carriers (antheridiophores) |. (Atkinson.) — The plant is common on moist earth, rocks, etc., throughout the world. Fig. 340, II. — Umbrella-liverwort. Top of antheridiophore (,), cut ver- tically to show the cavities containing antheridia. (Atkinson.) body is carried away by some current of rain water and comes to rest in a favorable spot it sends out pseudo-roots from whictiever surface happens to be undermost, and begins to grow into a new thallus. After a while organs distinctive of the sex appear near the growing end, and curving upward become differentiated into a cylindrical stalk and an expanded top. In male plants (Fig. 340 I-IV) this top is a lobed disk on the upper side of which are pits, each containing a multicellular gametangium, from which come slender motile gametes like those of Riccia already described. Archcgonia arise also on the top of what is at first a somewhat similar THE LIVERWORTS OR HEPATICS 517 Fig. 340, III. — Umbrella-liverwort. Antheridium (V) showing the numer- ous cells within which produce spermatozoids. (Atkinson.) Fig. 340, IV. — Umbrella-liverwort. Spermatozoids, highly magnified. (Atkinson.) expansion (Fig. 341, I-V), but they come finally to lie underneath through the folding downward of the edges of the lobes. The female gametangia are thus protected by their position, and besides this they are covered by a hanging curtain (Fig. 3-41, V, p). When the plants are wet with rain or dew the flagellate male gametes are set free and swim or crawl from their elevated home down the stalk and to a female plant ; then they climb up its stalk (doubtless aided by numerous hairs thereon) to the archegonia. The fer- tilized egg-cell gives rise to a spheroidal embryo which develops into a sporophyte resembling that of Riccia for a while but finally, by growth of the basal region of the capsule, producing a foot- stalk whose elongation pushes the sporangium through the top of the calyptra (Fig. 341, III). Meanwhile, elongated cells, called elaters i (Fig. 341, IV), having elastic, spirally thickened walls are being formed among the spores; and when finally the cap- sule bursts open these elaters, by mechanical movements due to drying, eject the spores and so help to scatter them. The sporo- phyte is fed entirely by the gametophyte and lives as a parasite, the foot or lower end of the stalk serving as an haustorium. Especial interest attaches to the genus Anthoceros (often called horned liverworts from the form of the sporophyte), because these humble plants have preserved structures which help us to under- stand how all the higher plants may have originated. The game- 1 E-la'ter < Gr. elaler, a driver. 518 LIFE-HISTORIES Fig. 341, I. — Umbrella-liverwort. Female plant (i), bearing archegonia- carriers {archegoniophores) . (Atkinson.) tophyte develops from a spore in much the same way as happens with the other Uverworts described. Even more than in Riccia it is hke the thallus of Coleochsete, notably in jiossessing but a single chromatophore in each cell, and in having no trace of pseudo-leaves (Fig. 343). The gametangia are completely embedded in the thallus (Fig. 344). The embryo (E) develops a somewhat expanded foot which serves to hold the slender sporophyte in an upright position, and functions also as an organ of absorption. As the sporophyte continues to grow, however, it is plain that scarcely more than inorganic materials are taken in; for very soon, above the foot ap- pears an elongating zone of tissue containing much chlorophyll; and this enables the sporophyte to photosynthcsizc and so, unlike our other liverworts, to be almost self-supporting. If an Anthero- ceros sporophyte should ever develop a root it would no longer need to be even a partial jjarasite, as now, but could lead an entirely independent existence. The elongating region connecting the cap- sule and the foot is morphologically a shoot, and thus we have in this little plant the beginnings of a differentiation into three mem- bers— sporangium, foot, and shoot. At the center of the shoot and THE TRUE MOSSES 519 341, II. — Umbrella-liverwort. ArchiKonio- phores (?) bearing ripe "fruit" (sporophytes), the spore-cases of which aie seen projecting beyond the curtains wliich protected them while young. Two of the spore-cases have burst showing the projecting elaters. (At- kinson.) extending into the capsule is a column of somewhat elongated cells, which is called the columella ' (Fig. 345, c, c). Breathing-pores at the surface permit aeration of the inner cells. Hepatica^ are plants producing archegonia upon a mostly prostrate and thalline gametophyte which may he variously lobed or branched and often resembles a flattened leafy moss, but which generally has well-contrasted upper and loiver surfaces; and there is a sporangium geyierally dehiscing longitudinally and discharging its spores by means of intermingled thread-like elaters. There are about 3,000 species. 190. The true mosses (Class Musci). The name "moss" is popularly given to any small, matted plant of soft texture ^ Col-u-mol'la < L. diminutive of colnmna, a pillar. 520 LIFE-HISTORIES Fig. 341, III. — Umbrella-liverwort. Top of archigoniophore (t) cut ver- tically to show the stalked sporophytes of different ages: the two inner ones are still within the enlarged wall of the archegoniuni ; the right- hand one has protruded on its stalk leaving the archegonial wall as a sheath (calyplra) at the base of its stalk; while the left-hand one has burst open and is shedding its spores and elaters. (Atkinson.) Fig. .341, IV. — Umbrellarliverwort. nic, cluster of young spores; sp, spore. An elater. A piece of the same, showing the clastic spring-like spiral thickening within. All highly magnified. (Atkinson.) THE TRUE MOSSES 521 Fig. 341, V. — Umbrella-liverwort. Archegonium (at the left) containing an egg-cell (e) : and (at the right) the same, later, containing a young sporophyte (sp). ^;*'- The neck (n) of the archegonium, and its base (v), are shown in both; as also the protective curtain (p). (Atkinson.) .-^'^^ #^ Fig. 342.^Umbrella-livcrwort. Thallus (;) showing on the top seven brood- cups containing minute brood-bodies; and below numerous pseudo-roots. (Atkinson.) x 522 LIFE-HISTORIES whether it be a seaweed, a Uchen, a Uverwort, or one of the higher phints. In strictest l^otanical use it belongs only to about 5,000 species of small green plants which have pseudo- leaves usually arranged spirally on a pseudo-stem, and pro- duce spores in urn-like cases opening mostly by a lid. Fig. 343. — Horned-liverwort (Anthoceros 1(fv{s, Horucd-livorwort Family, Anthocerotacco') . Plant (i) with three "fruits" (sporophytes). (Luers- sen.) — Rather common in moist soil. Fig. 344. — Horned-liverwort. A, branched thallus. B, thallus (V) cut vertically to show the antheridia {an), the pseudo-roots (w), and a colony of Nostoc {k) which sometimes lives in the interior of this plant. C, vertical section through tip of thallus {^\^) showing beginnings of archegonia {ar). D, section through older part of thallus ('5"), show- ing a fertilized archegonium in which the egg-cell has begun to divide. E, embryo of sporophyte showing shoot-part above and foot below. (Hofmeister.) True mosses resemble liverworts except in having a mostly erect gametophyle with pseicdo-leares spiraUy disposed about a pseudo- stem which supports a sporangium dehiscing by a lid and lacking ola- ters. These peculiarities are sliown in the peat moss (Sphagnum, Figs. 227, 346-349) and the cord moss (Funaria, Figs. 350-356). The spores of Sphagnum (Fig. 346) germinate in water by send- ing out a branched thread which resembles a filamentous alga. Sooner or later this tlu'ead gives rise at several points to apical c(>lls each of which by its frequent oblique divisions produces a i)seu{lo- stem with pseudo-leaves. If, however, tlic spore falls upon moist earth, its germination is more. like such a liverwort as Anthoceros or Marchantia, for the initial thread soon develops into a flat- lobed thallus, producing slender pseudo-roots below, and vertical THE TRUE MOSSES 523 Fig. 345. — Horned-liverwort. Young sporophyte (fig, scj) showing the be- ginning.s of a columella (c, c) and spores (s). L, L, calyptra, •ij'^. (Hofmeister.) Fig. 346. — Peat moss (Sphagnum acutifolium, Peat moss Family, Sphagna- cew). A, spore, highly magnified. C, spore (s) germinating in water producing a green branched thread or protonema (n, n') from which buds (pr, pr) arise and produce gametophytes. (Schimper.) — Plant common in bogs. Fig. 347. — Peat moss. Flat pro- tonema (pr, pr) produced on moist earth, giv- ing r i s e to a gametophyte(7«) and pseudo-roots (u'),>-i». (Schimp- er.) 524 LIFE-HISTORIES Fig. 348. — Peat mosses. ,4, part of a ganietophyte, enlarged, showing male branches (a, a, n, a) and female branches {h, h). B, part of a leaf (S. cymbifolium), ajft, showing the not-work of green cells surrounding the large ones which fill with water or air. C, vertical section through a small piece of leaf (S. cuspidatum) showing the small and the large perforated cells, 'i". D, cross-section through outer part of stem (S. cymbifolium) highly magnified. E, male branch of S. acxdifoliwn, ■with a vegetative branch at the base, Y. P^ same, with many pseudo- leaves removed to show the male gametangia {antheridia), '•^i. G, an opened and empty antheridium, -f«. H, five cells containing young spermatozoids, ■>■?«. J, such a cell nearly ripe, ■ija. K, spermatozoid, ^<'-. L, ripe "fruit" (sporophytc) with remains of the archegonium at its base borne on a stalk continuing the axis of the pseudo-stem which bears pseudo-leaves at its base; magnified. (Schimper.) THE TRUE MOSSES 525 moss-branches above (Fig. 347). In either case these vertical pseudo- leafy shoots are homologous \A-ith the ascending branches of ^lar- chantia; but as seen in Fig. 348 they are much more elaborately constructed. At the surface of the stem are developed usually several laj^ers of large cells with very thin walls which are kept from collapsing by ridge-like thickenings, and communicate with one another and with the exterior by pores (D) of considerable size. These cells soon lose their protoplasm and then form a sponge-like Fig. 349. — Peat mosses. A, tip of female branch of S. acutifolium, cut vertically to show the archegonia {ar), protective leaves {ch) still j'oung, and older ones {y) acting like bud-scales. B, young "fruit," cut vertically to show the sporophyte of which the foot {sg') is fixed in the head (r) of the stalk or pseudopodium (;;s), and the spore-case (sg) IS still enveloped by the calyptra (c) bearing above the old neck (ar) of the archcgonium. C, ripe sporophyte of .S. squarrosum, showing its lid id) and spore-case {sg) emerged from the torn calyptra (c) and borne upon a pseudopodium pushing it beyond the formerly protecting pseudo-leaves {ch). All magnified. (Schimper.) or wick-like envelope which draws water from below by capillarity, and stores it ready for use. The pseudo-stem is streng-thened by a uniform thickenmg of the walls of an inner cylinder of cells. The pseudo-leaves are made up chiefly of large, thin-walled cells {B) like the outer cells of the pseudo-stem, similarly reinforced by ridges and similarly perforated. They supply water to a net-work of small cells containing numerous chromatophores in which the work of photosynthesis is carried on. Vegetative reproduction so far as known takes place only through the separation of branches 526 LIFE-HISTORIES by decay of the older part. Male gametangia (F) are borne on the side of special branches which may be recognized as having their leaves more crowded and often reddish (A and E). The numerous male gametes (K) are more elongated and more spiral than those of Marchantia, but are otherwise similar. Archegonia are produced at the tip of short branches surrounded by comparatively large leaves (Fig. 349, .4). After the female gamete has been fertilized, the axis of the branch elongates into a stalk bearing at its tip the enlarging sporophyte enveloped in the calyptra {B, C). The sporo- phyte is differentiated into a short, thick foot {sg') and a capsule in which there is a central mass of large air-filled cells surmounted by Fig. 350. — Cord-mos.-s {Funaria hygrornetrica, Cord-moss Family, [''unan'd- cece). A, germinating spore {^\^) showing a sap-filled cavity or vaouolo (v) a pseudo-root (w, w), and the old outer spore-wall (s). B, further development of the thread (protonema) which comes from the spore, showing the main thread {h) and side branches from one of which {h) is growing a bud [K) destined to form a pseudo-stem and pseudo- leaves, and already sending out a pseudo-root («')> ^i"- (Sachs.) a hollow dome-like mass of spores, and the whole inclosed in a firm wall of small, hardened cells. A horizontal ring of these becomes finally so brittle as to render the top of the capsule scparal^le like a lid (C, d). As the capsule enlarges, the calyptra (c) is ruptured, and as the spore-case dries its form changes perceptibly from spherical to subcylindrical but without elongation. The result is that the inner air-filled cells below the spore-mass are so much compressed, that a degree of tension is soon reached sufficient to blow off the lid with a perceptible report and scatter the spores to a distance of several inches. Elaters are thus unnecessary. In Funaria (Figs. 350-356) the spores when germinating (Pig. 350) produce a much-branched thread which mak(>s a bright green, felt- like layer on moist earth. From this thread at many places arise directly vertical pseudo-shoots each consisting of an axis bearing THE TRUE MOSSES 527 /^'(^o ,1(5^ B 0 p0' Fig. 351. — Cord-moss. Tip of a male gametophyte cut vertically to show the male gamctangia (antheridia) of various ages from young (a) to almo.st full-grown (6); also paraphyse (c), protective pseudo-leaves (d) and fi)liag(' p.si'udo-leaves (e), "5". (Sachs.) Fig. 352. — Cord-moss. .4., anthcridium discharging its spermatozoids («), aftt. B, b, spermatozoid not yet escaped from its cell-wall; c, the same swimming freely, a^«. (Sachs.) delicate pseudo-roots from the lower part, pseudo-leaves arranged spirally along the sides, and at the tip either male or female gamc- tangia (Figs. 351-353). The gametophj^te in Funaria is thus of somewhat simpler constitution than in Sphagnum. The cellular structure also shows less differentiation. On the other hand, the sporophyte is more complex. As shown in Figs. 354, 355 the foot becomes a long stalk, and the capsule develops several different tissues. The calyptra ruptures transversely at the base and is cai- ried up on the capsule as a hood which falls off after the capsule is mature. A cylindrical spore-layer surrounds an inner mass of cells and certain inner cells of the lid break so as to leave behind on the capsule after dehiscence a fringe of teeth, called the peristome' Its function is to protect the spores and keep them from being blown out by a light breeze which would carry them only a short distance. 1 Per'i-stome < Gr. peri, around; stoma, mouth. 528 LIFE-HISTORIES Tn dry weather, after calyptra and lid have fallen, a strong wind will shake the capsule on its slender elastic foot-stalk, and scatter the spores out between the teeth. The most remarkal)le difference between the sporophytes of Funaria and Sphagnum is that the former like that of Anthoceros contains chlorophyll and is thus able Fig. 353. — Cord-moss. A, tip of a fenialo ganictophytc cut vortirally to show the female gametangia (archogoiiia) surrounded by pseudo-leaves (b), ^^. B, an archegonium showing the swollen lower part (b) con- taining an unfertilized egg-cell, the neck (h) with its orifice (/«) still closed and the axial row of cells being converted into mucilage, *?«. C, orifice of an archegonium after fertilization, with its cell-walls colored dark red, ^-'l^-. (Sachs.) Fig. 354. — Cord-moss. A, embryo of sporophyte (/,/') still within the arche- gonium (h, h), cut vertically, h, Ijcing the neck, ^^-. B, C, more ad- vanced stages in the tlcvelopment of the sporophyte (/) covered by the old archegonium or calyptra (r) ui)on which the neck (h) still remains, Y- (Sachs.) to manufacture a large part of its own footl while the latter is like the sporophytes of Riccia and Marchantia in being entirely para- sitic upon the gametophyte. Inorganic materials alasorbed by the slender pseudo-roots of the gametophyte are supplied to the foot of the stalk and thence conducted to the photosynthetic tissue of the capsule. Conduction take places mainly through a central THE TRUE MOSSES 529 Fig. 355. — Cord-moss. .1, female gametophyte bearing pseudo-leaves (g) and a calyptra (c) still protecting a young sporophyte, J. B, same, at a later stage when the calyptra (c) has been carried up as a hood on top of the spore-case (/) by the elongation of the stalk (s) of the sporophyte, I. C, spore-case or capsule, enlarged and cut vertically to show the lid (d), a connecting row of cells, the armulus (a), a row of projections, the peristome (p) covering the mouth, a central mass of cells, the columella (c, c), air spaces (h), and the layer of spores (s), !. (Sachs.) Fig. 356. — Cord-moss. A, spore-case, showing peristome and twisted stalk. B, cells of the annulus. C, breathing-pores (stomata). D, teeth of the peristome. E, spore-case cut vertically, F, young spore-case still covered by the calyptra. Variously magnified. (Baillon.) — Common on waste or barren soil. 530 L1FE-I1I8T0KIES cylinder which consists of cells elongated in the direction of the axis and with pointed ends which interlock. Such a tissue is termed prosenchynia ' in contrast with pareuchyina 2 which is composed of cells not much elongated, and without pointed ends, as is the case with nearly all the tissues we have so far studied. At the surface of the sporophyte is a protective layer of cells, distinguished as the epidermis; 3 the looser, mostly green tissue which lies between the epidermis and the central cylinder being termed the cortex J In the epidermis near the base of the capsule occur peculiar openings called stomata ^ communicating with the internal air-spaces of the cortex. Each opening is guarded by two special cells which might be likened to lips. It is by means of these breathing pores that the interior tissues are aerated. Whereas in the sporophj^te of Sphagnum we have a very simple sporangium from which there is differentiated a small foot and the merest hint of a short connecting stem ; in Fu- naria we find a long slender stalk, homologous with the foot, bearing a capsule made up of the sporangium partly inclosed by an urn-like mass of tissue which we may call the shoot. Funaria represents about as high development of the sporophyte as moss plants have ever attained. 191. The bryophyte division, mossworts (Bryophyta) comprises only the two classes liverworts (Hepaticae) and true mosses (Musci) which in general are often called moss- worts. Mossworts show us possibly how green earth-plants first stood upright. The occasion for their vertical development may have arisen when certain flat algffi more or less like Coleochaete, became stranded and had to form spore-cases as best they could before the mud completely dried. If some of them were able to make a small globular capsule this might be fed entirely by the thallus, but being immersed within it could not ordinarily scatter the spores very far. Their descendants perhaps give us Riccia. Others we may suppose, hit upon the plan of elongating the capsule upward, giving it some chlorophyll to utilize the sunshine, and thus enable it to make more spores and scatter them farther — all with much less dependence upon the slender resources of the little nurse. The result would be a liverwort of the Anthoccros type which solves the problem of uj)- lifting its spores in the simplest way. Various more or less com- ^ Pros-en 'chy-ma< Gr. pros, before; en, in; cheo, pour. ^ Par-en'chy-ma < CJr. para, beside. A term applied by the earlier anatomists to the main tissue of sueh organs as the lungs which they supposed was formed of material poured in beside tlie vessels and nerves that had been " poured in " before. ' Ep-i-dcr'mis < Gr. epi, upon, t. e., outer; derma, skin. * Cor'tex < L. cortex, rind or bark. ^Sto'ma< Gr. .s7o/««, a mouth. BRYOPHYTE DIVISION, MOSSWORTS 531 plicated expedients were adopted by plants akin, and the outcome is seen in such liverworts as Marchantia where small capsules are made to hang from the branches of vertical thallus-lobes, or in mosses like Sphagnum where a similar though erect capsule is borne on an even more elaborately developed vertical branch of the nurse- plant, which may live for many years. The most complicated ways of securing elevation are found in the mosses typified by Funaria, where both the nurse-plant and the spore-plant develop vertically as far as they can — the latter, as it were, standing upon the shoulders of the former — and by photosynthesis making food for the spores. But the utmost height attained by these methods is only a few inches; the foundation is weak. Growth which has to be accom- plished during a short season of moisture or by improving brief periods of wet weather, must naturally for the most part be limited to rather soft tissue and small organs. IMosses often grow crowded together like Sphagnum and thereby give mutual support and store a supply of water for use in common; but although axes of considerable height may be built in this way, the offspring is not much benefited, for the crowded tops of the axes form virtually a new surface above which is the only height effective for scattering the spores. It is plain that effectiveness is not always favored by complexity. The view suggested above that mossworts have evolved direct!}^ from algte akin to Coleocha^te, although regarded as probable by many botanists, receives no support from the study of fossil plants; and is by no means the only view consistent with what is known of the plants of to-day. Thus, it is ciuite possible that our mossworts may be the more or less simplified descendants of larger plants widely different from any we know, which themselves were de- scended from seaweeds very unlike Colechsete and of which we have now no trace. Not a few facts point to this conclusion ; but the truth is we are much at a loss as to what to believe regarding the origin of mossworts, and the question seems likely to remain long a puzzle. Meanwhile, the hypothesis of direct algal origin may help us to imagine something of the nature of the prol:)lems which had to be faced by the earliest land-plants, whatever these plants may have been; and may suggest, at least by analogy, something of the means that may have proved most effective. When we remember that Bryophytes have had to depend almost entirely upon superficial moisture it is not a little remarkable how much they have been able to accomplish for the welfare of their offspring. In spite of serious difficulties attending the use on land of reproductive arrangements adapted to aquatic life, the.se little plants very commonly achieve the benefits of cross-fertilization, and of a considerable period of nursing for their young. All this is made possible by the formation of archegonia which not only pro- tect the protoplast of the egg, but by further development shield the young spore-plant all through its time of special tenderness. 532 LIFE-HISTORIES Finally, in a considerable variet}- of ways means are provided for scattering the spores as far as possible and under the most favorable conditions for giving the new plants a good fair start. Bryophyta are disli)iguished by having archegonia on lobed or pseudo- leafy gametophyles which bear sporophytes lacking true roots, stems, and leaves. Fig. 357. — -Adder-tongue, A, and grape-fcrn, B {O phioglossum vulgatum and Botrychium Lunaria, Adder-tongue Family, Ophioglossacew). Sporophytes showing roots (w). stem (st), leaf-stalk (hs), point (x) at which leaves branch to form a foliage-blade (h) and a spore-bearing division (/). Two-thirds natural size. (Sachs.) — Not very common but widely distributed in mostly open ground. 192. The ferns (Class Filicinae). Our most primitive ferns are represented by adder-tongues (Ophioglossum) and grape-ferns (Botrychium, Fig. 357). Unfortunately their life-histories are not yet fully known owing to peculiar difficulties in tracing the germination of the spores. The gametophyte is sul)terrancan (Fig. 358) and at least when mature it is saprophytic. Except for its lack of chlorophyll it is not a little like the gametophyte of Riccia. The gametophyte of THE FERNS 533 certain ferns closely related to tlie aliovc more nearly resembles that of Anthoceros, and is holophytic, as we may suppose to have been the case with the orif>;inal feru-ancestor. When we compare the sporophytes of an adder-tongue and a horned liverwort, how- ever, so many striking differences appear, that it may at first seem hopeless to think of homologizing the parts? Indeed, we have in ferns true leaves, stems, and roots, no trace of which appear in any liverwort. But we have sporangia in both, and in the growing zone of Anthoceros we have a cjdindrical meristematic organ suggesting possibilities of much further differentiation. If the sporangium of Fig. .358. — -Grape-fern. A, gametophyte (prothallus) cut vertically to show the antheridia (an), the archegonia {ac), and the pseudo-roots (w), ^{'-. B, lower part of a young sporophyte dug up in September, cut vertically to show the stem (si) and leaves (b, b', b"), 'f. (Hofmeister.) Fig. 3.59. — -Adder-tongue. Upper part of spore-bearing division of leaf ("), cut vertically to show the tip (s), the spore-cavities (.sp), the places (r) where a slit is formed to free the spores, and the woody strands or fibro- vascular burulles (g) which strengthen and conduct sap. (Sachs.) Anthoceros were enlarged and instead of elaters produced sterile tissue between groups of spores forming two rows on either side of the columella, the resulting organ would be a flat spike of sporangia like that of Ophioglossum (Fig. 359). What may have happened is that in very ancient times, before the age when coal plants flour- ished, a liverwort something like an Anthoceros did evolve a root from the lower end of its growing zone, which made possible an expansion of the green tissue above, while this in turn helped to bring about the formation of two rows of globular sporangia making a flat cluster as already described. Such an expanded member 534 LIFE-HISTORIES bearing sporangia would be a spore-sac-leaf, while the cylindrical elongating zone from which it arose would now be a true stem. Here would be about as simple a fern as we can imagine; but it would have all the essential features, and it is not inconceivable that higher forms might have been evolved from it. Suppose, for instance, that the sadeaf member forked into two branches, and let one of them be expanded so as to secure as much sunlight as possible and be devoted exclusively to photosynthesis, while the other branch instead of doing much food-making was narrower and developed as many spores as possible from foocl that the expanded branch furnished. Suppose further that the stem lived on from year to year, sending new roots into the earth and new leaves into the air, then our plant would have become like an adder-tongue fern. The striking differences between liverworts and ferns of any kind have so imjoressed not a few botanists as to have made them doubt the likelihood of ferns having originated in the manner above suggested; and this doubt has gained strength from the fact that the most ancient fossil ferns are of highly complex organization, being often tree-like in form, and so even less like liverworts than the presumably degenerate ferns with which we are most familiar to-day. Moreover, if modern liverworts are also to be regarded as degenerate plants — a view, as we have seen, for which there is some evidence — the gap which separates them from ferns is even wider. It may well be true that ferns evolved directly from sea- weeds in which a clearly marked alternation of generations had developed as in certain rather highly organized red alga^ living to-day. On this supposition, however, we are still left with the difficulty of imagining the stages through which a seaweed could pass in fitting itself for life on land as a tree. Here fossils cannot help us, for we have none at all intermediate between seaweeds and ferns. Since, however, there are undoubted fundamental re- semblances between a Coleochsete, an Anthoceros, and an Ophio- glossum, these may offer at least a possible clue as to how the great changes in question may have taken place. Grape-ferns would be readily derivable from adder-tongues by further branching of the two leaf branches, which in the fertile or sporangial segment might result in each sporangium being borne on a little stalk or branchlet of its own. We may well imagine that wonderful possibilities of development lay before such a type as this as soon as it established itself on the edges of swamps or on land where food and moisture abounded. It could then afford to delay the production of spores imtil it had built a thick, tall stem, by means of leaves made larger and larger year after year and devoted entirely to making food so that a surplus might be stored in the stem. Finally, a very large number of sporangia might be produced upon much-branched spore-sac-leaves; and these, held high in the air, could scatter their spores most effectively. THE FERNS 535 We know tliat during the coal age many trcc-tVrns like the Pecopteris shown in Fig. 277 (page 299), apparently near of kin to the adder-tongues, produced stout trunks bearing a crown of ample leaves nearly twenty meters above the ground. (^^^ Fig. 360.— Tree-Ferns and Herbaceous Ferns. (Baillon.) At the present day tree-ferns such as tlie one shown in Fig. 360 abound in moist, warm regions, although the ferns most common in northern lands are more like the smaller ones shown in the same illustration. Thus it would appear that a certain amount of degeneration has attended the adaptation of ferns to the more stringent conditions of cold 536 LIFE-HISTORIES Fig. 361. — Male-fern (see also Fig. 170). a, b, germination of spores show- ing formation of young gametophytes (prothallia), "i". (Luerssen.) Fig. 362. — Male-fern. .-1, prothallus, lower side, showing archegonia {ar), antheridia (an), and pseudo-roots (rh). ?. B, same, after production of young sporophyte, showing first leaf {h) and first root (w). (Schenck.) or dry climates. One of our best developed northern ferns is the Aspidium already studied (Fig. 170, page 179). As shown in Figs. 361, 362, the spore in germinating produces first a row of cells, the terminal one of which soon divides in such a way as to produce a flat, heart-shaped thallus, which is rich in chlorophyll and sends out from the under side of the older part a number of pseudo-roots. B}^ means of these the rear end is firmly attached to the earth while the lobed end slightly ascends. Finally on the lower surface appear archegonia near the tip, and male gametangia toward the base. The latter and their motile gametes are of the form shown in Fig. 363. The gametes, it will be noticed, are somewhat more highly develoj^ed than any found among the Bryophyta. That is to say, the spiral is larger and the flagella are more numerous. The archegonia, which are like the one shown in Fig. 364, differ but little from the others already studied. After fertilization the egg-cell divides into four (Fig. 365, A). The upper- most of these, by its further growth and division produces the foot (/) the function of which is to act temporarily as an haustorium for the embiyo-sporophyte, and to push it out of the gametophyte and on to the earth. One of the lateral cells dex'elops into the first root (iv) while the opposite one becomes the growing point of the stem, and THE FERNS 537 the lowest cell gives rise to the first leaf. A later stage in the de- velopment of these parts is shown in Fig. 365, B. Covering the growing tip of the root, somewhat as a thimble covers a finger tip, is a protective organ termed the root-cap. Such a thimble-like cover- ing continually renewed by the meristem which it protects is char- acteristic of true roots. Root-hairs for absorption are soon devel- oped. The leaf (Figs. 365, B, 362, B) soon differentiates into petiole and blade, and curves so as to drag the tender leaf-tip up out of the ground. An extreme curving of this nature performed by every ^ '^S^K^MfM Fig. 363. — Fern Antheridium {Pteris sp., Polypody Family, Polypodiacew), ^l". (Luersscn.) Fig. 364. — Fern Archcgonium {Osmunda sp., Royal-fern Family, Osmuyida- cem). A, first stage viewed from above, -Y. B, same, cut vertically to show the central cell (c) from which the egg is formed, and the cells {h) which give rise to the neck, '-;!>. C-E, older stages, showing canal cells (^c, 6c). /^, neck with mouth closed. G, same, top view. //, same, mouth open. J, same as E but with egg-cell (e) ready for fertilization. (Luerssen.) branch of the developing leaves gives us the familiar crozier-like vernation characteristic of ferns. In the axis of the stem soon ap- pears a central cylinder of prosenchyma which developing also in the root and the leaf serves as a channel for conducting solutions absorbed by the root to the green food-making parts of the leaf, and likewise dissolved nutrients from the leaves to the stem and the root where they may be used in growth or stored as a reserve. As the stem grows larger, and leaves and roots become more numer- ous, its central cylinder becomes a hollow cylindrical net-work of broad flat meshes (Fig. 366), giving off slender branches to the 538 LIFE-HISTORIES Fig. 365. — Fern Embryo (Pteris -sp.). A, embryo removed from archcgon- ium and cut verticallj- to show the first dividing wall (I, I) and the walls at right angles to this (II, II) whereby the fertilized egg-cell was divided into quadrants of which one (/) by further cell-division and growth becomes the foot, another (s) the stem, another (b) the first leaf, and another (w) the root. B, embryo still further developed but still attached to the prothallus (pr), cut vertically to show the foot (/) embedded in the archegonium (aw), the root (»•) with its tip protected by a root-cap, the stem (s) and the incurved leaf (6). Magnified. (Hofmeister.) leaves and roots. When a leaf falls off it leaves a scar upon which one may see clearh' traces of these slender branches which went into the petiole. In the trunk of a tree-fern (Fig. 367) the prosenchyma is par- ticularly well-developed and shows plainly a differentiation of tissues which is characteristic of all plants higher than br3'ophytes. Each strand is here found to contain thick-walled woody fibers (FB) and larger cells (VS) called vessels which have thin walls variously strengthened by ridges. These vessels correspond to the ''pores" found in the wood of oak and other trees we have already studied. Such strands are called fibrovascidar ' bundles, and the plants or parts containing them are said to be vascular. The ultimate branches of the framework of a leaf are often nothing but single vessels. Be- sides the woody and the vascular tissues, which serve mainh' for conducting fluids, ferns and higher plants often develop strands or layers of hardened, thick-walled cells whose function is mainl}' to give strength or afford protection. Such tissue is termed scleren- chijma - in general, or sclerotic parenchyma or prosenchj'ma in particular. An outer layer of the cortex as at {FL) often becomes sclerotic and thus contributes much additional strength to a co- hunnar organ. The parenchyma of a fern-stem serves very largeh' for the storage of reserve food in the form of .starch. From the epidermis of various parts may arise hair-like or scale-like out- growths which serve mainly to protect organs that are very young or especially need to be covered. Whereas in multicellular plants ' Fi'bro-vasVu-lar < L.fibra, a fiber; rasculum, a small vessel. - Scler-en'chy-ma < Gr. skleros, hard. THE FERNS 539 Fig. 366. — Fern Steins {Aspidium spp.). A, underground stem (rhizome) of .4. Filix-mas with rind removed to show the net-work of fibrovascular bundles. B, one mesh of this net-work enlarged to show the branches which enter a leaf to form its framework. C, cross-section of a rhizome {A. corioceum) slightly enlarged to show the cylindrical fibrovascular system formed of two main strands, the upper (o) smaller than the lower («), and the finer branches of these which enter the leaves. D, the fibrovascular cylinder of the same, removed and laid out fiat after splitting the lower strand (u, u) in halves, leaving the upper strand (o) in the middle unbroken, as also the finer strands (6, 6, h, h) which enter leaves and roots, and the larger strands (j, x, x, x, x) which enter branches of the stem. (Sachs, Mettenius.) of simpler structure it was sufficient to distinguish merely different tissues, in the higher plants the differentiation has progressed so far that tissue systems must be recognized. Thus we have a tegu- mentary system consisting of the epidermis and its outgrowths, a vascular systetn comprising the vascular bundles, and a fundamental system consisting mainly of parenchyma and includiBg meristem, the green cells accessible to light, and the pith-like internal parts in which food is stored. The stem of an Aspidium (Fig. 170) as of nearly all our native ferns, remains mostly underground as a more or less horizontal rhizome. A considerable amount of starch stored over the winter m the fundamental tissues of this perennial organ, accounts for the rapid unfolding of the leaves in spring. Some of the leaves are entirely vegetative; other leaves bear numerous minute sporangia in clusters upon the back, each cluster being covered by a shield- like out-growth (Figs. 170, 3-5). A peculiar part of the sporangium is a ring of thickened cells running along the back (6c), which when 540 LIFE-HISTORIES t'li V FV t li r L i L E Fig. 367. — Tree-Fern. Section of trunk. A wedge cut from the same, magnified to show the pith (P), a fibro vascular bundle (V F V) with its sclerenchyma (F B) and vessels (V S), and the rind (F L) and epidermis {E). (Baillon.) Fig. 368. — Fern Brood-bud {Aspidium Filix-mas) on base of leaf-stalk, 1. (Luerssen.) THE FERNS 541 Fig. 369. — Scouring-rush (Equisetum arveiise, Scouring-rush Family, EquisetacecE). 1, spore-bcaiing shoot with erect branches ending in cone-like clusters (a) of sporophylls or sporangia-bearing leaves. 2, vege- tative shoot, with underground stem bearing tubers (o) gorged with food. 3, a sporophyll with sporangia, enlarged. 4. same, showing sporangia split open after discharging the spores. 5, 6, 7, spores with "elaters" wrapping closely, or more or less spread. (Wossidlo.) — • Common in moist places. ripe suddenly straightens, so as to rupture the tliin wall in front and eject the spores. Sporangia of this tj'pe although differing in many ways from those of the adder-tongue and its kin, are doubtless homologous with them, for students of ferns find a very complete series of intermediate forms connecting the extremes. Vegetative 542 LIFE-HISTORIES reproduction is sometimes accomplished in ferns by the formation on various parts of buds which fall to the ground and take root (see Fig. 368). Filicina; in general agree with the ferns described in being arche- goniate, vascular plants, forming true roots and stems, and having alternate leaves upon which are borne sporangia that discharge their spores without elaters. The number of species is reckoned at about 3,000. 193. The scouring-rushes (Class Equisetinae) are repre- sented in modern times only by comparatively small plants of the genus Equisetum (Fig. 369) — about 25 species — which, however, are closely related to numerous gigantic rush-like coal plants, typified by the genus Calamites (Fig. 277, 2). In Equisetum cross-fertilization is accomplished by having male and female gametophytes which, as shown in Figs. 370, 371, differ considerably from one another, the female being much the larger and suggesting somewhat by its pseudo-leaves the nurse-plant of a moss. The sporophyte differs remarkably from that of any fern in the comparatively great development of the stem. This is hollow except at the nodes, and performs nearlj^ all the work of photosj'n- thesis. The roots do not differ essentially from those of ferns, but the foliage leaves are reduced to toothed sheaths serving chiefly to protect the tender regions of the stem. The fibro- vascular bundles of the stem are arranged in a ring, and in some forms (mostly extinct) a cambium like that of higher plants is develoi)ed which gives rise to successive rings of tissue. Such additional material by which increase in thick- ness is accomplished takes the name of secondary tissue, to distinguish it from the primary tissue formed by the primary meristem. The epidermis is often so filled \vith silica or flint, as to render the plants useful for scouring metal, and this accounts for the popular name. Certain subterranean branches of the rhizoma (a, Fig. 369) may have their funda- mental tissue gorged with reserve food, and thus form tubers which feed new growth in spring, and may sometimes serve as a means of vegetative reproduction. Among the vertical branches there is often a differentiation into the purely vegetative and the purely reproductive. The latter terminate THE SCOURING-RUSHES 543 4> rf^ Fig. 370. — Scouring-rush. ^4, male gametophyte or prothallus (i|fl) show- ing antheridia (a, a). B-E, spermatozoids of various ages, much more highly magnified. (Hofmeister, Schacht.) Fig. 371. — Scouring-rush. Female gametophyte or prothallus (*i^-) showing archegonia (a, a, a) and pseudo-roots {h). (Hofmeister.) in a cone-like aggregation of whorled sac-leaves. Each of these has a stalk ending in a shield-shaped expansion, six- sided from pressure. Behind each angle of the shield is a large sporangium dehiscing by a longitudinal slit (3, 4)- The spores are peculiar in having four slender arms which close tightly about the spore when moist, and spread apart in drjnng, thus serving to eject the spores. They are there- fore called elaters (5, 6, 7). The massive, much-lobed gametophyte bearing gametangia above, and the comparatively large sessile sporangia of the scouring- rushes, indicate a closer kinship with the adder-tongues than with the true ferns, and suggest that the Equisetina^ may have evolved from Hepatiese somewhat more moss-like perhaps than Anthoceros. They may be characterized as plants similar to fertis except in having 544 LIFE-HISTORIES relatively much greater stem-development, and in having the leaf- members n'horlcd, the sac-lcavcs in cones, and the spores with elaters. 194. The club-mosses (Class Lycopodinae) are well tj-pi- fied by Lycopodium (Fig. 166) which is popularly regarded as a kind of "moss" because of the general resemblance of the leaves and stems, in form and proportionate develop- ment, to the pseudo-leaves and pseudo-stems of many true mosses. Fig. 372. — Club-moss [Lycopodium sp., see Fig. 166.) A, gametophyte (^), showing archegonia (ar) and antheridia (an). B, old gametophyte (p) nursing a young sporophyte, Y- C', anthcridium ("ja) almost ready to discharge its spermatazoids. D, archcgonium, cut vertically to show the egg-cells (o), the upper canal-cells dissolved into mucilage (he), and tlae lower canal-cell (6c), -J". (Treub.) The gametophyte (Fig. 372) is bisexual and massive, as in the adder-tongues, and mostly saprophytic; and the cmbr3'o resembles that of a fern in having but a single cotyledon. Its development is essentially like that of the next type to be described. The stem often forks but sliows no secondary thickening. The leaves are unbranehed, and in some species are all much alike, while in other cases the sac-leaves are smaller than the foliage leaves, are crowded into cones, and serve chiefly as protective scales for the sporangia. Each sac-leaf bears but a single spore-case on its upper surface near the base. There are no elaters. THE CLUB-MOSSES 545 Fig. 373. — Mountain Selaginella (Selaginella helvetaci, Selaginella Family, Selaginellacecp). A, sporophyte, }. B, young sporophyte growing from macrospore. (Bischoff.) — -Native home, Eurasian mountains. Fig. 374. — Mountain Selaginella. Part of cone, showing a macrosporan- gium (a) containing three macrospores, and a microsporangium (6) discharging numerous microspores, ^^. (Schenck.) Another large group is Selaginella (Fig. 373) the sporo- phytes of which often resemble those of the club-mosses so closely that they were at first included in the same genus, and many forms in cultivation are still called by florists, lycopodiums. A most significant though inconspicuous difference is that Selaginella has two kinds of spores — minute ones, called microspores,^ which are very numerous in anther- like sacs termed microsporangia (6, Fig. 374); and macro- spores - (a) which are so large that four fill a macrosporangium. Both kinds of sporangia are borne singly on the stem just above or in the axils of upper leaves, in the same branch or cone. 1 Mi'cro-spore < Gr. mikros, small. 2 Mac'ro-spore < Gr. makros, large. 546 LIFE-HISTORIES Fig. 375. — Selaginellas. Germination of microspores. A-E, difTerent views of the spore showing the prothallus-cell (p), cells of the antheridium- wall (w), and the cell producing spermatozoids (s), ^^. In E the cell- walls have dissolved previous to discharging the spermatozoids. F, spermatozoids, ^f-"-. (Belajeff.) The spores begin to germinate while still within the sporangium. The contents of each microspore divides into several cells (Fig. 375, A-D) one of which (p) represents the vegetative part of a male gametophyte, the others constituting a male gametangium, in the center of which is formed a cluster of elongated gametes closely resembling the male gametes of a liverwort. After leaving the sporangium the microspores liberate their motile gametes by rup- ture of the wall. The large cell which constitutes the macrospore is rich in reserve food and begins to germinate by dividing into a number of small cells within the wall. Soon the macrospores are set free from the sporangium, and continue to germinate by forming a few archegonia on the upper side, which eventually i)rotrudes from the ruptured spore-wall shown in Fig. 376. After fertilization, the egg-cell divides into an upper and a lower half, the lower half grow- ing into an embryo, while the upper half develops into a peculiar organ called the suspensor (et). This by its elongation pushes the embryo, foot foremost, into the mass of vegetative cells upon which it feeds. The root and the shoot of the young embryo (Fig. 377) finally protrude from the macrospore, the foot (/) still remaining within as an organ of absorption in contact with the food supply. There are two cotyledons, which, containing chlorophyll, soon begin to make food for the plantlet, and aided by the developing leaves of the plumule, finally render the .young plant self-supporting. From the upper side of each cotjdedon (and often on later leaves) a flat THE CLUB-MOSSES 547 Fig. 376. — Martin's Selaginella (Selaginella Martensii, Selaginella Family, Selaginellacece). Germination of macrospore i^i), cut vertically, showing the female gametophyte protruding from the ruptured spore- wall (spm) and exposing an unfertilized archegonium (ar), but still enclosing two embryos {ernb^, emb-) which have been pushed down into the nutritive prothallus (/)/) by their suspensors {et, et). (Pfeffer.) — Native home, Mexico; much cultivated. Fig. 377. — Martin's Selaginella. Embryo (M"). cut vertically to show its suspensor (et), root (w), leaves {bl, bl), ligules (lig, lig), and tip of stem (st). (Pfeffer.) projection (lig) termed a Ugule,^ arises, which, by secreting mucilage, serves to l^eep the tender terminal organs from drying. The formation of macrospores that begin to germinate while still within the sporangium, marks a most important advance in the care of offspring ; for by this means not onh' are the chances of cross- fertilization increased, but the embryo is afforded more protection, and the young plantlet can be provided with a larger quantity of promptly available food while preparing for independent life. Just one step further is needed as we shall see, to attain the high develop- ment of parental care achieved by seed-plants. A similar differen- tiation of the spores and sporangia into male and female is found also in certain types of Filicinae, and in extinct Equisetinse. As with scoiiring-rushes and ferns, so with the club-moss class, the modern species but feebly represent their kin of the coal age. These include giant lycopods such as Lepido- dendron (Fig. 278, page 301) and Sigiilaria (Fig. 277, page 299) with much-branched trunks ten meters or more in height and often a meter in thickness, bearing cones as large as those of a pine tree, and forming extensive forests. 1 Lig'ule < L. Ugula, a little tongue. 548 LIFE-HISTORIES The Lj^copodinaD, which comprise in a very few genera about 600 species, occupy an intermediate place betiveen Filicina; and Equise- tinm in the relative size of their leaves and in their arrangement which may he either alternate or whorled; but, ichile having the sac-leaves or sacs often in terminal cones, the sporangia are always solitary and never on the under side of a leaf; and there are no elaters. 195. The pteridophyte division, fernworts (Pteridophyta) is made up of the three classes above named. Ferns being especially typical of them all, the plants of this division are conveniently designated as fernworts. While, as we have seen, mossworts were perhaps the first green plants out of water to succeed in standing upright, it is among fernworts that we first find vertical growth producing lofty trunks. Spores formed near the top of such a trunk are plainlj^ given an immense advantage since they may be dispersed over an extensive area. This highly beneficial provision for the welfare of offspring was made possible by the development of roots able to absorb subterranean moisture, and of leaves that could utilize it in con- nection with the air and sunlight. A protective function with reference to the sporangia or to tender parts of the stem was easily assumed by these lateral appendages, and in some cases became their chief or only office, as happened with the sheathing whorls of Equisetum or the cone-scales of Selaginella. Various differentia- tions of the stem-parts, gave rise to more or less branched ascending axes, either independent or climbing, or to more or less horizontal, often subterranean stems in which the capacity for storing food was often especially developed, and from which vertical branches or vertical leaves arose during seasons favorable for growth. For the bearing of spore-sacs either leaf-parts or stem-parts were available; and sometimes the one, sometimes the other was used. Nurse- plants were depended upon to foster the embryo and prepare it for independent, vigorous life; and the nurse itself was so well provided with reserve food that it could afford to dispense with food-making organs of its own to a considerable extent. It is thus perhaps of evolutionary significance that the gametophyte of fernworts is commonly much simpler in form and of less vegetative importance in the life-history of the plant than is the case in mossworts. An extreme of specialization in the reproductive function of the game- tophyte is found in those fernworts which have male and female si)ores, the latter having in general such a large amount of reserve food that the nurse-plant does not need to make anv for itself and scarcely protrudes beyond the spore, while the former having no embryo to nurse reduces its vegetative part to a single cell. Such gametophytes are virtually hysterophytic, and it is interesting to observe that types which do not produce macrospores but are THE PTERIDOPHYTE DIVISION 549 closely akin to those which do, have more or less hysterophytic nurse-plants. In endeavoring to trace the evolution of fernworts we con- tinually encounter the question as to whether a given type or organ of relatively simple form is best regarded as primi- tive or degenerate. The evidence available is often conflict- ing and has led different botanists to very diverse conclu- sions regarding the kinship and evolution of the different groups. Another stumbling block has been the difficulty of distinguishing between the resemblances that arise from similar adaptation to the same environment though in different lines of descent, and those resemblances which are due to inheritance even under cUfferent environments. It is now generally admitted, however, that the fernworts of the coal period attained much higher development than any which have survived, and that several important features, such as the development of macrospores, have evolved in- dependently in each of the three classes. We have thus good reason to suppose that the progressive evolution of the Pteridophyta was mainly accomplished in geological ages long past, that this progress took place along the three main lines represented by our modern ferns, scouring-rushes, and lycopods, and that these fernworts of to-day are the more or less degenerate descendants of giant plants like those preserved in coal. When we take the adder-tongue fern as possibly represent- ing the sort of plant which first evolved from a liverwort like Anthoceros, we must accordingly make allowance for considerable modification of detail due to special adaptations in the course of ages and to more or less degeneration. We cannot say much more than that our supposed ancestor of the ferns presumably had rows of large sporangia along the edges of the blade-like expansion of a growing axis which put forth, below, cylindrical projections for absorbing water. From such an ancestor, ferns, scouring-rushes, and club- mosses may perhaps be supposed to have evolved, one or another according as the stem-parts or leaf-parts reached greater or less, or about equal development, and the spore- sacs were multiplied or reduced in number and diminished 550 LIFE-HISTORIES or increased in size or otherwise modified to provide for the welfare of offspring. But however well these plants might succeed in utilizing under- ground moisture they could never take fullest advantage of the opportunities offered for life upon the land so long as they were dependent upon surface water to secure fertilization; and every fernwort still retains traces of its aquatic ancestry in the male gametes which must swim to accomplish their purpose. Thus fern- worts like mossworts are truly land-plants only during part of their life, although the former have attained a prodigious development upon land. Pteridophyta agree with Bryophyta in having archegonia, but are distinguished among cryptogams by developing true roots, stems, and leaves, in which a vascular system is developed. 196. Cryptogams and phenogams. The highest develop- ment of plant life is associated with the production of seeds, which afford the best possible provision for the welfare of offspring. There is abundant evidence to show that the earliest seed-plants differed but little from certain fernworts that had developed ma- crosporangia containing single macrospores. The first step toward converting such a macrosporangium into a seed might easily be taken if the macrospores remained attached to the plant until the archegonia were exposed, while the microspores, set free, were car- ried by wind to the attached gametophj'te there to germinate and effect fertilization. The final step would come, when, after fertiliza- tion of an egg-cell thus doubly protected by nurse-plant and spore- sac, the nurse-plant itself should be further protected bj' continued growth of the surrounding parts and should be fed by the parent while it was in turn feeding the embryo. An embryo thus fed through a connection maintained with the parent plant, and pro- tected by a sporangium wall which finally becomes detached from the parent for dispersal, is a seed; the macrosporangium with its inclosed macrospore and female gametophyte is an ovule: the micro- sporangia are anthers; and the microspores, pollen grains. When such highly differentiated spore-sacs are borne upon leaves we have sac-leaves which wc call either carpels or ■'itnmens. Pines and other gymnospermous plants (Figs. 258, 259, 260, 263) as we have seen, bear ament-like clusters of stamens or carpels each cluster forming what we may regard as a separate flower. A Selaginella which had certain cones producing microspores exclu- sively would thus be homologous with a staminate flower of Pinus, while an exclusively macrosporic cone would correspond to a pis- tillate flower. The morphology of the stamens and their parts in CRYPTOGAMS AND PHENOGAMS 551 nc — I Fig. 378.— Norway Spruce. Ovule cut vertically and enlarged to show the embryo-sac (c) filled by the prothalhis or endospertn and two archegonia (a), each with its neck (c) and swollen part (o) which contains an egg- cell with a nucleus {n); the nuctllus (nc) surrounded by the integuments (i) ; pollen-grains (p) from which come pollen-tubes (0 extending to the archegonia; and a part of the seed-wing (s). (Strasburger.) Pinus and related genera will doubtless be sufficiently clear without further explanation, but the carpels and ovules call for more de- tailed examination. Each carpel, as we have seen, bears two ovules on its upper side near the base (Fig. 258, 8). When cut in half vertically such an ovule exhibits the parts shown in Fig. 378. A single macrospore organically connected with the surrounding tissue constitutes what is termed the embryo-sac (e) . The rest of the ovule represents the macrosporangium, which is divided into a central part, the 7iucellus ^ (nc) in which the embryo-sac is embedded, and an outer layer, called the integument (0, which covers the nucellus except at the micropyle. Microspores, i. e., pollen grains, intrusted to the wind, are carried to the pistillate flowers. Caught by a 1 Nu-cel'lus < L. nucella, a little nut. 552 LIFE-HISTORIES - -ct ^ iW^^ 4 S n A Fig. 379. — Norway Spruce. Fertilization of egg-cell. A. ripe egg-cell with nucleus (on) and lower neck-cell (cl), -c- B, same, later, the tip of a pollen-tube (p) having entered the egg-cell and discharged into it the male nucleus (sw) which approaches the female nucleus (o«)- C, same, later, the two nuclei having become fused into one, which soon divides into four nuclei that move to the lower end of the egg-cell. D, lower end of the egg-cell showing two of the four nuclei which have moved into it. E, same after division of the four nuclei into eight. F, same after further division has produced four tiers of nuclei, all but the uppermost four being enclosed in cell-walls. G, same, after the middle tier of cells has elongated to form a suspensor which has pushed the lower tiers of cell into the prothallus (or endosperm) where they give ri.se, by repeated cell-division, to an embryo which is fed by the endo- sperm. The nutritious materials left over in the endosperm when the oxTile has become a seed constitutes the seed-food which supports the young plantlet during germination. (Strasburger.) spreading carpel, they come finally to the micropyle where the integument is often prolonged in such a way as to lead them directh'^ to the tip of the nucellus. Here they germinate Iw forming a few cells, some of which, remaining within the spore, represent the vege- tative part of the male gametoph}i:e; while others, the male gametes, form a hypha-like tulie which penetrates the soft tissue of the nucellus and feeds upon it like a fungus. Meanwhile the macrospore CRYPTOGAMS AND PHENOGAMS 553 Fig. 380. — Norway Spruce. Growth of embryo. A, early stage, if«. B, later stage, v. C, half-ripe embryo, showing below the protrusions from which the cotyledons are formed, 'i«. D, same, cut vertically. E, same, end view, showing the eight rudimentary cotyledons surround- ing the stem-tip. F, embryo, fully formed (?), cut vertically to show the seed-leaves or cotyledons (c), the seed-stem (h), the beginning of the root (pi), root-cap (cp), fibrovascular cylinder of root (cl), pith of stem (m), and rudimentary fibrovascular strands (op) surrounding it. (Strasburger.) 554 LIFE-HISTORIES (or embryo-sac) has been developing some very simple archegonia (a), consisting only of a large egg-cell (o), and one or more very small cells (c) representing the neck. See also Fig. 379, A. Present W the tip of a pollen-tube bearing the male nucleus reaches the egg- cell and discharges its nucleus into the female protoplast (Fig. 379 B). The male and the female nucleus fuse into one (C) and move to the opposite end of the egg-cell, there to form a group of small cells from which one or more embryos arise, but only one develops, in each seed. As in Selaginella, certain cells form a suspensor which pushes the developing embrj'o into the storage tissue of the game- tophyte. But in the pine and spruce this vegetative part of the nurse-plant, because of its long connection with the parent, is able to draw into itself a continued supjjl.v of nutritive material. Part of this nourishes the embryo till it develops root, stem, and leaves, while a surplus is stored around it as seed-food for the use of the plantlet when it has left the parent, and is ready to germinate (Figs. 379, 380). Not only is abundant food thus supplied to and for the embryo, but the sporangium wall (nucellus and integument) and the sac-leaf (cone-scale or carpel) are so well nourished after fertilization has taken place, that they grow enormously and be- come much hardened as organs of protection. The ripened ovule thus becomes a seed, and finally, as already described, separates from the parent and is aided in its aerial voyage to a home for life, by a wing derived from the carpel. The young sporoph}i:e has simply to grow after the mamier of its kind to become a tree and produce gametophytes which shall cooperate in the formation of highly favored offspring. In view of the many resemblances between Pinaceae and Lycopodiacese it has been thought that plants closely related to the club-moss trees of the coal-period may have been the ancestors of both of these cone bearing groups. It should be said, however, that the remains of extinct gymnosperms represented by Cordaites (Fig. 277, 5) contemporaneous with Lepidodendron, show resemblances to the ancient ferns which indicate that the ancestor of the conifers was more fern-like than might appear merely from a comparison of modern tj'pes. Cycas (Fig. 381) shows even closer affinity with ferns, as for in- stance, in the ample branched foliage-leaves which unroll as they develop, and the numerous sporangia borne upon a sac-leaf. In general the life-history is similar to that of Pinus, pollen spores being carried by the wind to a little chamber at the tip of a naked ovule to fertilize an egg-cell; but in this case the microspore upon germinating produces in the pollen-tube two motile gametes pro- CRYPTOGAMS AND PHENOGAMS 555 Fig. 381. — Japanese Cycad {t ycu6 rtvoluia, Cyead Family, Cycadacew) . 1, seed-bearing plant. 2, macrosporangial leaf or carpel showing the naked ovules (macrosporangia) near its base. 3, microsporangial leaf, or stamen, showing the numerous microsporangia (anthers) on its lower face. (Wossidlo.) — Tree growing about 3 m. tall; fruit densely hairy. Native home, Japan; commonly cultivated as "sago-palm." vided with numerous swimming-hairs. One of these fertilizes the egg-cell. After fertilization a seed is formed, an abundance of extra food being stored about the single embryo. The sporophyte as it develops becomes, as we have seen, singularly like a tree-fern and at the same time so closely resembles a Metroxylon as to be called by florists a "sago-palm." While we must of course regard this outward resemblance as more or less superficial, it gains significance from the presence of much deeper resemblances which have led botanists to regard the Cycad-type as a connecting link between the fern and the angiosperm. As already shown, the main difference between a gymnosperm and an angiosperm is that the latter_ incases its macrosporangia in carpellary leaves. Fertilization is accomplished, however, as before by means of a pollen-tube, which, starting from the stigma, has simply a longer road to travel before its tip reaches the egg-cell. Moisture to enable the microspore to germinate is afforded by a stigma, while food for the tubular cell is supplied by the tissues along its route. The parts concerned in angiospermic fertilization are shown in Fig. 382. When germinating, the pollen-cell produces two nuclei, one of which represents the vegetative part of the male 556 LIFE-HISTORIES Fig. 382. — Climbing Buckwheat (Polygonutii Convolvulus, Buckwheat Family, Polygonaceae). Pistil (V) during fertilization, cut vertically to show stalk-like base (/s) of ovary; stalk of ovule {fu)\ end of stalk {cha) ; the nucellus {nu), the micropyle, or opening to the nucellus {mi); the inner integument (n); the outer integument {ic); the embryo-sac (c) ; nucleus of the embryo-sac {ek) ; the egg-apparatus {ei) consisting of three cells, the lower one being the egg-cell and the two others com- panion cells which are thought to represent rudimentary archegonia; prothallial cells {an); style {g); stigma («.); pollen grains {p); and pollen-tubes {ps). A pollen grain falling upon the stigma produces a tube which grows down through the style, enters the micropyle, and penetrates to the egg-cell; here it discharges its (male) nucleus which fuses with the nucleus of the egg-cell and from this union an embryo arises. (Strasburger.) — The plant is an annual vine resembling buck- wheat but with greenish flo^vers; native to Europe but a common weed in America. Fig. 383.— Shepherd's Purse {Capsella Bursn-pastoris, Mustard Family, Criicifercp). Development of the embryo. A-D. successive stages, much magnified, showing the suspensor {ct), lower end of embryo {h), cotyle- dons (c), and the stem-tip (p) from which the plumule arises. (Han- stein.)— The plant is annual, about 50 cm. tall, with small white flowers and dry fruit; native of Europe; common as a weed in America. CRYPTOGAMS AND PHENOGAMS 557 gametophyte, while the other is the essential part of a gamete. Here then is a gametophyte reduced to the simplest terms. The female gametophyte formed within the embryo-sac consists of a few cells forming two groups which lie at opposite ends of the macrospore. Those at the micropylar end (ci) include an egg-cell which is thus advantageousl.y situated for fertilization by the pollen-tube entering the micropyle. The growth of the embryo from the fertilized egg- cell involves, as shown in Fig. 383, the formation of a suspensor (et) which pushes the developing germ well into the mass of food. In this example the embryo comes to fill the sporangium completely while still attached to the parent, thus forming an exalbuminous seed, in which radicle, cauliclc, and cotyledons are well developed. While it is not altogether clear how closed ovaries evolved from open carpels, the change may well have taken place as a result of the peculiar inrolling of the young leaf-lobes which primitive gymnosperms are supposed to have inherited from ferns. If ovules should form on such lobes while still inrolled, and the lobes should coalesce, the carpel would be angiospermic. However it happened, many highly important consequences of this advance are apparent. Most obvious is the greater protection of the offspring during the period of their dependence. There is also an enormous gain in possibilities for securing an advantageous cross. Thus a moist, projecting stigma becomes a target more likely to be hit by wind-carried pollen grains and more likely to insure their prompt germination, than the micropj^le of a naked ovule. Expansion or branching of the stigma, such as we find to be characteristic of wind-pollinated angiosperms, shows how well this new organ lends itself to increasing the chances of pollination and at the same time favors economy in the amount of pollen produced. See Figs. 2-15, 27, 36, 74 B, C, 109 C, D, 124 B, 153, 159, 165 //, 171 //, 243, 248, 254, 256 B, 257, 267 D, etc. A still further advance in these directions came when insects and other animals were attracted to the flowers, and their services thus secured as carriers of pollen. The attractive odors, bright colors, and alluring sweets, together with the marvelous arrangements of the various floral organs, present modifications of endless variety and offer one of the most fascinating fields in the whole range of botanical studv. See Figs. 22, 39 //, 48, 57, 59 77, SO, 91-100, 106, 133, 139, 145, 148, 156, 163, 164, 168 //, 172, 178, 187, 188, 189, 192, 217, 251, 275, 276, 282-293, 299, etc. This elaborate modification of stem-parts and leaf-parts cooperat- ing with pollen-sacs and ovules to form what we call a flower brings with it the further possibility of utihzing these accessory organs, 558 LIFE-HISTORIES +i c3 c ■ M « oj 5 «^ +j S Si OJ ^ cj t< -fi O o o ^ "^ , s o o o g S Shh ?= in o o (H S 5 •- cS rt O O H ^ 73 ™ Q d S M fl ? § 3 C > -2 >-' Si M CX! aj_o o o (U O M C 1 O r-" +J O fH-^-r^.^i SS-^.C fi c3 ^X & S O >>'3-ti ^ 5; ■^^-^-■s'i.oSS;5 °;a |:a °^g>>«S-2gc3|g-§g M s ti cQ-a"2 "5 ■*^ ^ ov^fc,- 3 oO S^ ^-^'" « a; MS c S m i^ >.-^ ■^:^ a-n a^ ^ £ ^ i: o.S ^'" hfiS 0^0 ^^x !h J r w""^ "^ . c ".S ?.S O S g-S-= Sax) >>g S a bo d o - >'^ — > !h ??T. O— . > G G^ " r3 g G ^ 5:; S t:' bO o > E^ X^^-O iiT3 »-3^ 00 C 3 m rj ^ £ _ m — ,0 S O S O £3 2 s _ £-2 O g G tH tH £. O t< o !U 559 560 LIFE-HISTORIES or certain parts of them, to further protect the eml)ryo and pro- vide for its surer and wider dispersal. Hence arise protective shells (Figs. 23-36) and various aids to dissemination, including wing-like or plume-like appendages (Figs. 55, 59, 76, 159, 197, 215, 248, etc.), for catching the wind; elastic springs for propelling the seeds to a distance (Figs. 164, 165), and succulent parts (Figs. 88-110) which being attractive food, lead animals to swallow indigestible seeds and transport them often to enormous distances. Thus, it is in plants which form seeds within a case that we find the most perfect provision for the welfare of offspring; and it is doubtless because of this provision that angiosperms are the dominating plants of to-day. In concluding our survey of vegetable evolution it may help us to a just perspective if we briefly review the main steps which the ancestors of angiosperms appear to have taken in their long upward journey. The accompanying diagrams (Fig. 384) will serve to recall the chief facts and conclusions already presented regarding the phjdogeny of these highest plants, and also the ontogeny of modern types representing the supposed links in the series. In accordance with the "law of recapitulation "(see page 435) we find that the younger the stages the more they are alike, and that imma- ture stages of the higher types correspond to mature stages of lower types, the youngest stage of each being a single cell like the supposed ancestor of all. This reproduces simply by fission, a process which is retained by all higher forms as growth by cell-division resulting in cell-rows, cell-plates, or cell-masses variously differentiated into tissues and ultimately, tissue-systems. Vegetative reproduction occurs also in these higher forms through the occasional separation of cells or cell-groups cai)able of independent life. Sexual reproduc- tion appears with the fusion of two protoplasts to form one which afterward increases by division. In the aquatic forms the fusing protoplasts soon became motile and this motility is long retained in the male by their descendants while adapting themselves to a terrestrial life, and disappears finally when this is fully attained. The single protoplast resulting from tlie fusion of two gives a second unicellular beginning and thus the life-history of an individual becomes divided into a sexual and a non-sexual stage or generation. When the female ]:»rotoplast remains attached to a plant in the sexual stage until after fertilization there results an egg-cell wliich becomes a non-sexual embryo if the connection be maintained so that the sexual generation may nurse the non-sexual. This new begiiming, nursed by the more primitive stage, affords, it would seem, a good opportunity for the transition from life in water to life on land. Then, too, the nursing, when not excessive, both permits and encourages the highest development of the non-sexual genera- tion. Finally, it nurses the nurse, and thus through ample provision for both nurse and nursling produces a seed well cared for in every way. This is the greatest achievement of the vegetable kingdom. CHAPTER XIII THE PLANT'S PLACE IN NATURE 197. The three kingdoms. It has long been the general opinion that all natural objects fall readily into three main groups or kingdoms — the mineral, the vegetable, and the animal. Over a century ago the characteristics of each kingdom as understood at the time, were given by Linnaeus in his famous aphorism: ''Minerals grow; plants grow and live; animals grow, live, and feel."' This threefold division is still recognized as convenient, and the distinctions given are admitted as valid to a considerable extent; but that a mineral grows in essentially the same way as a plant, and that a plant lacks any quality that is found in all animals, would not generally be admitted b}^ the naturalists of to-day. In order to understand modern views regarding the plant's place in Nature we need to consider what is meant by grow- ing, living, and feeling. By "growth" Linnaeus seems to have meant merely increase in size. Yet is not the enlargement of a seaweed or a fish essentially different from the so-called growth of a salt crystal in concentrated brine? The crj'stal gets larger simply by additions upon the outside, while the living body increases in size by the incorporation within itself of substances de- rived from without. IMoreover, the crystal as it enlarges remains substantially the same throughout, and all the parts behave alike. In a growing body on the contrary there is a progressive differentiation of parts and functions. Hence we cannot say that a mineral grows in the same sense that an organism grows. But does not Linnaeus express the differences above in- ^ Lapides crescnnt; vegetahilia crescunt et I'ivunt; animalia crescunt, vivunl el sentiuiil. 561 562 THE PLANT'S PLACE IN NATURE sisted upon b}^ saying that organisms are alive? Doubtless he meant to do so; yet what did he mean by life without any trace of feeling? What sort of feeling can a sponge or a jelly- fish have that we must deny to a climbing-plant, or to a swimming-plant that moves toward the light? Our only evidence that the animal feels is that it responds })y move- ments to certain stimuli. When we watch plants carefully we find that they also respond to similar stimuli. Thus we are left without any distinction between plants and animals; and since what "feeling" stands for in animals is found in plants as well, it would seem that this same "feeling" might be what best distinguishes living from lifeless bodies, and so underlies the various manifestations of life. According to a view which we must examine more at length it is because of their purposeful activities that animals and plants are called living, and because of their coordinated parts, organic. All other bodies are then appropriately termed lifeless or inorganic. This modern view of Nature implies a revised classification which may be conveniently presented in the following tal)uiar form. f Inorganic Realm or Mineral Kingdom. j ^ • T^ , [ Vegetable Kingdom. Organic Realm i . . , ^,. , ^ [ Animal Kingdom. 198. The inorganic realm, it must be admitted, presents many points of fundamental similarity with the organic. Thus volume, mass, resistance, form, and all such physical properties are common to both realms. Furthermore, all the chemical elements found in animals or plants occur also in minerals, and often in the same combinations. Indeed many of the so-called "organic compounds" once supposed to be formed only within living bodies are now made in chemical laboratories by purely artificial means. Oil of wintergreen, indigo, and madder-red are examples we have already had occasion to notice. Many others might be added, including certain sugars. It has been urged that some day it may be possible to manufacture protoplasm artificially, and so break down the distinction now made THE INORGANIC REALM 563 between living and lifeless things. Certain naturalists go so far as to insist that even to-da.v no fundamental difference can be found that will absolute!}' distinguish all organisms from all minerals. They say that life consists merely of the activities of protoplasm, that these are determined solely by the combined properties of tlie several chemical elements of which protoplasm is composed, and that already it is possible to match every one of the fundamental properties of protoplasm by an artificial process. For example, if a crystal of copper sulphate be thrown into a solution of potassium ferrocyanide there is formed at once, by precipitation around the crystal, a membrane resembling a cell-wall, which presents every appearance of growing as a consequence of pressure from within and fresh precipitation wherever the two solutions come in contact. The artificial cell thus produced may attain considerable size and branch in various ways. Another striking experiment consists in putting a few grams of mercury into a flat-bottomed dish containing a 10% solution of nitric acid in water, and then placing a crystal of bichromate of potash on the bottom about an inch away from the mercur}'. As the potash salt dissolves it becomes surrounded by a reddish cloud which finally reaches the mercury. Then suddenly the mercury becomes agitated, moves toward the crystal, and envelopes it, very much as certain of the lower animals seize and swallow their pre}\ Finally, an experiment held to be of profound significance as showing in a mineral substance the very essence of growth and reproduction attended by anabolic and catabolic reac- tions, consists in adding to a certian quantity of acetic acid, chemic- ally equivalent amounts, successively, of phosphorous pentachlo- ride, zinc ethyl, and oxygen. As a result there is formed double the original amount of acetic acid plus several substances which cor- respond to the by-products of organic metabolism.^ Here, then, we have what is regarded as the life-history of a molecule, which, so long as it is fed, grows and reproduces as if by fission and excretes much as a bacterium would do. ^ For the benefit of students familiar with organic chemistry the transformations above referred to may be expressed by the following equations copied from Les Problcmes de la Vie, by E. Giglio-Tos. Part I, 1900, pp. 20, 21. Acetic acid (2 molecules) Phosphorus pentachloride Acetyl chloride Phosphorus oxychloride Hydrochloric acid CH3 COOH + PCI 5 = CH, 1 COCl + PCI3O + HCl COOH CH3 + PCI, = COCl 1 CH3 + PCL,0 + HCl 5G4 THE PLANT'S PLACE IN NATUKE What is the utmost that may be inferred from such experiments? Have lifeless things really been made to act as if they were alive? It is plain that all we have here are simply imitations of isolated vital processes, and not such a coordination of activities as character- izes a living being. Living protoplasm does not merely feed, or grow, or reproduce, or respond to stinuili: it does all these things at once, and more; and its activities are so coordinated as to accomplish definite ends. Nothing which can do all that protoplasm does has ever been manufactured. Supi)osing it were possible, however, to effect a combination of elements which would imitate all the physical and chemical activities of protoplasm, and all at once; what would that mean? AVe could be sure that such artificial protoplasts would always do the same thing under the same condi- tions, and that corresponding parts would always act exactly alike. Acetyl chloride Zinc ethyl Methylethylketone Zinc chloride CH3 1 1 CH. 1 cn. CH3 1 1 CO 1 COCl + Zn COCl 1 CH; "cHs 1 = 1 CHs CHs 1 + Zn CHs CHs 1 CO 1 CH CHs Methylethylk( 'tone Oxygen Acetic acid CH, CHs 1 CHo CO + .30 = COOH CHs 1 CH:5 COOH CHs CHs CH2 bo 1 + 30 = COOH CHs 1 CHs " COOH Thus for every two molecules of acetic acid/o(/?' are finally produced. THE INORGANIC REALM 565 But this is precisely what seems not to happen with living proto- plasts. No two living things are ever expected to act in the same way in all respects. Furthermore, the theory of evolution as we have seen, assumes that the halves of a cell divided by fission have individual differences such as we should have no reason to expect in the artificial protoplasts of a single batch. We may well believe that something quite essential to life will always elude the efforts of any man to create a living thing. Nothing that has been done gives any assurance of the possibility of realizing such a dream. It used to be supposed that the transformation of a lifeless into a living thing might be scientifically demonstrated to occur in the appearance of bacteria in a putrescible substance. The supposed transformation was called spontaneous generation, a term also ap- plied to an older notion widely held that manj^ of the lower forms of life arose spontaneouslj- from dead matter, as maggots in cheese or pond-scum on a stagnant pool. What gave rise to the belief that bacteria were spontaneouslj^ generated was that sometmies after a broth had been boiled in a flask and all air excluded, bacteria did appear within a few days. Investigation showed, however, that in these cases spores were present which were able to resist an amount of heat fatal to the plants in their actively dividing condition; and one had only to repeat the boiling till all the plants were killed in order to obtain a broth which could be kept indef- initely. Science was thus left without any proof of spontaneous generation, and it must now be said that so far as we know every organism has had a living parent or parents. The aphorism "All life comes from former life " still remains undisproved. Those who doubt that there is any essential difference be- tween living and lifeless things may still urge in favor of their view that certain plants are to all appearance practically lifeless during their so-called resting period; and if that be true we have a lifeless thing coming to life simply as a con- sequence of a change in temperature. So also, many simple organisms when frozen lose all trace of life except that they live as before, w^ien they are thawed out. They may be submitted to a temperature of 250° below zero centigrade for any length of time and will resume their activities when warm. Or, they may be dried so as to show no more sign of life than so much inorganic dust, and then be revived by moisture. Thus when there is too much or too little heat, or not enough water present to permit signs of life, an or- ganism may be as inactive as a crystal and indistinguishable from a lifeless thing except in so far as under favorable condi- 566 THE PLANT'S PLACE IN NATURE tions it again becomes active. We should remember, how- ever, that even granting in such cases the appearance of hfe in a body which before was Hfeless, it was a reappearance; and this previous hfe again confronts us with the original problem. We still must ask, Is there not some profound difference between a body in which life reappears and one in which hfe never has appeared? To this question the doubter may reply: "Let us go back then to the first of living things. Evolutionists suppose this to have come from something that had never been alive before. Does not the change here assumed imply that the inorganic realm merges so gradually into the organic that some organisms differ no more from some minerals than one organism or one mineral does from another?" Not at all. It does not follow just because one thing is transformed into another that the new may not be profoundly different from the old. An evolutionist, therefore, is free to believe that when the first living creature appeared upon the earth, a form of existence essentially different from any that had been here before, came into the world. We may suppose that as the earth was cooling from its molten state there were formed according to chemical and physical laws acting under conditions not since repeated, aggregations of com- pounds like those now found only in the organic realm; and that as soon as the temperature became favorable these aggregations liccame alive, exhibiting the activities of a living thing much as a revived creature would do. In saying this, however, we have admitted only that life may have appeared as soon as the conditions required for its manifes- tation were present. We have not implied that life is a product of the chemical and physical properties of matter,- however necessary certain material conditions are to the manifestation of life in an organism. It may be freely ad- mitted that chemically and physically considered certain lifeless bodies are indistinguisliable from certain living ones; that indeed one and the same body may pass from one condi- tion to the otlier without change of properties, and that when alive all the activities of its parts are describable in chemical and physical terms. All this would necessarily THE INORGANIC REALM 567 be true if the life principle were an immaterial something M'hich could find expression in an organism only through material bodies presenting favorable properties under favor- able conditions; and if life be not inherent in matter we should expect that all attempts to find any difference between the matter with which life is associated and that which is lifeless, would fail, as they have done. It may be urged against the supposition of life having entered into lifeless conipoimds as a controlling force in the beginning that this virtually concedes the possibility of lifeless bodies becoming alive, and merely substitutes a wholl.y mysterious idea for a chemical con- ception of the process. It is conceded that an evolutionist who as- sumes a fii"st living thing to ha\'e been produced m some way can hardly escape supposing this living thing to have become alive; but neither does he escape facing a mystery whether he tries to think about it in chemical terms or not. Scientific thinkers try to avoid unnecessary assumptions. Why then should we assume that there ever was a first living thing? There can be no more need of so doing than of trying to imagine a time when the uni-\-erse began to exist. Parts of the miiA'erse ma}^ always have been alive. Yet granting this possibility, it may be argued that since no life could have existed iil)on the earth when it was a molten sphere we ha^'e still to account for the presence of life upon it to-day. The answer of modern as- tronomers to the question as to how our earth came to be mhabited is afforded by the theory of panspermia.^ This theory supposes that innumerable living spores are traveling through the celestial spaces impelled bj- the radiation pressure of light. It has been found by experiment that minute particles allowed to fall in a vacuum are driven from their downward course by a beam of light; and it has been calculated that spherical spores 0.00016 mm. ui diameter — such as we have good reason for believing to exist although too small to be seen through ordinary microscopes — would be moved readily by the pressure of sunlight if they should once pass out of our atmos- phere. Air currents would carry such bodies to a height of about 60 miles where, if electrified by a radiating auroral discharge they would be carried beyond our atmosi)here and bej'ond the effective pull of gravity. The light pressure could then propel them to the orbit of ]\Iars in about twenty days, and beyond our solar system in little more than a year. Thousands of years might be required for them to reach other solar systems; but meanwhile the extreme cold, dryness, and other conditions prevailing in space would be favorable to their remaining alive and resting indefinitely. Within a solar sj'stem particles of dust are being attracted towards the sun. If a traveling spore should meet one of these dust particles it might be 1 Pan-sper' mi-a < Gr. pan, universal; spenna, seed or living germ. 568 THE PLANT'S PLACE IN NATURE carried into the atmosphere of a planet, and without harm come to rest upon its surface there to germinate if the concHtions proved to be favorable. It would thus api)ear that we have abundant scientific warrant for supposing that the first living things upon our tiarth were resting spores which came through vast spaces from sonu; other planet; and that our simplest forms of life are being distrilnited sim- ilarly throughout the universe, just as similar living germs have been carried from planet to planet during endless ages for which it would be idle to seek a beginning. Life having always existed does not need to be accounted for in terms of physics and chemistry.^ If not in physical or chemical terms, how then can we define that which distinguishes all living from all lifeless things? Some naturalists have seemed to think that this question could best be answered by trying to interpret the more complex manifestations of life in the higher organisms through a study of the simpler manifestations of the lower forms: but this means trying to explain the life of which we know most by that of which we know least. A method just the reverse is surely more promising. When I ask myself what it is that makes me alive, my answer is: Not any par- ticular arrangement or movement of material particles of a certain sort, but rather an immaterial something which to some extent can control the arrangements and movements of such particles in accordance with purposes peculiarly my own. My body is alive only so long as it affords opportunity for the exercise of my ivilL It is my power of choice that makes me alive. What I choose gives me my character. My life and my individuality come from my power to choose and the way I use it. If you should ask me how I suppose an immaterial existence can exert an influence upon what is material, I must ansAver that I have no more idea than I have how mind can affect mind or matter affect matter. The real nature of (Mtlier is doubtless very imperfectly expressed by any scientific defini- tions of them that were ever offered; but I do not need to know the ultimate truth about them in order to feel justified in be- lieving that somehow in ever}^ living creature the free will of something mental gets expressed through something material, ' For a fuller account of the theory of panspermia the student may profitably consult Worlds in the Mukiiuj by Svante Arrhenius, 1908, from which the calculations given above have been taken. THE ORGANIC REALM 569 whatever mind or matter may be and however they may inter- act. If I am right in my behef , then it follows that this power of choice which we have already seen reason to regard as the fundamental factor in organic evolution, is indeed the very essence of life. On this view an organism is recognized as alive when it shows signs of control from within, manifested by activities regarded as purposeful, and in so far peculiar to itself as to defy exact foretelling. It has been well said that no arguments can ever force a person to believe that even he himself has a free will; for, if it were true that he had a free will he must always be free to choose the other alternative. The reader will understand, therefore, in what follows that as a believer in free will I wish merely to show some of the consequences of this belief to anyone who is dis- posed to share it with me. Those who agree with me will feel free to believe in the workings of will throughout the universe. They will conceive of the difference between a lifeless and a living thing as simply this: the lifeless thing must do whatever it does, while the living thing may do this or that. From this it follows that to us and to all other living things belongs in various measure a power of preference.' The range of this power in us though limited by a Power beyond ourselves increases according as it is used. And shall we not say that the Power which limits while it permits the exercise of our separate wills is reflected in what we call the inorganic realm? 199. The organic realm. A typical living organism may be conceived of as a self-building boat formed of materials taken from the inorganic stream in which it floats, but con- trolled by an indwelling, immaterial power capable of steer- ' If the reader has studied philosophy he is doubtless aware that certain thinkers who concede a power of choice to all living things refuse to limit this power to the organic realm, but hold that a certain measure of conscious freedom is permitted to every particle of matter. They favor this view as enabling them to unify their conception of the universe, and at the same time to recognize the immanence of God throughout. The unification which is gained, however, by saying that all things are alive, deprives Life of any special meaning. For if nothing is really lifeless, being alive means no more than simply existing. What- ever truth there may be in saying that all Nature is somehow alive seems to me to be implied in the view outlined above. 570 THE PLANT'S PLACE IN NATURE ing as it chooses. The materials of such a Hving boat as we have imagined would be continually dissolving into the stream; while, at the same time, fresh inorganic material, admitted by the indwelling power, would be building the structure anew. So long as these materials formed part of the boat or showed signs of having once belonged to its organized structure, we should call them organic; and we should apply the same term to any compounds possessing the same properties. So long as the materials were arranged in a way to permit the indwelling chooser to act through them directly, they would constitute living substance. Until thus controlled they would be simply lifeless substances; after they had passed from this control they would be dead. Be- fore they had been organized and after they had ceased to bear the marks of organization we should call them inorganic. The materials of which these wonderful boats are made consist chiefly, as we have seen, of the elements carbon, hydrogen, oxygen, and nitrogen. It is perhaps significant that each of the four is preeminent for certain properties which are in marked contrast with what characterizes one or more of the others. Carbon, in a sense, is the most solid of all known substances. It requires the highest tempera- ture to melt it, and in its diamond condition exceeds all other materials in hardness. It is remarkable for the dif- ferent ways it can combine, and as entering into more com- pounds than all the other elements taken together. Hydro- gen, on the other hand, is of all common elements the most fluid. It requires the utmost cold to freeze it and remains gaseous under the highest pressure. It is remarkable for the ease with which it may be made to pass from one com- pound to another. Oxygen, also a gas at ordinary tempera- tures, is preeminent for the stability of its compounds, and for the activity it shows in combining; while nitrogen, simi- larly gaseous, is in marked contrast as being most difficult to combine and most unstable in combination. We have here, then, three of the most fluid of substances, gaseous at all life-temperatures, combined with the most solid sub- stance known; and among the four we find the readiest com- biner, and the most inert; the easiest to displace, and the THE ORGANIC REALM 571 most firmly grappling; the stablest, and the most unstable, of all common elements. From the interplay of such oppo- sites extraordinary resultants should appear. If localized wills are to gain progressive expression through masses of matter we should expect that the materials used would have both mobility and fixity. That is to say, we should look for a constant flow of particles, and at the same time relative permanence in the arrangements into which they temporarily enter; for only thus could change be added to change. Furthermore, if such a will were to be free to oppose outside influences as well as to yield to them promptly, the material through which it responded should have unusual stability associated with an instability resembling that of explosive compounds. Accordingly, since the properties of a compound result from the properties of its constituent elements more or less modified by mutual influence, it may not be altogether fanciful to suppose that the solidity of carbon, the fluidity of hydrogen, the stability of oxygen, and the instability of nitrogen may be especially significant as properties which in combination largely account for the almost paradoxical properties of living substance which is characterized by permanence with constant change, and sen- sitiveness with resistance; and having withal such an exceed- ing delicacy of balance that an infinitesimal force is suffi- cient to release energy in one direction rather than another. Of course a complete explanation of the chemico-physical properties of this living substance, if ever attainable, mast be vastly more complex than might appear from the vague suggestions given above as to possible connections between a few important facts. The purpose of these hints is merely to indicate how increasing knowledge of matter may help us to understand the conditions under which life is possible, and so be of profit in our dealings with the world in which we live. It seems only reasonable to assume that the prop- erties inherent in the materials of which all living bodies are composed should make possible and largely determine the activities they all exhibit. Whatever may be the explanation of the fundamental properties of protoplasm, they are indeed, marvelous to 572 THE PLANT'S PLACE IX NATURE contemplate. Our simile of the living boats would need to ])e much elaborated l)efore it could well portray the bewilder- ing complexities of action and interaction which go on within the simplest organisms. We said that the materials of each organic craft were being continually lost and continually replaced. But we must remember that often more is added than is lost; then the organism grows. It should be said also that so long as inner impulses control the arrangement of the fresh material, and thus partly determine the character of the growing structure, the arrangements formed usually show progressive fixity, each arrangement determining some- what the arrangements which follow and rendering them less susceptible of change. Hence, old age with its decreasing mobility and final death is an incidental result of the pro- gressive fixity which makes structure and habit possible. Yet under certain conditions, as we have seen, protoplasm passes into a fixed condition, to all appearance like that of death, but from which it may revive with j'^outh renewed. A similar renewal of mobility distinguishes reproduction from mere growth, and offsets death in the economy of na- ture. Our living boats, then, grow old, and may die; or, they may become inactive and afterward resume activity with youthful vigor. When they have grown large enough they form out of themselves new boats, similarly invigorated and similarly relieved from the hamperings of old habits or fixed arrangements; — but not entirely, for each is built upon much the same lines as its parent, and in its own building can only modify the design. Yet what wonders may result from an ever so slight power of modification bearing the slightest im- press of a choice ! This part may be modified in one way, that in another: and morphological differentiation with phj'sio- logical division of labor may ensue. What one brief life can- not accomplish, another may; individuality, heredity, adap- tation, organic evolution — all are here implied. Such are the powers and potentialities of a mass of living jell}'. Our imagined boats each built and captained by a choos- ing power are meant to represent living things in general. All plants and all animals, as we have seen, differ from all minerals in having differentiated organs adapted to the needs THE ORGANIC REALM 573 imposed by the conditions under which they hve; and in detaching certain portions of their substance, such as seeds or eggs, capable of developing from infancy to old age by taking in as food suitable materials, transforming them, then building them into their bodies, and finally after utilization, eliminating them as waste products. Such being the charac- teristics of all living things we should hardly expect any well- marked peculiarities by which all animals can be distin- guished from all plants. In fact there is not a single point of difference available for separating sharply the animal from the vegetable kingdom. The Linnsean criterion of feeling we have already found to fail when applied to primitive types. So also the popular criterion of motion or locomotion must be rejected by anyone acquainted with the lower forms of life, which include not only motile plants but fixed animals; and we have only to remember the absence of chlorophyll from many plants to realize that even this highly charac- teristic vegetable substance does not afford an adequate mark of distinction between the two kingdoms. Not a few organisms behave like plants at one stage, and like animals at another. A considerable number of these vegeto-animal organisms have been claimed alike by botanists and zool- ogists. The uncertainty in classifying such forms has led to the suggestion that a third organic kingdom, intermediate between the animal and the vegetable, be recognized to include all the kinds in dispute. This suggestion has not met with much favor among naturalists, for instead of lessen- ing the practical difficulties of the case it would really double them by giving us two uncertain boundary lines instead of one. Our best way surely is to meet the difficulty by trying to define as strictly as possible what may be conveniently meant by animal and plant, remembering that whatever definition we frame is sure to be arbitrary. We know that the great majority of plants organize in- organic material, while the great majority of animals, if not all, have no such power and so must depend upon plants for their food. The raw materials which plants build up into food have only to be absorbed in solution from the water, soil, or air in which they live. The elaborated food of animals, 574 THE PLANT'S PLACE IN NATURE on the other liand, is generally sohd and so requires to be dis- solved in a digestive cavity within the body before absorp- tion is possible. Plants which can make their own food from materials always at hand have no such need for traveling about in search of food as most animals have; and while food-seeking calls for the special sensitiveness which Linnseus termed feeling, food-making involves only such manifesta- tions of irritability as might easily escape his notice. A typical plant is thus a sedentary food-maker, a typical animal being a roving eater. It is only when plants lose more or less their power of making food, and animals their power of locomotion that doubt arises as to their kingdom, and then the question has to be decided not so much by rules and definitions, as by evidences of their kinship to un- doubted examples of vegetable or animal life. A Bacterium, for example, is classed as a plant because of re- semblances to a Nostoc which outweigh its animal-like motility and dependence ujpon organic food. If a Bacterium should develop a digestive cavity for the reception of its food we should say it had become an animal. The most fundamental difference between plants and animals appears thus to lie in the ways they prefer to get their food — the vegetable way being to make the best of what comes to it, the animal choosing rather to capture what plants have made. Returning to our simile of the boats it might be said that the vegetable craft choose to anchor in a stream of materials which they organize into food, while the animal craft navigate the stream and repair their losses entirely from other vessels. A modern revision of the aph- orism of Linnseus, still, however, confessedly inaccurate, might read: — minerals crystalhze; plants organize or re- organize materials which they absorb; animals reorganize food which they have swallowed. 200. Plants in general. The foregoing reflections upon the way natural objects are related to one another are in- tended especially to emphasize the pivotal place which plants hold in the economy of nature. It is now believed that the wide and rich possibilities of earthly life could not have Ix^en gained or maintained \\dthout plants. Plants were PLANTS IN GENERAL 575 presumably the first things to manifest individuahzed powers of choice upon our planet; and plants have so chosen that animals have been l)orn and enabled to realize the highest opportunities of life. Hence, because some plants have chosen as they did, we are now able to choose as we do. One of the earliest results of plant choice was doubtless the fixed mode of life; and with this \vt may connect the building of a protective cellulose covering and framework readily permeable by fluid raw-food materials. The firmness of this framework, combined with its power of conducting fluids, permitted eventually the building, even upon land, of enormous structures hundreds of feet in height. Fixity, together with their powers of absorption, have thus enabled plants to attain in some cases the longest life and the greatest size of any organisms. Preferring to be home-keepers rather than hunters their more tranquil lives have given neither opportunity nor occasion for such specializations of sensitive- ness as are involved in the rapid and highly complex re- sponses of animals. Hence it is that their modes of life appear so different from ours although but modified mani- festations of the same fundamental, vital power. It is just because of the contrasts between vegetable and human life that plants are able to serve our needs in so many ways. They feed us because they have retained the power of food-making which our line of life has lost. They shelter us because they have learned how to form in wood a con- structive material better than any we or our ancestors could ever make. They clothe us because the cellulose fibers of their bodies make a better covering than the hairs our bodies have retained. They warm us and work for us because they can store up sunshine, as we cannot. They help to make us well partly because their waste-products are so different from ours. They excite our admiration by doing to perfec- tion so many things we cannot do at all. They harm us only when we have not learned to know them and to behave toward them as we should. There are thus abundant reasons why mankind should study the economic properties of plants as fully as possible. We may be sure there will always be much to learn regarding the relations of plants to human 576 THE PLANT'S PLACE IN NATURE Avelfare, and that all we shall learn about this or any other aspect of their lives may serve to enrich our own. Thus, an inexhaustible interest as well as an increasing command over the resources of our world is the reward of our endeavor. An even deeper interest than belongs to any idea of use or harm is also sure to be aroused by watching the behavior of these our fellow-creatures that are so different from us in almost every way. For, again, these very differences give them an endless fascination as objects of study; and, finall}', it is just these differences which enable us to distinguish the incidental from the essential powers of life. In these or- ganisms we see individualized wills expressed under condi- tions as different as possible from those which permit the action of our own power of choice. We cannot hope to fathom the mysteries to which the humblest plant may lead us; we can only say with the poet Tennyson — "Flower in the crannied wall, I pluck you out of the crannies. Hold you here, root and all, in my hand, Little flower — but // I could understand What you are, root and all, and all in all, I should know what God and man is," INDEX All numbers refer to pages, heavy type indicating illustrations. Abnormalities, 436 Absinthe, 159 Absorbent cotton, 228 Acacia Senegal, Gum Arabic Tree Accommodation versus competi- tion, 454 Acer Saccharum, Sugar-maple AceracecE, Maple Family Acetic Acid, 15G Achene, 351, 386 Aconite, 182, 189, 190 Aconitine, 190 Aconituin Napellus, Monkshood Acorn, morphology, 375 Acorus Calamus, Sweet-flag Acquired adaptations, 441, 443; characters, 443, 445 Acquirement, permitted by nat- ural selection, 450; versus selec- tion, 452 Acrid juice, 357 Actcea spicata, Baneberry Adaptation, 428, 572 Adaptations, 431; acquired, 441, 443; characteristic, 442; in- dividual, 442; origin of, 442; selected, 446; sudden, 457, 459 Adder-tongue, 532, 533, 558 Adder-tongue Family: adder- tongue, 532, 533, 558; grape- fern, 532, 533. Adhere, 365 Adhesion of organs, 365 Aeration, 530 ^Estivation, 349; convolute, 369; imbricate, 349, 354; open, 371; plicate, 381; pUcate-convolute, 381; valvate, 349, 354 Agaricacerp, Gill-mushroom Fam- ily Agurir.us campeslris, Field Mush- room Agriculture, primitive centers, 122, 123 Air-cushions, 284 Air-plant, 508 Albumen, 316, 351, 352 Albuminous seeds, 355 Alcohol, 156 Alcoholic beverages, 156 Alcoholic fermentation, 495 Alga Subdivision, 395, 396 Algce, Seaweed Subdivision Algai, as gonidia, 509; in general, 491; of hot springs, 475 Algo-fungul air-plants, 509 Alkaloids, 150, 177, 181 Allium Cepa, Onion Allspice, 128, 130, 177; oil, 130, 297 Almond, 35, 42, 120, 124, 167, 363; kernel, 114; oil, 296; philopena, 365 Alpine Rose, 378 Alternate, floral organs, 350, 354; leaves, 342, 352 Alternation, of floral organs, 350; of generations, 485, 512 Althcea officinalis, Marshmallow Amadou, 239, 241 Amanita musairia, Fly-amanita phallnides. Death-cup Amarantacece, Amaranth Familj- Amaranth Family, 378 A maryllidacece, Amaryllis Family Amaryllis Family, 397 Amber, 288 Amentaceous inflorescence, 373 Aments, 373 American, aspen, 264; food-plants, 124; elm, 259; laurels, 416, 417; sycamore, 267, 268; wood- anemony, 205 Ammonia, 33 577 578 INDEX All numbers refer to pages, heavy type indicating illustrations. Anabolism, 84 Anabolisni imitated, 563 Anacardiacece, Sumac Family Analogous organs, 321, 32(j Analogues, 321, 322, 326 Analog}^, 326 Ananas salivas, Pineapple Anatropous ovules, 346, 355 Ancestral forms vague, 441 Ancient food-plants, 124 Andrcecium (see also stamens), 346, 347 Andropogon halepensis, Johnson Grass Sorghum, Broom-corn Anemone quinquefolia, American Wood-anemony nemerosa, Wood-anemony Fulsalilla. Pasque-flower Anemony, 328-356, 341, 404, 405 Angiospermm, (Case-seed Class), 8 Angiospermous gynoecium, 392 Angiosperms, 397; as dominating plants, 560; evolution of, 538 Aniline dyes, 290 Animal, fibers, 223; kingdom, 561, 562 Animals and plants defined, 573, 574 Animals evolved from plants, 466 Anise, 137, 142, 170, 370, 412, 413 Annual herbs, 333; rings, 253 Annuals, 352 Annulus, 529 Anther, 12, 14, 319, 550 Antheridia, 515, 516, 517, 527, 637 Antheridia-carriers, 516 Antheridiophores, 516 Anthers dehiscing by longitudinal slits, 354, 355; by uplifted valves, 360; poricidal, 379; syngenesious, 384 Anthoceros Icevis, Horned-liverwort .4 nthocerotacece. Horned-liverwort Family Antiseptics, 177 Apetalous flowers, 349 Aphorism of Linnaeus, 561; re- vised, 574 Apium grareolens, Celery Apoc.ijnaccce, Dogbane Family Apothecium, 505 Appendages for disseminaticjn, 5()0 Apple, 86, 87, 88, 121, 124, 363, 408, 409; pulp, 114; wood, 269 Aquatic ancestry of fernworts, 550 Aquifoliacece, Holly Familj'^ Aquilegia vulgaris. Columbine Arabin, 163, 164 Arabinose, 164 Araceoe, Arum Family Arachis hypogcea, Peanut .4ra/es, Arum Order Araliacece, Ginseng Family Archegonia-carriers, 518 Archegonia, rutlimentary, 556 Archegoniophores, 518 Archegonium, 514, 528, 537, 551 Archichlamydeos, Crowfoot Series Archichlamydeous flower, 378 Aril, 213, 393 Arrhenius, Svante, 568 Arrow-poison, 189 Artemisia Absinthium, Wormwood Artichoke, Jerusalem, 43, 61, 62, 120, 125, 385, 420, 421 Articles of dress, 284 Artificial, cell, 563; feeding, 563; lightning, 168; limbs, 245; 280; selection, 446, 447, 455; silk, 224, 228; svstems, 307 Arum Family, 389, 397, 422, 423: sweet-flag, 174 Arum Order, 389, 397, 422, 423 Asafetida, 170, 172, 173, 175, 287, 370, 412, 413 Ascolichenes, Spore-sac Lichens Ascomycetes, Spore-sac Fungi Ascospore, 501 Ascus, 501 Ash, in coal, 300; in foods, 114; in grains, 30; in peat, 300; in wood, 298, 300 Ash, splints, 241; white, 259; wood, 562, 259 Asparagus, 55, 64, 65, 114, 120, 124, 390, 424, 425 Asparagus officinalis, Asparagus Aspen, American, 264 Aspidium Filix-mas, Mule-fern Astragalus gummifer, Tragacanth Shrub Astringents, 154, 166 I INDEX 579 All numbers refer to pages, heavy type indicating illustrations. Atavism, 43G Atropa Belladonna, Belladonna Atropine, 182, 186 Attar of roses, 150 Authority, 7 Arena saliva, Oats Awn, 13 Awnings, 223 Ax handles, 286 Axil, 319 Axile placenta, 355 Bacillus subtilis. Hay Bacillus Bacteria, 492, 511 Baderiacece, Rod-germ P'amily Bacterium, 574 Bacterium aceti, Vinegar P"'erment acidi lacfici, Milk-souring Bac- terium Bagging, 230, 232 Balls, 245, 277 Bamboo, 232, 235, 239, 274, 291, 387, 420, 421 Bambusa vulgaris, Bamboo Banana, 88, 98, 99, 121, 124; pulp, 114 Banana Family, 397: banana, 98, 99; Manila hemp plant, 233 Banana Order, 597 Baneberry, 328-356, 334, 335, 404, 405 Barberry Family, 398 Bark, 252; origin, 254 Barley, 11, 15, 25, 120, 124, 126, 156, 235, 387, 420, 421; com- mon, 21; kernel, 114; range, 26; six-rowed, 22; two-rowed, 22 Barrels, 263 Base-ball bats, 245 Basidiolichenes, Spore-base Li- chens Basidiomyceies, Spore-base Fungi Basidium, 502, 503 Basketry, 223, 235 Baskets, 241 Bass wood, 263 Bast fibers, 224, 228 Bats, 245 Bayberry Family, 398 Bayberry Order, 398 Bay, Bull, 262 Bean, 40, 270, 365, 408, 409; kid- ney, 49; Lima, 51 Beard-lichen Family: beard-lichen, 507, 508 Beard, of grasses, 13 Bee plants, 303 Beech, 414, 415; European, 268; wood, 257, 268 Beech Family, 374, 398, 414, 415; chestnut, 37; cork oak, 277, 278; Enghsh oak, 258; Euro- pean beech, 268; red oak, 257 Beech Order, 376, 398, 414, 415 Beer, 156, 495 Beet, 43, 52, 53, 120, 124 Beet-sugar, 102 Beggar sores, 217 Beginnings, many, 433 Belladonna, 186, 187, 208, 382, 416, 417 Bellflower, 384, 418, 419; creeping, 381 Bellflower Family, 384, 401, 420, 421: creeping bellflower, 381; Indian tobacco, 201 Bellflower Order, 386, 401, 420, 421 Bellflower Series, 386, 397 Belts, 223 Bent embryo, 363 Berberidacece, Barberry Family Berry, 351 Berry-like fruit, 392 Bertholletia excelsa. Brazil-nut Beta vulgaris, Beet Belula alba, White Birch Betulaceoe, Birch Family Beverage plants, 128 Biennial, 52, 333 Bignoniacece, Bignonia Family Bignonia Family, 401 Bilabiate calyx, 366 Billiard cues, 245 Binomial nomenclature, 4 Binders' boards, 224 Biological botany, 10 Birch, 373, 412, 413; oil of, 297; white, 265; wood, 257, 263 Birch Family, 373, 398, 414, 415; filbert, 36; white birch, 265 Bird's eye maple, 263 Bisexual thallus, 514 580 INDEX All numbers refer to pages, heavj^ type indicating illustrations. Bitter Cassava, 104, 110, 111, 121, 124 Bittersweet, 209, 212 Black, dye, 294; iiuistard, 133, 134; nightshade, 208, 212; i)ep- lK>r, 12S, 131, i'AV), 177; pepp(T oil, 130; pigments, 294; walnut, 260, 376 Bladderwort Family, 401 Bladder-wracks, 4S7, 488, 489 Blade, 336, 537 Blanc-mange, Irish moss, 107 Blossom, 343 Blue Alga?, 470, 492, 508 Bluebell type of flowers, 435 Boats, portable, 284 Body of ovule, 346 Bone substitute, 276 Boot-soles, 287 Borage Family, 401 Boraginaccoe, Borage Family Borecole, Garden Kale Botanical pictures, 312; ques- tions, 1 Botany, as a study of names, 314; beginnings, 1; departments of, 8; science of, 1; systematic, 314, 315 Bolrychium Lunaria, Grape-fern Botrj'ose inflorescence, 344, 345, 352 Bottle-gourd, 275, 383, 418, 419 Bowling-alleys, 245 Boxes, 243, 263, 268, 270 Brace root, 23, 299 Bract, 13, 343, 352, 354 Bractlet, 343, 352, 354 liraiding, 223 Branch, 428 Brandy, 159 Brassica campeslris, Turnip nigra, Black Mustard oleracea, var. ncephnla, Garden Kale and Tree-cabbage oleracea, var. Botrylis, Cauli- flower oleracea, var. capitata, Common Cabbage oleracea. var. qemmifera, Brus- sels Sprouts oleracea, var. gotujijlodcs. Kohl- rabi oleracea, var. sabauda, Savoy Cabbage oleracea, var. sylventris, Wild Kale Brazilian Rubber-tree, 281 Brazil-nut, 35, 44, 120, 125, 282; kernel, 114; slielLs, 282 Brazil-nut Family, 400 Bread raising, 495 Breathing-pores, 519, 529 Breeding, 430 Bridges, 270 Bromeliaccoe, Pineapple Family Brood-body, 514, 521 Brood-bud, 540, 542 Brood-cup, 521 Broom-corn, 232, 235, 236, 387, 420, 421 Brooms, 223, 235 Brown Algte, 485 Brushes, 223; whisk, 235 Brussels sprouts, 55, 69 Bryophyta, Brj^ophyte Division Bryophyte Division, 530 Bryophytes, 395, 39(5 Buckthorn Familv, 399 Buckthorn Order,"' 399 Buckwheat, 11, 29, 120. 125, 126, 372, 412, 413; climbing, 556; kernel, 114 Buckwheat Family, 372, 398, 412, 413: buckwheat, 29; climbing buckwheat, 556; garden rhu- barb, 104; medicinal rhubarb, 170 Buckwheat Order, 372, 398, 412, 413 Budding, reproduction by, 495 Buds, 319, 320; reproduction bv, 540, 542 BufTers, 280 Building, 222, 263 Buildings, 242 Bulb, 43; solid, 336 Bull Bay, 262 Burlap, 223, 230 Burr of chestnut, 38, 375 Butter bacteria, 494 liuttercup, 216, 443; at the sea- shore, 462; evolution of aquatic form, 467; pigmy, 444 Buttercups, 217, 328-356 INDEX 581 All numbers refer to pages, heavy typo indicating illustrations. Butternut, oo, 40, 120, 12"), :i7(\; wood, 261 Button-molds, 244 Buttons, 277 Buttonwood, 267, 268 Cabbage, 55, 120, 124, 274, 406, 407; common, 69; leaves, 114 Cabbages, etc., 362 Cabinet woods, 266, 26cS, 274 Cabinet work, 259, 261, 266, 270 Cables, 223, 235 Cacao, 103, 107, 108, 121, 124, 150 Cacao-butter, 167 Cactus Family, 400 Cactus Order, 400 Caffeine, 150, 153, 154 Calnniites ranwsus, Giant Scour- ing Rush Calamus, 170 Calamus spp., Rattans Calisaya-tree, 188 Calking, 223 Calories in foods, 114 Calory, 116 Caltha palustris, Marsh-marigold Calycanthacece, Strawberry-shrub Family Calyptra, 515, 520, 526, 528, 529 Calyx, 29; bilabiate, 366; gam- osepalous, 366 Cambium, 252, 254, 542 Campanula rapunculoides, Creep- ing Bellflower Campatiulacece, Bellflower Family Ca>npattulalcs, Bellflower Order Camphor, 177, 228, 360 Camphors, 177 Camjjylotrnpous ovule, 363 Canal-cells, 544 Candles, 288 Canes, 245, 268, 274 Cane seats, 235 Cane-sugar, 101, 102 Cannabis saliva, Indian Hemp Canning, 157 Canoes, paper, 224 Cantaloup, Muskmelon Canvas, 230 Caoutchouc, 280, 281 Caper-bush, 145, 146 Caper I'aniilv, 398: caper-bush, 145, 146 Capers, 137 Caper Spurge, 216, 217 Capitate inflorescence, 373 Capparidaceoe, Caper Family Capparis spinosa, Caper-bush Cap of musljroom, 502 Caprifoliaceo', Honeysuckle Fam- iiy Caps, 239 Capsdla Bursa-pastoris, Shep- herd's Purse Capsicum annuum, Red Pepper Capsule, 351, 515; enveloped loculicidal, 379; loculicidal, 368 marginicidally septifragal, 382 poricidal, 362; septicidal, 379 septifragal, 382 Carawav, 137, 142, 170, 297, 370, 410, 411 Carbohydrates, 31, 74, 114, 115 Carbon, 570 Carbonaceous foods, 115 Carbon dioxid, 68 Carbon filaments, 228 Carbonic acid gas, 68 Carboniferous period, 299 Cardamoms, 137, 141, 170 Cardol, 218 Carpel, 346, 352, 550, 551 Carpellary leaves, 352, 555 Carpentry, 242, 256, 271 Carpets, 230 Carpospore, 490 Carrageen, 105, 112, 121, 125, 163, 165, 395, 487, 491 Carrageen Familv: carrageen, 112, 491 Carriages, 259, 260, 263 Carrot, 43, 55, 56, 57, 120, 124, 219, 370, 412, 413; wild, 430 Cars, 256, 259 Carum Carui, Cara,way Carving, 242, 257, 263, 269, 280 Car-wheels, paper, 224 Carya alba, Hickory, Shagbark Carya olirrrformis, Pecan Carynplij/llaccfc, Pink Family Caryop.sis, 388 Case-seed Class, 8, 391, 397 Case-seedworts, Case-seed Class 582 INDEX All numbers refer to pages, heavy type indicating illustrations. Casks 243 Cassava, Bitter, 104, 110, 111, 124 Castanea sativa, Chestnut Castile soap, 296 Castor-oil, 167 Castor-oil plant, 172, 173, 213 Catabolism, 85; imitated, 563 Catkins, 373 Caulicle, 317, 318, 319, 557 Cauliflower, 55, 70 Cedar, Red, 273, 392; oil of, 297; wood, 270 Celery, 55, 75, 114, 121, 124, 137, 370, 412, 413 Cell, 473, 560; artificial, 563 Cell-contents, 473 Cell-division, 510 Cell-masses, 560 Cell-multiplication, rapidity of, 511 Cell-plates, 560 Cell-rows, 560 Cells, mostly minute, 511; of large size, 510 Cellular cryptogams, 396 Celluloid, 224, 228 Cellulose, 32, 276, 472; products, 223, 224 Cellulose covering, protective and permeable, 575 Cell-wall, 473 Cement for leather, 287 Cements, 288 Central cylinder, 528 Cerealia munera, 11 Cereals, 11-34 (see aho Grains); the principal, 15; value of, 30 Ceres, 11 Celraria islandica, Iceland Moss Chaff, 11 Chain, family, 355 Chairs, 223 Chair seats, 241 Characteristic adaptations, 442 Characters, acquired, 443 Charcoal, 29S, 300 Chart, Food, 114 Checkerberry, 203 Checkers, 245 Cheese bacteria, 494 Chemical botany, 9; composition of foods, 114 Chemico-i)hysical properties of living protoplasm, 571 Chenopodiaccd, (J!o(jsefoot Familj' ChenopodUdc.-i, Goosefoot Order Chermes ahiclis, iSpru(-e Aphis Cherry, 8S, 90, 121, 209, 364, 408. 409; poisoning by leaves, 203; })oisoning by stones, 205; wild black, 260; wood, 263 Chessmen, 245 Chestnut, 35, 37, 38, 120, 124, 294, 374, 414, 415; kernel, 114; wood, 257 Chests, 260 Chili Pepper, 132 China-tree Family, 399 Chip, 241 Chlorophijcece, Green Alga? Chlorophvll, 67, 74, 471, 476, 485, 487, 573 Chocolate, 102, 154 Choice, in plants and animals, 463; power of, 568; the pivotal factor in evolution, 469 Chondrus crispus, Carrageen Choosing the better way, 468, 469 Choripetalous corolla, 379 Christmas Holly, 212; Rose, 330, 331, 328-356, 404, 405 Chromatophore, 476 Chroucoccacea>, Tint-ball Family Chroiicoccus turgidus, Tint-ball Alga Cicuki maculata, Water Hem- lock Cinchona Calisayn, Calisaya-tree Cincinnobolus, 500 Cinnamomum Camphora, Laurel- camphor Tree zeijlanicum, Cinnamon Cinnamon, 128, 135, 177, 360, 406, 407 Cistacea, Rock-rose Family CitruUus vulgaris, Watermelon Citrus Aurantium, Orange m,edica, var. Limonum, Lemon Class, 8, 428 Classes, Linnajan, 308 Classification, 305; bj^ size, 306; by uses, 306; early attempts, 306; expressing kinship, 433 Cleanliness, 494 INDEX 583 All numbers refer to pages, heavy type indicating illustrations. Clematis, 404, 405; erect silkv, 337, 328-356; evolution of, 444, 445, 449, 457; mountain, 335, 328-356; vine-bower, 336, 328- 356 Clematis alpina, Mountain Clem- atis Vitalba, Vine-bower Clematis Climbing Buckwheat, 55*? Climbing-ferns, 299 Climbing habit, evolution of, 455 Close-fertilization, 512 Clothes-pins, 259 Cloves, 128, 129, 177 Cloves, oil of, 129, 130 Club-moss, 167, 174, 326, 394, 544 Club-mosses, 544; giant, 299, 301 Club-moss Family, 554: club- moss, 174 Coal, 298, 300, 549; age, 547 Coalescence of floral organs, 354 Coalescent floral organs, 350 Coal plants, 299, 432 Coal-tar, 290 Coca, 182, 185, 186, 187 Coca Family, 399: coca, 185, 187 Cocoa, 102 Cocoa-butter, 296 Cocoanut, see Coconut Coconut, 35, 46, 47, 120, 124, 296, 388, 422, 423; dipper, 276; ker- nel, 114; oil, 296, 297; palm, 46, 47, 235, 274 Cocos nucifera, Coconut Coffea arahica, Coffee Coffee, 150, 153, 154, 155; aroma, 154 Coffee-sacks, 230 Cogs, 245 Cohesion figures, 129, 130 Coir, 232, 235 Coke, 298, 300 Coleochcetacca;, Sheath-alga Family Coleochcete soluta, Free-branching Sheath-alga Collodion, 224, 228 Colonies, 510 Colophony, 288 Coloring matters, 222, 290 Colors of flowers, 557 Columbine, 328-332, 333, 334- 356, 404, 405 Columbus, Christopher, 283 Columella, 519, 529 Column, 149 Combs, 284 Commelinacea, Spiderwort Family Common, cabbage, 69; • cherrv, 121, 124; currant, 94; field mushroom, 107; pea, 120 Companion-cells, 556 Compass plant, 73 Complete flower, 42, 349 Composilce, Composites Composites, 311 Compound cyme, 344 ; flower, 385 ; inflorescence, 345, 352; leaf compared with leafy shoot, 342; leaves, 339, 352; pistil, 347 Concave torus, 355 Conceptacle, 487 Condiments, 128; miscellaneous, 137 Conduction, 528 Cone-like fruit, 374 Cone of scouring-rushes, 543 Cones, 547 Cone-scales, 548 Conflicts destroy or test, 468 Coniferce, Conifers (md Pine Order Coniferales, Pine Order Conifers, 311; evolution of, 554 Conium maculatum, Poison Hem- lock Conjugating-cells, 497 Conjugation, 478 Connecting Imks, 402, 440, 449, 456 Consumption, 494 Contrast of vegetable with human life, 575 Convallaria majalU, Lily-of-the- valley Convex torus, 355 Convolute ajstivation, 369 CoNi'oZ?mZace(E, Morning-glory Fam- ily Cooking, 297 Cooperage, 243, 258, 259. 260, 261, 268, 270 Co-operative provision for off- spring, 511 Copal, 288, 290, 296 Copal-tree, Zanzibar, 366, 408, 409 584 INDEX All numbers refer to pages, heavy type indicating illustrations. Copper sulphate for killing algai, 476 Cora pavonia, Mushroom-lichen Corchorus capsularis, Fodded Jute olitorius, Pot-herb Jute Cordage, 223, 230, 232, 23-5 Cord-moss, 522, 526, 527, 528, 529 Cord-moss Family : cord-moss, 526-529 Cords, 223 Cordaites, 299, 554 Core of pome, 365 Coriander, 137, 143, 144, 370 412, 413; oil of, 297 Coriandruin sativum, Coriander Cork, 222, 279; mother, 278, 279; oak, 277. 278 Corm, 336 Cornacew, Dogwood Family Corn, Indian {sec Maize) Corolla, 43; choripetalous, 379; gamopetalous, 379; labiate, 383; papilionaceous, 366; strap- shaped, 385 Corolla, parts of, keel, 366; stand- ard, 366; wings, 366 Correlated characters, 451 Cortex, 530, 538 Corylus Avellana, Filbert Corymb, 345 Corymbose inflorescence, 345, 352 Cosmarium Botrys, Grape Des- mid Costate, 341 Cotton, 224, 225, 226, 227, 369, 410, 411; absorbent, 228; bag- ging, 230; batting, 22S Cotton-seed oil, 100, 296, 297 Cotyledon, 46, 48, 317, 318, 319, 546, 557 Courbaril-tree, 289, 290, 366, 408, 409 Coverings, waterproof, 284 CrnssulacecE, Orpin(> Family Crates, 243, 263, 270 Creation, special, 429 Creationism, 429 Creator as architect, 431 Creeping Bellflower, 381 Cremocarp, 371 Creosote, 300 Cricket-bats, 245 Crocus saliincs, Saffron Crocus Croquet-mallets, etc., 245 Cros.s-fertilization, 512, 557 Cross-partitions in hj'pha), 499 Crowfoot, 217, 328-356, 404, 405; white water, 467 Crowfoot Family, 328, 330, 3.58, 360, 398, 404, 405: baneberry, 334, 335; Christmas rose, 330, 331; columbine, 333, 334; ditch crowfoot, 216; erect silky clem- atis, 337; marsh-marigold, 198; monkshood, 191; mouse-tail, 330, 331, 332; mountain clem- atis, 335; pasque-flower, 338; peony, 329; pigmy buttercup, 444; seaside crowfoot, 463; tall buttercup, 216; vine-bower clematis, 336; white water crow- foot, 467; wood-anemonv, 205 Cro^\'foot Order, 361, 398, 406, 407 Crowfoot Series, 377, 386, 397 Crowfoot type of flower, 435 Crown-tuber, 43 Crozier-like vernation, 537 Cruciferce, Mustard Family Crude rubber, 2S3 Crutches, 245 Cryptogamia, Cryptogams Cryptogams, 308; cellular, 396; vascular, 396 Cryptogams and Phenogams, 5.50 Crvstalwort Familv: crvstalworts, 513, 515 Crvstalworts, 513, 515 Cucumber, 82, 83, 121, 124, 383, 418, 419; fruit, 114; .sponge, 383 Cucumis Melo, Muskmelon sativus, Cucumber Cucurbita maxinin, Hubbard Squash and Turban Squash ni.oschata, Winter Crook-neck squash Pepo, Pumpkin, Long WTiite Squash, Summer Crook-neck Squash, and Scallop Squash Cucurbitales, Gourd Order Cuciirbitacc(r, Gourd Family Culture-period and nati\-e. home, 123, 125; of food-plants, 120 Cupule, 375 INDEX 585 All numbers refer to pages, heavy type indicating illustrations Curly maple, 263 Currant, 88, 94, 121, 125 Cyainophycece, Blue Algic Cycad, 558; Japanese, 555 Cycadaceoe, Cycad Family Cycadales, Cycad Order Cycad Family: 397; Japanese cycad, 555 Cycad Order, 397 Cycads, 554; evolution of, 558 Cycas revoluta, Japanese Cycad Cycles of life, 470 Cydonia vulgaris, Quince Cyme, 344 Cymose inflorescence, 343, 344, 345, 352 Cyperaceoe, Sedge Family Cypripedium hirsidiuu, Showy Ladies' Slipper parviflorum, Yellow Ladies' Shp- per Cytoplasm, 473 Daily ration, 117, 118 Dandelions, 442, 443 Daphne, 205, 209 Daphne Mezereum, Daphne Darwin, Charles, 446 Darwinism, 446, 453, 456, 457; objections to, 452 Date, 88, 100, 101, 114, 121, 124, 388, 422, 423 Date-palm, 274 Datura Stramonium, Jimson-weed Daucus Carota, Carrot Dead substances, 570 Death, 572 Death-cup, 214, 215 De Candolle, Augustin Pyrame, 316 Decay, 494, 504 Decompound leaves, 339, 352 Decoration, 223 Definite variations, 448 Degeneration, 468, 512; in ferns, 535 Dehiscence of anthers, 354; by longitudinal slits, 355; by pores, 379; by uplifted valves, 360 Dehiscence of fruits, 351; dorsal, 359; loculicidal, 368; margin- icidally septifragal, 382; pori- cidal, 362; septicidal, 379; septi- fragal, 382; ventral, 351 Dentists' absorbent, 239 Departments of botany, 8 Description, early attempts, 312; Linnieau ideal, 314; in "ordi- nary English," 312; technical, 312 Desert plants, 454 Desmidiacea;, Desmid Family Desmid Family: grape desmid, 477 Desmids, 476 Determinate inflorescence, 343, 352 Devil's Aprons, 485 Diadelphous stamens, 366 Diastase, 32 Dicots, 397 Dicotyledonous embryo, 386 Dicotyl Subclass, 397 Dietary standards, 117 Diet, mixed, 118; well-balanced, 118 DifTerence between animals and plants, 573 Digitalis purpurea, Foxglove Dioecious inflorescence, 360 Dippers, 276 Diseases due to fungi, 504 Disk, 61 Dispersal of seeds, 560; of spores, 511, 532 Dissemination, 560; organs of, 322 Distillation, 128 Distilled beverages, 159 Distinct floral organs, 350, 354 Ditch Crowfoot, 216, 328-356 Divided leaves, 339 Diving-dresses, 284 Division, 8 Division of labor, 321 Divisions of vegetable kingdom, 394, 396 Dogbane Family, 401; oleander, 206, 207 Dogwood Family, 400 Domesticated varieties, 430 Domestication, 446 Domestic utensils, 243 Door-mats, 235 Dorsal dehiscence of pericarp, 359; placenta, 346 Double flowers, 347 586 INDEX All numbers refer to pages, heavy type indicating illustrations. Drawing-paper, 224 Drawers, 263, 26S Drugs, ]63; poisonous, 176 Drupaceous, fruit, 365; nut, 376 Drupe, 364 Dry, cooperage, 243; fruits, 351; pericarp, 3ol, 355 Drying oils, 295 Duck, 230 Dugout canoe, 247 Dust-spore, 496, 49S, 505, 511 Dust-spore-case, 496 Dyeing, 222 Dyers' Indigo Shrub, 292, 293 Dyestuffs, 290 Early attempts at classifying, 306; at describing, 312 Ear of grain, 11 Earth- vegetables, 35, 41 Ebenales, Ebony Order Ebony Order, 401 Ebracteate inflorescence, 362 Ecological botany, 10 Economic, botany, 9, 304; impor- tance of fungi, 504; properties of plants, 575 Economics of co-operation, 468 Egg-apparatus, 556 Egg-cell, 514, 521, 551, 552, 556, 557, 560 Egg-plant, 85, 121, 124, 382 Egg sac members, 352 Egg-sacs, 325, 326 Egg-spore Alga?, Evolution of, 558 Elastic, bands, 284; gums, 222, 280, 287; springs for dissemina- tion, 560; webbing, 283 Elater, 517, 620, 526, 541, 543 Elder, 196, 197, 202, 208 Ele(;tric apparatus, 288 ElclUiria cardamomum, Carda- moms Elm, 259; American, 259; bark, 163; English, 166; wood, 256, 259 Elm Family: 398; American elm, 259; English elm, 167 Elm-leaved Linden, 264 Embryo, 29, 48. 3Ui, 317, 318, 351, 352, 514, 553, 556; bent, 363; curved, 362 ; dicotyledonous, 386; monocotj'ledonous, 3SS; uncoiled, 355; of fern, 538 Embryo, i)arts of; cotyledon, 46, 48; plumule, 48; radicle, 48; scutellum, 3SS; seed-bud, 48; seed-leaf, 46, 48; seed-root, 48 Embryos, 547 Embryo-sac, 551, 556 Endogenous stems, 387 Endosperm, 551 Endospore, 478 Energy, in food, 114; measures of, 115; of vegetable foods, 116 Engler and Prantl's classification, 394 English, elm, 165, 167; oak, 258; walnut, 261, 296 En^aronment, 431 Enzyme, 32, 494 Epidermis, 254, 530, 538, 640, 542 Epicalyx, 364 Epigynous flower, 365 Epiphyte, 508 Equisetacea, Hcouring-rush Fam- iiy Equisetinop, Scouring-rushes Equisetum arvense, Scouring-rush Erasers, 284 Erect Silkv Clematis, 328-336, 337, 338-356 Ericacea:, Heath Family Ericales, Heath Order Erysibe communis, Powdery-mil- dew Erythroxylacecp, Coca Family ErythroxyJon Coca, Coca Essence of life, 568, 569 Essences, 128, 146 Essential organs of flower, 13, 43, 319 Ethers, 159 Euphorhincece, Spurge Family Euphorbia Lathyris, Caper Spurge marginata, Snow-on-the-moun- tain European, beech, 268; grape, 88, 93, 121, 124; larch, 271; rasp- berry, 91 Evening-primrose, 457 p]vening-i)rinirose Family, 400 Evolution, 433; by choice, 461, 464; in general, 464; of clematis, INDEX 587 All numbers refer to pages, heavj^ type indicating illustrations. 444, 445, 449, 4.52, 457; of crow- foot family, 437, 438; of fern- worts, 548, 549; of flowering plants, 559, 560; of human so- ciety, 468; of mankind, 468, 469; of mossworts, 531; of ovaries, 557; of plants, 560; of scour- ing-rushes, 543; of seed-plants, 658, 559, 560; of thallophytes, 510; of the universe, 464; of vegetable kingdom, 466 Exalbuminous seed, 363, 557 Excelsior, 241 Exogenous stems, 387 Exospore, 478 Exstipulate leaf, 359 Extinct, branches, 449; types, 467 Extinction, 467, 468 Ej-e-spot, 482 Fabrics, 223 Factors of change, 468 Fagacece, Beech Family Fagales, Beech Order Fagopyrum esculentum, Buck- wheat Fagus sijlratica, European Beech Fallen Stars, 473, 474 Family, 7, 403; chain, 355; tree, 436, 437 Famine, effect of, 463 Fans, palm-leaf, 388 Farm implements, 256 Fat, 34; in foods, 114 Fats, 74, 114, 115 Feeding, imitation of, 563 Feehng, 573; in plants and ani- mals, 562 Fence rails, 258 Fences, 245, 260 Fennel-flower, 328-332, 333-341, 342-356, 404, 405 Fermentation, 156, 494 Fermented beverages, 156 Fern prothallium, 536 Ferns, 308, 311, 532; climbing, 299; evolution of, 558; fossil, 534; herbaceous, 535 Fernworts, 394, 396, 548 Fertility of hybrids a test of spe- cies, 430 Fertilization, 484, 552; in angio- sperms, 555, 556; in gymno- sperms, 551-555 Ferula assa-faetida, Asafetida Plant Fiber-plants, 224 Fibers, 222, 224; animal, mineral, and vegetable, 223 Fibrils, 250 Fibrovascular bundles, 394, 533, 538, 539, 540 Ficus carica, Fig elastica, India Rubber-tree Field Mushroom, 113, 121, 125, 395, 501, 502, 503 Fig, 88, 102, 121, 124 P^igwort Family, 382, 401, 416, 417: foxglove, 204 Filament, 12, 14. 319 Filbert, 35, 36, 120, 124, 373; ker- nel, 114 Filices, Ferns Filicina, Ferns Filling, 223 Finishing lumbers, 263 Fireworks, 168 First of li\'ing things, 466, 566, 567 Fission, 473, 560 Fission-algae, 558 Fission fungi, 492; descendants of fission-alga», 495 Fishing-rods, 274 Fish-lines, 223 Fixed mode of life in plants, 575 Fixed oil, 34; of black mustard, 134; of white mustard, 134 Fixed oils, 128, 166, 295 Fixity, in animals, 573; of species, 429, 430 Flagellum, 482 Flavoring plants, 128 Flax, 224, 229, 231, 345, 435; as a type, 316; bud, 319, 320; ger- mination, 317, 318; plant, 229, 230, 231, 334 Flax Family, 399: flax, 229, 231 Flaxseed, 163, 164, 295, 318 Fleshy, fruits, 351; pericarp, 351, 355; torus, 364 Flint in epidermis, 542 Floats, 279, 280 Floor covering, 280 Flooring, 263, 270 INDEX All numbers refer to pages, heavy type indicating illustrations. Floral envelops, 319 Floral organs, adhesion of, 3(55; arrangements for pollination, 557 Floral organs, alternate, 350, 354; coalescent, 350; distinct, 350, 354; epigynous, 365; free, 350, 354; hypogynous, 350; inser- tion of,' 349; opposite, 368; par- tially coalescent, 354; perigy- nous, 350 Florets, 380 Flower, 319, 557 Flower-cluster, 343 Flower in the crannied wall, 576 Flower, parts of: androecium, 346; anther, 12, 14; calyx, 29; car- pel, 346; corolla, 43; epicalyx, 364; essential organs, 13, 43; filament, 12, 14; funicle, 346; gyncpcium, 346; keel, 48; mi- cropyle, 346; nectar, 29; nectar- gland, 29; nectar-leaves, 34S; ovary, 12, 14, 345; ovule, 12, 14, 346; pappus. 386; perianth, 43; petal, 42, 348; pistil, 11, 14, 345; placenta, 346; raphe, 346; receptacle, 349, 385; sepal, 29; silk, 24; stamen, 12, 14; st ami- nodes, 348; standard, 48; .stigma, 12, 14, 345; .style, 12, 14, 345; torus, 349, 350; wings, 48 Flowering plants, 393, 396, 397; evolution of, 559 Flowers, attractions of, 557 Flowers, apetalous, 349 ; archichla- mydeous, 378; axillary, 345; clustered, 352; complete, 42, 349; compound, 385; double, 347; epigynous, 365; imperfect, 13, 347; irregular, 349, 354; metachlamydeous, 386; neutral, 371; perfect, 13, 347, 353; pis- tillate, 347; polygamous, 347; regular, 354; resupinate, 391; rudimentary, 13, 14; solitary, 345; solitary axillary, 352; soli- tary terminal, 352; staminate, 347 Fluctuating variations, 448, 455 Flux, 288 Fly-amanita, 215, 217 Fly-poison, 217 Fodder, 303 Foliage, as a sunbeam-trap, 302; main work of, 85 Foliage-plants, 303 Follicle, 351 Fomes fomentariiLs, Amadou Food, 128; as fuel and building ma- terial, 114; chart, 114; favorite combinations, 119 Food-adjuncts, 128, 159, 302 Food-making, 74 Food-plants, 122; classes of, 35; native home and culture period, 120, 121 Food-products, miscellaneous, 91 Foods, 302; vegetable, 113; vege- table versus animal, 119 Foot of sporophyte, 517, 538 Footstalk, 336 Forests, effect on water-supply, 304 Form blocks, 263 Formative material, 254, 320 Formulas, plant, 352; of .seed- plants, 404-427 Fossil, botany, 10; club-mos.s 301; ferns, 534; scale-tree, 301 Fossils, 432 Fountain pens, 284 Foxglove, 204, 208, 382, 416, 417 Fox-grape, 125 Fragaria spp., Strawberry Fraxiniis americnna, White Ash Free-branching Sheath-alga, 483 Free floral organs, 350, 354 Free will, 568, 569 French Rose, 160 Fruit, 12, 319, 350; cone-like, 374; dehiscent, 351 ; drupaceous, 365; dry, 351; fleshy, 351; indehis- cent, 351 Fruit-bod V, 500, 501, 502 Fruit, parts of: aril, 213, 393; burr, 38; chaff, 11; grain, 12; husk, 11, 12; kernel, 11; peri- carp, 351; pit, 89; seed, 350; .stone, 89, 364; suture, 351 Fruits, 35, 88: achene, 351, 386; berry, 351; berry-like, 392; cap- sule, 351 ; caryopsis, 388; cremo- carp, 371; cupule, 375; drupa- INDEX 589 All numbers refer to pages, heavy type indicating illustrations. ceous nut, 376; drupe, 364; fleshy torus, 3()4; follicle, 3ol; hip, 364; legume, 367; nut, 374; nutlet, 364; pepo, 384; pome, 365; samara, 3.5S; schizocarp, 370; silique, 363; stone-fruit, 364 Fruit-vegetables, 35, S5 Fucacecc, Wrack Family Fiicus vesicidosus, Bladder-wrack Fuels, 222, 279, 297 Fuel value of foods, 114 Funnriacecc, Cord-moss Family Funaria hijgrotnctrica, Cord-moss Function, 321 Fundamental system, 539 Fungal diseases, 504 Fungi, 589 (see also INIushroom Subdivision) Fungi, in general, 503; parasitic upon parasitic fungi, 501 Fimgus Subdivision, 395, 396 Funicle, 346 Furniture, 243, 257, 259, 263, 276 Gamboge, 290, 291 Gamboge Family, 400 Gamboge-tree, Siamese, 290, 291 Gametangium, 484 Gamete, 478, 512 Gametophyte, 485, 514, 515 Gamopetalous corolla, ;379 Gamosepalous calj'x, 366 Gaps, 449; limiting groups, 440 Garcinia Hanburyi, Siamese gam- boge-tree Garden, currant, 125; kale, 55, 68; rhubarb, 91, 104, 121 Garments, paper, 224; waterproof, .284 Gas, illuminating, 298 Gaultheria procumbens, Winter- green Gelatinous, substances, 163; ma- terial, 472 Genus, 6, 428 Gentianacece, Gentian Family Gentianales, Gentian Order Gentian Family, 401 Gentian Order, 401 Geographical botany, 10 GeraninceiB, Geranium Family Geraninles, Geranium Order Geranium Family, 399 Geranium Order, 399 Germ, 316, 352 Germs carried from plant to jjlant, 568 Germination of flax, 317, 318 Giant, club-mosses or lycopods, 299, 301, 547; scouring rush, 299 GigarUnncetp, Carrageen Family Giglio-Tos, E., 563 Gill-mushroom Family: death-cup, 215; field mushroom, 113; fly- amanita, 215 Gills of mushroom, 502, 503 Gin, 159 Gin, cotton, 228 Ginger, 128, 134, 136, 170; oil, 130 Ginger Family, 397: cardamoms, 141; ginger, 136 Ginkgoaccce, Ginkgo Family Ginkgo Family, 397 Ginkgo Order, 397 Ginkgoales, Ginkgo Order Ginseng Family, 400 Girths, 223 Glabrous, 343 Gliadin, 33, 34 Glucose, 31, 102 Glucosides, 292 Glumaceous perianth, 390 Glumes, 387 Glumiflorvp, Grass Order Gluten, 33 Glutin, 33 Glycerides, 296 Glycerin, 296 Glycyrrhiza glabra, Licorice God, immanence of, 569 Goethe's theory of flowers, 325 Golf, balls, 287; clubs, 245 Gonidium, 507 Goodyear, Charles, 283 Goosefoot Family: beet, 52, 53; spinach, 71, 72 Goosefoot Order, 398 Gossypium barbadense, Sea-island Cotton ; herbaceum, Upland Cot- ton Gourd, 121, 276, 276 Gourd Familv, 383, 398, 401, 418, 419: bottle-gourd, 275; 590 INDEX All numbers refer to pages, heavj' type indicating illustrations. cucumber, 82, 83; hubburd squash, 81; long white scjuash, 79; muskmelon, 95; pumpkin, 76, 77, 78; scallop squash, 80; summer crook-n(!(',k squash, 79; turban squash, 81; vegetable sponge, 240; watermelon, 96; winter crook-neck squash, 81, 82 CJourd Order, 401 Grains (see also Cereals) 11, 12; earliest use, 20; in ancient times, 17 Gramina, Grasses Craminales, Grass Order Grnmineoe, Grass Family Grape, European, 88, 121, 124; northern fox, 88, 93, 125; pulp, 114; sugar, 31 Grape Desmid, 477, 479 Grape Family, 399: grapes, 93 CJrape-fern, 532, 533 Grapes, 88, 93, 121, 157 Grasses, 11, 311 Grass Family, 387, 397, 422, 423: bamboo, 239; barley, common, 21 ; barley, six-rowed, 22 ; Barley, two-rowed, 22; broom-corn, 236; maize, 23, 24; oat, 12, 13, 14; rice, 16, 17; rye, 18; sugar- cane, 106; wheat, 19, 20 Grass Order, 388, 397, 422, 423 Gravitation and evolution, 441 Greek origin of terms, 313 Green Algaj, 47G, 508 Growing-points, 254 Growth, 561, 572; a slow behavior, 442 Guitars, 245, 270 Gum, 32, 287 Gum arable, 163, 164 (ium Arabic Tree, 163, 163, 366, 408, 409 Gum-resins, 287 Gum tragacanth, 164 Guncotton, 224, 228 Gunny bagging, 223 Gunpowder, 300 Gun-stocks, 261, 245 Gutta-percha, 280, 285 Gyrnnosperwtv, Naked-seed Class Gymnospermous gyna^cium, 392 . Gymnosperms, 397, 550 Gynoecium, 346; angiospermous, 392; gymnospermous, 392; naked-seeded, 392 Habit of plant, 359 Habits, 572 Ibcmatein, 292 Ibeinatoxylin, 292 Hdinaloxijlon campecheanum, Log- wood-tree Hair-like outgrowths, 538 Half-inferior ovary, 350 HamamelidacecB, Witch-hazel Fam- iiy Hamamelis mrginica, Witch-hazel Hames, 244 Hammocks, 223 Hampers, 223 Handles, 245, 280, 284 Hard, pine, 270; rubber, 284; soap, 296 Harmful plants, 302 Harness, 244, 259, 260 Hashish, 181 Hat linings, 280 Hats, 223, 238; chip, 241; straw, 235 Haustorium, 499 Hay Bacillus, 492 Hazel, 373, 412, 413 Hazelnut, 36 Head, 373; of grain, 11 Heart-wood, 246 Heath Family, 378, 401, 416, 417: mountain laurel, 202; sheep laurel, 202; wintergreen, 148 Heath Order, 379, 401, 416, 417 Heating, 297 Helianthus (uberosus, Jerusalem Artichoke Heliopsis scabra, Oxeye HpU chorus niger, Christmas Rose Helm inthocladiaceop, Thread-weed Family Hemlock, 273, 294, 392, 426, 427; poison, 194, 195, 209, 370; water, 193, 370; wood, 271 Hemp, 224, 230 Hemp, Indian, 193 Hemp, Manila, 232, 233 Hepaticoe, Liverworts INDEX 591 All numbers refer to pages, heavy type indicating illustrations. Hepatics, 511^ Herb, 330 Herbaceous, 333 Herbaceous Ferns, 535 Herbage-vegetables, 35, 53 Herbs, 306 Heredity, 572 Heterocyst, 474 Hevea guyatiensis, Brazilian Rubber-tree Hickory, 376, 414, 415; nut, 35, 120, 125; shagbark, 41; splints, 241; wood, 260 Higher dicots, 397, 401 Hip, 364 Hippocastanaceo', Horse-chestnut Family Hockey-sticks, 245 Hollv, 212 Holly Family, 399: Christmas holly, 212 Holophyte, 495 Homologies, 326, 327 Homologous parts, 326 Homologues, 326, 327 Homology, 326 Honey, 303 Honeysuckle Family, 401: elder 197 Hoops, 259 Hops, 156, 157, 170 Hordeum satirum, var. distichon, Barley, Two-rowed; var. hexas- tichon, Barley, Six-rowed; var. vulgare, Barley, Common Hormogonia, 475, 510 Horned-liverwort, 517, 522, 523 558 Horned-liverwort Familv: horned- liverwort, 522, 523, 558 Horn substitute, 284 Horsechestnut Family, 399 Horseradish, 137, 141, 144, 177, 362 Horticultural hybrids, 430 Hose, 284 Host, 211, 494 Hot springs containing algae, 475 House-furnishing, 223 Hubbard Squash, 81 Hubs, 259, 263 Human life contrasted with jilant life, 575 Human welfare dependent upon a knowledge of plants, 575 Humulus Lupulus, Hops Husk, 11, 235 Hybrids, 430 Hydrocarbon, 284; oxidized, 285, 287 Hydrogen, 570 Hymencea Courbaril, Courbaril- tree Hymenium, 503 Hypha, 496 Hypogenous floral organs, 350, 355 Hysterophyte, 495 Ice age, 432 Iceland Moss, 163, 165, 169, 395, 504, 505, 506, 507 Ignorance not to be argued from, 453 Ilex Aquifolmm, Christmas Holly Illicium anisatum, Star Anise Illuminating gas, 298, 301 Illuminants, 295, 297 Imbricate estivation, 349, 354 Imitation of feeding, 563; of \ital processes, 564 Immanence of God, 569 Imperfect flowers, 13, 347 Implements, 245, 259, 260, 263 Incandescent lamp filaments, 228 Indehiscent fruits, 351 Indeterminate inflorescence, 344, 352 India ink, 294 Indian, corn (.see Maize); hemp, 180, 181; poke, 199, 390, 424, 425; tobacco, 201, 202, 384, 418, 419 India-rubber, 283 India-rubber tree, 282 Indican, 292 Indigestible seeds for dissemina- tion, 560 Indigo, 290, 291, 562; blue, 292; white, 292 Indigofera tinctoria, Dver's Indigo Shrub Indigo Shrub, Dyer's, 292, 293, 366, 408, 409 502 INDEX All numbrrs rofor to jnigos, heavy tj'pc indicutins illustrations. Individual adaptations, 442; dif- fernnccs, 565 Individuality, 572 Induced variations, 448 Indusium, 179 Industrial implements, 245; plants, 222 Inferior ovary, 350, 365, 380 Infertile hybrids, 430 Inflorescence, 343, 352; amenta- ceous, 373; botryose, 344, 345, 352; capitate, 373; compound, 344, 345, 352; corymbose, 345, 352; cymose, 343, 345, 352; determinate, 343, 352; diwci- ous, 360; ebracteate, 362; in- determinate, 344, 352; monoe- cious, 374; paniculate, 345, 352; polygamous, 354; race- mose, 345, 352; simple, 352; spicate, 373 Inflorescence, parts of: awn, 13; beard, 13; bract, 13, 354; bract- let, 354; chaff, 11; disk, 61; glume, 387; husk, 11; involucel, 344; involucre, 61, 344, 354; lodicule, 13; rachis, 14, 344; re- ceptacle, 61; spathe, 388; spike- let, 13 Inflorescences, ament, 373; catkin, 373; cyme, 344; ear of grain, 11; head, 373; head of grain, 11; panicle, 345; raceme, 344; spa- dix, 388; spike, 373; umbel, 370; umbellule, 370 Inheritance of acquired charac- ters, 446; of acquirements, 443 Ink, 290; India, 294; printing, 294, 295; writing, 294 Inorganic, realm, 562; substances, 321, 570 Insect-pollination, 557 Insects attracted by sweets, 557 Insertion, 349 Insoles, 280 Insulating material, 287 Insulators, 284 Integuments of ovule, 551, 556 Intensity of the struggle for ex- istence, 453 lnterif)r finish, 257, 259, 261, 263, 268. 270 Internode, 317, 318 Interval cell-division, 495 Involucel, 344 Involucre, 61, 344, 354 Ipoma-a Batatas, Sweet Potato IridacecE, Iris F'amily Iris Family, 390, 397, 424, 425; saffron crocus, 176 Irish moss, 105, 112, 163, 165, 491 Iron and steel versus wood, 248 Irregular flowers, 349, 354 Ivory, Vegetable, 275, 276, 388 Ivy, Poison, 218, 219 Jamhosa CanjophyUus, Clove Japanese Cycad, 555 Jerusalem Artichoke, 43, 61, 62 120, 125, 385, 420, 421 Jimson-weed, 199, 200, 208, 210 382, 416, 417 Johnson Grass, 236 Joinery, 242, 260, 266 Juglan(iace(x, Walnut Family JuglananU's, Walnut Order Juglans cinerea, Butternut nigra, Black Walnut regia, Walnut Juice, acrid, 357; milky, 361; poisonous, 357 Junciis effunus, Rush Juniper, 158, 159, 392, 426, 427 Junipcrus conununis, Juniper virginiana. Red Cedar Jussieu, Antoine Laurent de, 311, 328; Bernard de, 311 Jute, 224, 230, 232, 367, 410, 411 Kale, 55, 120; garden, 68; wild, 66, 67 Kaleidoscope analog^-, 461 Kaltnia latifnlia. Mountain Laurel Keel, 48, 366 Keels, 263 Kelps, 485 Kidney Bean, 49, 50, 85, 114, 120, 124 Kilogrammeter, 116 Kingdom, 8, 428 Kingdoms, The Three, 561 King of dvestufTs, 291 Kinship, 403, 428 Knitting, 223 INDEX 593 All numbers refer to pages, heavy typ(> indiealinji; illustrations. Knobs, 269, 277 Kohlrabi, 55, 69 Lnhiatce, Mint Family Labiate, corolla, 383 Lace, 223, 230 Lacquer, 291 Lactuca satii'd, Lettuce scariola, Wild Lettuce Ladies' slippers, 218, 219, 220, 391, 424, 425 Lagenarin vulgaris, Bottle-gourd Lamarck ism, 445, 453, 456, 457 Lamarck, Jean Baptist e, 445 La miliar iaccoe, Sea-tangle Family Laminaria spp., Sea-tangles Lampblack, 290, 294 Larch, 294, 392, 424, 425; Euro- pean, 271; wood, 270 Larix decidua, European Larch Latin terms, 313 Lauraceoe, Laurel Family Laurel Camphor, 177, 228 Laurel-camphor Tree, 178 Laurel Family, 3(i0, 398, 406, 407:- cinnamon, 135; laurel-camphor tree, 178; sassafras, 168 Laurel, American, 41(), 417; moun- tain, 203, 379; sheep, 202, 379 Laurels, 208 Laurinol, 177 Law of recapitulation, 435, 560 Lead-pencils, 270 Leaf, 324, 336, 538 Leaf-buds, 323 Leaflets, 339, 342, 352 Leaf-member, 326, 327, 348 Leaf-part, 323, 325 Leaf, parts of, hgule, 16; rain- guard, 16; ocrea, 372; stipule, 358 Leaf -stalk, 336 Leafy shoot compared with com- pound leaf, 342 Leather, 295 Leather-finishing, 294 Leaves, 352, 533; alternate, 342, 352; carpellary, 352; compound, 342, 352; decompound, 352; ex- stipulate. 359; ocreate, 372; of the flower, 324; opposite, 342, 352; palmate, 3.52; parallel- veined, 3S7; pinnate, 352; i)ri- mary, 318, 319; rosette, 342; secondary, 318, 319; sessile, simple, 342; stipulate, 358; ternate, 352; verticillate, 342; whorled, 342 Legume, 367 Leguminosce, Pulse Family Lemon, 88, 97, 121, 124, 146, 170 Lemonade, 150 Lenlibulacea;, Bladderwort Family Lepidodendracea;, Scale-tree Fam- ily Lcpidodcndron {see also Giant Club-mosses, and Scale-tree), 547, 554 Lettuce, 55, 72, 73, 74, 121. 124, 385, 420, 421; leaves, 114; wild, 73 Lichen, 165 Lichenes, Lichen Subdivision Lichenin, 165 Lichens, 504 Lichens as Nature's pioneers, 506 Lichen-starch, 165 Lichen Subdivision, 395, 396, 508 Licorice, 163, 166, 169, 366, 410, 411 Lid of capsule, 526 Life, always existed, 568; essence of, 568, 569; test of, 568, 569 Life-cycles, 569 Life-histories, 470 Life-history of a molecule, 563 Lifeless substances, 570 Lifeless things versus living things, 569 Life-preservers, 280, 284 Lignin, 247 Ligule, 16, 547 Likeness a measure of kinship, 433 LiliacecB, Lily Family Liliales, Lily Order Liliiflorce, Lilv Order Lily Family, '390, 397, 424, 425: asparagus, 64, 65; Indian poke, 199; lily-of-the-valley, 204; on- ion, 63, 64 Lily-of-the-valley, 204, 208, 390, 424, 425 Lily Order, 390, 397, 424, 425 Lima bean, 51, 120, 124 504 INDEX All numbers refer to pages, heavy type indicating illustrations Lime in grains, 31 Lirtacece, Flax Family Linden, 263, 367, 410, 411 Linden, 362, 367, 410, 411; elm- leaved, 2d4 Linden Family, 367, 399, 410, 411 : elm-leaved linden, 264; jutes, 232 Linen, 230 Linnsean, reform in terminology, 313; Societv, 446; system, 308 Linna>us, 3, 308, 311, 312, 313; aphorism of, 561; revised, 574 Linoleic acid, 296 Linolein, 296 Linseed-oil, 280, 295, 296 Linum usitatissimum, Flax Liqueurs, 159 Liquors, 159 Liriodendron Tulipifera, Tulip Whitevvood Liverworts, 513, 530; evolution of, 558 Living beings, 562 Living substance, 570 Living versus lifeless things, 563 Lobelia inflala, Indian Tobacco Lobewort Division, 395, 396 Lobeworts, 509; 510 Locomotion of desmids, 478 Loculicidal dehiscence of capsule, 368 Locust, 196, 197, 208, 366, 408, 409; wood, 259; yellow, 259 Lodicule, 13 Loganiaceoe, Logania Family Logania Familv: nux vomica, 189, 190 Logwood. 290, 292 Logwood-tree, 294, 366, 408, 409 Long life of plants, 575 Long White Squash, 79 Loranthacece, IVIistletoe Familv Lower dicots, 397, 398, 399, 400 Lubricants, 295, 297 Luffa agypdaca, Vegetable Sponge Lycopodidcea;, Club-moss Family Lycopodince, Club-mosses Lycopodium, 167 Lycopodium sp., Club-moss Lycopods, Giant, 547 Macaroni, 33 Mace, 128, 134 Machinery, 257, 260, 263 Machines, 245, 259 Macrosporangium, 545 Macrospore, 545, 547 Madder P^amily, 401 : calisaya-tree, 188; coffee, 153, 154, 155 Madder Order, 401 Madder-red, 562 Magnesia in grains, 31 Magnolia, 358, 262, 406, 407; wood, 263 MagnolincecF, Magnolia Familv Magnolia Family, 358, 398, 406, 407: magnolia, 262; star anise, 143; tulip whitewood, 261 Magnolia grandiflora, Magnolia Mahoganv, 266 Maize, U, 15, 23, 24, 25, 28, 120, 122, 126, 159, 232, 235, 387, 420, 421; kernel, 114; range, 28 Malaria, 188 Male-fern, 179, 180, 394, 636, 539, 540 Male protoplasts, motile, 560 Mallet-heads, 269 Mallow Family, 369, 399, 410, 411: marshmallow, 166; sea-island cotton, 227; upland cotton, 225 Mallow Order, 376, 399, 410, 411 Malt, 156; liquors, 156; sugar, 32 Malting, 32 Maltose, 32 Malvacea, Mallow Family Malmles, Mallow Order Manihol utilissima, Bitter Cassava Manila, 224, 232; hemp, 232; paper, 232 IManila Hemp Plant, 233 Maple, 261; stem, 254; sugar, 101; wood, 263 Maple Family, 399: sugar-maple, 261 Marchanlia polymorpha, Umbrella Liverwort Marginicidally septifragal dehis- cence, 382 Mariopteris, Climbing Ferns Marjoram, 418. 419: oil of, 297; sweet, 137, 140, 383 Market baskets, 241 INDEX 595 All numbers refer to pages, heavy type indicating illustrations. Marshmallow, 163, 164, 166, 369, 410, 411 Marsh-marigold, 198, 199, 208, 328-356, 404, 405, 558 Mastery through choosing the better waj^, 468 Masts, 270 Matches, 245 Mats, 232, 235, 239 Matting, 223, 235; straw, 235 Mattress filling, 235 Meadow Rue, 339, 328-356 Mechanical causes in evolution, 453 Mechanical equivalent of heat, 116 Medicinal plants, 162, 163; plas- ters, 288; rhubarb, 170 Medicines, 162 Mediterranean food-plants, 124 Megaphyton, Tree-ferns Meliacece, Melia Family Melia Family: mahoganv, 266 Members, 323, 324, 326;'of flower- ing plant, 327 Menispermacew, Moonseed Family Mentha piperita, Peppermint; spicata, Spearmint Menthol, 178 Meristem, 487 Meristematic tissue, 487 Metabolism, 84 Metachlamydeif, Bellflower Series Metachlamydeous flowers, 386 Metallurgy, 300 Metal polishing, 542 Metroxylon loeve, Smooth Sago Palm Metroxylon Rumphii, Prickly Sago Palm Mezereum Family, 400: daphne, 206 Microbes, 494 Micro-organisms, 494 Micropyle, 346, 552, 556 Microspermw, Orchid Order Microsporangium, 645 Microspore, 646, 546 Migrations, 468 Mildews, 499 _ Milk-souring Bacterium, 493 Milkweed P'amily, 401 Milky juice, 361 Mineral fibers, 223; kingdom, 561, 562; substances, 321 Mineral matter in grains, 31 Mine timbering, 245 Mint, 418, 419 Mint Family, 383, 401, 41S, 419: peppermint, 147, 148; sage, 138; spearmint, 139; summer savory, 139; sweet marjoram, 140; thyme, 139 Miscellaneous condiments, 137; food-plants, 35; food-products, 91 Misconceptions of evolution, 439, 440 Mistletoe, 210, 211, 212 Mistletoe Family, 398: mistletoe, 210, 211 Mixed diet, 118 Mixed fibers, 225, 231 Models, 280 Modern food-plants, 124 Molasses, 101 Molded ornaments, 287 Monadelphous stamens, 366 Monkshood, 189, 191, 196, 208, 328-356, 404, 405 Monocots, 377 Monocotyledones, Monocotyl Sub- class Monocotyledonous, 388 Monocotyl Subclass, 391, 397 Monoecious, 374 Montgomerie, Dr. W., 286 Moonseed Family, 398 Moracew, Mulberry Family Mordant, 294, 295 Morning-glory Family, 379, 401, 416, 417: sweet potato, 68, 69 Morphine, 182 Morphological, botany, 10; difi"er- entiation, 322, 572; units, 323 Moss, 395, 519, 544; Iceland, 395; Irish, 105; Peat, 394 Mosses, 308 Mosswort Division, 395, 396 Mossworts, 530 Mother of vinegar, 155 Motile gametes in cycads, 554; protoplasts, 560 Motion in plants, 573 596 INDEX All numbers refer to pages, heavy type indicating illustrations Mountain, clematis, 335, 328-3r)6; laurel, 202, 379; selaginella, 545 Mouse-tail, 330, 331, 332, 328- 340, 356, 404, 405 Mucilaginous material, 485; sub- stances, 163 Mucoraceoe, Pin-mold Family Mucor Mucedo, Pin-mold Mulberry Family, 378: fig, 102; hops, 157; Indian hemj), 180, 181; India rubber-tree, 282 Musacece, Banana Family Musa sapientum, Banana; textilis, 233, Manila Hemp Plant Mwici, True Mosses Mushroom, 125; field, 107, 113, 395 Mushroom Division, 503 Mushroom Subdivision, 395, 396 Mushroom-lichen, 508, 509 Mushroom-lichen Family: mush- room-lichen, 509 Mushrooms, HI, 308, 501; poi- sonous, 213 Musical instruments, 245, 263 Muskmelon, 88, 95, 121, 124, 283 Must, 155 Mustard, 128, 133, 177; oil of, 133; volatile oil of, 173 Mustard Family, 362, 398, 406, 407: black mustard, 133; Brus- sels sprouts, 69; cauliflower, 70; common cabbage, 69; garden kale, 68; horseradish, 144; kohl- rabi, 69; radish, 55; Savoy cab- bage, 69; shepherd's purse, 556; tree-cabbage, 274; watercress, 70, 71; white mustard, 133; wild kale, 66, 67 Mustards, 362 Mutant, 458 Mutation, 458 Mutationism, 458 Mutations like special creations, 460 Mutual help, 469; support, 531 Mycelium, 497, 4)96 Mijosurus minimus, Mouse-tail Myricacece, Bayberry Family Myricales, Bayberry Order Alyrislica frograns, Nutmeg M yristicacew, Nutmeg Family Myrtncew, Myrtle Family Mtjrtales, Myrtle Order Myrtle P'amily, 400: allsi)ice, 130; Brazil-nut, 44; clove, 129 Myrtle Order, 400 Mystery of life, 567 Naked-seed class, 393, 397 Naked-seeded gynoccium, 392 Natural objects not diagrammatic, 327 Natural orders, 310, 311 Names of plants, early, 3 Napkins, paper, 224 Nasturtium Armoracia, Horse- radish officinale, Watercress Native home and culture-period, 123 Native homes of food-plants, 120, 121 Natural, classification, 308; selec- tion, 447, 460; system, 310, 311, 328, 433 Nature, 562 Nebula hypothesis, 464, 465 Neck of archegonium, 521, 528, 551 Nectar, 29, 346; in flowers, 557 Nectar-gland, 29 Nectar-leaves, 348 Ncmalion multijidum, Thread- weed Neo-Darwinism, 448, 449 Neo-Lamarckism, 445, 449 Ncrium Oleander, Oleander Nervation, 337 Net floats, 280 Nets, 223 Netted-veined, 337 Netting, 223 Nettle Family, 398 Nettle Order, 398 Neutral flower, 371 Nicoliana rusiica, Turkish To- bacco Tohacum, Virginia Tobacco Nicotine, 184 NigcUa spp.. Fennel-flowers Nightshade, black, 208 Nightshade Familv, 382, 401, 416, 417: belladonna, 187; bitter- INDEX 597 A\[ numbers refer to pages, heavy tyye imlieatiug illusi rations. s\v(M^t, 209; black nightshade, 208; egsr plant, 85; jimson-weed, 200; red pepper, 131, 132; to- baccos, 184; tomato, 83, 84; white potato, 59, 60 Nine-pins, 245 Nitrocellulose, 228 Nitrogen, 570; need of, 115 Nitrogenous food, 114 Node, 23, 317, 318 Nomenclature, 314; binomial, 4 Non-alcoholic beverages, 150 Non-motile spores, 490 Non-nitrogenous foods, 115 Non-nutrients, 31 Non-sexual, generation; 560; re- production, 480, 483, 512; spores, 511 Northern Fox-grape, 88, 93, 125 Norway Spruce, 272, 551, 552, 553 Nostoc, 522, 574 Nostoc spp., Fallen Stars Nucellus, 551, 556 Nucleus, 473 Nurse-plants, 512, 548, 560 Nursing by mosswort gameto- phyte, 531 Nut, 374; drupaceous, 376 Nutlets, 364 Nutmeg, 128, 134, 177; oil of, 130, 297 Nutmeg Family, 398 : nutmeg, 134 Nut-oils, 101, 296 Nutrients, 31 Nutrition, organs of, 321 Nuts, 35 Nux vomica, 188, 189, 190 NymphoEcece, Water-lily Family. Oak, 294, 414, 415; cork, 277, 278; Enghsh, 258; red, 257 Oaks, 374 Oak wood, 256 Oakum, 231 Oars, 259 Oats, 11, 12, 13, 14, 15, 25, 120, 124, 126, 235, 387, 420, 421; kernel, 114; range, 27 Ocrea, 372 Ocreate stipules, 372 Odors of flowers, 557 (Ecology, 10 (Eitolhera spp., Evening Primrose (Enoiheracea;, Evening Primrose Family Offensive odors caused by blue alga, 475 Offspring, of two parents, 512; well-endowed, 510 Oil finish, 296 Oil, of almond, 167; of cacao, 107; of cloves, 129, 130; of mustard, 173; of nutmeg, 130; of saffron, 175; of turpentine, 288, 296; of wintergreen, 147 Oil reservoirs, 360 Oil-cloth, 230 Oils, 222, 295; drying, 295; fixed, 34, 128; non-drying, 297; vola- tile, 128 Ointments, 288 Old age, 571 Oleacece, Olive Family Olea europea, Olive Oleander, 206, 207, 209 Oleic acid, 296 Olein, 296 Oleoresins, 287 Olive, 100, 105, 124, 167, 296; oil, 101, 167, 296, 297; wood, 269 Olive Family, 401: olive, 105; white ash, 259 Once-compound, 339 Onion, 43, 63, 64, 120, 124, 146, 390, 424, 425; bulb, 114 Ontogeny, 435, 560 Oomycetes, Vater-mold Fungi Oospore, 484 Open aestivation, 371 Ophioglossum vulgatum, Adder- tongue Opium, 182 Opium Poppy, 182, 183, 296, 361 Opposite, floral organs, 368; leaves, 342, 352 Opuntiales, Cactus Order Orange, 88, 97, 121, 124; pulp, 114; wood, 266 Orange-flower oil, 297 Orange-peel oil, 297 Orchidacea, Orchid Family Orchidales, Orchid Order Orchidece, Orchids Orchid Family, 391, 397, 424, 425: 5'dS INDEX All numbers refer to pages, heavy type indicating illustrations. showy ladies' slipper, 220; yel- low ladies' sHoper, 220; vanilla, 149 Orchid Order, 391, 397, 424, 425 Orchids, 218, 219, 311 Order, 8, 428 Orderly progress, 469 Orders, Linna^an, 309; natural, 310, 311 Ordinary English in describing, 312 Organic, compounds, 562; evolu- tion, 431, 572; materials, 570; realm, 562, 569; substances, 321 Organisms, 321, 562; as self-build- ing boats, 569 Organs, 321; adhesion of, 365; analogous, 321 Oriental food-plants, 124 Origanum Majorana, Sweet IMar- jorum Origin, of adaptations, 442; of hfe, 566; of life in the sea, 491; of species, 441 Origins, the problem of, 428 Ornamental, flowers, 303; woods, 268, 269 Ornaments, 268, 276 Orpine Family, 399 Orthotropous ovule, 372 Oryza saliva, Rice Osiers, 241 Osmunda, 537 Osmnndacece, Roval-fern Family Ovaries, inferior, 350, 365, 380; half-inferior, 350; superior, 350 Ovary, 12, 14, 319, 345, 556 Overproduction of offspring, 447 Overshoes, 283 Overstimulation, 159, 160 Ovulary cavity, 345; divided by partition, 363 Ovule, 12, 14, 319, 325, 352, 550, 551; parts of, 346 Ovules, anatropous, 346, 355; campylotropous, 363; ortho- tropous, 372 OxalidacecE, Oxalis Family Oxalis Family, 399 Oxeye, 380, 435 Oxidized hydrocarbons, 285, 287 Oxygen, 570; in grains, 31 Packing, 223, 235, 279, 280 Packing material, 239 Paionia officinalis, Peony Pails, 243; paper, 224 Painting, 222, 296 Paints, 295 Palaqidum Gutta, Taban-tree Pahnacea, Palm Family Pahnce, Palms Palmales, Palm Order Palm, oils, 296, 297, 389, 397, 422, 423; sago, 388; seeds, 282; stem, 255 Palm Family, 388, 397, 422, 423: coconut, 46, 47; date, 100, 101; rattans, 237, 238; sago palms, 109, 110; vegetable ivory, 276, 276 Palm Order, 389, 397, 422, 423 Palmatic acid, 296 Palmatin, 296, 297 Palmate nervation, 340, 352 Palmately compound, 340; di- vided, 340; ribbed, 337 Palm-leaf fans, 388 Palms, 311, 389 Paneling, 263 Paniculate inflorescence, 345, 352 Panspermia, 567 Papaveracea', Poppy Family Papaverales, Poppy Order Papaver somniferuin, Opium Poppy Paper, 223, 224, 228, 230, 235, 241; boxes, 224; canoes, 224; car- wheels, 224; making of, 222; manila, 232; napkins, 224; pails, 224 Papier-mache, 224 Papilionaceous corolla, 366 Pappus, 386 Parallel-veined leaves, 387 Paraphyses, 487, 503 Parasite, 303, 494 Parasitic fungi, 504 Parchment, vegetable, 230 Parenchyma, 530 Parietal placenta, 362 Parmeliacece, Shield-lichen Family Parsley, 137, 140, 370, 410, 411 Parsley Family, 370, 400, 412, 413 anise, 142; asafetida plant, 175 caraway, 142; carrot, 55, 56, 57 INDEX 599 All numbers refer to pages, heavy type iiulicating illustrations. celery, 75; coriander, 143, 144; parsley, 140; jjarsnip, 57; poison hemlock, 194, 195; water hem- lock, 193 Parsley Order, 371, 400, 412, 413 Parsnip, 43, 57, 120, 124, 219, 370, 412, 413; root, 114 Partition in ovary, 363 Parts of a seed-plant, 316 Pasque-flower, 338, 341, 328-356 Pasteboard, 235 Pastinaca saliva, Parsnip Pasture plants, 303 Patterns, 270 Pea, 40, 48, 120, 124, 365, 408, 409 Peace and progress, 468 Peach, 88, 89, 121, 124, 364 Peanut, 35, 45, 120, 124, 365, 410, 411; kernel, 114; oil, 100, 296, 297 Pear, 87, 88, 121, 124, 363 Peat, 298; ash, 300; bogs, 298; moss, 239, 242, 298, 394, 522, 523, 524, 525 Peat-moss Family : peat-moss, 242, 523-525 Pecan, 35, 40, 376; nut, 120, 125 Pecopteris, 535 Pecopteris, Tree-ferns Pedate, 340 Pedicel, 344 Peduncle, 343 Pentadelphous stamens, 368 Peony, 329, 328-356, 404, 405 Pepo, 384 Pepper, black, 128, 131; red, 128, 131, 132, 382, 416, 417 Pepper Family, 398 : black pepper, 131 Peppermint, 146, 147, 148, 177, 383; camphor, 178; oil, 297 Pepper Order, 398 Perennial, 58, 331, 332; herbs, 352 Perfect flowers, 13, 347, 354 Perforated cells, 524 Perfumery, 295, 297 Perianth, 43, 319; glumaceous, 390; petaloid, 390 Pericarp, 351, 352, dehiscing dor- sally, 359; dry, 355; fleshy, 355; winged, 359 Permanent tissue, 487 Perigynous floral organs, 350, 355 Peristome, 527, 529 Persistence, 466, 468 Petal, 42, 319, 348, 352 Petaloid perianth, 390; sepals, 348 Petiole, 336, 537 Petiolule, 339 Petroselinum hortensc, Parsley Phanerogamia, Phenogams PhoEnogamia, Phenogams Phaiophycea, Brown Alga; Phaseolus lunafus, Lima Bean vulgaris, Kidney Bean Phenogamia, Phenogams Phenogams, 309, 393, 396, 397 Phenogams and cryptogams, 550 Philopena almonds, 365 Phlox Order, 383, 401, 418, 419 Phanix dactylifera. Date Phosphorus in grains, 31 Photographer's trays, 284 Photosynthesis, 85 Phycoeyanin, 471 Phycoerythrin, 487 Phycophaein, 485 Phylogeny, 435, 560 Physical basis of life, 471 Physiological botany, 10; division of labor. 319, 321, 572 Phytelephas microcarpa, Vegetable Ivory Phytolacca decandra, Pokeweed Pianos, 245, 263 Picea excelsa, Norway spruce Pictures, botanical, 312 Pie-plant, 91 Pigments, 290, 291 Pigmy Buttercup, 444 Piling, 245, 257 Pimento officinalis. Allspice Pimento walks, 130 Pimpenella Anisum, Anise Pina, 234 Pinacea, Pine Family Pine, 241, 253, 392, 424, 425; Scotch, 269; wood, 250, 251, 270 Pine Family, 392, 397, 426, 427, 554: European larch, 271; hem- lock, 273; juniper, 158; Norway spruce, 272; red cedar, 273; red- wood, 273; Scotch pine, 269 600 INDEX All numbers refer to pages, heavy type indicating illustrations. Pine grove illustrating mutual ac commodation, 453, 454 Pine Order, 393, 397, 426, 427 Pines, 550 Pineapple, S8, 103, 121, 124, 233; fiber, 232; gall, 272 Pineapple-cloth, 234 Pineapple Family, 397: pineapple, 103; southern moss, 234 Pin-mold, 495, 496, 497 Pin-mold Family: pin-mold, 496, 497 Pin-mold Fungi, 495 Pink Family, 398 Pinnate, 341; nervation, 352 Pinnately, compound, 341; nerved, 341 Pinus sylveslris, Scotch Pine Piperacece, Pepper P^amily Piperales, Pepper Order Piper nigrum, Black Pepper Piping, 287 Pistil, 11, 14, 308, 319, 345; com- pound, 347; simple, 347 Pistillate flowers, 347 Pistil, parts of, ovary, 345; ovule, 346; placenta, 346; stigma, 345; style, 345 Pii^um sativum, Pea Pith, 250, 254 Pith-rays, 250, 253, 254 Pivotal place of plants in economy of nature, 574 Placenta, 346; axile, 355; dorsal, 346; parietal, 362; ventral, 346 Plaiting, 223, 235 Planetesimal hvpothesis, 465 Plane-tree, 267, 268 Plane-tree Famil}', 399: American sycamore, 267 Planks, 270 Planlaqinacece, Plantain Family PIrnifaginnles, Plantain Order Plantain Family, 401 Plantain Order, 401 Plant, formulas, 352; groups, 358; names, early, 3 I^lant life and human life, 575 Plants, annual, 11; biennial, 52; compass, 73; did'cious, 360; habit of, 359; mona'cious, 374; ocreate, 372; perennial, 58; polygamous, 347; shrub, 36; tree, 36; glabrous, 343; pubes- cent, 343 Plants and animals defined, 573, 574 Plants, how named, 2; in general, 574; our dependence upon, 1; needs of, 2 Plant's place in Nature, 561 Plants poisonous, to eat, 192; to handle, 217 Plant segment, 324 Platanacece, Plane-tree Family Plalanus occidentalis, Ameiican Sycamore Pleurococcacece, Wall-stain Algae Pleuroccus vulgaris, Wall-stain Alga Plicate aestivation, 381 Plicate-convolute aestivation, 381 Plum, 88, 90, 121, 124, 364; wood, 357, 263 Plumule, 48, 317, 318, 319, 546, 556 Podded Jute, 232 Poison, Dogwood, see Poison- sumac; Hemlock, 194, 195, 209, 370, 410, 411 Poison-ivy, 217, 218, 219 Poison-oak, see Poison-ivy Poisonous bark, 196; drugs, 176; flowers, 205, 208; fruits and seeds, 209; herbage, 199; honey, 205, 207, 208; mushrooms, 111, 213; juice, 357; plants, 112, 162, 163, 192, 219; substances, 302; underground parts, 192; volatile oils, 177 Poisons, 162; as by-products, 192 Poison-sumac, 217, 220 Poke, Indian, 390, 424, 425 Pokeweetl, 195, 196, 208, 209 Pokeweed Family, 398: pokeweed, 195, 196 Polemoniales, Phlox Order Poles, 245, 270 Pollen, 12, 14, 319; grain, 550, 551, 556 Pollen-sacs, 325, 326 Pollen-tube, 551, 555, 556 Pollination, 557 Polygamous flowei-s, 347, 354 INDEX GOl All numbers refer to pages, heavy type indicating illustrations. Polufjonacecv, Buckwheat Family Polygonales, Buckwheat Order Polt/goniun Convolvulus, Climbing Buckwheat Poll/ pod iaccfc, Polypody P^amily Polypody Family: male-fern, 179; pteris,'537 Polijporncece, P o r e-m u s h r o o m Family Pome, 365 Pond-scum, 478, 479, 480, 499, 558 Pond-scum Family: pond-scum, 479, 480 Poplar, 241, 263, 264, 377, 414, 415; wood, 263 Poppy, 208, 406, 407 Poppy Family, 361, 398, 406, 407: opium poppy, 182, 183 Popp)'-oil, 296 Poppv, Opium, sec Opium Poppy Poppy Order, 363, 39S, 408, 409 " Populus treuiuloides, Poplar Porcupine-wood, 272 Pore-mushroom Family: amadou, 241 Pores of wood, 252, 538 Poricidal dehiscence. 362; of an- thers, 379 Portable boats, 284 Portulacaca, Portulaca Family Posts, 258, 270 Potash in grains, 31 Potassium, 74 Potato berries, poisonous, 210 Potato, sweet, 43, 58. 59, 379, 416, 417; white, 43, 59, 60, 210, 382, 416, 417 Potentialities of protoplasm, 572 Pot-herb Jute, 232 Pot-herbs, 55 Powdery mildew, 499, 500 Powdery-mildew Family: powdery mildew, 500 Preference, power of, 569 Prehistoric food-plants, 124 Prickly Sago Palm, 109, 110 Primary leaves, 318, 319; tissue, 542 Primitive centers of agriculture, 122, 123 Primitive man, 302 Primitive versus degenerate forms, 549 Primrose Family, 401 Primrose Order, 401 Prit)iulnc('n\ Primrose Family Priuiiildle!^, Primrose Order Princes of the Vegetable Kingdom, 389 Prindpes, Palm Order Printing-ink, 294, 295 Printing-paper, 224 Progress and peace, 468; in evolu- tion, 466; made in spite of com- petition, 468 Progressive fixity of growing struc- tures, 571 Prolific multiplication, 512 Prosenchyma, 530 Protection, organs of, 321, 538 Proteid, 33, 74, 114, 115, 471 Protein in foods, 114 (sec also Pro- teid) Prothallial cells, 556 Prothallus, 533, 536, 551 Prothallu.s-cell, 546 Protonema, 523, 526 Protoplasm, 471; artificial, 562; fundamental properties of, 571; potentialities of, 572 Protoplast, 473 Protoplasts, artificial, 564; fusion of, 560 Pi'imus Amijgdaliis, Almond Cerasus, Sour Cherry domestica, Plum Persica, Peach serotina, Wild Black Cherry Prussic acid in cherry leaves, 204; in cherry stones, 205 Pseudo-fibers, 225, 239 Pseudopodium, 525 Pseudo-root, 481, 521, 536 Pseudo-shoot, 481 Pseudo-woods, 256, 272 Plcridophijta, Pteridophyte Divi- sion Pteridophyte Division, 548 Pteridophytes, 394, 396 Pteris, 537 Pubes(;ent, 343 Pul.se, 35, 40 Pulse Family, 365, 398, 399, 410, 602 INDEX All numbers refer to pages, heavy type indicating illustrations. 411: courbaril-tree, 289; dyer's indipo-.shrub, 293; gum arable tree, 164; kidney bean, 49, 50 Lima bean, 51; locust, 197 logwood-tree, 294; pea, 48 peanut, 45; tragacanth shrub, 165; Zanzibar copal-tree, 289 Pumpkin, 76, 77, 78, 85, 114, 121, 124, 383 Purifiers of air and water, 304 Pussies, 373 Putrefaction, 493 Pyrenoid, 476 Pyrography, 263 Pyrus communis, Pear Mains, Apple Quarter-sawed timber, 250, 257, 268 Quercus pedunculala, English Oak rubra, Red Oak Suber, Cork Oak Quince, 88, 121, 124, 363, 408, 409; seed, 163, 164 Quinine, 182, 186 Raceme, 344, 345 Racemose inflorescence, 345, 352 Rachis of inflorescence, 14, 344 Radicle, 48, 317, 318, 319, 557 Radish, 43, 55, 120, 124, 146, 362, 406, 407 Railway ties, 257, 258, 270 Rain-guard, 16 Ranales, Cro^-foot Order Rancid oil, 296 Ranunculaceo', Crowfoot Family Ranunculacea?, family tree, 437 Ranunculnles, Crowfoot Order Ranunculus acris, Tall Buttercup aquadlis. White Water Crow- foot Cymbalaria, Seaside Crowfoot pygmceus, Pigmy Buttercup sceleralus. Ditch Crowfoot Rape, 362 Rape-oil, 297 Raphanus saiivus. Radish Raphe, 346 Rapid multiplication of cells, 511 Raspberry, 88, 91, 121, 125, 364, 408, 409 Rations, 115, 117 Rattan, 232, 235, 237, 238, 388, 422, 423 Raw products, 302 Ray-floret, 380 Reappearance of life, 566 Recapitulation, law of, 435, 560 Recapitulation or phylogeny by ontogeny, 559 Recent food-plants, 125 Receptacle, 61, 349, 385 Recreational appliances, 245 Red, alga;, 487; cedar, 273, 392; cedar oil, 297; cedar wood, 270; oak, 257; pepper, 128, 131, 132, 136, 382, 416, 417 Redwood, 270, 273, 392, 426, 427 Reed, 235 Refuse in foods, 114 Regular flowers, 349, 359 Reproduction, 572; by budding, 495; by fission, 476; organs of, 321; sexual, 480; vegetative, 510 Reproductive system, 322, 343 Reservoirs of volatile oil, 359 Resin, 288 Resin-ducts, 252, 253 Resinous electricitv, 288 Resins, 177, 178, 222, 285, 287 Resting spores, 475, 568 Resupinate flower, 391 Retting flax, 230 Reversion, 436 Rhamnacece, Buckthorn Family Rhamnalcs, Buckthorn Order Rheum officinale. Medicinal Rhu- barb Rhaponiicum, Garden Rhubarb Rhizome, 336, 539 Rhodophycew, Red Alga Rhoedales, Poppy Order Rhubarb, 125, 412, 413, 372; gar- den, 91, 104, 121; medicinal, 166, 170 Rhus Toxicodendron, Poison-ivy Vernix, Poison-sumac Ribes rubrum, Common Currant Ribs, 337 Riccia spp., Crystalworts Ricciacew, Crvstalworts Rice, 11, 15, 16, 17, 25, 120, 122, INDEX 603 All numbers refer to pages, heavy type indicating illustrations. 124, 126, 23o, 387, 420, 421; kernel, 114; range, 28 Ricinus coniiininis, Castor-oil Plant Rigging, 235 Rind, 485, 540 Road materials, 244 Rohinia Pseudacacia, Locust Rock-rose Family, 400 Rod-germ Family: hay bacillus, 492; milk-souring bacterium, 493; vinegar ferment, 166 Root, 323, 324, 533, 638 Root-cap, 537, 638 Root-hairs, 317, 318, 319 Root-member, 326, 327 Roots, brace, 23 Rootstock, 336 Root-tuber, 43 Ropes, 223, 230 Rosa alpina, Alpine Rose gallica, French Rose spinosissima, Scotch Rose Rosacea, Rose Family Rosales, Rose Order Rose, 146, 408, 409, 432, 435; al- pine, 378; French, 150; Scotch, 161 Rose Family, 363, 399, 408, 409: almond, 42; alpine "rose, 378; apple, 86. 87; peach, 89; pear, 87; plum, 90; quince, 88; rasp- berry, 91; roses, 150, 151; sour cherry, 90; strawberry, 92; wild black cherry, 260 Rose Order, 367, 399, 410, 411 Roses, 364; an "unpruned" group, 440 Rosette, 342 Rosin, 288, 294 Royal-fern Family: osmunda, 537 Rubber, 280; balls, 284, crude, 283 Rubber-tree, Brazilian, 281; India, 282 Rubber tubing, 284; type, 284 Rubbery materials, 287 Rubiacece, Madder Family Rubiales, Madder Order Rub us idceus, European Rasp- berry strigosus, Wild Red Raspberry Rudimentary flowers, 13, 14; or- gans, 436; ovules, 352 Rue Family, 399: lemon, 97; orange, 97 Rue, Meadow, 339, 328-356 Rules for telling a toadstool, 214 Rum, 159 Runners, 92 Rush, 232, 234, 235, 390, 422, 423 Rush Family, 390, 397, 422, 423: rush, 234 Russia leather, 297 Rustic work, 279 Rutacew, Rue Family Rye, 11, 15, 18, 25, 27, 114, 120, 124, 126, 159, 235, 387, 420, 421 Saccharomyces cerevisia-, Yeast Saccharomycetacece, Yeast Family Saccharomycetes, Yeast Fungi Saccharum officinarum, Sugar-cane Sac-leaves, 550 Sac-member, 326, 327 Saddles, 244 Saffron, 170, 175, 176, 390, 424, 425 Saffron Crocus, 175, 176 Sage, 137, 138, 170, 383, 418, 419 Sago, 104, 125, 422, 423 "Sago-palm," .555 Sago palm, prickly, 109, 110; smooth, 109; spineless, 104 Sago-palms, 121, 388 Sail-cloth, 230, 232 Sails, 223 Salads, 55 Salicacea;, Willow Family Salicales, Willow Order Salix sp., Willow Salvia officinalis, Sage Samara, 358 Sambucus canadensis, Elder Sandalwood Order, 398 Sand-binders, 303 Santalales, Sandalwood Order Sapindales, Soap-berry Order Sapodilla Family, 401: taban-tree, 286 Sapotacece, Sapodilla Family Saprolegniaceie, Water-mold Fam- iiy Saprolegnia Thnrcli, Water- mold 604 INDEX All numbers refer to pages, heavy typo imlicating illustrations. Saprophyte, 493 Sap-wood, 240 Sassafras, Kio, 168. 360, 406, 407; oil of, 297; pith, 163; wood, 260 Sassafras officinale. Sassafras Haturein hortensis, Summer Savory Savory, 418, 419; herbs, 128, 137; seeds, 128, 137; summer, 137, 383 Savoy cabbage, 69 Saxifragacetr, Saxifrage Family Saxifrage Familv, 399: currant, 94 Scale-like outgrowths, 538 Scale-tree, 299, 301 Scale-tree Family: scale-tree, 299, 301 Scallop Squash, 80 Schizocarp, 370 Schizomycetes, Fission Fungi Scitaminales, Banana Order Sclerenchyma, 538, 540 Sclerotic tissues, 538 Scotch Pine, 269; rose, 151 Scouring-rush, 541, 542, 543; giant, 299 Scouring-rush Family: scouring- rush, 541, 543 Screens, 223 Scrophulariacece, Figwort Family Scutellum, 388 Sea Island Cotton, 225, 226, 227 Sealing-wax, 288 Seaside Buttercup, evolution of, 462 Seaside Crowfoot, 463 Sea-t angle Familv: sea-tangles, 486, 488 Sea-tangle.s, 485, 486, 488 Seaweed Division, 491 Seaweed Subdivision, 395, 396 Seaweeds, 308 Secale cereale, Rye Secondary, inflorescence, 352; leaves, 318, 319; tissue, 542 Sedge Family, 397 Seed, 350, 351, 550; albuminous, 355; exalbuminous, 363, 557; of flax, 317, 318 Seed-bud, 48, 317, 318 Seed-coat, 316. 317, 318 Seed-food, 29, 316, 317, 318 Seed-leaves, 46, 48, 317, 318 Seedling, development, 317; of flax, 318, 319 Seed-oils, 101 Seed-plant Division, 393, 396, 397 Seed-plants, 393, 396, 397 Seed-root, 48, 317, 318 Seeds, 352; make best provision for off.spring. 550; parts of, 29, 49, 316, 352; the greatest achievement of the vegetable kingdom, 560 Seed-stem, 317, 318 Seed-wing, 551 Seed wort Division, 394, 396 Seedworts, 393, 394, 396, 397 Selaginella, 550 SelagineUacece, Selaginella Family Selaginella Family: selaginellas, 545-547 Sdagindla spp., Selaginellas Selaginellas, 545-547 Selected adaptations, 446, 452 Selection, artificial, 127, 446, 447; natural, 447, 448; subordinate role of, 460 Self-control inherent in every or- ganism, 464 Self-movement, 461 Sepal, 29, 319, 352 Septicidal dehiscence of capsule, 379 Septic organisms, 177 Sequoia sempemrens, Redwood Service versus competition, 468 Sessile, 342 Sewing-thread, 223 Sexual, generation, 560; reproduc- tion, 480 Sexuality lost in certain fungi, 501 Shade trees, 303 Shagbark Hickorv, 41 Sheath, 337 Sheath-algaj, 482, 483, 484, 514, 558; compared with spore-sac fungi, 501 Sheath-alga Family: cushion sheath-alga, 484; free-branching sheath-alga, 483 Sheep Laurel, 202, 379 Shelf fungus, 239 Shell substitute, 284 INDEX 005 All numbers refer to pages, heavy type indicating illustrations. Shepherd's Purse, 556 Shield-lichen Family: Iceland moss, 169 Shingles, 270 Shipbuilding, 256, 270 Ships, 259 Ships' knees, 270 Shoe-lasts, 263 Shoemaker's wax, 288 Shoe-pegs, 245, 263 Shoe-soles, 287 Shoes, 282; wooden, 263 Shoot, 323 Shoot-segment, 323 Shoots, kinds of: runners, 92; spur, 271 Showbill type, 263 Showy Ladies' Slipper, 220 Shrub, 36, 306, 333 Siamese Gamboge-tree, 290, 291 Sigillaria, 547 Sigillaria, Giant Club-mosses Silica in epidermis, 542; in grains, 31 Silique, 363 Silk, artificial, 224, 228; of maize, 24 Silk-cotton Family: cocoa, 107, 108; Sterculia Family, 399 Silkworm food, 303 Simple inflorescence, 352; leaves, 339, 342; pistil, 347 Sinapis alba, White Mustard Sinker, 211 Size of plants, enormous, 575 Skiffs, 260 Slippery Elm, 165 Smokeless fuel, 300, 301; powder, 224 Smooth Sago Palm, 109 Snow-on-the-mountain, 203, 207, 217 Snuff, 185 Soap, yellow, 288 Soap-berry Order, 399 Soaps, 288, 295, 296 Socrates, poisoning of, 194 Soda in grains, 31 Soda water mixtures, 150 Soft pine, 270; soap, 296 Soil bacteria, 494 Soil-binders, 303 Soil-building by lichens, 506 Soil-makers, 304 iSolnnacav, Nightshade Family Solarium Dulcamara, Bitter- sweet Lycopersicum, Tomato Melongena, Egg Plant nigrum, Black Nightshade luhcro.su m, White Potato Solar system, 464 Soldering flux, 288 Soles, 280 Solid bulb, 336 Solitary flowers, 345, 352 Solvents, 296 Soredium, 506, 508 Sorghums, 236 Sorus, 179 Sounding-boards, 270 Sour Cherry, 90 Southern Moss, 232, 234 Souvenirs, 268 Spadix, 388 Spars, 243, 270 Spathe, 388 Spathifloro', Arum Order Speaking tubes, 287 Spearmint, 137, 139, 170, 177, 338; oil, 297 Special creation, 429 Species, 4, 428; as units of, classi- fication, 431 ; destruction of 432; fixity of, 429, 430; limits of, 431; origin of, 441 Spermagone, 505 Spermatophyta, 8 Spermatophyla, Seed-plant Divi- sion Spermatophvtes, 393, 394, 396, 397 Spermatozoid, 515, 517, 527 Sphagnnceo', Peat-moss Family Sphagnum spp. Peat Moss Sphenophyllum ctineifolium. Wedge-leaf Sphenopteris, Climbing-ferns Spicate inflorescence, 373 Spices, 128. 302; danger of, 130, 133; hi.story of, 137 Spiderwort Family, 397 Spike, 373 Spikclet, 13 606 INDEX All numbers refer to pages, heavy type indicating illustrations. Spinach, 55, 71, 72, 120, 124; leaves, 114 Spinacia oleracea, Spinach Spindles, 245 Spineless Sago-palm, 104 Spinning, 222 Spirits of turpentine, 288, 296 Spirituous liquors, 159 Spirogyra sp., Pond-scum Spitting, danger from, 494 Splint, 241 Splints, surgical, 245 Sponge Cucumber, 238, 383, 418, 419 Spontaneous generation, 5G5; va- riations, 449 Spools, 245, 263 Sporangium, 484, 541 Spore, 167 Spore-base, Fungi, 501; Lichens, 508 Spore-case, 529 Spore-layer, 529 Spores, 511 Spore-sac Fungi, 499, 504 Spore-sac-leaf, 534 Spore-sac Lichens, 504 Spore-sacs, 550 Sporophyll, 541 Sporophyte, 485, 514, 515 Spring wood, 251, 253 Spruce, 241, 292, 294, 424, 425, 551, 552, 553; aphis, 272; Nor- way, 272; wood, 270 Spunk, 239 Spur, 271 Spurge Family, 399: bitter cas- sava, 110, 111; Brazilian rubber- tree, 281; caper spurge, 216; castor-oilplant, 172, 173; snow- on-the-mountain, 203 Sputum, danger from, 494 Squash, 85, 121, 124, 383, 418, 419; hubbard, 81; long white, 79; scallop, 80; summer crook- neck, 79 Staff, 232 Stamens, 12, 14, 309, 319, 352, 550; diadelphous, 366; mona- delphous, 366; pentadelphous, 368; syngenesious, 384 Staminate flowers, 347 Staminodes, 340, 341, 348, 352 Standard, 48, 366 Star Anise, 137, 143, 358, 406, 407 Starch, 31; conversion into sugar, 32 Staves, 259 Stem, 324, 538; of fern, 540 Stem-member, 326, 327 Stem-part, 323, 325 Stems, 387, 533 Stem-tip, 320, 556 Stem-tuber, 43 Sterculiacea:, Silk-cotton Family Sterculia Family, 399 Stiffening, 223, 232 Stigma, 12, 14, 319, 345, 555, 556; enlargement of, 557 Stimulants, 156, 160, 161 Stimulating beverages, 161 Stimulation, 159 Stimuli, response to, 562 Stipulate leaf, 358, 359 Stipule, 358, 359 Stipules, ocreate, 372 Stirrups, 244 Stomata, 529, 530 Stone-fruit, 364 Stone of drupes, 365 Stoppers, 280 Storage of food-materials, 485, 538 Strap-shaped corolla, 379, 380, 381, 385 Straw, 232, 235; hats, 223; mat- ting, 235 Strawberry, SS, 92, 121, 125, 364, 408, 409 Strawberrj'-shrub Family, 398 String-beans, 85 Structure, 572 Struggle for existence, 447, 454 Struggles for supremacy often desfroj' what is best, 468 Strychnine, 182, 188 Strychnos Nux-vomica, Nux Vom- ica Stuffing for saddles, 238 Sturtevant, Dr. E. L., 456 Style, 12, 14, 319, 345 Suberin, 279 Subtend, 342 Succulent parts for dissemination, 560 INDEX G07 All numbers refer to pages, heavy type indicating illustrations. Sudden adaptations, 457, 459; variations, 450 Sugar, 32, 101 Sugar-beet, 101 Sugar-cane, 101, 106, 121, 124, 387, 420, 421; stalks, 298 Sugar-maple, 101, 261, 263 Sugars, 562 Sulphur in grains, 31 Sumac Family: poison-ivy, 218; poison-sumac, 220 Summer, crook-neck squash, 79; savory, 137, 139, 383; wood, 251, 553 Sunflower, 420, 421 Sunflower Family, 385, 401, 420, 421: dandelion, 443; Jerusalem artichoke, 61, 62; lettuce, 72, 73, 74; oxeye, 380; woimwood, 160 Superior ovary, 350 Support, organs of, 321 Surface fibers, 224, 225 Surgeon's plaster, 284 Surgical appliances, 245, 284, 287; instruments, 284 Survival of the fittest, 447, 448 Suspensor, 497, 546, 547, 552, 556, 557 Suture, 351 Swamp-drainers, 303 Swarm-spore, 482, 511 Swarm-spore alga;, evolution of, 558 Sweating of cocoa, 103 Sweet, corn, sugar in, 32; flag, 170, 174, 389, 422, 423; marjoram, 137, 140, 383; potato, 43, 58, 59, 120, 124, 379, 416, 417; potato root, 114 Swietenia Mahogoni, Mahogany Sword hilts, 286 Sycamore, American, 267, 268; wood, 268 Symbiont, 508 Symbiosis, 508 Syngenesious anthers, 384 Synopsis of Seedworts, 397 Syringodendron, Giant Club- mosses System, Linnaean, 308; natural, 310, 311, 328 Systematic, botany, 9, 304, 305, 314, 315; classification, 305 Systems, artificial, 307 Taban-tree, 285, 286 Table mats, 239 Tall Buttercup or Crowfoot, 216, 241, 328-356 Tan-bark, 290, 294 Tanks, 243 Tanning, 222. 295 Tannins, 154,' 166, 222, 294 Tape, 223 Tape-worms, 180 Tapioca, 104 Taraxicuin officinale, Dandelion Taxaceip, Yew Family Taxiis baccata, Yew Tea, 150, 152; aroma, 154 Tea Familv, 400: tea, 152 Tea-tasters, 154 Technical, description, 312; terms, 312 Tegumentary system, 539 Telegraph-poles, 270 Telephones, 284 Temperatures required by life, 466 Terminal flower, 343 Terminology, 314; Linnaean, re- form in, 313 Terms, technical, 312 Ternate nervation, 352 Tennis-rackets, 245 Test of life, 568, 569 Thalidrum flavum, Meadow Rue Thallnphyla, Thallophyte Division Thallophyte Division, 509 Thallophvtes, 395, 396 Thallus, 481 Thatch, 223, 235 Theacea;, Tea Family Thea Sinensis, Tea Theine, 150 Theobroma Cocoa, Cocoa Theobromine, 150, 154, 181 Third organic kingdom, 573 Thread, 223 Thread-weed, 488, 490 Thread-weed Family: thread- weed, 490 Thyme, 137, 139, 177, 383, 418, 419; oil of, 297 608 INDEX All numlxM-s refer to pages, heavy tyi)e irxlicating illustrations. Thymeloecew, Mezereuiu Family Thymus vidgurin, Thyme Tilia idmifolia,' Elm-leaved Lin- den Tiliacecp, Linden Family Tillandsia usneoidea, Southern Moss Timber, 257; pins, 260 Tinning, 157 Tint-ball Alga, 471, 558 Tint-ball Family: tint-ball alga, 471 Tires, 284 Tissue, 486, 560; systems, 539, 560 Tissues, meristematic, 487; per- manent, 487 Toadstools, HI, 213 Tobacco, 182, 184, 208, 382, 416, 417; Indian, 201, 384, 418, 419 Toilet soaps, 296 Tomato, 83, 84, 85, 121, 124, 382; fruit, 114 Tool-handles, 259, 260, 269 Toothpicks, 245, 268 Torches, 282 Torus, 349, 350, 352; concave, 355; convex, 355; epigynous, 365; fleshy, 364; hollow, 380 Toys, 245, 259, 263, 270, 284 Trachylohiuin Hornemannianum , Zanzibar Copal-tree Tragacanth, 163 Tragacanth Shrub, 164, 165, 366, 410, 411 Tragacanthin, 164 Traveling gametes, 512 Tree, 36; of life, 434 Tree-cabbage, 274 Tree-ferns, 299, 535, 538, 540 Treenails, 259 Trees, 306, 333 Trestlework, 245 Trianon botanic gartlen, 311 Triticum sativum, Wheat True, gums, 287; mosses, 519, 530; woods. 256 Trunk of fern, 540 Trunks, 263 Truth, supreme test of, 429 Ttiuqn canndensis. Hemlock Tuberculosis bacterium, 494 Tuber, 43, 541, 542 Tubiflone, Phlox Order Tubs, 243 Tubular floret, 380 Tulip-tree, 261, 358, 406, 407 Tulip Whitewood, 261, 263 Turban Squash, 81 Turkish Tobacco, 184 Turnery, 242, 257, 259, 263, 268, 269, 277, 280 Turnip, 43, 54, 120, 124, 362; root, 114 Turpentine, 287, 288, 296 Turps, 296 Twice-compound, 339 Twine, 223, 230 Type, plants, 316; rubber, 284; wooden, 263 Ulmacece, Elm Famil}' Ulmus americana, American Elm campedris, English Elm Ulodendron, Giant Club-mosses Ulothrix zonata. Wool-weed Ulotrichacecr, Wool-weed Family Umbel, 370 Umbellales, Parsley Order Umhellijeris, Parsley Family Umbelliflorcr, Parsley Order L'mbellule, 370 Umbrella handles, 245, 274, 276 Umbrella liverwort, 515, 516, 517 518, 519, 520, 521 Uncoiled embryo, 355 Universality of life, 569 Upholsterv stuffing, 235 Upland Cotton, 225, 226 Upright posture of land-plants. 530 Urticacea, Nettle Familj- Urticales, Nettle Order Useful bacteria, 494; plants, 302 Useless organs, 436 Usnea barbata, Beard-lichen Usneacece, Beard-lichen Family Valvate aestivation, 349, 354 Vanilla, 146, 149, 391, 424, 425 Vanilla planifolia, Vanilla Vanilhn, 146 Variation, 448, 449; under domes- tication, 456 Varieties, 5, 428; cultivated, 6; do- INDEX ()()9 All numbers refer to pages, heavy tyi)e indicating illustrations. mesticated, 430; multiplication of, 12(i; origin of, 126 Various plant groups, 358 Varnishes, 288, 290, 294, 296 Vascular cryptogams, 396; parts, 538; plants, 396; system, 539 Vegeiahilia, Vegetable Kingdom Vegetable, ecology, 10; fibers, 223 foods, 113; ivory, 275, 276 388, 422, 423; morphology, 10 parchment, 230; physiology, 10 sponge, 232, 238, 240; versus animal foods, 119; wool, 228 Vegetable Kingdom, 8, 394, 396, 561, 562; culminating in seed- plants, 560; evolution of, 466 Vegetative, cone, 323; organs of crowfoot family, 330; repro- duction, 510, 560; system, 322 Vegeto-animal organisms, 573 Vehicles, 244; for pigments, 295 Veins, 337 Veinlets, 337 VenatioUj 337 Ventral placenta, 346; suture, 351 Veratrum vivide, Indian Poke Verhenacece, Verbena Family Verbena Family, 401 Vernation, 349; crozier-like, 537 Vertical hypha, 496, 497 Verticil, 342 Vessels, 243, 538, 540; in wood, 252 Vestiges, 436 Vestigial characters, 452 Vine, 333 Vine-bower Clematis, 336, 328-356 Vinegar ferment, 155 Violacece, Violet Family Violales, Violet Order Violet Family, 400 Violet Order, 400 Violins, 245, 270 Virgin cork, 278, 279 Virginia Tobacco, 184 Viscum album, Mistletoe VitacecB, Grape Family Vital processes, imitations of, 563, 564 Vitis spp., Grapes Volatile oil reservoirs, 359, 360 Volatile oils, 128, 159, 160, 170, 177, 295, 296, 297; jxjisonous, 177 Volition in plants and animals, 464 Vries, Hugo de, 457 Vulcanization, 284 Wagons, 256, 259, 260, 263 Wallace, Alfred Russel, 446 Walnut, 35, 39, 120, 124, 376, 414, 415; black, 260; English, 296; kernel, 114; white, 261; wood, 256, 260 Walnut Family, 376, 398: black walnut, 260; butternut, 40; hickory, 41; pecan, 40; walnut, 39 Walnut Order, 376, 398, 414, 415 Wall-stain Alga, 476, 477, 504 Wall-stain Family: wall-stain alga, 477 Waste products, 573 Water, Hemlock, 193, 370, 412, 413; in foods, 114; in grains, 30 Water-bottles, 284 Water-craft, 243 Watercress, 55, 70, 71, 362, 406, 407 Water-lily Family, 398 Watermelon, 88, 96, 121, 124, 383, 418, 419; pulp, 114 Water-mold, 498 Water-mold Family: water-mold, 498 Water-mold Fungi, 499 Waterproof, coverings, 284; gar- ments, 283, 284; material, 287 Water-supply, effect of forests on, 304 Water-vessels, 282 Wax, 303 Wax-beans, 85 Weapons, 245 Weaving, 222, 223 Webbing, 223, 230 Wedge-leaf, 299 Weeds, 303 Wearing apparel, 223 Well-endowed offspring, 510 Wet cooperage, 243, 257 WTieat, 11, 15, 19, 20, 28, 120, 122, 12-1. 126, 159, 235, 387, GIO INDEX All numbers refer to pages, heavy type indicating illustrations. 420, 421; gum, 31; kernel, 114; range, 26; straw, 298 Whisk brushes, 235 Whisks, 223 Whisky, 159 White, ash, 259; birch, 265; birch oil, 297; cooperage, 243, 270; mustard, 133; oak wood, 256; pine, 241, 270; pine wood, 250, 251; potato, 43, 59, 60, 120, 124, 210, 382, 416, 417; potato tuber, 114; walnut, 261; water crowfoot, 467 White wood, 263; Tulip, 261 Whorl, 342 Whorled leaves, 342 Wicks, 228; wickerwork, 223, 235, 241 Wild, black cherry, 203, 260, 263; carrot, 430; cotton, 227; kale, 66, 67; lettuce, 73; red rasp- berry, 91 Will, 568; in plants, 462 Willow, 241. 243, 244, 294, 377, 414, 475 Willow Family, 377, .398, 414, 415: poplar, 264; willow, 243, 244 Willow Order, 377, 398, 416, 417 Wind-balls, 283 Wind-breaks, 303 Wind-carried pollen, 557 Wind-flower, 328-356 Wind-pollination, 557 Wine, 156, 1.57, 243, 495 Winged pericarp, 359 Wings, 48, 366 Winter Crook-neck Squash, 81, 82 Wintergreen, 146, 148, 177, 203, 297, 378, 379, 416, 417; oil of, 562 Witch-hazel, 166, 171 Witch-hazel Family: witch-hazel, 171 Wood, 241, 298; ash, 298; origin, 254; pulj), 241; structure, 249 Wood-alcohol, 300 Wood-anemony, 205, 209, 328- 356 Wood-anemony, American (see American W ood-anemony) Wooden shoes, 263 Woodenware, 263 Woods, 222; true, 256 Wood-working trades, 242 Woody, fibers, 225, 240, 538; plants, 333, 352 Wool, vegetable, 228 Wool-weed, 480, 481, 558 Wool-weed Family: wool-weed, 481 World-making an evolution, 464 Wormwood, 159, 160, 385, 420, 421 Wrack Family : bladder- wrack, 488, 489 Wrapping for bottles, 280 Writing-inks, 294 Writing-paper, 224 Xyridales, Yellow-eyed Grass Or- der Yarn, 223 Yeast, 155 Yeast Family: yeast, 155 Yeast Fungi, 495 Yellow Ladies' Slipper, 220; Y. Locust, 2.59 Yellow-eyed Grass Order, 397 Yew, 212, 213, 392, 393, 426, 427 Yew Family, 392, 397, 426, 427: yew, 213 Yokes, 244, 263 Yoke-spore algae, evolution of, 558 Zanzibar Copal-tree, 289, 290, 366 Zea Mays, Maize Zingiber officinale, Ginger Zygomycetes, Pin-mold Fungi Zygospore, 478, 497, 511 Zygote, 482, 512 THIS BOOK MAY BE KEPT FOURTEEW DAYS A FINE WILL BE CHARGED FOR EACH DAY THE BOOK IS KEPT OVERTIME. PLANTS AND THEIR USES bv Frederick L. Sargent, PLANTS AND THEIR USES by Frederick L, Sargent FOftS$TA INSTITUTE fot OCEAN MOUNTAIN STUDIES 6205 FRANKTOWN ROAD CMSOH CITY, NfVADA 89701 The Meter, for LENGTH THE METRIC SYSTEM. Units. The most commonly usfd divisions and multiples. Centimeter (cm),- i/ioo meter; Milliineter (mm), l/iooo meter; Micron (/(), i/iooo millimeter. The micron is the unit in micrometry. Kilometer, looo meters; used in measuring roads and other long distances. Thf Tram for i ^^'^^'S''""^ ("^g)' i/iooo gram. ' - Kilos^ram, lOOO grams, used for ordinary masses, like ^^'^-^•^"■^ ( groceries, etc. The Liter, for j Cubic Centimeter (cc), i/iooo liter. This is mc^re CAPACITY. . .. ( common than the correct form, Milliliter. Divisions of the units are indicated by Latin prefixes: deci, i/io; centi, l/ioo; /;/////, i/iooo. Multiples are designated by Greek prefixes: deka, lo times; hecto, lOO times; kilo, lOOO times; myria, 10,000 times. TABLE OF METRIC AND ENGLISH MEASURES. Meter = 100 centimeters, 1000 millimeters, 1,000,000 microns, 39.3704 inches. Millimeter (mm) =: 1000 microns, i/io millimeter, i/icoo meter. 1/25 inch, approximately. Micron (//) (unit of measure in micrometry) = 1/1000 mm, i/inooooo me- ter {0.000039 inch), 1/25000 inch, approximately. Inch (in.) = 25.399772 mm (25.4 mm. approx.). Liter = 1000 milliliters or 1000 cubic centimeters, i quart (approx.). Cubic centimeter (cc or cctm) = i/iooo liter. Fluid ounce (8 fluidrachms) = 29.578 cc (30 cc, approx.). CIram — 15.432 grains. Kilogram (kilo) = 2.204 avoirdupois pounds (2l pounds, approx.). Ounce Avoirdupois (437i grains) = 28.349 grams / (30 grams, Ounce Troy or Apothecaries' (480 grains) = 31. 103 grams )" approx. ). TEMPERATURE. To change Centigrade to Fahrenheit: (C. X |) +32 = F. For example, to find the equivalent of 10° Centigrade. C. = 10°, (10° X |) + 32 = 5°° ^■ To change Fahrenheit to Centigrade: (F. — 32°) X | = C. For example.to reduce 50 Fahrenheit to Centigrade, F. = 50°, and (56°— 32°) x | — 10° C. ; or - 40' Fahrenheit to Centigrade, F. = —40% (- 4°°— 32°) = - 72°, whence — 72" X » = - 4°° C. — From "■The Microscope" {by S. H. Gage) by permission. iVi mASUltmS Uf 1 Jl,.\U-Jl-KATl . Kl;- - . o ^ — rH ^ Centigrade Fahrenheit Centigrade Fahrenheit " ~ o o o o + 100 +212 + 16 + 60.8 r: '"' — 90 194 15 59 =: -^ 80 176 14 57.2 zz n -" 70 158 13 55.4 ~ " O - 60 140 12 53.6 E — 50 122 11 51,8 = -' ~ 49 120.2 10 50 =_ ~ 48 118.4 9 48.2 zz - 47 116.6 8 46.4 r^ 46 114.8 7 44.6 ^ — 45 113 6 42.8 — -^ - 44 111.2 5 41 — o ZZ "H 43 109.4 4 39.2 Er- —_ 42 107.6 3 37.4 - -^ 41 105.8 2 35.6 — 35 = CO - 40 - 104 + 1 +33.8 =~ en zz uu - 39 102.2 0 +32 - — 1- ;i » LU GO UJ — 38 100.4 —1 + 30.2 E_ s X 37 98.6 2 28.4 = 1- z" _ 36 96.8 3 26.6 - z. - L- UJ — 35 95 4 24.8 zz O - 34 93.2 5 23 E 33 91.4 6 21.2 Lz '-o — 32 89.6 7 19.4 =— ~: 31 87.8 8 17.6 zz ~- 30 86 9 15.8 zz o n\ - 29 84.2 10 14 E- - 28 82.4 11 12.2 E Ji 27 80.6 12 10.4 — -f ' 26 78.8 13 8.6 E- - 25 77 14 6.8 = — : 24 75.2 15 5 E " - 23 73.4 16 3.2 n— rH - 22 71.6 17 1.4 - J^ 21 69.8 18 — 0.4 E "' - 20 68 19 2.2 ~ - 19 66.2 20 4 - ^ 18 64.4 30 22 1^ ~ —I 17 62.6 —40 —40 t ^ : If fif 4 % ij m ■■■'■ 'Si :-*' \f! .»? »« 1.1 ff .-■«