None
The germination of the dicotyledonous seed occurs in one of two methods. In the first of these, the cotyledons, which are thick and fleshy, remain underground. When kept warm and moist the seed absorbs water and swells, the radicle makes its way out of the micropyle, the testa bursts, and the plumule makes its way upwards, the epi- cotyl, or part between the cotyledons and the first foliage leaf or leaves, circumnutating and emerging in the form of an arch, owing to the greater growth of one side. After reaching the air the growth changes, the greatest increase passing to the opposite side, so that the epicotyl straightens itself. During this time it subsists upon the nourishment stored in the cotyledons in the shape of reserve materials. We have already discussed the means whereby these digestive and nutritive changes are brought about, the agencies which effect them, and the various transformations which are met with. As the cotyledons remain under- ground this process is called hypogean germination. In the other method — that of the so-called epigean germina- tion— the cotyledons sooner or later rise above the ground and become green, the hypocotyl behaving as does the epicotyl in the first case. These are frequently, though not always, albuminous seeds, in which the nutritive matter is KEPKQDUCTION 449 stored outside the embryo. In both cases the root makes its way into the soil by virtue of its geotropism and aphe- liotropism, aided by the movement of circumnutation, and by the adhesion of the root-hairs to particles of the soil. In some Monocotyledons the upper part of the single cotyledon remains in the seed and absorbs the nutriment from the endosperm, while its base elongates and thrusts the young plant downwards. Sometimes the usual alternation of sexual and asexual reproduction in the higher plants is interfered with by the substitution of the vegetative method for one of them.. In the phenomenon of apospory, noticeable in some Ferns, we have small prothallia developed on the back of the leaves in the place of spores. This is a case of tbe production of a bud instead of an asexual cell. Apospory is also known to occur among the Mosses. In the Ferns, again, the sporophyte sometimes arises as a bud or vegetative outgrowth upon the prothallium, a phenomenon known as apogamy. There is another kind of apogamy known, which is generally termed parthenogenesis. It occurs among the Fungi, where, as in Saprolegnia, oospheres are formed in oogonia, which do not become fertilised, and yet have the power of growing out into new plants. In some species of Mucor which normally exhibit the fusion of particular hyphae and the admixture of their contents, or gametes, a variation of the process is observed which comes under this category. Instead of two gametangia meeting, and their contents fusing, to form the zygospore, these organs are de- veloped singly and do not coalesce. In this case the fer- tile cell, which should be a zygote, is produced partheno- genetically in each, and is known as an azygospore. Another variety of parthenogenesis, which resembles the apogamy of the Ferns, occurs in Ccelebogyne, where an embryo is produced in the embryo-sac but without pollina- tion or fertilisation. No sexual cell is produced, but there occurs a vegetative budding of one or more of the cells 29 450 VEGETABLE PHYSIOLOGY of the nucellus of the ovule, the buds growing into the cavity of the megaspore and there developing into embryos. This is not quite the same thing as the apo- gamy of the Fern, as the new sporophyte arises as a bud upon part of the sporangium — that is, upon the parent sporophyte and not upon the gametophyte. It is really a curious variation of vegetative propagation. INDEX Abnormal methods of food supply, 183 Absorption, of water 18, 68, of food materials 126, of salts 132, of gases 137, of organic food 135, 183 ; conditions of continuous, 130 ; facilitated by C0.2 131, by acid sap 131 ; strength of salts absorbed, 132 ; varied amounts of salts ab- sorbed, 133 Acclimatisation, 366 Acer, 87 Aconitum, 439 JRthalium, 9 After-effect of stimulation, 398, 408 Agave, 239 Aggregation, 390, 405 Air-chambers, in Isoe'tes, 106; in Marsilea, 107 ; in submerged plants, 108 ; in grasses, 109 ; in leaf of heath, 112 Albumen, 434 Albumin, 162 Albumoses, see Proteoses Alburnum, 72 Alcliemilla, 76, 83 Alcohol, 256, 301 Aleurone grains, 235, 236 Alkaloids, 270 Alternation of generations, 426 Aluminium, 129, 175 Amidated fatty acids, 270 Amido-acids, 167 Ampelopsis, 387 Amphibious plants, 335 Amygdalin, 238, 253 Anabolism, 123, 258 Anaerobic plants, 304 Anaesthetics, action of, 408 Analysis, destructive, 129 Ananassa, 252 Anemophilous flowers, 439 Antheridia, 424 Antherozoids, 423 ; motion of, 435 ; attraction of, 436 Anthoceros, 195 Anthocyan, 267, 322 Anthoxanthum, 442 Antipodal cells, 432, 434 Apheliotropism, 377 Aphydrotropism, 391 Apogamy, 449 Apogeotropism, 380 Apospory, 449 Apostrophe, 363 Aquatic plants, structure of, 331 Arabinose, 42 Archegonia, 425 Ascending sap, 66 Ascidia, 189 Ascogonidia, 420 Ascomycetes, 424 Ascospores, 420 Asexual reproductive cells, 419 Ash of plants, composition of, 129, 171 ; effect of its constituents on vegetation, 177 Ash of proteins, 161 Asparagin, 167 ; as a reserve material, 238; as a product of digestion, 252 Aspergillus, 250 Asphyxiation, 300 Assimilation, 123, 257 ; (of carbon dioxide, see Photosynthesis) Auxanometer, 313 Azolla, 195, 440 Azygospore, 449 BACH on photosynthesis, 154 ; on nitrogen fixation, 167 Bacteria, 2, 3 Bacterium termo, relation to oxygen, 157, 392 BAEYER, on photosynthesis, 151 Bambusa, 29 Bark, 20, 226 Bast, 22, 52 ; function of, 213, 213, * 218 452 VEGETABLE PHYSIOLOGY Bauhinia, 376 Begonia, 417 Bentinckia, continuity of proto- plasm in, 16 Benzol, 168 Berberis, 383, 398 Bertholletia, 177 Betula lenta, 254 Biennial plants, 211 Bignonia, 377 Bleeding (of stems), 83, 86 Bloom (of fruits), 50 BOKOBNY on action of chlorophyll apparatus, 150 Botrychium, 185 BOUILHAC, 152 Bromelin, 252 Bromine, 129, 175, 181 BROWN and MORRIS on photosyn- thesis, 153 Bryophyllum, 417 Buckwheat, 173, 181 Budding, 205, 413 Buds, position of leaves in, 314 Bye-products, 261, 269 Cabomba, 335 Calcium, in ash, 129, 136, 175 ; mode of absorption of, 178 ; effect of, on herbage, 179 Calcium pectate, 46 Calcium, salts of, in cell-wall, 50, 286 Calyptra, 447 Cambium, 238, 308 Cane-sugar, 153 ; as reserve material, 233 ; digestion of, 250 ; as attrac- tion for antherozoids, 393 Capillarity, 81 Carbohydrates, 40, 129 ; formation of, 151 ; theories of construction of, 151, 154 ; course of process of construction of, 212 ; translocation of, 213 ; resting and travelling forms of, 215 ; storage of, 228 Carbon dioxide, absorption of, 114, 139 ; exhalation of, 288 ; relation to oxygen absorbed, 285 ; inca- pable of nourishing protoplasm, 122 ; temperature at which de- composition by chloroplast begins, 150 ; optimum percentage, 158 Carbon monoxide as a stage in photosynthesis, 151 Carica Papaya, 252 Castor oil plant, see Ricinus Casuarina, 146, 445 Cell, 2, 3; various applications of the term, 16 Cell-division, 412 Cell-wall, of protoplast, 2 ; properties of, 39 ; of Fungi, 40 ; theories of its composition, 43, 44 ; thicken- ing of, 44 ; stratification of, 44 ; formation of, 262, 415 Cellulose, 39 ; properties of, 40 ; varieties of, 40 ; as reserve material, 233, 234 Centrifugal force, influence on di- rection of growth, 382 Centrospheres, 413 Ceramium, 16 Chara, 350 Chelidonium, 1 Chemotaxis, 393 Chitin, 40 Chlamydomonas, 348, 351 Chlorine, 175, 181 Chlorophyll, 141 ; condition in chloroplasts, 147 ; solvents of, 141 ; properties of, 142 ; spec- trum of, 143 ; analyses of, 144 ; conditions of formation of, 148 ; action of, dependent on light, 149 ; relation to iron, 174 ; secretion of, 266 Chlorophyll apparatus, 141 ; action of, 149 ; absorption of energy by, 279, 284 Chloroplasts, 124, 139, 141 ; distri- bution of, 145 ; structure of, 146 ; functions of the two components of, 156 ; effects of varying pres- sures of carbon dioxide on, 157 ; inhibition of, 158 Chlorosis, 149 Chlorotic plants, 267 Chromatin, 8 Chromosomes, 413 Chroococcus, 9 Cilia, 1, 2, 345 Ciliary motion, 345 Circulating food-stuffs, 212 Circumnutation, 315 ; dependent on rhythm, 353 Cladium, 21, 29 Cleistogamy, 443 Cobalt, 175 Cobalt chloride as test for watery vapour, 90 Ccelebogyne, 417, 449 Coenocytes, structure of, 10, 11 ; skeleton of, 39 ; reproduction of, 416, 421 Cold, injurious effects of, 327 Coleoclicete, 427 INDEX 453 Collenchyma, 21, 52 Commensalism, 195 Conducting system, 21 Conjugation, 425 Constructive processes, anabolic, 258 ; katabolic, 260 Contact, stimulus of, 383 Convolvulus, 387 Copper, 129, 175 Cork, 20, 49 Cortex, 226 Crassulacece, 292, 296 CRATO on photosynthesis, 154 Crystalloids, 237 Crystals of protein, 237 Cucumis, 252 Cucurbita, 87 Cupulifera, 197 Curvature (of stimulated roots), 385 Cuscuta, 203, 342, 388 Cuticle, 48 ; influence of on tran- spiration, 20 Cuticularisation, 20, 48 Cutin, 49, 50 Cutleria, 423 ' Cycas (antherozoids of), 437, 446 Cyclamen (apheliotropism of pe- duncles of), 377 Cystocarps, 427 Cystoliths, 51, 273 Cytase, 248, 251 Cytoplasm, 5 CZAPEK, 400 DARWIN, on localisation of sensitive- ness, 378, 382 ; on tendrils, 385 ; on twining stems, 387 ; on Drosera, 405 DARWIN, F., and PERTZ on induced rhythm, 394 Day and night, influence of alterna- tion of, 371 Delphinium, 439 Descending sap, 217 Desmids, 379 Desmodium gyrans, 354, 371 Diageotropism, 380 Diaheliotropism, 377 Diastase, 248 ; function of, 249 ; in pollen, 444 Diaster stage in mitosis, 415 Diatoms, 347 Dichogamy, 441 Diclinism, 442 Digestion, 123 ; by Nepenthes, 190, 247 ; by Drosophyllum, 191 ; by Pinguicula, 191 ; by Dioncca, 194, 247 ; by Drosera, 193, 247 ; by Bacteria, 194 ; of reserve ma- terials, 242 ; by Fungi, 257 Dimorphism, 443 Dioecious plants, 442 Dioncea, 135, 191, 193, 247, 348, 369, 383, 390, 398, 401, 404, 408 Dodder, see Cuscuta Dorsiventral structures, 314 Double fertilisation, 437 Drosera, 135, 192, 247, 348, 383, 390, 393, 404, 405, 406 Drosophyllum, 191 Duramen, 72 Ectocarpus, 423 Ectoplasm, 5 Egg apparatus, 432 Elaioplasts, 240, 265 Elodea, 6, 349 Embryo, nutrition of, 119 Embryo-sac, 431 Emulsin, 248, 253 Endodermis, 69 Endo-skeleton, 29 Endosperm, 431, 434 Energy, expenditure of, in photosyn- thesis. 156, 276 ; expenditure of, in transpiration, 275, 281 ; in constructive processes, 276 ; in growth, 276 ; in movement, 277 ; in production of heat 277, of light 279 ; sources of, 279, 321 ; potential and kinetic forms of, 281 ; liberation of, 281 ; distri- bution of, 282 ENGELMANN, on evolution of oxygen in different parts of the spectrum, 157 ; on purple bacteria, 159 Entornophilous flowers, 439 Environment, nature of, 329 Enzymes, 138, 244 ; preparation of, 256 ; secretion of, 261 ; in pollen, 444 Ephedra, 50 Epidermis, characters of, 48 Epinasty, 314 Epiphytes, 195, 339 Epistrophe, 363 Equatorial plate, 414 EquisetacecB, 50 Equisetum, sclerenchyma of, 27, 29 ; air-spaces in, 108; chloroplasts in, 146 Erepsin, 248 Erianthus, 29 ERLENMEYER on photosynthesis, 154 Erythrophyll, 144 454 VEGETABLE PHYSIOLOGY Erytkrozym, 248, 254 Etiolation, 360 Etiolin, 148 ; in photosynthesis, 157, 174 ; antecedent of chloro- phyll, 267, 360 Euonymus, 148, 266 Euphorbia^ 231 EWAKT on inhibition of chlorophyll apparatus, 158 Exhaustion, 408 Exodermis, 21 Fat, 129 ; origin of, 170 as reserve material, 240 ; digestion of, 254 ; secretion of, 265 Fatigue, 408 Fermentation, 301, 325 Fermentative power of protoplasm, 302 Ferments (soluble), see Enzymes ; (microbic), 301 Fern, skeleton of, 25, 26 Fertilisation, 425, 438 ; stimulating effect of, 447 Fimbristylis, 27, 29 Flaccidity, 64 ; removal of by inject- ing water 91, by checking tran- spiration 96 Flagella, 2 Flowers, opening and closing of, 314, 376 Fluorine, 175 Food, its nature, 118; formation of, 141 ; conditions of continuous formation of, 222 Food materials, relation to food, 121 ; mode of absorption, 126, 128 Formaldehyde, as stage in photosyn- thesis, 151, 154 ; in construction of protein, 167 Formic acid, 154 Free-cell formation, 416 Frost, action of, 327 Fruit, formation of, 447 Fucacece, 425 Fungi, composition of cell-walls of, 40; constructive powers of, 184; digestive powers of, 194; haus- toria of, 205 Funkia, 239 Fusarium, 250 Gametangia, 423 Gametes, 421 Gametophyte, 426 GARREAU on absorption of oxygen by plants, 286 Gaseous interchanges, 103 Gases, mode of absorption of, 103 ; movements of, in plants, 113, 114 ; currents of, affected by external conditions, 116 ; absorption of, 137 Gaultherase, 248, 254 GAUTIER on chlorophyll, 144 Gelatin, 160 Gemmae, 417 Gemmation, 413 Geotropism, 380, 394 Germination, of pollen, 444 ; of seeds, 448 Ginkgo, antherozoids of, 437, 446 Glands, 245 Gliadin, 164, 238 Globoids, 237 Globulin, 162 Glochidia, 441 Glucase, 248, 250 Glucosides as reserve material, 238 Gluten, 237 Glutenin, 164, 238 Glycogen, 232 Gonidangia, 419 Gonidia, 419 Grafting, 205 Grape-sugar as reserve material, 233 Grasses, construction of stem of, 109 Growing-points, 76, 308 Growth, 210, 304; localisation of, 305, 308, 313 ; conditions of, 308 ; course of, 309 ; grand period of, 310, 313; of leaf, 312; daily period of, 313, 353 Gums, 51 Haustoria, 201, 205, 342 Health, 358, 365 Heat, liberation of, 276 ; absorption of, 321 ; conduction of, 325 ; regulation of, 326 ; resistance to, 328 Heaths, rolled leaves of, 338 Hedysarum, 354 ; also see Desmo- dium Helianthus, 91 Heliotropism, 377, 394, 395 Hepaticce, 391 Heterospory, 429 Heterostylism, 443 Honey, 440 Hop, 387 INDEX 455 Hori-E SEYLER on chlorophyll, 144, 177 Humus, 67 Hybridisation, 446 Hydrocyanic acid, 168, 254 Hydrogen peroxide in photosynthe- sis, 154, 156 Hydrophilous flowers, 439 Hydrotropism, 391 Hypnum, 185 Hyponasty, 314 Individual, 411 Insectivorous plants, 135 ; Utricu- laria, 187 ; Sarraccnia, 189 ; Nepenthes, 190 ; Drosophyllum, 191 ; Pinguicula, 191 ; Dioncea, 192, 193 ; Drosera, 192 Intercellular passages, 31, 32; for- mation of, 32, 104 ; function of, 34, 104 ; watery vapour in, 74 ; in Isoetes, 106, 332 ; in Marsilea, 107, 334 ; relation to stomata, 111 ; ratio fo cellular tissue in leaves, 113 ; composition of air in, 113, 114 ; positive gaseous pressure in, 117 ; in aquatic plants, 331 Intercellular substance, 45 Inulase, 248, 250 Inulin, 232 Invertase, 248, 250, 444 Iodine, 129, 175, 181 Iron, in ash of plants, 129, 175 ; combinations absorbed, 136, 179 ; relation to chlorophyll, 149 ; function of, 178 Irritability, 358, 393 Isoetes, 106, 107, 332, 430 JUMELLE on decomposition of car- bon dioxide, 150 Juncus, 28, 29 Kachree gourd, 252 Karyokinesis, 413 Katabolism, 123, 258 Kephir, 196 Klinostat, 380 KNIGHT on action of centrifugal force on the direction of growth, 382 Laccase, 181, 299 Lactase, 250 Latent period of response to stimu- lation, 407 Lathrcca, 202 Laticiferous systems, 220 Leaves, sclerenchyma of, 27 ; rolled, 112 ; irritability of, 372 Lecithin, 177, 254 Leguminosce, cotyledons of, 40 ; absorption of nitrogen by, 134, 165, 196 ; irritability of leaves of, 371 Lenticels, 34, 76 Leucin, 167 Leucoplasts, 148, 229 Lichens, 196 Light, influence of, on transpiration, 95 ; absorption of, by chlorophyll, 143, 279 ; necessary for formation of chlorophyll, 148 ; action in photosynthesis, 149, 156 ; tonic influence of, 359 ; effect of, on differentiation of leaves, 360 ; effect on growth, 364 ; lateral, 377 Lignin, 47, 50, 271 Lipase, 248, 254 Lithium, 175 Locomotion, 276, 347, 348 Lycopodium, 40, 185 Lythrum, 443 MACALLUM on composition of nucleus, 178 Magnesium, in ash, 129, 136, 175; mode of absorption of, 178 Malic acid, attraction for anthero- zoids, 392 Maltase, 248 Malto-dextrin, 249 Manganese, 129, 175, 181 Marchantia, photo-epinasty of, 363, 379 Marsilea, 51, 107 Massula of Azolla, 441 Medullary rays, influence of, on transpiration current, 81 ; as store- houses of reserve material, 225 Megaspores, 429 Melampyrum, 203 Melibiase, 250 Melizitase, 250 Mesocarpece, 422 Mesocarpus, 357, 363, 403 Metabolism, 6, 123, 258 Metapectic acid, 42 Metapectine, 42 Meta-proteins, 163 Methane, 168 456 VEGETABLE PHYSIOLOGY Micellae ot cell-wall, 43 Micrococcus Urece, 255 Microspores, 429 Middle lamella, 45 Mimosa, 62, 355, 357, 369, 371, 383, 388 Mimulus, 383 Mistletoe, 199, 343 Mitosis, 413 MIYOSHI on chemotaxis, 393 Monoblepharis, 424 Monoecious plants, 442 Monotropa, 198 Moorland plants, 338 Movements, of protoplasm, 6, 348 ; for capture, 191, 193; of multi- cellular organs, 348 Mucilage, 51, 234 Mucor, 449 Mycodermd aceti, 256 Mycorhiza, 198 Myriophyllum, 117 Myronate of potash, see Sinigrin Myrosin, 248, 253 Myxomycetes, 49, 346, 391, 392, 393 NAEGELI, theory of composition of cell-wall, 43 Nectar, 272 Nectary, 62, 440 Negative pressure, in wood-vessels, 89, 91 ; influence of, on move- ments of gases, 116 Neottia, 185 Nepenthes, 135, 190, 247 Nervous mechanisms, 397 Nickel, 175 Nicotiana, 373 Nitella, 6, 350 Nitrates, 129, 160 Nitrification, 134, 158 Nitrogen, absorption of, 113, 133; in proteins, 161 ; fixation of, by leguminous plants, 134, 165, 197, by Algse, 165 Nostoc, 12, 195 Nuclear spindle, 414 Nuclein, 8, 175, 177 Nucleolus, 8 Nucleoplasm, 8 Nucleus, 5 ; position in cell, 7 ; structure of, 8 ; definitive, 433 ; generative, 437 Nutation, 315 Nyctitropic movements, 325, 372, 374, 376 Nymphaa, 108, 332 (Edogonium, 427 Oil, see Fat Oncidium, 239 Oogonia, 424 Oospheres, 423 Oospore, 425 Optically active compounds, 153 Opuntia, 292, 296 Ornithogahtm, 239 Orobanchacece, 342 Orobanche, 202 Orthocarbonic acid in photosyn- thesis, 154 Osmosis, 55 ; in adult cells, 60 ; from veins of leaf, 74; influence of, on transpiration current, 100, 102 Ouvirandra, 332 Ovule, 431 Oxalic acid, 296 Oxalidacece, 371 Oxalis acetosella, 362 Oxidases, 255, 259, 299, 300 Oxidation, 299 Oxygen, mode of absorption by plants, 15, 31, 115 ; influence of, on action of roots, 85; proof of absorption of, 287 ; relation of absorption of, to exhalation of carbon dioxide, 291 ; variation in amount of, as affecting respiration, 297 P<zonia, 40 Pangium, 168 Papain, 252 Paraheliotropism, 362 Parapectine, 42 Parasites, 121, 340 Parasitism, 185, 196, 200 Paratonic influence of light, 359 Parnassia, 441 Parthenogenesis, 449 Passiflwa, 385, 398 Pectase, 248, 251, 252 Pectic acid, 42 ; relation to middle lamella, 46 Pectine, 41 Pectose, 41 Pediastrum, 12 Pelvetia, 18 Pennisetum, 27, 29 Pepsin, 248, 251, 252 Peptone, 163 Perception, 406 Periodicity of root-pressure, 87, 356 Perisperm, 434 INDEX 457 PFEFFER, on water-culture, 185 ; on localisation of sensitiveness, 382 Phajus, 231 Phalaris, 378, 398, 400 Phosphorus, in proteins, 129, 175 ; mode of absorption of, 136 ; asso- ciated with nucleus, 177 Photo-epinasty, 363 Photosynthesis, 150 ; theories of, 151 ; not carried out by fungi, 159 Phototaxis, 379 Phototonus, 358 Pinguictila, 191 Pitcher-plants, see Insectivorous plants Planogametes, 422 Plantago, 442 Plasmatic membranes, 6, 57, 59 Plasmodium of Myxomycetes, 4, 9, 346 Plasmolysis, 59 Plastids, 5 Polar nuclei, 432 Pollen grain, germination of, 444 Pollen tube, 433, 437 Pollination, 438'; methods of, 439 Polyembryony, 437 Polygamous plants, 442 Polygonum, photo-epinasty of, 363 Polymerisation of aldehydes, 152 Polytrichum, 26 P&rlieria, 391 Positive pressure of gases in inter- cellular reservoirs, 117 Potamogeton, 31 Potassium, in ash, 129, 136, 175 ; condition of, in soil, 136 ; mode of absorption of, 177 ; function of, 179 Potometer, 97 Predominant form of plants in different groups, 428 Prepotency, 443 Primula, 269 Procarpium, 424 Protandry, 441 Proteins, 160 ; composition of, 161 ; crystals of, 161 ; reactions of, 161 ; coagulated, 162 ; construction of, 164 ; translocation of, 215, 218 ; storage of, 216 Proteoclastic enzymes, 248, 251 Proteoses, 163 Protococcus, 9 Protogyny, 442 Protoplasm, composition of, 6 ; movements of, 6, 349 ; properties of, 12 ; continuity of, through cell-walls, 15, 404; regulation of osmosis by, 60, 101 ; relation of, to respiration, 294 ; nutritive sub- stances for, 120 ; fermentative activity of, 244, 256, 302 ; per- meability of, by water, 351, 403 Protoplasts, structure of, 2 ; arrange- ment of, in multicellular plants, 3 Prumts, 87, 253 Prussic acid, 238, 253 Pseudopodia of Myxomycetes, 4, 346 Pulvinus, 62, 355, 374, 389 Pythium, 424 Kadiation, 278, 324 Raffinose, 233 Rafflesia, 203 Eaphides, 273 Rectipetality, 318 Reductases, 259 Reflex action, 405 Rennet, 248, 253 Reproduction, 411 ; relation to growth, 412 ; vegetative, 417 ; asexual, 418 ; sexual, 421 Reserve materials, 221 Reservoirs, of air, 106 ; of food, 138, 222 Resin, 269 Respiration, 289 ; gaseous inter- changes of, 285 ; masked by photo- synthesis, 286 ; loss of weight in- volved in, 289 ; intensity of, 291 ; nature of the process of, 293 ; relation of, to metabolism, 294 ; influence of external conditions on, 296 ; of seeds, 297 ; a source of energy, 298 ; intramolecular or anaerobic, 300 Respiratory quotient, 291 Rhamnase, 248, 254 Rhamnus, 254 Rhodophycea, 424, 427 Rhythm, of root-pressure, 83 ; nature of, 352 ; affected by s-timu- lation, 394 ; induced, 394 Ricinus, 190, 236 Ripening, 447 Robinia, 62 Root-hairs, 68 ; action of, 69 Root-parasites, 200, 343 Root-pressure, 71, 81, 82; rhythm of, 83, 87 ; method of measuring, 84, 87 ; amount of, 85 ; perio- dicity of, 87 Rush, construction of stem of, 110 Saccharomyces, see Yeast SACHS, on theory of transport of water in wood, 79 ; on a method 458 VEGETABLE PHYSIOLOGY of estimating rate of transpiration current, 81 Salvinia, 107 ; germination of mega- spore of, 430 Santalacecc, 200, 342 Saprolegnia, 393, 419, 449 Saprophytes, 121, 185, 341 Sarracenia, 135, 189 SAUSSUKE, DE, on Opuntia, 296 Saxifraga, 247; 336 Saxifragacea, 292 Scirpus, 27, 29 Sclerenchyma, 21, 25, 29 Scrophularia, 442 Scrophulariacea, 200, 342 Scutellum, epithelium of, 246, 249 Scyphanthus, 387 Secretion, 261 Seed, 429 ; formation of, 432 ; struc- ture of, 434 ; germination of, 448 Selaginella, prothallium of, 430 Selective power, 175, 182 Self-sterility, 443 Sense organs, 400 Sensitiveness, variations of, 378 ; localisation of, 378, 382, 401 ; delicacy of, 385, 409 ; mainte- nance of, 408 Sex, differentiation of, 423 Sexual cells, 421 Sieve-tubes, 170, 218 Silica, 50, 133, 273 Silicates, 136, 180 Silicic acid, ] 36 Silicon, 129, 136, 175, 180 Sinigrin, 239, 254 Skeleton, of plastid, 2, 37 ; of plant, 25,37 Sleep movements, see Nyctitropic movements Slime fungi, see Myxomycetes Sodium, 129, 136, 175, 179 Soil, composition of, 67 Sorus, 441 Spermatium, 436 Spermatozoids, 423 Sphagnum, 19 Spirogyra, 145, 152, 411, 427 Splachnitm, 185 Sporangia, 419 Spores, 419, 426 Sporophyte, 426 STAHL on method of detecting escape of watery vapour, 90 Starch, appearance of, during photo- synthesis, 153 ; probable cause of appearance of, in leaf, 156 ; forma- tion of, as evidence of activity of chlorophyll apparatus, 156 ; depo- sition of, in chloroplasts, 214, 228 ; removal of, from leaves, 224 ; storage of, 228 ; deposition of, by leucoplasts 229, by protoplasm 231 ; digestion of, 249 ; secretion of, 264 Statoliths, 383 Stele of root,. 69 Stimulation, 367 ; nature of, 369 ; purposeful nature of responses to, 369, 406 ; localisation of, 378, 386 ; after-effects of, 398 ; perception of, 406 ; latent period of, 407 Stimulus, nature of, 367 ; instances of rhythmic, 371, 374; of lateral light, 377 ; of gravitation, 379 ; of contact, 383; of moisture, 390; of oxygen, 392 ; chemical, 391 ; relationship of response to, 406 ; of fertilisation and pollination, 446 Stomata, 33, 75, 92 ; number of, in different plants, 94 ; mode of action of, 94 ; regulating influence of, on transpiration, 95 ; relation to gaseous interchanges, 112, 117 Storage of food, 211, 224 STKASBURGER, on composition of cell- wall, 43 ; on evaporation of water from cell-walls, 100 Stratification of cell-wall, 44 Style, reserve materials in, 227 Stylogonidia, 420 Stylospores, 420 Suberin, 271 Sugar, formation of, 153, 156 ; fer- mentation of, 301 Sulphur, in proteins, 161, 175 ; mode of absorption of, 136, 176 Sundew, see Drosera Sunlight, influence of, on transpira- tion, 95 Surplus food, construction of, 209 Symbiosis, 185, 195 Synergidse, 433 Tegumentary system, 19 Telegraph plant, see Desmodium Temperature, influence of, on root- pressure, 85 ; on transpiration, 96 ; on respiration, 296 ; range of, for different functions, 319 ; fluctua- tions of, 320 Tendrils, 385 Tensions, in hollow stems, 30 ; in growing organs, 316 Testa of seed, 434 Thalictrum, 439 INDEX 459 Thallophytes, 426 Theca, 427 Thermotonus, 359, 305 Thesium, 200, 388 TMIUIAZEFF on. relative values of the rays of the spectrum in photo- synthesis, 157 Tone, 359, 364, 366 Torsion of stems, 387 Tradescantia, 7, 350 Translocation, of food, 207; direc- tion of, 216 ; path of, 219 Transpiration, 75, 81, 88; methods of demonstrating, 88 ; amount of, 91 ; effect of excessive, 91 ; influence of external conditions on, 95; suction of, 100; functions of, 324 ; relation to etiolation, 361 Transpiration current, 78, 80 Trees, conditions of life of, 24 TREBOUX, 152 Trehalase, 250 TBEUB on construction of protein in Pangium, 168 Trichogyne, 424 Tropceolum, 83, 153 Trypsin, 248, 251, 252 Turgescence, 61 ; importance of, 64 ; methods of restoring, in flaccid tissue, 91 ; affected by shaking branches, 97 Turgor, 350 ; also see Turgescence Twigs, reserve materials in, 227 Twining organs, 387 Typha, 27, 29 Tyrosin, 167 Tyrosinase, 299 Ulothrix, 1, 411, 418, 421, 422 UNGEP. 