INDEX 
Paraheliotropism, 370 
Parapectine, 47 
Parasites, 127, 347 
Parasitism, 191, 196, 205 
Paratonic influence of light, 367 
Parnassia, 452 
Parthenogenesis, 459 
Passiflora, 394, 407 
Pectase, 254, 257 
Pectic acid, 47; relation to middle 
lamella, 51 
Pectine, 46 
Pectose, 46 
Pediastrum, 12 
Pelvetia, 22 
Pennisetum, 32, 33 
Peptase, 254, 257 
Peptone, 168 
Perception, 415 
Periodicity of root-pressure, 92, 364 
Perisperm, 444 
PreEFFreER, on water-culture, 172; on 
localisation of sensitiveness, 391 
Phajus, 237 
Phalaris, 386, 407, 409 
Phosphorus, in proteins, 135, 180 ; 
mode of absorption of, 141 ; asso- 
ciated with nucleus, 182 
Photo-epinasty, 371 
Photosynthesis, 155; theories of, 
156; not carried out by fungi, 
164 
Phototaxis, 388 
Phototonus, 366 
Phytol, 150 
Pinguicula, 197 
Pitcher-plants, 
plants 
Pitchers, 195 
Planogametes, 431 
Plantago, 452 
Plasmodium of Myxomycetes, 4, 10, 
354 
Plasmolysis, 64 
Plastids, 5 
Polar nuclei, 441 
Pollen-grain, germination of, 454 
Pollen-tube, 442, 446 
Pollination, 448 ; methods of, 449 
Polyembryony, 447 
Polygamous plants, 452 
Polygonum, photo-epinasty of, 371 
Polymerisation of aldehydes, 158 
Polytrichum, 31 
Porlieria, 400 
Positive pressure of gases in inter- 
cellular reservoirs, 121 
see Insectivorous 
467 
Potamogeton, 36 
Potassium, in ash, 135, 141, 180; 
_ condition of, in soil, 141 ; mode of 
+ pan of, 183; function of, 
85 
Potometer, 103 
Predominant form of plants in 
different groups, 437 
Prepotency, 453 
Primula, 275 
Procarpium, 433 
Protandry, 451 
Proteins, 165 ; composition of, 166 ; 
crystals of, 166 ; reactions of, 166; 
coagulated, 167; construction of, 
169; translocation of, 221, 224; 
storage of 222 — 
Proteoclastic enzymes, 254, 257 
Proteoses, 168 
Protococcus, 9 
Protogyny, 452 
Protoplasm, composition of, 6; 
movements of 6, 349; properties 
of, 12; continuity of, through 
cell-walls, 15, 413; regulation of 
osmosis by, 65, 107; relation of, 
to respiration, 299; nutritive 
substances for, 127; fermenta- 
tive activity of, 250, 261, 308; 
permeability of, by water, 359, 
412 
Protoplasts, structure of, 2; arrange- 
ment of, in multicellular plants, 3 
Prunus, 92, 259 
Prussic acid, 245, 259 
Pseudomonas, 204 
Pseudopodia of Myxomycetes. 4, 
354 
Pulvinus, 67, 362, 382, 399 
Pythium, 433 
Radiation, 284, 330 
Raffinose, 239 
Rafflesia, 209 
Raphides, 279 
Rectipetality, 324 
Reductases, 261, 266 
Reflex action, 415 
Rennet, 254, 259 
Reproduction, 420; relation to 
growth, 421; vegetative. 426; 
asexual, 427; sexual, 430 
Reserve materials, 227 
Reservoirs, of air, 113; of food, 130, 
228 
Resin, 275 
