INDEX 
468 
Plant, naturalized, 1 
organs, 121-218 
perennial, 124 
tissues, 90-120 
zoophilous, 200 
Plantaginaceae, placentation in, 197 
Plasma membranes, 61, 73 
Plasmodiocarp, 231 
Plasmodium, 230 
Plasmolysis, figure illustrating, 69 
Plastids, 68, 69 
Platystemon, 332 
Plectascales, 256 
Plerome, 100, 122 
Pleurococcaceae, 232 * 
Pleurococcus, 232 
Pleuston, 409 
Plum, 209, 338 
Plumule, 121, 135 
Pod, 206 
Fig. of, 205 
Podophyllum, 327 
peltatum, 327, 328 
Polemoniales, 386 
Pollen, 54, ss, 193, 195 
maturation of, 55 
Pollen grains, Fig. of, 194 
germinating, 56 
pine, 83 
Pollination, 50, 56, 199 
Pollinia, 195 
Polyembryony, 59 
Polygala, 96 
lutea, 355 
senega, 354, 355 
Polygalaceae, 354 
Polygonaceae, 197, 321 
Polygonales, 321 
Polygonatum, 302 
Polygonum, 321 
Bistorta, 322 
Polypodiaceae, 292 
Polyporaceae, 274 
Polyporus, enzyme in, 95 
Polyporus, officinalis, 274 
Poly trichum commune, Fig. of, 285 
life history of, 286, 287 
Pome, 209 
of apple, Tig. of, 210 
Pomegranate Family, 371 
Ponteria, 380 
Poplar, 312 
Poppy, calyx of, 184 
Family, 332 
Populi Gemmae, 312 
Populus balsamifera, 312 
nigra, 312 
Pore Fungi, 274 
Porella, 283 
Potato, 391 
Potentilla, 185 
silvestris, 341 
Preflora tion, 181 
Prefoliation, 157, 158 
Prickles, 138 
Primula, style of, 199 
Primulaceae, placentation in, 197 
Principes, 299 
Principles of classification, 2, 3 
Privet, 381 
California, 127 
Proembryo, 242 
Promycelium, 267 
Proportions of stamens, 189 
Protective tissues, 120 
Proteins, 40, 89 
tests for, 89 
Prothallial cushion, 43 
Prothallus, 41, 290 
Protoascales, 251 
Protobasidiomycetes, 267 
Protococcales, 232 
Protonema, 41, 283 
Protophloem, 127, 129, 143 
Protophyta, 219 
Protoplasm, 62 
properties of, 62, 68 
Protoplasmic cell contents, 68-70 
