380 



INDEX 



Pezizales, 293 

 Phaeophyceae, 278 

 Phaeosporales, 278 

 Phallales, 302 

 Phallus, 303 

 Phloem, 47, 97-100 

 Phoradendron, as parasite, 172 

 Phosphorus, importance of, 31, 168 

 Photosynthesis, 20, 69-74, 127 



by-product of, 73 



energy of, 70 



importance of, 69, 128 



materials of, 69 



mechanism of, 70 



products of, 72 

 Photosynthetic equation, 73 

 Phototropism, 158, 159 



negative, 158 



neutral, 158 



positive, 158 

 Phycocyanin, 265 

 Phycoerythrin, 282 

 Phycomycetes, 289 

 Phyllotaxy, 90 

 Phylogeny, 2, 257 

 Physcia, 304 

 Physiology, 3 

 Pileus, 299, 301 

 Pine, cambium of, 147 



cones of, 352, 353 



gametophytes of, 345, 347 



pollen of, 186 



wood of, 109 

 Pistil, 185 

 Pitcher plant, 173 

 Pith, 95, 96 

 Pits in wood cells, 101 

 Plankton, 276 

 Plant association, 169 



foods, 117-122 



geography, 3 



kingdom, evolution of, 244 

 size of, 243 

 survey of, 11-16 

 Plants, compared with animals, 244 

 Plasmolysis, 55 

 Plastids, 45 

 Platanus, twig of, 102 



Plate, in mitosis, 141 



Plectascales, 295 



Pleurococcus, 245, 267 



Pleurotus, 13 



Pliny the Elder, 4 



Plowrightia, 294 



Plumule, 198, 199 



Plurilocular sporangium, 278, 279 



Pod, 199 



Pole, in dividing cell, 141 



Pollen, 185, 186, 346 



chamber, 350 



tube, 196, 197, 347 

 Pollination, 193-196 



by insects, 194 



by wind, 194 

 Polypetalous corolla, 190 

 Polypodiuni, 327 

 Polyporaceae, 301 

 Polysepalous calyx, 190 

 Polysiphonia, 283 

 Polytrichum, 14, 321 

 Pome, 200 

 Pond scums, 275 

 Pore fungus, 301 

 Porella, 316 

 Postelsia, 278 



Potassium, importance of, 31. 168 

 Potato, starch grains of, 120 



tuber of, 94 

 Potential energj^, 69, 125 

 Primary tissues, 149 

 Primitive plants, 244 

 Primula, flower of, 195 

 Procarp, 282, 283 

 Proembryo, 354 

 Promycelium, 297, 298 

 Prophase of mitosis, 140 

 Proserpinaca, "amphibious" plant 



of, 164 

 Proteins, 121 



digestion of, 124 



synthesis of, by green plants, 122 

 Prothallus, of fern, 330, 332 

 Protococcales, 267 

 Protonema, 320 

 Protoplasm, 19, 44, 124 

 Protoplast, 44 



