S20 



SUBJECT INDEX 



Parasites — cont. 



236 ; transpiration af, 228 ; 

 water supply of, 220, 225, 

 228 

 compared with graft, 225 

 branch, 221, 222, 234, 238 ; 

 partial, 219 ; root, 219, 229, 

 230, 232, 238 

 Parasitism, of mycorhiza, 247, 256 

 origin of, 237 sqq. 

 opportunities for, 257 

 and origin of sex, 324 

 experimental, 238 

 Parenchyma, palisade, 84, 121, 153, 

 163 ; spongy, 84, 126, 153, 

 163 

 Parthenocarpy, 406 

 Parthenogenesis, 321, 326, 462 



origin and causation of, 328 

 Perennation and mycorhiza, 257 

 Periodicity, of floral movements, 

 349 ; of leaf fall, 451 ; of leaf 

 movements, 204 ; of stomatal 

 movements, 109 

 Phanerophytes, 451 

 Photosynthesis, 79 



also under Assimilation 

 Phototropism, 121 



of leaf, 120, 122, 123 ; of 

 peduncle, 404 ; of roots, 295 

 Phyllodes, 194 

 Phyllotaxy, 1 1 5 sqq. 

 Pitchers, of insectivores, structure of, 



271, 274 ; origin of, 281 

 Pneumatophores, 43 

 Poisonous plants, 309 

 Pollen, 344 sqq. 



of submerged flowers, 345, 379 ; 

 of wind-pollinated flowers, 



376 

 germination of, 346 ; protection 

 of, 348, 350 sqq. ; reception 

 of, 352, 353 ; structure of, 

 344 ; viability of, 345 



Pollen tube, growth of, 352, 357 ; 

 origin of, 353 



Pollination, by bats, 375 ; by birds, 

 373 sqq. ; by insects, 355 

 sqq-, 398 ; by insects laying 

 eggs, 370 sqq. ; by snails, 

 375 ; by water, 378 ; by wind, 

 375 ^QQ-> 383, 384. 398 



Pollinia, 345, 387 



Post-floral changes, 401 sqq. ; in 

 gymnosperms, 406 



Post-floral movements, 403 



Porometer, 167 



Potometer, 167 



Prairie plants, root systems of, 29 

 Predetermination, 444, 458 

 Propagation, 314 

 Protection, of buds, 450 ; of fruit, 



404 ; of pollen, 350 

 by ants, 309 

 against frost, 449 ; against 



grazing animals, 307, 312 ; 



against larvae, 312 ; against 



parasites, 313 ; against snails, 



307 

 specialisation of, 306 

 and immunity, 313 

 chemical, 308 ; mechanical, 307 



Ramblers, 295, 304 

 Raphides, 308 

 Rejuvenation, 321, 462 

 Reproduction, 314 sqq. 



and age of plant, 457 ; and 



external factors, 458 sqq. 

 asexual, significance of, 320 ; 

 sexual, significance of, 320, 

 462 

 Resupination, 292 

 Rhythm, under Periodicity 

 Roots, 22 sqq. 



aerating system of, 43 ; branch- 

 ing of, 24 ; growth of, 23 ; 

 solvent action of, 68 

 buds on, 460 ; effect on, of 

 mycorhiza, 245, 248, 251, 252 

 absorbing, 24 ; anchoring, 24 ; 

 assimilating, 198 ; buttress, 

 287 ; contractile, 288, 289 ; 

 prop, 287 

 Root climbers, 295 

 Root hairs, 47 



of aquatics, 49 



absent from mycorhiza, 245 ; 

 persistent, 48 

 Root nodules, 258 sqq. 

 Root systems, 25 sqq. 



of aquatics, 36 ; of broad- 

 leaved trees, 26 ; of cactuses, 

 34 ; of chaparral plants, 32 ; 

 of conifers, 26 ; of desert 

 plants, 33 ; of forest plants, 

 33 ; of epiphytes, 71 ; of 

 herbaceous plants, 25 ; of 

 mangroves, 43 ; of marsh 

 plants, 36 ; of moorland 

 plants, 191 ; of prairie plants, 

 29 ; of sandhill plants, 32, 46 

 extent of, 28 ; mechanical 

 features of, 286 sqq., 294 ; 

 modifications of, 37 sqq. 



