INDEX 



289 



(influence of external condition on 

 growth), 140, 144, 150, 154, 159, 161, 

 165, 168 (induction and polarity), 182, 

 185, 214, 218 (periodicity), 223, 247, 

 249, 252, 257, 265-70 (resistance to 

 extremes) ; on nature of irritability, 

 75 ; on pressures exerted by growing 

 organs, 123-32. 



Pfitzer, 10, 18, 30; on growth of fungi, 17. 



Pfliiger, 105, 106, 107, 131. 



Phajus, formation of indigo in, 235 ; P. 

 grandifolius, freezing-point of, 242. 



Phaseolus, development of flower of, in 

 darkness, 91 ; duration of tissue-strains 

 in pulvinus of, 65 ; elongation of inter- 

 node of, 5 ; influence of correlation 

 on etiolation of, 99 ; strains in pulvinus 

 of, 62, 63 ; P. multiflorus, growth of 

 shoot of, 60 ; influence of etiolation 

 on, 89 ; temperature limits for growth 

 of, 76; P. nanus, minimal tempera- 

 ture for, 232 ; P. vulgaris, freezing- 

 point of, 242 ; influence of cold on, 

 233 ; resistance of, to heat, 231. 



Phellogen, influence of pressure on, 44. 



Phenols, removal of, 270. 



Philippi, 140. 



Phisalix, on asporogeny, 193. 



Phloem, grand period of growth of, 13. 



Phormium tenax, shape of leaves of, 54. 



Photoepinasty, 73. 



Photomorphic actions, 85. 



Photomorphosis, 2, 72, 137. 



Photonasty, 137 ; definition of, 73. 



Phototonus, 69 ; definition of, 85. 



Phy corny ces, correlation of growth in, 164 ; 

 influence of contact on, 129; light 

 on growth of, 96, Fig. 21 ; P. nitens, 

 freezing of, 241 ; growth-coefficient of, 

 17 ; growth of sporangiophore of, 10, 

 II, Fig. 4; influence of injury on 

 growth of, 135 ; inversion on growth 

 of, 1 10 ; non-germination of, on water, 

 113; resistance of, to desiccation, 

 251 ; vitality of spores of, 254. 



Pkyllocactus, influence of darkness on, 87 ; 

 light on apical growth of, 93. 



Phyllotaxis, causes of, 144, 145. 



Phytocecidia, 171. 



Pick, 151. 



Pictet, 237 ; on influence of low tempera- 

 tures, 234 ; of cold on bacteria, 238 ; 

 on toxins, 239. 



and Yung, 238, 239. 



Pigments, action of light on, 248. 



Piliferous layer, regeneration of, 169. 



Pilobulus, influence of darkness on growth 

 of, 164 ; non-formation of sporangia 

 under water, 121 ; P. crystallinus, 

 growth of sporangiophore of, 1 1 ; 

 influence of orange rays on, 104; P. 

 mtcrosporus, influence of light on 

 formation of sporangium of, 97 ; - 



PFEFFER. II 



on formation of sporophore of, 90; 

 P. torriduS) temperature for germina- 

 tion of, 81. 



Pilularia, germination of spores of, in 

 darkness, 92. 



Pinus, symmetry in tissues of, 48 ; P. syl- 

 vestriS) growth in thickness of, 13 ; 

 non-reproduction of, by cuttings, 168 ; 

 rapidity of growth of, 16; tempera- 

 ture limits for growth of, 76. 



Pisum, influence of light on hypocotyl 

 of, 87 ; P. sativum, influence of light 

 on growth of, 97 ; temperature on 

 growth of, 77. 



Pith, compression of, 61 ; elongation of, 66. 



Planchon, 117. 



Plasmatic membrane, influence of, on poi- 

 sonous action, 266. 



Plasmodia, influence of oxygen on, 117 ; 

 mechanical vibrations on, 131. 



Plasmolysis, influence of temperature on, 

 67 ; shortening produced by, 60. 



Plasmolytic solutions, vitality of cells in, 

 257. 



Plasmoptyse, 119. 



Plasticity of tissues, 58 ; influence of, on 

 curvature, 58, 59. 



Plectenchyma, 46. 



Pleurococcus, resistance of, to desiccation, 

 255. 



Poa annua,) influence of cold on, 236. 



Podostemonaceae, haptera of, 129. 



Poisonous actions, avoidance of, 263. 



Poisons, detailed action, 264 ; general pro- 

 perties of, 258 ; influence of chemical 

 constitution, 271 ; - - desiccation on 

 action of, 252 ; temperature on 

 action of, 228 ; mode of action of, 267 ; 

 non-assimilation of, 268; removal of, 

 269, 270. 



Polarity, induction of, 154; influence of, 

 on grafting, 176 ; influence of gravity 

 on, 156; light on, 157; of cells, 

 159; origin of, 160; of Salix, 155, 

 Fig. 26. 



Pollen-grains, action of salt on, 262 ; con- 

 dition for germination of, 114; extru- 

 sion of solid particles by, 1 19 ; growth 

 of coats of, 30 ; resistance of, to heat, 

 229 ; strains in wall of, 65 ; vitality of, 

 254. 



Pollen-tube, influence of, on fruit forma- 

 tion, 173 ; limited growth of, 145, 195 ; 

 penetration of, 45. 



Polygonum, intercalary growing zones in, 9 ; 

 strains in stem of, 61. 



Polypodium vulgare, resistance of, to desic- 

 cation, 254. 



Pclyporus^ influence of light on develop- 

 ment of, 94 ; resistance of, to cold, 

 238. 



Popovici, 12, Si. 



Populus, callus-formation in, 132 ; influence 



U 



