442 



INDEX 



Perception, definition of, 5 ; localization of, 

 192 ; of stimuli, 219; and response, 

 relation between, 8. 



Periblem, traumatropism of, 186. 



Peridinium tab^^latum, galvanotaxis of, 361. 



Periodicity, in heat-production, 372, 376, 

 377 ; photonastic origin of, 108. 



Periploca graeca, twining of, 38. 



Permeability, influence of, on osmotropism, 

 230. 



Peronospora, hygroscopic torsion of, 151. 



Pertz, 26, no, 124, 166, 190,210, 218, 418. 



Petiole, curvature of, 232. 



Petiole-climbers, 43, 44, 45. 



Peztza fuckeliana, heliotropism of, 173. 



Pfeffer, I, 2, 3, 13, 14, 17, 18, 24, 25, 26,30, 

 31, 47, 48, 73, 74, 76, 81, 85, 89, 91,92, 

 93, 102, 104, 105, 106, 118, 119, 145, 

 154, 211, 220, 223, 233, 236, 237, 238, 

 239, 240, 263, 265, 266, 267, 268, 269, 

 270, 275, 276, 286, 292, 303, 325, 343, 

 358, 362,368,400; on changes of tone, 

 208; on chemotaxis, 180, 311, 312, 

 344, 345, 346, 347, 348, 350, 351, 352, 

 353, 354, 357 J on chemot.ropism, 230, 

 231 ; .on coiling of Phycomyces, 37; on 

 conjoint excitation, 216 ; on consis- 

 tency of protoplasm, 279, 280 ; on con- 

 tact - irritability, 83 ; on contractile 

 mechanism, 78, 79, 80 ; on daily move- 

 ments of plants, 119-26 ; on daily 

 periodicity, 1 12 ; on density of particles 

 in the cell, 334 ; on depression of ex- 

 citability, 69 ; on excitability of pulvini 

 of Oxalis, 70 ; on expansive energy in 

 pulvinus, 32 ; on influence of anaes- 

 thetics on irritability, 94 ; on irritability 

 tADrosera, 84 ; on localization of sensa- 

 tion, 193, 198 ; on mechanism of move- 

 ment, 72 ; pulvinar, 75, 77, 79 ; 

 variation and nutation, 129, 131, 132, 

 133, 135-9 > influence of light and 

 temperature on, 141, 142 ; on motility, 

 35, 37, 39 J on movements of 

 Cynareae, 16; on nature of irritability, 

 1 1 ; on orientation of chloroplastids, 

 327 ; on pits in tendrils, 65 ; on pro- 

 duction of heat, 377, 379 ; on pulsating 

 vacuoles, 294-7 ; on sleep-movements, 

 103, 108-11 ; thermonastic, 113-16 ; 

 on transformations of energy, 401, 403, 

 406, 407, 408, 411, 412, 413 ; on tropic 

 responses, 241-8 ; on a klinostat, 

 161, 166, 169, 171, 174; on Weber's 

 Law, 213, 214, 215. 



Pfitzer, 148, 272. 



Pfltiger, 382, 384, 387. 



Phalaris, influence of darkness on nutation 

 of, 30 ; time of reaction of, 211. 



Phaseolus, 257, 258,417,419; changes of 

 turgor and rigidity in pulvinus of, 135, 

 238 ; climbing-hairs of, 40 ; curvature 

 of young pulvinus of, 245 ; direction of 



twining of, 38 ; limiting angle for, 

 40 ; insensitiveness to contact of, 35 ; 

 photonastic movements of, 105 ; time 

 of reaction of, 212 ; twining of, in dark- 

 ness, 30; P. multiflorus, influence of 

 gravity on sleep-movements of, 125, 

 Fig. 33, 126; loss of twining by, 38 ; 

 /*. vulgariS) energy of expansion in 

 pulvinus of, 136, 137,138 ; pulvinus of, 

 13, Fig. I ; rate of revolution in, 21 ;. 

 sleep-movements of, 104 ; influence 

 of gravity on , 125 ; variation move- 

 ments of, 22. 



Philadelphus, 259 ; changes of tone in, 

 205 ; epinasty of, 254 ; torsion of, 260. 



Phloroglucin reaction, 415. 



Phobism, 307, 309, 310 ; accumulation due 

 to, 311. 



Phobophototaxis, 215. 



Phoenix, geotropism of cotyledon of, 165. 



Pholas dactylus, 383, 387. 



Phosphates, chemotropic and chemotactic 

 action of, 181, 420, 421. 



Phosphorescence, 421. 



Phosphoric acid, influence of, on streaming, 



3i9- 



Photobacterium indicum, 385, 386; P. 

 luminosum, 386 ; P. phosphorescent? 

 385, 386. 



Photocleistogamy, 100, 106. 



Photokinesis, definition of, 6. 



Photometric leaves, 260, 261. 



Photometry, definition of, 3. 



Photonasty, 97 ; instances of, 101 ; uses of,. 

 100 ; in pulvini, 14. 



Photosynthesis, influence of, on movements 

 of chloroplastids, 332 ; on produc- 

 tion of electricity, 396. 



Phototaxis, 321, 419; changes of, 32 1,323 ; 

 character of, 322; of Diatoms and 

 Desmids, 325 ; of Myxomycetes, 326 ; 

 of zoospores, 324. 



Phototonus, influence of, on autonomic 

 movement, 30 ; of different rays on, 

 142 ; of external agencies on, 319. 



Phototropism, nature of, 227. 



Phycomyces^ 92, 177, 182, 187, 188 ; auto- 

 nomic movements of, 19 ; autotropism 

 of, 189 ; contact-irritability of, 83 \ 

 discriminatory sense of, 213; hydro- 

 tropism of, 183 ; influence of anaes- 

 thetics on geotropism of, 145 ; irrita- 

 bility of, on a klinostat, 48 ; localized 

 perception in, 195 ; parallelotropism of, 

 156; rheotropism of, 185; time of 

 heliotropic induction in, 211 ; P. 

 nitens, coiling of, 37, 46, 82 ; geotropism 

 of, 165 ; heliotropism of, 171, 173. 



Phyllanthus Niruri, sleep-movements of r 

 102, 104. 



Piccard, 418, 419. 



Picea, 260 ; P. excelsa, changes of tone in, 

 204. 



