5 6 4 



INDEX 



of, by conduction, 398 ; by radiation, 398 ; 

 by transpiration, 44, 398. 



Tendrils, reacting all round, 490; senile 

 curvature in, 495 ; autotropism in, 493 ; 

 reacting unilaterally, 489 ; distribution 

 of sensitivity in, 490 ; curvature in, on 

 stimulation, 499 ; circumnutation in, 489, 

 530 ; perception in, 490, 491 ; stimula- 

 tion of both sides of, 490 ; due to chemical 

 influences, 492 ; due to electricity, 492 ; 

 due to contact, 491 ; due to temperature, 

 492 ; tropistic curvature in, 490 ; clasp- 

 ing of supports by, 495 ; distribution of 

 growth in, 488 ; nastic curvature in, 499. 



Tension, influence of on growth, 261. 



Tetrathionic acid, 229. 



Thermonastic, 499, 500, 502. 



Thermotaxis, 548. 



Thigmotaxis, 548. 



Thiosulphate, 229. 



Thiothrix, 223. 



Thyloses, 296. 



Tissue tensions, 297, 421. 



Tonotaxis, see Osmotaxis. 



Torsion, 406 ; autonomous, 531 ; geotropic, 

 452, 453 ; heliotropic, 465 ; due to shrivel- 

 ling, 414. 



Tracheae and tracheides, see Vessels. 



Transitory nutation, 530. 



Translocation products, 148, 172; of 

 materials : from the leaf, 1 66 ; from store- 

 houses of reserves, 167; from seeds, 155, 

 168. 



Transpiration, 25, 35 ; dependence of, on 

 external conditions, 38 ; on stomata, 39 ; 

 on the structure of the plant, 37 ; in- 

 fluence of, on absorption of nutrients, 43 ; 

 on the temperature of the plant, 43 ; on 

 ascent of water, 74 ; acceleration of, 43 ; 

 formative results of, 317 ; amount of, 43 ; 

 significance of, 43 ; inhibition of, 42 ; in- 

 ternal, 37 ; cuticular, 38 ; stomatal, 38. 



Transplantation, 332. 



Traumatotaxis, 553. 



Traumatotropism, 486. 



Trees, annual periodicity in, 344 ; winter 

 transformation of starch into fat in, 



175- 



Tropism, 428, 499. 



Turgor, 13, 263, 418. 



Twining plants, 455 ; geotropism in, 457 ; 

 spiral movements of, 456; supports to, 

 458 ; torsions in, 458 ; twining of, 455. 



Twinings, 406 ; autonomous, 530 ; in ten- 

 drils, see Tendrils ; due to shrivelling, 

 412 ; in twining plants, 457. 



Tyrosin, 140, 174, 444. 



Undulatory nutation, 531. 



Unicellular, 272. 



Urea, as a nutrient, 143, 144 ; fermentation 



of, 224. 



Uro-Bacteria, 224. 

 Urticaceae, stimulus movements in, 425. 



Vacuoles, 6. 



Variation, see Adaptation, Species, Muta- 

 tion ; fluctuating, 387 ; movements, 421 ; 

 autonomous, 528 ; geotropic, 453 ; helio- 

 tropic, 465 ; paratonic, 428. 



Vegetative growing point, 272 ; basal, 273 ; 

 structure of, 279-81 ; form of, 276 ; in- 

 tercalary, 273, 292 ; of the stem, 277 ; 

 symmetry of, 274, 276 ; capacity of, 273 ; 

 terminal, 273 ; growth in, 280 ; distri- 

 bution of, 284 ; of the root, 283 ; arrange- 

 ment of cells in, 279. 



Ventral, side, 276. 



Vessels, structure of, 66-70 ; functions of, 

 47, 172 ; contents of, 70 ; absorption of 

 water by, 49. 



Volume, alteration in, in growth, 258. 



Water, excretion of, see Bleeding, Tran- 

 spiration ; absorption of, by aerial 1 organs, 

 32 ; by roots, 29 ; by cells, 24 ; influence 

 of different factors on, 31 ; excretion of, by 

 hydathodes, 58 ; significance of, in move- 

 ment, 539; movement of, in the plant, 

 45-7 ; influence of, in germination, 252 ; 

 in growth, 317; withdrawal of, 318; 

 conduction of, 25 ; influence of living 

 cells on, 74-6 ; through vessels, 47 ; by 

 capillarity, 72; rate of, 62 ; height of, 62 ; 

 amount of, 61 ; by parenchyma, 46 ; di- 

 rection of, 6 1 ; by suction, 64 ; in dead 

 trees, 75 ; by root pressure, 63 ; glands, 

 58 ; amount of in soil, 26, 318 ; in air, 

 318; capacity, 26; culture, 80; plants, 

 absorption by, 24 ; cause of form, 319. 



Wax, 4. 



Whorl, 274. 



Working energy, 205, 403, 404. 



Working materials, 148. 



Wounds, healing of, 328 ; regeneration 

 from, 329 ; as stimuli to protoplasmic 

 movement, 540 ; as directive stimuli, 

 486, 553- 



Xerophytes, adaptation in, 253. 



Zinc, 87. 



Zone of maximal growth, 289. 



Zymase, 211. 



Oxford : Printed at the Clarendon Press by HORACE HART, M.A. 



