INDEX 



459 



Thesium, 215, 388 



TMIRIAZEFF on relative values of 

 the rays of the spectrum in photo- 

 synthesis, 171 



Tone, 359, 364, 367 



Torsion of stems, 388 



Tradescantia, 7, 351 



Translocation, of food, 223 ; direc- 

 tion of, 230 ; path of, 233, 234 



Transpiration, 75, 81, 88 ; methods 

 of demonstrating, 88 ; amount 

 of, 91 ; effect of excessive, 91 ; 

 influence of external conditions 

 on, 95 ; suction of, 100 ; functions 

 of, 324, 325 ; relation to etiola- 

 tion, 368 



Transpiration current, 78, 80 



Trees, conditions of life of, 24 



Trehalase, 264 



TREUB on construction of proteid 

 in Pangium, 181 



Trichogyne, 424 



Tropceolacece, 260 



Tropczolum, 83, 167 



Trypsin, 262, 265, 266 



Turgescence, 61 ; importance of, 

 64; methods of restoring, in 

 flaccid tissue, 91 ; affected by 

 shaking branches, 97 



Turgor, 351 ; also see Turgescence 



Twigs, reserve materials in, 241 



Twining organs, 386 



Typha, 27, 29 



Tyrosin, 180 



Tyrosinase, 300 



Ulothrix, 1, 411, 418, 421, 422 

 UNGER on relative volumes of air 

 and cellular tissue in leaves, 113 

 Unicellular plants, 2 

 Urea, 149 

 Urease, 269 

 Utricularia, 199 



Vacuole, 4 ; formation of, 13, 56 ; 

 function of, 14 ; occasional ab- 

 sence of, 54 ; pulsating, 348, 352 



Vallisneria, 6, 351 



Vascular bundles, 22, 27 



Vauclwria, 421 



Vegetable acids, 284 



Vegetative propagation, 417 



Veins of leaf, 22, 72 



Velamen, 340 



Venus' s fly-trap, see Dioncea 



Vicia, 400 



Victoria regia, 333 



VINES on photosynthesis, 168 



Viola, 442 



Vitis, 87 



Volvox, 9, 10 



Water, importance of, to proto- 

 plasm 13, 14, to plant in general 

 14 ; absorption of, by aquatic 

 plants, 22 ; function of, in cell, 

 54 ; circulation of, in plant, 54 ; 

 exhalation of vapour of, 60, 125 ; 

 hygroscopic, 68; absorption by 

 root-hairs, 69 ; transport in root 

 70, in stem 72 ; excretion of, 76 ; 

 mode of transport in wood, 79 ; 

 exudation of, under pressure, 83 ; 

 exudation affected by salts, 86 



Water-culture, 140, 185 



Water-glands, 337 



Wax in cell-walls, 50 



WIESNEB, on composition of cell- 

 wall, 44 ; on heliotropism, 398 



Withering, 91 



Wood, 22 



Xanthophyll, 157, 285 

 Xerophytes, 336 



Yeast, 2, 302, 412, 420 



Zein, 177 

 Zinc, 143, 188 

 Zirconium, 188 

 Zoocoenocyte, 421 

 Zoogonidia, 419 

 Zoophilous flowers, 438 

 Zoospores, 1, 419 

 Zygnema, 159, 422 

 Zygospore, 422, 425 

 Zygote, 425 

 Zymase, 269 

 Zymogen, 259 



Square, London. 



