INDEX 



365 



Tree group, 282. 

 Tropical forest, 355. 

 Truffle, 147. 



Tuber, 65; self-burial, 67. 

 Tumbleweed, 257. 

 Turgor, 104. 

 Turpentine, 219. 

 Twiner, 47. 



Ulothrix, 105. 

 Umbel, 233. 

 UmbellifenB, 294. 



Vacuole, 115. 



Variation, 316. 



Vascular bundle, 51. 



Va-ruUir cylinder, 50, 74. 



Vascular system, 76; fern, 188. 



Vaurheria, 111. 



Vegetative multiplication, 101. 



Vegetative propagation, 316. 



Vein, IS, 53. 



Venation, 6. 



Venus fly-trap, 40. 



Vernal habit, 67. 



Viticulture, 298. 



Water, absorption by root, 78; 



absorption by seed, 86; plant 



associations, 324. 

 Watermelon, 314. 

 Water plants, 326. 

 Water reservoirs, in plants, 29; 



pollution of, 102. 

 Water-root, 80. 

 Water-sprout, 70. 

 Wheat, 264. 

 Wheat rust, 149. 

 White pine, timber, 218. 

 Wind, plant associations, 326. 

 Wings, 291. 

 Winter spore, 150. 

 Wood, 51; root, 74. 

 Wounds, healing, 55. 

 Wrack, 118. 



Xerophytes, 326, 337. 

 Xylem, 51; root, 74. 



Yeast, 138. 



Yellow pine, timber, 218. 



Yucca, pollination, 244. 



Zygospore, 107. 



(9, 



