INDEX 
Water-net (see also ‘‘ Hydrodic- 
~ tyon), 43, 44, Fig. 7. 
Weeds, 240, 241, 243. 
Western America, 233, 238, 239. 
Western Asia, 233. 
Western Europe, 233, 
West Indies, 194. 
Wheat-rust (Puccinia graminis), 88, 
89, 95. 
White birch, 230. 
White rust (Cystopus candidus), 82, 
83, 84, 85, Fig. 21. 
Wild-oats (Avena fatua), 241. 
Willow, 206, 228, 229, 230, 244, Fig. 
49. 
Wind-pollination (see also “ Anem- 
ophily ’’), 244. 
Winter buds (of deciduous trees), 
270, 281, Fig. 59. 
Wood, woody tissue, 124, 267. 
x 
Xylem (see also ‘‘ Wood ’’), 124. 
Xerophytes, 201, 204, 271, 272, 273, 
274. 
319 
Y 
Yeast-fungus (Saccharomyces), 96. 
Yew (see also ‘‘ Taxus’’), 165, 168. 
Yucca, 191, 237, 257, 272. 
Zz 
Zamia, Z. integrifolia, 162, 163, Fig. 
40. 
Zauschneria, 249. 
Zingiber (see also ‘‘ Ginger ’’), 193. 
Zoology, 11. 
Zodspores(see also‘ Swarm-spores ”), 
44, 50, 51, 52, 53, 54, 57, 58, 69, 70, 
73, 78, 82, 83, 84, 86, 102, 104, 118, 
128, 266, 285, 286, 287. 
Zygomorphy, Zygomorphic flowers, 
189, 191, 193, 194, 195, 207, 209, 210, 
251, Figs. 46, 47, 50, 51, 56, 57. 
Zygospores (of Conjugate), 61, 86. 
Zygote (see also ‘“‘ Zygospores), 26, 
39, 
