INDEX. 



Witches' broods (fir-t ees), 



128. 

 Woodwardia, roots and 



shoots from leaves, 213. 

 Wrangelieae, 78. 



Xylaria, perithecium, 108 ; 



stroma, 109. 

 Xylem, 309. 

 Xyridieae, 444. 



Yeast-fungus, 81, 113; nu- 

 cleus, 1 1 3, note 4 ; pullu- 

 lation, 81. 



Yucca, 444 ; exine, 367 ; 

 growth in thickness, 443. 



Zamia, carpels, 317; coty- 

 ledons, 318; flowers, 315; 

 leaves, 313 ; microspores, 

 316 ; stem, 344. 



Zamia muricata, flowers. 



314; microsporangia, 316. 



(Fig. 247.) 

 Zamia spiralis, staminal leaf, 



315. (Fig. 249.) 

 Zanardinia, 69. 

 Zannichellia, embryo, 430 ; 



ovule, 385. 

 Zea, plumule and stem, 432 ; 



pollination, 390 ; primary 



root, 431 ; primary stem, 



432 ; synergidae, 389 ; 



vascular bundles, 442. 



(Fig- 355-) 

 Zea Mais, 86, 431. (Fig. 



355.) 

 Zingiberaceae, staminodes, 



440. 

 Zingibereae, 444, 445. (Fig. 



368.) 



Zoogametes, 5. 

 Zoogloea-forms, 24. 

 Zoogonidia, n, 84. 



Zoogonidia-receptacles, n. 

 Zoosporangia, 31, 43, 96, 



125. 



Zoospores, 42. 

 Zostera, pollen-grains, 369. 

 Zygnema, 50. 



Zygnema cruciatum, Fig. 26. 

 Zygnemeae, 49 ; relation to 



Desmidieae, 50. 

 Zygogonium, 50. 

 Zygomorphous, 423. 

 Zygomycetes, 40, 88 ; re- 

 production, 88, 89. 

 Zygophylleae, 469 ; floral 



diagram, 41 9 ; flower, 



423. 

 Zygospore, 19, 31, 35, 40, 



4 2 > 49, 50, 5 1 . 8 3, 89, 90, 



91. 

 Zygospores, conjugation and 



formation, 5. (Fig. i.) 

 Zygozoospores, 40, 41. 



THE END. 



