682 
Wolffia rae, colum- 
biana, 13 
Wyoming, hae plants from, 239 
134, 138, 
Xanthidium amet 163, armatum, 
583, hastiferu 163, hastiferum 
eine longis spinum, 163, hasti- 
m Tow 
Sa a aia 
rium, 15 
156, 157, struma- 
INDEX 
Xanthochrous, 341, 599, tomentosus, 346 | 
oc ie aaa aplifolia, 16 
44 
Xylar 
Xylo ae anguineum, 421 | 
Xylopilus, vires crassus, 424 | 
zea 
Mays, 59 
Zizania aquatica, 446, 138 
