Wyoming, 22, 84 Zonation, 17, 19 



^ . „, ,^, altitudinal, 17, 18, 19, 187 



Xeric, 81, 161 u • * i i oo 



^ , ., , .- horizontal, 182 



Xerophilous, 146 ^ _„ ,„_ 



V . ,, r^c Zone, 73, 187 



Xerophyte 11,95 transitional, 172 



Xerosere, 152 -^ , /t- i n , , 



^ostera (Lelgrass), 1 1 



Yielding capacity, 32 ^gophyllum apiculatum (Caltrop), 36 



218 • Indlex 



