DIFFERENT ALTITUDES IN COLORADO 51 
and greater rainfall there. A brief statement is made of differ- 
ences in the grasslands not at once apparent from the systematic 
list. Floristically the dry grasslands of the mountain front and 
of the subalpine zone are almost totally different, but considerable 
similarily exists between those of the mountain front and of the 
montane zone. 
UNIVERSITY OF COLORADO, 
OULDER, COLORADO. 
LITERATURE CITED 
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5 ath 
Nichols, George E. The interpretation and application of certain 
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PO fe HE nS 
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