592 RALPH W. CHANEY , 
CONCLUSION 
Plants may, then, with a degree of caution, be used, not only to 
show the character of past climate, but they may also be called 
upon to indicate the length of time involved in a given epoch, and 
the general character of the topography. 
In the case of the Eagle Creek flora the climate appears to 
have been somewhat warmer and drier than at present. The. 
length of the epoch is to be placed at thousands rather than at 
scores of years. The evidence of the dominant species of plants 
points to the probable existence of a twofold habitat, one xerophytic 
and the other mesophytic. An upland cut by valley-like depres- 
sions furnishes the conditions which are thus required by the plants 
and at the same time fits in equally well with the strictly geological 
characteristics of the Eagle Creek formation. 
