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. 



