PLEISTOCENE HISTORY OF SAN JUAN MOUNTAINS 409 
On the other hand, certain outlying bowlder deposits, recognized 
in the Uinta mountains by the senior author and in the Bighorn 
and Sawatch ranges by other observers, which there suggested a 
third and earlier glacial epoch, would appear to correspond closely 
to the deposits made by the ice of the San Juan epoch. Like the 
drift of that stage, as recognized in the San Juans, the bowlder- 
gravels noted in these ranges occur in patches at some distance 
from the mountain front and situated on or near divides. It is 
probable, then, that drift of the San Juan glacial epoch will be 
recognized in other ranges of the western Cordillera, and it is hoped 
that additional data may be secured bearing on the amount of 
Pleistocene and post-Pleistocene erosion in this portion of North 
America. 
