POST-CRETACEOUS HISTORY OF WESTERN WYOMING 325 



moraines, and even those lakes which He in the courses of the main 

 creeks have been only slightly reduced by the building of deltas 

 or the cutting of outlets. 



Bull Lake stage: The next older moraines, which I have com- 

 pared with the early Wisconsin drift of Illinois, will be called the 

 Bull Lake drift, from the locality of that name on the north slope 

 of the Wind River Range. The deposits of this stage are definitely 

 related to the terraces of the Circle erosion cycle in that they blend 



Fig. 42. — Hills in the latest terminal moraine at the lower end of Bull Lake, 

 prominence of bowlders is characteristic. 



The 



into the gravel-strewn benches as modern moraines blend into their 

 outwash deposits. The moraines are still largely intact, and by 

 using a little imagination to supply gaps, they can be mapped in 

 their original extent. In protected places, as on flat uplands, the 

 topography is still visibly morainic, consisting of orderless humps 

 and hollows. That the Bull Lake drift is nevertheless distinctly 

 older than the Pinedale drift seems to me to be indicated by the 

 following facts : {a) bowlders are by no means as abundant upon the 



