718 C. R. KEYES TOYALANE AND LUCERO 



country by the winds so strikingly presented. Few places there are on 

 this continent where stream action as a general erosional power is so 

 manifestly utterly impotent. 



In the existence of plateau plains in the desert at many different levels 

 throughout the broad belts of the less resistant rocks there appears to be- 

 furnished one of the strongest proofs of the eolic character of the re- 

 gional erosive activities, since in situations of this kind not only are rain- 

 fall and water action very deficient and wholly inadequate to produce the 

 relief effects presented without the time element be vastly and unreason- 

 ably prolonged, but conditions are such in many cases as absolutely to 

 preclude the intervention of stream work. 



