230 E. B. BRANSON ORIGIN OF RED BIRDS OF AVESTERN WYOMING 



before, the contact of the Popo Agie beds with the under] vino- sandstones 

 is always covered and a disconformity may exist at that place. It is 

 possible that the Eed Beds below are Permian, and that the Upper 

 Triassic rests disconformably npon them. The Red Beds above tlie Popo 

 Agie beds arc surely Triassic in age for some tliickness, and probably to 

 the top, though there is no positive evidence tliat the upper ipari is not 

 Jurassic. The marine Upper Jurassic lies unconformably on the Red 

 Beds. 



