194 E. Bose — Permian of Coalmila, N. Mex. 



south, because south of the depression between Torreon 

 and Saltillo we find again the uninterrupted Jura- 

 Cretaceous series. The probable west and east limits of 

 this continent will be discussed at another time. 



I have tried to find the continuation of the Permian 

 farther north, and for this purpose have crossed the 

 desert between Cuatro Cienegas and Sierra Mojada, but 

 have failed to find it there, as everything is covered by 

 middle and upper Cretaceous. Of course, there is a 

 possibility that Paleozoic rocks may be exposed farther 

 north. 



With our conclusion that the Delicias beds and the 

 Pichagua limestone are of the same age, there arises the 

 question which of the two names should persist. I think 

 that it would be best to retain the name Delicias, not as 

 a denomination of a horizon but as that of a facies.- We 

 can not very well take the name of a small cliff of lime- 

 stone for this important series, but had better apply the 

 name of the hacienda in the territory of which lie all of 

 the beds described. 



Monterey, Nuevo Leon, Mexico, August, 1920. 



