NORTH AMERICA AND THEIR VERTEBRATE FAUNA. 9 



it from top to bottom. The sandstones are of various colors. The clays are red 

 and bluish. In places the clay is copper-bearing, yet this is not entirely peculiar 

 to these beds, as the same thing occurs in the Clear Fork Beds. In the red clays 

 are iron concretions that exist in places in great abundance. The peculiar Permian 

 conglomerate which is found in this connection is composed of clay, or clay iron- 

 stone, in a ferruginous matrix." 



QUATERNARY 



PERM IAN 



Recent 

 deposits 



Seymour 

 gravel 



: 



Undifferentiated 

 Clear Fork and 

 Double Mountain 



PENNSYLVA,NIAN 



V'^^v/. 



Cisco 

 formation 



Ca nyon 

 I imeatone 



Strawn 

 formation 



Fig. I. — Map showing Gordon's idea of the distribution of the Wichita, Clear Fork, and Double 

 Mountain formations in Te.xas. (After Gordon.) 



Gordon,* in 191 1, gave an account of the same beds. He regards the 

 Wichita as extending much farther to the west than does Cummins or the 

 author, and includes much that was previously described as Clear Fork. 

 In discussing the Red Beds of Texas cast of a line drawn southwest from 

 near the mouth of the Pease River through Seymour to the northeastern 



° Gordon, Jour. Geol., vol. xi.\, p. no, 191 1. 



