5 5 4 THE JO URN A L OFGEOLOG Y. 



bamiensis Lea., Levifnsiistrabeatoid.es Har., Pseudoliva vetusta Con., 

 CalyptropJiorous velatus Con. 



The flora of this sub-stage is quite varied, and some of the 

 forms very well preserved, but up to the present no study of it 

 has been made. 



Frio clays. — The Fayette subdivision passes upward into a 

 series of gypseous clays with sand and sandrock, differing greatly 

 lithologically from the underlying beds. This subdivision is 

 therefore proposed for them. According to Kennedy, they are 

 not present (in this form at least) on the Neches river, but I 

 found them well developed on the Frio and Nueces. 



The clays are dark colored, greenish gray, red or blue, usually 

 massive, with quantities of gypsum and with calcareous concre- 

 tions arranged in lines, giving them a stratified appearance. 

 The sandy clays are laminated and bedded, green, red or blue 

 in color, and interbedded with brown and green sandstone, which 

 is concretionary and, in places, highly indurated. Brown sands 

 overlie these, and are followed by laminated chocolate clays 

 containing concretions of crystalline limestone with manganese 

 dendritions. These clays weather white, as at the mouth of the 

 Frio. 



Typical exposures : Between Weedy creek and Oakville on 

 Atascosa and Frio rivers, and on the Nueces south of Tilden. 



While the fossils are not very abundant, enough were 

 found to determine its close relationship with the underlying 

 beds. The Ostrea, Corbula, etc., are distintly lower Claiborne 

 forms. 



So far as our observations go, this is the highest bed refer- 

 able to the Eocene and from the evidence now before us it 

 appears that there are no deposits in the State belonging 

 either to the Upper Claiborne, Vicksburg, or Jackson, since no 

 fossils characteristic of either of these stages have yet been 

 found. 



The Texas Eocene, as a whole, is therefore composed of a 

 series of comparatively shallow water deposits, laid down during 

 a period of slow and gentle oscillations. Numerous local uncon- 



