6 THE PERMO-CARBONIFEROUS RED BEDS OF 



in Oldham County, Texas, and again in Beaver County, Oklahoma. From 

 here it appears at intervals from beneath the Tertiary, curving through 

 Clark, Comanche, Barber, Kingman, and Harper Counties, Kansas. 



STRATIGRAPHY OF THE BEDS IN TEXAS. 



The Permo- Carboniferous beds of Texas were divided by Cummins * 

 into three formations: the Double Mountain, the Clear Fork, and the 

 Wichita. Schuchert'' vmites these in the Brazos group, which is equivalent 

 to the Oklahoman of Keyes. These beds can be directly correlated with 

 certain beds in Oklahoma, as shown by the following from Gould :^ 



"From the best available information, it seems probable that the Wichita 

 beds are approximately the equivalent of those near Chandler, the Clear Fork 

 beds include about the same rocks as the Enid, Blaine, and Woodward formations, 

 and that the Double Mountain beds are practically the same as the Greer and the 

 Quartermaster formations." 



With the ideas expressed by Gould in this quotation, the author is in 

 perfect accord, as the result of his work during several ycai-s in Texas and 

 Oklahoma, and especially from his study of the formations mentioned 

 during the summer of 191 2. 



The Wichita and Clear Fork in Texas and the Enid in Oklahoma are 

 the only formations in which vertebrate fossils have been found. The 

 Wichita formation lies in an area between the east line described above 

 and a line running from the Red River southwest just east of HoUiday, 

 in Archer County, and south to the northwest corner of Young County, 

 where it crosses the west line and apparently continues a little west of south 

 to where it joins the edge of the Carboniferous. The line between the 

 Wichita and the Clear Fork is very difficult to determine at this point 

 (plate i). The western limit of the Clear Fork formation follows a line 

 approximately through or slightly west of Haskell, north to Seymoirr in 

 Baylor County, and north to the Red River, which it strikes just east of 

 the west line of Wilbarger County. This line is close to the one originally 

 drawn by Cummins.'^ The Double Mountain formation includes the western 

 portion of the Red Beds in Texas, between the western edge of the Clear 

 Fork and the eastern face of the Llano Estacado. 



If, as believed by Gould and the author, the Enid, Blaine, and Woodward 

 formations in Oklahoma are the equivalent of the Clear Fork, the western 

 limit of the possible bone-bearing beds in that State runs northwest through 

 Caddo, Washita, Custer, Dewey, Woodward, and Harper Counties to the 

 Kansas line, as indicated in Gould's map.^ To this must be added, in the 

 opinion of the author, all the region marked by Gould as "Red Beds of 



° Cummins, First Annual Report Geological Sur^'ey of Texas, 1889, p. 186. 



*> Schuchert, Paleogeography of North America, Bull. Am. Geol. Soc, vol. 20, p. 558. 



" Gould, U. S. Geological Survey, Water Supply and Irrigation Paper No. 154, p. 17. 



•^ Cummins, 2d Annual Report, Geol. Sun'. Texas, map opposite p. 522. 



'Gould, U. S. Geological Survey, Water Supply and Irrigation Paper No. 148. 



