STRATIGRAPHIC SUMMARY. 643 



probably corresponding to Kanawhan. According to the testimony 

 of the plants the Grady coal is near the horizon of the Mason 

 Creek beds (Morris coal), probably of Kittanning age, while the 

 McAlester is nearer the Freeport horizon. In Arkansas, the Mc- 

 Alester shale is divided into three parts, the upper or Paris with 

 the Paris coal (upper Kittanning) about 400 ft. below the top, a 

 middle or Fort Smith with the Coal Ridge or Charleston coal 

 (middle Kittanning) part way below the top, and a lower or 

 Spadra, with the Hartshorn (lower Kittanning) coal at the base. 

 The Hartshorn sandstone appears to be non-marine, while the 

 Atoka contains scattered marine fossils in the upper part above the 

 Atoka coal (Kanawha). The upper Atoka in the north is known 

 as the Winslow shale. The Coal Hill or Upper Atoka beds corre- 

 spond according to the evidence of the plants, to the Cherokee 

 shales of Kansas, which there rest disconformably on late 

 Mississippic. 



The Kansas section includes the following divisions (according 

 to Prosser and Haworth) : 



SUPERFORMATION. 



Mesozoic or later. 



{D is conformity and hiatus.) 



' Cimarron stage. 



-r^ . vSumner stage. 



Permic J ^„ 



" Chase stage. 



Council Grove stage. 



-Wabaunsee stage. 



Shawnee stage. 



Douglas stage. 



Pottawatome stage. 



Marmaton stage. 



Cherokee stage. 



{D is conformity and hiatus.) 



SUBFORMATION. 



Mississippic beds. 



The Sumner and Chase have been united by Cragin as the Big 

 Blue Series, for which Keyes later proposed the term Oklahoman. 



Carbonic. 



