622 



A. W. GRABAU TYPES OF SEDIMENTARY OVERLAP 



Feet 



11. Equus bed ±50 



10. Dark brown to black sandstone, forming prominent escarpments, very 



fossiliferous in a layer 1 to 2 feet thick in the middle of the ledge. 8 



The fossils are listed by Gould.* 



9. Soft yellow sandstone 2 



8. Hard massive gray and yellowish sandstone 4 



7. Yellowish and bluish shales 16 



6. Rather hard yellowish sandstone 8 



5. Bluish to yellowish paper shales, very like Kiowa, with selenite and 

 cone-in-cone gypsum ; contains layers of soft yellow sandstone with 



dicotyledonous leaves 40 



4. Two six-inch ledges of very fossiliferous limestone separated by 



shales 3 



The fossils are listed by Gould.t 

 3. Shales like the Kiowa, with iron pyrites, selenite, and cone-in-cone 



gypsum 20 



2. Gray to yellowish sandstone, with much lignite and crushed plant 



material in places ; very like Cheyenne 4 



Total Comanche-Dakota 105 



Disconformity. 

 1. Permian shales, red, blue, green, etc. 



The sandstone number 10 has all the appearance of the Dakota sand- 

 stone and lies 50 feet above the stratum in which the first disotyledonous 

 plant remains are found. Lithically this entire series belongs in the base 

 of the Dakota. Similiar conditions exist at Mentor, 20 miles northeast, 

 but the exposures are not so satisfactory. 



The fauna of both the lower and upper beds is that of the Kiowa shales. 

 In the typical section this comprises 125 to 150 feet of bluish gray paper 

 shale, becoming more arenaceous upward. Interspersed throughout the 

 formation are layers of hard gray limestone, soft sandstone, and pebbles. 

 Gypsum occurs throughout and the shales are fossiliferous. The fauna 

 as listed by CraginJ contains 51 species of intertebrates and 13 species 

 of vertebrates. 



The base of the Kiowa shales of Kansas is formed by the Champion 

 shell-bed, a thin stratum of shell conglomerate commonly less than a 

 foot in thickness and rarely more than a foot and a half. Gryphssa hilli 

 is the only fossil found in it in some localities, but elsewhere a consider- 

 able number of species have been found. Of 36 species listed by Cragin, 

 22 pass upward into the Kiowa shale, the remainder apparently not 

 occurring above the shell-bed. Among these latter is Gryplisea hilli, which 



* Ibid., p. 37. 



t Loc. cit, pp. 36, 37. 



\ American Geologist, vol. xvi, 1895, pp. 372, 373. 



