94 THE PERMO-CARBONIFEROUS RED BEDS OF 



Wreford limestone, Kansas (Beede " in a recent paper draws it at the base of 

 the Neva limestone); Enid, Oklahoma; Wichita, Texas; Manzano (?), New 

 Mexico; Moencopie and Kanab (Aubrey), Arizona; Cutler and Lykins, Colo- 

 rado; Upper Weber, Utah; Upper Embar and Opechee, Wyoming; Opechee, 

 South Dakota ; Merom sandstone, Indiana ; Ames limestone, Pennsylvania. 

 The charts opposite pages 64 and 66 (plates 2 and 3) from Darton show the 

 relations of most of the Red Beds in the northern part of the Plains Province. 



The lower limit of the fauna is confessedly vague and shadowy, passing 

 far down into the Pennsylvanian. The Pennsylvanian amphibians described 

 by Moodie in numerous papers are so close to those occurring in association 

 with the Permo-Carboniferous forms from Texas that it is evidently a case 

 of overlapping, and the only recognizable line is that where the first reptile 

 occurs. It is, of course, probable that the reptiles occurred at lower horizons. 

 In 19 10 Moodie found a form near Cricotus in the Mazon Creek shales.*" 

 These shales are near the base of the Allegheny (or even the top of Pottsville). 

 David White regards them as equivalents of Coal No. 2 of Illinois (Morris and 

 Braidwood coals of the Clarion). They are all regarded by him as having 

 close relationship with the Cherokee of Henry County, Missouri, at the base 

 of the Allegheny." 



The Linton coal, from which comes Eosauravus copei Williston {Isodectes 

 panctulatus, originally Tiiditanus piinctalatas, Cope), belongs in the Upper 

 Freeport coal (Coal No. 6), and is referred by Prosser "^ to a position near the 

 top of the Allegheny. The old coal mine (Diamond coal mine) located near 

 Linton, Jefferson County, Ohio, from which numerous amphibians and a few 

 reptiles have been collected, has been abandoned, and further collections 

 are impossible. Williston " and Moodie ^ have described the genus Eosaur- 

 avus, giving figures, and demonstrated its reptilian nature. 



The earliest amphibians definitely comparable to the Texas fauna are 

 those from the Pittsburgh red shale of Pennsylvania. The Pittsburgh red 

 shale lies 300 feet above the Freeport and 695 or more feet below the base 

 of the Dunkard. Dr. I. C. White ^ has remarked upon the significance of a 

 red formation above the limestone, in describing the dividing-line between 

 the Conemaugh and the Allegheny, which has been placed at the Upper 

 Freeport coal. He says: 



' ' Viewed from the standpoint of physical conditions, the proper place for such 

 a dividing plane between the Conemaugh and the Allegheny beds would be the first 

 appearance of red rocks near the horizon of the Bakerstown coal, about 100 feet 

 under the Ames or crinoidal limestone horizon. That a great physical change took 

 place soon after the deposition of the Mahoning sandstone rock, the present basal 



"Beede, Oklahoma Geol. Surv., Bull. 21, 1914. 



>> Moodie, So., vol. 30, 1910, p. 233. 



'White, Bull. 211, U. S. Geological Survey, p. in. 



'^ Prosser, Jour. Geol., vol. xi, p. 519 et seq. 



" Williston, Jour. Geol., vol. xvi. No. 5, 1908, pp. 395-400. 



' Moodie, Proc. U. S. Nat. Mus., vol. 37, p. 11, 1909. 



e White, West Virginia Geol. Survey, vol. 11, p. 226, 1903. 



