72 2 CHARLES S. PROSSER 



Vertebrate fossils found in northern Texas led Professor E. 

 D. Cope to the conclusion that the rocks were of Permian age 

 and he stated that "The evidence now adduced is sufficient to 

 assign the formation, as represented in Illinois and Texas, to the 

 Permian." 1 The invertebrate fossils from the same beds were 

 regarded by Dr. Charles A. White as indicating their Permian 

 age. 2 The stratigraphy of the Upper Paleozoic formations 

 of Texas was fully described by Professor W. F. Cummins, who 

 referred them to the Permian. 3 



In recent years the following geologists have studied the 

 Upper Paleozoic rocks of Oklahoma, Kansas or Nebraska and 

 termed them Permian. Dr. James P. Smith who stated that 

 "The lower Permo-Carboniferous strata of Kansas and Nebraska 

 are probably also to be correlated with the Artinsk stage [basal 

 Permian of Russia]." 4 Professor Cragin, who gave an extended 

 account of "the Permian system in Kansas;" 5 Professor Wilbur 

 C. Knight who wrote a similar paper on " The Nebraska Per- 

 mian " 6 and showed from tables of distribution that "Of the 

 forty-four genera of invertebrates known in the Kansas and 

 Nebraska rocks, over three-fourths of them belong to the Per- 

 mian of the Orient. The remainder are nearly all American 

 genera and are chiefly pelecypods." 7 Prof. Knight has also 

 stated that "From our present knowledge it seems advisable to 

 refer the Red Beds of the Laramie Plains [Wyoming] to the 

 Permian." 8 Dr. J. W. Beede, in his paper on "A Reconnaissance 

 in the Blue Valley Permian " 9 described the Lower Permian as 

 represented in Kansas north of the Kansas river and in southern 

 Nebraska. And finally Professor Charles N. Gould and Doctor 



1 Geo/. Surv. Texas, Second Ann. Rept., 1891, p. 414. 



2 Bull. U. S. Geol. Surv., No. 77, 1891. 



3 Geol. Surv. Texas, Fourth Ann. Rept., 1893, p. 212. 



4 Jour. Geol., Vol, II, 1894, p. 194; and see pp. 188, 204. Also see Proc. Am. 

 Phil. Soc., Vol. XXXV, 1896, reprint pp. n, 12, 24. 



5 Col. Coll. Studies, Vol. VI, 1896, pp. 1-49 and supplemented by one in the Am. 

 Geol.. Vol. XIX, 1897, pp. 351-64. 



6 Jour. Geol., Vol. VII, 1899, pp. 357-75. 



7 Ibid., p. 370. 8 Jour. Geol., Vol. X, 1902, p. 421. 



9 Ran. Univ. Quart., Vol. IX, July, 1900 (1901), pp. 191-203. 



