1 54 The American Geologist. September, 1905 
This certainly indicates a marked change in the opinions 
of American geologists concerning the age of these deposits 
since the publication of the writer's paper on "The Classifi- 
cation of the Upper Paleozoic rocks of Central Kansas" in 
i895.t 
In 1891 Dr. Th. Tschernyschew, the able Director of the 
Russian Comite Giologique and the eminent authority on 
the middle and upper Paleozoic of Russia, attended the 
Washington meeting of the International Geological Con- 
gress and later studied the upper Paleozoic rocks of Kansas 
as exposed along the Kansas river from Manhattan to Fort 
Riley. In his monograph on "Die obercarbonischen Brachi- 
opoden des Ural und des Timan" he reviews the description 
and classification of the upper Paleozoic formations of Kan- 
sas and correlates them with the Russian. Tschernyschew's 
conclusions concerning the correlation of the upper Pale- 
ozoic deposits of Kansas with those of Russia are as follows : 
I have become personally acquainted with the strata of the 
Wabaunsee and Cottonwood during an excursion in the state of 
Kansas, the former in the railway cut near the Manhattan station; 
the latter near the same place in Ulrich's quarry. Both I would 
prefer to put in line with the Cora horizon in eastern and north- 
ern Russia. The Neosho strata, and perhaps also the lower part 
of the Chase, appear analogous to the Russian Schwagerina horizon 
and the remainder of the latter, as also the Marion, one must re- 
gard as homotaxial to the Russian Permo-Carboniferous and lower 
Permian. Finally, the Wellington and Cimarron necessarily cor- 
respond to the lower red colored Permian in eastern and northern 
Russia.* 
The Schwagerina beds form the upper division of the 
unquestioned upper Carboniferous of Russia, while the Cora 
beds form the next older division which is characterized 
by the Brachiopod shell named Productus eora. Succeeding 
the Schwagerina beds is the Artinsk stage of the Russian 
Permo-Carboniferous which is classified by Drs. Freeh and 
Kayser and many other European geologists as lower 
Permian. In my "Classification of the Upper Paleozoic 
formations of Kansas" published in 1902, but a year before a 
copy of Dr. Tschernyschew's Memoir was received, the pro- 
visional line between the Carboniferous and Permian sys- 
t Jour. Geol.. vol. iii, pp. 682-706, and pp. 764-801. 
* Mem. Comity Giologique, vol. xvi, No. 2, 1902. pp. 392, 393. of Russian 
text, and p. 703 of German text. 
