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C. R. KEYES 



is also frequently disseminated. The inferior portion is fossilif- 

 erous. Above this part come other shales, marls, and sand- 

 stones, almost destitute of fossils. They are thought by some 

 authors to be Triassic. 



The passage from the prominent marine phase of the Uralian 

 Carboniferous to the subsequent shallow-water conditions is 

 remarkable. The same closed basin depositions are as note- 

 worthy as in the case of the American. 



General sectio?i. — The Paleozoic beds above the strictly marine 

 Carboniferous, as made out in the Ural region, are grouped by 

 the Russian geologists in the following way: 



UPPERMOST PALEOZOIC TERRANES OF EASTERN RUSSIA 



Faimas represented. — The so-called true Carboniferous of 

 the Urals is made up almost entirely of limestones. The highest 

 member symbolized by the Russian geologists, C 3 , contains a 

 prolific fauna, which, while chiefly brachiopodous, has also a 

 good representation of corals, some lamellibranchs, and fusulinae. 



Following, are the transition faunas to the Permian, accord- 

 ing to the Russians, and by them called Permo-Carboniferous. 

 The two members which comprise it contain, as pointed out by 

 Tschernyschew, very nearly the same organic forms, consisting 

 largely of lamellibranchs, gasteropods, and brachiopods. The 

 lower terrane, termed the Artinsk, is notable for the ammonites 

 that are found in it, which the author just mentioned compares 

 with those lately found in the Texas Permian. The upper 



