beede: upper permian red beds. 143 



dontarcas, both foreign and American, but probably more 

 closely related to the American forms, Pleurotomaria capertoni 

 ( Oka-Kljsama or England) , Worthennpns depressa (England), 

 and Oka-Kljasraa Becken, Murchisonia colling sworthensis 

 (Donnez basin), Naticella transversa, to the Carboniferous of 

 Belgium and the Urals and Triassic of St. Cassian. It is to 

 be held in mind that these affinities may be largely superficial, 

 as the preservation of the specimens is such as to obliterate 

 many of the critical characters. However, a comparison of 

 plate IV of Jakowlew's paper on the "Fauna Einiger Ober- 

 palaeozoischer Ablagerungen Russlands" with the last plate 

 of this article can not fail to impress one with the similarity 

 in general aspect. 



The gastropods of the Dozier beds appear to have their clos- 

 est foreign affinities with the Upper Permo-Carboniferous and 

 Lower Permian faunas of the Oka-Kljasma Becken and Ku- 

 logory of Russia, as shown by Jakowlew in the paper cited 

 above. The pelecypods seem closely related to the fauna of 

 the Donnez basin. Cyrtodontarca, described by Jakowlew, 

 is not identical with any of the American species, being more 

 robust and having a slightly different type of dentition. It 

 is perhaps more closely related to C. gouldii, or C. multi- 

 dentata, than to the other species. 



This Russian fauna is from a much older horizon than the 

 species described in this paper. It possesses such peculiar 

 relationships that they deserve wider discussion than the 

 scope of this paper permits, and will be taken up more fully 

 in another paper now nearly ready for the press. It is com- 

 posed of at least two distinct elements, one of which is very 

 closely related to the Upper Pennsylvanian of Kansas and the 

 Middle West, and containing several species in common, such 

 as Michelinia eugenex White, Lophophyllum profundum Milne- 

 Edwards and Haime, Aviculopecten carboniferus Stevens, Ento- 

 lium aviculatum Swallow, Pleurophorus oblongus Meek, Schizodus 

 wheeleri Swallow, Edmondia aspemvallensis Geinitz, and Pleuro- 

 phorus subcuneatus Meek, a Lower Permian species of Kansas. 

 Then there is Cyrtodontarca baheivellioides Jakowlew, related 

 to three species referred to this genus from the Whitehorse 

 and Dozier sandstones, but specifically distinct from them. 



