1 90 THE JO URN A L OF GEOL OGY. 



state. But of the genera mentioned 'by Meek as being consid- 

 ered not to antedate the Permian of Europe only two are found 

 in the Arkansas strata, namely, Synocladia,^ and Lima. 



There is therefore not sufficient reason for classing the 

 Poteau mountain beds with the Permian, but their fauna, as well 

 as stratigraphic position place them very high in the Coal 

 Measures, since they agree in fauna and position with the Mis- 

 sissippi valley Upper Coal Measures. These beds derive an 

 additional interest from the fact that on Poteau mountain about 

 one thousand feet of shales, in which no fossils were sought for, 

 lie above the thin layer from which the entire collection was 

 taken ; thus the chances of finding true Permian beds in that 

 region are very good. 



RELATIONS TO THE TEXAS UPPER CARBONIFEROUS. 



The only undoubted marine Permian in America has been 

 described by Dr. C. A. White. ^ He finds the fauna of the upper 

 Paleozoic beds of northern Texas, discovered by Professor W. 

 F. Cummins, to be analogous to that of the FusidtJia limestone 

 of Sicily, the Artinsk stage of the Ural mountains, and the 

 upper part of the Productiis limestone of the Salt Range, India. 

 These strata all show that peculiar commingling of ordinary Coal 

 Measure fossils with ammonite genera, such as Popajioceras, 

 Medlicottia, and Waage?ioceras, which seems to be characteristic 

 of open sea facies of the Permian. 



None of the characteristic ammonite genera were found in 

 the Arkansas region, but nearly all the fossils found in the 

 Arkansas Coal Measures are also found in Texas. And in the 

 Texas region nearly all the Permian species excepting the 

 Afnmonites were also found in the underlying Cisco division, 

 which faunally and stratigraphically is the equivalent of the 

 Upper Coal Measures of Arkansas. 



Goniatites {^Gastrioceras^ bayloreiisis White is represented in 



^ Waagen has shown, in Pal. Indica, Salt Range Fossils, I. Productus Limestone 

 Fossils, p. 802, that Synocladia is not found in America, the species described by 

 Swallow as Synocladia biserialis being a Septopora. 



^ Bulletin 77, U. S. Geological Survey. 



