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state. But of the genera mentioned by Meek as being considered not to antedate the Permian of Europe only two are found in the Arkansas strata, namely, Synocladia,^[1] 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 Mississippi 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.

The only undoubted marine Permian in America has been described by Dr. C. A. White.^[2] 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 Fusulina limestone of Sicily, the Artinsk stage of the Ural mountains, and the upper part of the Productus limestone of the Salt Range, India. These strata all show that peculiar commingling of ordinary Coal Measure fossils with ammonite genera, such as Popanoceras, Medlicottia, and Waagenoceras, 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 Ammonites were also found in the underlying Cisco division, which faunally and stratigraphically is the equivalent of the Upper Coal Measures of Arkansas.

Goniatites (Gastrioceras) baylorensis White is represented in