672 J. W. BEEDE BEDS OF APPALACHIAN AND WESTERN SECTIONS 



possesses unity of expression and is characterized by relatively little evo- 

 lution when the great length of time involved is considered. The larger 

 formations, or stages, are characterized by the introduction of a few dis- 

 tinctive species and the extinction or disappearance of others, together 

 with the fact that certain persistent forms found throughout great thick- 

 nesses of strata become very abundant in certain horizons. A number of 

 species run the gamut of the formations of the middle and upper parts 

 of the Pennsylvanian. 



The data on which these generalizations are based is shown in detail 

 for the Kansas section in volume IX of the University of Kansas Geo- 

 logical Survey Eeports. 2 



A glance at the Kansas faunal chart shows a continuous diminution of 

 the number of species in the formations after the Oread limestone, the 

 top of the Douglas stage, is passed. Many new forms are introduced in 

 the higher formations shown on the chart. If still higher beds in the 

 Kansas- Oklahoma succession had been included, the number of added 

 species would have been considerably larger. 



Subsequent to the publication of this work, data became available which 

 made it advisable to consider the base of the Neva limestone as the base 

 of Series IV, the base of the Permian, instead of the base of the Elmdale 

 formation. This increases the number of species found in Series III by 

 those that are first recorded in the Elmdale formation and diminishes the 

 number found in Series IV, namely, a loss of ten species to Series IV and 

 the addition of eight species to Series III. Since the chart was com- 

 pleted additional work in Oklahoma has added somewhat to the fauna 

 that is accredited to Series IV, to a considerable extent by the addition 

 of species not known from the formations below it. The numerical rela- 

 tionships of the species has been discussed elsewhere. 3 



Similar detailed charts were prepared by Miss Mark for the fauna of 

 the Conemaugh formation of Ohio, 4 in which the Ohio faunas are com- 

 pared and correlated with those of the Kansas section. The lower Cone- 

 maugh formation of Ohio is more typically marine in Ohio than in West 

 Virginia and possesses a correspondingly richer fauna, Miss Mark's lists 

 containing 1G8 species. This fauna is strictly Pennsylvanian in its char- 

 acters, and Miss Mark correlates its highest horizon, the Ames limestone, 

 approximately with the Oread limestone of the Kansas section, and its 



2 Beede and Rogers : Faunal studies of the Kansas Coal Measures. Univ. of Kans. 

 Geol. Survey, vol. ix, 1908, pp. 318-385. See especially the chart facing page 328. 



3 Jour. Geol., vol. xvii, 1909. pp. 710-729. 



4 Clara G. Mark: Fossils of the Conemaugh formation in Ohio. Ohio Geol. Survey, 

 4th series, Bull. 17, 1912, pp. 261-326. 



