84 THE PERMO-CARBONIFEROUS RED BEDS OF 



numerous non-fossiliferous limestone beds southward as far as Athens County, but 

 beyond that nearly all fail to appear, and in the same area there is a sudden increase 

 in the amount of red beds, thus forming an almost continuous series from the Cone- 

 maugh through the Monongahela uniting with those of the Dunkard." 



On pages 250-260 Dr. Condit gives an account of the deposits of the Cone- 

 maugh formation which might be applied without change to many places in 

 the western Red Beds. He concludes that the beds were deposited in lagoons 

 or on deltas in a region with a rather arid climate which was occasionally 

 flooded by shallow and short-lived invasions of the sea. After comparing the 

 beds with those of the Mauch Chunk as described by Barrel, he concludes: 



"The Permian of the West, characterized by bright colors and beds of gypsum, 

 is a still more striking iUustration of this kind (beds deposited as deltas in a semiarid 

 climate). While evidence of such pronounced aridity is lacking in the Permian 

 (Dunkard) beds of the Appalachian basin, still it is evident that conditions were 

 somewhat similar. It is believed that the appearance of the red color in the Cone- 

 maugh marks the beginning of the Permian. In southern Ohio, where the Monon- 

 gahela coals and limestones are scantily developed, the red beds are practically 

 continuous from the Conemaugh through the Monongahela, uniting with those of 

 the Dunkard." 



The author has examined a fragment sent to him by Dr. Bownocker and 

 which is undoubtedly that of a fish. Unfortunately other fragments, upon 

 which the presence of amphibians and reptiles were determined, have been lost. 



PENNSYLVANIA AND WEST VIRGINIA. 



Fossil vertebrates closely related to those of Texas have been found near 

 Pittsburgh, Pennsylvania, in a shale just beneath the Ames limestone. The 

 beds in which these fossils were found are described by Raymond,^ the dis- 

 coverer, as follows: 



"The bones are from the upper part of the formation which I. C. White has 

 named the Pittsburgh red shale (Geol. Survey West Virginia, vol. 2, p. 263). This 

 formation is usually from 100 to 125 feet thick in the vicinity and consists of red 

 clays and red and yellow sandstones. At the top there is a bed of almost structure- 

 less clay, which varies from 18 to 40 feet in thickness. At Pitcairn the clay is 37 

 feet thick, and the fossils were found 4 feet above the base of the clay. Three feet 

 above the base of the clay there is a layer of nodular limestone, and the teeth were 

 found lying on this layer where it projects from the bank on the roadside. The other 

 bones were all imbedded in the clay about i foot above the limestone. On the 

 Pittsburgh shale rests the Ames limestone, the youngest of the marine limestones in 

 the region. It is almost exactly in the middle of the Conemaugh series. It is 315 

 feet below the base of the Pittsburgh coal, and 695 feet below the base of the 

 Dunkard series (Permian). The Ames limestone is about 300 feet above the Free- 

 port coal (top of the Allegheny series)." 



The Pittsburgh red shale is described by White :'' 



"As a rule the Friendsville coal, or, in its absence, the Ames limestone, rests 

 directly upon a soft red or purple shale, which, from its fine exposure along the grade 



° In Case, Annals Carnegie Mus., vol. IV, Nos. Ill and iv, p. 234, 1908. 

 i* White, West Virginia Geol. Surv., vol. 11, pp. 263, 264, 1903. 



