DUNKARD FOEMATTON 99 



west Fayette, eastern Greene, and southern Washington of Pennsylvania. 

 Even there it is irregular, being absent at many places where its horizon 

 is fully exposed. The Little Washington coal bed (J. J. Stevenson, 

 1876) has miich the same distribution as that of Waynesburg B, but the 

 area is somewhat smaller. 



A limestone, the Mount Morris (I. C. White, 1891), sometimes under- 

 lies the Waynesburg A coal bed, but it seems to be confined to small 

 spaces. The typical locality is in southeastern Greene, but limestone is 

 found occasionally at this level in West Virginia and eastern Ohio. The 

 Colvin limestone (I. C. White, 1891), la of the Pennsylvania volume K, 

 is just above the coal bed and is present in Payette and most of Wash- 

 ington county. It was seen at many places in eastern Greene, but is 

 wanting in the western part of that county and is irregular in the south- 

 em part. It attains considerable thickness in Washington, but is usually 

 thin in Greene. It barely enters West Virginia at the south. Another 

 limestone, termed I& by Stevenson, is apparently confined to five town- 

 ships in the west central part of Washington county, where it attains a 

 maximum thickness of 10 feet. These limestones are all either non- 

 fossiliferous or contain at most some indeterminate forms related to 

 freshwater types. The rock is not magnesian in any case and sometimes 

 the lime obtained from it is of excellent quality. The source of these 

 calcareous muds is uncertain. 



The Washington sandstone (J. J. Stevenson, 1876), underlying the 

 Washington coal bed, is curiously persistent. Earely more than 12 feet 

 thick, it accompanies the Washington coal bed throughout Washington 

 and Greene of Pennsylvania, Ohio and Monongalia of West Virginia, 

 everywhere showing the same features. How much farther it extends 

 is not known. It is thinly laminated, often crowded with fragments of 

 carbonized vegetable matter, but seldom contains a leaflet in recognizable 

 condition. Very often it is seamed vertically, and the slender seams are 

 filled with lead-colored clay belonging to an underlying bed. These 

 seams have no relation to jointing in the overlying and underlying coal. 



The interval between the well marked Waynesburg and Washington 

 coal beds shows the same kind of variation as that between the Waynes- 

 burg and Uniontown. At the extreme northern exposure of the Wash- 

 ington in Smith and Jefferson townships of Washington county, Penn- 

 sylvania, it is 50 feet above the Waynesburg. As one goes southwardly 

 along the western side of the county he finds the interval 65, 83, 90, 95, 

 110, and 130 feet at the southern part of the county, beyond which in 

 Greene the upper bed soon passes under. In a southeastward direction 

 tiie interval becomes 65, 90, 110, 120, 125, and 142 and at the Greene 



