CORRELATION OF CONEMAUGH FORMATION 155 



higher one often almost directly under that coal. Sometimes these lime- 

 stones are brecciated and they frequently contain minute univalves, whose 

 relations have not been determined. 



The Little Pittsburg coal bed of H. D. Kogers refers to a horizon 

 rather than to a single coal bed. At varying intervals down to 50 feet 

 below the Pittsburg coal bed, one or at times two coal beds are seen, 

 usually thin, but occasionally, as in the case of the Jeffers (E. B. 

 Andrews) in southern Ohio and possibly in western Maryland, attaining 

 local importance. Non-fossiliferous limestone is present in some localities 

 associated with the coal. 



The Little Clarksburg coal bed of I. C. White, frequently accompanied 

 by a limestone, is a well marked horizon at 100 to 130 feet below the 

 Pittsburg; but it is confined to southern Pennsylvania and northern 

 West Virginia, being unrecognizable at any considerable distance west 

 from Chestnut hill, in the former state. Like many other coal beds, its 

 only representative at times is a black shale containing fragmentary re- 

 mains of fishes. 



The Elk Lick coal bed of J. P. Lesley (Barton of Pennsylvania reports 

 L and K) is an important bed at the type locality in Somerset county of 

 Pennsylvania. The horizon is marked by a thin coal bed at many locali- 

 ties in Pennsylvania and northern West Virginia, while in Ohio it of tens 

 carries thin coal or black shale. Its place is well defined on the east side 

 of the basin, as it underlies the rather persistent Morgantown sandstone. 

 On Elk creek it overlies the Elk Lick limestone, but that bed is uncertain 

 elsewhere, having been observed very rarely outside of Somerset county. 



The Ames limestone of E. B. Andrews (Crinoidal of northern Ohio. 

 Green Fossiliferous and Crinoidal of Pennsylvania) is one of the most 

 persistent and in some respects the most remarkable horizon in the 

 Conemaugh. It is wanting, or perhaps not recognized, in the northern 

 portion of the first and second bituminous basins of Pennsylvania, but is 

 present in the southern portions of those basins in Pennsylvania, Mary- 

 land, and West Virginia. Though thin, seldom more than 6 and often 

 less than 3 feet thick, it has been followed in exposed sections from 

 Barbour county of West Virginia along the eastern and northern outcrops 

 in Maryland and Pennsylvania into Ohio, where it persists along the 

 western outcrop to the last exposure of its place near the Kentucky line; 

 and in this last state it may be the fourth fossiliferous limestone of 

 Professor CrandaH's sections, which is present certainly as far south as 

 the middle of Lawrence county. Southward from Barbour county of West 

 Virginia, along the eastern outcrop, it has not been reported, but Doctor 

 White has identified it with the Two-mile limestone near Charleston, a 



