158 J. J. STEVENSON CARBONIFEROUS OF APPALACHIAN BASIN 



in western Maryland; but no fossils were seen in the second basin within 

 Pennsylvania. 



The Brush Creek limestone of I. C. White (not Brush Creek limestone 

 of Ohio, volume v), separated from the Cambridge in its type area by 

 the Buffalo interval of 30 to 60 feet, is the Black Fossiliferous limestone 

 of the Pennsylvania reports; it is widely distributed in Pennsylvania, 

 Maryland, and northern West Virginia, but it quickly disappears west- 

 ward in Ohio and is wanting in the greater part of that state as well as 

 in Kentucky. Professor Newberry found it occasionally in Columbiana 

 county of Ohio and Professor Orton discovered it at one locality in 

 Guernsey county, 40 or 50 miles toward the southwest. Originally it may 

 have been continuous between these localities and may have been re- 

 moved during deposit of the coarse overlying rock. The limestone is 

 dark, sometimes nodular, carries an abundant marine fauna, and is asso- 

 ciated commonly with black fossiliferous shales. 



The Brush Creek coal bed of I. C. White (in Pennsylvania, Dudley of 

 Broad Top, Eose of Somerset ; Groff and 7 of northern Ohio, Brush creek 

 of southern Ohio; Masontown and Mason in northern West Virginia) 

 is even more persistent than the Harlem around the border of the basin. 

 It has been recognized in Broad Top, in Maryland, in northern West 

 Virginia, in all of the counties of Pennsylvania where its place is ex- 

 posed, and it seems to be equally persistent in Ohio; but it seems to be 

 wanting under the Cowrun anticline and it can not be recognized in 

 the oil-well records. Mr McMillin's section in Lawrence county of Ohio 

 shows the bed double, with the splits 24 feet apart. This coal bed can not 

 be recognized in the sections of northern Kentucky. Coal 10 of Professor 

 E. E. Crandall underlies the Lower Cambridge directly; it rests on the 

 Buffalo sandstone and is very thin. The horizon is a new one, of which 

 no trace appears in the Ohio sections. At one locality only is there any 

 trace of coal at the Brush creek horizon; that is in southeast Carter 

 county certainly 23 miles from the Ohio and on the extreme western 

 outcrop. 



Little reference has been made to the apparently anomalous section of 

 Somerset county within the first bituminous basin of Pennsylvania. There 

 the Conemaugh contains a large number of coal beds and limestones, 

 some economically important, most of which can not be correlated with 

 beds farther west. For the description, the reader is referred to pages 

 which follow. Efforts to recognize these beds led to errors in counties 

 farther west. The Eose coal bed of Somerset is the Brush creek, and 

 above it at a little distance is the Philson, possibly a split from the Eose 



