

46 Upper Coal Measures of 



either margin, those of the centre converging and meeting before reach- 

 ing the lower margin, as in Cylindrella, &c. The jaw appears therefore 

 to be of the same type as in Bulimuhis, Gceotis, Amphibulima, Cylindrella, 

 Macroceramus and Pineria. The ribs, however, are in Partula exceed- 

 ingly fine. 



The lingual dentition of the species mentioned above is the same as 

 figured by Heynemaun (Mall. Blatt. 1867, pi. i, fig. 1,) excepting that I 

 detect distinct cutting points to the side cusps of the central teeth, not 

 figured by him. 



V. — Notes on the Upper Coal Measures of West Virginia 



and Pennsylvania. 



BtI.C. white. 



Read May 25th, 1874. 



In this paper I propose to describe that part of the coal 

 measures known as the Upper Barren Group, and also to 

 make such remarks on the Upper Coal Group proper, as 

 may be deemed of interest. 



The district under consideration includes portions of Mo- 

 nongalia, Marion, Marshall, and Ohio counties, W. Va., and 

 Green Co., Penn. ; and the section extends from the Pitts- 

 burgh coal on the Monongahela River near Morgantown, W. 

 Va., across the basin to the same coal near the Ohio at 

 Wheeling. 



Almost midway between Morgantown and Wheeling, 

 there rises in Pennsylvania, and extends south into West 

 Virginia, what is locally known as the "Dividing Ridge," 

 since it forms the watershed between the tributaries of the 

 Monongahela, and those of the Ohio. 



This seems to occupy the median line of a gentle uplift, 

 or anticlinal axis, which passes across the coal measures from 

 north to south. As a consequence of this anticlinal, about 

 fifteen miles west of Laurel Hill, we find the dip changing, 

 and thenceforward the strata rise gently westward until the 

 "Dividing Ridge" is crossed, beyond which, the dip is again 



