STRATIGRAPHIC SUMMARY. 641 



Middle Kittanning coal, (9) Johnstown Cement lime, (10) Upper 

 Kittanning coal, (11-13) Lower Freeport sandstone, limestone 

 and coal, (14) Middle Freeport coal, (15) Upper Freeport sand- 

 stone, (16) Upper Freeport limestone, (17) Bolivar fire clay, 

 (18) Upper Freeport coal, the Uffington shale (19) of West Vir- 

 ginia, forming the roof shale of the Upper Freeport ; it is also a 

 marine horizon. 



The Conemaugh series contains a number of limestones but those 

 above the Ames are generally non-marine. The more important mem- 

 bers of the series are, in ascending order: (1-3) Lower and Upper 

 Mahoning sandstone including Mahoning coal, (4) Mason coal, (5) 

 Lower Cambridge limestone, (6) Buffalo sandstone, (7) Upper Cam- 

 bridge limestone, (8) Bakerstown coal, (9) Saltzburg sandstone, 

 (10) Pittsburg Red shale, (11) Friendsville coal, (12) Ames or 

 Crinoidal limestone, (13) Birmingham shale and Skelly limestone 

 (marine), (14) Elk Lick coal, (15) Morgantown sandstone, 

 (16) Clarksburg limestone, (17) Little Clarksburg coal, (18) Con- 

 nellsville sandstone, (19) Pittsburg limestones, (20) Little Pitts- 

 burg coals, (21) Lower Pittsburg sandstone. 



The Monongahela series comprises a number of beds of greater 

 or less distribution in the bituminous area of western Pennsylvania, 

 Ohio and West Virginia. Some of them are in ascending order: 

 (i) Pittsburg coal, (2) Pittsburg sandstone, (3) Redstone lime- 

 stone, (4) Redstone coal, (5-7) Sewickley limestone, coal and 

 sandstone, (8) Great limestone, (9) Uniontown coal, (10) Gilboy 

 sandstone, (11) Little Waynesburg coal, (12) Waynesburg coal. 



The Dunkard series includes the following important members 

 (ascending order): (i) Cassville Plant shale, (2) Waynesburg 

 sandstone, (3) Waynesburg "A" coal, (4) Marietta sandstones, 

 (5) Washington limestones, (6) Jollytown coal, (7) Dunkard 

 coal, (8) Fish Creek sandstone, (9-1 1) Nineveh limestone, coal 

 and sandstone, (12) Gilmore sandstone, (13-14) Windy Gap coal 

 and limestone. 



In southwest Indiana, Illinois and part of Kentucky, various 

 Mississippic beds are disconformably succeeded by the Mansfield 

 sandstone^ above which occurs the Wabash group (100-600 ft.) 

 and the Merom group (0-400 ft.). The latter may be of Permic 

 age. 

 41 



