THE CINCINNATI GROUP 43 



north of Fernvale, the limestone contains Orthis proavita, Diiior- 

 this siibquadrata, Hebertella insculpta, and Strophomena rugosa sub- 

 tenta. The clay shale immediately above the limestone appears 

 to be unfossiliferous. 



Richmond limestone is exposed three miles north of the Fore- 

 hand locality, along the banks of the Harpeth river, at Newsom. 

 It is a coarse-grained limestone, varying from bluish to light 

 brown, and at least lo feet thick. Its age is indicated by the 

 presence of a single ventral valve of Diiiorthis subquadrata, show- 

 ing the muscular scar. The unexposed part of the section, 

 between the Richmond limestone and the base of the Clinton, 

 may be occupied by Richmond clay. 



The most northern exposure of Richmond limestone, equiva- 

 lent stratigraphically to the Leipers creek limestone, occurs at 

 Baker, twent3'-three miles northeast of Newsom. Here it is four 

 feet thick, is a coarse-grained limestone, and contains Stropho- 

 mena Wisconnne7isis, or at least a form closely resembling this 

 species in general appearance. No Richmond shale was noticed. 



6. Swaji Creek Limestofie. — At Newsom the coarse-grained 

 limestone is underlaid by clayey rock which contams numerous 

 specimens of the form identified in Ohio and Indiana as Dalma- 

 7iella jiigosa ; it there extends from the upper beds of the Lorraine 

 through the lower part of the Richmond; the dorsal valve is 

 slightly convex. Four typical specimens of Rhy?ichotrema de7xta- 

 tum were found. The presence of a single specimen of Platystro- 

 phia lynx with a short hinge line suggests the Lorraine age of this 

 rock. The thickness of the clayey rock is not known, only a few 

 feet being exposed above the level of the river. 



Platystrophia lynx was also noted below the Leipers creek bed 

 at the Inman locality, a mile southeast of Fernvale. 



At the J. M. Gardner locality the Leipers creek limestone is 

 underlaid by a considerable thickness of more or less cross- 

 bedded limestone containing very few fossils, and this in turn is 

 underlaid by clayey limestones in which fossils are numerous. 



All along the Swan Creek valley, cross-bedded Ordovician 

 limestone containing very few fossils is very well exposed. At 

 the spring, a quarter of a mile south of Swan Bluff, it measures 



