368 The Ohio Journal of Science [Vol. XIX, No. 7, 



Ontario and the Cedarville dolomite of the more northern 

 counties in Ohio. 



The fossils cited by Prof. Orton from the Lower or West 

 Union Cliff are found in a limestone layer occurring from 8 to 10 

 feet above the base of the formation. This is a continuous 

 and very fossiliferous horizon throughout Highland and Adams 

 counties, in Ohio, and occurs as far south as Martins, in Lewis 

 county, in Kentucky. In the Fauna of the Bisher member 

 of the West Union formation, listed on a following page, all 

 of the fossils cited from Hillsboro, Danville, Sinking Springs, 

 Crooked Creek, Peebles, West Union and Martins came from 

 this horizon, while the remainder came from approximately 

 the same zone. Fossils from the James Sanderson locality 

 are here listed as from Danville. 



Among the fossils cited by Prof. Orton from the Upper or 

 Blue Cliff are Hal y sites, Favosites and Zaphrentid corals identi- 

 fied by him as Streptelasma. The spherical concretions stated 

 to be common in Marshal township, in Highland county, 

 unquestionably are a form of Stromatoporoid. 



The rock identified as Guelph or Cedarville contains in the 

 Hillsboro area a considerable abundance of Pentamerus oblongus. 

 Afegalomus canadensis, Trimerella aciiminata, Trimerella grandis, 

 and Trimerella ohioensis are listed by Prof. Orton from this 

 rock. In the Hillsboro area, according to Prof. Orton, Mega- 

 lomus canadensis and Pentamerus oblo?igus occur more or less 

 associated, although in very unequal numbers. Farther east- 

 ward and southward, however, in Ohio, Megalomus and Trime- 

 rella occur in strata above the Pe^itamerus containing layers, 

 whenever the latter occur, which is rarely the case. 



While the various observations of Prof. Orton on the faunas 

 of the Lower Cliff, Blue Cliff, and Guelph formations of High- 

 land county and of the neighboring Adams county are confirmed 

 by later investigations, they are not sufficiently detailed to 

 serve to correlate the southern Ohio strata here mentioned 

 with those occurring elsewhere. To supply the necessity 

 for more detailed information, at least in part, the following 

 lists of the fossils found in the Bisher and Lilley members are 

 provided, accompanied by a description of some of the less 

 known forms. The Bisher member here corresponds to the 

 Lower or West Union Cliff of Orton, while the Lilley member 

 corresponds to the Upper or Blue Cliff. 



