at tlie Falls of the Ohio. 



171 



;> The Corniferous 

 limestone of 

 Eaton.^ 



1. Marcellus shale. 

 ^2. Limestone with^ 

 Ichthjic remains 

 (bone bed). . . . 

 3. Cherty beds, with 

 species of Loxo- 

 nema, Pleuroto- 

 maria, Bellero- 



Upper Helderberg ^' phon, etc 



group. 4 Corniferous lime- 

 stone 



5. Onondaga lime- 

 stone (the great 



limestone). . . 



6. Schoharie grit. 



7. Oriskauy sandstone. 



In the state of Ohio, Dr. Newberry, recognizes the fol- 

 lowing : 



Hamilton shale. 



Hamilton limestone, 

 f Sandusky limestones. 

 Corniferous group. { Delhi bed. 



(^Columbus limestone. 



^ In the arrangement of Prof. Eaton, all the limestone formation between 

 the Schoharie grit and Marcellus shale was termed " Corniferous lime- 

 stone" — no subdivisions being recognized. In the reports on the Geologi- 

 cal Survey of New York, the subdivision into Onondaga and Corniferous 

 limestones was made for the convenience of reference, and on account of 

 the character of the prevailing fossils in the two members. Further in- 

 vestigation has shown the existence of a peculiar Cherty bed containing 

 characteristic fossils, and also a Calcareous bed with remains of fishes ; 

 both of which are distinct from the Onondaga and Corniferous beds below, 

 but neither of them, apparently, co-extensive with these lower members of 

 the series. The characteristic fossils of the Corniferous or Onondaga lime- 

 stones do not occur in either of these higher members. It is true, that the 

 extent and value of these beds have not been determined ; but they repre- 



