422 CHARLES S. PROSSER 



twenty-five feet of impure bluish limestone," 1 although under the 

 account of the Corniferous limestone the Delaware is mentioned as 

 the upper division in Ohio. 2 



In 1898 Professor John A. Bownocker published a paper on "The 

 Paleontology and Stratigraphy of the Corniferous Rocks -of Ohio," 

 in which is given a number of sections of the limestone as shown 

 in various quarries, accompanied by lists of fossils collected at twelve 

 different localities in the state. The Corniferous limestone of this 

 article includes both the Columbus and Delaware divisions, and at 

 the close of the discussion on the "Relation of the Fauna above the 

 Bone-Bed to that Below" it is stated: 



It appears, therefore, that the difference between the faunas above and below 

 the bone-bed in the central Ohio area is not great, that this difference is most 

 conspicuous at Delaware and diminishes to the north, being least at Sandusky. 3 



Dr. Edward M. Kindle carefully studied the Devonian limestone 

 of southern Indiana and northern Kentucky, and stated that near 

 the Ohio River it "is readily separated into two divisions, which are 

 easily distinguished from each other both by lithological and paleon- 

 tological characters." 4 The lower division he named the " Jefferson- 

 ville limestone" and the upper one the "Sellersburg beds." Kindle's 

 Bulletin was based on a thorough study of the fossils, and in discussing 

 the "Correlation of Faunas" he stated: 



The Corniferous fauna of New York suffers no very important modifications 

 in its western extension. The large number of species common to the faunas of 

 the Corniferous limestone of New York and the Jeffersonville limestone, especially 



among the corals, leaves no doubt as to the equivalence of the two faunas 



In southern Indiana we find in the Sellersburg beds a fauna containing many of 



the most characteristic species of the Hamilton of New York This fauna 



is not mingled with the Corniferous, as was once supposed, but occurs above that 

 fauna in the Sellersburg beds. The presence in it of such characteristic Hamilton 

 fossils as those mentioned seems to leave no doubt of its equivalence to the New 

 York Hamilton. 5 



It will be noticed that this conclusion regarding the correlation of 

 these limestones is in perfect harmony with the later views of Professor 

 Hall. 



1 Manual of Geology, 4th ed. (1895), p. 592. 2 Ibid., p. 581. 



3 Bulletin of the Scientific Laboratories of Denison University, Vol. XI, p. 39. 



4 Bulletin of American Paleontology, No. 12 (1899), p. 8. s Ibid., p. no. 



