4i 6 CHARLES S. PROSSER 



The lithological characters of the Michigan Hamilton are the same as those 

 of the upper Corniferous in Ohio, and it is hardly susceptible of doubt that they 

 are stratigraphically identical. 1 



In his sections Professor Winchell used the names "Tully limestone," 

 and "Hamilton," followed in the descriptive part by an interrogation 

 point, and "Corniferous limestone." 2 The upper limestone is also 

 mentioned under the name of "Delaware stone" 3 and "Delaware 

 limestone," 4 but apparently without the intention of considering it as 

 a formation name. Later, however, in describing Paulding County, 

 in the northwestern part of the state, Professor Winchell stated that 

 close "attention was paid to the solution of the question, 'Do Hamil- 

 ton fossils extend through the whole of the blue limestones?'" 5 and 

 the conclusion was "that the beds that hold these Hamilton fossils 

 are very near the bottom of the blue limestone." 6 Professor Winchell 

 accepted this as sufficient proof of the correctness of his correlation 

 with the New York formations, consequently on his " General Section 

 of the Rocks of Paulding and Defiance Counties" appear the names 

 "Tully limestone" and "Hamilton limestone of New York," below 

 which are given the "Corniferous and Onondaga limestones of New 

 York." 7 In the legend of the geological maps of Delaware, Paulding, 

 and Defiance Counties, all by Professor Winchell, appears the name 

 "Hamilton group," 8 which is given a distinct area on the maps. 

 This correlation was opposed by Dr. Newberry, who said: 

 The Tully limestone ? of Professor WinchelFs sections is certainly Hamilton, 

 as I have obtained from it Tropidoleptus carinatus, Pterinea flabella, Nyassa 

 arguta, Spirifera mucronata, etc. 



And regarding the Hamilton limestone of Professor Winchell he wrote 

 as follows : 



I think it will be seen that the weight of evidence is decidedly in favor of its 

 being of Corniferous age. The cherty layers which lie between the Huron shale 

 and the quarry-stone at Delaware are probably Hamilton, but the quarry-stone 



1 Ibid., Vol. II, Part I (1874), p. 289. 



2 For example, see the section "through the Olentangy Shale and Hamilton 

 Limestone, Five and a Half Miles below Stratford," on pp. 293, 294. 



3 Ibid., pp. 293, 302. 4 Ibid-, p. 294. s Ibid., pp. 341, 342. 



6 Ibid., p. 343. The statements just quoted also appeared on pp. 395, 397, of 

 the excerpt from the report on Paulding County, entitled "On the Hamilton in Ohio," 

 published in the American Journal of Science, third series (1874), Vol. VII. 



7 Ibid., p. 342. 8 Ibid., facing pp. 272, 336, and p. 422. 



