235 Devonian of Southern Indiana 107 



that it is found "in the Devonian rocks of the age of the Hamil- 

 ton group. "^- 



In a paper published by Sidney Lyonf in i860 he gives the fol- 

 lowing classification of the Sub-carboniferous series: 



'n. Cavernous limestone. 



o. Middle limestone. 



p. Sandstones and shales. 



q. Black slate. 



r. Encrinital limestone. 

 Sub-carboniferous Series. ^ s. Hydraulic limestone. 



t. Spirifer bed. 



u. Nucleocrinus bed. 



V. Turbo bed. 



vv. Coral beds. 

 ^ X. Catenipora beds. 



Lyon attempts no correlation in this paper of the beds below 

 the Black shale, but is inclined on the evidence of the Rockford 

 Goniatites to place it higher than the Devonian. 



In i860 Hallt had expressed the opinion that the Black shale 

 in Indiana was the "continuation of the Marcellus shale," and 

 that the Rockford limestone was of the same age. 



Meek and \Vorthen|| pointed out the error of this correlation 

 of the Rockford limestone during the next year and affirmed the 

 Genesee age of the Black shale. 



The Report of the State Geologist of Indiana for 1873^ con- 

 tains the following classification of the Devonian in Clark and 

 Floyd counties: 



New Albany Black slate. ^ 



Crinoidal limestone. > Hamilton group ...140 



Hydraulic limestone. ) 



Coruiferous limestone. — Upper Helderberg group 22 



*Am. Jour. Sci., 2d ser., vol. 28, 1859, p. 244. 

 tTrans. St. L. Acad. Sci., vol. i, 1859-60, pp. 612-622. 

 itioth N. Y. Regents' Report, i860, p. 96. 

 ||Am. Jr. Sci., 2d ser., vol. 32, pp. 167-177. 

 ?.P. 172. 



