212 



CHARLES S. PROSSER 



In 1888 Dr. Orton published a general classification of the 

 Waverly group which he considered as composed of the Bedford 

 shale, the Berea grit, the Berea shale, the Cuyahoga shale, and 

 the Logan group. The Cuyahoga shale, however, was restricted 

 to the shales and fine-grained sandstones between the Berea 

 shale and the base of the conglomerate and sandstone forming 

 the upper part of the Waverly. This upper division was called 

 the Logan group which was said to consist of the Waverly con- 

 glomerate and Logan sandstone of Andrews as found in Hock- 

 ing, Fairfield, and Licking counties. To the north the olive 

 shales of Read in Knox and Richland counties were correlated 

 with the Logan sandstone. 2 The same classification was repub- 

 lished by Dr. Orton in his last report for the Ohio survey. 3 



In 1888 Professor C. L. Herrick, who had studied the 

 paleontology and stratigraphy of the Waverly series of central 

 Ohio more thoroughly than any of the former observers, pub- 

 lished his conclusions. Professor Herrick had also studied the 

 Waverly of northern and southern Ohio and rocks of similar age 

 in Pennsylvania and western New York, so that his classifica- 

 tion was not intended to be confined to the rocks of central 



x Ibid., Vol. XVIII, p. 139. 



2 Kept. Geol. Surv., Ohio, Vol. VI, pp. 33-42. 



mid., Vol. VII, 1893 [1895], pp. 26-35. 



