66o JESSE E. HYDE 



unknown) are merely a facies of the Cuyahoga, and the attempts, 

 particularly by Orton, properly to place these conglomerates in the 

 Waverly column led to confusion. He included the Black Hand 

 with Andrew's Logan under the term Logan Group, a procedure 

 that has been followed by many. 



Yet, in spite of the fact that these names are now made to denote 

 the same beds that they denoted in the earliest usage in central Ohio, 

 a question may be raised by some whether they should be retained ; 

 whether it is established that these subdivisions are two chief 

 subdivisions, and that a classification which would drop one or 

 both terms and place some of the members here proposed in a 

 higher rank would not more nearly indicate the true relations. 

 Prosser in his work in northeastern Ohio has dropped the term 

 Cuyahoga^ and builds this portion of his Waverly column out of 

 members which were formerly units within the Cuyahoga. From 

 this it would appear that he does not regard the Cuyahoga shale, 

 as delimited by Newberry in northern Ohio, as a terrane of 

 established stratigraphic significance. 



Apropos of this question it may be remarked that in the present 

 work it has been found exceedingly convenient to retain both. 

 The classification of the Cuyahoga of central and southern Ohio 

 here proposed with its numerous members in different facies is 

 very complex; nevertheless, when the entire area is considered, 

 it appears that these groups of members constitute a distinct ter- 

 rane, for no one of its members in any facies can be satisfactorily 

 discussed except in connection with the other members of that 

 facies. Furthermore, the Berne member, whether it be regarded 

 as closing the Cuyahoga or opening the Logan, separates two groups 

 of sediments that are essentially different from each other in many 

 ways. The retention of the term Logan is necessary, for although 

 easily subdivided into three important members over most of this 

 area, along its southwestern margin it is not so divisible and one 

 name is needed to denote sediments that are there the equivalent 



I "The Devonian and Mississippian Formations of Northeastern Ohio"; Geol. 

 Sun. Ohio, 4th ser., Bull. 15 (1912), 574 pp. 



