508 GEOLOGY OF OHIO. 



was found near Central college, near Westerville. If there is substantial 

 continuity up to the Bedford, an equally close transition connects the 

 latter with the following. 



The Berea Grit. 



This very constant and well-marked stratum has been most ex- 

 haustively described by Professor Orton, in volume VI of the Ohio re- 

 ports. It is exceedingly poor in fossils and with the exception of 

 Strop homena rhomboidalis and a few lingulse, these are not identifiable. 

 In all probability the fauna was identical with that of the next. 



The Berea Shale. 



This layer of black bituminous shale which forms the immediate 

 •cover of the grit, contains besides fish remains a vast number of Lingula 

 melie and Discina newberryi wherever it occurs throughout the State. 

 In northern Ohio the same fauna, supplemented by other species of 

 Lingula, is continued some distance higher. 



The writer has in previous papers extended the term to the gray 

 and greenish shales following, which, as admitted by Professor Orton, 

 cannot be sharply separated. The faunal similarity would warrant such 

 a procedure, but it has the obvious disadvantage of leaving the upper 

 limit of the Berea shale ambiguous. It will be preferable to restrict the 

 term to the bituminous portion with the understanding that it is but a 

 lithological modification in a continuous series. It can hardly be doubted 

 at present that the Berea grit is the real floor of the series — not necessar- 

 ily the base of the Carboniferous, but the most convenient base line for 

 the Waverly, if this term is still to be used for this remarkable series of 

 Ohio shales and flags. 



The Cuyahoga Shale. 



In deference to the usage of the Ohio geologists, this term is here 

 used to embrace everything between the Berea shale and conglomerate 

 I, but it should be remembered that in fauna this series is not homo- 

 geneous but presents at least a three-fold subdivision. The lower courses 

 contain beds of flags in southern and central Ohio, of which the Buena 

 Vista beds are the most important. In Scioto county these beds follow 

 immediately the fifteen feet of Berea shales and attain a thickness 

 of twenty -five feet. In central Ohio, while less distinctively developed 

 they nevertheless can be recognized. They are followed by a few feet 

 of shales, which have yielded to a long continued search only a few 

 specimens of imperfectly preserved fossils. 



Several daj's' labor during which the shale was systematically exam- 

 ined bit by bit, inch by inch, have yielded about half a dozen species in 

 obscure fragments. A spirifer apparently intermediate between Sp. 



