558 Heviews — Geological Survey of Ohio. 



a long strip of country. This is the " Waverley Group, "^ a series of 

 sandstones and grits, conglomeratic towards the middle of the series, 

 and shaly near its base, in all some 640 feet. This important set of 

 beds is supposed to represent the Lower Limestone shales of Europe. 

 The " Upper Waverley " or " Logan Sandstone" as it is locally called, 

 contains several forms of marine plants, but no animal remains. 

 The latter are very scarce throughout this formation apparently, a 

 single indistinct Cyathophylloid coral having been obtained in one 

 layer known as the " Gitj Ledge," and two Brachiopods and some 

 unimportant fish remains in black bituminous shale near the bottom 

 of the series. 



The lower beds of the " Waverley " contain a considerable amount 

 of mineral oil, which, however, has its origin not in them, but in the 

 "Huron shale" or "Black Slate," which underlies them along most 

 of their course. 



This brings us to a point in the stratigraphical structure of the 

 Slate, at which sections of the rocks cropping out in its southern and 

 northern portions respectively would no longer tally. The cause of 

 this is, that several great deposits lying in their proper order along 

 the shores of Lake Erie gradually thin out as their outcrops trend to 

 the south to such an extent as to disappear entirely before reaching 

 the banks of the Ohio, which river forms the southern and south- 

 eastern boundaries of the State. This arrangement will be best 

 understood thus : — 



Formations prom the " "Waverley Group " domtstwards. 

 la the North of Ohio. In the South of Ohio. 



Waverley Waverley 



■5 / Erie shales ' (absent) 



^ \ Huron shales Huron shales 



§ -/ Hamilton Group (absent) 



> ] Corniferous Limestone (absent) 



fi \ Oriskany Sandstone (absent) 



^ / Water-lime and Salina Group (absent) 



g I Niagara Group Niagara Group 



P j (not at surface) Clinton Group 



J2 ' (iio'' 3,t surface) Cincinnati Group 



The "Erie shales" which skirt the lake of that name have been 

 conclusively shown for the first time by the present survey to be the 

 equivalent of the " Chemung (xroup" of New York Geologists, the 

 characteristic fossils of which {Spirifer Verneuilii, Leiorhynchus 

 mesocostalis, etc.) have been found in it in considerable numbers. 



These beds, 400 feet thick in the north, and absent in the south, 

 form the summit of the Devonian rocks; the oil-produchig "Huron 

 shales," which have a continuous outcrop across the State, coming 

 next. In some calcareous concretions occurring near the base of the 

 latter, Mr. Hertzer has recently discovered the remains of gigantic 

 fishes, to the most remarkable of which the name of Diniclithys 

 Hertzeri has been applied. Respecting this monster Dr. Newberry 

 says : " This name [Hertzer's terrible fish] will not seem ill-chosen 

 when I say that the fish that now bears it had a head three feet long 

 by two feet broad, and that his under-jaws were more than two feet 

 in length and five inches deep. They are composed of dense bony 



