io8 
BULLETIN OF 1 HE LABORATORIES 
rarely exceeds sixty feet, but the superposed shales frequently become 
flags resembling it closely. These flags have yielded Atrypa reticularis 
and Strophomena rhomboidalis, the latter species, however, in the un- 
disturbed deep sea fauna farther east, endured until the beginning of 
division iii. The only other fossils known from the Bera grit are 
found in the bitumenous layers overlying the grit. They are Orbicu- 
loidea newberryi and Lingula melie. 
In the northern part of the state the Berea is more distinct and 
may be divided into the lower or grind-stone grit and the upper or 
flag-stone division. The following section in Lorain and Medina 
counties will sufficiently illustrate the relations : 
Carboniferous conglomerate 25 ft. 
f Shales with Chonetes illinoisensis, numerous bryozoa, etc 65 ft. 
Cuyahoga etc ^ Blags and shales with Spirifer biplicatus, Productus new- 
’ ' I berry i, etc 35 ft. 
I Ferrugineous freestone with many fossils 20 ft. 
(Middle Waverly, absent.) 
f Shales with concretions with Strophomena rhomboidalis 
Waverly and J and fossils of horizon 80 feet below congl. I mingled 
Berea shales | with those of division III 30 ft. 
[ Unseen (perhaps) 150 ft. 
Berea Grit. 
f Berea flags 
\ Grindstone grit 
-40 ft. 
_20 ft. 
Bedford shale, (green and red) 
50 ft. 
6. T/ie Bedford shale. 
This member of the series has been the occasion of much per- 
plexity. The so-called choccolate shales of central Ohio have fre- 
quently been identified with the Bedford of the lake region upon litho- 
logical grounds alone, the southern exposures being thought un.'ossili- 
ferous. As a matter of fact, they are everywhere abundantly fossil fer- 
ous. Especially prolific exposures occur near Central College, O. A 
number of the species occurring there are figured on Plate IX, and 
several of the same species are abundant in Summit county near Pen- 
insula. One is at once struck by the fact that the group of forms here 
associated has nothing in common with either the Erie shale fauna or 
that of known exposures of the Waverly. The stratum rests directly 
on the the Hamilton* for much of its extent but overlaps the Erie shales 
in the north-eastern counties. Another fact is equally striking. The 
■*Prof. Orton, indeed, identifies the Cleveland shale in central Ohio, but in 
this we are unable at present to concur. 
