Devonian Era in the Ohio Basin. — Claypole. 93 
nel between the southern Appalachian highlands and the Ozark 
Uplift. As before stated,' the only possible break in this im- 
mense expanse of water was caused by the survival of the Cin- 
cinnati-Xashville promontory or islands. The existence of this 
is doubtful during at least a greater part of the period. Though 
no evidence exists of the submergence of the more northern 
area, except what can be obtained indirectly trom the higher 
outlier of shale, at Bellefontaine, yet the outcrop of the same 
shale around many of the ridges in the central basin of Ten- 
nessee, as well as on its margin, affords ample proof that, so 
far at least and for so long, this area was beneath the sea-level. 
The long Appalachian depression which had gradually nar- 
rowed and intensified its field of action during mid-Devonian 
days now suddenly widened that field again and undid all that 
had been done in the line of elevation in the late Silurian era, 
submerging much that had been dry ever since that time. 
The Cleveland Shale. — The reference of the Cleveland 
shale to the Devonian system in opposition to the view of the 
distinguished author of the monograph* may need a few words 
in its defence. It is well known that the views of the ,late Dr. 
Newberry in regard to the division of this part of the geolog- 
ical column were rather extreme and that he even advocated 
the dismemberment of the Devonian system and the allotment 
of the Chemung and all above it to the Carboniferous. This 
opinion was based more upon stratigraphical grounds than on 
pakeontological arguments. These were also somewhat theor- 
etical. But the changes have not found favor with his fellow- 
workers and the Chemung i- almost invariably retained by 
them in the lower system. 
Professor E. Orton has long maintained that the ' Alio shale 
is not separable into distinct parts and he. consequently, dis- 
credits the divisions of Huron,-Erie and Cleveland adopted by 
Dr. Newberry. His arguments may lie found in the reports of 
the geological survey of ( >hio, where, in its later volumes, the 
question recurs. 
Referring in the monograph to the position taken by pro- 
fessor Orton, Dr. Newberry saws (p. [28): 
'"Prof. Edward- Orton, the present state geologisl of Ohio, has in 
several of his recently published papers united the Cleveland. Erie and 
* "Paleozoic Fishes of Xorth America." J. S. \i; \v hkkr v. Geology <>l <>lii<>. 
vol. i, part ii. Palaeontology, section ii, 1893. 
