96 The American Geologist August, loo3. 
erous beds above. From no part of the world have any forms 
been described that could be held to indicate such a fauna as 
that of which Dinichthys and Titanichthys formed prominent 
members, while the whole ichthyic ganoid life of this shale 
shows no striking resemblance to that which specially charac- 
terizes the Devonian elsewhere, even the lower Devonian ; so 
that to break up the system as proposed by Dr. Newberry. 
would involve a loss rather than a gain in geology. And this 
argument gathers strength when extended beyond the Ohio 
basin and to Europe. Speaking for Ohio alone, it certainly ap- 
pears more philosophical to draw a Devonico-Carboniferous 
plane, if we must have one, above the horizon of Dinichthys, 
than to cut that horizon in two and assign the upper part to the 
latter and the lower to the former of these two systems. 
It is, however, in our opinion, more consonant with nature 
and more in harmony with modern views of life to insist less 
strongly on these sharp planes of division, and to regard such 
beds as the Cleveland shale and perhaps the next, often red. 
beds above it as a transition series, representing a time of pas- 
sage from the older era to the newer. Life and evolution are 
continuous, and breaks — so clear to strict systematists — are but 
evidence of our ignorance. 
Acting on this view, I make no attempt to define the upper 
limit of the Devonian in the Ohio basin, but continue the story 
until the general aspect of the Devonian fauna shall have def- 
initely passed away and that of the ensuing era become estab- 
lished. This will probably not occur at the same horizon in 
different places and the faunas may justify difference of opin- 
ion, but for the area now under consideration we believe that 
the fossils occurring in the Bedford shale in ( >hio indicate so 
clear a predominance of the Carboniferous facies over that of 
Devonia, that for that region the story may justly end with the 
Cleveland, shale. 
Similar arguments apply to the eastern side of the Appa- 
lachian gulf and warrant the termination of the Devonian his- 
tory with the Catskill sandstone. The fishes of the lower rocks 
follow up to the top of this stratum hut beyond that horizon a 
Carboniferous aspect becomes strikingly conspicuous in the 
fauna. 
