Devonian Era in the Ohio Basin. — Claypole. 313 
cranium has been recognized and we are consequently ignor- 
ant of the rest of its structure. 
Besides the two above named species great chimaeroid 
fishes, the Rhynchodi with heavy crushing teeth or jaws — im- 
mensely magnified representatives of Chimaera — also tenanted 
the Corniferous and Corniferous-Hamilton seas. Acanthaspis 
and Acantholepis — lineal descendants of the pteraspids and, 
perhaps, of Pal?easpis, represented that ancient family in the 
Devonian waters, while the elasmobranchs if not numerous 
were certainly not small, if we may rely on Machaeracanthus 
as an indication of their armour. Coccosteus, too, still lingered 
on and probably the future will reveal to us others of greater 
and less size, the companions of these in Corniferous Ohio, es- 
pecially from that ichthyic cemetery, the bone-bed. 
On a general review of the vertebrate fauna of the Corni- 
ferous the palaeontologist is disposed to assign to it an age 
somewhat less than that of the lower Old Red sandstone of 
England and other parts of Europe, in consequence of the ab- 
sence of the cephalaspidian forms, which so strongly character- 
ize the lowest Devonian horizon on that continent. With the 
two exceptions noted above, none of these have yet been report- 
ed from the strata of Appalachia. But they are known in the 
northeast, where the Canadian geologists have found them in 
the lower Devonian beds at Campbellton. And tneir presence 
in the Upper Silurian of Pennsylvania may be regarded as an 
indication of freer connection between the European and Amer- 
ican areas in earlier times than in the Corniferous. 
The Corniferous-Hamilton— the equivalent of the eastern 
Hamilton — supplies many of the above forms and carries the 
record over the almost total blank exhibited by the former in 
the east where scarcely any ichthyic fossils have yet been found. 
A Coccosteus ? reported by me from the Hamilton sandstone of 
Perry county, of Pa.,* and a Dinichthys found by Dr. Lincoln 
in the Marcellus shale at Geneva, N. Y., constitute almost our 
whole list of Hamilton fish-fossils from the eastern strata.! 
Apparently the fishes of the Corniferous were tenants of the 
open sea and the clear water, where dwelt the coral polyps and 
where the deposits were limestone. We may almost venture 
* American Geologist, March, 1893. 
t Op.cit., Nov., 1893. 
