430 SLOUART WEELER 
however, does not account for the remarkable vertebrate element 
in the Corniferous fauna, as there was nothing in the Niagaran 
fauna which could have given origin to it. It is possible that 
the fishes of the Corniferous fauna originated from some fresh 
water fish fauna which was forced to adapt itself to marine condi- 
tions with the encroachment of the Corniferous sea upon the land. 
During the Corniferous epoch, in the Appalachian province, 
communication was again established over the same route by 
which the Niagaran faunas had found their way into the interior 
basin. 
The relationship of the Corniferous to the Oriskany fauna at 
Cayuga, Ontario, also bears upon the point of entrance of the 
Corniferous fauna into the Appalachian basin. This locality is 
approximately the most northwestern extension of the typical 
Oriskany fauna, and is where it approaches most closely to the 
hypothetical point of entrance of the younger fauna. Here the 
two faunas become intimately commingled, a large number of 
the typical corals, besides other Corniferous types, being associ- 
ated with such characteristic Oriskany species as Spurifer arenosus, 
Hipparionyx proximus, Anoplotheca flabellites, etc., as if it were here 
that the Corniferous fauna first came in contact with the Oriskany. 
It is because of this relationship that the species found in the 
Oriskany fauna only at Cayuga, and not further east, have been 
eliminated from the preceding list of Oriskany species given for 
comparison with the Corniferous fauna, it being assumed that 
they were not members of the true Oriskany fauna, but were 
representatives of the immigrating Corniferous fauna. 
In the Devonian faunas of the Eureka District of Nevada,? 
many representatives of the Corniferous fauna of the Appa- 
lachian province have been recognized. Among these are sev- 
eral of the characteristic corals, although but few of the fish 
remains have been detected. In the Kanab Cafion of northern 
Arizona,? however, which is situated in the same Great Basin 
province, a strongly marked horizon of Devonian fishes has been 
tWatcoTt, Monog. U. S. Geol. Surv., Vol. VIII. 
2 Monog. U.S. Geol. Surv., Vol. VIII, p. 7. 
