26 
The discovery of fish-remains in the Upper Silurian of this 
country, has been repeatedly announced, but never as yet 
confirmed. In the Paleontology of New York, (Vol. II, 
page 320 and plate 71,) Prof. Hall has described and figured 
what he regarded as the fin-spine of a fish from the Clinton 
group, giving it the name of Onchus Deweyt. Onchus is a 
genus of sharks from the Ludlow rocks of Great Britain, (the 
equivalent of our Lower Helderberg series), described in like 
manner from spines; but this fossil has not been accepted as 
a fish relic, but is by general consent regarded as the spine of 
a crustacean. 
Hugh Miller, (Footprints of the Creator, p. 148) has figured 
a fin-spine, “from the Onondaga Salt-group.” He was here 
misled by a confusion of names; the specimen having come 
from the Onondaga Limestone, a local New York division of 
the Corniferous, and being in fact a spine of the Devonian 
genus Macheracanthus. 
All the evidence bearing on the first appearance of fishes 
is, however, but negative; and as the upper part of the 
Upper Silurian series abroad has been proved to contain 
quite an ichthyic fauna, it is possible, at least, that 
something similar may at any time be discovered here. It is 
worth while to observe that the Silurian crustacea seem to 
have been provided with means of defence against enemies 
of some kind. Although they were highly ornamented, yet 
there is more than ornamentation implied in the spiny and 
bristling character of quite a number of Lower Silurian tri- 
lobites, as well as in their power of rolling themselves into a 
ball. Acidaspis, for instance, was a perfect hedgehog in its 
armament. It is probable, however, that the defences of the 
Silurian crustaceans were to protect them against the 
cephalopods, such as Orthoceras, which was abundant and 
attained great size. Fishes, if they existed at all on this 
continent, in that age, were few and small. ) 
When we pass to the Devonian rocks, however, all is 
changed. Then appears a rich development of ichthyic life, 
in many varied and remarkable forms. Especially noticeable 
is the elaborate armament, offensive and defensive, of the 
