1222 Note on some Fossil Fishes recently discovered (December, 
in this slow manner, but civilized man everywhere tends to a 
close conformity in size, as he also does in conditions of exist- 
ence. Thus any future change in the average size of man must 
be of very slow evolution. Its direction will probably be towards 
greater bulk. 
A’ 
e 
PRELIMINARY NOTE ON SOME FOSSIL FISHES 
RECENTLY DISCOVERED IN THE SILURIAN 
i ROCKS OF NORTH AMERICA. 
BY PROFESSOR E. W. CLAYPOLE. 
I. 
HE lowest Old Red Sandstone of Scotland, the argillaceous 
slates of Cornwall and the calcareo-argillaceous beds of 
Ludlow in England, have furnished the most ancient fossils yet 
published which can be attributed to ‘the class of fish. The first 
and second of these horizons are included in the Devonian sys- 
tem, the third, which is also the most ancient, forms the upper 
part of the Silurian. ; 
Except two species of Onchus (0. murchisoni and O. tenuisir- 
atus) all these fossils are referred to the abnormal family of 
Cephalaspids—a family so abnormal that some zoologists have 
_ seriously doubted if its members were really entitled to the name 
of fishes. But evidence recently obtained has, in the opinion of 
those who have specially studied them, Professors Huxley and 
Lankester, satisfactorily settled the question in their favor, and 
they are now, with general consent, retained among the 
brates, of which they form the most ancient type hitherto recog- 
nized, 
Fossil fish have been reported from rocks called Silurian 
Bohemia and in Russia, but the genera and species present 
aspect so decidedly Devonian, judging by the English strata, that 
it is not easy to correlate the two. Asterolepis, Gompholep®, 
Coccosteus and Ctenacanthus can scarcely be paralleled with the 
more primitive types of the English Ludlow above alluded to. 
No species of fish has yet been published from the wee 
rocks of America, or even from the Lowest Devoniale = 
most ancient fossils of this class which the western continent Ti 
yielded have been found in the Corniferous limestone of = 
and the beds at Campbellton near Gaspé in Canada. Of i 
latter is probably rather the older of the two, as oR 
in 
