THE CARBONIFEROUS SYSTEM. 179 
In the report of Mr. Meek, which forms part of the volume on Paleon- 
tology that accompanies this, our Carboniferous mollusks are fully de- 
scribed, and, therefore, no further reference to them is required here. 
Of articulates we have found very few. Several crustaceans are de- 
scribed in Mr. Meek’s report, and I obtained from the shales over the 
lower coal in Summit county fragments of a single insect. This was a 
kind of cricket, of which a description, prepared by Mr. 8. H. Scudder, 
will be found in Part II. of this volume. 3 
By far the most interesting animal remains discovered in our Coal 
Measures are fishes and amphibians. Of these, the fishes were nearly 
all described in the volume already published. Since that appeared 
some interesting additions have been made to our Carboniferous fish 
fauna, of which the most important is a species of Ctenodus, a genus fre- 
quently met with in the Coal Measures of Europe, but not before found 
in the United States. 
The amphibians of the Coal Measures are more fully represented in 
our collections than in all the material which has gathered elsewhere. 
Prof. Cope has already described twenty-six species of aquatic salaman- 
ders from the specimens obtained from the cannel underlying Coal No. 6 
at Linton. These are figured and described in the Paleontological vol- 
ume that accompanies this. 
During the past summer I have procured several additional new spe- 
cies from this famous locality, and among others a well-marked Kerater- 
peton, a genus first described by Prof. Huxley from specimens obtained 
in the Coal Measures of County Kilkenny, Ireland. The species found 
here is distinct from that of Prof. Huxley, but it is closely allied to it, 
and is specially interesting as adding another to the list of vertebrate 
genera common to the Coal, Measure fauna of America and Europe. 
The large number of species of fishes and amphibians (about fifty) 
found in one single coal mine at Linton indicates that the vertebrate 
fauna of the Coal Measures was much richer than has heretofore been 
supposed. The cannel coal of this locality was undoubtedly deposited 
in a lagoon of open water in the marsh where Coal No. 6 was formed. 
How extensive this lagoon was, we have not as yet learned; but all the 
fossils found there have been taken from an area a few hundred feet in 
diameter. We have probably now obtained representatives of most of 
the fishes and salamanders that inhabited this body of water, but cer- 
tainly not all, for every considerable collection made there has contained 
something new; and the fauna of the epoch in which this deposit was 
made must certainly have been very varied, since from this one spot 
