FISHES OF THE CARBONIFEROUS SYSTEM 103 
mung, Waverly, and Carboniferous limestones occur teeth that cannot be 
distinguished from the equally abundant and wide-spread Helodus gibberulus 
of the British Islands. 
CLADODUS CARINATUS, 0. sp. 
In the collections made by Messrs. Beecher and Randall from the fish 
beds at Warren, Pa., are numerous teeth and impressions of teeth of Clado- 
dus. Nearly all these, however, are too imperfect for aceurate description. 
They apparently represent several species, but they are very much decom- 
posed. One small species, however, collected by Mr. Beecher, is better 
preserved, and is so peculiar, that it deserves special notice. It is less than 
half an inch in breadth and height, the base narrow, and bearing one central 
and four lateral cones, the exterior pair larger than the intermediate ones, 
but all much lower than the central denticle. This carries the characteristic 
feature of the species in four relatively strong carinations on the flattened 
surface. Of these the outer two are short and low, the inner two rela- 
tively stronger than in any other species known to me. 
Ciapopus KeEpuert, n. sp. 
Plate XLIV, Figs. 1,2; Plate XLV. 
Fishes three to six feet long by six to eight inches wide at the pectoral 
fins; body long-fusiform, as broad as high; upper surface covered with 
shagreen, composed of fine, apparently plain, tubercles; under surface near 
head transversely striated; jaws partially ossified; teeth very numerous, 
half an inch in height and breadth, consisting of one striated median cone 
with one lateral denticle on either side; pectoral fins oblong, conical, 
rounded at the extremity, five inches wide by eight to ten inches long, 
traversed by about twenty strong unarticulated, ossified rays, simple below, 
forked above; eyes large, capsules bony. 
We have in these fishes another illustration of the unusual amount of 
ossification in the skeletons of certain Carboniferous sharks to which I have 
referred elsewhere, viz, complete ossification of the rays supporting the 
lower lobe of the tail in the large selachian found by Mr. Patterson in the 
