FISHES OF THE CARBONIFERCUS SYSTEM. 149 
DinicutTHys minor, Newb. 
Plate VIII, Figs. 1-8. 
Dinichthys minor, Newb.; Annals N. Y. Acad. Sci., vol. 1, 1879, p. 191. 
The dorsal plate of this species is about eight inches long, of which 
little more than half is occupied by the dorsal shield, the remainder being 
made up by the long and slender neck, which forms the extension of the crest 
of the inferior side. The plate itself is shield-shaped, terminating anteri- 
orly in an acute point, posteriorly in an obtuse one. The sides, irregularly 
rounded, run to a feather-edge, which was probably buried in the integu- 
ment. The superior surface is marked by several obtuse, longitudinal strie, 
and by a peculiar transverse, crape-like wrinkling. Near the anterior bor- 
der are some corrugations which look like places of muscular or cutaneous 
attachment, and the whole aspect of the upper surface is more that of a 
buried than a superficial bone. The under surface is uniformly excavated 
and arched transversely on either side of the low and sharp central crest. 
This crest is prolonged into a narrow, neck-like process, which projects 
backward and downward from the posterior margin of the shield, and is 
excavated in a broad furrow along its upper surface. 
The supra-occipital bone, which seems to have readily disarticulated, 
is two and one-fourth inches long by three inches wide, rounded behind, 
with a low point at the center of the margin; anterior portion wedge-shaped, 
truncated. The upper surface is marked by several broad shallow furrows, 
separated by low, obtuse, radiating ridges, the whole marked with the charac- 
teristic crape-like wrinkling. The under surface shows a backward slope with 
a prominent ridge, which forms the terminal point. Anterior to this slope is 
a semi-elliptical excavation bordered posteriorly by a relatively sharp ridge, 
the anterior margin of the slope mentioned above. In the bottom of this 
excavation are two shallow pits separated by a low ridge, as in the other 
species of Dinichthys and the allied genera. The anterior portion of the 
inferior surface slopes rapidly upward. The dentition is not certainly 
known, but an imperfect jaw found with the specimens described above and 
corresponding in size is some four inches in length, and consists of an ex- 
posed and a buried portion as in D. Terrelli. The posterior extremity is 
