
656 THE AMERICAN NATURALIST. |. [Vor. XXXVI. 
by a shallow, curved depression. D. terrelli has a relatively 
shorter and more massive posterior shaft. As contrasted 
with the compact structure of the dentary portion, which 
has almost the density of enamel, the spatulate shaft is 
finely striato-punctate, and presents more the condition of 
osseous tissue. 
“3. In D. herzeri, the secondary: prominence or denticle 
behind the anterior beak is buttressed on the inner side by a 
prominent angulation or ridge [this is really part of the den- 
ticle, and occurs in other species as well], which sweeps from 
the apex of the denticle downward and backward until it merges 
with the thickened portion of the dentary bone. But in the 

Fic. 1.— Dinichthys pustulosus Eastm, Hamilton limestone; Andalusia, Ill. Right gnathal 
plate. X 4} (nearly). 
present species the entire inner surface is deeply excavated, 
and there is no evidence of a buttress having occurred. 
*4. The present specimen evidently belonged to a species 
of much smaller size than either D. herzeri or D. terrelli, since 
the total length of the mandible is only 20 cm., while both o 
the Ohio forms exceed 60 cm. That it does not pertain to an 
immature individual seems plainly indicated by the marks of 
wear, and general appearance of the bone. 
* The salient features which have been pointed out in the 
foregoing are sufficiently characteristic to warrant the estab- 
lishment of a new species, which we have pleasure in naming 
in honor of Dr. J. S. Newberry, to whom we owe the admirable 
notice of the two first discovered species. In the accompany ing 
figures are shown (4), view of right mandibular ramus from 


