68 MOSASAURUS. 
by Prof. Emmons at Elizabethtown, Cape Fear, North Carolina, and described by 
me under the names of Drepanodon impar' and Lesticodus impar.? 
24. A tooth, differing from any other specimens in its soft, chalky consistence and 
ochre color, from near Hanover, Burlington County, New Jersey, contained in the 
museum of the Academy. The crown is worn and broken at its apex, and when 
perfect appears to have been near two inches long. It is elliptical in section, and 
not quite equally divided by the usual ridges into two surfaces, 
No. 26. which exhibit an obscure disposition to subdivide into planes. 
The antero-posterior diameter of the base of the crown is 
fourteen lines, the transverse diameter ten lines. ‘The ac- 
companying outline, No. 26, represents a section at the base 
of the crown, of which the inner curve is twenty-one lines, 
the outer seventeen, lines. 
The fang is two inches and a half long, nearly two inches in breajlth from before 
backward, and one inch and a quarter transversely. It is abqut one-third excavated 
at the bottom and postero-internally for a successional tooth, but the excavation 
does not expose the pulp cavity, except through two narrow vasculo-neural canals 
of the fang. 
25. A much mutilated tooth, from Monmouth County, New Jersey, presented to 
the Academy of Natural Sciences by Charles C. Abbott. The crown nearly 
resembling that last described, both in size and form, has the remains of the inner 
surface rather more distinctly subdivided into planes, and is slightly striated at the 
base. The outer surface, nearly all destroyed, in the small remaining portion gives 
evidence of its also having been more distinctly subdivided than in the former 
specimen. The antero-posterior diameter of the base of the crown is thirteen 
lines, and its transverse diameter has been about nine lines. 
The fang, preserved entire, unexcavated, and without evidence of having been 
coossified with its alveolus, is particularly remarkable for its small size, in relation 
with the crown, in comparison with other specimens. It measures an inch and a 
half long, is nearly as broad, being seventeen lines antero-posteriorly, and is ten 
lines transversely. 
The interior pulp cavity of the tooth appears as a large compressed fusiform 
receptacle, extending as nearly to the end of the fang as it does to the summit of 
the crown. 
26. A mutilated tooth, from Monmouth County, New Jersey, presented to the 
Academy of Natural Sciences by Dr. J. H. Slack. The crown had nearly the same 
form as that of the preceding specimen, but it is smaller, and the surfaces are 
distinctly subdivided into planes. 'The antero-posterior diameter of the base of the 
crown is 11 lines, the transverse diameter seven lines and three-quarters. 
27. Two shed crowns of teeth, nearly alike, one from St. George’s, New Castle 
County, Delaware, presented to the Academy of Natural Sciences by T. A. Conrad; 
1 Proce. Acad. Nat, Sci. 1856, VIII, 255; Report of the North Carolina Geological Survey, 1858, 
224, Figs. 45, 46. 
2 Proc. Amer. Philos. Soc., 1859, VII, 10. 
