68 MOSASAURUS. 



by Prof. Emmons at Elizabethto^vn, Cape Fear, North Carolina, and described by 

 mo under the names of Drepanodon impar^ and Lesticodus imjjar} 



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 qmte equally divided by the usual ridges into two surfaces, 

 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 outlme. 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 brea^lth from before 

 backward, and one inch and a quarter transversely. It is about one-third excavated 

 at the bottom and postero-internally for a successional tooth, but the excavation 

 does not expose the pidp ca%dty, 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; 



• Proc. Acad. Nat. Sci. 1866, VIII, 255 ; Report of the North Carolina Geological Survey, 1858, 

 224, Figs. 45, 46. 

 " Proc. Amer. Philos. Soc, 1859, VII, 10. 



