68 



however, demonstrated that they were not saurian but cetacean 

 bones, and he gave to them the name of Zeiiglodon ceii, the 

 generic name being derived from the peculiar form of the teeth, 

 which consist of two roots yoked together by the crown. The 

 crowns of the teeth which fell under the observation of Prof. 

 Owen, were imperfect, and it is therefore impossible to say how 

 far they are identical with those of the animal of which we have 

 been speaking. The latter do, however, present a complete re- 

 semblance to the teeth described and figured by Prof. Gibbes, of 

 Columbia, S. C, in the Proceedings of the Academy of Natural 

 Sciences, for June, 1845, under the name of Dorudon serratus. 

 These last have been compared by Prof. G. with those of a 

 Zeuglodon at Albany, in the State Cabinet, and in speaking of 

 them, he says, " I was much struck with the similarity in their 

 general characters with those of Dorudon." " The teeth of the 

 Zeuglodon are solid, of a dense structure and very strong, and 

 resembling those of the cetacea ; while the liollowness of those of 

 the Borudon approximate it to the saurians." Other differences 

 of less importance are referred to by Prof. G. The Hydrarclws 

 and Dorudon are unquestionably members of the same genus ; 

 and if the bones at Albany are those of the Zeuglodon^ it is 

 highly probable that it is to this genus that the preceding must be 

 referred. The character of " hollowness" does not appear to be 

 sufficient to establish generic distinctions, unless it can be shown 

 that it is not the result of imperfect development, or that it is not 

 the consequence of the ossification of the teeth being incom- 

 plete. We have not, as yet, a perfect series of the teeth of the 

 Zeuglodon^ and are therefore ignorant what are the varieties of 

 form which such a series would present in different parts of the 

 same jaw. The figures and descriptions of Prof. Gibbes are of 

 great value, being the only perfect representations of individual 

 teeth which have as yet appeared, and it is to be hoped that his 

 future researches may enable him to complete the osteological 

 description of these interesting remains. 



A connmunication vi^as received from Lewis R. Gibbes, 

 M. D., of Charleston, S. C, enclosing a Catalogue of the 

 species of Crustaceans contained in the Cabinet of this So- 

 ciety, as recently examined and determined by him. Viz. 



