1870.] ■ ZiiO [Cope. 



quadrangular, with one angle upwards and the extero-inferior side con- 

 vex. This is occasioned by the presence of a third flattened side, besides 

 the two worn faces, at right angles with the interior worn face. It pre- 

 sents a short longitudinal groove, which may be abnormal. Extremity 

 narrowed, sub-round, obtuse. The direction of the outer worn surface is 

 outwards and backwards. 



M. M. 



Total length, 0.0543 



Vertical diameter at base, .0117 



Transverse " " .0075 



" near tip, .006 



The color of the tooth is dark red, and it has not penetrated far into 

 the dentine. On application to a flame, a very faint odor of organic mat- 

 ter may be perceived, and a slight trace of carbon may be detected. The 

 surface is considerably worn, so that it cannot be determined whether 

 there was a coat of enamel originally or not. It was discovered in Staf- 

 ford Co., Virginia, at the same locality from which the molar of the hog 

 above described, was procured. They have both been rolled, and are 

 both of a red color. 



The Thinotherium anmflatum was a small Hippopotamus-like animal, 

 about the size of the wild boar. As it was no doubt like its recent allies, 

 a shore-and-swamp-loving beast, I name it from 0cw the shore, or S-qqiir^, 

 a wild animal. 



The discovery of the Hippopotamus in America, by O. X. Bryan, and 

 the hog, by Dr. Lockwood, is of considerable interest. Neither types 

 have been heretofore known in either extinct or recent condition (except 

 as introduced), and are, therefore, not included in Leidy's recent Synopsis 

 of Fossil Mammalia of North America, in the Journal Acad. Natl. 

 Sciences, Phila. De Castro, in an essay entitled, " De la Existencia de 

 la grandes Mammiferos Fossiles en la Isla de Cuba," Havana, 1865, states 

 that remains of Hippopotamus occur in the Island of Cuba, referring 

 them to an extinct species. Leidy remarks on this,* that they are proba- 

 bly recent, and cites examples of specimens used for making artificial 

 teeth by dentists, having been brought to liim as fossils. 

 MYLIOBATIS, Cuvier. 



MYLIOBATIS GLOTTOIDES, Cope. 



Spec. nov. 



Established on three specimens, one of which presents a series of eight 

 teeth very convex in longitudinal as well as transverse direction. On the 

 median line the teeth are suddenly swollen, forming together a broad obtuse 

 median ridge. The lateral portions on either side are each slightly convex, 

 and thin off to a margin which embraces but a single series of lateral teeth. 

 Each transverse tooth is nearly straight, the extremity slightly and ab- 

 ruptly curved backwards. Each tooth is both wider (longer) and deep- 

 er than in most of the described species. The worn surface forms a sub- 

 triangular concavity. 



* Proce2d. Acatl. Nat. Sci., Phil., 1868, 179. 

 A. P. S. — VOL. XI— 9E 



