432 



EXTINCT MAMMALIA OF NORTH AMERICA. 



part it presents a deep median groove, closed by the apposition of the maxillaries, 

 and this groove is separated only by a narrow ridge from the alveoli. The sides of 

 the maxillaries are slightly concave longitudinally, convex transversely. The inter- 

 maxillaries are broken away, leaving a wide, angular gutter between the remains of 

 the maxillaries. 



Delphinus 



-? 



Oetacean, Wyman : Am. Jour. Sc. 1850, X, 231, Figs. 7a, 7b, 7c. 

 Squalodou mento, iu part of Cope : Proc. Ac. Nat. Sc. 1867, 152. 



In a Notice of Remains of Vertebrated Animals found at Richmond, Virginia, Prof. 

 Wyman describes the fragment of a jaw and several isolated teeth which he regards 

 as belonging to an animal of the same species, a Cetacean resembling in the corres- 

 ponding parts the genus Delphinus. 



Of the two teeth, represented in figures 75, 7c, accompanying the notice, which 

 Prof. Wyman has submitted to my inspection, that of 76 evidently belongs to an 

 animal of the Dolphin family. 



The crown is conical, compressed fore and aft, curved inwardly, smooth, and fur- 

 nished in front and behind with an indistinct linear ridge defining the inner and outer 

 parts. The fang is somewhat quadrate and gibbous, and much thickened by cemen- 

 tum, which is partly broken away in the specimen. From the oval obtuse bottom 

 of the fang a circular aperture communicates with the pulp cavity. 



The tooth represented in figure 7c may belong to the posterior part of the same 

 series. It is smaller than the preceding, and has not the crown compressed fore and 

 aft. The fang is fusiform, gibbous, and curved backward. 



The tooth represented in figure la appears to have been lost, so that I have not 

 had an opportunity of inspecting it. It may have belonged to the same animal. 



The measurements of the two teeth represented by figures 76 and 7c are as follow : 



Lengtli of crown. 

 Breadth do. fore and aft, 

 Thicknesss do., 

 Lengtli of fang, . 

 Thickness of fang, 



Three teeth from the miocene of North Carolina bear a resemblance to those just 

 described. One of them nearly repeats the form of that first noticed, but is con- 

 siderably smaller. The others have the same shaped crown as in the second described 

 specimen, but are stouter and longer, though the fangs are not so gibbous. 



Lines. 



Lines. 



. 6 



5 



. 2i 



21 



. 3* 



21 



. 8 



8 



. 4i 



4 



