EXTINCT MAMMALIA OF NORTH AMERICA. 419 



ter at base. The fang has been about two and a quarter inches long, with its swollen 

 part four and a half lines in diameter. 



Figure 16, of the same plate, represents the greater portion of a more anterior, 

 somewhat larger, and a nearly straight tooth. In its perfect condition it has approxi- 

 mated four inches in length, and in transverse section in any position appears to be 

 of almost uniform diameter. The enamel of the base of the crown, though fissured 

 in the specimen, appears smooth, but it exhibits portions of the linear acute ridges 

 defining two surfaces. 



Figure 17 represents the greater portion of tlie crown of a tooth of more robust 

 proportions than in the preceding. It is long, straight, conical, and invested through- 

 out with enamel, which is strongly wrinkled. In its present state, with broken apex 

 and base, it is twenty lines long. Its diameter above the broken part of the base, 

 between the acute linear ridges separating the two surfaces of the crown, is five 

 lines ; the opposite diameter is four and a half lines. 



Another specimen, with part of the crown nearly like that in the latter specimen, 

 but less wrinkled, and with part of the fang, has had nearly the form of the specimen 

 represented in figure 16. The diameter of the crown at base is five lines by four and 

 a half lines. When perfect, it has been about two inches in length. 



Another specimen, consisting of the crown and part of the fang of the tooth, is 

 intermediate in its proportions and form with that first described and represented in 

 figure 15, and the others. The crown when perfect has measured about sixteen 

 lines long, by four and three and a half lines in diameter at base. The enamel is 

 strongly wrinkled longitudinally. 



All the specimens above described are solid or nearly so, but that represented in 

 figure 17 has a small pit at the base, communicating with the apparently fractured 

 surface, but which really looks like that seen on shed teeth in the position of contact 

 with the successional teeth. I have not been able to determine to my own satisfac- 

 tion whether these teeth belong to one or two distinct species, or to any of those in- 

 dicated by other remains. 



A specimen, also from the Ashley River, represented in figure 9, plate XXIX, per- 

 haps is a canine or anterior premolar of the same animal. The crown is slightly 

 curved, conical, and acute, and has its faintly wrinkled surfaces separated by promi- 

 nent acute borders. The length of the crown is from eleven to twelve lines ; and it 

 is from five to six lines in diameter at base. The fang is hollow, and when perfect 

 has probably approximated two inches in length. The unworn crown and hollow 

 condition of the tooth indicate a young condition. 



I have suspected that these teeth might belong to Squalodon atlanticus, but in com- 

 parison with those in the jaws of S. aniverpiensis, as represented by Van Beneden 

 (Mem. Acad. Roy. Sc. Belgique, XXXV, PI. I), they are much too small in relation 



