BY C. W. 1>E VIS. 95 



rim forming a rather distinct talon with a rudimentary Hnk rising 

 upon the lobe. Incumbent folds on the face of the lobes well 

 marked. Ledge of upper premolar distinct and continuous fore 

 and aft, a subsidiar}^ cusp on the hinder end of the outer side of 

 the crowm. Size large, a])out equal to that of S. goliah. 



Dimensions. 



Mandibular. — The first three true molars are together 56*0 in 

 length; the premolar 18-0. The width of m.-"^ is 18-0. The 

 thickness of the mandible is not less than 27 '5. 



Maxillary. — The premolar is 21'0 x 14*1 in one example; 19 '6 

 X 15-0 in other. 



Form of teeth. 



Mandibular. — P.* (PL xv. fig. 3). Elongate-ovate, diameters 

 18-0 X 8 '2, structurally similar to that of >S'. goliah, but differing 

 from it in form and size, and in the latter character agreeing with 

 the upper premolar (10214 the type of the species). On the 

 inner surface of the crown of this tooth are six distinct ribs, five 

 of which form denticulations on the crest; these are not present 

 in S. goliah. 



Molars. — (PL XV. fig. 1). The lobes of the molars are remark- 

 ably thin and flat or even a little concave on the posterior surface 

 their crests perfectly straight and^ their angles sharp. The 

 incumbent folds are much the more numerous on the anterior 

 lobes, the outermost of them being the largest and forming by its 

 repetition a regular series in the line of the teeth. The hinder 

 surfaces of the lobes are faintly sculptured into numerous obscure 

 folds. In size the molars agree with those of S. goliah. 



Maxillary. — P* (PL xv. fig. 2). Elongate-ovate with the angles 

 rounded and tumid; diameters 22-0 x 15*0. Crest central; 

 mesial region of outer side of crown with a few vertical ribs. 

 Inner side of crown a rectangular ledge from end to end connected 

 with the lobe by numerous transverse ribs. To the end of the 

 outer side of the crown is attached, as in the deciduous tooth of 



