48 BULLETIN 57, UNITED STATES NATIONAL MUSEUM. 



Characters. — Dental formula : 



-.2 3. 1. -2345-- -2-2 1-1 



1 2 -. 1. -2 3 4 5 6 



2-2' 1-1 



pm 



m 



1-1 



3-3 



3_3' "' 2-2 



=30. 



Teeth without special modifications. Upper incisors in contact 

 with each other, but separated from canine by wide diastema, nearly 

 terete, their crowns slightly flattened antero-posteriorly, the inner 

 tooth of each pair slightly longer than the outer. Lower incisors 

 somewhat flattened laterally, the outer of each pair slightly the 



larger; cutting edge blunt, 

 nearly flat, though divided by 

 a shallow notch into two in- 

 conspicuous lobes. Canines 

 both above and below with a 

 secondary cusp on inner side 

 formed by a slight prolonga- 

 tion of the cingulum and some- 

 what variable in its develop- 

 ment in different species. An- 

 terior upper premolar perma- 

 nent, but scarcely larger than 

 incisor in cross section and so 

 short as barely to penetrate 

 the gum. Its crown is nearly 

 flat, though with a faintly in- 

 dicated antero-external cusp. 

 The corresponding lower tooth 

 is considerably larger, its disk- 

 shaped crown somewhat con- 

 cave except for the minute 

 antero - external cusp. The 

 three suceeding cheek teeth 

 almost exactly resemble each 

 other above and below ; pm z and pm 3 are higher and shorter than the 

 others, and the inner ridge tends to form a blunt cusp opposite base of 

 main cusp ; pm i ,m 1 , pm±, and w^ have the longitudinal furrow well de- 

 ' veloped and bounded on the inner side by a distinct, though low, ridge, 

 and on the outer side by a much higher ridge, which rises anteriorly into 

 a blunt cusp. Their crowns are noticeably longer than broad. The sec- 

 ond lower molar closely resembles the anterior lower premolar, except 

 that it lacks the small antero-internal cusp. The skull (figs. 5, 6) very 

 primitive in form, the ventral profile nearly straight, the dorsal pro- 

 file showing no special peculiarities. Floor of brain case scarcely 



Fig. 5. — Cynopterus sphinx. Adult female. Mad- 

 ras, India. No. 102430. XU. 



