THE FAMILIES AND GENERA OF BATS. 143 



low, flat, rounded crowns. They are almost equally spaced or thrown 

 into two pairs by wider median gap. Upper canine with cingulum 

 obsolete, but represented anteriorly and posteriori}' by short though 

 well-developed cusps, that at posterior base of main shaft the more 

 conspicuous. Lower canine with large cingulum, but no secondary 

 cusps. Premolars long and narrow, with high main cusps and dis- 

 tinct though small styles; anterior lower premolar {pm 2 ) noticeably 

 concave on inner face and slightly convex externally. Molars show- 

 ing no special peculiarities, except that the W pattern in m 1 is 

 distorted by the great length and narrowness of the outer section 

 of the tooth, and to 2 has the form usually characteristic of m s . 

 Inner edge of upper molars broadly convex. Skull of the normal 

 Glossophagine type; zygomata slender, but complete; pterygoids 

 rather short and thick, but not specially modified in form. Tail 

 absent. Interfemoral membrance very narrow. Calcar small, but 

 distinct. 



Species examined. — Leptonycteris tdmjlis (Saussure) and L. 

 curasow Miller. 



Remarks. — The genus Leptonycteris is well characterized by its 

 unique dental formula, though externally it rather closely resembles 

 Anoura and Lonchoglossa. The only other known genus in which 

 the third molar is lacking, Lichonyctei-is, differs very conspicuously in 

 the peculiar form of the upper incisors and in the absence of the 

 lower incisors. 



Genus LICHONYCTERIS Thomas. 



1895. Lichonijctcri.s Thomas, Ann. and Mag. Nat Hist, Otu -sei'., XVI, p. 55, 

 July, 1895. 



Type-species. — Lichonycteris obscura Thomas. 

 Geographic distribution. — Nicaragua and Dutch Guiana. 

 Number of forms. — Only the type species has been described. 

 Characters. — Dental formula: 



-2 3. 1. --3456- . 2-2 1- 1 2-2 2^ 2 

 . 1. - 2 3 4 5 6 - l - 0' c 1 - 1 ,J ""' 3-3' '" 2 - 2 6- 



Upper incisors evenly and widely spaced between canines, their 

 crowns narrow though scarcely trenchant, longer than high, that of 

 inner tooth distinctly emarginate on cutting edge, so that it appears 

 bilobed when viewed from in front, that of outer tooth with sharp, 

 backward- directed cusp near inner e.dge, and a flatfish outer pro- 

 jection. Canines simple, with moderately developed cingula, but 

 no secondary cusps. Premolars rather short and not as narrow as 

 usual, the main cusp well developed except in pm 2 , in which it is 

 obsolete, the styles evident but low. Upper molars with W pattern 

 obsolete owing to the great reduction of the styles and commissures. 



