THE FAMILIES AND GENERA OF BATS. 169 



Characters. — Dental formula : 



- 2 3. 1. - - 3 4 5 (i - ,2-2 1-1 2-2 2 - 2_ 



1 2 -. 1. - 2 - i 5 6 - '' 2 " - 2' '' 1 - vP m 2^2' m 2 -~2 -28 - 



Upper incisors small, subequal, forming a discontinuous, nearly 

 straight row between canines. Inner tooth larger than outer, its 

 crown narrow, longer than high, the cutting edge rising to a point 

 at middle and slightly emarginate on each side, the emarginations 

 sometimes deep enough to make the crown appear tricuspid. Outer 

 incisor with indistinct cusp at outer edge. Lower incisors equal, 

 low, closely crowded in straight line between canines, their crowns 

 transversely grooved. Upper canines flattened antero-posteriorly, 

 the anterior surface concave just above base, the tip distinctly bent 

 backward; posterior surface convex below, concave above; cutting 

 edges well developed. Lower canines similar, but smaller, the front 

 surface slightly and evenly convex from base to tip, the posterior 

 surface concave. Premolars not very different from lower canines, 

 the mandibular teeth almost exactly similar, except that their bases 

 are longer and their shafts not as high. Posterior upper premolar 

 with distinct though small supplemental cusp on posterior cutting 

 edge, and with concave surface of crown noticeably roughened. 

 Molars, both upper and lower, of the ordinary Stenodermine type, 

 but with its peculiarities carried to the extreme ; m x almost twice 

 as broad as long; hypocone, protocone, and paracone directly in line 

 with each other and nearly equidistant, all well developed; meta- 

 cone long and low, a small supplemental cusp between paracone 

 and metacone; outer cingulum obsolete, the inner well developed 

 and extending to point of paracone ; m - more than half as large as 

 m 1 , the four normal cusps present, but the two outer very short, 

 almost terete, and the metacone considerably displaced inward by 

 the abrupt rounding off of postero-external angle of crown. Crush- 

 ing surfaces of both teeth finely and closely wrinkled. Lower 

 molars not specially modified, each with the usual two inner and 

 two outer cusps and a flatfish, very wide, finely corrugated crushing 

 surface. Anterior molar broadest posteriorly, posterior broadest 

 anteriorly ; m „ with about two-thirds the crown area of m 1 (Plate 

 VI, fig. 2). Skull with high, rounded, narrow braincase, and prac- 

 tically no rostrum, the nares being at level of anterior zygomatic 

 root and opening directly above incisors. Sagittal crest distinct, 

 extending over entire brain case. Palate very wide and short, its 

 length only about half its width. Posteriorly it is angular-emar- 

 ginate by forward extension of interpterygoid space. Pterygoids 

 simple, rather strongly diverging posteriorly, with distinct, outward- 

 curved hamular processes. Between pterygoids and audital bulla' 

 lies a broad, flat space, traversed by a median longitudinal ridge. 



