146 BULLETIN" 57, UNITED STATES NATIONAL MUSEUM. 



but distinct protocone forming entire very narrow inner side of 

 tooth and isolated from outer cusps by a distinct median depression. 

 Paracone and metacone well developed though narrow; parastyle 

 and metastyle small; mesostyle absent. The cones and styles are 

 connected by a commissure which forms a sinuous cutting edge but 

 no W pattern. Third upper molar about half as large as first or 

 second, consisting of a short, wide parastyle, a low paracone from 

 which a slight commissure extends backward to edge of tooth. First 

 and second lower molars with all the cusps indicated but only the 

 protoconid and metaconid well developed. Third lower molar with 

 no entoconid. Skull rather heavily built. Rostrum about two-thirds 

 as long as brain case, the lachrymal region slightly swollen; lach- 

 rymal breadth equal to distance from orbit to gnathion. Braincase 

 rising conspicuously though not abruptly above forehead. Zygomata 

 incomplete. Basisphenoid pits broad and shallow. Audital bulla? 

 small, covering less than half surface of cochleae, their diameter 

 slightly less than width of basioccipital. Ears small, separate. Tail 

 short, extending to middle of moderately wide interfemoral mem- 

 brane, its length about half that of femur. 



Species examined. — I have examined all the known members of 

 this genus. 



Genus RHINOPHYLLA Peters. 



1865. Rhinophylla Peters, Monatsber. k. preuss. Akad. Wissenscn., Berlin, 



p. 355. 

 1878. Rhinophylla Dobson, Catal. Chiropt. Brit. Mus., p. 495. 



Type-species. — Rhinophylla pumilio Peters. 



Geographic distribution. — Tropical South America. 



Number of forms. — Only the type species is at present known. 



Characters. — Like Hemiderma, but tail absent, skull with much 

 broader rostrum and lower brain case, and teeth more highly modi- 

 fied, though of the same number. Upper incisors like those of 

 Hemiderma, except that the outer is relatively larger, its crown 

 distinctly pointed, and inner is bilobed on cutting edge, the lobes 

 nearly equal in size. Premolars as in Hemiderma, but pm 3 very much 

 smaller than pm 4 . Molars with the Hemidermine peculiarities 

 much exaggerated, the inner portion of m 1 and m 2 so greatly 

 reduced that there is practically no protocone; parastyle and 

 metastyle distinct, but low; paracone and metacone low and very 

 narrow, producing a faintly two-lobed cutting edge, the posterior 

 lobe of which (metacone) is distinctly higher than the anterior. A 

 wavy commissure extends from parastyle to paracone and thence to 

 metacone and metastyle. Onm'a faint trace of the inner commis- 

 sures may be detected, extending from the two main cusps downward 



