144 BULLETIN 57, UNITED STATES NATIONAL MUSEUM. 
As in Leptonycteris , m 2 has the appearance of a third molar. Lower 
molars with the cusps all reduced in size, the metaconid largest. 
Zygomata incomplete. Tail distinct, about half as long as femur, 
extending scarcely to middle of broad inter femoral membrane. 
Species examined. — Liclionycteris obscura Thomas. 
Remarks.— This genus appears to be most nearly related to Lep- 
tonycteris , with which it agrees in the very peculiar * formula of the 
cheek teeth. It is, however, even more aberrant, having lost the 
lower incisors, and almost lost the W pattern of the upper molars. 
SiibfamLly HEMIDERMIN^]. 
1838. Phyllostomina (part) Gray, Mag. Zool. and Bot., II, p. 486, Decem- 
. ber, 1838. 
1855. Glossophagina (part) Gervais, Exped. du Comte de Castelnau, Zool., 
Mamm., p. 40. 
1865. Vampyri (part) Peters, Monatsber. k. preuss. Akad. Wissensck., 
' Berlin, p. 256. 
1866. V ampyrina (part) Gray, Proc. Zool. Soc. London, p. 113. 
1875. Vampyri (part) Dobson, Ann. and Mag. Nat. Hist., 4th ser., XVI, 
p. 350, November, 1875. 
1878. Vampyri (part) Dobson, Catal. Chiropt. Brit. Mus., p. 458. 
1891. PhyllostomatincB (part, Vampyrine division, part) Flower and 
Lydekker, Mammals living and extinct, p. 672. 
1892. Phyllostomata (part) Winge, Jordfundne og nulevende Flagermus 
(Chiroptera) fra Lagoa Santa, Minas Geraes, Brasilien, p. 24. 
Geographic distribution. — Warmer parts of America north to 
southern Mexico and in the West Indies to Jamaica. 
Characters. — Teeth abnormal. First and second upper molars 
with protocone greatly reduced ( Hemiderma ) or obsolete ( Rhino - 
phylla) , occupying entire very narrow inner edge of tooth ; paracone 
and metacone large, trenchant; parastyle and metastyle present, 
though small; mesostyle absent; an angular-concave commissure 
nearly in line with main axis of toothrow connects the outer cones 
and styles, but without forming any trace of a W pattern. Third 
upper molar never half as large as first or second, either a practically 
structureless remnant or at most with two low cusps, apparently the 
paracone and parastyle. Lower molars with protoconid (in Ilemi- 
derma the hypoconid also) well developed and forming with its 
commissures a median longitudinal cutting ridge, close to the middle 
of which the rather small metaconid may be situated. (In Rhino- 
phylla the metaconid is absent and the molars closely resemble the 
premolars in form.) Paraconid and entoconicl small or absent. 
Rostrum, noseleaf, and tongue normal. 
History .— Except that Gervais associated the genus Hemiderma 
with the Glossophagine bats in 1855, the Hemiderminse have been 
almost universally referred without special comment to the Phyl- 
