THE FAMILIES AND GENERA OF BATS. 
145 
lostominse. They are now for the first time recognized as a distinct 
subfamily. 
Principal subdivisions . — Only two genera of Hemiderminse have 
been described. 
KEY TO THE GENERA OF HEMIDERMIN^E. 
Lower molars distinctly different in form from premolars ; tail 
present Hemiderma, p. 145. 
Lower molars not distinctly different in form from premolars ; tail 
absent Rhinophylla, p. 146. 
Genus HEMIDERMA Gervais. 
1838. Carollia Gray, Mag. Zool. and Bot., II, p. 488. February, 1838. Not 
Carolia Cantraine, 1837. 
1855. Hemiderma Gervais, Exped. du Comte de Castelnau, Zool., Marnmif., 
p. 43. 
1866. Rhinops Gray, Proc. Zool. Soc., London, p. 115 ( Rhinops minor Gray= 
H emiderma perspicillatum ) . 
1878. Carollia Dobson, Catal. Chiropt. Brit. Mus., p. 495. 
1891. Hemiderma Lydekker in Flower and Lydekker, Mammals, living and 
extinct, p. 674. 
1907. Hemiderma Hahn, Proc. U. S. Nat. Mus., XXXII, p. 108, February 
9, 1907. 
Type-species. — Phyllostoma brevicaudum Wied p= Vespertilio per- 
spicillatus Linnaeus. 
Geographic distribution . — Warmer parts of America north on the 
mainland to southern Mexico, and in the West Indies to Jamaica, i 
Number of forms . — Four forms of Hemiderma are at present recog- 
nized. 
Characters . — Dental formula: (Plates IX and X, fig. 1.) 
-2 8. 1 . — 34567^2-2 „ 1 - 1 ^ 2 - 2 
1 2 -. 1. - 2 - 4 5 6 T % 2 - 2’ C 1-1’ 2-2’ 
m 
3-3 
3-3 
=32. 
Upper incisors strongly contrasted in size, completely filling space 
between canines. Inner incisors large, with projecting, obliquely set 
crowns about as high as long, strongly in contact near apex, the 
cutting edge entire, the outer surface convex, the inner surface slightly 
concave. Outer incisors minute, the rounded, flat crown barely rising 
to height of cingulum of banine. Lower incisors small, forming a 
slightly convex row between canines, the inner tooth larger than the 
outer, its crown somewhat extended backward and distinctly concave 
on inner surface; cutting edge of both teeth entire or slightly 
emarginate. Canines low and strong, simple in form and without 
secondary cusps or noticeable cingula. Premolars rather narrow, with 
well-developed main cusps and cutting edge, but no styles; inner 
surface slightly concave. First and second upper molar with low 
25733— No. 57—07 m 10 
