198 BULLETIN 57, UNITED STATES NATIONAL MUSEUM. 
Cheek teeth less than 77 — 
6-6 
Upper premolars 2-2. 
Upper incisors 1-1 ; metacarpal of third, fourth, and fifth fingers 
successively much shortened Lasiurus , p. 221. 
Upper incisors 2-2 ; metacarpal of third, fourth, and fifth fingers 
about equal in length. 
Lower premolars 3-3. 
Audital bullse not specially enlarged ; rostrum broad, con- 
cave on each side above ; ear shorter than head. 
Lasionycteris, p. 203. 
Audital bullpe much enlarged ; rostrum narrow, evenly con- 
vex above ; ear much longer than head. 
Anterior edge of orbit distinctly ridged ; nostrils hot 
overhung by glandular outgrowths from side of 
muzzle Plecotus, p. 224. 
Anterior edge of orbit smoothly rounded ; nostrils 
overhung by conspicuous glandular outgrowth from 
side of muzzle Corynorhinus , p. 225. 
Lower premolars 2-2. 
Lower carmine small, its tip unequally bifid; diameter of 
audital bulla equal to length of tooth row, exclusive of 
incisors; ear much longer than head Euderma, p. 225. 
Lower canine well developed, its tip not bifid ; diameter of 
audital bulla much less than length of tooth row ; ear 
not specially elongated. 
Braincase conspicuously deepened, its depth including 
audital bullae nearly equal to its width. 
Chalinolobus, p. 219. 
Braincase normal, its depth including audital bullae 
much less than its width. 
Outer upper incisor not extending beyond cingu- 
lum of inner. 
Outer upper incisor distinctly cuspidate. 
Scotozous, p. 206. 
Outer upper incisor with flat crown. 
Ia., p. 206. 
Outer upper incisor extending distinctly beyond 
cingulum of inner. 
Fifth finger only a little longer than meta- 
carpal of fourth and third. 
Pterygistes, p. 207. 
Fifth finger longer than metacarpal and first 
phalanx of fourth and third. 
Upper surface of rostrum concave ; ears 
joined Barbastella, p. 223. 
Upper surface of rostrum convex ; ears 
separate. 
Outer upper incisor normal in posi- 
tion, its concavity directed back- 
ward Pipistrellus, p. 204. 
Outer upper incisor pushed outward 
from its normal position, the con- 
cavity directed outward. 
.Glischropus, p. 205. 
