Bats 
271 
q'" Upper premolars, 2. Skull large with very broad 
rostrum, and, in adult, with conspicuous sagittal 
crest; back of interfemoral membrane wholly- 
naked except for a sprinkling of hairs on basal 
fourth; color brown; size quite large, length, 4.5 ; 
forearm, 1.7 5-1. 9, Eptesicus, p. 278 
b". Upper incisors, 2; upper premolars, 4. Dorsal surface 
of interfemoral membrane furred to nearly- 
extreme edge ; size large, length, 4.3-5.5 ; forearm, 
1.6-2.0 ; mammae, 4. Nycteris, p. 280 
b'. Ears very large, and joined at inner margin; length about 
4; forearm, 1.65. Corynorhinus, p. 282 
b. Lower incisors, 4. Ears quite large and wide apart at base; 
color pale; size moderately large, length, 4.3; 
forearm, 2. Antrozous, p. 283 
B. Posterior third or more of tail projecting beyond and free 
from interfemoral membrane {Molossidcs). 
Nyctinomus, p. 285 
Family VESPERTILIONID^ 
These are insectivorous bats with the nostrils placed at the 
extremity of the muzzle and opening by simple circular 
or crescentic apertures, with moderate-sized ears, usually 
separated, with well-developed tragi; legs short, tail long, 
contained in and produced to the hinder margin of the inter- 
femoral membrane, with only the extreme tip occasionally 
projecting. 
Incisors on either side, upper ones small, separated 
by a wide space in the middle line, usually close to the 
canines; upper premolars one to three in number, when the 
latter the anterior tooth is usually small and often outside 
or inside the regular tooth row. This family is found 
nearly all over the world and contains by far the greatest 
number of species and individuals in the order. 
Genus MYOTIS (Grk. mus, mouse + otiSy ear, mouse-eared) 
Myotis Kaup, Skizzirte Entw.-Gesch. ii. Naturl. Syst. d. Eiirop. 
Thierw., i., p. 106 (myotis) (1829). Type, Vespertilio myotis 
Bechstein. 
Revision, Miller, .V. A. Fauna, No. 13 (1897). 
