VESPERUGO. 19 
Fam. I. VESPERTILIONIDA. 
1. VESPERUGO. 
Vesperugo, Keyserling u. Blasius, Arch. f. Naturg. v. i. p. 312 (1889). 
Scotophilus auctt. (nec Leach)*. 
The members of the widely distributed family Vespertilionide are characterized by 
their widely separated intermaxillaries, simple nostrils, and well-developed tragus, com- 
bined with a lengthened tail which reaches to the margin of the interfemoral membrane. 
Of the four genera represented in the Central-American fauna, the first, Vesperugo, 
may be recognized by the broad flattened head, by the short subtriangular ear of 
which the outer margin has its origin near the angle of the mouth, by the small inward- 
curved tragus, the short legs, and usually by the presence of a small posterior lobe 
attached to the calcaneum. | 
The range of Vesperugo is co-extensive with that of the family, including all the 
zoographical regions and most of the subregions. ‘The species are both very numerous 
and often very variable in their characters; for ‘specimens of the same species, even 
from the same locality,” says Mr. Dobson, “ occasionally present differences which lead 
to their being regarded as distinct species.” The Bats of this genus, and, indeed, of the 
whole family, are consequently very difficult to diagnose, especially in a few words; but 
the four Central-American species may be distinguished by the following characters :— 
1. V. serotinus. Incisors?;°. Tragus broadest below the middle of its outer 
margin ; last two caudal vertebree free. Forearm 2”15. Fur varying from 
dull brown to brownish-buff, paler beneath. 
2. V. propinquus. Incisors ?;?. Tragus broadest about the middle of its outer 
margin ; ear-conch thickened at its inner edge. Forearm 160. Fur rufous 
above, paler beneath. 
3. V. albigularis. Incisors ?;?. Outer margin of ear-conch rising under the jaw 
and separated from ae of mouth by a wart. Forearm 169. Fur dark 
brown; chin, throat, and posterior margin of membrane white. 
4, V. parvulus. Incisors+:!. Tragus long, pointed ; postcalcaneal lobe well de- 
veloped. Forearm 1"15. Fur brownish-yellow, paler beneath. — 
2 
* The type of Scotophilus of Leach (Trans. Linn. Soc. xiii. 1822, p. 71) was an immature Bat in the British 
Museum, probably identical with Nycticejus temmincki, Horsfield; and his name has been very properly re- 
stricted by Professor Peters and Mr. Dobson to the Old-World species formerly included in the genus Vycticejus 
(cf. Monatsb. Ak. Berl. 1866, p. 679; P.Z.S. 1875, p. 368). 
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