THE FAMILIES AND GENERA OF BATS. 
211 
Genus HESPEROPTENUS Peters. 
1868. Hesperoptenus Peters, Monatsber. k. preuss. Akad. Wissensch.. Ber 
lin, p. 626 (subgenus of Vesperus). 
1878. Hesperoptenus Dobson, Catal. Ckiropt. Brit. Mus., p. 183 (subgenus 
of Vesperugo ) . 
Type- species.- — Vesperus dorice Peters. 
Geographic distribution. — India and the Malay region. 
Number of forms.— Three species of Hesperoptenus are now 
known: Id. dorice (Peters), Id. tickelli (Blyth), and Id. blanfordi 
Dobson. 
Characters . — Dental formula and general structure of teeth as in 
Eptesicus and V espertilio ; 
but outer upper incisor much 
larger, the area of its base 
more than half that of ca- 
nine, which tooth, in its sim- 
ple, strong shaft and well- 
developed cingulum, it rather 
closely resembles; space be- 
tween inner incisor and ca- 
nine scarcely perceptible, 
barely greater than width of 
cingulum of canine ; outer 
upper incisor closely crowded 
between canine and inner in- 
cisor, forced backward from 
the toothrow, and quite in- 
visible from the front; its 
crown scarcely reaching level 
of cingulum of the two 
neighboring teeth, but with 
area in cross section decid- FlG - 33 
edly more than half that of 
inner incisor, the surface of the crown basin-shaped, with a large, but 
low, central cusp ; other teeth like those of Eptesicus , the third upper 
molar with less than half the crown area of first, but with the meta- 
cone and three commissures distinct though small. Skull (fig. 33) 
broad, the zygomatic breadth nearly equal to upper length in median 
line, but with no special peculiarities in form ; basisphenoid pits 
well developed, though shallow. Externally as in Eptesicus. 
Species examined. — Hesperoptenus tickelli (Blyth). 
Remarks . — It is with some hesitation that I apply the name Hes- 
peroptenus to the genus represented by H. tickelli. I have not seen 
“ Vesperus ” dorice , the type of Hesperoptenus^ and certain features 
in the original description, notably what is said of the position of the 
Hesperoptenus tickelli. Ceylon. No. 123437 
x2. 
