210 
BULLETIN 57, UNITED STATES NATIONAL MUSEUM. 
Number of forms. — The genus V espertilio as now restricted con- 
tains only two forms, murinus Linnaeus and superans Thomas. 
Characters— Like Eptesicus , but ear much shortened and broad- 
ened, rostrum flattened above, with a deep concavity on each side 
between nares and lachrymal region; nares very large and extending 
back nearly half way to interorbital constriction, and palatal emar- 
gination extended so far laterally that its width is distinctly greater 
than its depth. 
'Species examined. — V espertilio murinus Linnaeus and V. superans 
Thomas. 
Remarks. — With regard to the necessity for distinguishing V esper- 
tilio generically from Eptesicus , I agree with Mehely. The spe- 
cies nilssoni (=“ borealis ”) , however, shows none of the special 
cranial peculiarities of V espertilio, but is in all respects a typical 
Eptesicus as the genera are here understood. The skull of V esper- 
tilio shows a strong likeness to that of Lasionyeteris / and it is worthy 
of remark that the members of the two genera further resemble each 
other in the rather unusual “ frosted ” coloring of the back. The 
type of Vesperugo ( Marsipolazmus ) albigularis Peters, which I have 
examined in Berlin, is, as suggested by Mehely, merely a specimen of 
V espertilio murinus. 
Genus RHINOPTERUS Miller. 
1906. Rhinopterus Miller, Proc. Biol. Soc. Washington, XIX, p. 85, June 
4, 1906. 
Type-species. — Glauconycteris floweri de Winton. 
Geographic distribution. — Southern Soudan. 
Number of forms. — Only the type species has been thus far dis- 
covered. 
Characters . — Externally like a small Eptesicus , but upper surface 
of forearm, tail, and tibia thickly sprinkled with pointed, horny ex- 
crescences resembling those on edge of ear in some of the Molossidse, 
but larger. Metacarpals as in Eptesicus. Skull differing from that 
of Eptesicus in much greater relative breadth of anterior portion of 
braincase, shorter, lower rostrum, and in the form of the upper 
toothrows as a whole, these being more concave on inner side and more 
convergent anteriorly. Teeth as in Eptesicus. 
Type-species. — Glauconycteris floweri (de Winton). 
Remarks. — The extraordinarily roughened surface of the forearm, 
tail, and tibia, together with the peculiar form of the skull and of 
the upper toothrow, distinguish this genus very sharply from its ally, 
Eptesicus. 
