THE FAMILIES AND GENERA OF BATS. 
55 
Genus PTEROCYON Peters. 
1861. Pterocyon Peters, Monatsber. k. preuss. Akad. Wissensch., Berlin, I, 
p. 423 (paleaceus=stramineus ) . 
1878. Gynonycteris Dobson, Catal. Ckiropt. Brit. Mus., p. 70 (part). 
1881. Leiponyx Jentink, Notes from the Leyden Museum, III, p. 59. 
( Leiponyx biittikoferi . ) 
1899. Pterocyon Matschie, Flederm. des Berliner Mus. fur Naturk., p. 62. 
(Subgenus of Xantharpyia=Rousettus.) 
1899. Leiponyx Matschie, Flederm. des Berliner Mus. fiir Naturk., p. 85. 
(genus.) 
Type-species. — Pteropus stramineus Geoffroy. 
Geographic distribution. — Arabia; Africa south of the Sahara; 
Madagascar. 
Number of forms . — -Three species of Pterocyon are now known. 
Characters . — Dental formula 
2 3. 1. - 23456 
1 2 
.2-2 ,1-1 3-3 2 - 2 _ Q , 
1. - 2 3 4 5 6 7 ''2 -2*' 1 1‘ 3 3‘ 3-3 34 
Teeth as in Rousettus ex- 
cept that the crowns of 
the lower incisors are not 
grooved on the anterior 
face, and the cutting edges 
are uniformly rounded." 
The skull (fig. 7), while in 
general closely resembling 
that of Rousettus is distin- 
guished by the remarkable 
development of the audital 
bullse, the outer portion of 
which is distinctly differen- 
tiated from the inner as a 
prominent lip or short tube 
surrounding the meatus. 
(Fig. 7.) Nothin 0, COinpar- fig. 7— A, Rousettus amplexicaudatus. adult female. 
, , Caves near Maulmain, Burma. No. 37930. x2. B, 
able tO tills Structure occurs Pterycyon stramineus. Adult female. Robertsport, 
in the related genera or in Liberia, no. 102461. x2. 
any of the bats that I have examined. External chraacters as in 
Rousettus. 
a In the species of Rousettus now known the crown of the first lower molar 
is scarcely longer than that of the second, while in Pterocyon stramineus and 
P. dupreanus it is about as long as the second and third together. This char- 
acter has been made very prominent by Matschie, but I do not consider it of 
special taxonomic importance, however convenient it may be as a means of 
recognizing members of the two genera. 
