THE FAMILIES AND GENERA OP BATS. 

 Genus PTEROCYON Peters. 



55 



1861. Pterocyon Peters, Monatsber. k. preuss. Akad. Wissensch., Berlin, I, 



p. 423 (paleaceus=stramineus) . 

 1878. Cynonycteris Dobson, Catal. Chiropt. Brit. Mus., p. 70 (part). 

 1881. Leiponyx Jentink, Notes from the Leydeu Museum, III, p. 59. 



(Leiponyx buttikoferi.) 

 1899. Pterocyon Matschie, Flederm. des Berliner Mus. fur Naturk., p. 62. 



(Subgenus of Xantharpyia=Rousettus.) 

 1899. Leiponyx Matschie, Flederm. des Berliner Mus. ftir 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. 



2345 6- .2 



2 1 

 c 



1. -234567 2-2' 1-1 



pin 



3-3 2-2 

 '"3^3' m 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 

 bullae, the outer portion of 

 which is distinctly differen- 

 tiated from the inner as a 

 prominent lip or short tube 

 surrounding the meatus. 

 ( Fig. 7. ) Nothing compar- 

 able to this structure occurs 

 in the related genera or in 

 any of the bats that I have examined 

 Rousettus. 



Fig. "I— A, Rousettus amplexicaudatus. adult female. 

 Caves near Maulmain, Burma. No. 37930. x2. B, 

 Pterycyonstramineus. Adult female. Robertsport, 

 Liberia. No. 102461. x2. 



External chraacters as in 



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. 



