PTEROMYS GENIBARBIS. 



parts of the membrane are sooty-brown, diversified with grayish hairs, scattered 

 singly, or in tufts ; on the thick lanuginous covering of the posterior extremities, 

 the colour is hghter; on the extreme border it is gray. The hairs are whitish, closely 

 arranged, and delicate along the cartilage by which the membrane is expanded ; at 

 the extremity they form a close fringe, which is continued along the entire lateral 

 border of the membrane. On the feet and toes, short, delicate, grayish hairs are 

 scattered, not very closely. A greatly enlarged scrotum is a common character of 

 the different species of Pteromys ; in our animal, this part is covered with a soft, 

 white down. On the lateral parts of the head, between the ears and the termination 

 of the neck, the hairs are dispersed in small tufts, alternately of darker and lighter 

 shades ; and the separation between the upper and the lower parts is strongly marked 

 along the neck and shoulder. 



DIMENSIONS. 



• Inches Lines 



Length of the body and head, from the extremity of the nose 



to the root of the tail 8 9 



the tail 5 



head and neck 3 



anterior extremities, from the shoulder to the extremity 



of the claws 3 



cartilage supporting the flying-membrane 1 4 



posterior extremities 3 9 



The Pteromys genibarbis presents nothing peculiar in a generic point of view. 

 The Javanese species, generally, are distinguished by the length of the cartilage which 

 supports the flying-membrane : in two of our species, the tail is compressed, as in 

 the Pteromys hudsonius ; in the Pt. Petaurista, though it is greatly elongated, this 

 organ is cylindrical, as in the common European Flying Squirrels. 



The Pteromys genibarbis is very rarely met with in Java : I obtained a single 

 individual only, near the Eastern extremity of the Island, in the same districts 

 which also furnished the Delundung and the Tupaia to my collection. The most 

 assiduous research in the central districts did not procure me another individual. I 

 have reason to believe that the Sciurus Sagitta of Linn^us, which was probably 

 obtained near the Western extremity of Java, is equally rare. The description of 

 the latter, contained in the 12th Edition of the Systema Naturas of Linnseus, on the 

 authority of Nordgren, has the character of being carefully made on the spot ; the 

 size, the colour, and particularly the continuation of the membrane from the sides 

 of the head to the anterior extremities, shew it to be an animal clearly distinct from 



