276 Proceedings of the Asiatic Society. [No. 3. 



Sc. atrodorsalis, Gray. A iiae and instructive series of this variable 

 species, wherein the hue of the under-parts varies from pale buff to dark 

 maronne, and the black patch on the back — greatly developed in some, is 

 entirely wanting in others. The face appears always to be reddish, the 

 ears deep rufous, and the whiskers are conspicuously white, whereas iu 

 the last two species they are black. Tail more or less bushy, its long 

 hair tipped either with rufous or whitish, and sometimes a distinct white 

 tip. It would seem that the young are pale rufous-buff underneath, with 

 no black patch on the back ; and one without black upon the back has 

 the breast pale and the sides and belly maronne, whereas another has 

 pale under-parts throughout and a large black dorsal patch. A common 

 species at Moulmein. 



Sc. Barbei, nobis, /. A. S. XVI, 875. 



Pteromys cineraceus, nobis : sent also by Colonel Phayre from Pegu, 

 as formerly from Arakan ; together with a Sciukoptera from Pegu, 

 received formerly from Mergui, and which I considered to be Sc. sagitta, 

 but shall now designate Sc. Phayrei.* 



* The f Flying Squirrels' are among the most difficult of groups in which to 

 define the species or perhaps local races. Eighteen specimens of Pteromys were 

 e xhibited at the Meeting, which are referable to six distinguishable races ; and sixteen 

 specimens of Scidroptera, which are referable to seven species or distinguishable 

 races, that are better characterized than those of Pteromys. The whole are con- 

 tinental, and there are also various races in the archipelago ; besides which, we have 

 not yet examples of all of the continental races which have been described, nor of 

 Sc. Layardi from Ceylon. I will endeavour to elucidate the grand series, distin- 

 guishing those of which we possess specimens by prefixing an asterisk. 



*1. Pteromys petaurista ; Sciurus petaurista (mas), Pallas: Ft. philip- 

 pensiSy Gray, apud Elliot ; Pt, oral, Tickell. Found without variation over the 

 forests of the whole Indian peninsula and also Ceylon. Of a dark maronne ; having 

 the fur tipped with white on the head and back : feet, and greater portion of the 

 tail, black, the latter with occasionally a white extreme tip : lower-parts white more 

 or less pure. 



*2. Pt. cineraceus, nobis; Ft. petaurista, var. cineraceus, nobis, J. A. S. 

 XVI, 865. From the Burmese countries — Arakan, Pegu, Tenasserim. Very like 

 the last, but the fur more uniformly white-tipped, even on the parachute-mem- 

 brane ; paws black ; and tail generally white almost to the end, but mostly black at 

 the extreme tip : lower-parts white, more or less pure. 



3. Pt. philippensis (verus), Gray. Founded (it may be presumed) upon 

 Buffon's description of the Tayuan from the Philippines, in Hist. Nat., Supp. 

 Ill, 150. 



