810 EEPTILIA. 



end is marked by a distinct notcli. In the Muangla specimen, the two-fold 

 character of the nasals is also indicated by the epidermis peeling off along a similar 

 groove. I am therefore inclined to regard the normal condition of the nostril to be 

 that described by Giinther, although in the Yunnan snake the nasals are united 

 into a large shield. 



In the type of A. bicolor there is only one preocular, but in a specimen from the 

 Khasia HiUs in the British Museum, and in this snake from Yunnan, there are two 

 pre-oculars ; but it appears that the lowermost of these plates in these two specimens 

 must be regarded either as a separated portion of the third labial or of the 

 uppermost preocular, and that the number of the preoculars is thus a variable 

 character, because the type of C. bicolor, Blyth, and the British Museum specimen 

 referred to, agree in other respects. The Muangla specimen further indicates that 

 the number of postoculars is also a variable character, for the number of these 

 plates, unlike the former examples, is three, the most inferior resting on the 

 third and fourth labials over theu' suture, and thus excluding all the upper labials 

 from entering the orbit, this supplementary shield being apparently a separated 

 portion of the fourth upper labial. 



This Yimnan snake is one foot ten inches in length, but a smaU portion of the 

 tail is absent. The ventrals are 195, and the existing sub-caudals number 57. The 

 anal is bifid, and there are 17 rows of scales on the body. 



The colour is uniform dark olive-brown above, and orange-buff below. Each 

 scale has a dark-brown lateral margin and an obscure faint yellow tip, and all are 

 finely speckled with brown. The confluence, or continuity of the dark lateral margins 

 of the scales gives rise to an obscure, but finely longitudinally banded appearance. 



This species has hitherto been found only ia Assam and the Khasia Hills, but 

 its occurrence in Western Yunnan is in no way remarkable, because there is a 

 similarity between the fauna of the Khasia Hills and that of Yunnan. 



Ablabes collaris. Gray. 



Psammophis collaris, Gray, Ann. Mag. Nat. Hist., 1853, vol. xii, p. 390. 



Ablabes collaris, Giinth., Cat. Col. Snakes, 1858, p. 28; Rept. B. Ind., 1864, p. 228; Stol. Journ. 

 As. Soc, Bengal, 1870, pp. 140 and 184; id., op. cit., 1871, p. 430; Anders., Proc. Zool. Soc, 

 1871, p. .171; id., Journ. As. Soc, Bengal, 1871, p. 33; Strauch. Mem. Petersb., vol xxi, 

 1873-74, p. 41, pi. i, fig. 2; Theobald, Descr. Cat. Rept. Brit. Ind., 1876, p. 156. 



Only one specimen of this species was obtained by me in Yunnan, in the 

 Hotha vaUey. I have compared it with the type in the British Museum, with which 

 it agrees in all its essential characters. Ventrals 173. Tail imperfect. Head 0"-50 ; 

 gape 0"-38. Scales, 17 series. The teeth are of equal size, small, numerous and 

 crowded, 36 in each upper maxillary and 86 in the lower jaw, with 40 palatine teeth 

 on each side. 



Loreal square, or slightly elongated vertically. The lower angle of the 

 anterior nasal shield is on a level with the margin of the upper lip, and it excludes 



