242 W. L. Sclater — Knfes on the Snahes in the Indian Museum. [No. 3, 



loreal squarish ; one large preocular reaoliing the top of the head, but 

 not touching the vertical ; three postoculars ; temporals 1 + 2, the pos- 

 terior pair very much smaller than, the anterior and hardly larger than 

 the scales around ; upper labials 7 or 8, the third and fourth, or fourth 

 and fifth entering the eye ; five pairs of lower labials in contact with the 

 anterior chin shields which are much shorter than the posterior ones. 

 Scales in 19 rows strongly keeled including the outer row ; ventrals 162 ; 

 subcaudals 119 ; anal divided. 



Colour, above bluish olive with a longitudinal dorsal band from the 

 nape to the tail about two scales wide bordered on either side by a nar- 

 row black line, another indistinct white line laterally on either side, head 

 uniform, a black streak behind the eye ; below lighter than above, uni- 

 form ; chin, upper labials and snout yellowish without the bluish tinge. 



The only example of this new species is one from Camorta in the 

 Nicobars, procured there by Mr. de Roepstorff. 



I have referred this snake to Tropidonotus, but T am by no means 

 certain that it is properly there located ; the only example in the Museum 

 is a small and obviously young one, and I cannot make out that there is 

 very much difference in the size of the maxillary teeth, and the num- 

 ber of subcaudals is very high for this genus ; the only species which 

 it seems to resemble at all is Prymniodon chalceus, Cope (Giinther, Rep- 

 tiles Brit. Ind. p. 274) which is said to have come from Siam ; with the 

 description of this species in Giinther, it agrees admirably except in the 

 two important characters of the dentition and the anal shield. 



The maxillary teeth of Prymniodon are said to be very considerably 

 larger anteriorly than posteriorly, and the anal shield is entire ; in the 

 species before me the maxillary teeth appear to be of equal length 

 throughout, and the anal is divided ; it is therefore impossible to identi- 

 fy the Nicobar species with Prymniodon and I have thought it best, until 

 more specimens are forthcoming to leave it in the genus Tropidonotus. 



Tbopidonotus rhodomelas, Boie, Blanford, P. Z. S. 1881, p. 221. 



Tropidonofus mortoni, Theobald, (Cat. Rept. As. Soc. Mus. p. 57) is 

 referable to this species of which we have examples from Singapore and 

 Sinkip Island, Sumatra. 



Tropidonotds trianguligbrus, Schleg., Anderson, Journ. Lin. Soc. xxi, 



p. 345. 

 This snake was obtained by Dr. Anderson in Mergui and the Mu- 

 seum also contains examples from North Tenasserim, the Malay Penin- 

 sula and from Sinldp Island, Sumatra ; it is not mentioned by Boulen- 

 ger, and must be added to the Indian Fauna. 



