196 DR. J. ANDERSON ON INDIAN REPTILES. [Feb. 21' 



Trimeresurus convictus, Stol. Journ. As. Soc. Bengal, xxxix. 

 p. 224. 



This species is very closely allied to T. monticola ; but, as Dr. 

 Stoliczka observes, the scales are slightly broader and more rhombic. 

 I presume he refers to the adults of that species ; but the specimen to 

 which the name T. convictus has been given is evidently not a full- 

 grown individual; for it only measures 11" 3'" (the body), and 

 1" 8'" (the tail). Now in the young of T. monticola I observe 

 that the scales are generally broader than in the adults, and the 

 keeling is very indistinct. "Moreover the head does not appear to 

 me to be higher than in T. monticola ; but, as Dr. Stoliczka remarks, 

 it is slightly more elliptical than in T. monticola : perhaps, however, 

 this appearance may be heightened from the circumstance that it is 

 nearly severed from the body. There is au azygos shield more in front 

 than betweent he supranas'als ; and the scales of the head are larger 

 than in that species. The tail is certainly shorter than in T. mon- 

 ticola, and the number of scales fewer. 



The single specimen of this species was obtained at an elevation 

 of 2400 feet, on the Western Hill, Penang. 



Halys himalayanus, Gthr. I.e. p. 393. 



One specimen before me has only twenty-one rows of strongly 

 keeled scales round the middle, only 154 ventrals, and 45 caudals. 



Dr. Stoliczka informs me that this species is far from uncommon 

 to the north-east of Simla. 



Echis carinata, Sclineid. ; Gthr. I.e. p. 397. 



This Viper is common in the country about Agra and Delhi, and 

 extends as far east as Singhbhoom, in Bengal, and to the south as 

 far as Madras. One specimen before me has the superciliary region 

 scaly and 1G6 ventrals, while another, from Singhbhoom, has also a 

 scaly superciliary but only 138 ventrals. This large number of ven- 

 tral shields induces me to regard the African and Asiatic snakes 

 as one. 



This Viper makes a curious, prolonged, almost hissing sound by 

 rubbing the sides of the folds of its body against each other. The 

 head remains almost fixed in one position, and the body is made to 

 move in folds in such a way that the sides are rubbed against each 

 other in the direction of the scales. When we come to examine the 

 latter structures it is at once apparent how the sound is produced. 

 We discover that the first row of scales above the ventrals are per- 

 fectly smooth, that the next one or two rows above these are strongly 

 keeled, and that in the three or five following rows the keel is very 

 strongly developed and toothed like a saw. These eight lateral rows 

 of scales are placed obliquely on the body, with their tips directed 

 downwards and backwards, while the other scales are placed longi- 

 tudinally. By this arrangement the serrated keels of the scales are 

 made to pass over each other obliquely instead of in a straight line, 



