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Show 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 nearlysevered from the body. There is an azygos shield more in front than betweent he supranasals ; and the scales of the head are larger than in that species. The tail is certainly shorter than in T. monticola, 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. c. 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, Schneid.; 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 m e has the superciliary region scaly and 166 ventrals, while another, from Singhbhoom, has also a scaly superciliary but only 138 ventrals. This large number of ventral 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. W e discover that the first row of scales above the ventrals are perfectly 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 longitudinally. By this arrangement the serrated keels of the scales are made to pass over each other obliquely instead of in a straight line, |