ON THE COMMON INDIA N SNA KES . 527 



Dimensions. —Adults vary from about 18 inches to two feet in 

 length, but larger specimens are sometimes met with. Dr. Imlach* 

 speaking of Sind says the average length of the kuppur is 15 inches. 

 Elliott in Madras says he has not seen a specimen larger than 16 

 inches. I am certain 1 have seen them larger than this in Southern 

 India. Colonel R. Light has written to our Society of examples he 

 has seen in Bhuj (Cutch) which measured 26^, 27|, and 27| inches. 

 The late Mr. L. C. H. Youngt recorded a specimen in this Journal 

 from Andheri near Bombay 2 feet 6 inches long. These are the 

 largest measurements known to me. 



Bodily configuration, etc. — Its figure is typically viperine, that is 

 to say, the body compared with that of colubrine snakes is relatively 

 stout for its length, and reduces perceptibly anteriorly and posteri- 

 orly. The anterior attenuation makes the neck conspicuous behind 

 the broader head. Dorsally the whole body is rough from the keeled 

 condition of the scales, especially so laterally, where the keels are 

 serrated. The roughness and lustreless character of the scales on 

 the back and flanks are in marked contrast to the beautifully smooth 

 and polished surfaces of the ventral shields, and both doubtless 

 greatly assist colouration in rendering the creature inconspicuous 

 amid its desert environment. The head is subovate or roughly pear- 

 shaped seen from above, and the snout rounded. The muzzle is 

 rounded from side to side unlike many of the pit vipers in which a 

 more or less sharp ridge (canthus rostralis) separates the face from 

 the crown. The nostril is placed rather high, and between two 

 shields, and is notably small in comparison with Russell's viper. 

 The eye is large, the iris golden yellow, and the pupil vertical in 

 shape as in all other vipers. The commissure of the mouth is truly 

 viperine, the upper lip presenting a downward rounded prominence 

 situated below the anterior margin of the eye, and corresponding 

 with the position of the fang as placed when the mouth is shut. 

 Our plate shows this very well in figure G, which should be com- 

 pared with figure 2. The tail is very evident owing to the great 

 attenuation in calibre which occurs at the anal region, and it tapers 

 very rapidly as in other vipers. It is short, being about one-tenth to 



* Trans. Medl. and Phys. Soc. of Bombay, 1855 to 185(5, p. 80. 

 f Trans. S. Ind. Br. of Brit. Medl. Assoctn., 1895, p. 13. 

 % Vol. xvi. p. 504. 



