ON THE COMMON INDJAN SNAKES. 531 



the most active, and aggressive poisonous snake I have seen." Again 

 he says (p. 137) : " I may remind the reader that the Echis carinata 

 is a very active and fierce little viper, very aggressive, minaceous 

 and irascible * * * in striking the head was always erect, and the 

 whole aspect and attitude was that of intense malice, and mischief." 



Habits. — The curious rubbing movement alluded to by Fayrer is 

 probably peculiar to the genera Echis, and Cerastes, at least one 

 may presume that Echis color at a and the two species of horned viper 

 of Africa behave similarly since they all have the same saw keels and 

 oblique costal scales. Echis carinata is the only one of the four 

 that occurs in India. 



Mr. Millard alludes to the peculiar movement adopted by this 

 viper in causing the friction of its scales, thus : " It has a curious 

 habit of revolving in almost the figure 8 with its head always in the 

 centre." Fayrer's* plate shows the attitude referred to by Mr. Millard 

 very well. 



The hissing noise, and its production are among the most interest- 

 in o- features connected with this snake. From four to seven of the 

 costal series above the penultimate row are peculiarly oblique as seen 

 in our plate. In these rows and these only the keels are serrated, 

 and when the sides of the body rub against one another, the teeth 

 on the opposing faces scrape together, producing a noise so like 

 hissino- that the onlooker ignorant of the method in which the 

 sound is really produced may well be deceived. The volume of 



sound is doubtless very greatly 

 yVtlW> / vyUv r i _ intensified by the habit this 



snake possesses, in common with 

 many others, of inflating itself 



_ . , . . , , . , . under excitement. The result 



Oide view of oblique costal 



*/ i is the production ot a column oi 



scale lo show serrated keel. • -> • -ii,' ,„u;^ ;,, 



imprisoned air witnm, wnicn in 



(After Boulenger.J this case acts as a resonant 



chamber. Fayrer remarks that 



he thinks this viper does not hiss. Whether it does so or not, 



no ordinary hissing except perhaps that of the Daboia would 



be likely to be audible during the production of this loud false 



hissing sound. In Delhi I frequently saw a heap of these 



* Loc. cit., pi. XIL 



