66 VIPERAD^E. 



Although there is no reason to believe that the Viper 

 employs this powerful means of destruction for the purpose 

 of disabling its prey before it is finally seized ; but, on the 

 contrary, all the observations which have been made upon 

 its mode of feeding, tend to shew that, like the Snake, it 

 seizes its prey at once, and immediately begins to swallow 

 it ; yet it is not at all improbable, considering how instant- 

 aneously the poison begins to affect small animals, that 

 even in the act of seizing a mouse or bird, or any other 

 victim, it may instil a sufficient quantity of venom into 

 its system to paralyze and presently destroy it. Still the 

 action by which it takes its prey is very different from 

 that which it employs in its defensive attack, and resem- 

 bles that employed by the innocuous tribes. Its favourite 

 food consists of the smaller mammalia, field-mice, shrews, 

 and similar little animals, of frogs also, though less com- 

 monly, and occasionally of birds. It does not always con- 

 fine its voracity within the limits of its powers of deglu- 

 tition ; for I have in my possession a specimen of a small 

 Viper which was taken on Poole Heath in Dorsetshire, in 

 a dying state, in the act of attempting to swallow a mouse 

 which was too large for it, the skin of the neck being so 

 distended as to have burst in several places. 



The Viper, like many others of the poisonous groups of 

 Serpents, is ovo-viviparous. I have concluded, from the 

 examination of many specimens, both of this species and of 

 the Rattlesnake, that it is in the act of parturition that the 

 membrane of the egg is burst. I have examined several in 

 which the young have appeared ready to be excluded ; 

 but have always found the investing membrane entire ; 

 although so thin and soft as to be torn by the slightest 

 force. I give a figure of the young Viper in this state, 

 the membrane having been removed. It is coiled up so 



