576 SNAKES. 



might be feeble. In September of that year a Puff adder (I 

 think the same as the last named) bit a rat, which at first ran 

 about trying to escape, going close to the viper, as if uncon- 

 scious of an enemy, and apparently unharmed during the first 

 minute. Then it became aware of pain, and began to lash 

 its tail, whisking it round and round in a frantic manner. 

 Then one of its hind legs kicked out, probably the bitten 

 limb, jerking violently for a time, and the rat lay helpless 

 thus for about two minutes. In four minutes from the bite 

 it gasped, and continued to gasp harder and harder for nearly 

 three minutes more. It then bled at the mouth. The Puff 

 adder then bit it again, when, after two or three more minutes, 

 it leaped violently in convulsions from the effect of the 

 second bite. The convulsions became gradually less ; but 

 fully twenty minutes elapsed, in spite of a double charge of 

 venom, before the rat was dead. In all similar cases I 

 noticed that rats were very tenacious of life. A guinea-pig 

 has been killed in five seconds from the bite of a Puff 

 adder. 



On the same day, a 'nose-horned viper' {Viper a nasi- 

 cornis) struck a rabbit, which immediately ran and started 

 spasmodically, panting as if astonished and wondering what 

 had hurt him. Then he leaped into the well at the back 

 of the cage, but in that short moment was too feeble to crawl 

 back again. He attempted to run, but sank quickly. Being 

 out of sight, it was impossible to state the exact moment in 

 which it died, but the whole was in less than two minutes. 

 These vipers are no doubt intensely virulent. Another day 

 one of them with a bad swelled face from abscess bit a 

 guinea-pig, which in thirty seconds fell over on its side. It 



