3^ 



THE SNAKES OF SOUTH AFRICA. 



victim's body as far down as possible. Tlien there is a short 

 rest, followed by another expansion of the jaws and the same 

 contraction of the muscles of the head. Slowly, but surely, the 

 prey is seen to vanish from sight. When the hindquarters have 

 disappeared into the throat of the snake, the task is easy. The 

 muscles of the body set up a series of contractions which force 

 the creature down the gullet into the stomach tube. When it 

 gets to the middle part of the snake where the real stomach is 

 situated, the victim's body goes no further, until digested or 

 disgorged. Sometimes a snake will seize a large rat, toad, or 

 frog and begin by swallowing one of the hind legs. Finding that 



Fig. i8. — A Puff Adder swallowing a large Barn Rat. Nute huw tlu' Miakc makes use of 

 his fangs to help to get the body of his victim into his mouth. 



eventually he cannot make much progress, he rejects the swallowed 

 leg and moves round to the head and begins again. 



I have seen a Puff Adder in captivity swallow three rats in 

 succession. So powerful were its digestive juices that it com- 

 pletely digested them all. Boomslangs will, at times, swallow 

 seven to a dozen frogs in rapid succession. When the prey 

 is of small bulk, it is quickly swallowed. A Puff Adder takes 

 from half an hour to a full hour, and sometimes longer, to swallow 

 a large rat. 



Power of Disgorging Prey. 



It is popularly supposed that snakes cannot release their 

 prey once it is well within their jaws, owing to the nature of their 

 teeth, which are curved backwards. On the contrary, when 



