330 CLASS REPTILIA. 



usually inhabit aquatic situations, placing themselves in am- 

 buscade on the banks of rivers, where animals come to quench 

 their thirst. Rolled upon themselves in spires, they form a 

 disk of nearly seven feet in diameter, in the centre of which 

 the head is placed. They thus await their prey in a motion- 

 less position, only raising the head occasionally some feet 

 above this sort of spiral, to observe if any animal approaches. 

 As soon as they imagine it within their reach, they shoot 

 forth like a spring. They twist round its neck for the pur- 

 pose of strangling it. When the animal is strangled, they 

 break its bones, by squeezing it with the numerous folds 

 of their body. They then extend it on the earth, cover it 

 with their mucous saliva, and begin to swallow it, taking 

 the head first. In this sort of deglutition the two jaws 

 of the serpent dilate excessively, so that it seems to swallow 

 a body larger than itself. In the mean time, digestion begins 

 to take place in the oesophagus. Then the serpent becomes 

 lethargic, and is very easily killed, for he neither offers resist- 

 ance, nor attempts to fly. 



We have seen that, from the numerous and ill-digested 

 genus Coluber of Linnaeus, many separations have been 

 made, independently of that of those serpents which are not 

 venomous. We shall notice some of the more remarkable. 



The name Python was bestowed by Daudin on a genus 

 very much indeed approximating to Boa, and which our au- 

 thor conceives to contain all the pretended boas of the ancient 

 continent. Among the species of this genus, the one most 

 worthy of remark is the ular-sacra, Python amethystinus, 

 Daud ; Javan snake ; Col. Javanicus of Shaw. This ser- 

 pent, which is as large as any boa, coming to more than thirty 

 feet in length, inhabits the island of Java. The meaning of 

 its Javanese name is serpent of the rice-Jields, because it lives 

 in them habitually. Its bite is not venomous. It usually 

 lives on rats and birds, and sometimes on larger animals. 



