320 NATURAL HISTORY. 



Lucia, in the West Indies. Other and very venomous Serpents of the group live on the mainland, 

 and the principal are Jararaca* and Bothrops atrox. 



Halys is the only East Indian genus of Pit Vipers or Crotalidse with a vestige of the rattle, 

 and it is reduced to a simple horny spine at the end of the tail. Many of these Indian 

 Crotalidce, such as the Trimeresurids, are arboreal Snakes, and in colour resemble the foliage or 

 branches of the trees in which they live. These Trimeresuri are said to be naturally sluggish, 



COPPER-HEAD SNAKE (AncistrodoK contoririx). 



and are apt to lie quietly, hidden by the leaves or branches they resemble in colour, until disturbed ; 

 then they are sometimes fiei-ce and aggressive, bite savagely, and make a hissing sound as they 

 prepare to strike, which they do by first drawing back the head and anterior part of the body, and 

 then darting it forward with great rapidity. Their tail is prehensile. 



The venomous Snakes kill by inoculating their victim with a liquid poison, which escapes by a 

 groove in front of the fang, or by canal formed by the cohesion of the edges of the groove. After 

 depriving their prey of the power of escape and resistance, they proceed to swallow it. On the other 

 hand, the non-venomous Snakes stop, and wound, and often kill with their well-developed solid teeth, 



* Craspedocephalus (Bothrops) brasiliensis. 



