126 THE STORY OF REPTILE LIFE. 



in favour of the view of the independent origin 

 of the poisonous snakes. 



The snakes of the genus Doliophis, allies of the 

 Cobras, are remarkable for the enormous size of 

 the poison bags, which extend far beyond the 

 head, along each side of the body, terminating 

 in club-shaped thickenings. Owing to their great 

 size the heart has been shifted further backwards 

 than in any other snake. 



The virulence of snake-poisons, and the 

 symptoms which follow its injection, differ con- 

 siderably. 



Of the first named is the much dreaded " Krait" 

 (Bungarus corulens), which is said to cause more 

 deaths in India than any other snake. It lives 

 chiefly on rats, lizards, and other snakes. Scarcely 

 less formidable is the "Hamadryad" or King- 

 Cobra, which attains a length of twelve feet, enor- 

 mous for a poisonous snake. Ranging from India 

 to South China and the Philippines, it is held in 

 detestation everywhere on account of its size and 

 poisonous properties. 



The African cobras have a remarkable habit 

 of squirting the poison from the mouth when 

 threatened, and are said to be able to throw 

 several feet. The object of such waste is not 

 easy to understand, since unless the venom 

 reaches a raw surface, or is injected into the flesh 

 by the teeth, it is powerless. 



Foremost among venomous snakes stand the 

 Vipers and Pit-vipers, inasmuch as it is among 

 these forms that the poison apparatus has reached 

 its highest perfection. To attain this, certain of 

 the jaw-bones have undergone considerable modi- 



