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CHAPTER VI. 



THE PHYSIOLOGICAL ACTION OF SNAKE-VENOMS. 



A. — Physiology op Poisoning in Man and in Animals Bitten 

 BY THE Different Species of Poisonous Snakes. 



(ColubridcB ; Viperida ; HijdrophiidcB.) 



The bites of poisonous snakes produce very different effects 

 according to the species of snake, the species to which the animal 

 bitten belongs, and according to the situation of the bite. It is 

 therefore necessary to take these various factors into account, in 

 describing the symptoms of poisoning in different animals. 



When the quantity of venom introduced into the tissues by 

 the bite of the reptile is sufficient to produce fatal results — which 

 is happily not always the case — the venom manifests its toxic action 

 in two series of phenomena : the first of these is local and affects 

 only the seat and surroundings of the bite ; the second, or general 

 series, is seen in the effects produced upon the circulation and 

 nervous system. 



It is remarkable to find how great is the importance of the local 

 disorders when the venomous reptile belongs to the Solenoglypha 

 group (Vipebid^), while it is almost nil in the case of the Protero- 

 glypha (Colubeid^ and Hydrophiid^). 



The effects of general intoxication, on the contrary, are much 

 more intense and more rapid with the venom of Proteroglypha, 

 than with that of Solenoglypha. 



In considering the usual phenomena of snake-poisoning in man , 

 we must therefore take this essential difference into account, and 



