POISON OF SOME INDIAN VENOMOUS SNAKES. 10;'. 



As the poison-glands of the snake are modified parotid 

 glands, we should naturally expect the poison to be excreted 

 by the salivary glands ; and we think it possible that the 

 immunity which poisonous snakes enjoy from the effects of 

 their own poison or that of another species (an immunity 

 which is not shared by innocuous serpents, nor even by small 

 individuals of a venomous species poisoned by a large dose of 

 venom) may be due, at least in some measure, to their power 

 of excreting the inoculated venom thi-ough their own poison- 

 glands. We have, however, had no opportunities of trying 

 whether venomous serpents, after extirpation of their poison- 

 gland, succumb to the bite of others in the same way as 

 innocuous ones. 



On the Means of lyreventing Death from the Bites of Venomous 



Snakes. 



In the case of all poisons, snake-venom included, there is 

 a dose which is insufficient to kill ; and animals may recover 

 from it even after the characteristic symptoms of the poison 

 have been distinctly manifested. 



It has been clearly shown by Hermann that the real dose of 

 any poison, or, in other words, the quantity which is actually 

 circulating in the Huids and operating on the tissues of the 

 body, depends on two factors, viz., the rapidity with which it 

 is absorbed and the rapidity with which it is excreted. If 

 absorption goes on more rapidly than excretion, the poison 

 accumulates in the blood and exercises its lethal action ; while 

 the quantity in actual circulation may be reduced to an infinite- 

 simal amount and deprived of all power for evil, if the excretion 

 can keep pace with, or go on more rapidly than, the absorption. 

 Thus it is that curare kills an animal when introduced into 

 a wound; for the poison is absorbed from the wound more 

 rapidly than it can be excreted by the kidneys. If placed in 

 the stomach, curare has usually no apparent action whatever ; 

 for it is excreted in the urine as quickly as it is absorbed by 

 the gastric walls. But if absorption be quickened by increasing 

 the quantity administered and giving it on an empty stomach, 

 curare will have the same effect as when it is placed in a wound 



