OF THE GLANDS. 49 



more speedily <according as the quantity of the poison has 

 been considerable, and has been introduced into a part of 

 the body abounding in sanguiferous vessels. Hence the 

 reason Avhy the bite of a large species is more dangerous 

 than that of the small, and why a deep puncture, or one 

 in a vein, is almost always mortal, whilst it is often not 

 followed by any bad consequence, where it only reaches 

 hard and callous parts of the body.* We must, however, 

 attribute the greater or less activity of the poison to seve- 

 ral other causes than those already cited. Sometimes it 

 is but a single tooth which enters the flesh, at other times 

 both instil their venom ; the fangs penetrate with more 

 facility in a slender part of the body, as a finger, than in 

 the thigh or the trunk. Serpents, also, in biting several 

 times, expend their venom, so that the last wounds are 

 less dangerous than the first. We must also take into 

 account the size of the animal bitten, as compared to that 

 of the serpent ; in Europe, man rarely perishes from the 

 bite of our viper ; it requires from three to four vipers to 

 kill a horse or an ox, whilst a single bite is sufficient to 

 kill in a short time one of the small mammifera. It is not 

 so in tropical countries, where a bite from a large venom- 

 ous snake has generally fatal effects in man and in other 

 animals. Thus, it may be considered as a law, that the 

 activity of the poison augments with the warmth of the 

 climate ; that the bite is more dangerous according to the 

 quantity of the poison instilled into the wound, and ac- 

 cording as the animal that inflicted the wound, and its 

 victim, were agitated by violent emotions. Innumerable 

 experiments have been instituted to determine the degree 

 of activity of the poison in different species of serpents, and 



* The poison has much less effect on cold blooded animals than on 

 mammals or on birds ; on most of the invertebrata it produces no effect 

 whatever. These facts shew that the term poison is not always used in 

 its primitive sense, but rather in a relative sense, and more particularly 

 with relation to the effects which this fluid produces on man or on animals 

 with red blood. This circumstance appears to have given rise to the 

 opinion advanced by some naturalists, that the viper itself, and other 

 animals, as the Anguis fragilis or slow-worm, the buzzard, were proof 

 against the bites of venomous snakes : the alleged facts have never been 

 proved by any positive experiments. 



