108 INDIAN SNAKE POISONS, 



that paralysis of accommodation occurs. In regard to 

 the relative power of the cohra and the Australian colu- 

 brine snakes, five cases of cobra-bite in dogs, taken 

 indiscriminately, gave an average time before death of 

 34'4 minutes ; whereas the Australian Hoplocephalus 

 curtus took, in five cases selected on account of their 

 rapidity, an average time of 84 minutes, or about two 

 and a half times as long, and the average time required 

 to destroy human life seems about eighteen hours by 

 the Hoplocephalus. Chronic constitutional poisoning 

 does not seem to occur with this snake, as in no case 

 did death in the human subject occur after forty-eight 

 hours ; in one case, in a dog that was hypodermically 

 injected, death took place in sixty-six hours, and this 

 seems the extreme limit, forty-nine hours being the 

 longest period of all the cases of cobra-bite given in 

 Sir Joseph Fayrer's " Thanatophidia." 



The literature of American snake-poisoning is also 

 somewhat meagre, but the most valuable information 

 on the subject is undoubtedly contained in Dr. Weir 

 Mitchell's " Eesearches upon the Venom of the Rattle- 

 snake." 



The Crotalus, or American rattle-snake,'of which there 

 are many species, is, of course, a viper distinguished 

 both by the peculiarity of its tail, constituting the so- 

 called rattle, and by a depression on the lateral aspect 

 of the head, from which it has sometimes been tfi-med 

 & " pit-viper." 



