20 THROUGH THE BRAZILIAN WILDERNESS 



curious in itself, but it would also go far to explain the 

 failure of the mussurama to become plentiful. 



For the benefit of those who are not acquainted with 

 the subject, I may mention that the poison of a poisonous 

 snake is not dangerous to its own species unless injected 

 in very large doses, about ten times what would normally 

 be injected by a bite; but that it is deadly to all other 

 snakes, poisonous or non-poisonous, save as regards the 

 very few species which themselves eat poisonous snakes. 

 The Indian hamadryad, or giant cobra, is exclusively a 

 snake-eater. It evidently draws a sharp distinction between 

 poisonous and non-poisonous snakes, for Mr. Ditmars has 

 recorded that two individuals in the Bronx Zoo which are 

 habitually fed on harmless snakes, and attack them eagerly, 

 refused to attack a copperhead which was thrown into 

 their cage, being evidently afraid of this pit-viper. It 

 would be interesting to find out if the hamadryad is afraid 

 to prey on all pit-vipers, and also whether, it will prey on 

 its small relative, the true cobra — for it may well be that, 

 even if not immune to the viper poison, it is immune to 

 the poison of its close ally, the smaller cobra. 



All these and many other questions would be speedily 

 settled by Doctor Brazil if he were given the opportunity 

 to test them. It must be remembered, moreover, that not 

 only have his researches been of absorbing value from the 

 standpoint of pure science but that they also have a real 

 utilitarian worth. He is now collecting and breeding the 

 mussurama. The favorite prey of the mussurama is the 

 most common and therefore the most dangerous poison- 

 ous snake of Brazil, the jararaca, which is known in Mar- 

 tinique as the fer-de-lance. In Martinique and elsewhere 



