The Start ii 



have small teeth which cannot penetrate even ordinary 

 clothing. They are only dangerous if actually trodden 

 on by some one with bare feet or if seized in the hand. 

 There are harmless snakes very like them in color which 

 are sometimes kept as pets; but it behooves every man 

 who keeps such a pet or who handles such a snake to be 

 very sure as to the genus to which it belongs. 



The great bulk of the poisonous snakes of America, 

 including all the really dangerous ones, belong to a divi- 

 sion of the widely spread family of vipers which is 

 known as the pit-vipers. In South America these in- 

 clude two distinct subfamilies or genera — ^whether they 

 are called families, subfamilies, or genera would depend, 

 I suppose, largely upon the varying personal views of 

 the individual describer on the subject of herpetological 

 nomenclature. One genus includes the rattlesnakes, of 

 which the big Brazilian species is as dangerous as those 

 of the southern United States. But the large majority 

 of the species and individuals of dangerous snakes in 

 tropical America are included in the genus lachecis. 

 These are active, vicious, aggressive snakes without rat- 

 tles. They are exceedingly poisonous. Some of them 

 grow to a very large size, being indeed among the largest 

 poisonous snakes in the world — ^their only rivals in this 

 respect being the diamond rattlesnake of Florida, one 

 of the African mambas, and the Indian hamadryad, or 

 snake-eating cobra. The fer-de-lance, so dreaded in 

 Martinique, and the equally dangerous bushmaster of 

 Guiana are included in this genus. A dozen species are 

 known in Brazil, the biggest one being identical with 

 the Guiana bushmaster, and the most common one, the 



