316 AMERICAN SNAKES. 



prejudice against the serpent tribe, the number of 

 human beings actually injured by them is very small. 

 The rattlesnake, like most venomous reptiles, seldom 

 makes an unprovoked attack upon man. 



The structure of the rattle found on this class of 

 reptiles is very curious. It has been supposed to 

 consist of a number of bones loosely contained in a 

 horny case, the agitation of which produces the noise. 

 This is not the fact ; it is made up of a number of 

 rings received upon each other, and movable ; only the 

 first being firmly attached to the last vertebra of the tail. 



The number of these rings depends upon the age of the 

 snake, one being added to the rattle every time the 

 reptile changes its skin. Twelve is considered a good 

 number, though there are stories going the round of 

 camp fires, of immense snakes that have been killed 

 with as many as thirty rattles. The noise is produced 

 by the snake shaking its tail, the motion knocking the 

 rings against each other; and the noise is greater or 

 less, according to the quickness with which the tail is 

 moved. If the animal is very angry, it shakes the 

 rattle so violently that it can hardly be seen, and the 

 noise is excessively loud, resembling that which would 

 be produced if a quantity of loose substances were 

 placed in a tube, closed at each end with parchment, 

 and shaken. It is said to be perfectly audible at the 

 distance of a hundred feet ; while at other times, when 

 nothing has occurred to excite the snake's anger, it can 



