The Rattlesnakes 



weeks later when the snake a black Timber Rattlesnake was 

 so disturbed that it became greatly enraged and rattled steadily 

 for about an hour. The writer was once asked to examine what 

 was considered a unique possession in one of our large scientific 

 institutions. This was a rattle consisting of twenty-four rings. 

 Close inspection showed the wonderful organ to be composed of 

 the rattles of three snakes of similar size, snapped into one another. 

 This is easily done. On many occasions in the reptile house of 

 the New York Zoological Park it has been found appropriate 

 to adorn fine rattlers that have lost their chief ornament in the 

 excitement of capture, with a rattle from the souvenir box of such 

 curiosities. (A figure shows the internal composition of the rattle). 



The Rattlesnakes are divided into two genera Sistrurus, 

 the Pigmy Rattlesnakes, and Crotalus containing the majority 

 of the species. The species of Sistrurus are small, rarely attaining 

 a thickness of a man's forefinger and a length of a yard. Crotalus 

 contains species both large and small. A small Rattlesnake is 

 one that attains a length of not more than three feet. The large 

 species reach a length of six to eight feet. 



A definition is presented of the two genera of Rattlesnakes : 



Top of head with large, symmetrical shields. Size small. 

 Two species and two varieties in the United States. 



Genus Sistrurus. 



Top of head with granular scales with some species a 

 few small shields on snout, in front of eyes. Eleven species 

 and two varieties in the United States. Genus Crotalus. 



The Pigmy Rattlesnakes, Sistrurus: For the snakes of 

 this genus, the popular title of "Ground Rattlesnakes" has 

 become almost proverbial. The writer has decided to drop this 

 name, as one altogether inappropriate. It is really difficult to 

 imagine how such a name could originate. The title is rpislead- 

 ing for it tends to signify that these Rattlesnakes live on the 

 ground, and might thus bring the beginner to imagine that the 

 members of the larger genus Crotalus live in the trees. All 

 of the Rattlesnakes are ground reptiles, as none of them exhibits 

 a liking for climbing or swimming. Hence it is altogether wrong 

 to select a small genus of this important group and term the mem- 

 bers the ground Rattlesnakes. As the species of Sistrurus are of 

 very small size as compared to the average Rattlesnake, the 



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