The Rattlesnakes 



Distribution. Desert areas of Arizona, southern Nevada, 

 southwestern Utah and eastern California. 



Habits. In its methods of progression this very interesting 

 snake differs from every other North American serpent. The 

 remarkable fashion in which it loops its way over the desert 

 sands is an exact reproduction of the motions displayed by the 

 several species of vipers that inhabit the borders of the African 

 and Arabian deserts. 



When progressing in a very leisurely manner the Horned 

 Rattlesnake glides almost in a straight line, as do all Rattle- 

 snakes very slowly, with head slightly raised and horizontal. 

 It is when the creature quickens its gait that the movements 

 become complicated and altogether unlike those of a serpent. 

 The progression is by a series of large loops of the body thrown 

 forward; one loop follows another with perfect symmetry of 

 alternation, while the snake moves off at a sharply oblique angle 

 to the direction in which the head is pointing and with such a 

 degree of agility that the spectacle is not only grotesque, but 

 bewildering. It in no way resembles a crawl; it is a walking 

 movement. 



Here we see Nature's admirable provision to enable a heavy- 

 bodied snake to progress at some speed over desert sands. That 

 this is the only fashion in which a thick-bodied snake could 

 display agility on soft soil is well illustrated by the fact that these 

 singular movements have been adopted by the vipers of the Afri- 

 can deserts and again, far removed from them, by our one species 

 of rattlesnake that inhabits the desert proper. 



THE GREEN RATTLESNAKE 



Crotalus Upidus, (Kennicott) 



The smallest species of the genus. Its conformation differs 

 from the other rattlesnakes as the body is quite slender, though 

 the head is broad, flat and distinct from the neck. This species 

 has twenty-three rows of scales. 



Colouration. Greenish-gray, or rich, dark green above, 

 crossed at wide intervals by narrow, jet-black bands. The bands 

 are usually bordered with pale, greenish-yellow. The abdomen 

 is pinkish, or yellowish-white. 



Immediately behind the head is a black blotch that is bluntly 

 forked in front. Between the black bands on the body are 



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