The Rattlesnakes 



has departed, wlu'n it uncoils and begins an examination of the 

 prey. This is a careful and quite extraordinary performance. 

 Gliding about the rabbit it places its snout close to the animal's 

 body and probes with the tongue tips into the fur. The examina- 

 tion leads finally to the dead creature's head and here the snake 

 makes a more detailed investigation. The slightest move on the 

 part of the observer would probably conclude the whole affair, 

 the snake rattling sharply for a few seconds, then leaving the 

 prey, coils up again and refuses to eat. But in the event of not 

 being disturbed, touches the head lightly with the tongue tips, 

 a dozen times or more. At last opening its mouth, the snake 

 seizes its prey by the nose, when the engulfing process begins, 

 the long fang lending valuable assistance in hooking the animal 

 into the reptile's mouth and throat. 



The Diamond-back Rattlesnake gives bir^h to from seven to 

 twelve young. These feed readily upon mice at the start, and 

 grow rapidly, fully maturing within two years. Captive-bred 

 specimens are quiet, good-natured and feed voraciously. They 

 are hence more satisfactory than specimens captured wild. 



THE WESTERN DIAMOND RATTLESNAKE 

 Crotalus atrox, (B. & G.) 



Next to the diamond-back rattlesnake of the southeastern 

 United States, this is the largest species of the genus. It attains 

 a length of seven feet. 



Colouralion. — The pattern is very similar to that of the pre- 

 ceding and allied species, but the ground-colour is different as 

 is the fail, which is white, with jei-black rings. 



The ground-colour may be yellowish gray, pale, bluish gray 

 or pinkish, according to locality; the pale borders of the diamond 

 markings are dull white. Compared with the rich, olive and 

 yellow tints of the Eastern species, the present reptile evinces 

 a dull and faded pattern. 



The most showy individuals are from the desert regions of 

 Arizona. The ground-colour is distinctly pinkish, the borders 

 of the rhombs vividly outlined in white; the tail chalky white 

 with jet-black rings. 



On all specimens the head markings are similar to the allied 

 species, but the pale stripes on the side of the head are not so 

 vividly defined. 



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