The Rattlesnakes 



9 



THE DIAMOND-BACK RATTLESNAKE 

 Crotalus adamanteus, (Beauvois) 



Largest of the rattlesnakes. Fully adult specimens are 

 from six to eight feet long. The body is stout and heavy, the 

 head very broad, flat and distinct from the neck. 



Colouration. Olive or grayish green, with a chain of large, 

 diamond markings of a darker hue, these with bright yellow bor- 

 ders about the width of a single scale. The rhombs usually en- 

 close a patch of the ground-colour; toward the tail they become 

 obscure and finally fuse into cross-bands; the tail above is olive, 

 ringed with black. The abdomen is dull yellow. 



On the top, the head is brown or olive, with numerous dark 

 spots. Beneath the eye is a dark band, bordered on each side 

 with a narrow band of bright yellow. 



With the exception of a more vivid pattern, young specimens 

 are like the parent. 



Dimensions. The largest specimen measured by the 

 writer was eight feet, three inches in length. Its diameter was 

 four and a half inches, and the head three and a quarter inches 

 wide. Specimens of such dimensions are rare. This large spec- 

 imen was captured in the central portion of the Florida peninsula. 

 The measurements quoted are of a specimen taken in the vicinity 

 of the Indian River, Florida: 



Total Length 6 feet, 3 inches. 



Length of Tail, exclusive of rattle 6 



Length of Rattle, 9 segments 2 



Greatest Diameter of Body 4 



Width of Head 2 



Length of Head 3 



The fangs of this specimen were seven-eighths of an inch in 

 length. 



Compared with the most deadly known species of poisonous 

 snakes of the world, the Diamond-back Rattlesnake ranks second 

 to none. Its huge fangs, and enormous poison glands, represent 

 the maximum degree of deadliness attained by the viperine 

 serpents. The well-known and terrible bushmaster, (Lachesis 

 mutus) of tropical South America attains a larger size than this 

 rattlesnake and consequently has larger fangs, but a careful 

 examination of the fangs of the two species will show that the 

 opening at the tip of the tooth for the ejection of venom is 



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