The Rattlesnakes 



Variations. The ground-colour varies considerably. Some 

 specimens are almost black. A specimen examined, from the 

 Beaver Mountains, in Utah, is pale green, with sooty black 

 saddles on the back and none upon the sides. The blotches 

 contained none of the ground-colour as is usually the case. 



Dimensions. An adult specimen, from Beaver County, 

 Utah, and having a rattle consisting of five uniform segments, 

 showed the following measurements: 



Total Length 34 inches. 



Tail, exclusive of rattle 2| 



Greatest Diameter i 



Width of Head i " 



Length of Head if 



Distribution. The Pacific region, from southern British 

 Columbia to southern California. Also occurs in Idaho, Nevada 

 and Utah. It inhabits mountainous regions to an altitude of 

 1 1,000 feet. 



Habits. Similar to the prairie rattlesnake. It is hardy 

 in captivity. 



THE TIGER RATTLESNAKE 

 Crotalus tigris, (Kennicott) 



The Tiger Rattlesnake attains a moderate length seldom 

 more than three and a half feet. Its conformation does not 

 materially differ from that of the prairie and Pacific rattles- 

 snakes. 



Colouration. Yellowish gray, with a series of small and 

 not very distinct blotches on the back and on each side, for the 

 forward third of the body; on the latter two-thirds, these blotches 

 fuse into regular cross-bands, producing a strongly barred effect. 

 There is usually a dark bar from the eye to the angle of the mouth. 



Several specimens from the mountains of southwestern 

 Arizona looked quite black upon a gross examination. Ex- 

 amined closely, the pale ground-colour appeared only as dull gray 

 bars on the sides of the latter portion of the body. 



Dimensions. The largest specimen examined was forty 

 inches long. Its proportions were rather more slender than the 

 Pacific rattlesnake. 



Distribution. Desert mountains of Arizona, Nevada and 

 southern California. 



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