The Rattlesnakes 



While the Tiger Rattlesnake has for some time been con- 

 sidered a very rare species, numerous records show it to be 

 fairly common in the barren mountain ranges of the extreme 

 Southwest. A collector in southern California says that these 

 snakes live at a considerable elevation, but were not rare. To 

 back up his claim, he sent five specimens East. Mr. Herbert 

 Brown, of Yuma, Arizona, in a letter to the writer, says: "Dur- 

 ing the late overflows (1905) of the Colorado and Gila Rivers, 

 the snakes were driven from the valley lands and could be had 

 in any number on the higher benches. Black and yellow rattlers 

 (C. tigris) were very abundant. They are scarcer now." 



Habits. The Tiger Rattlesnake is not a very vicious species 

 if its habits may be judged by eight or ten captive specimens. 

 After a fe\v weeks in captivity it becomes lazy and good-natured. 

 Three specimens lived for about two years. They fed upon 

 mice, young rats and birds. 



THE HORNED RATTLESNAKE; "SIDE-WINDER" 

 Crotalus cerastes, (Hallowell) 



While this is one of the smallest species of Crotalus, it is the 

 most distinct, owing to the horn-like process over each eye, 

 which is really an elongation of the upper eye-shield (supraocular) . 

 The body is stout, with strongly keeled scales the three central 

 rows of scales having highly-raised keels, of tubercular formation. 



Colouration. Pale brown, yellow, or pinkish, with a series 

 of dull blotches, generally separated by white interspaces. On 

 the sides are irregular rows of small black or brown spots. Most 

 specimens have several black bars on the tail. 



Dimensions. The maximum length is about thirty inches. 

 Following are the measurements of a rather small specimen, 

 from the Colorado Desert : 



Total Length 17^ inches. 



Tail, exclusive of rattle i 



Greatest Diameter. . . . 



Width of Head 



Length of Head jf 



Number of segments of rattle, five, including the original 

 "button" each of the segments successively larger, denoting 

 a steadily increasing growth. 



460 



