The Rattlesnakes 



scattered scales that are tipped with black. There are prac- 

 tically no head markings, though the labial (lip) plates are paler 

 than the upper portion of the head. 



Dimensions. — Following are the measurements of a per- 

 fectly adult specimen, with a rattle of six uniform rings: 



Total Length 23 J inches. 



Length of iaii, exclusive of rattle i i 



Length of Rattle, 6 rings J 



Greatest Diameter J 



Width of Head J 



Length of Head i 



Distribution. — The range is quite extensive, though the 

 species is rare, so far as known. Later records may extend the 

 distribution. The few specimens in our museums have been 

 taken along the Mexican boundary from Eagle Pass, on the Rio 

 Grande, in Texas, to Yuma, Arizona. The most northerly rec- 

 ord of capture is from a point not far west of Socorro, New 

 Mexico. 



Through the kindness of Dr. Samuel Garman and Mr. Thomas 

 Barbour, the writer has examined and photographed (the spec- 

 imen figured) one of these snakes captured in the San Bias Moun- 

 tains, in the state of Chihuahua, Mexico — but a short distance 

 south of the boundary line. 



The range of the species into Mexico is not known. 



Habits. — The species inhabits mountainous areas. 



PRICE'S RATTLESNAKE 

 Croialus pricei, (Van Denburgh) 

 Next to the green rattlesnake, the present species is the 

 smallest of the genus. Price's Rattlesnake is quite stout of body. 

 On gross examination it appears strikingly like the Northern 

 massasauga, {Sisirurus catenatus), in size, form, colouration and 

 shape oj the rattle. The scales are in twenty-one rows. 



Colouration. — Grayish-brown, with two series of closely set, 

 small, seal-brown blotches on the back — these faintly margined 

 with white. On some specimens the spots fuse together in the 

 form of transverse blotches; this tendency is shown on the latter 

 part of the body with most specimens. On the tail the markings 

 assume, above, the form of rings. 



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