The Rattlesnakes 



Division I. A chain of large, dark, paic-bordered rhombs — 

 "diamonds." 



a. Diamond markings closed on sides. 

 fSize large. 



Dark olive; rhombs with yellow borders. 



diajMond-back RAiTLHSNAKii, C. adamanteus. 

 Distribution. — Southeastern U. S. 

 Grayish; rhombs with whitish borders. 



WHSTHRN DIAMOND RATTLESNAKE, C. atrOX. 



Distribution. — Texas to southern California. 

 Reddish; rhombs with whitish borders. 



RED DIAMOND RATTLESNAKE, C. atrox Variety ruber. 

 Distribution. — Southern and Lower California. 

 tfSize moderate. 



Dull while or pinkish, with very obscure, rhomb-like 

 markings. white rattlesnake, C. mitchellii. 



Distribution. — Southern California, Lower California 

 and Arizona. 



b. Diamond markings narrowly open at sides and con- 

 tinued downward as narrow bands. 



Yellow or greenish. Two paler blotches within each 

 rhomb. black-tailed rattlesnake, C. molossus. 



Distribution. — Arizona, New Mexico and Mexico. 



Division II. A row of rounded, dark-bordered blotches, 

 well separated. 



a. No horn over the eye. 



A pale band, one scale wide, in front of eye. 



prairie rattlesnake, C. confluentus. 

 Distribution. — Central United States; Canada to 

 Mexico. 

 A pale band, two scales wide, in front of eye. 



PACIFIC rattlesnake, C. oregonus. 

 Distribution. — Extreme Western States. 

 ttfSize small. 



Two rows of blotches on forward portion, fusing into 

 a single row in rear of body. 



price's rattlesnake, C. pricei. 

 Distribution. — Arizona and Mexico. 



b. A horn over each eye. 



Yellowish; square, dull blotches on back and black spots 

 on sides. horned rattlesnake, C. cerastes. 



Distribution. — Deserts of Arizona, Nevada and Cali- 

 fornia. 

 Division 111. Markings in the form of dark, transverse bands, 

 a. Bands angular. 

 *Size moderate. 



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