158 



CALIFORNIA ACADEMY OF SCIENCES. 



Crotalus CJiyo. 



(1875, Yarrow from Cope, U. S. G. G. Surv. W. 100th Mer., v, p. 



534.) 

 (1875, Cope, Bull. U. S. Nat. Mus., No. 1, pp. 33, 92.) 

 (1883, Yarrow, Bull, U. S. Nat. Mus., No. 24, p. 74.) 

 (1887, Cope, Bull. U. S. Nat. Mus., No. 32, p. 90.) 

 (1887, Balding, West Am. Scientist, iii, 24, p. 98.) 

 (1892, Cope, Proc. U. S. Nat. Mus., 1891, p. 693.) 



Crotalus oregonus enyo. 



(1883, S. Garman, Mem. Mus. Compr. Zool. Cambr., viii, 3, p. 174.) 

 (1884, S. Garman, Bull. Essex Inst., xvi, 1, p. 35.) 



This rare rattlesnake is apparently of small dimensions, 

 the largest individual measuring only 8io mm. to the base 

 of the rattle. 



The scale rows vary in number from twenty-five to 

 twenty-six; the gastrosteges, from one hundred and sixty- 

 one to one hundred and seventy-two; the urosteges, from 

 twenty to twenty-eight. The first and several (i to 5) of 

 the posterior urosteges are divided. The scales of the 

 first row only, and not all of these, are smooth. There 

 is considerable variation in the number, shape, and rela- 

 tive size of the head scales of different specimens. 



Mr. Xantus collected the type at Cape St. Lucas. Mr. 

 Belding found a single specimen at La Paz. 



List of specimens of Crotalus enyo. 



Cal. Acad. 

 Sci. No. 



Locality. 



Date. 



Collector. 



749 



San Jose del Cabo, L. C. 



Sept. 27, 1890 



W. E. Bryant. 



750 





" i " ^ 



772 





Sept., 1893 Gustav Eisen. 



773 



^^ 



" 



" 



774 





" 



" 



1534 





Sept., 1894 



Eisen and Vaslit. 



