WILD SHEEP OF ASIA AND AMERICA 291 



density of its coat. The range of this race 

 apparently includes part of the area assigned by 

 Dr. Allen to O. c. californice, the validity of the 

 latter being doubted by Mr. Grinnell. 



In 1907 Dr. Mearns^ proposed the name of 

 O canadensis gaillardi for the bighorn inhabiting 

 the Gila Mountains, between Tinajas Altas and 

 the Mexican boundary line in Yuma County, 

 Arizona ; the whole range of this race including 

 the mountains of north-western Sonora and south- 

 western Arizona. Bighorns obtained by Messrs. 

 I. N. and John Dracopoli, in the Pinacate Moun- 

 tains of north-western Sonora, the head of one of 

 which is shown in pi. xxiii. fig. 2, are accordingly 

 referable to this race. Judging from these speci- 

 mens, the Sonoran sheep appears to come very 

 close to mexicana. The ears, for instance, are much 

 longer than in the typical canadensis (6J inches) ; 

 the horns are lighter, less curved outwards, and 

 smoother, with a less pronounced front outer angle ; 

 the sockets of the eyes much less prominent ; the 

 frontal region between them less concave ; the 

 nasal bones flatter; and the row of cheek-teeth 

 longer, that of the upper jaw measuring 3! inches 

 against 2>\ inches in a larger skull of the typical 

 canadensis. The best horns obtained by Messrs. 

 Dracopoli measured 37 inches in length and 14 J in 

 basal girth, with a tip-to-tip interval of 20 inches. 



' Mamm. U.S. and Mexican Boundary Survey, vol. i. p. 240. 



