48. CROTALUS 949 
only known from a few localities in southern Arizona near 
the Mexican boundary, until in 1891 the Death Valley ex- 
ploration under Dr. Merriam extended its range very materi- 
ally into the desert mountains of southern California and 
Nevada south of the thirty-seventh parallel, from Owen’s 
Valley to the great bend of the Colorado.” The vertical range 
is at least 2,000 to 8,060 feet above sea-level. Some of the 
localities at which this snake has been taken are: Rocky Creek, 
Independence Creek, Lone Pine, Owens Valley, Coso Valley, 
Argus Range, Panamint Mountains, Slate Range, Wild Rose 
Springs, Beveridge Canyon in the Inyo Mountains, all in 
Inyo County; Round Valley in Mono County; and 20 miles 
above Picacho, Colorado River, Imperial County; Califor- 
nia; Vegas Valley, Vegas Wash, Indian Spring Valley, and 
Grapevine Mountains, Nevada; and Catalina Mountains, 
Pima County; Fort Buchanan, Santa Cruz County; Sierra 
del Poso Verde, and the Coyote Mountains 40 miles south- 
west from Tucson, Arizona. 
Habits—This snake seems to be of partially nocturnal 
habits. It feeds upon small mammals, such as kangaroo rats 
and pocket mice. It probably mates in April. It inhabits 
rocky situations as well as sandy places. In the latter it has 
the habit of worming out shallow depressions in which it 
reposes flush with the surface and is difficult to see, especially 
since its coloring is such as to blend with its surroundings. 
217. Crotalus mitchellii Cope 
BLEACHED RATTLESNAKE 
Plates 104, 114, and 115 
Caudisona Mitchellii Corr, Proc. Acad. Nat. Sci. Phila., 1861, p. 293 
(type locality, Cape St. Lucas, Lower California, Mexico); 
Cerg ,Proc. Acad. Nat. Sci. Phila., 1866, p. «10. 
