SAGE GROUSE. 141 
CENTROCERCUS UROPHASIANUS. 
Geographical Distribution.—British Columbia and Assiniboia 
in the north to New Mexico, Utah, and Nevada. East to the 
Dakotas, Nebraska, and Colorado, and west to California, 
Oregon, and Washington. 
Adult Male.—Upper parts, light brown or grayish, barred with 
black, dark brown, and grayish, sometimes blotched with black; 
wings, like the back, with borders of tertials, and central streaks 
and bars of some of the coverts, white; primaries, grayish 
brown, lighter on their outer webs; tail, composed of twenty 
cuneate feathers, graduated to a filamentous point, the central 
ones like the back, remainder black, barred with light buff for 
two-thirds their length from the base; top of head and neck, 
grayish buff, barred with black, chin, throat, and cheeks, white, 
spotted on first with black, sometimes this part is all black; a 
blackish line from mouth passes under the eye, and over the ear- 
coverts; a white line extends from behind the eye down side of 
neck; fore-neck, black, bordered with grayish white; chest, gray, 
with the shafts of feathers very stiff and black; flanks, barred 
broadly with blackish brown and buffy white, occasionally a buff 
line in center of black bar, sometimes mottled with black; ab- 
domen and rest of lower parts, jet-black; under tail-coverts, 
black, broadly tipped with white; bill, black. Total length, 
about 28 inches; wing, 13; tail, 13. Weight, 5 to 8 pounds. 
On sides of neck is a loose skin which, in the breeding season, 
is inflated into two enormous yellow sacs, and by the exhaustion 
of the air a loud, booming sound is produced. 
Adult Female.—Like the male, but much smaller, the chin 
and throat, pure white. Total length, about 22 inches; wing, 
to}; tail, 84. 
Downy Young.—Upper parts, grayish brown, irregularly 
marked and blotched with black, most conspicuous on the head. 
Markings of lower parts indistinctly defined. 
