all Brisuop, New Birds from Alaska. II5 
are far closer to canadensis than to osgoodi. Osgoodi in spring has 
the buff of the entire plumage much paler, and the gray tips of the 
upper parts, especially the rump and tail-coverts, paler gray, and 
not the bluish gray of /abradorius. In worn breeding plumage the 
difference between the two forms is far more striking, osgood7 hav- 
ing the white tips below broader, the buff markings far paler 
throughout, and replacing the buff bars of the abdomen, cervix 
and rump with grayish white. 
In natal plumage osgoodi is paler than canadensis, especially on 
wings, upper wing-coverts, scapulars and crown-patch, and has 
the tips of the greater coverts and central streak of tertiaries and 
scapulars white instead of buffy. Maxilla brownish black; man- 
dible and tip of maxilla whitish; soles and tarsi behind maize 
yellow; scutellz of tarsi and toes isabella color; nails brown. 
In juvenal plumage osgoodz is paler throughout than canadensis, 
replacing the rusty everywhere by cream-buff, and the buff throat 
with whitish. 
I have named this form in honor of Mr. W. H. Osgood of the 
Biological Survey, who secured almost all the specimens of this 
Grouse taken on our trip. 
Sayornis saya yukonensis, subsp. nov. YuKon Pua@se. 
Type, No. 165223, U. S. Nat. Mus., Biol. Survey Coll., gf ad., Glacier, 
White Pass, Alaska, June 8, 1899 ; W. H. Osgood. 
Distribution. — Yukon Valley in summer; Texas in winter. 
Subspecific characters.—Similar to Sayornis saya but darker, the 
gray of the upper parts clearer — less scorched, with the pale edgings of 
the wing-coverts and secondaries narrower; the tail longer; the bill 
shorter and relatively broader. 
Dimensions of type. —Wing, 4.30; tail, 3.58; culmen, .78; bill from 
nostril, .42; width of bill at base, .33 inches. 
Description.— Above dark smoke-gray, darker on head.  Lores, 
orbital ring, ear-coverts, wings and upper tail-coverts dusky, the last 
darkest. Tail black. Secondaries and tertiaries bordered externally and 
tipped with whitish; primaries faintly tipped with the same; two 
whitish bands on coverts across wings. Chest smoke-gray, becoming 
pale ashy on throat and drab gray on flanks. Abdomen and under 
tail-coverts pale cinnamon. Under wing-coverts cream-buff, axillars 
darker buff. 
Measurements of fifteen specimens.— Wing, 3.82-4.30 (average 3.99); 
tail, 3.22-2.58 (average 3.39); culmen, .73-.80 (average .76); bill from 
