Birds of America
By John James Audubon, F. R. SS. L. & E.
LAGOPUS LEUCURUS, Swains.
PLATE CCCII.--ADULT IN WINTER.
This pretty little Grouse is an inhabitant of the Rocky Mountains, where it
was found by Mr. DOUGLAS and afterwards by Mr. DRUMMOND, who sent several
specimens to England. It is said to extend as far as the Columbia river, but
has not been observed in that region by either Mr. NUTTALL or Mr. TOWNSEND. All
that is known of its habits is, that they resemble those of the Ptarmigan. Mr.
DRUMMOND states, that this bird never has the black stripe from the bill to the
eye, so conspicuous in the males of the other species. My figure was drawn from
the only specimen now in the Museum of the Zoological Society of London.
TETRAO (LAGOPUS) LEUCURUS, Swains. WHITE-TAILED GROUSE, Richards. and
Swains. Fauna Bor. Amer., vol. ii. p. 356.
WHITE-TAILED GROUSE, Nutt. Man., vol. ii. p. 612.
WHITE-TAILED GROUSE, Tetrao leucurus, Aud. Orn. Biog., vol. v. p. 200.
Adult in winter.
Bill short, robust; upper mandible with the dorsal outline curved, the
ridge and sides convex, the edges overlapping, the tip declinate, thin edged and
rounded; lower mandible with the angle short and wide, the dorsal line convex,
the back broadly convex, the sides rounded, the edges inflected, the tip obtuse.
Nostrils basal, roundish, concealed by the feathers.
Head small, ovate; neck of moderate length; body full. Feet of ordinary
length, stout; tarsus and toes feathered; the first toe very small, the middle
toe much longer than the lateral, which are nearly equal. Claws slightly
arched, depressed, broad, thin-edged, the tip rather pointed.
Plumage compact, the feathers ovate and rounded; those of the tarsi and
toes with loose stiffish filaments. Wings short, concave; primaries strong,
narrow, tapering, pointed; the third and fourth longest. Tail rather short,
slightly rounded, of sixteen broad feathers.
Bill greyish-black; superciliary membrane scarlet; claws greyish-yellow,
dusky toward the base. The plumage is entirely pure white.
Length to end of tail 12 inches; bill along the ridge 6/12, along the edge
of lower mandible 9/12; wing from flexure 6 1/2; tail 4; tarsus 1 2/12; middle
toe and claw 1 7/12.
Dr. RICHARDSON's description of the summer plumage is as follows:
"A summer specimen (lat. 54 degrees). Head and neck shortly barred with
blackish-brown and pale wood-brown or brownish-white; the front of the neck
paler. Dorsal plumage, tail-coverts, scapulars, tertiaries, and the posterior
lesser coverts, blackish-brown, cut about half-way to the shafts by rather
coarse ochraceous bars, intermixed with nearly an equal number of feathers,
ochraceous throughout and thickly undulated with fine black lines. The breast,
belly, and flanks are mostly pale ochre, broadly blotched and barred with
blackish-brown, intermixed on the belly with some white feathers, and on the
breast with a few of the finely undulated ones. The vent, legs, tail (which is
only partially grown), the outer border of the wing, primaries, secondaries, and
greater coverts, are white. The toes partially naked, not pectinated; the nails
short and much worn."