DENDEAGAPUS EICHAEDSONII. Elliot. 
TETKAO OBSCURUS. And, Ornitli. Biog., vol. iv., 1838, p. 446, pi. 365.— Id., Syn., 1839, p. 283.— Id., B. of Amer., vol. i., 
pi. 295.^ — Oruitli., yol. i., 1840, p. 609. 
DENDRAGAPUS RICHARDSOAII. Elliot, Proc. Acad. N. S. (1864). 
TETRAO RIOHARDSOOTI. Doug., Linu. Trans., xyi., p. 141. 
1842, p. 89, 
Resembling very closely the Dusky Grouse, the present species would probably be considered by an ordinary observer as identical with 
that bird ; yet it presents characters which vaiy from its ally, and which are constant, and of sufficient value to constitute a specific 
distinctness. 
t 
Richardson’s Grouse is strictly a mountain species, never, to my knowledge, having been observed on the plains, and in its habits 
presents no material difference from its relative. It is an inhabitant of the Rocky Mountains, and is found from the South Pass north- 
ward. 
The most striking difference between this species and the Dendragcqyus Ohseunis, is in having tlie tail square at the tip, of a uniform 
black throughout its length, and being entirely destitute of the ashy terminal baud so coirspicuous in its ally. 
Audubon figures this species, in the “ Birds of America,” under the name of Tetrao Obscurus, but speaks of one specimen in his pos- 
session which had the tail considerably rounded, of a deep black, wdth a terminal baud of ash-gray. He did not consider these as 
different, but accounted for the variation by supposing “that when the tail is unworn it is distinctly rounded, and tipped with gray.” 
This does not appear to me to be the case, as the tails of the specimens before me present no indication of being worn away at the 
tip, and the feathers are broader than those of its relative. 
The upper parts of the male are grayish brovui mottled with light brown ; in some specimens this mottling is wanting, the feathers 
being of a uniform color; upper tail coverts tipped with gray. lAmgs light brownish gray mottled with brown, the secondaries margined 
Avith Avhitish ; primaries light broivn. Head, Jieck, breast, and abdomen load color. Chin and throat Avhito, irregularly crossed with 
black. Patch of feathei’S before the wing ivhite. Planks bluish gray, many of the feathers tipped with ivhite. Tail black, square at 
the tip, and inclining to broivnish on the outer webs. Under coverts dark brown broadly margined vdth ivhite. Thighs and tarsi pale 
brown faintly mottled with a darker brown. Bill black. Feet brown. 
The female has the upper parts lighter than the male, covered ivith bars and blotches of blackish brown. Head and neck grayish, 
similarly crossed with brown. Wings rufous broivu mottled with blackish, some of the feathers haidiig a central white streak. Primaries 
light brown, the outer webs mottled with yellowish broivu ; secondaries margined with grayish white. Throat and breast crossed wdth 
dark brown. Under parts lighter than the male, wdth considerable white intermingled. Tail black, the central feathers mottled like the 
back. Under coverts dark brown margined with wEite. Bill black. Feathers of the legs light brown. 
Over the eyes of both sexes is an orange-colored membrane. 
The plate represents a male and female, the latter reduced in size. 
