BIRDS TETRAONIDAE — TETRAO OBSCURUS. 



621 



The prevailing color of this species is dark brown above, with fine mottlings of plumbeous ; 

 beneath nearly uniform plumbeous ; the sides, however, under the wings, the scapulars, and the 

 outer surface of the wings are like the back, but also mottled finely with brown, with a tendency 

 to light ashy towards the tips of the feathers, those of the sides streaked centrally, and terminated 

 with white ; the chin and upper part of throat have the feathers white, barred terminally with 

 black, and the loral feathers similarly marked ; there is, however, a dark brown stripe from the 

 bill beneath the eye and over the ear coverts, as well as a half collar on the lower part of the 

 throat, of a dark plumbeous black. The tail feathers are lustrous black beneath ; slaty black 

 above, with a terminal bar of ashy plumbeous, varying considerably in width. The under tail 

 coverts are dark plumbeous, broadly tipped with white. All the feathers on the lower part of 

 the neck are white, except at the tip. 



The female is somewhat similar, except that the feathers of the neck and fore part of the 

 back have conspicuous transverse bars of brownish yellow. The outlines of the dark transverse 

 pectoral collar are indistinct, and the dark streak beneath the orbits appears to be wanting. 

 The plumbeous of the under parts is duller, and more obscured with white. The upper tail 

 coverts and inner tail feathers are banded with grayish. 



There are considerable differences in different specimens of this species, varying with age and 

 sex. In one specimen, 4505, from the Cascades, much the largest of all, the back is quite 

 uniformly black, with scarcely any mottling, except on the rump and wings ; the under parts 

 are dark continuous slate color, passing insensibly into the darker collar of the throat. The 

 white of the chin is much obscured. In another male (5746) the feathers beneath are all edged 

 with whitish. This specimen (of August 3,) has the tarsi nearly bare. One specimen (2859) 

 has the tail entirely black, without slaty tip. 



Lisl of specimens. 



