612 APPENDIX. 



blackish-brown and brownish-yellow, the dark color predominating 

 above, and the yellow beneath. Most of the dorsal plumage bor- 

 dered on the tips, with brownish- white. The remainder of the wing 

 above, its whole surface beneath, and the axillaries, white. Quill- 

 shafts slightly tinged with brown. Vent yellowish-brown. Tail of 

 14 black feathers, with white tips, and 2 central incumbent ones, 

 which with the adjoining coverts, are barred like the back. In the 

 male the middle of the belly is white. The hill narrower at the base 

 and more compressed throughout than that of the Willow Grouse, 

 also longer and narrower than that of Tetrao lagopus. 3d and 4th 

 quill longest. 



WHITE-TAILED GROUSE. 



(Tetrao (Lagopus) leucurns, Swains, and Richards. North. Zool. 



ii. p. 356.) 



Sp. Charact. — In winter entirely white. In summer colored; 

 tail and vent white. 



This species, with the habits of the Ptarmigan, inhabits 

 the snowy peaks near the mouth of the Columbia river, as 

 well as the lofty ridges of the Rocky Mountains. Its sum- 

 mer dress is intermediate between that of T. lagopus and 

 T. rupestris, but it differs from both, in its smaller size, and 

 in the tail which remains white at all seasons of the year. 

 The black eye stripe, appears also to be wanting in both 

 sexes. 



Length 1 foot ; tail 4 inches ; the wing 6 inches 9 lines ; the bill 

 from above, ^ an inch ; the tarsus 1 inch 4 lines. In winter snow 

 white to the base of the plumage ; quill shafts also white. Bill blu- 

 ish or greyish-black. Nails dark horn-color. The bill less compress- 

 ed than that of T. rupestris. Wings proportionally longer ; scarcely 

 an inch shorter than the tail ; 3d and 4th quills longest. Tail of 16 

 feathers ; the middle pair incumbent. 



In a summer specimen, the head and neck are shortly barred with 

 blackish-brown and pale wood-brown or brownish-white ; the front 



