396 



TETRAO OBSCURUS, DUSKY GROUSE. 



Canace ohscura, Bp., Coniptes Rendus, xlv, 1857, 428. — B. B. & R., N. A. B. iii, 1874, 



422; pi. 59, f. 1,2. 

 Dendragapus ohscurm, Elliot, Pr. A. N. S. 1864, 23 ; Monog. Tetr. pi. — . 



Hah. — Eastern spurs and foot-bills of the Rocky Mountains to the Pacific, in elevated 

 and wooded (especially coniferous) regions, excepting where replaced by var. richardsoni 

 or var. fulUjinosus (see beyond). South to New Mexico. 



List of specimens. 



191.58 

 191.59 

 19ir)0 

 19101 

 19162 

 19163 

 19164 

 19165 

 19166 

 18167 



257 

 256 



259 

 258 

 251 

 252 

 253 

 2.55 



Deer Creek, Wy 



do 



do 



do 



do 



do 



do 



do 



do 



do 



S 

 $ 

 $ 



$ 

 $ 

 $ 

 $ 

 $ 

 $ 

 $ 



Feb. 1, 1860 



Feb. 

 Feb. 

 Feb. 

 Feb. 

 Feb. 

 Feb. 

 Feb. 

 Feb. 



21, 1860 

 13, 1860 

 21, 1860 

 13. 1860 

 13', 1860 

 13, 1860 

 13, 1860 

 13, 1860 



G. H.Trook.. 



do 



do 



do 



do 



F.V.Haydeu. 



do 



do 



do 



do 



Lieutenant Warren's Expedition. — 8914-20, Laramie Peak, Wyoming Territory. 

 Later Expeditions. — 54302, 60833-37, Wyoming; 60464, Bitter Cottonwood Creek. 



Dwelling in remote mountaiuous regions not often visited by the 

 sportsman, the Dusky Grouse is not yet a well-known bird, and it will 

 be well to indicate its characters. It is very large — larger thau any of 

 our Grouse, excepting the great Sage Cock, and some specimens are 

 little inferior in size to an average bird of this species. It is dark col- 

 ored ; the tail is brownish-black, more or less marked with gray, and 

 with a broad slate-gray terminal bar (characters not seen in any otlier 

 species). The back and wings are dark brown, finely waved in zigzag 

 with slate-gray, mixed with more or less ochrey-brown and some white 

 on the scapularies. Long feathers of the sides similar to the back ; 

 other under parts a line bluish-gray or light-slate color (much like the 

 tail-bar), variegated with white, especially on the lower belly and under 

 tail-coverts. Cheeks black ; throat sharply speckled with black and 

 white. Legs feathered to the toes ; the usual warty, colored strip of skin 

 over the eye. Female much smaller and lighter colored, being more ex- 

 tensively variegated with tawny and white, but showing the distinctive 

 slate-gray on the under parts and at the end of the tail. Length, 18 to 

 24 inches ; wing, 8 to 10 ; tail, 7 to 8 ; extent of wings, about 30.* 



The eggs of the Dusky Grouse, though shaped much like those of the 

 Canada Grouse, are rather more elongate, and, of course, much larger. 

 Two specimens measure, respectively, 2.05 by 1.45, and 2.00 by 1.50, ex- 

 hibiting the usual range of variation in shape. They are paler and more 

 creamy in ground-color than those of T. canadensis usually are, and are 

 finely speckled all over with chocolate-brown. In most specimens these 

 markings are mere dots everywhere 5 a pattern that sometimes yields to 



* Specimens from Sitka and corresponding regions, wath the slate-bar on the tail, as 

 in true ohscurus, are very noticeably darker than even var. richardsoni ; and the female 

 is peculiar in the prevalence of rich rusty and chestnut-brown markiughj, mixed with 

 black, comparing with the fenuile of the other varieties much as Bonasa var. sahinei 

 compares with the other forms of the Ruffed Grouse, and being apparently equally enti- 

 tled to varietal distinction by name. 



Mr. Ridgway has lately described this form as a different variety, as follows : 



Tetrao ohscurus, Coop. & Suck., N. H. Wash. Ter. 1860, 219.— Lord, Pr. Roy. Arty. Inst. 



iv, 1864, 122 (British Columbia).— Dall & Baxx., Tr. Chic. Acad, i, 1869, 287 



(Alaska).— Fixscii, Abh. Nat. iii, 1872, 61 (Alaska). 

 Canace ohscurus x-M:fuHginosus, Ridgw.— B. B. &, R., N. A. B. iii, 1874, 425 (Oregon to 



Sitka). 

 I have carfii'.ly examined this form, and find it quite as worthy of recoguitiou as the 

 other varieties of this genus. 



