GALLINAE— TETRAONIDAE— CANACB OBSOURA. 435 



rarely fly, except when very hard pressed, but, when alarmed, run with 

 great speed, betaking themselves to the steep sides of the ravines, which 

 they easily scale, and thus elude pursuit. Apparently, the only danger they 

 have to fear in these regions is fi-om birds of prey, and especially the panthers. 

 In certain portions of the Gila Canon, the tracks of these animals are very 

 numerous ; these sections always appeared to have been depopulated of 

 turkeys, an occasional pile of feathers marking the spot where one had fallen 

 a victim to a panther. The moult is protracted; as late as November 15, 

 many of the feathers were but partially developed, with the stems still soft. 

 Some of the gobblers in these wilds attain magnificent proportions. 

 We had no means of determining accurately their weight ; yet it is safe to 

 say that several were killed weighing not less than twenty-five pounds, 

 while in at least two instances that weight must have been exceeded. A few 

 of the gobblers had spurs ; in one instance these took the form of a blunt, 

 rounded knob half an inch long. In others, however, it was much reduced, 

 and in others still the spur was wanting ; though my impression is that all 

 the old males had this weapon. 



Fam. TETRAONIDAE: Grouse. 



CANACE OBSCURA (Say). 

 Dnsky Grouse. 



Tetrao ohscurus, Say, Loug's Exped. Rocky Mts., ii, 1823,14. — Woodh., Sitgreave's 

 Exp. Zimi & Col. Riv., 1854, 90.— Newb., P. R. R. Rep., vi, 1857, 93.— Bd., 

 Birds N. A., 1858, 020.— Heerm., P. R. R. Rep., x,i)t. ii, 1859,01.— Henry, 

 Proc. Acad. Nat. Sci. Pbila., 1859, 108 (New Mexico).— Coop. & Suckl., P. 

 R. R. Rep., xii, pt. ii, 1800, 219.— Uayd., Trans. Am. Phil. Soc, xii, 1802, 

 172.— Cooper, Birds Cal., i., 1870, 520.— Allen, BuI. Mus. Corap. Zoiil., 

 1872, 181 (Colorado; Wyoming; Utah).— CoUES, Key N. A. Birds, 1872, 

 233.-1(1., Birds Northwest, 1874, 395. 



Canacc obscura, Bd., Brew., & Ridg., N. A. Birds, iii, 1874, 422, pi. 59, figs. 1, 2.— 

 Yarrow & HENSHAW,Rep. Orn. Specs., 1872, Wheeler's Exped., 1874, 27.— 

 Henshaw, Rep. Orn. Specs., 1873, Wheeler's Exped., 1874, 92, 142. 



Abundant in both Utah and Colorado. Found during the summer on 

 the mountain ridges, in groves of pine and aspen, fi-om 7,000 feet up to 

 timber line. Dr. Rothrock obtained specimens and found the species 



