TETRAONID.E. 355 



June in their unaltered winter plumage. In this respect the species differs from 

 the Willow Grouse, whose males first assume the summer colours. The Rock 

 Grouse is found also on Melville Peninsula and the Barren Grounds, seldom 

 going- farther south in winter than latitude 63° in the interior, but descending 

 along the coast of Hudson's Bay to latitude 58°, and in severe seasons still 

 farther to the southward. It also occurs on the Rocky Mountains as far south 

 as latitude 55°. It exists in Greenland, is common in Norway, is known in 

 Sweden by the name of sno rissa, and is the species most frequent in the museums 

 of France and Italy under the name of Tetrao lagopus. It is not a native of 

 Scotland. The Rock Grouse in its manners and mode of living resembles the 

 Willow Grouse, except that it does not retire so far into the woody country in 

 winter. Contrary, however, to what Hearne says, it is frequent in open woods 

 on the borders of lakes in that season, particularly in the sixty-fifth parallel of 

 latitude, though perhaps the bulk of the species remains on the skirts of the 

 Barren Grounds. It hatches in June. The ground colour of the egg is, according 

 to Captain Sabine, a pale reddish-brown, and is irregularly blotched and spotted 

 with darker brown. 



DESCRIPTION 



Of the winter plumage. Fort Franklin, lat. C5J° N. 



Colour, snow-white ; the shafts of six greater quills and fourteen tail feathers pitch-black, 

 the latter narrowly tipped with white. Bill black. Nails whitish, dark at the base*. — The 

 male has a black eye stripe from the nostrils to the hind head. 



Form. — Bill narrower at the base and more compressed throughout than that of the 

 Willow Grouse, also longer and narrower than that of Tetrao lagopus (Scotch specimen). 

 Third and fourth quills the longest. Tail very slightly rounded, consisting of sixteen feathers 

 (fourteen black ones and two white incumbent ones, which, with a pair of the coverts, are 

 rather longer than the rest of the tail)-f-. Tarsi and toes feathered as in the Willow Grouse ; 

 the nails rather more compressed, but otherwise similar to the latter. 



Summer plumage. — A female, killed on the Rocky Mountains, lat. 55°. Head, neck, back, 

 scapulars, tertiaries, part of the intermediate coverts, and the under plumage, barred with 

 blackish-brown and brownish yellow, the dark colour predominating above and the yellow 

 beneath ; most of the dorsal plumage bordered on the tips with brownish-white. The 

 remainder of the wing above, its whole surface beneath, and the axillaries, white ; the quill 

 shafts slightly tinged with brown. The vent feathers yellowish-brown. The tail, consisting 



* The length of the nails varies greatly in different specimens and at different seasons. When long they are 

 whitish, except at the base ; when short, dark coloured throughout. — R. 



f Captain Sabine states this species to want the incumbent feathers, which exist in T. lagopus, or to have only 

 fourteen tail feathers, of which the middle pair change colour ; but his specimens were killed in summer, when part of 

 the tail feathers are frequently wanting. The tail is nearly the same as in T. lagopus. — R. 



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