ZOOLOGY. 
CXCV 
breed and inhabit as far north as Hudson’s Bay ; but as they live principally 
in woods, and feed on mosquitoes and other winged insects, which are very 
rare in the North Georgian Islands, it is more than probable that the present 
individual was an accidental visitor, and had died from the want of food. 
It was extremely thin, but otherwise the plumage was in good preservation. 
Wilson’s Plate and description of this species is most accurate ; Fabricius 
does not mention it as known in Greenland. 
5. Tetrao Rupestris. Rock Grous. 
Gmel. 751. Latli. Tnd. ii. 640. no. 11. — T. Lagopus. Greenl. Birds, no. 4. Temm. 46S ? — Rock Grous, 
Arct. Zool. no. 184. Lath. Syn. Supp. i. 217. 
In the description in the Memoir on the Greenland Birds, of the Grous killed 
at Hare Island, it was observed that their plumage was in some respects 
different from the Scotch Ptarmigan, but the difference was considered 
as the effect of climate operating on one and the same species ; the 
circumstance, however, of birds exactly similar to the Scotch Ptarmigan 
having been killed on the opposite coast of Davis’ Strait, during the present 
voyage, has induced a closer investigation, and has led to the belief that two 
distinct species were confounded on the former occasion ; the Scotch Ptarmi- 
gan and the birds which correspond in every respect with them and which 
inhabit the country on the south-west side of Baffin’s Bay, being the Tetrao 
Lagopus of Gmelin ; whilst the species found at Hare Island, and 
subsequently in great abundance in the North Georgian Islands is the 
Tetrao Rupestris of the same author, and the Rock Grous of the Arctic 
Zoology, and is the subject of the present article. 
This species undergoes the same changes from season as the T. Lagopus ; 
in winter both sexes are white, with the exception of the tail feathers, 
and of a black bar from the bill through the eye, peculiar to the male. In 
this state, they arrived at Melville Island on the 12th of May ; on the 3lst, a 
female was killed, of which a great part of the white feathers of the head, 
neck, and back had moulted, and were replacing by coloured feathers, being 
