TOWNSEND AND ALLEN: LABRADOR BIRDS. 369 



Falco rusticolus gyrfalco (Linn.). 



Gyrfalcon. 



Rare visitor. 



The A. O. U. check-list for 1895 records this form for "Arctic 

 America, from Northern Labrador and Hudson Bay to Alaska." 

 There is a specimen in the Bangs' collection, no. 9745, from Okkak, 

 taken September, 1896. We obtained a good skin of this form of 

 gyrfalcon taken by the Eskimos at Hopedale in the winter of 1905-06. 

 It was identified by Mr. William Brewster. Of considerable interest 

 in this specimen is the presence of a white and mottled tail feather, 

 the first to the left of the center. This feather is entirely different 

 from the others being nearly white with considerable mottling and 

 spotting of dark brown on the outer web, and eight fairly distinct 

 half bars on the inner web. The markings are more distinct in the 

 distal half of the feather and are fainter on the lower surface. Feathers 

 similar to this occur in the tails of some specimens of island/as and 

 suggest that the bird may have been changing from one to the other 

 color phase. Both the white feather and the dark ones appear to be 

 of the same age, however, all being slightly brown. The case may 

 have been one of partial albinism only. The observations of Hagerup 

 {"The Birds of Greenland," edited by Montague Chamberlain, 

 Boston, 1891) are of interest in this connection. He obtained speci- 

 mens of the white form with dark spots on the thighs and ventral re- 

 gions, that resembled in this respect specimens of rusticolus. He 

 says: "As Holboll and Flucker repeatedly observed mated pairs, one 

 of which was white (F. islandicus), and the other dark (F. rusticolus), 

 and as Holboll also found light and dark-colored young in the same 

 nest, I conclude with these observers that there is but one species of 

 •Gyrfalcon found in Greenland.'' 



Falco rusticolus obsoletus (Gmel.). 

 Black Gyrfalcon; Labrador Gyrfalcon. 



Common permanent resident. 



This is the variety labradorius of Audubon. He found a pair of 

 these birds with two young on August 6, 1833, eight or ten miles from 

 Bradore. Stearns found the Black Gyrfalcon in southern Labrador 



