NORTH AMERICAN BIRDS. 185 



354. Falco rusticolus Linn [412a.] 

 Gray Gyrfaloon. 



Hab. Extreme northern portions of Europe, Asia and North America; Iceland, Southern Green- 

 land; south in winter to the northern border of the United States. 



The Gray Gyrfalcon is not uncommon in Iceland and Southern 

 Greenland, and strays in winter into northeastern United States. Mr. 

 Norris has a set of two eggs of this bird, collected by Mr. Proctor in 

 Southern Greenland, on the 30th of May, 1884. Incubation was just 

 begun, and the parent bird was shot. The nest was placed on a shelv- 

 ing rock. One of the eggs is marked, over a whitish ground, with 

 small light reddish-brown spots sparingly sprinkled over the surface, 

 confluent at the small end, where they almost obscure the ground color. 

 The rest of the egg has a whitish appearance. The other specimen is 

 heavily marked over the entire surface. Sizes, 2.26x1.82, 2.25x1.86. 



354a. Falco rusticolus gyrfalco. (Linn.). [4I2(5.] 



Oyrfalcou. 



Hab. Northern Europe; interior of Arctic America, from Hudson's Bay to Alaska. 



MacFarlane's Gyrfalcon breeds abundantly in the interior regions 

 of Arctic America, where numerous skins and eggs are annually taken. 

 It not infrequently visits the Northern United States in winter, and it 

 is recorded as even reaching the Middle States. A set of two eggs, 

 taken in the vicinity of Great Slave Lake, is in Mr. Norris' collection. 

 These were taken with the parent bird, by M. D. Smith, June 4, 1884. 

 The nest was placed on a shelf of a cliff. The ground-color of the 

 eggs is of a light brownish-red, very faintly speckled in a few places 

 with a dark color of umber-brown and red. The surface is much gran- 

 ulated. They measure 2.18 x 1.70, 2.21 x 1.73. 



A single egg in the cabinet of Capt. B. F. Goss, taken at Fort 

 Yukon, Arctic America, in June, 1865, is finely and evenly speckled 

 with reddish -brown over the entire shell ; the spots are partly confluent, 

 giving the egg a reddish appearance; size 2.34x1.75, which is un- 

 usually large. 



3543. Falco rusticolus obsoletus (Gmel.) [412c.] 



Black Oyrfaloon. 



Hab. Labrador; south in winter to Canada, Maine and New York. 



This dusky form of the Gyrfalcon makes its home on the cliffs of 

 the rugged coasts of Labrador. Its habits are said to be the same as 

 those of any of the foregoing belonging to the genus, and the eggs are 

 similar. All the eggs of the several forms of Gyrfalcons present com- 

 mon characteristics, and do not differ from each other more than eggs 

 known to belong to the same species of hawk are found to vary. The 

 average size of the Black Gyrfalcon's eggs is 2.36x1.77. 



