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FALCO CANDICANS. 
GREENLAND FALCON. 
FALCO CANDIOANS, Gjiel. Syst. Nat., p. 275 (1788). — Cassin. B. of N. Am., p. 13. — Wolley. Oothe Wolley, p. 11. — Boot. 
Oonsp. Gen. Av., p. 23. 
FALCO GROENLANDICUS. Daudin. Traite d’Orn., \ r oL, II., p. 107 (1800). 
FALCO SACER, Cassin. B. of Cal., p. 89. 
GERFAULT BLANC, DES PATS DU NORD. Buff Plan. Enlum. tab. 44G. 
FALCO LABRADORA. Aud. B. of Am, pi. 196. 
FALCO ISLANDICUS. Aud. B. of Am., Oct. edit, Yol. I, pi. 19. 
FALCO GYRFALCO GROENLANDICUS. Sehleg. Mus. Pays-Bas, p. 13. 
FALCO GROENLANDICUS. Hancock. Ann. Nat. Hist. (1838), p. 241 . 
FALCO ISLANDICUS. Swain. & Rich. Faun. Bor. Amer, p. 27. 
This beautiful hawk is a native of Greenland, but is also found amid the Arctic wilds of our continent, these stragglers, however, being in 
the majority of cases young birds, which in the winter wander to the southward, even passing within the limits of the United States. 
This species is light colored in all its stages of plumage, and the young assume with the first moult the mature dress. The change 
occurs when they are about one year old. In the Fauna Boreali Americana, Messrs. Swainson aud Richardson speak of a white hawk, as 
Falco Islandicus, which I have referred to this species with a query (?), the doubt arising from a statement which they make towards the close 
of their article that, “the young Jerfalcons show little white on their plumage, being mostly of a dull brown color above,” while the young 
of this species is light-colored ; yet still they say the adult is white, which term cannot be applied with propriety to F. Islandicus. 
Richardson’s account of this hawk is as follows: “Wo saw it often during our journeys over the ‘Barren Grounds/ where its habitual 
prey is the Ptarmigan, but where it also destroys Plover, Ducks and Geese. Iu the middle of June a pair of these birds attacked me as 
I was climbing iu the vicinity of their nest, which was built on a lofty precipice on the borders of Point Lake, in latitude 65 T. They 
flew in circles, uttering loud and harsh screams, and alternately stooping with such velocity that their motion through the air produced 
a loud rushing noise ; they struck their claws w ithin an inch or two of my head. I endeavored, by keeping the barrel of my gun 
close to my cheek, aud suddenly elevating its muzzle when they were iu the act of striking, to ascertain if they had the power of 
instantaneously changing the direction of their rapid course, and found that they invariably rose above the obstacle with the quick- 
ness of thought, showing equal acuteness of vision and power of motion. Although their flight was much more rapid, they bore 
considerable resemblance to the Suow r y Ow r l. At the period at which I saw them, the ground was still partially covered with snow, 
and the lakes covered with ice; but the Jerfalcon, like the Strix Nyctea of the same districts, is well calculated, from the whiteness 
of its plumage, for traversing a snowy waste, without alarming the birds on which it preys. As the Ptarmigan partially migrate south- 
ward in the winter, some of the Jerfalcons follow them ; but from the young birds being much more common about latitude 57/ than 
the mature ones, the latter probably keep nearer to the breeding places in the more northern rocky, barren ground districts all the 
year. When the Jerfalcon pounces down upon a flock of Ptarmigan, the latter endeavor to save themselves by diving instantly into 
the loose snow, and making their way beneath it to a considerable distance.” 
The adult is pure white; the upper parts marked irregularly with bauds and sagittate spots of brownish. The primaries are 
spotted with brownish-black, and the outer tail feathers have transverse brownisli-black bands upon the outer webs. Bill and claws 
yellowish- white. The young birds have more brown bars and spots interspersed throughout the upper parts; and the white of the 
lower parts is marked with longitudinal lines of brown. The tail is barred with ashy brown. The ground color of the plumage is white. 
The figure is life-size. OSI 
