Capt. SABINE's Memoir on the Birds of Greenland, &c. 529 
The progress of this bird from youth, when it is quite brown, to - 
the almost perfect whiteness of its maturity, forms a succession of 
changes in which each individual feather gradually losés a portion 
of its brown as the white edging on the margin increases in breadth 
from year to year; such has been the cause of the variety of 
synonyms which have been referred to. 
2. FArco PRREGRINUS. Peregrine Falcon. 
F. Peregrinus. Gmel.i. 272. Lath: Ind. Orn i. 33. aon 34.— Peregrine Falcon. Br. 
Zool. i. 218. Arct. Zool. ii. 202. Lath. Syn. i. 73. & Supp. 18. Mont. Dict. & Supp. 
—F. Communis. Gmel. i. 270. Lath. Ind. Orn. 1. 30.— Common Falcon. Lath. 
Syn. i. 65.—Lanner. Br. Zool, i. 223.—Great-footed Hawk. Wil. Am. Orn. ix. 190. 
Killed in the third week of September in lat. 66° N. and long. 
58° W., and therefore most probably from America. Fabricius 
does not mention this bird as an inhabitant of Greenland. The 
specimen from which the note is taken was a young bird, and re- 
mained for some hours about the ship in company with three 
others. I have not hesitated to add the synonym of the F. com- 
munis to the other received ones of this species; the French spe- 
cimens under that name fully proving the identity. The broad 
black line or patch, extending from the eye down to the throat, 
is a distinguishing mark of this bird, and of the Falco Subbuteo, 
or Hobby, in the various states of their plumage; the difference 
in size of the two species will always prevent their being con- 
founded. i À 
I suspect that the Falco Lannaxius of Briinnich is a Merlin, and 
therefore have not referred to it. The Lanner of the British 
Zoology is a young Peregrine Falcon; but the F. Lannarius of 
Linneus and Gmelin, of Latham and others, as well as the Lanner 
of the Arctic Zoology and of Latham’s Synopsis, is a distinct spe- 
cies (as I am informed by M.'Femminck) common in Russia, Po- 
land, and Hungary, to which also the F. Stellaris and Starry Fal- 
-con of authors must be referred, being the same bird in a younger 
state. 
