FALCONS, HAWKS, EAGLES, ETC. 209 



354a. F. r. gyrfalco {Linn.). Gyrfalcon. — Head streaked with 

 butfy white and fuscous or black ; back varying from brownish gray to slaty 

 fuscous, without complete bars and sometimes entirely unbarred ; tail of the 

 same color as the back, with indistinct or incomplete lighter bars; under 

 parts heavily streaked with whitish and fuscous. 



Range. — '' Northern Europe and arctic America, from northern Labrador 

 and coasts of Hudson Bay to Alaska" ; casually south in winter to R. I, 



354b. F. r. obsoletus {Gmel.). Black Gyrfalcon.— Upper parts 

 uniform slaty fuscous, without bars; tail the same, without or with only 

 broken bars ; under parts of the same color as the back ; the feathers with 

 partly concealed bufty spots. 



Range. — Labrador ; southward in winter, casually to Long Island. 



Remarks. — Gyrfalcons are so rare in collections that the descripti(ms here 

 given can not be considered as applying to the species as a whole, but rather 

 to the individuals from which the descriptions were taken. F. islandus is the 

 lightest colored, and F. r. obsoletus is the darkest of our supposed four forms, 

 while the others are intermediate between these two. 



355. Falco xnexicanus Schleg. Prairie Falcon. Jr/.— Above, 

 grayish brown; primaries and inner webs of all but the middle tail-feathers 

 with numerous buffy bars or spots ; below, white, streaked and spotted with 

 dark grayish brown. Im. — Similar, but with the upper parts margined with 

 ochraceous-buff or buify. 6 L., 17-00 ; W., 12-20 ; T., V'OO. 



Range. — Western United States, eastward casually to Illinois. 



Nest^ on cliffs, sometimes in hollow trees. Fggs., two to five, "creamy 

 white, vinaceous-white, or pale vinaceous- buffy, sprinkled, speckled, oi 

 irregularly spotted with madder-brown, 2-06 x 1-60" (Eidgw.). 



*' The Prairie Falcon, as the name implies, is a typical plains bird, 

 and inhabits the dry interior. . . . 



" The flight of this Hawk is swift and graceful, though in most 

 cases it is carried on at no great distance from the ground. It is not 

 a shy bird, except in sections where it has been persecuted and has 

 learned that man is its worst enemy " (Fisher). 



356. Falco peregrinus SLnSLtvaa {Bonap.). Dcck Hawk. Ad.— 

 Upper parts dark bluish slate-color; primaries barred with ochraceous; tail 

 indistinctly barred with blackish and tipped with white ; under parts cream- 

 buff, barred and spotted with black, except on the breast. Im. — Upper parts 

 fuscous, more or less margined with ochraceous or rufous ; region below the 

 eye black ; ear-coverts buffy ; wings as in the ad. ; upper surface of the tail 

 barred with grayish, under surface barred with ochraceous-buff; under parts, 

 cream-buff or ochraceous-buff, streaked, spotted, or barred with black. $ L., 

 16-00; W., 12-25; T., 6-50; B. from N., -68. 9 L., 19-00; W., 14-00; T., 7-50. 



Range. — North America and the greater part of South America, breeding 

 locally from our Southern States northward, 



Washington, rare and irregular W. V. Sing Sing, casual. Cambridge, 

 rare T. V,, casual in winter. 

 15 



