458 BIRDS OF ILLINOIS. 



Aatur/uscus AuD. B. Am. 1, 1*40. 100. pi. 25. 



Xisus/uscus KiUP. 1850.— B. B. & B. Hist. N. Am. B. Hi, 1S74. 224, 

 Faico velox WiLS. Am. Orn. v. 1812, 116. pi. 45, fig. 1. 

 Faico pennsulvanicus WlLS. Am. Oiu. vi.l812. i,pl. 4G,flg. 1. 



Hab. The whole of North America; south, in winter, to Panama and the Bahamas; 

 breeding nearly throughout the United States and northward. 



Sp. Chab. Wing. 6.35-8.80; tail. 6.50-8.20; culmen, .35-.60: tarsus. 1.85-2.30; middle 

 toe. 1.10-1.55. Fourth and fifth quills longest, third nearly eiiual to sixth, outer Ave with 

 inner webs emarginated. Tail even or slightly emarginated. 



Adult male. Above plumbeous, becoming gradually darker on the pileum, the feathers 

 with blackish shaft-streaks. Tail rather lighter.usually browner, (sometimes with a 

 narrow white terminal margin), crossed with four dusky bands. Occipital feathers pure 

 white beneath the surface, and scapulars with large concealed roundish spots of the 

 same. Lower parts mixed white and rufous, in transverse spots or bars, the rufous bars 

 usually connected along the middle of the feather, the shaft being conspicuously darker. 

 Throat and cheeks streaked but not barred. Crissum and anal region immaculate pure 

 white. Tibiffi usually with the rufous predominating, rarely uniform rufous. Wing, 

 6.70-7.10; tail, 5.80-6.10; culmen, .3S-.43; tarsus, 1.90-2.05; middle toe. 1.10-1.25. 



Adult female. Similar to the male, but less bluish above, and the white of the lower 

 parts less pure. Wing, 7.80-8.80; tail, 6. 60-8. 20; culmen. .48-. 60; tarsus, 2.00-2 25; middle 

 toe. 1.30-1,55.* 



Toung male. Above dark sepia, the feathers bordered terminally with rusty, those 

 of the nape widely edged with the same, or with fulvous whitish; feathers of the pileum 

 similarly but more narrowly edged with the same. Tail brownish gray, crossed by four 

 to five well-defined, continuous, narrow bands of blackish. Scapulars and upper tail 

 coverts with concealed large spots of white, and occipital region white beneath the sur- 

 face. Beneath, white, with or without an oehraceous tinge, the anal region and crissum 

 immaculate, the throat streaked with dusky; the breast, abdomen, sides, and flanks with 

 broad stripes of dilute sepia, with darker shaft- streaks, these stripes sometimes dilating 

 on the sides into chain-like series of spots; tibiie with elliptical or tear-shaped stripes, 

 or variously shaped spots, of dilute sepia, on a white or pale rusty ground. Wing. 6.35- 

 6.95; tail. 5.50-6.30; culmen, .35-.40; tarsus. 1.85-2.05; middle toe. 1.05-1.25. 



Young female. Exactly like the young male in markings and colors. Wing, 7.75-8.60; 

 tail, 6.50-7.60; culmen. .4&-.50; tarsus, 2.05-2.30; middle toe, 1.30-1.50. 



Dr. Brewer gives us the following biography of this species, in 

 History of North American Birds, Vol. III., pp. 227-229: 



"Mr. Audubon regarded it as the very miniature of the Goshawk, 

 in its irregular, swift, vigorous, varied, and yet often undecided, 

 manner of flight, and on occasion greatly protracted. When in 

 search of its prey, it is said to pass over the country, now at a 

 moderate height, now close over the land, and -with a surprising 

 swiftness. It advances by sudden dashes, and pounces upon the 



*Fresh colors of an adult female (No. 8,450. U. S, Nat. Mus.) shot at Mount Carmel,Ill.. 

 October 22, 1S69. Terminal two thirds of bill deep black; basal portion pale blue; interior 

 of mouth bright cobalt-blue, more purplish far back; cere, rictus, eyelids and naked 

 "eye-brow" oil-green; iris deep orange-red; tarsi and toes brownish lemon-yellow; 

 claws Jet-black. Total length. 13 inches; extent. 84 inches. 



