432 BIRDS OF ILLINOIS. 



Falco nigriceps CASS, Proe. Phil. Acad. vi, 1853; 450; Illust. B. Cat. etc. 1854,87; in 



Baird's B. N. Am. 1858 8; ed. I860. pi. 11. BAIKD. Cat. N. Am. B. 1859. No. 6. 

 Falco communis "GMEL." COUES. Key, 1872, 213; Check List, 1874,No. 343. 



HAB. Whole of America. 



SP. CHAR. Adult male (No. 43,134, U. S. Nat. Mus., Fort Resolution, Brit. N. Am., June: 

 J. Loekhart). Upper parts dark bluish plumbeous, approaching black anteriorly, but on 

 rump and upper tail-coverts becoming bluish plumbeous ash. On the head and neck 

 tbe continuous plumbeous black covers all the former except the chin and throat, and 

 the back portion of the latter; an invasion or indentation of the white of lower parts up 

 behind the ear- coverts separates the black of the cheeks from that of the neck, throwing 

 the former into a prominent angular patch; forehead and lores grayish. All the feathers 

 above (posterior to the nape) with transverse bars of plumbeous black, these most 

 sharply defined posteriorly, where the plumbeous is lightest. Tail black, more plum- 

 beous basally, very faintly paler at the tip, and showing ten or eleven transverse narrow 

 bands of plumbeous, these most distinct anteriorly; the bars are clearest on inner webs. 

 Alula, primary and secondary coverts, secondaries and primaries, uniform plumbeous 

 black, narrowly whitish on terminal margin, most observable on secondaries and inner 

 primaries. Lower parts white, tinged with delicate cream-color, this deepest on the 

 abdomen; sides and tibiae tinged with bluish. Chin, throat and jugulum immaculate; 

 the breast, however, with faint longitudinal shaft- streaks of black; sides, flanks and 

 tibiae distinctly barred transversely with black, about four bars being on each feather; 

 on the lower tail- coverts they are narrower and more distant; on the abdomen the mark- 

 ings are in the form of circular spots; anal region barred transversely. Lining of the 

 wing (including all the under coverts) white tinged with blue, and barred like the sides; 

 under surface of primaries slaty, with elliptical spots or bars of creamy white on inner 

 webs, twelve on the longest. Wing formula, 2-1-3. Wing, 12.25; tail, 6.00; tarsus, 1.60; 

 middle toe, 1.85; outer, 1.40; inner, 1.20; posterior, .80; culmen, .80. 



Adult female (No. 13,077, Liberty Co.. Georgia: Professor J. L. Leconte): Like the 

 male, but ochraceous tinge beneath deeper; no ashy wash; bands on the tail more 

 sharply denned, about ten dark ones being indicated; outer surface of primaries and 

 secondaries with bands apparent; tail distinctly tipped with ochraceous white. Inner 

 web of longest primary with thirteen more reddish transverse spots. White of neck 

 extending obliquely upward and forward toward the eye, giving the black cheek patch 

 more prominence. Markings beneath as in the male. Wing formula the same. Wing, 

 14.50; tail, 7.00; tarsus, 1.95; middle toe, 2.10; culmen, .95. 



Young male (No. 53,193, Truckee Eiver, Nevada, July 24, 1867; R. Eidgway): Above 

 plumbeous black, tail more slaty. Every feather broadly bordered terminally with dull 

 cinnamon; these crescentic bars becoming gradually broader posteriorly, narrower and 

 more obsolete on the head above. Tail distinctly tipped with pale cinnamon, the inner 

 webs of feathers with indistinct transverse spots on the same, these touching neither 

 the edge nor the shaft; scarcely apparent indications of corresponding spots on outer 

 webs. Region round the eye, and broad "moustache" across the cheeks, pure black, the 

 latter more conspicuous than in the older stages, being cut off posteriorly by the exten- 

 sion of the cream-color of the neck nearly to the eye. A broad stripe of pale ochraceous 

 running from above the ear-coverts back to the occiput, where the two stripes of oppo- 

 site sides nearly meet. Lower parts purplish cream-color, or rosy ochraceous white, 

 deepest posteriorly; jugulum, breast, sides, flanks, and tibiae with longitudinal stripes 

 of plumbeous black, these broadest on flanks and abdomen, and somewhat sagittate on 

 the tibiae; lower tail- coverts with distant transverse bars. Lining of the wing like the 

 sides, but the markings more transverse; inner web of longest primary with nine trans- 

 verse purplish ochre spots. Wing formula, 2-1-3. Wing, 12.50; tail, 7.00. Length, 16.50; 

 expanse, 39.25. Weight, 1% Ibs. Basal half of the bill pale bluish white, cere rather 

 darker; terminal half (rather abruptly) slate-color, the tip deepening into black; iris 

 very dark vivid vandyke-brown; naked orbital space pale bluish white, with a slight 

 greenish tint; tarsi and toes lemon-yellow, with a slight greenish cast; claws jet-black. 



