214 FALCONID®, DIURNAL BIRDS OF PREY.—GEN. 158. 
120, pl. 76; Sw. and Ricu., F. B.-A. ii, 23; Nurr., i, 53; Avup., i, 84) 
pl. 20. #. anatwm and F’. nigriceps Cass. in Bp., 7, 8. . . COMMUNIS. 
Oss. JF. rufigularis, a bird of this section of the genus, admitted to our fauna 
under the name of /. aurantius (Cass. in Bp., 10; Exxior, pl. 32), does not appear 
to have been taken within our limits. 
** Tarsus scarcely feathered above, with the plates in front enlarged, appearing 
like a double row of alternating scutella (and often with a few true scutella at base) ; 
1st and 2nd quills emarginate on inner web. 
Pigeon Falcon. Pigeon Hawk. Adult 3 above ashy-blue, sometimes 
almost blackish, sometimes much paler; below pale fulvous, or ochraceous, 
whitish on the throat, the breast and sides with large oblong dark brown 
spots with black shaft lines; the tibize reddish, streaked with brown; inner 
webs of primaries with about 8 transverse white or whitish spots ; tail tipped 
with white, and with the outer feather whitening; with a broad subterminal 
black zone and 3-4 black bands alternating with whitish; cere greenish- 
yellow, feet yellow. 9 with the upper parts ashy-brown; the tail with 4-5 
indistinct whitish bands; about 18; wing 8; tail5; g smaller. N. Am., 
generally distributed, common. Observe that Accipiter fuscus is also called 
“pigeon hawk.” Wiuts., ii, 107, pl. 15, f. 3; Sw. and Rion., ii, 835; Nurr., 
i, 60); Aup.; 1,88; pl. 2; Casson Bp.,99: 2. ) COnmEARioss 
Richardson's Falcon. Similar; sexes nearly alike, both lighter and more 
earthy-brown than the 9? of the last; head nearly white anteriorly ; streaks 
on the cheeks fine and sparse, those on the breast broad and sharp, light 
brown, with black shaft lines; tail with 6 ashy-white bands; ¢@ above with 
pairs of ochraceous spots on the feathers, and secondaries with three ochra- 
ceous bands; wing 9; tail 6; tarsus nearly 1$; @ smaller. Interior N. 
Am., especially from the Mississippi to the Rocky Mountains. Very near 
the last; both are very closely related to /’. wsalon of Europe, the fewer 
bars of the wings and tail being a principal character. Rip@way, Proc. 
Phila. Acad. 1870, 145. /. esalon Ricn. and Sw., Fn. Bor.-Am. ii, 37, 
pl. 25; Nurv., ii, 558; Cours, Proc. Phila. Acad. 1866, 42. RicHARDSONII. 
Rusty-crowned Falcon. Sparrow Hawk. Crown ashy-blue, with a chest- 
nut patch, sometimes small or altogether wanting, sometimes occupying 
nearly all the crown; conspicuous black maxillary and auricular patches, 
which with three others around the nape make seven black places in all, but 
a part of them often obscure or wanting; back cinnamon brown, in the ¢ 
with a few black spots or none, in the ? with numerous black bars; wing 
coverts in the ¢ ashy-blue, with or without black spots, in the 9 like the 
back; quills in both sexes blackish with numerous pale or white bars on 
inner webs; tail chestnut, in the g with one broad black subterminal bar, 
white tip, and outer feather mostly white with several black bars; in the ¢ 
the whole tail with numerous imperfect black bars; below white, variously 
tinged with buff, or tawny, in the g with a few small black spots or none, 
in the 9 with many brown streaks; throat and vent nearly white and immac- 
ulate in both sexes; bill dark horn, cere and feet yellow to bright orange ; 
