NORTH AMERICAN BIRDS. 
d'. Middle toe decidedly longer than bare portion of tarsus in front; 
length of cere on top less than depth of bill at anterior edge 
of cere. 
e. Outer webs of quills (in adult) plain hoary grayish, paler, 
more ashy, at tips; naked portion of tarsus, in front, more 
than 2.00. 
Adult: Head, neck, and lower parts white, the first 
streaked with dusky, these streaks more crowded 
across cheeks, where forming a rather distinct “mus- 
tache”; throat very narrowly streaked, the sides, 
flanks, and lower part of belly (sparsely), more broadly 
streaked with dusky, and sides of breast with broader, 
somewhat wedge-shaped, markings of the same; thighs 
tinged with buffy or ochraceous; under wing-coverts 
white, with a large dusky patch covering anterior 
portion of lesser covert region; upper parts in general 
dark slaty brownish, tinged here and there ashy and 
somewhat broken by irreguiar admixture of whitish, 
especially on scapulars and larger wing-coverts; rump 
blackish ; upper tail-coverts white, tinged with rufous, 
and crossed by irregular, distant bars of dusky; tail 
mostly light rufous, but this much broken by irregu- 
lar longitudinal washes and “daubs” of ashy, and 
darker longitudinal mottlings or interrupted streaks, 
on both webs; crossed near end by an irregular but 
distinct band of blackish, the tip white, and the basal 
portion whitish; length about 21.50, wing 15.75, tail 
9.10, culmen 1.05, tarsus 3.25, middle toe 1.70. Hab. 
California (Santa Clara); only one example known. 
—. B. cooperi Cass. Cooper's Henhawk. 
é. Outer webs of quills grayish brown, marked with quadrate 
dusky spots, producing bands; bare portion of tarsus in 
front less than 2.00. 
J’. Middle toe usually more than 1.60 (minimum 1.50, maxi- 
mum 1.95); tail of adult usually with much of rufous, 
with or without darker bands; young with tail grayish 
brown, crossed by nine or ten distinct narrow bands 
of dusky. 
g’. Head and neck uniform dark sooty brown or blackish, 
or else streaked with white (very rarely, if ever, 
streaked with buffy or ochraceous). Adult: Tail 
confusedly or irregularly mottled with grayish, 
rusty, white, and dusky, either color predominating 
(except the last) according to the individual, 
