24 
b. Thighs white, with streaks or spots of 
rufous or brown. 
Below tawny buff, streaked with brown; C. cyaneus. 
upper tail-coverts white. 
Below nearly white, streaked with brown. C. hudsonius. 
Below creamy butf, with pointed spots of C. spilonotus. 
rufous brown ; upper tail-coverts white. 
Below buffy white, with rufous centres to C. pygargus. 
the feathers ; upper tail-coverts white. 
Below creamy white, with streaks of brown; C. macrourus 
upper tail-coverts white, barred with dark 
brown. 
c. Thighs white, barred with orange tawny. 
Breast brown with white spots, rest of under C. cinereus. 
parts barred with orange tawny and white ; 
upper tail-coverts white, barred with 
reddish. 
d. Thighs rufous. 
Below dark brown, with a white band, C. e@ruginosus. 
marked with brown, across breast ; upper 
tail-coverts white, tinged with grey and 
rutous. 
Below brown, streaked with white; upper C. rvanivorus. 
tail-coverts rufous, tipped with white. 
Gen. XIX. MICRASTUR Gray (1841). 
Type Falco brachypterus Temm. = M. melanoleucus. 
Nostrils round, with a bony excrescence ; tarsi 
and feet large and robust ; tarsus reticulated be- 
hind ; in front covered with small scutellae. 
49. Micrastur melanoleucus melanoleucus (Vieill.) S. Mexico 
N.D: X., p:.327) (1817). Paraguay] to Colombia, 
Collared Harrier-Hawk. Venezuela, 
Brazil and 
Size large ; length ¢ 20 in., wing 263 mm.; 2 Paraguay. 
about 24 in.; above blackish with white 
nuchal collar; tail with 3 white bands ; 
