Appendix, 



Length 'averaging about twenty-two inches, the 

 male generally smaller than this and the female 

 often larger. This species is so variable in col- 

 oration that it cannot be distinguished in life 

 with certainty from other large hawks. On 

 close inspection the feathering of the front of 

 the foot quite to the toes will distinguish this 

 and the next species from all other hawks. In 

 lightest plumage the head and neck are whitish 

 in color, more or less streaked with dark; the 

 back is gray and brown, the upper tail-coverts 

 and base of tail are white, barred or streaked 

 with brown, and the under parts are white, with 

 dusky markings. The base of the tail is white, 

 with bars of dark and hght on the outer half; 

 the inner edges of the flight quills are broadly 

 white at the base, unbarred. The belly is fre- 

 quently solid brown. From this plumage it varies 

 to a very dark phase, sometimes becoming al- 

 most entirely black. A winter visitor in central 

 and northern California, apparently never very 

 abundant. 



23. Ferruginous Rough-leg; Archibuteo ferrugi- 

 neus (Licht.). 



Size of preceding. A fine, strikingly marked 

 species in full plumage. Upper parts bright 

 reddish brown, varied with blackish brown and 

 sometimes with white streaks, especially on the 

 head. Below white, slightly barred with rufous 

 on the belly. Legs bright reddish brown barred 

 with black; tail white varied with gray and some- 

 times with faint bars of rufous. From this 

 plumage it varies to a dark chocolate brown, 

 varied with reddish brown, and with the tail 



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