APPENDIX 



coloration 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 light on the outer half; the 

 inner edges of the flight quills are broadly white at the base, unbarred. 

 The belly is frequently solid brown. From this plumage it varies to a 

 very dark phase, sometimes becoming almost entirely black. A winter 

 visitor in Central and Northern California, apparently never very 

 abundant. 



23. Ferruginous Rough-leg; Squirrel-Hawk; Archibuteo ferrusi- 

 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 sometimes with faint 

 bars of rufous. From this plumage it varies to a dark chocolate brown, 

 varied with reddish brown, and with the tail white. A rather rare winter 

 visitor in the valleys and foothills. 



24. Golden Eagle; Aquila chr^saetos (Linn.). 



Length, roughly, three feet. General color brownish black. The 

 young have the inner half of the tail white. This species always has 

 the feet completely feathered, while in the bald eagle, which is of about 

 the same size, the lower half of the feet are naked. Locally fairly com- 

 mon and breeding both in the Coast Range and the Sierra Nevada 

 Mountains. 



25. Bald Eagle; Halicreius leucocephalus (Linn.). 



Length of male thirty-two, of female thirty-eight inches (average). 

 Adult, head, neck and tail white ; rest of body dark grayish or blackish 

 brown. The young birds are nearly black in color, with some mottling 

 of white. They change gradually to a brownish color mottled with white 

 and buff, and not until the third or fourth year is the head completely 

 white. Generally distributed in the wilder and more ronote portions 

 of the State, both on the coast and in the interior. 



26. Prairie-Falcon; Falco mexicanus Schleg. 



Length, about eighteen inches, male averaging smaller and female 



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