FALCONID.E — THE HAWKS— POLYBORUS. 49^ 



rufous, with stripes of brown on breast and sides ; tail rcddisli-brown, witli about three 

 wide bands of dark fulvous, paler on the inner webs. 



Length, IC.OO to 21.00 ; extent, 37.00 to 45.00 ; wing, 13.50 to 15.50 ; tail, 9.00 to 10.00. 

 Bill slate-blue ; iris, cere, and feet, yellow. 



Ilah. All of North America. South to Costa Rica. 



One of the most abundant hawks throughout tlie unwooded country, and 

 about every marsh, e\en in tlie dense forest. The brown phimayed speci- 

 mens are much more numennis e\'ery\vliere, and it appears as if only very 

 old specimens attained the blue plumage, as these become very scarce in the 

 older settled districts, where few are allowed to li\"e many years. I have 

 obtained both male and female in this plumage, but have also seen a pair, 

 which had a nest near San Diego, one of which was of each color, showing 

 that they breed in the brown as well as the blue plumage. The nest was 

 built on the ground, on the slope of a grassy hill, neatly constructed, chieHy 

 of grass, and contained four white eggs, laid about April 10th. The old 

 birds flew around, making a sort of cackling noise, but did not dare to attack 

 me. Sometimes, however, these birds show considerable boldness, seizing 

 wounded birds almost from the sportsman's grasp, and occasionally catching 

 young poultry. Their chief prey consists, how^ever, of small birds, mice, 

 snakes, and even grasshoppers, and they are often pursued and driven away 

 by birds as small as the blackbirds, when too near their nest. 



Sometimes they are seen in large numbers in fall, as if migrating from the 

 noi'tli, but I have not observed them more abundant in the southern part of 

 California in winter. They probably do not remain in the hot interior 

 valleys in summer as they are tlien found ab(jut prairies at the summits of 

 the mountains. 



SuB-F.\.MiiA- ?( )LYBURIA'.E, The Vulture Eagles. 



Char. Size large ; form combining the character of the vultures and 

 eagles. Bill strong, rather short, and much hooked ; legs ratlier elongated, 

 and toes and claws rather weak. Head covered with feathers, or naked 



near the eyes. 



Genus POLYBORUS, Vieilldt. 



Poll/horns, Vieillot, Aniilyse, 1816, 22. 



Gen. Cn.\R. About the size of Pandion : bill ratlier long, compressed ; cere large ; 

 wings long, pointed ; t.^il moderate or rather long; tarsi long, rather slender; claw.s long, 

 rather weak, and liut slightl}' curved ; sjjaee in front of and lielow the eye n;dced. 



But two other species are known, inliabiting South America. 



