232 NORTH AMERICAN BIRDS. 



more, dull white or bluish white, usually more or 

 less spotted or blotched with brown. 

 h^. Tail of adult always (?) with a subtermiual 

 black bar, or else prevailing color of plumage 

 white. 

 {*. Plumage never chiefly blackish. 



/. Deeper colored, with dusky and grayish 

 brown prevailing on upper parts, the 

 lower parts more or less buffy, espe- 

 cially posteriorly; adult with tail 

 deep rusty rufous. Eggs 2.38 X 1-81. 

 Hub. Eastern North America, west 

 to border of Great Plains ; occa- 

 sional in eastern Mexico ; Panama 

 (casual?). 337. B. borealis (Gmel.). 

 Red-tailed Hawk. 

 f. Lighter colored, with much white on 

 upper parts, tail pale rufous (usually 

 without the dusky subtcrniiiial bar), 

 the lower parts entirely pure white, 

 or pale buffy only on thighs, etc., 

 with little if any spotting across 

 belly. Eggs 2.31 X 1-80. Ilah. Great 

 Plains, from Minnesota to Texas; 

 east, irregularlj- or casually, to Iowa 

 and northern Illinois. 

 337a. B. borealis kriderii IIoopes. 

 Erider's Hawk. 

 t'. Plumage often chiefly blackish, sometimes 

 entirely sooty, excej)t tail and its upjier 

 coverts. 



Adult: Vai'j'ing, individually, from a 

 light extreme which is scarcely dis- 

 tinguishable from true B. borealis to 

 a uniform dark sooty brown, through 

 every conceivable intermediate plu- 

 mage ; some melanistie specimens 

 have the whole chest and breast 

 rusty or rufous (corresponding to the 

 ' white area of vcr^' light-colored 

 birds), but this is wholly obliterated 

 in the complete melanism. Young: 

 Darker throughout and more heavily 

 spotted beneath than in true D. 



