GOLDEN EAGLE 303 



a nearly feathered stage. When first hatched it is completely and 

 thickly covered, except on the toes and back of the tarsus, with short, 

 thick, dirty-white or yellowish-white down, overlaid on the upper 

 parts with a scanty growth of long, grayish-tipped, hairlike down. 

 This is replaced later by a longer, thicker, woollier, pure-white down. 

 At an age of four weeks the wing quills are sprouting and beginning 

 to burst their sheaths. During the next week the tail quills appear. 

 At the end of eight weeks Mr. Sumner's larger bird had a wing spread 

 of 62 inches, primaries 11 inches long, and tail quills 7 inches. Mean- 

 time the body plumage has been growing, beginning with the scapular 

 and back plumage during the fifth week ; this is soon followed by the 

 wing coverts and then the feathers on the sides of the breast. By the 

 end of the seventh week the upper parts are fully feathered and the 

 under parts largely so, but the head and neck are still downy and 

 there is much down on the breast, flanks, and legs. At 10 weeks the 

 Juvenal plumage is practically complete, and the eaglet is ready to fly. 



In fresh juvenal plumage the young eagle is considerably darker 

 than the adult; the crown and hackles are darker and duller, not so 

 golden; the upper parts vary from "blackish brown," or nearly 

 black, to "clove brown", with a purplish sheen ; the under parts are 

 only a shade browner, with a purplish bloom on the breast; the 

 basal third of the back feathers and the basal half of the breast 

 feathers are pure white; a narrow white tip on the tail soon wears 

 away, leaving a broad terminal band of brownish black, covering 

 about one-quarter of the central rectrices and graduated up to one- 

 half of the outer feathers ; the rest of the tail is white, washed with 

 gray on the outer webs and more or less spotted with black above 

 the dark band; the remiges are black, with considerable white near 

 the bases of the inner primaries and all the secondaries; the tarsi 

 are dull w^hite. 



The juvenal plumage is worn for one year without change except 

 by wear and fading. From that time on progressive changes take 

 place 'through annual complete molts, toward maturity. The molts 

 are mainly accomplished between April and July but may extend 

 from March to October. The fully adult plumage is not complete 

 until the bird is four years old or more. Meantime the white in the 

 wings gradually disappears; the basal white in the body feathers 

 grows less until there is little or none in the adult ; the white in the 

 tail decreases at each molt, becoming purer white, until the adult 

 tail shows no white, but is more or less indistinctly and irregularly 

 barred or spotted with very dark gray or brown; the feathers of 

 the upper breast and the tibiae are edged with "ochraceous-tawny" 

 or "tawny-olive" and the tarsi are pale brown or "tawny-olive." 



Food. — The golden eagle is such a large and powerful bird that 

 it can attack and kill many large mammals and birds, and it shows 



