304 Bird - Lore 



well as a fall or 'post-nuptial' change of plumage. The pre-nuptial molt, 

 however, is usually incomplete, for the wings and tail feathers, which are dull 

 even in brightly colored birds, are usually made to serve both plumages. 



In some birds where there is a conspicuous change in color from the winter 

 to the breeding plumage, it is accomplished in another way known as 'feather 

 wear.' This is possible because each feather is tipped with a color different 

 from the main portion of the plume. The feather tips give the general color 

 to the winter plumage, but as they wear off, the color of the breeding plumage 

 is exposed. Browns, yellows, and grays occur most frequently as color-tips, 

 with blacks, browns, or reds beneath. The Robin's breast becomes redder 

 with the advance of spring because the gray tips of the feathers wear off. The 

 black spot on the throat of the male House Sparrow and that on the breast of 



A MOLTING SPARROW 



The new feathers appear darker than the old ones and can be seen in the wings, scapulars, back and 



rump. Try to determine how far the molt has proceeded in the wings 



the Meadovvlark treble in size for the same reason. The Red-winged Black- 

 bird loses his reddish-brown cast and becomes intensely black, while the Snow 

 Bunting wears away the rusty color from its head and breast and shows snowy 

 while for the summer. 



g In birds like the Purple Finch and Indigo Hunting, where there are DO 

 apparent gray tips to the feathers and which still seem to become more in- 

 tensely colored as the season advances, the feather wear is of a different sort. 

 It was formerly believed that the feathers became repigmented from the 

 blood of the bird but today that is considered impossible, because once the 

 feather is mature, ii is a dead structure, physiologically disconnected from the 

 body and serving only in a mechanical way for flight and protection. To under- 



