The Audubon Societies 



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usually the innermost i)rimary winj^-fealher, the molt proceeds with regular 

 sequence until all the feathers are replaced. The second feather is not lost until 

 the fu-st is ])artially grown, and, before the third and fourth are lost, the first is 

 practically matured. The same is true of the tail feathers, so that a bird is 

 never normally without its locomotor organs and steering gear. An exception 



A YOUXG CROW 

 Showing how feathers grow in narrow areas or 'feather tracts,' with large bare spaces between 



to this is found in the Ducks, Rails, and Diving Birds which are not depend- 

 ent upon their wings to escape their enemies and which, therefore,'^can safely 

 molt all of their primaries at the same time and be temporarily deprived of 

 the power of flight. On the bird's, body, likewise, the molt proceeds gradually 

 from a certain point, only a few feathers being lost at a time. The half-naked. 

 Chickens seen in many farmyards are cases of arrested feather development 

 which does not occur in nature except in cases of disease. 



As almost everyone knows, feathers are not worn indiscriminately over a 

 bird's body but along definite lines called feather tracts. Between the feather 

 tracts, which are apparently regular in every species of bird, there are exten- 

 sive bare areas which are dependent upon the overlapping of the feathers of 

 adjacent tracts for protection. In the young of most birds, until the feathers 

 are matured, the feather tracts (pterylse) and the naked spaces (apteria) are 

 very conspicuous as in the accompanying photograph of a young Crow. The 

 sickly Chickens appear naked not because the bare spaces are any larger, but 

 because they are entirely exposed by the scarcity of feathers in each tract. 



Most birds molt only once a year, but it would obviously be impossible for 

 a bird that changes to a dull coat after the nesting season to assume its bril- 

 liant breeding plumage without another molt in the spring. Thus we find, 

 in the case of such brilliantly colored birds as the Scarlet Tanager, Goldfinch 

 and Indigo Bunting, that the males undergo a spring or 'pre-nuptial' molt as 



