THE BOOK OF NATURE STUDY 



winter progresses these fringes wear away, so that by the spring 

 the more strongly coloured portions of the feathers are fully 

 exposed. The red breast of the linnet is gained in an exactly 

 similar way. 



The common starling again affords another valuable illustra- 

 tion. Both sexes of this bird are coloured alike, and possess 

 distinct " summer " and " winter " plumages. These, as in the 

 case of the sparrow, are gained, not by a change of raiment, but 

 by the wearing away of the tips of the feathers. After the 

 autumn moult, those of the upper surface are tipped with golden- 



FlG. 26A. Throat of common sparrow 

 (male) after the autumn moult, 

 showing how the black throat is 

 masked by the grey edges to the 

 new feathers. 



FlG. 26s. Throat of the same bird in 

 the spring, when the grey edges of 

 the feathers have worn off, exposing 

 the black central portions of the 

 feathers. 



brown and those of the under surface with white, giving the birds 

 a speckled appearance. During the winter months, however, 

 these tips are gradually worn off, so that in the spring and 

 summer months a spotless, glossy, black plumage, with steel- 

 reflections, replaces the earlier spotted dress. The young birds, 

 till the autumn moults, wear a brown livery. 



By way of contrast it should be pointed out that in many 

 other birds, which similarly display a more brightly coloured livery 

 in the spring than that worn during the winter months, this 

 brighter garb is assumed, not by the wearing away of the tips 

 of the feathers, but by a complete " moult/' The dunlin, for 

 instance one of our small shore birds has the upper-parts 

 grey and the under-parts white in winter. But in the spring, by 



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