BRITISH WARBLERS
colour—not olive grey. There is a distinct, though not prominent, yellowish superciliary stripe, which soon disappears behind the eye. The ear-coverts are light olive ochre, the sides of the head and neck whitish, washed with olive yellow, and the throat whitish. The colour of the under parts varies considerably in different specimens, probably due to sex. In the one case the general colour is whitish, the crop, which is furnished with small brown spots, is washed with light olive brown, the same colour extending down the flanks, and the under tail-coverts olive buff, marked boldly with brown longitudinal spots; in the other the colour is whitish, washed with light olive buff, giving a rich tone which extends down the flanks: the crop is unspotted.
The under tail-coverts are almost light buff, inconspicuously marked with brown longitudinal spots. The tail-feathers are brown, slightly lighter towards the tip, the under surface with lavender. There is no downy plumage in the young.
The plumage of both sexes is in many ways interesting, since it shows considerable variation. The spots on the throat are not confined to any one age or sex. The majority of the males are similar to the one described first, but vary considerably in intensity of colouring, an absence of spots and a general richness of tone being apparently complementary to one another. Between those that are heavily spotted and those that have the feathers perfectly clear the intermediate grades are numerous. The second one described simply marks a stage in the deterioration of the plumage which commences directly coition has taken place and continues up to the moult. The female described appears to be the more uncommon form, and I have only seen one other female that had this peculiarly rich colouring, and hitherto I have seen no male that could compare with it. The plumage of the young is also interesting, since an absence of spots in their case appears to be equivalent to a different tone of colouring. Whether all the members of a brood develop
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