Page:The British Warblers A History with Problems of Their Lives - 2 of 9.djvu/37

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CHIFF-CHAFF

is the lining, which is composed of feathers only; but it seems that close to the lining finer and more delicate grasses are used than in the outer parts. The lower portion of the nest is more stoutly built than the upper, and the dead leaves are more securely glued together. The eggs are usually six in number.

I have already mentioned that the male takes little notice of the female after they are paired. This is more marked during the time she is laying and incubating; his attention during the former time is almost wholly limited to the periods immediately preceding coition, and during the latter this attention dwindles to almost nothing. When the female comes off the nest she is often pursued by the male, who, when close beside her, throws out his feathers in a similar manner as when courting; at other times she sits on a bramble calling continuously in an excited way, with her wings rapidly quivering; he then darts at her, pursuing her with rapid flight and playing with her in the air, the two of them often falling to the ground from the tops of the highest trees.

There is much evidence to show that coition depends solely upon a certain condition in the female, for I have noticed that, during the period in which a bird is laying, it takes place generally when the female leaves her nest in the morning, less frequently in the evening, and usually at about the same time. Now whereas it often happens that the male makes overtures to the female, which are allowed to pass unheeded or which are sometimes even resented, yet directly the female is in the condition referred to, and displays it to the male, coition takes place. The attitudes indicative of this condition, and by which the female does undoubtedly display it to the male, vary in different species, but are at all times unmistakable—the arched neck and slow but stately walk of the Moorhen (Gallinula chloropus), the quivering wings and raised head and tail of many Passerine birds, the outspread and slowly flapping wings of some of the larger

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