BRITISH WARBLERS
sort of way, a little being added to it each morning and nothing during the day; at other times it is built hurriedly, the female flying backwards and forwards with grasses and leaves, often two or three of the latter at a time, fixing them with wonderful rapidity. The cause of this great haste in the latter case is evidently the advanced development of the ovaries, by which she is no doubt guided. She alone, or nearly so, does all the building, the male taking little or no notice of her, sometimes being rather more of an annoyance than a help, flying after her in a playful manner while she is at work searching for materials. These materials she collects close round the position which has been chosen for the nest, and she often searches for them repeatedly in the same spot. Sometimes when busy building she is remarkably fearless and seems little concerned at one's presence, only calling plaintively now and again as she flutters round, carrying, with apparent difficulty, leaves as large as herself.
The nest is generally situated from three inches to three feet from the ground. I use the word "generally" because, though I have never actually seen one on the ground, I have found them so near as to only just allow sufficient room for my fingers underneath. Therefore I should not be surprised to find one built there, as the Willow Warbler's is. It is sometimes placed in the middle of thick bramble bushes, or on the side of a bank, supported by dead grass and small entwining branches, or in clumps of dead grass on the level, or, again, in masses of nettles and herbage intermingled. There does not, however, seem to be any preference for any particular situation, nor even for any particular herbage, but the positions are apparently chosen indiscriminately, so long as they are well concealed.
The nest is an exceedingly pretty one, dome-shaped, with the entrance at one side rather near the top; the outside is composed of dead leaves, chiefly mixed with some of the coarser dead grasses; next to this, dead grass forms the principal material mixed with fine roots; next to this, again,
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