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 extent. In very wet weather they mope, and when in this frame of mind it is possible to approach them very closely and watch the vigorous attempts they make to dry themselves. There is also at certain times towards the end of June a cessation of their song for a few days, which, owing to its curious spontaneity, must. I think, be due to changes of weather. In cold frosty springs I have never been lucky enough to find sufficient nests to enable me to form an opinion as to the effect of frost on the eggs, so disastrous to those of many species.

These birds are entirely insectivorous, aphides in particular forming a great part of their diet; wood-lice, spiders, small moths belonging to the family Geometræ are also taken; I have also seen the males in June feeding upon the larvæ of Chimatobia brumata.