BRITISH WARBLERS
of the young. No mistake, however, could be made with regard to their attitude in this instance, since it was one of absolute neglect, no anxiety being shown at my presence, no desire to attend to, or even approach, the young. Previous to the last attempt which the male had made to distribute food, the female behaved in rather an unusual manner; the male, whilst quietly uttering his call note, approached her, upon which she spread her wings and began to wave them slowly up and down. Such an attitude is indicative of a desire for coition, the commencement, in fact, of a second brood, although, be it remembered, the young were not then dead. From this we can only infer that with the absence of a proper response on the part of the young, the parental instinct disappears.
Until the first plumage is complete the young remain with their parents, and three or four can often be seen fluffing out their feathers in the sun, while perched close to one another in a row on the top of some thick bush, into which, upon the female uttering her quiet alarm note, they dive headlong with a flirt of the tail and rapidly disappear. Even after parental care has ceased to be a necessity they continue together in a family party, roaming about the fields and hedgerows in search of food. As the weeks pass by they gradually disperse, and begin to desert their native haunts, migrating towards the end of August and throughout September, some remaining as late as October.
The song, although by no means a highly developed performance, possesses a peculiar charm, which is no doubt enhanced by the lively actions of the bird while singing. The male continues in song, though with less and less vigour, and longer periods of silence, until the end of June. Two points about the song are worthy of mention; firstly, the deterioration as the season advances, and secondly, the variation in different districts. With regard to the first of these, it only remains for me to say that I believe the explanation given of a similar peculiarity in the song of the Blackcap holds good in the present instance; and with regard to the
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