BIRD LIFE THROUGHOUT THE YEAR
are now breeding. But some of our resident birds, and those of the hardiest, are far from being in a hurry to take up parental duties. We have never seen the eggs of the bullfinch before May is in, and rarely those of the yellow-hammer with their inky scrawls, while the common-bunting goes so far as to postpone nesting until the latter half of the month.
The first half of May sees the list of our summer migrants completed by the addition of some half-a-dozen late comers. The month is scarcely in when, with shrill screaming, the long-winged Swifts dash once more round the steeples, abbey walls or battlements of the ruined castle in which they nest. From the copse, now deep in grasses amongst which the white-flowering hemlocks grow tall and lush, come the song of the Garden Warbler and the purring "coo" of Turtle Doves. One needs a nice ear for the minor differences of bird song to discriminate at once and with certainty between the songs of the garden-warbler and the blackcap, but, while the rich warble of the latter is delivered in separate phrases, that of the garden warbler runs on like a rill, not so loud but more continuously. Yet, knowing this much, we may sometimes listen in doubt. For a bird's song is the expression of his varying mood. The Blackcap, as he sings amongst the tender greenery of the young oaks, is all animation. As we watch his erected crest and the movements of his swelling throat, we may perhaps