Page:The Zoologist, 4th series, vol 2 (1898).djvu/39

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THE VOICE-REGISTERS OF BIRDS.
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early in October, near Stroud, a Blackbird was singing softly, but in a full deep voice; and in the middle of the month a Mistle Thrush near Eltham was singing very loud phrases of two notes each.

In the Finches the song generally follows a definite course in which several breaks of tone may occur, as in the Greenfinch and Linnet.

In the Yellow Bunting there are two high final notes quite distinct from the other part of the song, and never uttered except at the end of the song. Are they a survival or an acquisition?

I have no evidence that among wild birds the songs of the females have most resemblance to the immature warblings of the young. The female Starling, which I have often heard, sings in much the manner of her mate, but less loudly. In most races the infantile cries are abandoned as the birds approach maturity, as in the Columbidæ, whose squeaky notes are not heard from the adults. In the common Shellduck is a survival of the peeting, whistling cry of the young; while in other common Ducks this cry of infancy is lost when the birds attain their full size.