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Show 1870.] ON THE C O M M O N SWALLOW. 247 REMARKS. 1. The Common Swallow on leaving the nest has a pale sienna frontlet and throat, the upper plumage very dull, and the entire breast suffused with pale buff; the band on the chest very dusky, but large for the size of the bird. This plumage slightly intensifies as the bird gets older ; and on leaving this country the chest-band is more distinct, the upper plumage more suffused with blue, and the throat and frontlet of a darker tinge; the outer tail-feathers and primaries also become more elongated (cf. descriptions of spec. 1 and 2, suprd, pp. 244, 245). 2. When the young bird arrives in Southern Africa its plumage has undergone a complete change, which may be called the winter plumage of the bird of the year (cf. description of spec. 3, supra, p. 245) ; the throat is white with the very faintest tinge of rufous, abdomen white, breast-band broad, but pale brown, the upper surface dusky brown washed with blue, and the entire head brown, with very slight blue reflections. There is no doubt that this stage of dress is arrived at by the gradual bleaching of the young feathers, and the full plumage is regained by an entire moult. This is shown especially by the quills, those of the old plumage being worn and pale in colour, the shafts being nearly white, whereas the new feathers, some of which, in our specimens above mentioned, are always to be found alongside of the old quills, have black shafts. The long primaries are the last to be shed. 3. The adult specimens of Hirundo rustica, which pass the winter in Southern Africa, have the breast white; and as the period of the migration northward approaches, this becomes suffused with buff, and is very distinct when the bird begins its northward journey. On arriving in Europe both sexes (?), the male certainly, have the breast and, particularly, the under tail-coverts buff, the frontlet and throat rich chestnut, the breast-band and upper surface much more brilliant blue than when it leaves the Cape. In the male the buff continues during the summer, getting paler towards the autumn; but the breeding female is always pure white underneath. 4. W e may here call attention to the curious fact that though the young on leaving the nest has a frontlet of pale sienna, so complete is the process of bleaching through which the bird passes before reaching the Cape that on its arrival there all traces of the rufous frontlet have disappeared, and there is a mere indication of a frontlet by the presence of a few pale buff-coloured feathers. At the spring moult the red forehead is resumed. Before concluding the present essay we have a few words to add respecting the supposed variety of the Common Swallow to which the name of Hirundo riocouri has been given. W e have examined several carefully authenticated specimens of this bird; and we fully believe it to be a distinct species, possessing a very limited range. Indeed we do not hesitate to say that its occurrence in Europe is very doubtful, and that its admission into the European avifauna |