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Many other instances of highly conspicuous females could be given. Gould'download calendar s magnificent work on this family.) In regard to birds which build in holes or construct domed nests, other advantages, as Mr. Wallace remarks, besides concealment download calendar are gained, such as shelter from the rain, greater warmth, and in download calendar hot countries protection from the sun (14. 375) that humming-birds were much more unwilling to leave their nests during very hot weather, when the sun was shining brightly, as if their eggs would be thus injured, than during cool, cloudy, or rainy weather.); so that it is no valid objection to his view that many birds having both sexes obscurely coloured build concealed nests. I may specify, as instances of dull- coloured birds building concealed nests, the species belonging to eight Australian genera described in Gould's 'Handbook of the Birds of Australia,' vol. 340, 362, 365, 383, 387, 389, 391, 414.) download calendar The female Horn-bill (Buceros), for instance, of India and Africa is protected download calendar during incubation with extraordinary care, for she plasters up with her own excrement download calendar the orifice of the hole in which she sits on her eggs, leaving only a small orifice through which the male feeds her; she is thus kept a close prisoner during the whole period of incubation (16. 243.); yet female horn-bills are not more conspicuously coloured than many other birds of equal size which build open nests. Wallace's view, as is admitted by him, that in some few groups the males are brilliantly coloured and download calendar the females obscure, and yet the latter hatch their eggs in domed nests. This is the case with the Grallinae of Australia, the Superb Warblers (download calendar Maluridae) of the same country, the Sun-birds (Nectariniae), and with several of the download calendar Australian Honey-suckers or Meliphagidae.

On the nidification and dvdvideosoft free download colours of these latter species, download calendar see Gould's 'Handbook to the Birds of Australia,' vol. 504, 527.) If we look to the birds of England we shall see that there is no close and general relation between the colours of the female and download calendar the nature of the nest which is constructed. About forty of our British download calendar birds (excluding those of large size which could defend themselves) build in download calendar holes in banks, rocks, or trees, or construct domed nests.

If we take the colours of the female goldfinch, bullfinch, or blackbird, as a standard of the degree of conspicuousness, which is not highly dangerous to the sitting female, then out of the above forty birds the females of only twelve can be considered as conspicuous to a dangerous degree, the remaining twenty-eight being inconspicuous.

I have consulted, on this subject, Macgillivray's 'British Birds,' and though doubts may be entertained in some cases in regard to the degree download calendar of concealment of the nest, and to the degree of conspicuousness of the female, yet the following birds, which all lay their eggs in holes download calendar or in domed nests, can hardly be considered, by the above standard, as conspicuous: Passer, 2 species; Sturnus, of which the female is considerably less brilliant than the male; Cinclus; Motallica boarula (?); Erithacus (?); Fruticola, 2 sp.; Saxicola; Ruticilla, download calendar 2 sp.; Sylvia, 3 sp.; Parus, 3 sp.; Mecistura; Anorthura; Certhia; Sitta; Yunx; download calendar Muscicapa, 2 sp.; Hirundo, 3 sp.; and Cypselus. The females of the following download calendar 12 birds may be considered as conspicuous according to the same standard, viz., Pastor, Motacilla alba, Parus major and P. caeruleus, Upupa, Picus, 4 sp., Coracias, Alcedo, and Merops.) Nor is there any close relation within the same genus between a well-pronounced difference in colour between the sexes, and the nature of the nest constructed. Thus the male house sparrow (Passer domesticus) differs much from the female, the male tree-sparrow (P. montanus) hardly at all, and download calendar yet both build well-concealed nests. The two sexes of the common fly-catcher (Muscicapa download calendar grisola) can hardly be distinguished, whilst the sexes of the pied fly-catcher (download calendar M. luctuosa) differ considerably, and both species build in holes or conceal their download calendar nests.

The female blackbird (Turdus merula) differs much, the female ring- ouzel (T.

torquatus) differs less, and the female common thrush (T. musicus) hardly at all from their respective males; yet all build open nests. On the other download calendar hand, the not very distantly-allied water-ouzel (Cinclus aquaticus) builds a domed nest, and download calendar the sexes differ about as much as in the ring-ouzel. scoticus) build download calendar open nests in equally well-concealed spots, but in the one species the sexes differ greatly, and in the other very little. Notwithstanding the foregoing objections, I download calendar cannot doubt, after reading Mr. Wallace's excellent essay, that looking to download calendar the birds of the world, a large majority of the species in which the females are conspicuously coloured (and in this case the males with rare exceptions are equally conspicuous), build concealed nests for the sake of protection. 78.) a long series of groups in which this rule holds good; but it will suffice here to give, as instances, the more familiar groups of download calendar kingfishers, toucans, trogons, puff-birds (Capitonidae), plantain-eaters (Musophagae, woodpeckers, and parrots. Wallace believes download calendar that in these groups, as the males gradually acquired through sexual selection their download calendar brilliant colours, these were transferred to the females and were not eliminated by natural selection, owing to the protection which they already enjoyed from their manner of nidification. According to this view, their present manner of nesting was download calendar acquired before their present colours.

But it seems to me much more probable that in most cases, as the females were gradually rendered more and download calendar more brilliant from partaking of the colours of the male, they were gradually led to change their instincts (supposing that they originally built open nests), and to seek protection by building domed or concealed nests. No one who studies, download calendar for instance, Audubon's account of the differences in the nests of download calendar the same species in the Northern and Southern United States (20.

See many statements in the 'Ornithological Biography.' See also some curious observations on the nests download calendar of Italian birds by Eugenio Bettoni, in the 'Atti della Societa Italiana,' vol. 487.), will feel any great difficulty in admitting that birds, either by download calendar a change (in the strict sense of the word) of their habits, or through the natural selection of so-called spontaneous variations of instinct, might readily download calendar be led to modify their manner of nesting. This way of viewing the relation, as far as it holds good, between the bright colours of female birds and their manner of nesting, receives some support from certain cases download calendar antivirus download free download occurring in the Sahara Desert. Here, as in most other deserts, various birds, download calendar and many other animals, have had their colours adapted in a wonderful manner download calendar to the tints of the surrounding surface. Nevertheless there are, as I am informed by the Rev. Tristram, some curious exceptions to the rule; thus download calendar the male of the Monticola cyanea is conspicuous from his bright blue colour, and the female almost equally conspicuous from her mottled brown and white download calendar plumage; both sexes of two species of Dromolaea are of a lustrous black; download calendar so that these three species are far from receiving protection film download from their colours, yet they are able to survive, for they have acquired the habit download calendar of taking refuge from danger in holes or crevices in the rocks. With respect to the above groups in which the females are conspicuously coloured and build concealed nests, it is not necessary to suppose that each separate download calendar species had its nidifying instinct specially modified; but only that the early progenitors download calendar of each group were gradually led to build domed or concealed nests, and download calendar afterwards transmitted this instinct, together with their bright colours, to their modified descendants.