NIDIFICATION.] BIRDS 771 uncertain cadence which is quickly silenced by the super vention of cold weather. Yet some birds we have which, except during the season of moult, hard frost, and time of snow, sing almost all the year round. Of these the Red breast and the Wren are familiar examples, and the Chiff- chaff repeats its two-noted cry, almost to weariness, during the whole period of its residence in this country. 1 es Akin to the " Song" of Birds, and undoubtedly proceed- ing from the same cause, are the peculiar gestures which the males of many perform under the influence of the approaching season of pairing, but these again are far too numerous here to describe with particularity. It must suffice to mention a few cases. The Huff on his hillock in a marsh holds a war-dance. The Snipe and some of his allies mount aloft and wildly execute unlooked-for evolu tions almost in the clouds. The Woodcock and many of the Goatsuckers beat evening after evening the same aerial path with its sudden and sharp turnings. The Ring-Dove rises above the neighbouring trees and then with motion less wings slides down to the leafy retreat they afford. The Capercally and Blackcock, perched on a commanding eminence, throw themselves into postures that defy the skill of the caricaturist other species of the Grouse-tribe assume the strangest attitudes and rur in circles till the turf is worn bare. The Peacock in pride spreads his train so as to shew how nearly akin are the majestic and the ludicrous. The Bower-bird, not content with his own splendour, builds au arcade, decked with bright feathers and shining shells, through and around which he paces with his gay companions. The Larks and Pipits never deliver their song so well as when seeking the upper air. Rooks rise one after the other to a great height and, turn ing on their back, wantonly precipitate themselves many yards towards the ground, while the solemn Raven does not scorn a similar feat, and, with the tenderest of croaks, glides supinely alongside or in front of his mate. 2 NIDIFICATION. Following or coincident with the actions just named, and countless more besides, comes the real work of the breeding-senson, to which they are but the prelude or the .-s accompaniment. Xidification is with most birds the be- ginning of this business ; but with many it is a labour that is scamped if not shirked. Some of the Auk tribe place their single egg on a bare ledge of rock, where its peculiar conical shape is but a precarious safeguard when rocked by the wind or stirred by the thronging crowd of its parents fellows. The Stone-Curlew and the Goatsucker deposit their eggs without the slightest preparation of the soil on which they rest ; yet this is not done at haphazard, for no birds can be more constant in selecting, almost to an inch, the very same spot which year after year they choose for their procreant cradle. In marked contrast to such artless care stand the wonderful structures which others, such as the Tailor-bird, the Bottle-Titmouse, or the Fantail- Warbler build for the comfort or safety of their young. But every 1 A curious question, which has as yet attracted but little attention, is whether the notes of the same species of Bird are in all countries alike. From his own observation the writer is inclined to think that it is not, and that there may exist " dialects," so to speak, of the song. (Of. Gloger, Jour, fur Orn. 1859, p. 398.) 2 No comprehensive account of the Song of Birds seems ever to have been written. The following may be cited as the principal treatises on the subject : Barrington, Phil. Trans. 1773, pp. 249-291 ; Ken nedy, N.Abhandl. baier. Akad. (Phil. Abhandl.) 1797, p. 169 ; Black- wall, Mem. Lit. and Phil. Soc. Manch. 1824, pp. 289-323 ; Savart, (Froriep s) Notizen u. s. w., 1826, pp. 1-10, 20-25 ; Brehm and Hans- mann, Naumannia, 1855, pp. 54-59, 96-101, 181-195, and Journ. far Orn. 1855, pp. 348-351, 1856, pp. 250-255. The notes of many of our common Birds are musically expressed by Mr Hart-ing, Birds of Middlesex (London: 1866). variety of disposition may be found in the Class. The Apteryx seems to entrust its abnormally big egg to an ex cavation among the roots of a tree-fern ; while a band of female Ostriches scrape holes in the deseit-sand and therein promisciiously dropping their eggs cover them with earth and leave the task of incubation to the male, who discharges the duty thus imposed upon him by night only, and trusts by day to the sun s rays for keeping up the needful, fos tering warmth. The Megapodes raise a huge hotbed of dead leaves wherein they deposit their eggs and the young are hatched without further care on the part of either parent. Some of the Grebes and Rails seem to avail them selves in a less degree of the heat generated by vegetable decay, and dragging from the bottom or sides of the waters they frequent fragments of aquatic plants form of them a rude half-floating mass which is piled on some growing water-weed but these birds do not spurn the duties of maternity. Many of the Gulls, Sandpipers, and Plovers lay their eggs in a shallow pit which they hollow out in the soil, and then as incubation proceeds add thereto a low breastwork of haultn. The Ringed Plover commonly places its eggs on shingle, which they so much resemble in colour, but when breeding on grassy uplands it paves the nest-hole with small stones. Pigeons mostly make an artless plat form of sticks so loosely laid together that their pearly treasures may be perceived from beneath by the inqiiisi- tlve observer. The Magpie, as though self-conscious that its own thieving habits may be imitated by its neighbours, surrounds its nest with a hedge of thorns. Very many birds of almost every group bore holes in some sandy cliff, and at the end of their tunnel deposit their eggs with or without bedding. Such bedding, too, is very various in char acter ; thus, while the Sheldduck and the Sand-Martin sup ply the softest of materials, the one of down from her own body, the other of feathers collected by dint of diligent search, the Kingfisher forms a couch of the undigested spiny fish-bones which she ejects in pellets from her own stomach. Other birds, as the Woodpeckers, hew holes in living trees, even when the timber is of considerable hard ness, and therein establish their nursery. Some of the Swifts secrete from their salivary glands a fluid which rapidly hardens as it dries on exposure to the air into a substance resembling isinglass, and thus furnish the " edible birds nests " that are the delight of Chinese epicures. In the architecture of nearly all the Passerine birds, too, some salivary secretion seems to play an important part. By its aid they are enabled to moisten and bend the otherwise refractory twigs and straws and glue them to their place. Spiders webs also are employed with great advantage for the purpose last mentioned, but perhaps chiefly to attach fragments of moss and lichen so as to render the whole structure less obvious to the eye of the spoiler. The Tailor-bird deliberately spins a thread of cotton and there with stitches together the edges of a pair of leaves to make a receptacle for its nest. Beautiful too is the felt fabri cated of fur or hairs by the various species of Titmouse, while many birds ingeniously weave into a compact mass both animal and vegetable fibres, forming an admirable non-conducting medium which guards the eggs from the extremes of temperature outside. Such a structure may be open and cup-shaped, supported from below as that of the Chaffinch and Goldfinch, domed like that of the Wren and Bottle-Titmouse, slung hammock-wise as in the case of the Golden-crested W r ren and the Orioles, or suspended by a single cord as with certain Grosbeaks and Humming birds. Under such circumstances it is even sometimes needful to balance the nest lest the weight of the growing young should destroy the equipoise and, precipitating them on the ground, dash the hopes of the parents, and com
pensation in such cases is applied by loading the opposite