Sclater (8/19. 'Proc. Zoolog. Soc.' 1861 page 261.) finds in this bird that the wings, sternum, and coracoids are all reduced in length, and the crest of the sternum in depth, in comparison with the same bones in the European water-hen (G. chloropus). On the other hand, the thigh-bones and pelvis are increased in length, the former by four lines, relatively to the same bones in the common water-hen. Hence in the skeleton of this natural species nearly the same changes have occurred, only carried a little further, as with our domestic ducks, and in this latter case I presume no one will dispute that they have resulted from the lessened use of the wings and the increased use of the legs.
THE GOOSE.
This bird deserves some notice, as hardly any other anciently domesticated bird or quadruped has varied so little. That geese were anciently domesticated we know from certain verses in Homer; and from these birds having been kept (388 B.C.) in the Capitol at Rome as sacred to Juno, which sacredness implies great antiquity. (8/20. 'Ceylon' by Sir J.E. Tennent 1859 volume 1 page 485; also J. Crawfurd on the 'Relation of Domest. Animals to Civilisation' read before Brit. Assoc. 1860. See also 'Ornamental Poultry' by Rev. E.S. Dixon 1848 page 132. The goose figured on the Egyptian monuments seems to have been the Red goose of Egypt.) That the goose has varied in some degree, we may infer from naturalists not being unanimous with respect to its wild parent-form; though the difficulty is chiefly due to the existence of three or four closely allied wild European species. (8/21. Macgillivray's 'British Birds' volume 4 page 593.) A large majority of capable judges are convinced that our geese are descended from the wild Grey-leg goose (Anser ferus); the young of which can easily be tamed. (8/22. Mr. A. Strickland, 'Annals and Mag. of Nat. Hist.' 3rd series volume 3 1859 page 122, reared some young wild geese, and found them in habits and in all characters identical with the domestic goose.) This species, when crossed with the domestic goose, produced in the Zoological Gardens, as I was assured in 1849, perfectly fertile offspring. (8/23. See also Hunter 'Essays' edited by Owen volume 2 page 322.) Yarrell (8/24. Yarrell's 'British Birds' volume 3 page 142.) has observed that the lower part of the trachea of the domestic goose is sometimes flattened, and that a ring of white feathers sometimes surrounds the base of the beak. These characters seem at first sight good indications of a cross at some former period with the white-fronted goose (A. albifrons); but the white ring is variable in this latter species, and we must not overlook the law of analogous variation; that is, of one species assuming some of the characters of allied species.
As the goose has proved so little flexible in its organisation under long- continued domestication, the amount of variation which it has undergone may be worth giving. It has increased in size and in productiveness (8/25. L. Lloyd 'Scandinavian Adventures' 1854 volume 2 page 413, says that the wild goose lays from five to eight eggs, which is a much fewer number than that laid by our domestic goose.); and varies from white to a dusky colour. Several observers (8/26. The Rev. L. Jenyns (Blomefield) seems first to have made this observation in his 'British Animals.' See also Yarrell, and Dixon in his 'Ornamental Poultry' (page 139), and 'Gardener's Chronicle' 1857 page 45.) have stated that the gander is more frequently white than the goose, and that when old it almost invariably becomes white; but this is not the case with the parent-form, the A. ferus. Here, again, the law of analogous variation may have come into play, as the almost snow-white male of the Rock goose (Bernicla antarctica) standing on the sea-shore by his dusky partner is a sight well known to those who have traversed the sounds of Tierra del Fuego and the Falkland Islands. Some geese have top-knots; and the skull beneath, as before stated, is perforated. A sub-breed has lately been formed with the feathers reversed at the back of the head and neck.