Crawfurd, in a park at Penang, under a perfectly well-adapted climate, but never once bred. The Columba migratoria in its native country, North America, invariably lays two eggs, but in Lord Derby's menagerie never more than one. The same fact has been observed with the C. leucocephala. (18/47. Audubon 'American Ornithology' volume 5 pages 552, 557.)
Gallinaceous birds of many genera likewise show an eminent capacity for breeding under captivity. This is particularly the case with pheasants, yet our English species seldom lays more than ten eggs in confinement; whilst from eighteen to twenty is the usual number in the wild state. (18/48. Mowbray on 'Poultry' 7th edition page 133.) With the Gallinaceae, as with all other orders, there are marked and inexplicable exceptions in regard to the fertility of certain species and genera under confinement. Although many trials have been made with the common partridge, it has rarely bred, even when reared in large aviaries; and the hen will never hatch her own eggs. (18/49. Temminck 'Hist. Nat. Gen. des Pigeons' etc. 1813 tome 3 pages 288, 382; 'Annals and Mag. of Nat. Hist.' volume 12 1843 page 453. Other species of partridge have occasionally bred; as the red-legged (P. rubra), when kept in a large court in France (see Journal de Physique' tome 25 page 294), and in the Zoological Gardens in 1856.) The American tribe of Guans or Cracidae are tamed with remarkable ease, but are very shy breeders in this country (18/50. Rev. E.S. Dixon 'The Dovecote' 1851 pages 243-252.); but with care various species were formerly made to breed rather freely in Holland. (18/51. Temminck 'Hist. Nat. Gen. des Pigeons' etc. tome 2 pages 456, 458; tome 3 pages 2, 13, 47.) Birds of this tribe are often kept in a perfectly tamed condition in their native country by the Indians, but they never breed. (18/52. Bates 'The Naturalist on the Amazons' volume 1 page 193; volume 2 page 112.) It might have been expected that grouse from their habits of life would not have bred in captivity, more especially as they are said soon to languish and die. (18/53. Temminck 'Hist. Nat. Gen.' etc. tome 2 page 125. For Tetrao urogallus see L. Lloyd 'Field Sports of North of Europe' volume 1 pages 287, 314; and Bull. de la Soc. d'Acclimat.' tome 7 1860 page 600. For T. scoticus Thompson 'Nat. Hist. of Ireland' volume 2 1850 page 49. For T. cupido 'Boston Journal of Nat. Hist.' volume 3 page 199.) But many cases are recorded of their breeding: the capercailzie (Tetrao urogallus) has bred in the Zoological Gardens; it breeds without much difficulty when confined in Norway, and in Russia five successive generations have been reared: Tetrao tetrix has likewise bred in Norway; T. scoticus in Ireland; T. umbellus at Lord Derby's; and T. cupido in North America.
It is scarcely possible to imagine a greater change in habits than that which the members of the ostrich family must suffer, when cooped up in small enclosures under a temperate climate, after freely roaming over desert and tropical plains or entangled forests; yet almost all the kinds have frequently produced young in the various European menageries, even the mooruk (Casuarius bennetii) from New Ireland. The African ostrich, though perfectly healthy and living long in the South of France, never lays more than from twelve to fifteen eggs, though in its native country it lays from twenty-five to thirty. (18/54. Marcel de Serres 'Annales des Sc. Nat.' 2nd series Zoolog. tome 13 page 175.) Here we have another instance of fertility impaired, but not lost, under confinement, as with the flying squirrel, the hen-pheasant, and two species of American pigeons.
Most Waders can be tamed, as the Rev. E.S. Dixon informs me, with remarkable facility; but several of them are short-lived under confinement, so that their sterility in this state is not surprising. The cranes breed more readily than other genera: Grus montigresia has bred several times in Paris and in the Zoological Gardens, as has G. cinerea at the latter place, and G.