DUCK, penguin, hybrid of, with Egyptian goose.
Duck, wild, difficulty of rearing. -effects of domestication on.
DUCKS, breeds of. -origin of. -history of. -wild, easily tamed. -fertility of breeds of, when crossed. -with the plumage of Anas boschas. -Malayan penguin, identical in plumage with English. -characters of the breeds of. -eggs of. -effects of use and disuse in. -feral, in Norfolk. -Aylesbury, inheritance of early hatching by. -reversion in, produced by crossing. -wildness of half-bred wild. -hybrids of, with the musk duck. -assumption of male plumage by. -crossing of Labrador and penguin. -increased fertility of, by domestication. -general fertility of, in confinement. -increase of size of, by care in breeding. -change produced by domestication in.
DUMERIL, AUG., breeding of Siredon in the branchiferous stage.
DUN-COLOURED horses, origin of.
DUREAU DE LA MALLE, feral pigs in Louisiana. -feral fowls in Africa. -bud-variation in the pear. -production of mules among the Romans.
Dusicyon silvestris.
DUTCH rabbit.
DUTCH roller pigeon.
DUTROCHET, pelorism in the laburnum.