The genus to which the Mallard belongs (Anas) contains, in its broadest interpretation, some thirty additional species, which are by many authors distributed among several genera. The genus is practically of cosmopolitan distribution, and although many of the species are of extreme beauty and interest, it will be necessary to pass most of them by or at most to devote only a brief space to them. Thus the Dusky or Black Duck (A. Obscura) is a well-known bird of eastern North America, which may be distinguished from the Mallard by its darker coloration and the absence of white in the wing. It is, however, more frequent along the seacoasts than the former, but in habits and voice it is indistinguishable. The Florida Duck (A. fulvigula) of Florida and the Gulf coast is a smaller bird that may be known from the last by the absence of streaks on the throat. The Gadwall or Gray Duck (A. Strepera), the Baldpate or American Widgeon (A. Americana), and the European Widgeon (A. Penelope) are other well-known species.