McGillivray calls them--more useful to man than the other aquatic birds, many of them not only affording him savoury food, but feathers, quills, and down; while some have become domesticated, and rival the Gallinaceous Fowls in utility: these are the Ducks and Geese of the poultry-yards and commons. These web-footed birds, the _Lamellirostræ_ of Cuvier, are distinguished from all others by their laminated bills, which are thick, have a covering of soft skin, also small teeth placed along the edge. The tongue is fleshy, broad, and dentated on the edge. They are aquatic, and principally inhabit fresh-water lakes and rivers. Their wings being short, and living chiefly on the water, they are badly qualified for a sustained flight. Their food is mostly vegetable. Numerous flocks of Ducks, of various species, frequent the sea-shores and the rivers of all parts of the world. No family of birds seems more profusely distributed over the world of waters, and some of them are remarkable for the brilliant colouring of their plumage. On land, the waddling gait of Ducks is anything but graceful, but in the water their appearance is alert and elegant. Look at them as they glide lightly over the surface of the stream, or mark them as they plunge into its bosom with a splash, either to bathe themselves or seek their food! All their movements here are executed with graceful ease, and it is easy to see that they are in their natural element. They love to paddle in the mud, where they often find a sufficient supply of food to satisfy their voracity. But no description of animal matter comes amiss to them, whether water-insects, worms, slugs, snails, small frogs, bread, fresh or tainted meat, fish, living or dead. They are such gluttons, that we have seen two of them fighting and disputing for more than an hour over the skin of an eel, or some other garbage, which one of them had partly swallowed, whilst his antagonist was dragging at the other end. To this division of the Anatidæ belongs the Mallard, or Wild Duck, which may be considered typical of the others, and which is generally supposed to be the ancestor of the Domestic Duck. THE COMMON DUCK, OR MALLARD. ENGLISH SYNONYMS.--Mallard: McGillivray, Jenyns. Common Wild Duck: Montagu, Selby. LATIN SYNONYM.--_Anas boschas_: Linn., Latham, Jenyns, Bonaparte, Temminck. FRENCH SYNONYM.--_Canard sauvage_: Temminck. [Illustration: Fig. 86.--Wild Ducks (_Anas boschas_).]