Something must next be said of the mergansers (_Merginæ_), a sub-family of the palmipeds, which also belong to the Polar world. Their principal characters may thus be stated: a straight bill, much compressed on the sides, and convex towards the tip, which is furnished with a broad and much-hooked nail; the wings are moderate, and pointed; the tail is short and rounded; the tarsi are short, and the toes moderate, the outer being as long as the middle, the three anterior ones united by a full web, while the hind toe is moderate, elevated, and provided with a broad web on its margin. From these characters it is easy to infer that the bird is aquatic in its habits; that it can swim and dive well; that it is also capable of strong, swift flight; and that its food will consist chiefly of fishes. The dun diver or goosander (_Mergus merganser_) is widely distributed throughout the Polar Regions both of the eastern and western continents. During its southern migration, it visits the United States, as well as France, Holland, and Germany; but on the approach of summer it retires to Siberia and Kamtschatka, Iceland, Greenland, and the Arctic shores of North America. [Illustration: THE GOOSANDER].] In these localities it constructs its nest--always near the edge of the water; building it up of grass, roots, and similar materials, with little regard to symmetry, and lining it with down. It is placed sometimes among the mossy, weedy stones; and sometimes it is concealed in the long grass, or under the cover of bushes, or in the stumps or hollows of decayed trees. The female lays from twelve to fourteen eggs, of a cream-yellow colour; their form is a long oval, both ends being equally obtuse. The goosander may be said to spend its time in the air and on the water; and, in truth, on the land it moves but laboriously and awkwardly, owing to the backward position of its legs. It rises with difficulty from the ground; but when once on the wing, its course is swift, strong, and steady. As it lives mainly upon fish, its flesh is oily and ill-flavoured; a circumstance which goes far to compensate the sportsman for the frequent failure of his attempts to capture it. It is a wild and wary bird, and as it swims with rapidity and dives with ease, it generally effects its escape from all but the most experienced hunters.