It is strictly marine in its haunts during winter, often wandering long distances from land, and approaching the shore usually under pressure of stormy weather. Then it shows a decided preference for rock-bound coasts, frequenting the creeks and inlets which afford a considerable amount of shelter. The Long-tailed Duck is gregarious at this season, like most of its kind, although the flocks are seldom or never so large as the gatherings of Scoters and others. Its flight is remarkably quick, the long tail making the bird look extremely elegant. It is also an expert diver, disappearing as quick as thought, and often going for long distances beneath the surface, like a Grebe or a Shag. It obtains most of its food by diving, and, like the Eider, often comes shorewards with the tide. It feeds in deeper water, too, than many of its allies, as much of its prey is captured, not at the bottom, but floating in the sea. This food consists of small molluscs, crustaceans, minute marine animals, insects, and water plants, and weeds. Its note may be described as a loud _cal-loo-oo_. The Long-tailed Duck breeds in the Arctic regions of Europe, Asia, and North America, above the limits of forest growth, and, possibly, as far north as land exists. During summer, it frequents inland pools and lakes; odd pairs taking possession of the former, many pairs congregating on the latter. The birds arrive in the Arctic regions with the break-up of the ice, congregating in the pools amongst the floes. The nest is usually placed in some sheltered nook, amongst birch and willow scrub, in long grass, or on the drifted rubbish by the banks of the subsided rivers. It is little more than a hollow, lined with down. In this, during June or early July, from seven to twelve buffish-green eggs are laid by the female. It is a most remarkable fact that the drake of this species assists the duck in bringing up the young, but not, so far as I can learn, in incubating the eggs. During the whole breeding season this Duck is remarkably tame, loth to take wing, and swimming out into the centre of the lake for safety, if threatened by danger. The winter migrations of this Duck are not very extended, the Mediterranean Basin, perhaps, marking the extreme southern limits. MERGANSERS.