The nest itself is more or less artistically constructed of twigs, stalks, straw-grass, leaves, and similar materials, always well and warmly lined with down. The brood consists of from eight to fourteen eggs, but by regularly abstracting them as they are laid, the female will sometimes produce double those numbers. The eggs are well-shaped, rather elongate, slightly shining, and of a delicate greenish brown, grey, or dirty olive-green colour. Only the female sits, and upon her the guardianship of the young brood almost entirely devolves. Such as are born in nests placed at a considerable height, must necessarily be brought by her to the surface of the ground, but we are not aware that any naturalist has witnessed such a proceeding. It is just possible that, like some Ducks and Geese, they may leap from the nest trusting to their fluttering wings and thick downy covering to come off scatheless. Were we to judge by the observations we have had opportunities of making relative to the breeding of the Red-breasted Merganser (_Mergus serrator_), we should say that the young brood at first comport themselves exactly like young Ducks; soon, however, their natural peculiarities and special endowments begin to show themselves, and after the lapse of about eight days, they adopt the habits of their race. When first hatched they live upon small crustaceans and larvæ, caught upon the surface of the water, but on the third day are able to dive, and from the eighth day are quite capable of fishing for themselves. They grow very rapidly, and soon become independent. According to Naumann the instinct for brooding is so strong in these birds, that if robbed of their eggs, they will take possession of the nest of a Duck, and after forcibly driving away its owner, will sit upon her eggs till they are hatched. [Illustration] THE SEA-FLIERS (_Longipennes_).