In early spring commences the season of his loves. His musky odour is then strongest, and quite perceptible in the neighbourhood of his haunt. He takes a wife, to whom he is for ever after faithful; and it is believed the connection continues to exist during life. After the "honeymoon" a burrow is made in the bank of a stream or pond; usually in some solitary and secure spot by the roots of a tree, and always in such a situation that the rising of the water cannot reach the nest which is constructed within. The entrance to this burrow is frequently under water, so that it is difficult to discover it. The nest within is a bed of moss or soft grasses. In this the female brings forth five or six "cubs," which she nourishes with great care, training them to her own habits. The male takes no part in their education; but during this period absents himself, and wanders about alone. In autumn the cubs are nearly full-grown, and able to "take care of themselves." The "old father" now joins the family party, and all together proceed to the erection of winter quarters. They forsake the "home of their nativity," and build a very different sort of a habitation. The favourite site for their new house, is a swamp not likely to freeze to the bottom, and if with a stream running through it, all the better. By the side of this stream, or often on a little islet in the midst, they construct a dome-shaped pile, hollow within, and very much like the house of the beaver. The materials used are grass and mud, the latter being obtained at the bottom of the swamp or stream. The entrance to this house is subterranean, and consists of one or more galleries debouching under the water. In situations where there is danger of inundation, the floor of the interior is raised higher, and frequently terraces are made to admit of a dry seat, in case the ground-floor should get flooded. Of course there is free egress and ingress at all times, to permit the animal to go after its food, which consists of plants that grow in the water close at hand. The house being completed, and the cold weather having set in, the whole family, parents and all, enter it, and remain there during the winter, going out only at intervals for necessary purposes. In spring they desert this habitation and never return to it. Of course they are warm enough during winter while thus housed, even in the very coldest weather. The heat of their own bodies would make them so, lying as they do, huddled together, and sometimes on top of one another, but the mud walls of their habitations are a foot or more in thickness, and neither frost nor rain can penetrate within. Now, a curious fact has been observed in connection with the houses of these creatures. It shows how nature has adapted them to the circumstances in which they may be placed. By philosophers it is termed "instinct"; but in our opinion it is the same sort of instinct which enables Mr Hobbs to pick a "Chubb" lock. It is this:--