In order to make these houses, they begin by digging a large hole in the ground, about nine or ten feet in depth. This they line with poles and sticks, making, in fact, a wall as of a house. A stout conical roof is then raised over the hole, and upon the roof earth is thickly strewn and beaten down, just as has been mentioned when treating of the ice-house. The only access to this strange house is by a circular aperture in the centre of the conical roof, serving at once the purpose of a door, a chimney, and a window. A notched pole answers as a ladder, a low wooden dais placed against the wall serves as a bed or a chair, for there is no other, and a few stones placed together act as a fireplace. * * * * * IN looking at both these subterranean dwellings, I could not but be reminded of a very common insect which has a double dwelling, one moiety being aboveground, and the other moiety below it. This is the common Wood-ant (_Formica rufa_), whose large, leafy hills are so plentiful in some of our woods. On account of its size, this species is sometimes called the Horse-ant. At first sight the nest looks something like a small haycock, made entirely of chopped grass. When examined more nearly, it will be found to consist mostly of grass-stems, little bits of stick, and leaves. Those of the fir are in great request, for when they are dry they are very light, and their form enables the Ant to interweave them with each other, so as to form the necessary tunnels and galleries which line the interior of the nest. The materials seem most unpromising, but they are used with wonderful skill, such as no human fingers could equal. After a little while a number of entrances into the nest are visible. They are almost invariably sheltered by projecting leaves, which act as porches, so that when the nest is viewed from above, they are almost entirely hidden. Each of these openings runs into one of the main galleries of the nest, and from thence issues a perfect labyrinth of passages. This, however, is only half the nest, for the galleries and tunnels extend far beneath the surface of the earth, and have sundry enlarged portions or chambers wherein the immature pupæ may lie during their period of helplessness. Owing to the very loose structure of the upper nest, and the tendency of the earth to fall into the galleries of the lower nest, it is very difficult to obtain a trustworthy view of the interior. Perhaps I may here be allowed to extract a passage from my “Insects at Home,” the description of the nest and its interior having been written almost on the spot:--