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218 so tall that birds have built their nests among the branches."

The huts are built in the same general manner, projecting from the bank, or from an islet in the stream&#59; a spot being always selected where the water is at least three or four feet deep, to prevent the effects of severe frost. They are of a round form, with the summit, which rises to the height of several feet above the surface, domed over. The sides are enormously thick&#59; Hearne speaks of one which was "more than eight feet thick in the crown." A single entrance is made, which is covered with a projecting porch &#59; and this is invariably at some ‘considerable distance beneath the surface. “It is a great piece of policy," remarks the accurate observer already quoted, in these animals, to cover the outside of their houses every fall with fresh mud, and as late as possible in the autumn, even when the frost becomes pretty severe, as by this means it soon freezes as hard as a stone, and prevents their common enemy, the Wolverine, from disturbing them during the winter&#59; and as they are frequently seen to walk over their work, and sometimes to give a flap with their tail, particularly when plunging into the water, this has, without doubt, given rise to the vulgar opinion that they used their tails as a trowel, with which they plaster their houses&#59; whereas that flapping of the tail is no more than a custom which they always preserve, even when they become tame and domestic, and more. particularly so when they are startled."

The food of the Beaver consists in summer of the bark of the willow, birch, and poplar&#59; but as in the winter the ice confines them to their habi-