He is considerably larger than the weasel, measuring upwards of fourteen inches, including the tail--which is about four inches long, the tip almost black. He is a bold hunter, and follows and destroys the hare, and other animals of equal size. It is said, even, that several together will venture to attack a man. They are caught in America by traps, which, giving the animal a sudden blow, kill it without injuring the skin. The winter coat of the ermine is produced by the whitening of the fur, and not, as was once supposed, by the substitution of white for dark hairs. Probably one cause of this change of hue may be that the energies of the creature concentrate themselves on the vital organs, to enable it to resist the extreme low temperature of the icy regions it inhabits, and cannot thus spare a sufficient amount of blood for the formation of the colouring matter which tinges the hair. Human beings as well as animals become weaker as they increase in age; and it has been observed that their hair also loses its colour, in consequence of such energies as they possess being required to assist the more important functions of nature. This corroborates the correctness of the former remark. The ermine, like other species of its genus, has the faculty of ejecting a fluid of a strong musky odour. It is abundant, not only in the barren grounds of the Hudson Bay territories, but is also found in Norway and Siberia. When the fur is used for robes, or similar purposes, the black tuft at the end of the tail is sewn on at regular distances to the skin, giving to the ermine fur the appearance we are all familiar with. THE PINE-MARTEN. The pine-marten, a species of weasel, obtains its name from being found amid pine-forests, and from its habit of climbing the trunks of pines in search of prey. It is a fierce and savage creature, choosing to live alone, away from the haunts of man. It is from eighteen to twenty inches in length--with a tail measuring about ten inches--and is covered with long bushy hair. Moving without difficulty among the branches, it seizes many an unfortunate bird in its deadly gripe before its victim can take to flight--robbing also the nest of the eggs within it. It is common in Europe, as well as in America; but in the cold regions of the Hudson Bay Company it is hunted for the sake of its skin, which is, when blanched during the winter's cold, scarcely inferior to that of the celebrated sable. When pursued and overtaken, it stands at bay, exhibiting its teeth, erecting its hair, arching its back, and hissing like a cat. It forms its burrows in the ground, the female producing, a litter of from four to seven. Like other animals of its tribe, it emits a peculiar musky smell. THE OTTER.