Genus Hystrix. (Linn.)
The Porcupines. of the old continent are distinguished by a very convex line of profile, the bones of the nose being much developed. The molar teeth are more elevated above the level of the jaw, and less irregular in their outline, and in the lines of enamel upon their crowns, than those of other genera of this Family. The feet are armed with large nails; the front ones have but four toes each, the presence of a fifth being indicated only by a nail: on the hind feet are five toes. The tail is short, with no prehensile power, clothed with quills open at the end, and, as it were, cut off.
The Common Porcupine (Hystrix cristata, Linn.) is found in Italy, and the North of Africa; but its introduction from the latter country to the former is mentioned by Agricola as having occurred in his time. It is one of the largest of the Rodentia, measuring nearly two feet in length, and some of its longest spines exceed a foot. It is of a dusky black hue, with a whitish band on the neck. On the head is a crest of long pale hair, capable of being erected at pleasure. The back, sides, and hinder parts, are armed with spines, which are very hard and sharp, about as thick as a goose-quill in the middle, furrowed through their length, and marked with broad alternate rings of black and white. They usually lie horizontally, but when the animal is excited (and he is very irritable) a set of muscles beneath the skin erects the spines, which then project stiffly, and present a formidable array which can-
