There is said to be another species of crab-eater in Cayenne, which differs from that we have described in the shape and proportions of its body, in the structure of its feet and claws, and in its tail being entirely covered with hair; and which besides seizes the crabs with its paws only. ANONYMOUS ANIMAL. This animal, which we shall call _anonymous_, until its real name shall become known, has some similarities to the hare, and others to the squirrel. We had the following account of it from Mr. Bruce: "On the south side of the lake anciently called _Palus Tritonides_, in Lybia, there is a very singular animal; it is from nine to ten inches in length; its ears are nearly half as long as its body, and proportionally broad, which is the case with no other quadruped, except the long-eared bat. Its muzzle resembles that of the fox, and yet it seems to approach nearer to the squirrel. It lives on the palm-trees, and feeds upon their fruit. It has short claws, and is a beautiful animal. Its colour is white, intermixed with a little grey and a bright yellow. Only the middle of the inside of the ears is naked, the other parts being garnished with large white hairs, and are covered with brown hair intermixed with yellow. The tip of the nose is black; the tail yellow, and black at the end; the tail is pretty long, but differently formed from that of the squirrel; and all its hair, as well on the body as the tail, is very soft." MADAGASCAR RAT. We have seen a figure of a small animal from Madagascar, which was taken from one alive in the possession of the Countess of Marsan. To me it seemed to approach nearer the species of the palm-squirrel than that of the rat; I was assured that it frequented the palm-trees; but I have not been able to procure further information concerning this animal. From its claws not projecting we may infer that it constitutes a species different from that of the rat, and approaches nearer to that of the palm-squirrel. The Dutch voyagers mention rats on the south-west coast of Madagascar, which they say live in the palm-trees, and eat the dates, and describe them to have long bodies, sharp muzzles, short legs, and long spotted tails; which characters so perfectly agree with those in the animal which we are now speaking of, that we are induced to consider them as the same species. The one which the Countess of Marsan had, lived several years; it was extremely brisk in its movements, and its cry was nearly similar to that of the squirrel, but weaker. Its manners were also like the squirrel, for it carried its food to its mouth with its fore-paws, and erected its tail; but it could never be tamed; it would bite desperately: it was fed with fruits and almonds; it only came out of its cage at night, and it felt no inconvenience from our winters, being kept in a chamber with a small fire. OF THE DEGENERATION OF ANIMALS.