ARMADILLO (Dasypus, Linnaeus), a genus of the class Alfamniatia belonging to the order Edentata, and forming, with the allied genera Chlarayphorus and Orycteropus, a small but very distinct family intermediate between the Sloth.; and Ant-Eaters, and characterised by the possession of molar teeth only. The Sloths P1Raevves] have not only the ordinary molar teeth of common quadrupeds, but are likewise provided with large and powerful canines; though, as far as we know anything of their economy, they appear to be a purely herbivorous family, and to be even incapacitated by other details of their organisation for the capture or destruction of a living prey ; whilst the Ant-Eaters [ANT-EATER] are not only deprived of canine but likewise of molar teeth, consequently are without teeth of any description, and thus form the only family of the order Edentata that literally answers to the name and definition. Nor are these the only distinctions which subsist between the three families of edentulous mammals which wo have here indicated. Others are pointed out in the articles just referred to, and it will be sufficient to mention, in addition, that the Ant-Eaters differ from the other two families by the want of clavicles (a most important and influential element in the anatomical structure of all vertebrated animals), and the Armadillos, the more immediate subject of our present consideration, by the peculiar nature of their external covering. Instead of hair, the armadillos are covered with a specie]] of hard bony crust, forming three bucklers on the head, shoulders, and rump, respectively, the two latter being connected by a number of transverse moveable bands, very similar in form and appearance to the plate armour of the middle ages, from which indeed these animals have acquired the none of Armadillos—a name of Spanish origin, which has been adopted by English writers. These bucklers likewise hang down on each side, so as to form an effecturd protection to the belly, and partially to cover the legs and feet; whilst the pliancy produced by the moveable bands interposed between the bucklers of the rump and shoulders., and which are themselves connected by the soft pliant akin of the animal, permits the most varied and rapid motions. The bucklers themselves, as well as these counecting moveable bands, are composed of numerous small polygonal plates, placed contiguous to one another like the atones of a meanie pavement, but without any actual articulation, and they are incapable of separate motion. The whole thus forms a kind of Shelly buckler not unlike that of a lobster ; and though incapable of actual motion, yet the thinness of the shell, and, during life, the pliancy occasioned by the animal oil which penetrates it, allow it to yield to a certain degree, and thus to accommodate itself in some measure to the motions of the body. But the great and principal motions, as already observed, are eutirely due to the moveable transverse bands, interposed between the two principal bucklers of the body, and which vary in number according to the species, and even within certain limits according to the age, sex, or individuaL These are situated immediately above the loins, or in the region to which all the principal motions of the animal economy have beeu assigned ; the bucklers of the head and ahonlders are entirely disunited, and have none of these moveable bands interposed between ; but that of the head projects considerably backwards, and affords complete protection to the neck, which is indeed so short as to be bnrely distinguishable.
The throat, breast, belly, and thighs of the armadillo are naked, or covered with a thick granulated skin, thinly furnished with wart.' or tubercles, which give origin to a few coarse bristly hairs. The corn missures of the moveable hnnds on the loins are likewise provided with a number of long hairs; but with this exception the body is covered only by its peculiar shell. The tail is straight, rouud, thick, and pointed ' • it in adapted at the root to a notch or cavity in the posterior edge of the buckler of the croup, and, with the exception of one species, is universally covered with bony rings, formed, like the rings of the bucklers, of numerous small pieces connected together, but of a certain degree of motion, and thus admitting of conside rable flexibility in the tail itself. The head of the armadillos is flat and terminated by a pointed muzzle, which assists them, like the snout of the hog and mole, to turn up the earth in search of roots and worms. Their ears are erect and pointed, and their eyes very small. They have flat corpulent bodies ; and their legs are so dis proportionately thick and short that they barely serve to elevate the body above the surface of the ground. Their toes, also, of which there are either four or five on the anterior and invariably five on the posterior extremities, are remarkably short ; but they are furnished with extremely long powerful claws, slightly curved, and in every respect well adapted for digging or burrowing. So rapid indeed are the armadillos at this operation that they easily bury themselves to any depth beyond the reach of their pursuers. They can only be forced from their subterranean retreat by directing smoke or water into their burrows. Their strength and the tenacity of their hold are so great, that they have been known to leave their tails in the hands of the hunter rather than permit themselves to be drawn forth. Yet notwithstanding the shortness of their legs and the heavy corpulent make of their bodies, the armadillos run with a velocity which could not be anticipated from their general appearance. Most of the species will easily outstrip a man. Their ordinary burrows most commonly run for three or four feet at an angle of about 45 degrees to the plane of the horizon, then make a sudden bend, and terminate at the distance of eight or ten feet from the mouth. Here for the most part they conceal themselves during the daytime, for the greater number of the species are nocturnal, and never move abroad whilst the sun is above the horizon. This rule however admits of some exeeptions—a few species being found abroad at all times indifferently ; and it has been remarked that these are neither so swift nor so timid as the nocturnal species.