This is a small and very beautifully ornamented Armadillo, which has three free central bands and a short tail, with large fore and aft shields. It rolls itself up on the slightest alarm, so that the great shoulder and croup shields meet, the head and tail fitting in exactly, in front, so as to close up the body very safely. The little animal, which is rarely more than fifteen inches long, and has a tail of a couple of inches in length, is found in Brazil, Paraguay, and Buenos Ayres, and its walking on the long, stout claws of the fore legs gives it a very curious and unsteady appearance.
It is an active, sprightly, light-footed little thing, according to Dr. Murie, and is constantly on the move, going here and there with much vivacity. Poising itself on tiptoe, it trots backwards and forwards as if on some urgent errand. In captivity the food was raw meat, boiled eggs, and bread-and-milk. In the forest land, where it dwells along with its fellow armoured creatures, it has the advantage of being able to curl itself up, and to present no tangible part of its body to the host of mischievous Monkeys of its locality. The other Armadillos, when retiring to their holes, are often set upon by their lively quadrumanous neighbours, and are dragged out by the tail with great gusto; but the little Tolypeutes curls himself up and laughs at the disappointed Monkeys, who can find nothing to pull at about him.
BALL ARMADILLO.
The shoulder shield comes down like a flap, far in front, and the croup extends behind in the same way, and they and the bands have large scales, which are very pretty in shape and ornament. The shields are very stout, and so is the skeleton within. The fore foot has three large clawed toes, on the tips of which the animal walks. The thumb of the fore extremity is to be seen in the skeleton, but is not always visible in the skin, and it is very small and high up; the index is long, and the claw also, and it is slightly bent, but sharp at the tip. The next claw is the largest and longest, and has a cutting edge at the back and outer part, and the point is sharp. The next digit is smaller. In the hind foot there are five toes, one being high up and rudimentary, and the second and third having broad, flat, curved, short nails, the third being the greatest. The fourth nail is smaller, and they are all placed more or less flatly on the ground.
The shell of this Armadillo is blackish-brown, and the skin between the central bands is bald and smooth. There are nine back teeth on each side in both jaws, and there are none in front. The muscles which enable this Armadillo to bring its tail and nose together and to form a ball shape, are not simply expansions of the common muscular tissue, which exists deeply in the skin in so many animals, but are special structures. The most important are in relation to the position of the head, neck, limbs, tail, and the shields and bands, when the body is about to be and while it is being rolled up; and these roller-up muscles are so arranged as to permit of the large liver and other internal organs not suffering pressure during their natural or temporary displacement. On the other hand, the unrollers act when the body and bones are in the rolled-up condition. The muscles of the back are very tendinous, and to a degree they unroll the animal, but this is also performed by muscles which are attached underneath the first movable band of armour, and to the front part of the spine of the blade bone; this will tend, when it contracts, to pull out the legs and protrude the fore part of the body, the centre being still rigid. Another drawer-back of the bladebone assists in this action, and it is inserted into the front or chest shield. The rolling up is done by the action of muscles which draw the nose down, so as to make the long head at right angles to the neck; then the fore-legs and bladebones are drawn in and up. At the same time, the muscles which pull down the tail act on the hind shield, and draw it down and forwards. The legs are pulled up, and then a great muscle, which is largely attached to the front and hind shields, and has a tendon-like expansion in the middle of its course beneath the movable bands, contracts and pulls front and stern together. The muscles of the loins, which in jumping animals bring the spine to a curve, do not act, and indeed are excessively small. The chief bend in the back is between the second and third lumbar vertebræ. (Murie.)
GENUS CHLAMYDOPHORUS.—THE PICHICIAGO.[80]
PICHICIAGO.
This is an Edentate animal, resembling the Armadillos more than any others, and is about six inches in length. It has a conical-shaped head, a large full chest, short clumsy powerful fore limbs, with four great nails rising gradually one above the other, the external shortest, and broadest; and the whole so arranged as to form a sharp-cutting instrument, rather scooped, and very convenient for progression under ground. The back and croup are broad and high, and the tail is small. The hind legs are weak and short, the feet being long and narrow, and there is a well-defined heel. The foot is arched, the toes are separate, and the nails are strong. The whole surface of the body is covered with fine silk-like hair, which covers over the limbs on to the palms. But the most striking peculiarity is the long-banded shell, which is loose as it were throughout, being attached to the back immediately above the spine by cellular tissue. It rests on two knobs on the frontal bones, and these are the great attachments of this important covering. There are twenty-four bands and no separate shields, and their consistence is somewhat more dense than leather of the same thickness. They are composed of scales or plates of geometrical form, and the bands are separated by skin. There is a notch in the last band for the tail, and the free inferior edges of the bands are everywhere fringed with silky hair. This elongated band structure is moved, to a certain extent, by two broad thin muscles, which are beneath it, on the back, and each of which divides, on approaching the shoulder, into two portions, one being attached to the bladebone, and the other to the occiput.