Page:Encyclopædia Britannica, Ninth Edition, v. 15.djvu/408

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386 It is extensively distributed in the tropical parts of South and Central America, frequenting low swampy savannas, along the banks of rivers, and the depths of the humid forests, but is nowhere abundant. Its food consists mainly of termites, to obtain which it opens their nests with its powerful sharp anterior claws, and as the insects swarm to the damaged part of their dwelling, it draws them into its month by means of its long, flexible, rapidly-moving tongue covered with glutinous saliva. The Great Anteater is quite terres trial in its habits, being never known to climb trees, nor does it burrow underground like the Armadillos. Though generally an inoffensive animal, when attacked it can defend itself vigorously and effectively with its sabre-like anterior claws. The female bears but a single young at a birth. Tamandua. This genus closely resembles the last in anatomical structure, but the head is much less elongated, the fur is short and bristly, the tail, tapering, prehensile, with the under side through out and the whole of the terminal portion naked and scaly. The stomach is similar to that of Myrmccophaga, but with the muscular pyloric gizzard not quite so strongly developed. There is a distinct FIG. 3S. Tamandua AnU-atur (Tamandua tetradactyla). From Proc. Zool. S<c., 1871, pi. xliii. ileo-colic valve and short globular caecum. The fore foot has a very large claw on the third toe, moderate-sized claws on the second and fourth, a very minute one on the first, and none on the fifth, which is entirely concealed within the skin. The hind foot has five subequal claws. Vertebrae : C 7, D 17, L2, S 5, C37. There are very rudimentary clavicles. The Tamandua ( T. tciradactyla] is much smaller than the Great Anteater, and differs essentially from it in its habits, being mainly arboreal. It is an inhabitant of the dense primeval forests of South and Central America. As different individuals vary much in their coloration, it is possible that there may be more than one species. The usual colour is yellowish-white, with a broad black lateral band, covering nearly the whole of the side of the body. Cydolurus. The skull is much shorter even than in Tamandua, and is arched considerably in the longitudinal direction. It differs from that of the other members of the family mainly in the long canal for the posterior nares not being closed by bone below, as the greater part of the palatines and the pterygoids do not meet in the middle line. The mandible has a prominent, narrow, recurved coronoid and a well-developed angular process ; it is strongly de- curved in front. Vertebra : C 7, D 16, L 2, S 4, C 40. Kibs remark ably broad and flat. Clavicles well developed. Manus remarkably modified. The third digit is greatly developed at the expense of all the others ; it has a stout short metacarp al and but two phalanges, of which the most distal is large, compressed, pointed, and much curved, and bears a very strong hook-like claw. The second digit has the same number of phalanges, and bears a claw, but is very much more slender than the third. The fourth is represented only by the metacarpal, and one nailless phalanx, the first and fifth only by very rudimentary metacarpals. The pes is also completely modified into a climbing organ. The hallux is rudimentary, consisting of a metatarsal and one phalanx, concealed beneath the skin, but the other four toes are subequal and much curved, with long pointed compressed claws. The tuber calcanei is directed towards the plantar surface, and parallel with it and extending to about double its length is a greatly elongated sesamoid ossicle. These together support a prominent calcarine cushion to which the nails are opposed in climbing. Stomach pyriform, with muscular walls, but no distinct gizzard-like portion, as in the foregoing genera, The commencement of the colon provided with two small cteca, resembling those of many Birds, narrow at the base, and rather dilated at their terminal blind ends, and communicating with the general cavity by very minute apertures. Tail longer than the body, tapering, bare on the under surface, and very prehensile, fur soft and silky. This genus has also but one species certainly known, the Little or Two-toed Anteater (0. didactylus), an animal not larger than a [EDENTATA. Rat, of a general yellowish colour, and exclusively arboreal in its liabits. It is a native of the hottest parts of South and Central America. Family DASYPODID.E. The greater part of the skin strongly ossified. On the back and sides the union of numerous quadrate or polygonal scutes forms a hard shield, usually consisting of an anterior (scapular) and posterior (pelvic) solid portion (which overhang on each side the parts of the body they respectively cover, forming chambers into which the limbs are withdrawn), and a variable number of rings between, connected by soft flexible skin so as to allow of curvature of the body. The top of the head has also a similar shield (cephalic), and the tail is usually encased in bony rings or plates. The outer or exposed surfaces of the limbs are protected by irregular bony scutes, not united at their margins; but the skin of the inner surface of the limbs and under side of the body is soft and more or less clothed with hair. Hairs also in many species project through apertures between the bony scutes of the ba^k. The ossified dermal plates are everywhere covered by a layer of horny epidermis. Teeth numerous, simple, of persistent growth, and usually mono- phyodont, but in one genus ( Tatusia} a succession of teeth has been observed. Zygomatic arch of skull complete. Cervical vertebra? with extremely short, broad, and depressed bodies. The atlas free, but the second and third, and often several of the others, ankylosed together both by their bodies and arches. Lumbar vertebrfe with accessory zygomatic processes, and very large metapophyses, supporting the bony carapace. Clavicles well developed. A third trochanter on the femur. Tibia and fibula ankylosed at their distal extremities. Fore feet with strongly developed, curved claws, adapted for digging and scratching, three, four, or five in number. Hind feet plantigrade, with five toes, all provided with nails. Tongue long, pointed, and extensile, though to a less degree than in the Anteaters. Submaxillary glands largely developed. Stomach simple. Placenta discoidal, deciduate. The animals of this family are commonly called Armadillos, a word of Spanish origin, having reference to their armour-like covering. The existing species are all of small or moderate size. They are mostly, though not universally, nocturnal in their habits. They are omnivorous, feeding on roots, insects, worms, reptiles, and carrion. They are harmless and inoffensive creatures, offering no resistance when caught, their principal means of escape from their enemies being the extraordinary rapidity with which they can burrow in the ground, and the tenacity with which they retain their hold in their subterranean retreats. Notwithstanding the shortness of their limbs they can run with great rapidity. Most of the species are esteemed good eating by the natives of the countries in which they live. They are all inhabitants of the open plains or the forests of the tropical and temperate parts of South America, with the exception of one species (Tatusia pcba), which ranges as far north as Texas. Of the existing genera, Chlamydophorus stands apart from the rest in the formation of its external covering ; but in all other respects Tatusia is the most aberrant form, exhibiting a different type of structure of the fore feet, which in all the others shows modifications, though in very varying degrees, of the same type. Subfamily Chlamydophorinae. In most anatomical characters, especially the structure of the fore foot, this little group resembles the Dasypodinss, but it differs remarkably from all other known Armadillos, living or extinct, in the peculiar modification of the dermal armour. Chlamydophorus. Teeth ^- 9 , subcylindrical, somewhat com pressed, moderate in size, smaller at each end (especially in front) than at the middle of the series. Skull broad and rounded behind, pointed in front. Muzzle subcylindrical and depressed. A con spicuous rounded, rough prominence on the frontal bone, just before each orbit. Tympanic prolonged into a tubular auditory meatus, curving upwards round the base of the zygoma. Vertebrae : C 7, D 11, L 3, S 10, C 15. Upper part of head and trunk covered with four-sided horny plates (with very small thin ossifications beneath), forming a shield, free, and overhanging the sides of the trunk, and attached only along the middle line of the back. The plates are arranged in a series jof distinct transverse bands, about twenty in number between the occiput and the posterior truncated end, and not divided into solid thoracic and pelvic shields with movable bands between. The hinder end of the body is abruptly truncated and covered by a vertically-placed, strong, solid, bony shield, of an oval (transversely extended) form, covered by thin epidermic plates. This shield is firmly ankylosed by five bony processes to the hinder part of the pelvis. Through a notch in the middle of its lower border the tail passes out. The latter is rather short, cylindrical in its proximal half, and expanded and depressed or spatulate in its terminal portion, and covered with horny plates. The dorsal surfaces of the fore and hind feet are also covered with horny plates. The remainder of the limbs and under surface and sides of the body beneath the overlapping lateral parts of the dorsal shield are clothed with rather long, very soft silky hair. Eyes and ears very small,

and concealed by the hair. Extremities short. Feet large, each