Page:Encyclopædia Britannica, Ninth Edition, v. 15.djvu/410

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388 MAMMALIA [EDENTATA. subcqual and alike, the first and fourth much shorter. Hind feet with five toes, all armed with strong, slightly-curved, conical, obtusely-pointed Hails. The third longest, then the second and fourth ; the first and fifth much shorter than the others. This genus differs from all the other Armadillos in having a pair of inguinal mammae, in addition to the usual pectoral pair, and in producing a large number (four to ten) of young at a birth, all the others having usually but one or two. The Peba Armadillo, T. septemcincta, is a well-known species, having an extensive range from Texas to Paraguay. It is replaced in the more southern regions of South America by a smaller species, with shorter tail, the Mulita (T. hybrida), so called from the resemblance of its head and ears to those of a mule. T. kapplcri is a large species or variety from Surinam. 1 Fossil remains of Dasypodidss have been found by Lund and others in the caves of Brazil in deposits of Pleistocene ago. Some are attributable to existing genera, but others are assigned to distinct modifications of the type called Euryodon, Chlamydo- t/icrium, Etitatus, &c. In the same region, but still more abundantly in the fluviatile deposits which cover the country in the neighbourhood of Buenos Ayres, are found the remains of one of the most remarkable forms of mammals yet discovered, the Glypto- dons, or Hoplophorida (fig. 39). They differ from the existing Dasypodidie in their large size, and in having the carapace composed of a solid piece (formed by the union of a multi tude of bony dermal scutes) without any movable rings, and in having also a ventral piece or plastron. The facial portion of the .skull is very short. A long process of the maxillary bone descends from the anterior part of the zygomatie arch. The ascending ramus of the mandible is remarkably high. The teeth are in all known species, all much alike, having two deep grooves or flutings on each side, so as to divide them into three nearly distinct lobes (fig. 40). The vertebral column is almost entirely ankylosed into a solid tube, but there is a complex joint FIG. 40. Teeth of Olypto- at the base of the neck, to allow the head d(m - Frora Owc!1 - being retracted within the carapace. The limbs are very strong, and the feet short and broad, resembling externally those of an elephant or tortoise. Many species of the family have been described and figured, especially by Burmeister (in the Annalcs del Musco piiblico de Buenos Aires), by whom five genera are recognized, which are thus characterized : T. Four toes only on the posterior feet. A. Four toes on the anterior feet, the pollex being absent. a. Cuirass thin but inflexible. 1. Jfoplophorus : //. cupliractus, H. ornatus, H. elcgans, H. pumilio. b. The cuirass stronger, with clefts between the scutes at the lower antero-lateral border, allowing of a certain amount of flexibility. 2. PanocMhus : P. tuberculatus, P. bullifcr. B. Both pollex and fifth digit of the manus absent. 3. Dosdimru-s : D. gigantcus. II. Five perfect toes on the posterior feet, and four on the anterior, the fifth digit of which is absent. A. Tail elongated, with the rings of the base smooth, and the, cuirassed apex cylindrical or tubular. 4. Glyptodon : G. clavipcs, G.rcticulatus. B. Tail short, the rings tubcrculated, the point round and short. 5. Schistopleurum : S. clongatum, S. asperum, S. livce. Family MAXIDJE. Covered externally (except the under surface of the body and inside of the limbs) with large imbricated horny scales, with scattered hairs growing in the intervals. No teeth. Tongue long, vermiform, and protractile. No accessory articular processes to the lumbar vertebra 1 , but the anterior zygapophyses largely de veloped and very concave, completely embracing the semicylindri- cal surfaces of the posterior zygapophyses. Limbs short, with fi complete digits on each foot. Scaphoid and lunar bone of carpus united. _Uterus bicornuate. Placenta diffused and non-deciduate. The species are mainly terrestrial and fossorial, though one is par tially arboreal. All belong to the Ethiopian and Oriental regions of the Old World. Manis. Skull somewhat of the form of an elongated cone, with the small end turned forwards ; very smooth and free from crests and ridges. No distinction between the orbits and temporal fossa-. The zygomatie arch usually incomplete, owing to the absence of the malar bone. No distinct lacrymal bone. Palate long and narrow. The pterygoids extend backwards as far as the tympanic?, but do not meet in the middle line below. Tympanic ankylosed to the surrounding bones, and more or less bullate, but not produced into a tubular auditory meatus. Eami of mandible very slender and straight, without any angle or coronoid process. From near the anterior extremity of the upper edge a sharp, conical, tooth-like process projects upwards and outwards. No clavicles. No third trochantcr to the femur. lingual phalanges bifid at their ter minations. Caudal vertebra} with very long strong transver.se processes and numerous chevron bones. Tongue long, vermiform, flattened towards the tip. The retractor or sterno-glossal muscles arise from the hinder extremity of the immensely prolonged ensi- form cartilage of the sternum. Stomach with thick, muscular walls and lining membrane, and with a special gland near the middle of the great curvature, consisting of a mass of complex secreting follicles, the ducts of which terminate in a common orifice. No cfficum. A gall-bladder. Head small, depressed,. narrow, pointed in front, with a very small mouth-opening. Eyes and pinna of ear very small. Body elongated, narrow. Tail more or less elongated, convex above, flat underneath. The whole of the upper surface of the head, the upper surface and sides of the body, the whole of the tail, and the outer sides of the extremities covered with large, overlapping, horny scales, with usually a few stiff hairs growing between and projecting beyond them. The sides and under surface of the head, the under surface of the, body, and the inner sides of the limbs without scales but with a rather scanty covering of hair. Limbs short. In walking the dorsal surface and outer sides of the phalanges of the two outer digits of the front feet alone rest on the ground, the points of the nails turning upwards and inwards. The third toe the longest, with a powerful compressed curved claw, the second and fourth with similar but smaller claws, that of the pollex often almost rudi mentary. Hind feet plantigrade, with hallux very short, and four other toes subequal, with moderate, curved, subcompressed nails. The animals of this genus, called Pangolins or Scaly Anteaters, are all of small or moderate size, terrestrial and burrowing, and feed mainly on termites. One small African species climbs trees. They can roll themselves up in a ball when in danger. Their peculiar elongated form, short limbs, long, gradually-tapering tail, and scaly covering give them on a superficial inspection more the appearance of reptiles than of mammals. The species are not numerous, but may be grouped into three sections. (1) Manis proper. Tail con siderably exceeding in length both head and body. Scales not covering the dorsal surface of the manus. On fore feet the first toe exceedingly small, but with a distinct short nail ; second, fourth, and fifth subequal, with moderate compressed claws ; third greatly exceeding the others, with a much larger falcate claw. Two species, both from West Africa : M. longicaudata (vertebra? : C 7, D 13, L 5, S 3, C 46), and M. tricufyms (vertebra : C 7, D 13, L 6, S3, C 44). (2) All the others have the scaly covering of the fore limbs extending to the claws, and the tail not exceeding the length of the head and body. On the fore feet the first and fifth toes are equal and very small, the second and fourth equal and longer, the third longest, but not so disproportionately so as in the other section. The tails of most of these are broad at the base and taper towards the extremity. They constitute the genus Pliolidotus of Gray, and include M. gigantecc, West Africa, the largest species of the group, of which the head and body measure 2 feet 6 inches, and the tail the same. Vertebrae : C 7, D 13, L 6, S 4, C 28. M. pentadadylci; M. aurita, and M. jaranica, all of the Oriental region. (3) One very distinct species, Jf. tcmminckii, from South and East Africa, with the tail nearly as broad as the body for the whole of its length, and rounded at the end, constitutes the genus Snmtsia of Gray. Family OKYCT?:IIOPODIJ .E. External surface scantily covered with bristle-like hairs. Teeth numerous, and of peculiar and complex structure, being traversed by a number of parallel vertical pulp-canals. Lumbar vertebra with no accessory zygapophyses. Femur with a third trochanter. Fore feet without pollex, but all the other digits well developed, with strong moderate-sized nails, suited to digging, the plantar surfaces of which rest on the ground in walking. Hind feet with five biibequal toes. Mouth elongated and tubular. Tongue subvermi- form. Placenta broadly zonular. Feed on animal substances. Ter restrial and fossorial in habits. Limited to the Ethiopian region.

Orycteropus. The total number of teeth appears to be from