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The Dicynodontia

The pelvis and hind-limb of, A., Dromaeus; B., an ornithosceltd reptile, such as Iguanadon, or Hypsilophodon; and C., a Crocodile. The bird's limb is in its natural position, as is that of the Ornithoscelid, though the metatarsus of the latter may not, in nature, hare been so much raised. The Crocodile's limb is purposely represented in an unnatural position. In nature, the femur would be turned out nearly at right angles to the middle rertical plane of the body, and the metatarsus would be horizontal The Tetters are the same throughout. Il, illum; Is, ischium; Pb, pubis; a, anterior process, b posterior process, of the ilium; Tr, inner trochanter of the fomur; T, tibia; F, fibula; As, astragalus; Ca, calcaneum. I, II, III, IV., the digits
Fig. 78. - The pelvis and hind-limb of, A., Dromaeus; B., an ornithosceltd reptile, such as Iguanadon, or Hypsilophodon; and C., a Crocodile. The bird's limb is in its natural position, as is that of the Ornithoscelid, though the metatarsus of the latter may not, in nature, hare been so much raised. The Crocodile's limb is purposely represented in an unnatural position. In nature, the femur would be turned out nearly at right angles to the middle rertical plane of the body, and the metatarsus would be horizontal The Tetters are the same throughout. Il, illum; Is, ischium; Pb, pubis; a, anterior process, b posterior process, of the ilium; Tr, inner trochanter of the fomur; T, tibia; F, fibula; As, astragalus; Ca, calcaneum. I, II, III, IV., the digits.
Dicynodon and Oudenodon are lacertiform animals, sometimes of large size, with crocodilian vertebrae, four or five of which are anchylosed together to form a strong sacrum. The skull is massive and lacertilian in most of its characters; but the jaws are like those of the Chelonia, and were doubtless cased in a horny beak. Nevertheless, most of the species possess two great tusks, which grow from persistent pulps, lodged in a deep alveolus of either maxilla. The limbs appear to have been subequal and massive, with short and stout feet. The scapula and coracoid are simple and expanded, and there seems to have been no clavicle. The pelvis is very strong, with widely-expanded ilia, ischia, and pubes. The two latter meet in a median ventral symphysis, and the pubis and ischium of each side meet and obliterate the obturator foramen. The limb-bones are lacertilian in character.

Remains of these Reptiles have hitherto been found only in strata, which probably belong to the Triassic formation, in India and South Africa, and the Ural Mountains.