|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.
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
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.