’ ARE, Wi ; 
Gea . 
* ‘ 
OF SOUTH CAROLINA. 27 
The neurapophyses are not connected with the centrum by the modes peculiar to either reptiles 
or cetacea, but are inserted in sockets on each side of the depression along which the medullary 
cord passes. 
The paddles are connected with the trunk by means more complicated than that found in cetacea, 
and in this structure they approach Reptilia. The ribs, which were bifurcated at top or proximal 
extremity, were placed along the whole of the vertebral column between the head and the pelvis, 
so that the animal had no neck. 
Plesiosaurus.—This was a contemporary of the preceding animal, and in many respects far 
more extraordinary. Cuvier has designated its structure as “altogether the most monstrous that 
has yet been found amid the ruins of a former world.” “'To the head of a lizard it united the 
teeth of crocodile; a neck of enormous length, resembling the body of a serpent; a trunk and tail 
having the proportions of an ordinary quadruped; the ribs of a chameleon and the paddles of a 
whale.” 
The cranium resembles that of the crocodile or alligator ; but is much smaller in proportion to 
the body. The occipital elements remain in a separate condition, and in this respect, as well as in 
the composite character of the lower jaw, it resembles the true Saurians. 
The teeth are placed in distinct sockets: they are slender, pointed, and a little arched and 
striated. The vertebra are somewhat shorter in anterio-posterior, than in the vertical or lateral 
diameter. The articular. surfaces are slightly concave, with a gentle convexity in the centre. The 
centrum is marked near its lowest surface by the costal pits, which are elliptical depressions, 
intended to receive the ends of the cost, and are placed a little below the neurapophyses. 
The most striking character of the genus is the extraordinary length of the neck, which is com- 
posed of from twenty to forty vertebra—nearly double the number found in any recent animal. 
Of this genus Prof. Owen has described, as occurring in England, sixteen species, and of the 
preceding ten. That so many species of animals so destructive and ferocious in their habits, should 
have been congregated together in so small a space, is a fact almost as extraordinary as their strange 
organization. ‘This order is connected with the next by a huge reptile called Pliosaurus. The 
flattened character of the vertebre of this fossil distinguishes it from the preceding—the length 
being one inch and a half, while the other diameter is five inches. The teeth are also peculiar— 
being somewhat trihedral at the summit. 
Crocodilia—The characters of recent Crocodilia have been described under the class. The fossil 
species, however, present modifications and characters unknown in recent forms. In living reptiles 
with concavo-convex articulating surfaces to the vertebra, the concave end is turned anteriorly and 
the convex end behind, but in the fossil congeners this order is often reversed, and some are even 
found with both articular surfaces concave or flat. Prof. Owen divides the order into two groups— 
the first containing those fossils with concavo-convex vertebrae, and the second including those 
with biconcave vertebre. To the first belongs Crocodilus Spenceri, which differs from recent 
erocodiles in the larger size of the temporal holes, the rapid tapering of the head forwards, and in 
the straight line joining the alveoli. In the second group we find Suchosaurus cultridens, which is 
characterised by teeth that are compressed laterally, and having trenchant edges, resembling the 
teeth of Megalosaurus, excepting that they are not, like them, serrated on the edges. They differ 
