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EXPLANATION OF PLATE 14. 
Lyme Regis, presented to the Oxford Museum by Viscount 
Cole, enclosing within its ribs scales, and digested bones of 
Fishes, in the state of Coprolite. This coprolitic mass seems 
nearly to retain the form of the stomach of the animal, 
c, Coracoid bone, d. Scapula, e. Humerus, f, Radius, 
g. Ulna. (Scharf. Original.) 
Plate 14. V. 1. p. 191. 
Skeleton of the Trunk of a small Ichthyosaurus in the 
Fig. 5. Nearly flat articular surface of (probably) the third cer- 
vical vertebra of the same large Individual as Fig. 3. This surface of 
the bone has only a small cylindrical depression at its centre, instead 
of the deep, conical cup of the more flexible vertebrae, C. B. E. 
Near its upper margin is a wedge-shaped elevation (b) and near 
the inferior margin, a notch or furrow (a). These salient and re- 
entering portions articulated with corresponding depressions and 
projections on the surface of the adjacent vertebra, and acted as 
pivots, admitting a limited amount of lateral vibrations, and at the 
same time preventing any slip, or dislocation. 
Fig. 6. Concave surface of Fig. 5.; the wedge-shaped projection 
near its lower margin (a) must have articulated with a corre.spond- 
ing groove or depression on the front of the vertebra adjacent to it, 
like that at (Fig. 5. a.) As one surface only of these vertebrse had 
a conical cavity, the intervertebral substance must have formed a 
single cone, admitting in the neck but half the amount of motion, that 
the doable cones of intervertebral matter allowed to the dorsal and 
caudal vertebrae, (C. B. E.) where greater flexure was required, to 
effect progressive motion hy vibrations of the body and tail. 
These dispositions of the articulating facets of the cervical ver- 
tebra, acting in conjunction with the three sub-vertebral wedges 
before described, afford an example of peculiar provisions in the 
neck of these gigantic Reptiles, to combine a diminished amount of 
flexure in this part, with an increased support to their enormous 
heads. 
It is probable that every species of Ichthyosaurus had peculiar vari- 
ations in the details of the cervical vertebrae, and snbvertebral wedges, 
and that in each species these variations were modified by age. 
In the Gavial Mr. Mantell has recently observed that the first 
caudal vertebra is doubly convex, like the last cervical vertebra in 
Turtles. These peculiar contrivances give to the animals in which 
they occur increased flexibility of the Tail and Neck. 
