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they are widely separated from each other. A ridge extends downward 
and posteriorly from the outer side of the zygapophysial process to the 
outer side of the convex exapophysis or parapophysis. I find no foramen 
inclosed between these processes, and can see no vestige of a cervical 
rib, such as is described in certain European pterodactyls. The posterior 
zygapophyses are concave and oblique, and above them, there is a more 
or less prominent process, a sort of “‘metapophysis.’’ They do not extend 
as far back as the ball, leaving a wide space between and back of them in 
which the floor of the neural canal is visible. The lamine are broad, thin, 
and roof-like, meeting in the middle and forming a very thin, neural 
spine. The length of the base of this spine varies not a little in the 
different vertebra, from twelve to sixteen millimeters. In only one 
vertebra is there a long spine, the one figured in Pl. XLIV, Fig. 17, which I 
take to be the seventh cervical. In the others, the free, thin border slopes 
slightly upward and forward, forming a rounded spine but a few milli- 
meters in height. 
Eighth cervical vertebra. Pl. XLIII, Fig. 8. The eighth vertebra, which, 
as already explained, is a real cervical and not a dorsal, was lying close to 
the first notarial vertebra, and near the presternal process of the sacrum. 
It has been so much compressed that all of its characters cannot be made 
out with clearness. A figure of it is given as it lay in the matrix. It 
differs greatly from the vertebra preceding it in the shortness of its 
centrum, the character of its spine, and in the presence of diapophy- 
ses. The ball is transversely widened, and has, at each extremity, 
a large, concave, articular exapophysis. The post-zygapophyses are 
situated much posteriorly to the ball, differing therein remarkably from 
those of the preceding vertebre. The spine above the zygapophyses is 
very short and thick; seen from behind, it is concave, and ends obtusely 
nearly over the zygapophyses. On each lateral expansion, near the upper | 
extremity, there is an oval, rounded, smooth surface, forming a sort of 
process corresponding to the ‘‘metapophyses”’ of the earlier vertebre. 
The front border of the spine is contave in outline, and is rounded. 
There is a rather slender and moderately long diapophysis, springing 
high up on the arch. In the specimen it has been compressed against 
the vertebra, but seems to end in an articular process. On the under 
side of the vertebra, near the mutilated diapophysis, there is a fragment 
of a rib, more slender than those of the notarium, which probably belongs 
with this vertebra. In the much confused anterior end of this vertebra, 
there is a small process on each side, evidently the exapophysis, which may 
also have served for the articulation of the head of the rib; if so, how- 
ever, the head must have been small. In the specimens of the P/eranodon 
vertebrz already described, this parapophysis seems either rudimentary or 
