INIA GEOFFRENSIS AND PONTOPORIA BLAINVILLII. 97 
The remaining five cervical vertebree are compressed in the antero-posterior direction, 
but less so than in most Cetaceans. They do not present the peculiar depression and 
transverse extension characteristic of the cervical vertebrae of Platanista, but their 
bodies are nearly circular in outline, and the height of the neural canal bears a more 
considerable proportion to its breadth. The bodies increase but very slightly in 
thickness from before backwards. The arches are wide and low, their sides meeting 
above at very obtuse angle, and so narrow in the antero-posterior direction as to 
leave spaces between them about equal to their own breadth. They increase but very 
slightly in height from the third to the seventh, and possess but a mere rudiment of 
a spine, scarcely recognizable in the third, and but -2" in height in the seventh. The 
anterior and posterior articular facets of the arches are well developed in all, and have 
their usual relations. 
The transverse processes are, as usual, two on each side, upper and lower; the upper 
springs from the arch, the lower from the body of the vertebra. In the third vertebra 
these two are very near together, and approximate at their ends so as to enclose an 
oval foramen or canal -2" in its greatest diameter. On the left side this canal is com- 
pletely surrounded by bone; on the right side it is not quite completely inclosed. 
In Geluga similar rings are formed by the transverse processes of this vertebra, also in 
the Platanista described by Eschricht, though in the College specimen there is but a 
single broad imperforate transverse process. In the fourth vertebra the processes are wider 
apart, short, and obtuse, and of about equal length; a small elevation rises from the side 
of the body of the bone, midway between them. In the fifth vertebra they are still 
wider apart, ‘owing to the upper one, which is short and conical, rising higher on the 
side of the arch. The lower process is much larger, stouter, rounded at the end, and 
directed backwards. Although upwards of 4" long, it was evidently not fully deve- 
loped in this immature individual, being tipped with cartilage. The prominence of 
this process, contrasting with the almost rudimentary condition of all the others, is a 
marked characteristic of the cervical region. In Platanista and Beluga, as in most 
other Mammalia, it is the sixth vertebra which has the most largely developed inferior 
transverse process, in the former very remarkably so. It is worthy of note, however, 
that the Dugong (Halicore) agrees with Jnia in this respect, as well as in many other of 
the characters of the neck-vertebre. 
In the sixth vertebra, both upper and lower processes are small and conical. In the 
seventh vertebra the upper process is more developed; the lower one still exists, but 
in quite a rudimentary state ; behind it is a shallow excavation for the head of the first 
rib. The lamine of the arch of this vertebra are wider than in the others; its spine, 
as before said, is slightly higher; and the posterior surface of its body is transversely 
extended. 
The thirteen thoracic vertebree measure in length when placed in close contact 12-5". 
Their bodies increase at first rapidly, then more gradually in length—the first mea- 
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