1870.] HULKE—KIMMERIDGE PLESIOSAURIAN REMAINS. 613 
and the proximal halves of the right femur and humerus, with the 
smaller paddle-bones, already mentioned, of this Plesiosawrus. 
Mr. Mansel has recently seen these humeri and femora since 
their restoration; and he hag identified them as the limb-bones 
which he exhumed together with the spinal column which he sent 
me. Their general facies, the peculiar texture of their surface, and 
the correspondence of small pieces of the clay still adhering to them, 
confirm Mr. Mansel’s statement that these limb-bones did belong to 
the same individual. I may add that there is a close resemblance in 
these points between the paddle-bones and the large flat bones of 
the pelvic and breast-girdles. I have entered into these details be- 
cause, on account of the remarkable construction of the paddles, it is 
important that their identification with one another and with the 
spinal column should be as complete as possible. 
Spinal Column.—The spinal column is that of a long-necked Ple- 
stosaurus. All the early cervical vertebrae have been subjected to 
lateral pressure, which has flattened the sides of the centra, and re- 
duced their breadth, but increased their height. Throughout the 
spinal column the neurapophyses have been broken off from the 
centra, to which they were completely anchylosed ; and very few of 
them have been recovered. The eighty-six vertebree which have 
been preserved are distributed as follows. Twenty-seven bear a 
transyerse process low on the side of the centrum, and therefore 
belong to the front of the neck. Their combined lengths amount to 
nearly 5 feet; but the original length of this part of the neck was 
more than this, because several vertebrae behind the axis are cer- 
tainly wanting, and there is another gap between the 12th and 13th 
of the series. ‘Twenty-three have the transverse process replaced 
by a costal pit, higher on the side of the centrum, or they have a 
transverse process rising from the centrum into the root of the neu- 
rapophysis. These, then, are transitional vertebra between the front 
of the neck and the trunk, or between the dorsal and caudal seg- 
ments. Jam not acquainted with criteria by which the transitional 
centra of these regions can be certainly distinguished, the prethoracic 
and early thoracic from the lumbar ones. The larger ones I have 
assigned to the lumbar region, because their dimensions accord best 
with those of the early caudal centra. The united lengths of the 
transitional vertebree amount to nearly 4 feet. 
Nineteen have the transverse process borne wholly on the neura- 
pophysis, and are reckoned dorsal or mid-trunk vertebrae. Their 
united lengths give 3 feet 6 inches. 
Seventeen are caudals, all but the foremost bearing chevron-facets. 
Their combined length is 2 feet 6 inches. The united lengths of 
all the vertebree make about 15 feet; and taking into account the 
known large gaps in the neck, and the probability that other ver- 
tebre are also missing, the original length of the spinal column will 
probably be not overestimated at 17 feet. 
The atlas and axis are anchylosed. A shallow vertical groove on 
their side indicates their original separateness. The anterior arti- 
cular face of the atlas is a cup with a diameter of about 1-1 in., but 
