most strikes one in observing it is a feature connected with its caudal vertebrae to be
mentioned hereafter.
The vertebrae are C. 7,1 D. 14, L. 5, S. 4, C. 20. The spinous processes of the last
five cervical and first dorsal vertebrae are only rudimentary, and the neural arches
are antero-posteriorly narrow. The spine of the second dorsal is only moderately
developed and directed upwards and backwards, but the spines behind it, as far as
the tenth vertebra, decrease in size, and are very much depressed and confined to the
posterior margin of the neural arch. The spinous processes of the remaining dorsal
vertebrae have an antero-posterior extension co-extensive with the breadth of the
neural arch, and all are directed forwards, and, with the exception of the first which
is thin and plate-like, they are transversely thick and low, with flattened summits.
The spines of the lumbar region preserve the same characters with the last mentioned.
A minute process occurs on the side of the neural arch of each of the
last five cervical and first and second dorsal vertebrae; it is placed nearer to the
spinous process than to the zygapophysis. In the fifth dorsal a minute hyperapophysis
makes its appearance and rapidly increases in size, attaining its maximum
in the last lumbar. The lateral neural processes of the cervical appear to be
serially homologous with these dorsal and lumbar hyperapophyses.
The transverse processes of the cervical vertebrae are short and rod-like, and
overlap, but without touching each other; their inferior lamellae are shorter and
more pointed. The transverse process of the sixth is long, its anterior portion being
stouter than the lamellae in front of it, and its hinder half projects downwards and
backwards below, but rather widely separated from the head of the first rib, and
is long and somewhat sickle-shaped. A small eminence makes its appearance
posteriorly on the summit of the short transverse process of the third dorsal vertebra.
On the fourth vertebra it is a prominent, forwardly projecting process, occupying
the middle of the lateral surface of the neural arch above, and remote from the
slight projection on the side of the vertebra at the union of the lamina and centrum
to which the tubercle of the rib is articulated. As it is traced backwards to the
eleventh dorsal vertebra it approaches more and more to the anterior zygapophysis,
till at last it is closely in contact with it and touches the hinder margin of the
posterior zygapophysis of the vertebra in front of it, thus meriting to be regarded
as a metapophysis. In all these vertebrae its base is parallel with the spinal axis.
In the twelfth dorsal a small process appears between the anterior and posterior
zygapophysis, slightly below the level of the process I have just decribed on the
eleventh dorsal, but on a line with the articular surface of the anterior zygapophysis,
but, unlike the previous process, it is directed backwards, yet so gradual is the
change in level that the two appear to be continuations of one and the same element.
On the thirteenth dorsal a similar process occurs, but it is slightly more posterior
in its position, being nearer the posterior than the anterior zygapophysis, and at a
relatively lower level, being on a line with the inferior, anterior margin of the latter
| Owing to an accident, the atlas and axis were lost in removing the skull for examination.
zygapophysis. In the fourteenth, it is nearly as far back as and below the posterior
zygapophysis, with the very feebly developed transverse process of that vertebra
below it. In the first lumbar, the same process has become, as it were, the upward
and backwardly projecting process of the little-developed transverse process of that
vertebra. In the second lumbar it is still more developed, and indicates a ' decided
tendency to separate from the transverse process, which, although far from being
strongly pronounced, is directed downwards and forwards. In the third lumbar the
transverse process is slightly more marked than in the preceding vertebra, but the
process in question is reduced to a mere trace on its posterior margin, and in the
following lumbar vertebrae, in which the transverse processes increase in size from
before backwards, with, however, only a rod-like antero-posterior expansion, all trace
of it is lost. It would thus appear, from the twelfth dorsal to the third lumbar, to be
entitled to be regarded as an anapophysial process, but its gradual transition from a
metapophysial to an anapophysial position is very suggestive. A true metapophysis
may be detected in the second lumbar, and the same process occurs more intensified
in the third and fourth, but is reduced in the fifth. A well-developed, posteriorly
bifurcate hypapophysis occurs on the third and fourth cervical, and a ridge-like
hypapophysis on the vertebrae behind them to the second dorsal. Two rather widely
separated hypapophysial processes occur on the thirteenth and fourteenth dorsal and
first and second lumbar vertebrae, the remaining lumbar vertebrae having a ventral
longitudinal ridge on their centra.
The dorsal spines of the four sacral vertebrae are united into a rather prominent
ridge with a thickened margin, but the spine of the fourth is rather deeply separated
from the others. All the sacral vertebrae are firmly united together, but only the first
and one-half of the second are applied to the ilium. The first vertebra developes
on the sides of the sacral crest what appears to be a trace of united zygapophysial
and hyperapophysial elements, and a well-developed, bifurcate hypapophysis on the
anterior margin of its centrum: the remainder of the sacral vertebrae being ventrally
ridged, the third and fourth developing a feeble transverse process. The spinous
processes of the first and second caudaJs are well developed and halbert-shaped, and
backwardly projecting, while only a trace of the process can be observed on the third
caudal, whereas it cannot be detected on the following vertebrae. The processes
which support the anterior zygapophyses of the first caudal are very long and twice
as much so as those of the second caudal. Both processes arise from the anterior
surface of the base of the spinous process, and the articular surfaces which they
carry on the inner aspect of their extremities are applied, as it were, to each side of the
hinder end of the spinous process in front, so sessile are the posterior zygapophyses.
On the second caudal there are no traces of these last-mentioned processes, but the
last remnant of a neural arch can be detected passing below the spinous process.
All the caudal vertebrae, from: the third inclusive, are distinguished by the presence
of two rod-like processes on the upper surface of their anterior and posterior ends,
with another process in close apposition to each externally; the superior processes
doubtless are probably serially homologous with the anterior and posterior zygapo-
T