1865.] OF PHYSALUS ANTIQUORUM. 221 
roundish body without processes. This general alteration commences 
by the neural spine decreasing in length and breadth, and likewise 
by the transverse processes becoming very much shortened, at the 
same time broadened and with a direction pointing forwards. While 
also the neural spine diminishes, it is set more slantingly backwards, 
and the metapophyses (Owen), which in the anterior vertebra are 
in comparison insignificant in size, assume extravagant proportions, 
and ultimately in the posterior vertebrae are the largest of the two; 
they shift their position so as to reach the summit of the neural 
laminze, and towards the last actually take the place of the neural 
spine. 
The bodies of the first twelve caudal vertebree are rather increased 
in depth below, the transversely ovoid form in the lumbar being here 
more triangular or carinated ventrally. 
The special differences among the caudal vertebree are in the first 
to the fifteenth having parapophyses and facets for the attach- 
ment of the chevron bones. In the fourth the neural spine shortens 
very considerably ; the metapophyses are strong and point upwards ; 
the lower groove in the body is deepened, and there are four para- 
pophyses, the two posterior having articulating facets. From the 
seventh to the eleventh vertebre there is a wonderful decrease in the 
size of the neural spine and transverse processes, which latter are 
reduced to a mere ridge in the eleventh ; these last have all, never- 
theless, a perforation through them. In the twelfth, thirteenth, and 
fourteenth vertebree the neural spines diminish ‘to little better than 
mere prominences, the metapophysés being the larger of the two. 
The parapophyses (two from each body) are perforated laterally at 
the middle. The transverse processes are only indicated by a slight 
elevation of the bone, which is pierced by a small foramina in the 
twelfth and thirteenth; but in the fourteenth this is altered to a 
groove. The fifteenth, sixteenth, and seventeenth present only ovoid 
or compressed discoidal bodies, processes or prominences being want- 
ing; on their outer sides, however, there are scattered several large 
foramina. In the remaining vertebree, which include the eighteenth, 
nineteenth, twentieth, and twenty-first caudal, the minimum of size 
is reached. Their bodies are short, thick, and somewhat quadran- 
gular, with no processes, though in the last there is a slight promi- 
nence on its neural aspect. Besides a lateral depression and _per- 
foration, they have on the under surface a single central foramina ; 
this exists from the fifteenth vertebra on till the twenty-first, where 
there are two. 
