Haasr.— Notes on Mesoplodon floweri. 447 
Thoracic vertebra. 
The species under review possesses ten, of which the bodies are all 
flattened from top to bottom, and getting gradually of larger dimensions, 
the body of the first being 1:12 inches, and the tenth 4-90 inches postero- 
anteriorlength. The spinous process of the first is pointed, and stands 
slightly forward. That of the second stands nearly vertical, after which in 
the remaining eight vertebre it gradually slopes more and more backward, 
and becomes higher and broader. This process in the second and third has 
rather a rounded apex, after which it becomes more truncated in the rest. 
Height of spine of first thoracic verebra, 4:25 inches; tenth, 9 inches. 
The articulation for the head of the second rib is situated at the posterior 
end of the first vertebra, low at the base of the arch ; it rises gradually in 
the two next, so that in the third vertebra this articulation is placed some 
distance above that base—a position which it maintains in the fourth, fifth, 
and sixth, after which it disappears, the following ribs having only one 
articulation. The transverse process which springs from both sides of the 
arch is, in the three first vertebre, a rounded apophysis ; in the next four 
vetebre it gradually enlarges, becoming, like in Epiodon nove zealandia, 
laterally compressed, showing one strongly marked process pointing 
upwards and forwards, as well as a well-indicated and posteriorly-situated 
articulation for the tubercle of the ribs. 
A separation into two distinct processes takes place in the eighth, the 
forward or anterior process of the apophysis now appearing as the metapo- 
physis, and its lower or posterior process forming a lower transverse pro- 
cess, starting as a small rounded prominence from the anterior border of 
the upper portion of the body, and on which the articular surface for the 
eighth rib is situated, directed obliquely backwards. 
In the ninth vertebra this separation is still more accomplished, the 
metapophysis being well developed, and the transverse process, which 
springs now from near the centre of the body, although thicker and more 
rounded than those of the succeeding vertebre, takes already their usual 
form. It has an articular surface for the ninth rib on its posterior end, 
with the same direction as the preceding one. 
The tenth vetebra, which is the largest of the series, has a very large 
transverse process, depressed and broad, on the edge of which the tenth 
small rib obliquely articulates. This transverse process is the broadest 
and longest of the whole series of vertebre, those of the lumbar region 
beginning with the first, getting by degrees shorter and narrower. 
The transverse process of the ninth thoracic vertebra has a horizontal 
and somewhat backward direction ; that of the tenth stands straight, whilst 
the same process in the lumbar and the first series of the caudal vertebra 
have, beside, a slightly downward, also a forward direction. 
E 
