122 
ORIGINAL ARTICLES. 
straighter, and more slender, than in the rest, and illustrate the na¬ 
ture of the transverse processes of the succeeding vertebrae, which are 
short and straight anchylosed ribs.”* Now if there be no evidence 
from young specimens that the tips of the transverse processes in the 
Serpent’s tail and the lumbar vertebrae of the Dugong contain se¬ 
parate centres of ossification, what is the objective reality expressed 
by calling them pleurapophyses P Besides all this, if, in its typical 
condition, the pleurapophysis be a bone striking directly outwards 
from a vertebra, what objective link is there between it and a rib in 
the ordinary acceptation of the term P 
The doctrine of Professor Owen, that there are two sets of trans¬ 
verse processes, diapophyses and parapophyses, has been very gene¬ 
rally accepted in this country, even by those who are far from agreeing 
with the main features of his theory of the costal arch. It has been 
taken into consideration that in the higher vertebrata the rib is 
usually connected with the vertebra at two places, that in certain 
instances, in birds and reptiles, the head of the rib is supported by a 
process as well as the tubercle, and that this process resembles the 
transverse process of the fish more nearly than does that which sup¬ 
ports the tubercle, in that it is unconnected with the neural arch; 
hence it and the transverse process of the fish have been called 
parapophyses, and the transverse processes of the higher vertebrata 
diapophyses. The transverse processes of fishes are thus presumed 
to correspond completely with the processes for the heads of ribs in 
other vertebrata, and to differ totally from the transverse processes 
in these. Also, in like manner, a complete correspondence must be 
maintained to exist between transverse processes of the higher ver¬ 
tebrata, and the superior row sometimes found in fishes. I hope, 
however, to prove, ere I conclude, that these are not the relations of 
these various processes. At present it may be noted that while the 
transverse processes of the tail in the Conger, Plaice, and other fishes 
have a very distinct correspondence to those in tails of mammals and 
reptiles, they are as truly in series with the ordinary piscine trans¬ 
verse processes in the trunk as are the inferior arches.f The undi¬ 
vided transverse processes of the trunk in the Conger are likewise in 
series with two rows of transverse processes on the vertebrae imme¬ 
diately behind the head, and the upper of these two rows has no 
apparent correspondence with the upper row which appears pos¬ 
teriorly. 
* Ibid. Yol. ii. p. 459, No. 2543. 
f I ought to notice that Professor Owen does not state that these processes are 
diapophyses. In describing the skeleton of Muraena Helena he states that “ the 
caudal transverse processes are due to a progressive bifurcation of the parapophyses •” 
and of the Plaice he says that “ the haemal arches are formed by special processes or 
divisions of the parapophyses, the external portions of which continue to project 
outwards, as independent transverse processes.” Descriptive Catalogue of OsteoL 
Series, Mus. Coll. Surg. Yol. i. pp. 14 and 48, Nos. 37 and 179. 
