Prof. Reid on the Vogmarus Islandicus. 465 
spinal or mterhzmal spines in the turbot (Rhombus maximus) and. 
in the genus Platessa, and probably in all of the Pleuronectide. 
The tendons of two small muscular bundles, which run parallel 
to each interspinous or interneural spine, are attached on each 
side to the bifurcated extremity of the fin-ray embracing the 
cartilaginous disc. Between these two muscles a thin aponeu- 
rotic prolongation is sent mwards from the spine. At the an- 
terior part of the body the interneural spines and the spinous 
processes of the vertebre are equal in number, but towards the 
posterior part of the body where the vertebree become consider- 
ably longer, more than one interneural spine is mterposed be- 
tween two spinous processes. The vertebre varied in length 
and in their other dimensions in different parts of the spinal 
column. The first and second—counting from before back- 
wards—were considerably shorter than those which immediately 
succeeded them. The longest were placed in the posterior part 
of the spimal column. ‘The following measurements point out 
the relative length, and some of the other dimensions of these 
vertebree :— 
Number. Lengthininches. Height. Breadth. 
1 a of Nearly the same as the height. 
2 2% 2% 
3 2 
2 2% 
5 2% 
58 30 
59 rE 
60 2s 
61 12 
86 1 26 a 
87 1 
92 8 
%  *F 
The transverse processes of the dorsal vertebre were directed 
* It is exceedingly improbable that this marked shortening of the bodies 
of the fifty-ninth and sixtieth vertebree is their natural conformation, as they 
were nearly anchylosed by portions of cartilage which took the place of the 
gelatinous-looking substance occupying these cavities in the other vertebra, 
and the cavities themselves were considerably diminished in depth. Va- 
lenciennes says that in the Trachypterus leiopterus the number of the ver- 
tebrze is ninety or ninety-one ‘qui ont cela de remarquable, qu’elles vont 
toujours en s’alongeant, et méme en s’amincissant, ce qui rend les premiéres 
plus hautes que longues ; vers le milieu elles commencent 4 devenir un peu 
plus longues que hautes, et la longueur de celles de l’extrémité postérieure 
surpasse cing ou six fois leur hauteur.” 
Amn. & Mag. N. Hist. Ser. 2. Vol. iii. 30 
