8 Mr. Carlisle’s Lecture on the Arrangement 
with those of the vertebral series, the apex of which is pre- 
sented towards the head. They are attached internally to the 
transverse and inferior spinous processes of the vertebras:. 
The ribs are placed in the line of the centre partition, and lie 
between the flakes. This series arises from a bone which 
borders the opening for the gills, and the pectoral fin, with 
its scapula and muscles, is situated between its foremost 
flakes. Wherever this series encloses the viscera, its flakes 
are shallow, and their thickness internally is not much less 
than at their external superficies. 
Lastly, the flakes of the ventral series ( ii ) form acute 
angles with the abdominal flakes, the points of which incline 
to the tail. It is attached anteriorly to the os hyoides, and the 
bones of the lower jaw. In its course it is bounded above by 
the abdominal series, and below by a membranous septum , 
within which the inferior single fins arise. The flakes, that 
cover the viscera, are shallow ; and they lie more oblique as 
they approach the tail. Both this, and the last described 
series, have their muscular fibres arranged according to the 
length and figure of the fish. 
Three large superficial nerves (kk) passing longitudinally 
from the head to the tail, in the course of the membranous 
partitions, give off fibrils at right angles, which bend inwards 
between each of the muscular flakes. A larger set of nerves 
are sent from the medulla spinalis , one between each flake, 
the branches of which seem to enter without ramifying there. 
Another small nerve passing from the head, and running 
deep-seated, and close to the dorsal spines, crosses and unites 
with each of the spinal fibrils, and at the junction a remark- 
able body appears : it is a loose transparent vesicle, about the 
