Prof. Reid on the Vogmarus Islandicus. 4.69 
The scapular arch is very flexible, rather slender, composed of 
a fibrous-looking tissue, is united to the skull at one point only 
—to the mastoid bone,—and is continuous throughout its whole 
length, so that it presents no traces of division into separate por- 
tions: About 23 inches from the lower edge of the body, the 
scapular arch bifurcates, and the two branches diverge and pro- 
ceed to the lower edge of the body, and are 2 inches apart at 
their termination. The anterior of these two branches is the 
stronger, and the pectoral fin is attached to it, a little below the 
bifurcation. 
Muscular System.—The muscular bundles of the trunk are 
enveloped in several strong fibrous sheaths, formed by prolonga- 
tions inwards of the fibrous part of the chorion or true skin, at- 
tached to the spinal column and to the strong lamine prolonged 
upwards and downwards along the processes of the spinal column. 
The muscles of the two sides of the body nearly throughout its 
whole height, are separated by a very strong fibrous partition 
extending upwards from the upper part of the bodies of the ver- 
tebree along the whole length of the spimous processes, and enve- 
loping that part of the lower extremities of the interspinous or 
Interneural spines interposed between these processes; and ex- 
tending downwards from the lower part of the bodies of the ver- 
tebree along the transverse processes and inferior spinous pro- 
cesses as far as they go, and thence continued onwards to the 
warty-looking cartilaginous tubercles arranged along the lower 
edge of the body. In the region of the abdomen this partition 
divides itself into two parts, forming the fibrous lining of the 
inner surface of the abdominal walls. Three strong aponeurotic 
septa are sent inwards from the inner surface of the skin to that 
part of this central partition placed above the spinal column, 
and two to that part below it, throughout a great part of its 
length. Another septum is sent inwards from the skin along 
the lateral line of the body to the spinal column, which is at- 
tached along the roots of the transverse processes in the abdo- 
minal vertebre, and to the central ridge on the bodies of the 
caudal vertebree. There are thus three strong sheaths containing 
muscular bundles placed between the bodies of all the dorsal and 
the greater part of the caudal vertebra and the upper extremities 
of their superior spinous processes, and two similar sheaths be- 
tween the bodies of a great part of the caudal vertebre and the 
lower extremities of their inferior spinous processes. The space 
between the uppermost of these sheaths and the superior margin 
of the body contains the muscular bundles which move the dorsal 
fin rays, and the space between the lowermost of these sheaths 
and the inferior margin of the body contains a thin layer of 
muscular fibres which is attached to the central partition, to 
