OBSERVED IN THE NORTH POLAR SEA. 521 
tongue is covered with small hook-shaped teeth, densely 
crowded. 
The bronddostegous membranes are thick, and the left 
one overlaps the right at their insertion into the root of the 
tongue ; they contain each nine small cylindrical rays. The 
gill-openings are large. The bronchial arches are furnished 
with double rows of club-shaped cartilaginous processes, 
rough with teeth. The posterior extremities of the arches 
are connected by soft membrane, the anterior ones by car- 
tilages. At both extremities there are slight plates covered 
with small teeth. 
Intestines. — The oesophagus, an inch long, is distin- 
guished from the stomach by its more delicate and whiter 
rugae. The stomach is a long sac, which makes a curve at 
its fundus. Its internal membrane forms nine or ten large 
longitudinal rugae, of a reddish colour. The pylorus is 
very distinct, being much contracted. The gut is nearly 
of equal diameter throughout, except immediately below 
the pylorus, where it is dilated. Into this dilated part the 
gall-duct opens on the one side, and a short, wide, obtuse 
caecum on the other. This solitary caecum is three-fourths 
of an inch long. The internal membrane of the gut is soft 
and villous, without regular rugae or plicae. There is no 
distinct rectum. The intestines make one convolution. The 
faeces have a honey-yellow colour. The liver is linguae- 
form, lies on the right side, with a small lobe on the left, 
and has a reddish-orange colour. There are two small 
spleens. The air-bladder is capacious, and communicates 
with the oesophagus. The kidneys are thickly spotted with 
dark-brown specks on a bluish-grey ground. The Hning 
of the abdomen is of a pearly colour, the roe of a pure 
white. 
Fins. — The dorsal fin, placed where the back slopes 
down to form the tail, and beginning opposite to the com. 
