62 
ROOM XI. 
Nat. Hist. 
rally live in the seas of cold and temperate climates, 
and by their abundance are important as objects of 
commerce. Their flesh is white, readily separates into 
flakes, is of easy digestion and very palatable. They 
are divided into several genera, according to the num¬ 
ber of the fins. The true Cod ( Morrhua) has three 
dorsal fins and a small beard ; the Coal-Fish ( Merlan - 
gus) has the same fins, but no beard; while the Stock- 
Fish ( Merluccius ) has only two dorsal and one anal fin. 
The Ling ( Lota ) differs from the latter in having a 
beard, while the Torsk ( Brosmius ) has only a single 
long dorsal fin. 
The family of Flat-Fish (, Pleuronectidce ) are peculiar 
amongst all the vertebrated animals, from the two sides 
of the head being dissimilar, both eyes being placed on 
one side, which is always superior when the fish swims, 
and strongly coloured, whilst the other side is white. 
The body is vertically compressed, fringed above by a 
long dorsal, and below by an anal fin. They live con¬ 
stantly in shallow water, on the shores of most coun¬ 
tries, and furnish an agreeable and nutritious food. 
They are liable to varieties; sometimes both the upper 
and under side are dark-coloured, and at others both 
are pale rosy white. When both the sides are brown, 
the fins are interrupted over the forehead, and the eyes 
are placed one on each side of the head of the fish. 
These fish have been divided into several genera, ac¬ 
cording to the length of the dorsal and the distinct¬ 
ness of the pectoral fins. Some, as the Zebra Soles 
( Plagusia ), are entirely without pectoral fins, and have 
the anal, caudal, and dorsal united into one. 
The third family of this division are the Suckers 
(Cyclopteridce), so called from the pectoral fins being 
united together into a disk, by which they attach them¬ 
selves to marine bodies. Their skin is slimy and naked, 
or with hard grains imbedded in it. The pectoral 
fins are large. They live in shallow water, near coasts, 
and swim wdth great vivacity. 
The Remorae (Echeneisidce) form the last family of 
the 
