PRINCIPAL FAMILIES OF FISH. 
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uppermost ; and it is remarkable that when young 
their eyes are placed as in other fish, but become 
twisted round as they grow larger. The upper side 
of these fish is always dark, and the under side light 
coloured. 
The Sole, Turbot, Brill, and Flounder are English 
examples of this family, and some species are also 
found in India. 
Siluridce. 
This is one of the largest families of fish known, 
and includes no less than 114 genera, more than any 
other family ; they are inhabitants of the fresh waters 
of temperate and tropical regions, some of the species 
frequenting the sea also, and are numerously repre- 
sented in India. They are hardly known in Europe, 
one species only being found in the Eastern parts of 
Europe. They are without scales, and have fleshy 
tendrils or feelers attached to their mouths. Also 
frequently a gristly, or adipose fin on the back, placed 
behind the usual rayed dorsal fin. 
& 'copelidce. 
Are deep sea fishes, among them is included Har- 
podon nehereus, the u Bombay duck,” a well-known 
delicacy, when dried and smoked, in India. They 
have an adipose fin like the preceding family, but no 
barbels, and sometimes are covered with scales, en- 
tirely, or partially. 
Scdmonidcv. The Salmon family. 
Are well known in Europe and North America ; it 
includes the Salmon, Trout, Greyling and Smelt. 
