PRINCIPAL FAMILIES OF FISH. 31 



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. 



Scojoelidce. 



Are deep sea fishes, among them is included Har- 

 podon nehereus, the " 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. 



Salmonidce. The Salmon family. 

 Are well known in Europe and North America ; it 

 includes the Salmon, Trout, Greyling and Smelt. 



