THE SEA-FISHERIES 295 



has probably happened to some extent. Some post-war 

 statistics show an increased stock on the ground ; but 

 there is also some evidence of natural fluctuations in the 

 fish population which may give rise to conflicting evidence, 

 and so obscure the results of protection. The matter 

 cannot yet be regarded as settled. 



The true fishes (Pisces) that are caught by the fishermen 

 and sold for food in our markets belong to two main divisions 

 — (1) the Elasmobranchs, such as skates, rays, and dogfish, 

 with a cartilaginous skeleton ; and (2) the Teleosts, including 

 all the ordinary bony fishes. For practical purposes, the 

 bony fishes may be divided into the " round " and the 

 " flat " fish. Round fish are those — such as cod, herring, 

 and salmon — where the body is more or less circular in 

 cross -section, while flat fish include the equally familiar 

 soles and plaice, with flattened upper and lower surfaces. 

 Amongst round fishes there are two groups of primary 

 importance, those related to the cod (Gadidse) and those 

 of the herring tribe (Clupeidae). The former include : — 



Hake — a southern fish, forming the greater part of the 

 catch off the south of Ireland, in the Bay of 

 Biscay, and southwards to Morocco. 



Haddock — a northern fish, forming nearly half the total 

 catch from the North Sea. 



Cod — a northern fish, very abundant north of the British 

 area, around the Faroes, Iceland, Norway, etc. 



Whiting — abundant in the North Sea, and generally 

 around our coast. 



Ling — a northern fish, abundant on the west of Ireland, 

 Scotland, and farther north. 



The cod is probably the most useful of fishes to man. 

 All parts of its body are of value. In addition to its prime 

 importance as a food, both fresh and salted, oil is extracted 

 from the Hver, the head, tongue, and sounds also form a 

 good article of food, the offal and bones are ground up into 

 manure said to be equal to guano, the roe is used as bait 



