6o MARKETABLE BRITISH MARINE FISHES chap. 



in the more northern parts of our seas ; the sole, pilchard, John 

 dory, conger, and various others are characteristic of the southern 

 coasts of Britain and Ireland. Soles are scarce north ol a line 

 drawn from St. Abb's Head to the northern extremity of Den- 

 mark. Halibut are scarce even in the northern part of the 

 North Sea, and only become plentiful as the Faroe Islands are 

 approached. Turbot and brill arc southern forms like the sole, 

 but extend somewhat further to the north. Speaking generally, 

 the majority of the cod family belong to the north, the hake 

 being the most southern, while of flat-fishes the forms most 

 similar to the plaice and halibut are northern, the rest southern. 

 On the south coasts families such as the mullets, breams, 

 and gurnards are abundant, which are scarce or absent in 

 the north. 



The various kinds differ also considerably in the depth of 

 water and distance from shore at which they live, and the depth 

 of water seems to be by far the more important of these two 

 conditions in separating the territories or ranges of different 

 fishes. Among the flat-fishes the species which lives nearest to 

 the land is the flounder, which is found chiefly in estuaries and 

 the lower parts of rivers, often ascending to fresh water, and only 

 going to sea to spawn, where it is not found beyond a depth of 

 thirty fathoms. Plaice is next in attachment to the shore, being 

 seldom taken on grounds more than forty fathoms deep, and most 

 abundant at from five fathoms to thirty ; it enters estuaries 

 also, but does not ascend so high as the flounder. The common 

 dab becomes rare beyond thirty-five fathoms, and like the plaice 

 is abundant in shallow water and in estuaries. The sole, like the 

 plaice, is often fairly abundant in shallow water, and enters 

 estuaries ; it is not found plentifully beyond forty fathoms. The 

 lemon dab has much the same limits as the sole, but is not so 

 common in shallow water near shore. The brill and turbot have 

 about the same limits as the sole, and are often taken in quite 

 shallow water, though seldom entering estuaries. The long rough 

 dab occurs at from twenty to fifty fathoms, and the megrim and 

 witch are deep-water species extending from twenty or thirty 

 fathoms to three hundred fathoms and seven hundred fathoms 

 respectiveh'. 



Among round fishes cod and haddock range from ten fathoms 

 to one hundred or one hundred and fifty, but adult whiting arc 



