THE COD FAMILY AND THE SAND-EELS 255 



The egg is buoyant, and has a diameter of less than -^ in. 

 What the authors of Scandinavian Fishes mean by describing 

 the pollack as " the least voracious of its congeners " it would 

 be hard to say, for, with the possible exception of the coal- 

 fish, it is, in our seas at any rate, by far the most greedy, 

 pursuing the small fry with a boldness that is hardly equalled 

 in the blue shark. 



The Coal-fish, or Saithe (6^. virens), somewhat closely 

 resembles the pollack in outline, but the differences that reveal 

 themselves on closer comparison are considerable. In the 

 first place, the colour is distinct, being a deep bluish green, 

 with a pronounced blue quite absent from the other species. 

 Then the lower jaw protrudes less, and in quite young 

 examples it does not protrude at all. The chin of the full- 

 grown fish bears a small barbel, which further distinguishes 

 it from the pollack ; and in the young coal-fish this barbel is 

 proportionately much larger. It grows to a greater size than 

 the pollack, and is said to exceed 40 in. and 30 lb. Though 

 hardly an instance of what students of distribution know as 

 "vicarious species" — e.g. the llama of South America and 

 camel of Asia, or the rhea of South America and emu of 

 Australia — the coal-fish may in a measure be regarded as taking 

 the place of the pollack in some of the more northern waters 

 of Britain, the pollack, on the other hand, being far more 

 plentiful in the English Channel. The coal-fish is also said 

 to range to greater depths. 



In both its young and full-grown stage the coal-fish has an 

 extraordinary variety of local names ; but, as Day has given 

 a very representative selection of these, as has also "John 

 Bickerdyke " in his admirable Badminton volume on Sea- 

 fishing, it would serve no useful purpose to compile a list 

 here. As food the coal-fish is regarded as even less valuable 

 than the pollack. The writer can speak from experience only 

 of the latter, and the comparison is not flattering. 



In habits the two kinds appear somewhat similar, both 



