CHAPTER XVIII 



THE POWAN, THE TOLL AN, THE VEND ACE, 

 AND THE GRATLING 



GENUS COREGONUS 



THE genus Coregonus is a well-defined one, distinguished 

 among others of the Salmon Family by the smallness of the 

 mouth, the weakness of dentition, and the smallness of the ova. 

 About forty species have been recognised, most of which are 

 lake dwellers, although a few species descend to the sea 

 like salmon. They are the white-fish, frost-fish, etc., of the 

 North American lakes, where they provide very profitable 

 fisheries ; and they are found all over the arctic and temperate 

 parts of Europe and Asia. Three species are found in the 

 United Kingdom. 



The Powan, or Gwyniad (Coregonus dupeoides) 



FINS. 



First Dorsal : 14 or 15 rays. 

 Second Dorsal : Rayless, adipose. 

 Anal : 13 to 16 rays. 



TEETH. 



Few, minute, and deciduous ; when 

 persistent in adults, only on the 

 tongue. 



The name " powan " is of Gaelic origin ; it is but another 

 form of that of pollan, a species of Coregonus from Ireland, 

 and signifies a fish of the /><?/, lake or pool. Gwyniad is a 

 Welsh word, equivalent to the title of white-fish bestowed 

 upon this genus collectively in North America. 



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