CHAPTER XVIII 
THE POWAN, THE POLLAN, THE OENDACE, 
AND THE GRAYLING 
Genus COREGONUS 
Tue 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 clupeoides) 
FIns. TEETH. 
First Dorsal: 14 or 15 rays. Few, minute, and deciduous ; when 
Second Dorsal: Rayless, adipose. persistent in adults, only on the 
Anal: 13 to 16 rays. 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 po/, 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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