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THE SALMON RIVERS OF SCOTLAND 



In seeking to elucidate the bearing which temperature has 

 upon the salmon's ascent of tributaries, it seems clear that 

 we are dealing with quite different conditions from those which 

 govern the ascent of salmon from the sea to fresh water. Once 

 the salmon has entered fresh water, the question of temperature 

 seems to play an important part. The steady ascent of the 

 main river is continued, though early fish certainly pause for 



