226 THE TROUT 



were receiving when they left the yearling ponds. 

 The plate of the mincing-machine will, however, re- 

 quire to be replaced by one with perforations fths 

 of an inch in diameter instead of ^ths, and the 

 amount of food thrown into the pond at each visit 

 must be gradually increased to keep pace with the 

 feeding capacity of the fish. 



It is only experience which will teach you exactly 

 how much food to give to a certain number of fish 

 of a certain age. The quantity varies greatly. The 

 temperature of the water, the state of the atmosphere, 

 the season of the year, the amount of natural food 

 these and other considerations have to be taken 

 into account. 



The different breeds of fish also feed differently. 

 The rainbow trout (Irideus), although a late spawner, 

 has a more voracious appetite and a quicker growth 

 than either the English brook trout (Farid) or the 

 Loch Leven trout (Levenensis) ; consequently a pond 

 full of the rainbow should be fed more generously 

 than the same number of their English or Scotch 

 contemporaries in an adjoining pond. 



' I think it safe to say,' says Livingston Stone, 

 ' that under favourable circumstances large trout of 

 any age will eat one-fiftieth of their weight per diem 

 in the summer, that one per cent, of their weight a 



