DISrARITT OF SALMON-GROWTH. 199 



stage of existence. After that, the growth of tlie 

 offspring of large-growing sahiion, is more rapid 

 than that of the produce of salmon of more dimi- 

 nutive race. The smolts of rivers which pro- 

 duce salmon weighing forty pounds, grow faster 

 in the grilse and salmon state, than the smolts of 

 rivers whose largest fish do not exceed twenty 

 pounds ; and faster still than the smolts of rivers, 

 the salmon of which do not average more than ten 

 pounds in weight each. I will suppose these 

 rivers running, at short distances, the one from 

 the other, into the same arm of the sea, as do the 

 Shin, the Oikel, and the Carsely, and that smolts 

 from each descend simultaneously, and take up 

 their quarters on the same feeding grounds. 

 Again, I will suppose them returning in the 

 grilse state, simultaneously to their respective 

 rivers. It will be then found that the grilse of the 

 Shin will be larger and much longer than the 

 grilse of the Oikel, and that the grilse of the 

 Oikel will be larger than the grilse of the Carsely. 

 The reason of this disparity is, the full-growm 

 fish of the Shin are much larger than those of the 

 Oikel, and the parent fish of the latter are some- 

 what larger than those of the Carsely. 



The growth of salmon at sea, and at sea only, 

 after having attained in fresh water the smolt size, 



o 4 



