A VERY DIFFICULT QUESTION. 205 



its return homewards, shall be four ruonths. The 

 result will be, on a most probable average, that 

 the latter grilse will be double the size of the 

 former. So that ccEteris paribus, all things be- 

 sides being equal, the fish that remains longest at 

 sea, must, in ail cases be, though not the older, 

 the larger fish. 



The question will naturally here arise, why 

 should one fish remain longer on the feeding- 

 grounds than another?* It is a very difficult 

 question, one I do not think that can be very 

 satisfactorily answered. A fish may return from 

 the sea after a sojourn of one month, whilst 

 another may, in some very rare instance, re- 



* Mr. Young, in his pamphlet, says, — "We have also mark- 

 ed numbers of spawned salmon, both after their second and 

 third spawning, and have found, at all times, that the 

 length of their sojourn in the sea exactly corresponds with 

 the length of time from the smolt to the grilse, and from 

 the foul grilse to the salmon. The time from the smoltt; 

 descending to the rivers, until they return to the rivers as 

 grilses, is about eight weeks ; and from the time the spawned 

 grilses leave the rivers, until they return as salmon, about 

 eight weeks, and so on throughout all their after stages. 

 We allude here only to the great body of the fish, as there 

 may be numerous exceptions from this general rule, and 

 jiart of them we have seen, and heard of others, viz., some 

 of them retiring earlier than the time we have stated, and 

 others remaininir longer in the sea." 



