124 THE SEA-TROUT 



in the sea over winter to return, some of them, as maiden spring fish in 

 the following year. In pursuing further the same line of inquiry, Mr. 

 Johnston held, and Mr. Calderwood confirmed the fact, that, not only 

 do the lingerers not all return as maiden fish in the year subsequent to 

 that autumn in which the grilse spawned, but many of them delay 

 their return actually for four or five years, a proportion only of the 

 original run of smolts returning each season as maiden salmon for the 

 first time. 



Whatever be the real import of this provision of nature — of its 

 practical advantages to man there can be no question — it seems to me 

 to suggest the possibility of at least a partially similar habit in the 

 sea-trout. To be more precise, I think that the habit manifests itself 

 at this whitling stage, and that now a first great division of the shoal 

 occurs. In other words I think that a proportion only of each shoal 

 of smolts returns as whitling in the year of descent, though for some 

 reason not definitely known, or at least not definitely known to me, the 

 proportion varies from year to year in an extraordinary degree. It is 

 common to hear it said in a district that when any particular year is a 

 poor whitling year the next year will in consequence be a poor sea-trout 

 year. In my experience no reasoning can be more fallacious, for no 

 account is taken of the numbers of whitling which may have remained 

 over winter in the sea. In illustration I may point to the phenomenally 

 dry season of igii when, at Loch Lomond, there was an exceptionally 

 poor run of whitling. Yet in the more normal season of 191 2 there 

 was a remarkably heavy run of sea-trout, and shoal after shoal of them, 

 fish of from i-^ lb. to 2^ lb. in weight, had all the appearance of the 

 missing whitling of 191 1 now returned to fresh water for the first time 

 as mature sea-trout. I shall at a later stage show that scale examination 

 throws some light upon this question of the divided run. 



As for my suggestion that the constituent members of the proportion 

 of the shoal which ascends remain together, I shall with great 



