24 FISH CULTURE. 



and by far the larger number, do migrate at one 

 year, a considerable number do, nevertheless, remain 

 behind, and stay in the river for another twelvemonth, 

 migrating at the same period of the year as their 

 more precocious brethren. Some of them will often 

 remain even three years in the fresh water. Why 

 this apparent irregularity should take place no one 

 has yet been able to discover, nor has any rule or 

 law whereby such an apparent freak is guided or 

 accounted for yet been satisfactorily established. It 

 having been supposed by Mr. Buist, the experienced 

 superintendent of the Stormontfield experiments in 

 salmon breeding, that this might have happened in 

 consequence of some of the ova or milt being taken 

 from grilse or salmon after only one journey to the 

 sea, he took particular care in the fall of 1860 to 

 have the whole of the milt and ova taken from 

 full-grown salmon; but this made no difference, for 

 in May 1861, about the same proportion of young 

 fish left for the sea, and about the same proportion 

 also remained behind in the ponds as usual The 

 smolt having reached the sea remains there for a 

 period varying from two to four months, when it 

 again returns to the river in the form of a young 

 salmon or grilse, having increased in weight to a 

 wonderful degree, grilse varying from 21bs. to even 



