SMOLTS 9 
seemed to have been successfully obtained, all the 
eggs died before hatching, 
In the experiments above related the abundance 
of food was carefully seen to, and up to the smolt 
stage, as has been said, such artificial feeding will 
induce excessive growth. Yet in attempts to pro- 
duce grilse in fresh water the best result is a stunted, 
flabby-looking fish. But a few attempts have also 
been made to produce grilse in confinement in salt 
water ponds. We have already seen what became 
of the Stormontfield fish. A fish from the Usk, kept 
in the salt water tanks of the Brighton Aquarium, 
is reported to have lived for five years, and to have 
then attained to a weight of 8 lb. Some similar 
experiments have, I understand, been made at Ply- 
mouth in the laboratory of the Marine Biological 
Association. Other experiments have been made at 
the mouth of the river Spey, in a pond specially 
excavated for the purpose by direction of the Duke 
of Richmond and Gordon. Those last-mentioned 
experiments I have in a measure been able to follow: 
The pond was constructed of cement work sunk 
in the gravel of the sea beach, and was connected to 
the sea by means of a syphon. In the second week 
of September 1901 some twenty-five smolts nearly 
two and a half years old were first introduced. In 
the adjoining fresh water ponds they had been raised, 
and having been retained beyond their natural time 
of migration, had already assumed and then lost the 
silvery dress. They were put straight into pure 
sea water, where they ceased feeding at once, and 
where in a few days four died. Ona certain admix- 
