SMOLTS 7 
that artificial feeding can still further induce very 
marked differences. 
In all rearing ponds in Scotland, however, the 
smolt assumes the migratory dress at two years of 
age, although it commonly attains to the size of 
the natural or wild smolt before that period. This 
is strong presumptive evidence that the smolt 
naturally lives and feeds in our rivers for two years 
after hatching, and that it then is ready to go to 
the sea. Several attempts have been made to pre- 
vent the descent of smolts, so as to produce land- 
locked salmon. In most cases the attempts have 
failed, owing chiefly to the disappearance or death of 
the fish, as in the experiments of Messrs. Morgan and 
Pell in South Wales and of Dr. Murie in the ponds 
of the Zoological Gardens. At Howietoun greater 
success ultimately attended experiments made in 
this direction, for although many smolts jumped 
from the ponds and perished, so that the ponds had 
to be netted over to preserve the remainder, a fish 
was ultimately reared which was fertile and which 
spawned, and from which fry were reared.* The 
resulting specimen, however—the one fish which 
spawned—which was described as a grilse, was a 
very poor apology for a grilse as we properly under- 
stand this sprightly young salmon. The largest fish 
which is figured is ill-shaped, spotted, and with the 
parr marks still evident, and weighed only 14 Ib. 
It may resemble in some measure the land-locked 
salmon of the American lakes or of Sweden, but it is 
a poor thing to call a grilse, and forms in my opinion 
* Day, Trans. Linn. Soc., 2nd ser. “ Zoology,” vol. ii. part 15. 
