106 
THE CALIFORNIAN SALMON. 
of the reproduction of the salmon, in ponds where they 
are closely shut in, is then a fact acquired by science. It 
is shown here in a manner so general that it cannot be 
looked upon as an exception, and if nothing comes to inter- 
fere with this great experiment, the result must be yet 
more striking next season, when the fish have attained to 
a larger size. 
“ From this experiment, it appears also that the first 
spawning of the salmon takes place at eighteen months 
old, the same as that of the trout, and that the number 
of eggs of the first spawning is about two hundred. If 
these ova are less highly coloured than those of large fish 
caught in the open waters, this is probably from the flesh 
of the young salmon not having yet acquired the tint that 
it would have at a greater age. This takes away the last 
objection that has been made to the raising of salmon in 
close ponds, but to succeed in this industry, it is necessary 
to know how to choose conditions favorable for carrving 
it out.*^ 
In the experiment here described, it would have been 
much more satisfactory if the trout had not been present 
in the pond, and, singularly enough, no mention is made of 
their having been caught in the net with the salmon. I 
have tried to ascertain the final result of this interesting 
experiment, but have failed to find in the transactions of 
the Society, any further reference to it. All the authorities 
agree, however, that salmon detained in fresh water beyond 
the time of their migration to the sea, have their develop- 
ment checked and grow but slowly, and the possibility 
of obtaining matured ova from them before they go to the 
sea, is a curious scientific fact, rather than a discovery of 
much practical value. It might, however, be of some 
utility, where a small number of sea-going fish, were re- 
tained for the purpose of securing a further supply of ova, 
for their reproduction before being themselves liberated. 
