PROPAGATION OF TROUT IN AMERICA. 181 
entities and mind asserts its power over matter, that fecundity is 
proportionably lessened. The genus Salmo, therefore, as it includes 
the most intellectual families of all the oviparous tribes, seldom contains 
more than 25,000 eggs, and some trout not more than as many hundreds, 
yet the yield of spawn for one year only of a large pair of trout in good 
condition, would be worth, in a preserve of spring water, several 
thousand dollars. 
There are two general methods for propagating trout, whereas there 
appears to be but one for salmon, by reason of its migratory nature. It 
should therefore be propagated from impregnated roe, by artificial means. 
Cut streams and preserves may be stocked with small trout, or trout of 
any size required, by transporting them from streams stocked by nature, 
and that too without injuriously eliminating the serried ranks of speckled 
beauties, which would nourish and increase faster if the monsters of the 
pool, which require each a dozen fingerlings for breakfast, were re- 
moved for ever from the stream. 
Gentlemen who own preserves of trout should cull them occasionally 
with nets of large meshes and remove the large trout to a separate preserve 
or employ them to stock preserves with. Unless this course is pursued, 
the big fish will eat the small ones, and the large ones will become un- 
healthy and die without any apparent cause. This is frequently the 
case on parts of streams, where the trout are robbed by insurmountable 
dams of their spawning beds at the heads of the streams. Too much 
importance cannot be attached to the necessity for improving all dams 
so that trout may surmount them. Sawdust, tanbark and poisonous 
colouring materials, should be kept from trout streams, but the two first 
are disappearing so fast in the Eastern and Middle States as to create no 
serious apprehension. "They have done their worst, and robbed many 
streams of more value in trout than the lumber and leather was worth 
which caused the sacrifice. 
From our experience we should think that stocking living spring 
waters with trout propagated by nature would be the most economical 
course in this country. It is still a question, which has been the cause of 
many experiments in France, whether the young trout hatched by arti- 
ficial means from the ova are as healthy for the first year, and whether 
they will thrive as well as those propagated by nature in natural trout 
streams, and afterwards used to stock preserves with. 
Much depends upon the extent of a preserve of living spring water 
and its situation. If it is so extensive as to include several miles of 
stream above the pond or preserve, or only a fraction of a mile, well 
protected by a shore shaded with dense shrubbery, then the water may 
be led by pipes to lateral ponds, so as to keep the trout of different 
sizes separate, and artificial propagation may be resorted to with great 
success and profit. But a small pond, fed by only one spring, had best 
be stocked with trout by Mr. Aaron Vail, of Smithtown, Long Island. 
He takes all the responsibility of stocking ponds several hundred miles 
