go FISH-CULTURAL ASSOCIATION. 
ation concerning the numbers’and variety of our fishes, their 
food, manner of breeding, condition of life, migrations and 
stages of growth. The third degree of progress has been fish- 
culture, which may be called negative and positive; negative 
when obstructions to the increase’ of fish, such as improper ap- 
paratus and impassible dams are removed; positive when fishes 
are artificially bred, or when new species are introduced from 
distant countries. 
It may be fairly said that both forms of culture have already 
given considerable results. Of the success of negative culture, 
a familiar example is that of the smelt, which a few years ago 
had grown scanty in numbers and small in size on the Massa- 
chusetts coast, because the breeding fish were captured in the 
brooks, when crowded together on their spawning beds. The 
prohibition of this kind of fishing was followed within three 
years, by the restoration of the smelts to their former numbers 
and size. 
The best instance of positive culture is that of the California 
salmon in the Sacramento river, where Livingston Stone, by 
annually turning into the river 2,000,000 young fry, artificially 
hatched, increased the yearly catch from 5,o00,000 pounds to 
9,500,000 pounds. 
Wide experience in the hatching of shad and white-fish proves 
pretty clearly that a marked increase may be obtained, if the 
work be done ona scale large enough, and that an amount of 
work insufficient to produce a positive increase will, neverthe- 
less, check the decrease of these species. 
In a word, artificial breeding by greatly augmenting the pro- 
portion of eggs impregnated and by protecting them until 
hatched, presents a great advantage over the natural process, and 
gives us an available method of preserving many important fish- 
eries. But to produce results of commercial value, this waters 
culture must be practiced as universally and methodically as is 
agriculture. 
It is not the custom of Americans to stop half way in a profit- 
able enterprise. Therefore I do not doubt that in the next gen- 
eration some of our chief fisheries will be maintained by an 
established system of artificial culture. 
