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they happen to grow, so we fish the streams for whatever they 

 happen to contain ; and as it clears its Httle farm around its 

 burrow, so we make our Httle fish ponds, seine out the worthless 

 and destructive fishes, the snakes, frogs, and turtles, and throw 

 the better species back to increase for our benefit. In two 

 things our aquaculture is in advance of the agriculture of the 

 ants, — we have successfully introduced two or three foreign 

 species, and we have learned to take measures to maintain the 

 fish supply wherever it has suffered from the effects of overpop- 

 ulation. The first of these measures the ants have not thought 

 of, and the second they probably do not need, because their 

 numbers do not overrun their food supply. I believe it will 

 pay us to inquire whether we can hope to get beyond this ant 

 stage of aquaculture, and whether we may not learn to do at 

 least as much to increase and improve the product of the waters 

 of the country as the wild Indian did to cultivate the soil. 



At present, four things are done, in general : First, we 

 attempt to maintain or restore the relative numbers of our 

 valuable aquatic animals — fish especially — defending the popu- 

 lation of our waters against the evils growing out of civilized 

 settlement. This is like trying to restore the native growth of 

 trees and grasses to the surfaces deadened by travel and build- 

 ing, and by careless or unskillful usuage. Second, we try to 

 increase the relative numbers of the most valuable of our native 

 aquatic animals above the limit fixed originally by nature. 

 This is as if we should collect and plant the nuts and acorns in 

 the woods, and gather and sow abroad the seeds of the most 

 valuable native grasses, in the hope that this artificial aid might 

 enable our favorites to surpass their rivals. Third, we have 

 aimed to introduce foreign with our native species in our 

 natural waters. This is too much like sowing quantities of 

 apple seeds and wheat and corn broadcast in the woods and on 

 the prairies in the hope that if we use seed enough the plants 

 we seek to introduce will crowd out the native vegetation. 

 And, finally, we do, on a small scale, partly imitate actual agri- 

 culture by clearing or forming little patches of water here and 

 there, and planting in them an exotic fish, protecting it from 

 the competition of the native species. Here we approach the 



