70 American Fisheries Society 



it is still worth while to give each sort its proper location. 

 Thus it appears that small-mouth bass do better in rather 

 cool water and crappie are supposed to prefer theirs roily, 

 while sunfish thrive in the warmest locations, and the 

 catch-basin plan affords opportunity to humor these pref- 

 erences. 



It is probably quite impracticable to prevent occasional 

 overflow in some direction in case of heavy rain and on 

 such occasions small fish are likely to pass the screens 

 to the pond below or even through the entire series and 

 into the stream. The chance of this last may be lessened 

 by holding the large lower pond at such a level that it will 

 not easily overflow and the size of the pond makes it un- 

 likely that small fish will promptly find their way around 

 it and out. It is, therefore, to be expected that this pond 

 will collect some fish, which escape from the ponds above 

 and it seems worth while to stock it with a sort as little 

 voracious as available. With this in mind crappie have 

 been bred there for the last few years and have yielded 

 a crop of young although black bass and sunfish have 

 drifted in. It may be of interest to mention that under 

 the plan described above trout are constantly fed and 

 that aquatic plants appear dangerous rather than useful 

 in the trout ponds while the other sorts are never fed and 

 thrive about in proportion as vegetation is made to 



thrive. 



By way of summary attention is invited to four results 



of the catch-basin arrangement. 



1. Economy of water. 



2. Control of temperature. 



3. Collection of stray fish. 



4. Conservation of minute life. 





