POND-CULTUEE OF BLACK BASS 17 



of a brood-pond. The drawing off of water en- 

 tirely from September until March, is desirable 

 because it encourages the growth of plankton, 

 an essential feature in successful bass-culture, 

 and also because it destroys the larvaB of the 

 dragon-fly, and of water-beetles, the water- 

 beetles themselves and the crayfish, all destruc- 

 tive although furnishing food for the fishes. 

 Finally, the periodical drawing off of water as- 

 sists in keeping algae in cheek, — one of the 

 greatest nuisances known to fish-culturists. 



Introduction of the Stock. — ^For some years 

 it was universally believed that mature 

 bass must, under all circumstances, be intro- 

 duced from their wild habitat into the hatchery 

 in the autumn, to insure their spawning the fol- 

 lowing spring. An impression prevailed that 

 the fish required time to accustom themselves 

 to their new environments, and to recover from 

 the excitement or terror of capture and trans- 

 portation. 



Those who entertained this view may have 

 acquired it from the knowledge that some- 

 times, after abortive efforts had been made to 

 express eggs from a ripe female, she was un- 



