SPAWNING OF BLACK BASS 43 



'Critis cmd Nest-boxes. When the eggs in 

 the hatchery have all hatched in any one nest, 

 a crib or screen is usually placed around it to 

 confine the young fish until the time arrives to 

 transfer them to the fry-pond. The nests vary 

 much in size as well as in the number of eggs 

 which are deposited therein ; consequently it is 

 important that if a crib be used to surround 

 the fry it should be of large diameter (usually 

 2 ft. 6 inches). A crib is a circular frame- 

 work of heavy band-iron, with the sides covered 

 with cheese-cloth or thin muslin of good quality. 

 The top and bottom are left open. As it is im- 

 portant that the top of a crib be at least six 

 inches above the surface of the water, the depth 

 will determine its height, which should not be 

 less than four feet. Yet it is not a serious 

 matter if a crib be of less size than the nest, 

 because the male will keep the young outside 

 of it close to the crib ; when these outsiders begin 

 to rise, the attendants can gather them up with 

 a scap-net, but under such circumstances it is 

 impossible to prevent a few small bass from 

 escaping, and the work of saving the advanced 

 fry is very much increased. Those who have 



