64 FISH CULTUEE 



begin spawning about the latter part of June. 

 Tbe period of incubation is about two weeks. 

 As soon as the young have absorbed their sacs 

 and are ready to swim up to the surface, they 

 are coaxed from their cavern to the water just 

 outside its entrance. Here they remain for a 

 day or two, being driven back daily into the 

 cave when the sun has gone down, or when en- 

 emies approach. Little by little, however, they 

 are led away, though kept closely herded, until 

 they appear on the surface of the water like a 

 big quivering black ball. In this manner they 

 work slowly back and forth over the pond. As 

 they move, the old fish swims slowly around 

 them, driving back into the mass any which may 

 stray. At this stage of their development the 

 fish-culturist steps in, and with one sweep of his 

 long-handled scoop-net gathers in the entire 

 school and transfers them to one of his small 

 ponds, where they can very quickly be taught 

 to eat ground liver, and, later, pieces of bread. 

 The fish grow quickly, and by the first of Sep- 

 tember are an inch or more long. 



Profit in Pond-culture of the Cat-fish. — ^Few 

 fishes offer greater possibilities than some of 



