FISH CULTURE. 



931 



tilting and shaking it the milt can be brought in contact with the eggs. Formerly it was the 

 custom to half fill the pan with water, but now the eggs are mixed as dry as they can be, and 

 it is found that a far higher percentage are impregnated. The milt seems to drown in water 

 quickly. Only enough eggs should be taken to cover the bottom of the pan with a single 

 layer. If more eggs are to be had, more pans should be used, and as soon as all the fish 

 have been handled they should be returned to the water. 



It takes very little milt to impregnate a large number of eggs , but, in practice, we gen 

 erally take all the milt we can get out of the haul. It is sometimes our custom also to put 

 the male fish, whose milt has been exhausted, into a pond by themselves, to keep them from 

 running up into the race again and troubling the females. This is a very good plan, if you 

 have plenty of ponds and plenty of fish. If you have but a small number of males compared 

 with the number of females, put them back again into the pond, as they will probably have a 

 second and third renewal of milt. 



After stripping a female once she should be returned to the tub from which she was 

 taken, and should be stripped again after a short time during which other fish are being 

 handled. This is to get the last egg from her, and if it is not done a few will remain, and 

 she will go on the spawning beds to deposit them, as if she had a full supply. If she is 

 cleaned entirely she will not bother herself or her owner about the matter again that season. 

 The California mountain trout retain their eggs and milt with more determination than our 



DISCHARGING OVA. 



IN -DOOR HATCHING BOX. 



brook trout, and must be humored like a cow that will not give down her milk to any one 

 but the creature for which nature intended it. After the trout are handled they are returned 

 to different tubs according to their sizes, as this is the occasion that we take for sorting them, 

 and then they are returned to their proper ponds. 



Twenty to twenty-five minutes having now elapsed since the pan of eggs was set in the 

 trough, gently tip up the pan. If the eggs are loose and roll separately as you move it, they 

 are ready for subsequent operations; if not yet loose, let them remain a while longer. 



The semen of the male is full of spermaiazoa or animalcules. These will live for ten or 

 fifteen minutes in water; dry, they will live six hours. There is a hole for the reception of 

 these sperms in each egg. The egg always sinks into the water with this hole at the top. It 

 receives one of the animalcules only by this opening, which then closes. There seems to be 

 a special arrangement of Providence that the eggs shall agglutinate stick fast to each other 

 and to everything they touch so that they shall not float away until they are impregnated 

 and the trout has had time to cover them. In the eggs of other fish, such as bass and perch, 

 the same arrangement is seen; only they stick fast the moment they touch anything, and 

 stay there until hatched out, while the substance that fastens the eggs of the trout dissolves 

 as soon as the mother has had time to protect them 

 VOL. II. 51 



