IO2 DOMESTICATED TROUT. 



FURTHER DIRECTIONS FOR IMPREGNATING THE EGGS. 



5flx : foftoWifeg* ad optional suggestions may be of ser- 

 vice to the beginner in learning to impregnate trout 

 eggs. 



1. Use eggs that flow easily, and no others. It is true 

 that there will be some spavvners which, from an ex- 

 ceptional construction of organs, will not give their 

 spawn readily when ripe ; but in nineteen cases out of 

 twenty, when the eggs come hard they are immature ; 

 and the best rule to observe, at least in beginning, is to 

 take only the eggs which come easily. Avoid all others. 

 If the first half come easily and the balance less so, 

 take the first half and leave the rest. When you 

 perceive the eggs lying in rows under the skin, do not 

 try the fish at all. The ovaries are not open, and she 

 is certainly not ripe. 



2. Do not use too cold water. The eggs begin to 

 stick quicker, and remained stuck longer, in very cold 

 water than in warmer water. The zoosperms of the 

 milt also are less active and effective in very cold 

 water.* At all events, my experience has been that 

 very cold water is unfavorable to impregnation. In 

 October the water in the brooks will do very well, but 

 later, in November and December, it gets too cold, 

 and the necessary exposure to the cold air while 



* M. de Quatrefages says that the spermatozoa of trout milt 

 live the longest at a temperature between 41 and 48 Fahrenheit ; 

 but that when the temperature exceeds these limits, the increase 

 of the energy on the part of the animalcules compensates to a 

 certain extent for the shorter duration of their vitality. 



