160 How to obtain it. 



hood, and injures or destroys them also. In a well ordered 

 hatchery this work should be done daily, even though there be 

 but few eggs to pick. There will be more amongst some lots 

 than others, but all the boxes should be carefully gone through. 

 This fungoid growth on the dead eggs is usually known amongst 

 fish culturists as " byssus," in centra-distinction from " fungus " 

 (Saprolegnia), which attacks both living fish and living eggs. 



The "fungus" (Saprolegnia) will attack both living and dead 

 fish, but the " byssus " ( Leptomitus davatus : STONED only grows 

 on the dead. When it occurs amongst eggs, as it most assuredly 

 will if the white ones are not picked out, it grows rapidly and 

 sends out innumerable filaments, which soon surround the good 

 eggs within its reach and cause partial suffocation. Such an 

 occurrence should never be allowed to take place, and is easily 

 prevented by punctually removing the white eggs as soon as they 

 become, opaque. I have known " byssus " appear within twenty- 

 four hours, which shows the necessity for prompt action. Should 

 any of the surrounding eggs be taken within its grasp, they may 

 not die immediately as a result, but the embryos are weakened 

 and cannot be expected to make good fish. If white eggs, after 

 being picked, be placed in a glass of sea water they will become 

 clear again, and on being transferred to fresh water they again 

 resume their opaque appearance, and the experiment may be 

 several times repeated with the same eggs. 



Sometimes healthy ova die and become opaque owing to 

 being attacked by living enemies, which have got into the hatching 

 boxes. It is in fact, exceedingly difficult at times to keep these 

 out. They come in the shape of eggs deposited in the water, or 

 in other stages, when they are very minute, and they soon grow 

 bigger and cannot get out again. These will attack the ova and 

 puncture the shell, which then allows the water to enter, and the 

 precipitation of the albumen follows as a natural result. With 

 good filters, cleanliness, and everything working efficiently, the 

 loss from this cause ought to be very small indeed. 



The "fungus" (Saprolegnia), to which I have referred, some- 

 times attacks the eggs, and woe to them should this happen. It 

 ought never to be allowed to do so, however, as it will not readily 

 grow upon them of its own accord. They do not form one of its 



