92 PRACTICAL TROUT CULTURE. 



infested egg may be said to resemble a minute ball 

 of cotton. Fig. 20, from the work of M. Coste, 

 gives an exact idea of its appearance. Should 



Fie. 90. 



this not be in time removed, it will become the 

 focus of contagion, the byssus will spread from it 

 as a center, and, attacking the living eggs in the 

 vicinity, soon involve them all in a common death. 

 The remedy for this is simple. As has been pre- 

 viously insisted on, remove daily all dead eggs, 

 and no nucleus of contagion can form. The bys- 

 sus is a proof of ignorance or neglect upon the 

 part of the person in charge. It is probable that 

 this is one of the greatest causes of loss in natural 

 incubation, as in that case no remedy can be 

 devised. 



We have met with severe loss from mice and 

 rats, but by covering the boxes these pests can be 

 readily kept off and a few well-poisoned candles 

 will soon destroy them. In fact, whenever poison 

 is to be used for the destruction of vermin, the 

 poisoned candles will be found the most safe and 

 convenient method of administration. We have 

 seen them offered for sale, but having found some 



