1 6 On Stocking. 



thirdly, to arrange the inflowing supply in such a 

 manner that the current cleanses the carbonic 

 acid from every egg the water being of course 

 raised to three or four inches depth so soon as the 

 eggs are well -on the hatch. If the troughs are 

 provided with trays or grilles, the eggs may be 

 spread on them and thus do away with the 

 necessity for lowering the water, but in any case 

 the supply of water should be equal to three 

 gallons per minute for each 10,000 eggs in any- 

 one trough, and this quantity may be safely 

 passed through any number of troughs not 

 exceeding five. But the most appropriate use 

 of ova as a means of stocking is by sowing it 

 down in redds. There are many lakes so remote 

 from railways and roads that practically it is im- 

 possible to convey a sufficient stocking of yearling 

 to them. In this case redds become a valuable 

 adjunct. There are few lakes that have not some 

 feeding stream suitable for naturally rearing fry- 

 here again a few redds, proportioned to the extent 

 of the rearing ground, should be used, thus ensur- 

 ing the best possible results at a minimum of 

 cost. 



The construction of redds and the selection of 

 suitable places will be found at page 54. 



COST OF OVA. The cost of Ova is composed of 

 two items one fixed namely, the cost of incuba- 



