8o6 



BULLETIN OF THE BUREAU OF FISHERIES. 



Cleaning the eggs. — It can not be avoided that a certain quantity of fatty 

 matter, always floating on the surface of the pond, will be drawn into the 

 collector along with the eggs, and foma a layer on top of the water. The 

 greater part of it can easily be removed with a stick passed horizontally along the 

 surface, but some will always be left and have to be taken up along with the eggs, 

 in the sort of shovel, covered with silk gauze, which is used for this purpose. 



The eggs and whatever is mixed with them are put into an oval bath or a 

 similar vessel, not too deep, and with just enough water to keep them floating. 

 Fresh water is then poured on, which causes the eggs to sink, while the fatty 

 matter remains at the surface. This is poured off, fresh water again added, 



Fig. 6. — Hatching apparatus. 



and when this process has been repeated two or three times, the eggs will be 

 clean. After this the vessel is filled with sea water, and, if necessary, a little 

 salt is added. The eggs will now float at the surface and may be taken out 

 and measured as usual. The collector has to be taken out and cleaned one or 

 two times a day.^ 



The hatching apparatus. — If cod eggs were scarce and difficult to obtain, 

 the main point would be to hatch the greatest possible per cent of the eggs. 

 As this is not the case, the question must be to hatch the greatest number of 

 fry for area of hatchery and hatching apparatus, and at the least possible 

 expense. It is from this point of view that the methods used at Flodevig have 

 been invented. The hatching apparatus shown in figure 6 is 7 feet 6 inches 



