3i8 BRITISH FISHERIES 



tions) that we postulate the existence of this 

 destruction in nature. Again, it has been found 

 impossible to rear large numbers of artificially 

 hatched fry up to the stage of the metamorphosis. 

 It would, of course, be quite wrong to say that 

 we shall never be able to avoid these two causes 

 of mortality in artificial conditions. If we could 

 do so, then sea-fish culture would have made an 

 enormous advance. Conversely, until we can do 

 so, the utility of the method must remain an open 

 question. 



Another line of argument, of much the same 

 logical order, which has frequently been advanced, 

 is at once ingenuous and plausible. In a specific 

 case l the cost of running a sea-fish hatchery for 

 one year was 600, and during that year some 

 300 millions of cod larvae were hatched and 

 liberated. The cost of 2000 larvae was therefore 

 id. Suppose that one larva in 2000 attains 

 maturity, or even grows to such an age as to be 

 worth is. There is, therefore, a very clear gain 

 in the process of hatching the fish. 



It is not difficult to discern the fallacious reason- 

 ing here. It has been pointed out that from this 

 assumed gain we must deduct the cost of catch- 

 ing the fish. This, however, is not the case, 

 because the process of putting more fry, and, to 

 a less extent, more marketable fish, in the sea 

 renders an impoverished fishing ground more pro- 



1 That of the Arendal (Norwegian) hatchery in 1895. 



