320 BRITISH FISHERIES 



case of any sea -fish culture operations. One 

 instance of the apparently beneficial results of fish- 

 culture is made use of frequently, viz. the success 

 which attended the operations of the American Fish 

 Commission in introducing shad into the waters 

 of the Pacific coast of North America.^ Two 

 distinct results have been confused here : (i) the 

 effect of artificial hatching in increasing the 

 number of fish already present on a fishing 

 ground ; and (2) the result of the introduction 

 and acclimatisation of fish in an area where the 

 species dealt with did not previously exist. There 

 were no shad in the rivers of the American Pacific 

 seaboard, and what the U.S. Fish Commission 

 did was to introduce them there — an eminently 

 useful piece of public work, and highly credit- 

 able to a scientific organisation, but a piece of 

 work which does not bear the interpretation 

 frequently put on it. The Americans proved (i) 

 that it is possible to introduce fishes into an area 

 where suitable conditions exist — not an extremely 

 difficult thing to prove, by the way ; and (2) 

 that the larvs of fishes planted in a suitable 

 habitat may grow up to maturity — a result which 

 has an important bearing on the discussion of 

 fish-culture. It did not prove, however, that 

 it is possible, by artificial culture, to increase 

 the number of marketable fishes of a species 

 already present on the fishing grounds, to such 



1 Report Comm. U.S. Fish Commission Sot 1893, p. 72 (1895). 



