DESTRUCTION OF IMMATURE FISH 293 



surface drift of the water of the North Sea, 1 and 

 it is very desirable that this should be repeated 

 with this particular question in view. Then, 

 though it is probably the case that floating fish 

 eggs are carried by this drift towards the Helgo- 

 land Bight, this is rather a deduction from Fulton's 

 experiments than an actually observed fact. 

 Hensen's work on pelagic fish eggs is the only 

 piece of experimental evidence of which I am 

 aware that is relevant to this question, and his 

 distribution maps 2 do not lend very decided sup- 

 port to the contention in question. Again, it is 

 probably the case that young flat fishes do migrate 

 from the small-fish " Eastern Grounds " towards 

 the deeper water fishing grounds of the North 

 Sea ; but here too direct experimental evidence is 

 wanting. 



So also with regard to the effects of shrimping 

 on shallow inshore waters, though in this case 

 the question is rather more complex. If we wish 

 to be assured that the cessation or diminution of 

 the capture of young fishes on any shrimping 

 ground is to be of material benefit to the fisheries, 

 it must be proved, for the particular area in question^ 

 that the young fish (say plaice) are only present 

 there during a particular stage in their life-history, 

 and that on the completion of this they migrate 



1 Fulton, Report^ Fishery Board for Scotland, 1894, pt. iii. p. 153. 



2 Hensen, Wissenschaftliche Meeresuntersuchungen, Kiel Kom- 

 mission, Bd. ii. (N.F.), Heft 2, 1897. 



