DIRECTOR S REPORT. 295 



parts of the North Sea. In this number will be found a paper by 

 Mr. Cunningham dealing with this material, as compared with the 

 specimens collected at Plymouth. The study of pigmentation in 

 fishes is the outcome of the interesting experiments instituted two 

 years ago, and still in progress — I refer to the cultivation of pigment 

 on the under side of flat-fishes by the action of reflected light. 



In my last Eeport I gave a sketch of the work in the North Sea 

 at present being carried on by Mr. Holt. Much valuable in- 

 formation has been collected as to the sizes at which the various 

 food-fishes spawn for the first time ; and it is found that just as the 

 fish of the North Sea are, as a rule, larger than those caught on 

 the south coast, so the spawning periods occur when the fish are of 

 larger size. If legislation as to trawling in the North Sea is to be 

 contemplated, and a restriction put upon fishermen as to the sizes 

 below which it is illegal to capture or sell fish — this legislation 

 being international in character, — then the only rational point of view 

 from which to regard the question is surely the biological one. If 

 we follow the example of a maritime power on the other side of the 

 North Sea, and make the restrictive sizes so small that the fish have 

 never had a chance to spawn before they are captured, then, it 

 appears to me, we do good only to a very limited extent. We do 

 not help in any way to maintain the upkeep of the breeding stock, 

 and therefore do not in the slightest degree touch the question of 

 increased food supply. We only aid the fisherman to some slight 

 extent by keeping very small fish out of the market. We make 

 him sell his small immature sole for a shilling instead of his minute 

 sole for a sixpence. We do not in any way prevent this improvident 

 person, who is, of course, working for a living against keen competi- 

 tion, from drawing upon his stock in trade until he has no more to 

 sell; and since the fisherman represents the manufacturer, so far as the 

 consumer is concerned, the process sooner or later works itself out 

 till the fisherman disappears, and the consumer finds that he can 

 no longer buy his sole. 



A very serious difficulty which presents itself in connection with 

 the North Sea trawling industry is, that to prevent the capture of 

 fish till after they have spawned once, would mean the temporary 

 elimination from the markets of a very considerable quantity of 

 certain species, and a corresponding reduction in the incomes of the 

 fishermen or fishing companies, who can already ill afford to submit 

 to such a process. 



Mr. Holt, in his ''Remedial Measures ^^ at the end of his paper on 

 The Destruction of Immature Fish in the North Sea, deals with 

 this important question, and I would call the attention of those 

 interested in the North Sea investigations to this section. 



