SCIENTIFIC WORK IN THE SEA-FISHERIES. 249 



fishes, their growth, and the changes at the different seasons, 

 together with the appearance of anadromous fishes like the 

 Salmon, at various stages, and would decide as to the present 

 position of the British sea-fisheries in the North Sea. 



Such a survey cannot be efficiently carried out by sub- 

 ordinates whilst the chief remains on land, since the experience 

 gained under varying conditions gradually takes a definite shape 

 after years of careful observation and inquiry at sea. Such 

 experience is not gained by examining boxes of fishes on shore, 

 by the tabulation of recorded observations, or the manipulation 

 of sheets of figures filled up by others on board the experimental 

 ships. 



Another point, again, in these investigations is the effect of 

 the operations of fishing-vessels in connection with variations in 

 the abundance and in the size of the food-fishes. Such is a 

 promising field for observation, but by no means international 

 in character. It would include, for example, the effect of the 

 work : — 



a. In temporarily diminishing the larger fishes, and render- 

 ing the smaller more conspicuous. 



b. In making the survivors more wary. 



c. In driving the shoals of pelagic forms from particular 

 grounds, or otherwise. 



d. In demonstrating the effective nature of sudden changes 

 in the method of capture — e.g. the substitution of Anemones for 

 Mussels, of Cuttle-fishes for Herrings, of Lobworms for Scallops, 

 and of the alternation of gill-nets with tempting bait of various 

 kinds. Few appreciate the revelations made by such a change 

 of method. 



Other important points that suggest themselves to the in- 

 vestigator are the special study of hard grounds unsuitable for 

 trawling, if any such exist in the North Sea. 



The food of fishes and the pelagic fauna and flora are less in 

 need of attention, since they already have been investigated 

 sufficiently for all practical purposes. 



Such are some of the problems that would have suggested 

 themselves for solution on facing this inquiry. 



It is difficult to ascertain precisely what the British investi- 

 gators expected to discover, but the task of ascertaining "whether 



