228 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY 



habitat for large plaice. We made tliree hauls in Red 

 Wharf 'Bay during November of this year, with the object 

 of obtaining small plaice for the marking experiments, 

 and some attention was directed to the size of the plaice 

 captured. The statistics taken on this latter area are not- 

 comparable with those quoted for Luce Bay, as a net of 

 smaller mesh was employed in Red Wharf Bay, in order 

 to get a good catch of fish of from 8 to 11. inches in length 

 for the marking experiments. But it is no exaggeration 

 to say that in these three hauls not over ten plaice of over 

 15 inches in length were obtained, while the largest fish 

 caught was 16 inches long, and in two out of the three 

 hauls not one plaice of that size was obtained. It is 

 admitted generally that the principal effect of much 

 trawling on a ground is to diminish the average size of 

 the fishes inhabiting it. Now trawling is permitted to be 

 practised by sailing vessels, subject to the employment of 

 a mesh not less than 7 inches in periphery, in Red Wharf 

 Bay, while this method of fishing is prohibited uncon- 

 ditionally in Luce Bay, and it is this difference which, 

 in all probability, accounts for the fact that large plaice 

 are present in tolerable abundance in the latter area, 

 while they are very scarce in the former one. If trawling 

 in any form were prohibited effectively in Red Wharf 

 Bay — a prohibition which, however, we are very far from 

 advocating there can be little doubt that in the course 

 of a dozen years large plaice would be abundant there 

 also. 



The result of the single haul with a shrimp trawl, 

 which was made in Luce Bay on October 18th, goes very 

 far towards destroying the sharp distinction made 

 hitherto between " nursery grounds " and mature fish 

 grounds. Many hauls made on the iBnrbo Banks nursery 

 grounds, for instance, present a considerable resemblance 



