OlSf THE MIGRATIONS AND THE GROWTH OF PLAICE. 149 



ground which limit the bays may therefore be considered to 

 act as barriers to migration. 



Of the 52 plaice recovered, only two made conspicuous 

 migrations, and only seven may be said to have left the bays 

 where they were liberated. The two just mentioned were 

 liberated in Goswick Bay to the north of Holy Island on 

 June 26th. One found its way to St. Andrew's Bay, where it 

 was captured on November 5th, and the other was caught on 

 May 27th this year seven to eight miles east of May Island. 

 On the same day at 6.15 a.m. 14 other plaice were marked 

 and liberated at Goswick Bay, and these were all taken from 

 Skate Roads, south of Holy Island. Six were recovered, the 

 two just mentioned, two at Goswick Bay. and two at Skate 

 Roads. The latter are the only ones we have record of which 

 offer us a hint at the homing instinct. As will be evident, 

 however, the position is very equally divided — two remaining 

 where they were placed, two migrating to considerable 

 distances to the north, and two returning home, it must be 

 said, over or around an extensive area of rocky and rough 

 bottom. 



If note may be taken of the smaller migrations it may be 

 said that the majority inclined to go north, but we cannot 

 overlook the fact that a certain number found their way to 

 the south. And these results would lead us to suppose there* 

 fore that the attractions of the food supply lead to small 

 migrations of the immature fish, but there is no evidence to 

 prove that a definite migration of plaice occurs in the inshore 

 waters of Northumberland. It is to be presumed therefore 

 that the majority simply migrate outwards to the deeper water 

 as they become mature. 



A consideration of the two which migrated so far into 

 Scotch waters suggests in the first place that if such a migra- 

 tion is at all general it is not necessary for the immature 

 plaice to go up the Forth to get to the north side; and shows 

 in the second that it is only in the case of an approach to the 

 locality which was the scene of the Scotch experiments that 

 we get results strongly confirmatory of these. 



