123 



showing the region into which the marked plaice have spread, 

 from the region occupied during the previous two months. 

 We see, then, that there are three directions of migration : 

 (1 ) The retrograde one back to the " area of Kberation " and the 



Fig. 14. General synojitic chart showing the migrations of marked plaice 

 during the months August-December. 



similar regions to North and South of the latter — this is very 

 evident in the months November and December, and it still 

 continues during the months January and February. The 

 plaice are seeking the shallow- water regions just off the 



