34 



A few large plaice annually visit the bay, usually towards the 

 end of the summer, and this is also the case on the coast of North- 

 umberland. The winter plaice apparently are practically altogether 

 the larger inshore sizes, but such also join conspicuously in the 

 movement which more particularly affects the smaller sizes. The 

 latter enter the bay in March, and evidently practically leave the 

 area entirely in November. 



Few dabs of over 12 inches as would be expected are evidenced, 

 and below that size the migration affects the 7-11 ins. dabs, and the 

 dabs below 7 inches in nearly equal degree. 



Returning to Northumberland, Tables III. and IV. and the 

 diagrams m fig. 5 may be considered. The tables are made up as 

 in Table I., but in this case the catches are arranged according to 

 size, and although the figures usually represent catches per hour's 

 trawhng this has not been strictly adhered to. The diagrams show 

 graphically the sizes during the months June (thin dotted Hne), 

 July (thick dotted hne), August (thin hne), and September (thick 

 hne). 



Plaice. — The tables and the chart bring out again the fact 

 that Vv'hile all sizes participate in the migrations the predominant 

 numbers are the small and the immature. There is a more or less 

 gradual dechne in numbers according to size, an expression of the 

 natural relationship of the numbers according to size, and which 

 would be still more perfect if our trawl net could catch more of the 

 smaller sizes. In Northumberland, so far as our few experiments 

 go, it cannot be said that there is any special size left predominantly 

 during the winter. If there is any evidence of preference it is of 

 plaice of from 8 to 12 inches. 



At the proximal end of the region, Skate Roads, the spring 

 arrivals consist almost entirely of small plaice. The autumn 

 maximum is brought about by the late arrival of large numbers of 

 plaice of 25-35 cms. at a period also when plamly the small plaice 

 are beginning to leave. There is a slight degree of evidence for a 

 still later appearance in the region of plaice of over 35 cms. to 45 cms. 

 And the evidence is clearer that at the period of their arrival the 

 fish below them in size have begun to leave the bay. The diagrams 

 for the southern bays of Northumberland illustrate the point 

 already demonstrated that they do not participate so largely in 

 the inshore movement. It is interesting to note that while the small 

 fish are arriving in July in the northern area, in the southern during 



