91-2 ... 44-2 



11-5 ... 13-0 



25-1 ... 29-9 



31 



by the " Goldseeker " in the Firth of Forth, 1905-1910, the numbers 

 of plaice caught ^Der hour's trawhng will be found to be as follows : — 



Jan. -Mar. April-June. July-Sept. Oct.-Dec. 



15-1 ... 48-4 ... 66-8 ... 38-4 



These numbers are represented graphically in fig. 1, along with 

 a somewhat modified adaptation of the diagrams given by Fulton 

 in the same report, showing the catches of plaice made by trawlers 

 in the region immediately off the Forth. The diagram is based 

 principally on that given for small plaice, and a comparison of this 

 diagram with, those for medium and large plaice will indicate that 

 the summer diminution offshore is not due to absence of fishing, 

 and at the same time make it clear that the migrations at present 

 under consideration affect mainly the small plaice. 



From the same table in the above report we learn that the 

 average distribution of plaice each quarter during the same period 

 was: — 



Jan.-Mar. April-June. July-Sept. Oct.-Dec. 



Station 6 ... 63-7 ... 113-4 ... 230-1 ... 142-9 



2 ... 21-8 ... 113-6 



4 ... 16-2 ... 39-6 



7 ... 7-9 ... 35-3 



These figures are reproduced in diagrammatic form in fig. 2, 

 From these we have good reason for concluding that the immigra- 

 tion and the emigration take place via the northern station. Station 

 6. 



Similar conclusions with regard to the distribution of plaice on 

 the Northumberland coast will be derived from a consideration of 

 the lower part of fig. 3. This has been constructed from the infor- 

 mation m Table I. It will be observed that in this and the succeed- 

 ing figures the stations are indicated by a series of steps ; in the 

 case of plaice they are viewed from north to south, and in the case 

 of dabs from south to north. The wave of plaice which arrives 

 early at the northern station is continued southwards, reaching a 

 maximum in the southern bays about August as a rule. The 

 return migration doubtless contributes to the later maximum at 

 Skate Roads in the northern part of Northumberland. Blyth Bay 

 has been left out of this diagram for the reason stated in the previous 

 paper that it is influenced by the northern limit of a school to the 

 south of that now under consideration. Blyth Bay has an early 

 spring maximum, in April-May, and more than likely this is also 

 the case at Skate Roads, though we have no record of it, and with 

 this in mind an indication of it has been suggested in the diagram. 



