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TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY 



following tables give the details of recapture and growth 

 of the fishes returned. The " analyses of sizes of fish 

 recaught " give the numbers of plaice of each size group 

 (every quarter of an inch) marked and liberated; it will 

 be seen that the majority of the plaice dealt with were 

 between 9 and 11 inches in length. In the tables of 

 " particulars of fishes returned " the columns are 

 numbered in order to save space. The headings are: — 



1 



2 



3 



4 



5 6 



7 



8 



it 



Size when 



liberated 



(inches) 



U 



CM £ 



O 3 



Months in 

 the Sea 



Length 



when 



recaptured 



(inches) 



Increase 



in length 



(inches) 



Method of 

 recapture 



The lengths of the fishes when marked were 

 measured to the nearest quarter of an inch. The lengths 

 when returned were measured to the nearest eighth of an 

 inch. When only one or two fishes are returned in any 

 particular month an error may result from this difference 

 in the accuracy of the two measurements; but when 

 average growth-increments are calculated, and when these 

 are plotted on a curve, and the latter smoothed, such 

 inaccuracies disappear. The place of recapture is 



usually given as reported to me. It is generally unlikely 

 that it is accurate to within a mile or two, as a fish may 

 be caught anywhere during a drag of the trawl-net, which 

 may be of 20 or more miles in length in the case of a 

 steam trawler. As a rule, however, such inaccuracies 

 in position have no real significance. The values, 

 " months in the sea," have been obtained by subtracting 

 the number of the month of liberation from that of 

 recapture : they are calendar months. The letters under 

 heading 8, "method of recapture,'' denote: — ST, steam 



