60 
mentioned, and this was made the basis for marking out the incre- 
ments of growth actually observed to have been made by the marked 
plaice in known periods of time. When the chart referred to was 
published* I had only the results in the case of fish which had been 
free for less than a year. It will therefore be worth while here to 
append a comparison between the calculated size from the chart 
and the actual growth of the fish which have been caught after a 
long period of liberation. (See page 56.) 
Date of 
Liberation. 
Date of 
Recapture. 
Size 
Calculated. 
Actual. 
Difference. 
1803 
June 26 
1905 
Feb. 6 
Cm. 
37-5 
Cm. 
39-9 
Cm. 
+ 2-4 
July 15 
1904 
Dec. 17 
42 
44-2 
+ 2-2 
„ 15 
1905 
Jan. 12 
32 
29-6 
— 2-6 
„ 15 
Mar. 30 
32 
34-2 
+ 2-2 
„ 23 
„ 11 
34 
32-4 
— 1-6 
Aug. 4 
„ 20 
32-1 
32-1 
0 
„ 4 
Nov. 15 
39 
41-5 
+ 2-5 
„ 26 
Mar. 8 
33-5 
34-3 
+ 0-8 
The three which come nearest to my estimate of the growth of 
the plaice are those which had not migrated, and with one exception 
the plaice which had left the district showed an enhanced rate of 
increase. 
The age determination at which I arrived is one year in advance 
of other modern investigators. The different statements depend 
upon the existence or not of a group intervening between the 6 in. 
stage and the known shore stage. Both Fultonf and Wallace J: con- 
fess to its being but slightly represented, and further facts with 
regard to it are still required. 
The mesh of our trawl net is too large to demonstrate fully 
whether it is present in the Northumberland region or not, but at 
* Trans. Newcastle Nat. Hist. Soc, 190-1. 
+ Rep. Fish. Bd. for Scotland, for 1901. 
t Rep. North Sea Fish. Invest. Com., No. 2. 
