18 
the number so taken is shown to the ri^ht of tlie symbol used 
for each bay wliere the tisli were liberated. Xo attempt has 
been made on the charts to indicate the time taken to make 
the mifji-ation, but this factor is stated in the tables, and full 
particulars are f?iven in preceding? reports. 
Plaice . — Table 1, ('hart 1. — The total number liberated 
was 5dl, and of these 470 were dealt with in lOOd, 7 in 1004, 
and o4 in 1900. The reca])tures numbered 76 or 14 per cent. 
(Only 0 were obtained which show migration of ovei- 10 
miles. Of the fish captured at a distance of less than 5 
miles from the place of lil>eration 57 were accounted for in 
the first year and the remainder (7) in the second year. The 
amount of migration is not, however, controlled altogether 
by the ])eriod of liberation, tor amongst those migrating over 
10 miles 6 were captured in the first year — one travelling 
42 miles in less than six months, another 51 miles in less than 
five months, and the third 65 miles in eleven months. 
Amongst the remaining (i which left the district are 6 
for which the locality of recapture is unknown. They were 
sent from Ab(‘rdeen, (itrimsby, and London respectively. 
These fish must have left the district, in fact thej* must have 
migrated to a consid(>rable distance to he captured by any but 
local trawlers. 
The general direction of migration for the six, of which we 
have the information as to locality (with one exception which 
was caught 20 miles E.S.E. from the place of liberation), is 
northerly, one going as far as the Moray Firth in less than 
two years. 
From I'able 5 it is evident that the determining factor in 
migration is approaching maturity. The mean size of the 
plaice which left the district is 65'8 cm., the smallest being 
20 cm. The mean size of those which did not leave the 
district is 26'6 cm., the largest being 34'6 cm. 
r Reports, 1903, p. 36; 1904, p. 72; 1905, p. 56 ; 1909, p. 17. 
Ihih . — Table 2, Chart 2. — The total number liberated was 
768. (Of these 0 were set free in 1906, 462 in 1004, 290 in 
1005, 28 in 1006, and 0 in 1007. The number recaptured 
was 67, or 4'8 per cent. Only 7 had migrated more than 10 
miles, 5 of them being captured in the first six months. 
