4D 



All the plaice used in this oxpetiuicut were traA\ led by the " Goldsecker " 

 at Station VI., Firth of Forth, on the same day as they were marked and 

 liberated. 



The number recaptured was 30, or 60 per cent., 19 (65"5 per cent.) being males, 

 and 11 (57-9 per cent.) females. 



Of the 19 males, 14 were of adult size, when recaptured, the sizes ranging from 

 35'4-39"2 cm., and averaging 37'1 cm., whereas, on Hberation, the average size 

 was 3r7 cm., and the range, from 28*5-35 cm. ; their periods of liberty ranged from 

 90 to 1247 days, the mean being 445 days ; they migrated distances of from 4i 

 to 168 miles, the average distance being 67*6 miles, and the mean rate of movement 

 1-4 miles per 10 days. 



The average size of the 5 males under adult size on recapture was 28 cm., and 

 on liberation 29 cm. ; the mean period of freedom was 29 days, and the distances 

 migrated, from 4^ to 13^ miles, the average bein%' 7'4 miles, and the mean rate 

 of movement 2"5 miles per 10 days. 



Of the 11 females. 6 were of adult size on recapture, the sizes ranging from 38'3 

 to 41 cm., and averaging 40" 1 cm., while on hberation the range was 30-37 cm., 

 and the mean 33'9 cm. ; the periods of freedom varied from 184 to 458 days, aver- 

 aging 361 days ; the distances migrated were from 5 to 46 miles, the mean being 

 25'9 miles, and the mean rate, per 10 days, '7 mile. The average size of the other 

 5 females was 33*7 cm., on recapture, and 31*6 cm. on liberation ; the periods of 

 freedom varied from 22 to 472 days, and the average was 151 days ; the distances 

 migrated ranged from 5 to 33| miles, the mean being 14 miles, and the average rate 

 of movement, per 10 days, '9 mile. 



The Extent and Direction of Migration. 



First Quarter. — One fish, a male, of 28-27*6 cm., was recaptured in March 1911, 

 after 7 days, off Anstruther, in the Firth of Forth, at a distance of 6 miles. 



In April, 3 were taken, 2 males and a female, all -wdthin the Firth of Forth, and 

 all under the adult size. One of the males was got after 20 days, off Buckhaven, 

 at a distance of 7 miles ; the other male was caught, after 35 days, off St. Monans, 

 at a distance of 4 miles ; while the feiia'e was taken, after 22 days, off Pitteu\vee)ii, 

 at a distance of 5 miles. 



In May, 2 males and 1 female were recaptured, all within the Firth of Forth, 

 and all under adult size. One of the males was found, after 41 days, off Anstruther, 

 at a distance of 6 miles ; the other was caught, after 44 days, 13 miles to the west- 

 wards, near Pettycur (east of Burntisland) ; while the female was got, after 45 days, 

 off Largo, at a distance of 6 miles. 



Two were recaptured in June, a male and a female, both under adult size. The 

 male was caught off St. Monans, at a distance of 4 miles, after 90 days, and the 

 female, off Pettycur, 13 miles to the westwards, after 73 days. 



Thus, all the fish recaptured to the end of June 1911, 9 in number, or 30 per cent, 

 of the total recaptured, were taken wthin the Fiith of Forth, and all were consider- 

 ably under adult size, both on liberation and recapture. They were all taken on the 

 north coast of the Forth (Fifeshire). 



Seco)id Quarter. — None was recaptured in July, but 2 were taken in August. 

 One of these, a female, which measured 33-35*5 cm., was caught, after 146 days, 

 within the Firth of Forth, in the South Bay, near Cockenzie, at a distance of 11 

 miles ; the other, a male, which measured on hberation 35 cm., but whose size 

 on recapture was not recorded, had moved out of the Forth, and was taken to the 

 eastwards, at a distance of 17 miles, after 145 days. 



Two were recovered in ScDtember. A female, of 35-38*3 cm., was found, after 

 184 days, eastwards of the Isle of May, at a distance of 26 miles ; the other was a 

 male, of 32*5-36*5 cm., which was caught, after 176 days, in the same locality 26 

 miles distant ; both were " immature." 



Third Quarter. — Two were taken in October 1911, both males ; 1, of 31-35*9 

 cm., was caught oft" Montrose, at a distance of 43 miles to the north-east, after 222 

 days ; and the other, measuring 32-35*6 cm., was caught, after 224 days, in the 

 same locahty, but a little farther north, at a distance of 50 miles ; both were de- 

 scribed as " nearly ripe." 



