163 



349 cm., and a range of 30 to 40 cm., on liberation. The periods of liberty varied 

 from 24 to 794 days, the mean being 285 davs. The distances migrated were from 

 6^ to 247 miles, the average being 65'7 miles, and the mean rate of movement, per 

 10 days, 2-3 miles. 



Four of the males were under the adult size on recapture, the average being 

 31"9 cm., as compared with 32*1 cm. on Hberation. The mean period of freedom 

 was 31 days, and the average distance migrated 28*7 miles, the mean rate being 

 9"1 miles per 10 days. 



Twenty of the females were of adult size on recapture, the average being 42-6 cm., 

 and the ange from 38'3 to 50'6 cm., as compared with an average of 37"5 cm., and 

 a range of 29'5 cm. to 47-5 cm. on liberation. The periods of freedom were from 

 63 to 1011 days, the mean being 431 days. The distances moved were from 14i to 

 131 miles, the average being 40"1 miles, and the mean rate -9 mile. 



Nineteen of the females were under the adult size when recaptured, namely, 

 from 29'5 to 37*7 cm., averaging 33'7 cm., as compared with a range of 29 cm. to 

 37"5 cm,, and a mean size of 32' 1 cm. on liberation. They were at liberty for from 

 17 to 591 days, the average bemg 195 days, and the distances travelled varied from 

 19 to 57 miles, the average being 34' 1 miles, and the mean rate, per 10 days, 1-9 

 miles. 



The Extent and Direction op Migration. 



First Quarter. — Three males and 3 females were recaptured in July, all to the 

 south and west, mostly towards the mouth of the Firth of Forth, and the coast 

 south of it. One of the males, measuring 33-32*6 cm., was taken, after 9 days, 

 east of St. Abb's Head, at a distance of 19| miles ; another, of 32'5-3r6 cm., was 

 got, after 17 days, 15 miles distant ; a third, measuring 37'5-37"l cm., was re- 

 covered, after 24 days, north of St. Abb's Head, at a distance of 38| miles. Of the 

 females, one, of 34"5-33"l cm., was taken, after 18 days, 20| miles distant ; 

 another, of 29-29-5 cm., after 24 days, east of the Isle of May, at a distance of 34 

 miles ; and the third, which measured 31'5-30'7 cm., after 17 days, nearly east of 

 Longstone Light, at a distance of 26J miles. The mean rates of movement of 

 these fish were from 8*8 to 21-6 miles per 10 days. 



A male and 2 females were recaptured in August ; the male, of 31-32-2 cm., 

 after 39 days, off the mouth of the Firth, at a distance of 39^ miles to the south 

 and west ; one of the females, of 31 -31 "2 cm., after 39 days, in the same locality, 

 at a distance of 36 miles ; and the other female, measuring 31*5-32 cm., after 

 44 days, a little to the east of the Isle of May, at a distance of 42 miles to the west. 



Six were recaptured in September, 3 males and 3 females. One of the males, 

 of 33-34-2 cm., had migrated 10 miles directly west in 78 days ; another, of 32-31-5 

 cm., was found off Fife Ness, at a distance of 41 miles, after 61 days ; the third 

 male, of 37-37 cm., was taken, after 69 days, to the south east of Tod Head, at a 

 distance of 26 miles to the north and west ; one of the females, of 44-43 cm., was 

 got, after 63 days, to the north-east of Longstone Light, at a distance of 32 miles 

 to the south and west ; another, of 30-5-31 cm., was caught, after 76 days, 22| miles 

 to the south and west, towards the Firth of Forth ; the remaining female, of 35- 

 35*5 cm., was recaptured, after 71 days, far offshore, to the south-east of Buchan- 

 ness, at a distance of 57 miles to the north and east. 



In the first quarter, therefore, 15 of the marked plaice, or 21-1 per cent,, were 

 taken, 10 (66-7 per cent.) to the south and west ; 2 (13-3 per cent.) to the north 

 and west ; 2 to the west, and 1 to the north and east. 



Second Quarter. — Three males and 1 female were recaptured in October, the 

 female, of 32-5-33-6 cm., after 91 days, 19 miles to the north and west ; 1 of the 

 males, measuring 35-34*7 cm., was taken, after 94 days, 11 miles to the south and 

 west ; another, of 34-5-36-4 cm., was recaptured, after 107 days, off the Moray 

 Firth, to the south-east of Noss Head, at a distance of 126 miles ; the remaining 

 male, which was 45 cm. on liberation, but whose size on recapture was not recorded, 

 was taken, after 114 days, to the south-east of Longstone Light, at a distance of 

 71 miles to the south and east. 



Three females and 2 males were taken in November, all described as " im- 

 mature." One of the males, of 36-5-36-7 cm., was caught, after 137 days, north- 

 east of Longstone Light, at a distance of 26 miles to the south and west ; the 



