172 



Distances travelled — Under 10 miles. — Two fish, or 5*7 per cent,, were found at. 

 distances under 10 miles, 1, a male, at 5 miles, and a female at 4 J miles. 



10 to 20 miles. — Eight fish, or 22*8 per cent., were recaptured at distances of 

 from 11 to 19J miles, namely, 1, a male, which had migrated 15| miles to the south 

 and west, 1 to the south and east, and 3 to the north and west. 



Under 20 miles. — Thus, 10 fish, or 28*6 per cent., were found at distances under 

 20 miles, two males (16'6 per cent), with an average of 10 miles, and 8 females (34'8 

 per cent.), with an average of 16 miles. 



20 to 50 miles. — Twenty-three fish, or 65*7 per cent., were recaptured at dis- 

 tances of from 22 to 44 miles, viz. 10 males (83'3 per cent.), with an average of 31*5 

 miles, and 13 females (56"5 per cent.), with an average of 32*1 miles. Four 

 males and 6 females went to the north and west, 4 males and 3 females to the south 

 and west, one male to the south and east, 1 male and 4 female? to the north and east. 



50 to 100 miles. — One female was got at a distance of 54| miles to the west and 

 north (St. Andrews Bay). 



Over 100 miles. — One female was taken in the Moray Firth, at a distance of 

 123 miles. 



Matueity, 



Males. — The condition of the reproductive organs was known in 9 cases. Two 

 were "spawning," 1, which measured 37-5-38-9 cm., being taken in March 1913, 

 32^ miles to the south and west, ofi St. Abb's Head, and the other, of 33-5-42-1 cm., 

 in March 1915, offshore, at a distance of 25 miles north and east. 



Two were " ripe," 1, of 36-36-5 cm., taken in February 1913, 30| miles to the 

 westward, and the other, of 36-42-7 cm., in February 1914, to the south-east of 

 the Isle of May, at a distance of 39 miles to the westward. One was " nearly ripe " ; 

 it measured 35-5-402 cm., and was got in January 1914, near Aberdeen Bank, 

 at a distance of 29 miles to the north and west. 



Females. — The condition of the ovaries was recorded in 15 of the 24 cases. 

 None was " spa-wniing." One, of 42*5-43 cm., caught in February 1913, at Aber- 

 deen Bank, 37 miles to the north and east, was " nearly ripe." 



Three were "spent " ; 1, of 40-5-43-1 cm., caught in July 1913, 19| miles to 

 the south and west, and 2 taken in August 1913, 13 miles to the north and west ; 

 1, measuring 40-42-5 cm., and the other, 43-45-4 cm. Two were "half-ripe"; 

 1, of 40-5-40 cm., was got in October 1912, at Aberdeen Bank, and the other, of 

 44-43-3 cm., also taken in October 1912, 11 miles to the south and east. Among 

 the adult females whose ovaries were "immature" was 1, taken in April 1914, 

 17 miles to the north and west, and measuring 39-50 cm. 



Experiment at St. Andrews Bay. 

 3rrf December 1913. 



On 3rd December 1913, 59 plaice were marked and liberated in St. Andrews 

 Bay, namely, 34 males and 25 females, the Tay Fairway Buov lying N.E./PJ. 

 3 miles (Lat. 56° 23' N. ; Long. 2° 54' W. ; depth,' 11 fathoms). 



The fish used were caught by the " Goldseeker " in Kirkcaldy Bay on the 

 previous day. 



The sizes of the males ranged from 29-5 to 40-5 cm., and 8 were under the 

 adult size (33 cm.) when Hberated. The females ranged from 27*5 to 62-5 cm., 

 and 15 were under the adult size (38 cm.) on liberation. 



The numbers liberated and recaptured, arranged in 5-cm. groups, are as 

 follows : — 



Thirty of the marked plaice, or 50-8 per cent., were recaptured, comprising 

 19 males (55-9 per cent.) and 11 females (44 per cent.). 



