52 



were under adult size when they were liberated. The numbers liberated and 

 recaptured, arranged in 5 cm. groups, are as follows : — 



The fish used were trawled by the " Goldseeker " at Station VI. (the " Fluke 

 Hole ") off St. Monans, Firth of Forth, on the same day as they were marked 

 and hberated. 



The number recaptured was only 24, or 46*2 per cent,, viz. 9 males (56*2 per 

 cent.) and 15 females (42-9 per cent.). All the 9 males were of adult size, when 

 recaptured, the range being from 36"4 to 41*4 cm., and the average 37'9 cm., as 

 compared with a range of 29 to 34*5 cm., and an average of 31*2 cm., when they 

 were liberated ; the periods of freedom varied trom 241 to 711 days, the mean 

 being 467 days ; the distances migrated were from 18J to 218 miles, averaging 

 87*6 miles, and the mean rate of movement per 10 days was 1*8 miles. Eleven 

 of the females were of adult size on recapture, the average length being 43*9 cm., 

 and the range froin 38*4 to 48"4 cm. ; on liberation, the sizes were from 32 to 

 47"5 cm., v/ith an average of 37*9 cm. ; the periods of liberty varied from 108 to 

 1220 days, and averaged 466 days ; the distances migrated were from 5 to 153 miles, 

 the mean being 60-5 miles, and tlie average rate of travel, per 10 days, 1*2 miles. 

 The four females, under the adult size, had an average length of 32 cm. on 

 liberation and 36*3 cm. on recapture ; the periods of freedom were from 42 to 394 

 days, and averaged 251 days, and the distances migrated varied from 6 to 38| 

 miles, and averaged 23'6 miles, while the mean rate of movement was '89 mile. 



The Extent and Direction op Migration. 



First Quarter. — Only 1 fish was taken in the 3 months following hberation, a 

 female in June, after 42 days, got near Largo, in Fife, Firth of Forth, 6 

 miles distant ; its size on recapture is not recorded, but it measured 35-5 cm. on 

 Hberation. 



Second Quarter. — Only 2 fish were taken in this quarter, both females. The 

 position of recapture of 1 is unknown ; the other was taken within the Firth, near 

 Burntisland, 16 miles to the westward, in August, after 125 days ; it was an adult, 

 measuring 38-42 cm. and is described as " half-ripe." 



Third Quarter. — Two fishes only were recaptured in this quarter, a female in 

 November, which measured 34-37*1 cm., the position of recovery being unknown, 

 and a male, of 29-5-36-8 cm., which was taken in December, after 241 days, ofi 

 Tod Head, to the north and east, at a distance of 50 miles ; it was described as 

 " three-quarters-ripe." 



Fourth Quarter. — The number recaptured in this quarter, which embraces the 

 spawning period, was larger, viz. 8 fishes. Five were caught in February 1912, 



4 males and a female. The male, measuring 32-5-36-5, was caught, after 296 days, 

 7 miles west from Strathie Point, on the north coast of Scotland, at a distance of 

 218 miles, the mean rate of movement being 7-4 miles per 10 days ; it was " nearly 

 ripe." One of the females, of 39-5-40-8 cm., was captured, after 288 days, in 

 the Moray Firth, 18 miles south-east of Noss Head, a distance of 153 miles ; it was 

 " spawning " (" partly spent "). Another female, measuring 44-5-46 cm., was 

 caught north-east of Rattray Point, at a distance of 115 miles. The other 2 females 

 were taken in the Firth of Forth, north-east of Pittenweem, at distances of 4 and 



5 miles, after 304 and 301 days ; they measured 35-38-4 cm. and 34-40-6 cm., 

 and both were " immature." 



