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mean being 39 days ; the distances migrated varied from 5 to 10 miles, and averaged 

 7 miles. Of the 33 females, 17 were of adult size on recapture ; the sizes on libera- 

 tion were from 32 to 50-5 cm., the average being 38-5 cm., and on recapture from 38"6 

 to 49-8 cm., the mean being 41-6 cm. They were at liberty for from 1 to 862 days, 

 the average being 196 days ; they migrated distances of from 4 to 91 miles, with a 

 mean distance of 14'3 miles, and the average rate per 10 days was -87 mile. Sixteen 

 were under 38 cm. on recapture, the average length being 34.1 cm., and the average 

 on liberation 32-1 cm. ; the periods of freedom ranged from 2 to 680 days, the 

 mean being 135 days ; the distances migrated were from 5 to 33 miles, averaging 

 12-3 miles, and the mean rate per 10 days -9 mile. 



The Extent and Direction op Migration. 



First Quarter. — In May, 7 of the marked fishes were recaptured, 3 males and 4 

 females. Five of them were taken to the south and west, at distances of from 5 to 

 11 miles, the one which was taken at 11 miles being caught on the following day ; 

 1 had moved south and east for 5 miles, and another north and west for 9 miles. 

 Three of the females measured 44, 44, and 50-5 cm. respectively, and were " spent " ; 

 the fourth, of 28*5 cm., was " immature." 



Nine were recaptured in June, 4 males and 5 females ; 2 were taken at 9 miles 

 to the soutli and west, 3 at 6, 7, and 11 miles to the northwards, 2 at 6 and 8 miles 

 to the south and east, and 2 at 5 and 6^ miles to the north and east. All the females 

 were iinder 38 cm. ; 3 of the males were above 33 cm. 



Eleven were recaptured in July, 5 males and 6 females ; 6 were taken to the 

 south and west at distances of from 4 to 17 miles ; 1, 10 miles to the south and east ; 

 1, 4 miles directly east ; and 3, 12, 15, and 18 miles to the north and west. 



Thus the number recaptured to the end of July was 27, or 45-8 per cent, of the 

 total recaptures. One had gone directly east, 2 (7*4 per cent.) north and east, 

 7 (26 per cent.) north and west, 4 (14'8 per cent.) south and east, and 13 (48" 1 per 

 cent.) south and west. 



Second Quarter. — In August, September, and October, 14, or 23-7 per cent., were 

 taken, viz. 5 males and 9 females, and the positions of recapture of all but 1 of the 

 females was ascertained. Two had gone directly west for 4 and 8 miles, 1 went 

 south and east for 5 miles, 2 north and west for 12 and 15 miles, 3 north and east 

 for 12, 17, and 56 miles, and 5 (38-4 per cent.) south and west for from 5 to 14 miles. 



Third Quarter. — Only 2 were recaptured in the next 3 months, viz. a male, 

 " fully half-ripe," in December, off Aberdeen, at a distance of 54 miles, and a 

 female, " immature," in January 1913, 5 miles to the south and west. 



Fourth Quarter. — Nine, or 15-2 per cent., were got in this quarter, 4 in February, 

 3 in March, and 2 in April. One was taken 5 miles to the south-west — a female 

 of 39 cm. and " immature " ; 2, both males, were got to the north-west, 1 at a 

 distance of 15 miles, and the other in the Firth of Forth, at a distance of 23 miles ; 

 the former was " spawning," and the latter " immature." Five were found to 

 the north-east, 4 off the coast of Aberdeen, at distances of from 33 to 91 miles ; 2, 

 both males, were " spawning " or " ripe " ; the fifth was taken at a distance 

 of 21 miles in the saine direction. The remaining fish is reported to have been 

 recaptured 163 miles E. i N. of Flamborough Head (Lat. 55° 5' N. ; Long. 4° 10' 

 E.) on the 15th March 1913, after 309 days, the distance migrated being 219 miles 

 S. 55° E. It was a male, measuring 30-5 cm. on liberation and 38'8 cm. on re- 

 capture ; the condition of the testes was not ascertained. 



Altogether, in the 12 months following liberation, 52 fishes were caught, or 88*1 

 per cent, of the total number recaptured, viz. 23 males (88'5 per cent.) and 29 

 females (87-9 per cent.). The position of recapture of 51 was ascertained ; 11 

 (21-6 per cent.) went to the north and east, and the same number to the north 

 and west ; 1 was got directly east, and 2 directly west ; 6 (11-8 per cent.) were 

 taken to the south and east ; and 20 (39*2 per cent.) to the south and west. 



[T.iBLE. 



