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particulars of the sizes on recapture were ascertained for 8 ; they ranged from 

 34-4 to 42-4 cm. and averaged 37-8 cm. ; the periods of Uberty varied from 37 to 

 1073 days, the average being 318 days ; the distances migrated were from 5 to 

 176 miles, the average being 79'4 miles, and the mean rate per 10 days 2-5 miles. 

 Particulars were obtained with regard to 16 of the 19 females recaptured, of which 

 12 were of adult size and 7 under adult size ; the periods of liberty of the former 

 ranged from 25 to 999 days, and averaged 341 days ; their sizes ranged from 

 38-5 to 44-8 cm., the average being 41-6 cm. ; they migrated distances of from 



4 to 174 miles, the average being 40*8 miles and the mean rate of travel was 1 mile 

 per 10 days. The seven immature females were free for an average period of 

 119 days ; their sizes on recapture ranged from 29-7 cm. to 37 cm., the mean 

 being 34-5 cm. ; the distances migrated ranged from miles to 34 miles, the average 

 being 14-6 miles, and the mean rate of travel per 10 days was 1*1 miles. 



The Extent and Direction of Migration. 



First Quarter. — Three fish, 2 females and a male, were recaptured in May, but 

 particulars were ascertained only for 1 of the females ; it had moved 5 miles to 

 the south and west in 25 days, and was "immature." In June, 6 were recaptured, 

 2 males and 4 females, all " immature," but the position of recapture of 1 of the 

 females was not ascertained. The two males had moved to the south and west 

 for distances of 5 and 19 miles. One female had also gone in this direction for 



5 miles. Another had moved for 7 miles to the south and east, and the other 

 female had gone to the north and west for a distance of 12 miles. Three, all 

 females, were caught in July, but the position of recapture of 1 Avas not ascer- 

 tained. One of these, measuring 35 cm., was caught at the place where it was 

 liberated, after 88 days ; the other, measuring 36-5 cm., had gone back to the 

 Firth of Forth, near to the locality where it was originally caught, a distance of 

 26 miles, at an average rate of 3'3 miles per 10 days. 



Thus, 12 of the marked fishes (or 42*8 per cent, of the total number recaptured) 

 were taken in May, June, and July, but particulars in regard to them were ascer- 

 tained for only 7. Four (57 per cent.) had moved south and west for an average 

 distance of 9 miles, the average rate being 2 miles per 10 days ; 2 had gone north 

 and west, the average distance being 19 miles, and the mean rate 2*5 miles ; the 

 remaining fish went south and east for 7 miles. 



Second Quarter. — Four fishes (14-3 per cent.) were recaptured in August, 

 September, and October, 3 respectively at 4, 6, and 9 miles from the station ; the 

 fourth fish had migrated a distance of 44 miles to the north and east, well off- 

 shore, in 148 days, at an average rate of 2-9 miles. 



Third Quarter. — Only 2 (7-1 per cent.) were recaptured in this quarter, both 

 males, 1 in November and 1 in December. The former was caught in St. Andrews 

 Bay, 23 miles distant to the west and north ; it measured 39'9 cm., and was " nearly 

 ripe." The other male was taken to the north, off the coast of Aberdeen, 56 miles 

 distant, after 240 days, and it was " three-quarters ripe." 



Fourth Quarter. — Two of the marked fish, both males, were recaptured in 

 February 1912, 1, measuring 36 cm., in the Moray Fiith, 126 miles distant, and 

 the other, measuring 38*4 cm., south-east of Start Point, Orkney, 176 miles distant ; 

 the latter was " nearly ripe," but the condition of the testes of the other was not 

 determined. The mean rate of travel of these fishes was respectively 4*1 and 

 6 miles. 



Ihus, in the 12 months following liberation, 20, or 71*4 per cent., were re- 

 captured, viz. 7 males (77-7 ]3er cent.) and 13 females (68-4 per cent.). Particulars 

 as to direction and distance were ascertained for 15 of them, viz. 4 (26'7 per cent.) 

 had gone north and east, and the same number north and west ; 2 (13*3 per cent.) 

 went south and east ; and 5 (33-3 per cent.) moved south and west. 



LTable. 



