109 



length when it was recaptured, tlioiigh it liad migrated a distauee ul 74 miles, 

 and was eaught a little north of Buchanness, after 169 days. 



The remaining 2 fishes which were caught in February, both females, had 

 gone westwards into the Firth of Forth, very near-the place where they were origin- 

 ally taken, a distance of 22 or 22-5 miles ; they measured respectively 36-5 to 37-3 

 cm. and 33-5 ^o 34 cm. ; the former was " rather immature," and the latter " very 

 immature." 



We thus see that, as in other instances, the proportion recaptured to the north 

 increases with the increase of the period of liberty, and that it is clearly a spawning 

 migration. 



Third Quarter. — In March, April, and May, 7 fishes, or 10-9 per cent., were 

 recaptured, all to the north, the distances ranging from 36 to 238 miles, and averaging 

 ing 102 miles, while the mean rate of travel was 4-9 miles. Five were males and 

 2 were females, but the particulars of the position of recapture of a male and a 

 female were not ascertained. In March, a male, " nearly ripe," was caught 71 miles 

 distant, off Buchanness. In April, 3 males and 2 females were recovered. 

 One male was caught 64'5 miles distant, near Buchanness ; it was " spent " ; 

 another male had passed through the Pentland Firth, and along the whole north 

 coast of Scotland, and was caught 14 miles W.S.W. of Cape Wrath, 238 miles away, 

 after 208 days, having migrated at a mean rate of 11-5 miles per 10 days ; it was 

 " partly spent " ; the position where the third male was recaptured was not ascer- 

 tained. This was the case also with one of the females, and the other female, 

 measuring 35-5 to 36-6 cm., had moved least of all, and was caught after 211 days 

 36 miles to the north and east, off Tod Head ; it was " immature." One fish, a 

 male, was taken in May, after 261 days, only 2 miles north of the station ; it 

 measured 33 to 38-6 cm., and was "immature." In this quarter, therefore, the 

 movements revealed were the same as in the one previous, namely, to the north- 

 wards, and in connection with reproduction. 



Fourth Quarter. — In the next three-monthly period, 8 fishes, or 12-8 per 

 cent., were recaptured, 4 males and 4 females. Six, or 75 per cent., had 

 migrated to the north and east, for from 25 to 81 miles, the average being 46-6 

 miles, and thus the distances were much less than in the previous months ; the 

 mean rate of travel was 1-6 miles per 10 days. One had gone northwards for 12 

 miles, and 1 south and east for 14 miles. Of the 8 fishes caught, 7 were 

 taken in June, 5, 2 males and 3 females, to the north and east, mostly off the 

 coast of Aberdeen, and not so near the coast as the specimens in the earlier 

 part of the year, but more offshore, the distances ranging from 25 to 54 miles ; 

 1 of the other 2, a male, was got 12 miles to the westward, towards the mouth 

 of the Firth of Forth, and the remaining fish, also a male, 14 miles to the south and 

 east, oft" St. Abb's Head. The condition of the reproductive organs was ascertained 

 in 5 cases ; they were " immature," except 1 female, caught on 4th June 

 south-east of Aberdeen, 44 miles distant, which was " partly spent." None was 

 recaptured in August. 



Altogether, in the 12 montlis following hberation, 55 fishes, or 85-9 

 per cent, of the total recaptured, were again caught, viz. 23 males (76-7 

 per cent, of all males recaptured) and 32 females (95-9 per cent, of all 

 females). The position of capture was ascertained for all except 1 male and 5 

 females. Two had moved directly north for a distance of 2 miles ; 2 (42-9 

 per cent.) had migrated to the north and east ; 16 (32-7 per cent,) had gone to 

 the south and west ; 8 (16-3 per cent.) north and west, and 2 (4-1 per cent.) south 

 and east. 



I 'J ABLE 



