268 



Four were "nearly ripe," 1 taken in January 1913, in the Moray Firth, at a 

 cli»itance of 62 miles, another in December 1913, north of Rattray Head and south- 

 east of Noss Head, at 84 miles to the north and west, a third in January 1914, in 

 the Moray Firth, off Whitehills (Banff), a distance of 62 miles, and the fourth in 

 February 1914, after 700 days, near Kinnaird Head, at a distance of 44 miles to the 

 north and west. 



Three were described as " three-quarters ripe," 1 taken in November 1912, 10 

 miles to the south and west ; another also in November 1912, 22 miles to the north 

 and west, at Cruden Bay ; the third was recaptured in January 1914, after 678 

 days, at Whitehills, in the Moray Firth, at a distance of 62 miles. 



Three were said to be " half-ripe," 1 caught in March 1912, after 6 days, 11 

 miles to the south and west, and measuring 42-7 cm. ; another in April 1912, after 

 36 days, 23 miles to the north and west, and measuring 46'9 cm. ; the third, in 

 September 1913, 31 miles to the north and east, and measuring 52 cm. 



Among the females of adult size whose reproductive organs were " immature " 

 were the following captured within the Hmits of the spawning season : — One, measur- 

 ing 33'5— 42"2 cm., in January 1913, 21 miles to the north and east ; another, of 

 33-42-4 cm., taken in March 1914, in the Moray Firth, near Lybster, at a distance 

 of 97 miles ; and 1, caught in May 1913, 23 miles to the north and west, which 

 measured 43'4 cm. 



Among the females under adult size whose ovaries were " immature " were 2 

 taken in February 1913, and measuring respectively 33*5-37-6 cm. and 33-37-2 cm. 



EXPERIMKNT AT RaTTRAY HeAD. 



1th July 1912. 



At this place, which lies about 13 miles S. 79° E. from Rattrav Head, in Lat. 

 57'' 38' N. ; Long. 1° 25' W., where the depth is 40 fathoms, 101 fish were marked 

 and liberated, 46 males and 55 females. The males rn aged in size from 28-5 .o 45-5 

 cm., and 17 were under adult size whea liberated. The females measured from 

 29 to 48 cm., and 43 were under adult size on libeiation. 



The numbers liberated and reraptured, arranged in 5-cm. croups, are shown in 

 the following table : — 



The fish used in this experiment were trawled by the " (^oklseeker " in Kirk- 

 caldy Bay, Firth of Forth, on the 6th July, and were marked between 1.45 p.m. and 

 2.45 p.m., and then placed in tubs of running water. They were liberated on the 

 7th, at 4.10 a.m., 4 having died in the tubs. 



The number recaptured was 52, or 51*5 per cent., namely, 24 males (52-2 per 

 cent.) and 28 females (50-9 per cent.). Eighteen of the males were of adult size 

 on recapture, averaging 37*1 cm., and ranging from 33-8 to 45'9 era., as compared 

 with a mean of 35*1 cm., and a range of from 30 to 45-5 cm., on Uberation ; they 

 were at liberty for periods of from 26 to 738 days, the mean being 276 days ; they 

 migrated distances of from 11|^ to 74 miles, the mean being 41-2 miles, and the mean 

 rate of movement, 1*4 miles. Six of the males were under adult size, averaging 

 31-9 cm., as against 31*4 cm. on hberation ; they were free for a mean period of 

 119 days, and moved from 10 to 57f miles, the average being 26-5 miles, and the mean 

 rate of movement, per 10 days, 2-2 miles. 



Fifteen of the females were of adult size on recapture, varying from 38 to 46*2 

 cm., and averaging 41-1 cm., as compared with a range of from 32 to 41 cm., and an 

 average of 37 cm. on hberation ; their periods of Hberty varied from 17 to 1397 

 days, the average being 302 days ; tliey travelled distances of from 7| to 141 

 miles, the average being 35-1 miles, and the mean rate 1-2 miles per 10 days. 



