-48 



Aberdeen, at a distance of 70 miles in November 1911, and the other, north of St. 

 Abb's Head, in October 1911. One male was said to be "about half-ripe " ; it 

 was caught in August 1912, after 545 days, 34 miles distant, to the north-east of 

 St. Abb's Head. All these fish were over the adult size on liberation. 



Six males were " immature." Four were over the adult size when liberated, 

 and they were caught in June, July, August, and September— months well without 

 the limits of the spawning season ; 1 was caught ]iear Fair Isle, 1 in the Moray Firth, 

 1 off Buchanness, and 1 north-east of May Isle ; the other 2 were under adult size 

 when liberated, and were both taken in the Firth of Forth, at a distance of 5 miles 

 from the Station, in February and March 1912, after 383 and 391 days ; they 

 measured respectively 29-33'3 cm., and 29-35"8 cm., so that the latter was above 

 the average adult size during the spawning season, and was yet " immature." 



Females. — The condition of the ovaries was determined in 23 of the 29 females 

 recaptured. One, measuring 49'5-50"2 cm., was " beginning to spawji " ; it was 

 caught off Aberdeen, at a distance of 62|^ miles, in March 1911, after 50 days, the 

 mean rate of movement being 12*5 miles per 10 days. 



None of the females was described as " ripe." 



Seven were " spent " ; 6 were above adult size on liberation. The largest of 

 all, measuring 45"5-5r9 cm., was taken in July 1913, after 889 days, off Kirkcaldy, 

 in the Firth of Forth, about 10 miles distant ; 1 was caught in the Moray Firth, off 

 Clyth Ness, in May 1912, and another off Aberdeen, at a distance of 81| miles, in 

 April 1912 ; 3 were taken off the Isle of May, at 18, 281 and 43^ miles, in March 1911, 

 February 1911, and July 1912 ; the seventh spent female was found in April 1914, 

 after 1148 days, 53 miles to the south and east, off Holy Isle ; it measured 32'5 cm., 

 when liberated and 47'5 cm. on recapture. 



One female, measuring 37-45 cm., was described as " three-quarters ripe " ; 

 it was caught in September 1912, off Rattray Head, 110 miles to the northwards. 

 Two were " half ripe," 1 taken in August 1912, off the coast of Aberdeen, 77^ miles 

 distant, and the other off Rattray Head, in August 1912, at a distance of 105 miles ; 

 they measured respectively 35*5-43"6 cm., and 3r5-43-3 cm. 



Seven females above adult size on recapture were described as " immature " ; 

 3 were taken in the month of June, 2 in the month of July, 1 iii August, and 1 in 

 December, all to the north and east. Five females, which were under the adult 

 size on recapture, were caught in March and April 1911, 4 of them in the Firth of 

 Forth, at distances of from 3 to 5 miles, and 1 off the coast of Aberdeen, at a dis- 

 tance of 59^ miles, after 45 days. 



One fish, whose sex is not recorded, but which from its size was probably a 

 male, is described as " spawning " ; it was caught in March 1911, after 51 days, at 

 a distance of 78| miles to the south-east, off the coast of Northumberland ; it 

 measured 35-35*2 cm. 



EXPERIMENT III. 



2.181 March \%\l. 



In this experiment, only 50 fishes were marked and liberated, viz. 29 males. 

 19 females, and 2 whose sex was not determined. The sizes of the males ranged 

 from 27-5-38 cm., and of the females, from 26-5-37 cm., while the 2 of undistin- 

 guished sex each measured 34 cm. Nineteen of the males and 19 of the females were 

 under the adult size when liberated. The numbers Uberated and recaptured, 

 arranged in 5-cm. groups, are shown on the accompanying table : — 



