212 



Part III. — Twenty-fourth Annual Report 



J Year, - 1*04 grammes, or J y oz. 



1£ „ - 13-1 



2g ,, - 97*4 ,, ,, 3| ,, 



H „ - 3807 „ „ 131 „ 



4£ „ - 2129 „ „ 4 lbs. Ui „ 



5J „ - 7000 „ „ 15 lbs. 10| „ 



The spawning period at Iceland is much the same as in the North Sea, 

 and Dr. Schmidt found that the cod of the last group, with an average 

 size of 88cm., and ranging from " a little under 70cm. and upwards," in 

 July, had spawned in the spring, while those of the group, with an 

 average of about 60cm. (24 inches), would spawn for the first time in the 

 following year. 



It may seem to one possible that the second group of small cod, with 

 an average size of 4J inches, might have been spawned in the spring of 

 the year, and that the smaller fish, taken on the north coast, have a 

 different rate of growth there. It must be remembered, however, as 

 Dr. Schmidt has so well shown, that the physical conditions, as tempera- 

 ture, vary very much at different parts of the coast of Iceland, and that 

 the life and wanderings of the cod are influenced thereby. He, moreover, 

 gives a table showing the growth of young cod at one place (Seydisf jord), 

 and all taken in this case with one apparatus, the eel-seine, between 23rd 

 May and 17th-23rd September, 1903. On 23rd May 180 measured 

 from 7cm. to 11cm., with au average of about 9cm. (3| inches) ; on 23rd 

 July 3300 measured from 10cm. to 17cm. (4-6| inches), the average size 

 being placed by him at 12cm. (4| inches), though it might perhaps be better 

 at 13cm.; on 17th-23rd September 1350 measured from 13cm. to 20cm. 

 (5|— 7J inches), the average being at 16cm. (6| inches). The first group 

 thus grew about 3cm. (1| inches) in the two months May-July ; in the 

 two months from July to September the growth amounted to 4cm 

 (1| inches), and in the whole period of four months it amounted to 7cm., 

 or 2| inches. In the September collection, moreover, 30 much smaller 

 cod were obtained, measuring 4cm. and 5cm. (l|-2 inches), and relating 

 these to the older group, and taking their average size at 4cm., the 

 growth over the winter would amount to only 5cm., or 2 inches, and from 

 September to September it amounted to about 12cm., or 4| inches. These 

 fish were caught between the shore and 5 fathoms depth. 



A collection made with the eel-seine, from the shore to 6| fathoms, on 

 9th September, 1903, at Vaagfjord, Suder, in the Faeroes, showed three 

 groups: — (1) The young of the same year, 277 in number, measuring 

 from 4cm. to 12cm. (1|-4|- inches), with an average size of about 7cm. 

 (2| inches) ; (2) a group of 87, measuring from 17cm. to 31cm. (6|-12| 

 inches), about 1| years old, or more, and with an average size of about 

 25cm. (9| inches) ; (3) a group of 5 cod, from 37cm. to 41cm. (14|-16g 

 inches). These results agree well with my own, and show an increase in 

 the year of about 18cm. (7^ inches). 



Recently a good deal of attention has been given, especially by German 

 investigators, to the growth of fishes as indicated by the markings on the 

 bones, otoliths, and scales. Mr. Stuart Thomson investigated the age of 

 cod by means of the markings on the scales. The specimens were taken on 

 26th August, and measured 20 9cm. (8J inches) and 25'lcm. (9-9 inches), 

 and the age determined in each case was about one year and 4-5 months ; 

 the fish were thus well on in their second summer's growth. The result 

 agrees with those obtained by me, as Mr. Thomson points out ; they tally 

 almost exactly with the collection on 22nd August, referred to in the 

 Table below. 



