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Part III. — Twenty-fourth Annual Report 



seven months of age, approximately 4 J inches in length, the size varying 

 from about 3 inches to about 7| inches, and in December they were of 

 much the same size. It was estimated that the growth during the second 

 year amounted to about 16 7cm., or a little over 6J inches; that the 

 average size of a cod when about two years of age was approximately a 

 little over 13 inches; when about three years old about 20 inches; and 

 when four years old about 27 or 28 inches ; and that though some might 

 reach a size equal to that of sexually mature males when three years of 

 age, the great majority, and perhaps all, would not spawn till they were 

 about four years old. 



Since the publication of my paper on the growth of the cod, in the 

 Annual Report for 1900, a number of investigations have been made on 

 the same subject, which may be briefly referred to. 



Dr. Petersen gave an estimate of the growth, in Danish waters, as 

 follows : — In its first year it is between 1 and 8 inches long ; in its 

 second between 10 and 18; in its third between 20 and 30; and in its 

 fourth year 30 inches and longer; and he states that this rate of growth 

 is somewhat similar to what is given by me in the above paper. Measure- 

 ments are not given by Dr. Petersen, except in certain cases, viz., of fish 

 taken at the end of March by line, and two groups are shown — first, one 

 in which the first year has been completed, and which measure from 

 about 9cm. to about 22cm. (3J-9| inches) ; and second, a group which 

 have completed two years, and measure approximately from 27cm. 

 to 52cm. or 53cm. (10|-20^ inches), the maximum number in each 

 group being massed about 15cm. or 16cm. (6-65 inches) and 36cm. to 

 39cm. (14|-15| inches); while cod above 52cm. or 53cm. (20| inches) 

 are described as of greater age.* 



In several of his papers dealing with the Norwegian fishery investiga- 

 tions, Hjort has given an account of the rate of growth of the cod. A 

 length of between 8cm. and 16cm. (3|-5g inches) is assigned to it in its 

 first year, and between 18cm. and 24cm. (7J-9| inches) in the second 

 summer of its life, when it is about 1^ years old, which agrees with my 

 results. In a table of measurements of cod taken on the south-west 

 coast of Norway in August, the following sizes are shown : — (1) a group, 

 about six months old, from 4 cm. to 13cm. (l§-5g inches), most 

 measuring 6cm. (2) A group, about 1| years old, from 16cm. to 30cm. 

 (6^-11 | inches), and most about 25cm. (9| inches). (3) A group, 

 about 2| years of age, from 32cm. to 42cm. (12|-16| inches). All 

 these groups agree with my own determinations. t 



In another work on Norwegian fisheries, Hjort, referring to the cod on 

 the coast of Finmarken, distinguishes four age-groups : — (1) One year old, 

 about 20cm. long (7g inches). (2) When two years old, and known as 

 '* Finmarken cod" or " Lodde cod," and forming an important fishery on 

 the Finmark coast, to which a length of 50cm., or 19| inches, is assigned. 

 (3) A group, at least three years of age, comprising the largest cod, and 

 forming the basis of the "Skrei" fishery, and measuring about 70cm. in 

 length (27 1 inches) + It seems to me that the two last groups are probably 

 too large ; they do not, at least, agree with the rate of growth in the North 

 kSea. No details of the measurements are furnished, except in a diagram, 

 which shows the measurements of the Finmarken cod in April, and of 

 the larger cod on the Malangsgrunden. A growth of 30cm. (llf inches) 

 in a year from the first to the second group seems excessive. 



In another paper, Hjort refers to the Danish investigations on the 

 " Thor," referred to below, and mentions that with the cod taken by the 



* Report of the Danish Biological Station, IX., pp. 4, 30. 



f Hjort and Dahl, Fiskeforsog i Norsk e Fjorde, pp. 75, 77. 

 X Fiskeri og Hvalfangst i det Nordlige Norge, pp. 50-53. 



