_ 30 — 



Figiz 1906, APRILS 



However it was only 

 for a third of the catch, 

 chiefly consisting of the 

 larger individuals that he 

 was able to ascertain the 

 age, so that here too the 

 values are probably a little 

 high. It may be noted that 

 in this case the values were 

 even higher than the ones 

 obtained from area G. 



Figs. 17 — 20 show the 

 relation between the various 

 sizes in a number of catches 

 on the Dogger Bank. These 

 were all made in April; the 

 first (fig. 17) in 1906; the 

 three others (figs. 18-20) in 

 1903. A few vertical lines 

 have been introduced: the 

 unbroken lines show the 

 average length in April 

 according to the growth- 

 curve for D (fig. 15), and 

 the broken lines show the 

 average length as per the 

 growth-curve for G. These 

 lines practically coincide as 

 far as groups I and II are 

 concerned, but in the case 

 of groups III and IV there 

 is a considerable difference. 

 The group in fig. 17 coin- 

 cides nicely with the II 

 group in both areas. In 

 the other three figures the 

 groups agree in all essentials 

 with groups III and IV from 

 G, but not with the corre- 

 sponding groups from D. 

 In fig. 19 especially there 

 is an indication of an over- 

 lapping of G's III and IV 



Fig. 17— 20. Different catches of haddock on the Dogger Bank, from the '^•^ r^f r>'c TTT o-rnnn 



month of April (1903 and 1906). The vertical lines denote the lengths groups ana 01 U S Hi group, 

 n April as found by the growth-curves from areas D and G (see Fig. 15'. If we Compare the CUrveS 



Ltn&TM in CE.rHTinE.TQRS 



