Figure 7. StrucUire of first ring of summer -spawning herring. First ring weakly marked. 

 Characteristic are the fragmented sclerites IJU corresponding to the growth of 

 the first year scale . 



Table 5 gives data for the growth of the summer -spawning herring in comparison with the 

 spring-spawning Atlantic -Scandinavian herring. The lag in growth of the summer herring in the 

 first year of its life is to be explained by the shorter growing period . 



In ensuing years, the observed lag in growth Is levelled out, and by 8 or 9 years the spring 

 and summer herrings hardly differ in size . 



Fertility and Time of Onset of Sexual Maturity 



On the basis of the material treated, one can state that some individuals of the summer race 

 reach sexual maturity at the age of 3 to 4 years, the sexually mature at this age being mostly males. 



In the general mass of herrings, the gonads mature in the 5th and 6th years, when the body- 

 length is 25-27 cm. 



In order to determine the fertility of the summer -spawning herring, we used 25 specimens 

 cau^t in late June and early July 1951 to the north-east of Iceland and 52 specimens caught, on May 

 20, 1954, to the north-east of the Faroes. 



In these samplings, all the individuals had developed gonads. In the sampling from the 

 Iceland region, the herrings were at the V and VI gonad maturity stage. 



177 



