Figure 5. Structure of annual rings of summer -spawning Iceland herring with sharply 

 marked first ring. 



Scale of herring at age 9 years, length 291 mm. 1 = 34 mm. male V stage of 

 maturity, first spawning in 7th year (sample 139, No. 19, 1951 - 17/IX). 



The increment for the first year, obtained as a result of inverse calculation, is near to the 

 direct measurements. According to the inverse calculation ij = 3.8 cm. , varying from 3.3 to 4.6 

 cm., according to the direct measurement it is 4.8 cm., varying from 4 to 5 cm . The observed 

 difference in the dimensions of one-ring herring, which was obtained from an inverse calculation 

 and direct measurements of the young, could arise as a result of the smallest of the young summer- 

 spawning herring escaping from the trawl . According to Fridriksson, the absolute length of the 

 young of herring at the age of 1 year and 5-6 months is 11.2 cm. (first ring according to Fridrik- 

 sson). According to the data of our calculation, the length of the young at this age, up to the middle 

 rays of the tail fin, is 9.2 cm. (in our method, second ring). If one takes into account the remarks 

 made above, then the growth rate in the first and second years, according to our data and Fridrik- 

 sson's material, is almost identical. 



The growth rate of the summer herring in the Faroes region, given in Table 4, does not 

 differ fundamentally from the data in Table 3. 



It is interesting to compare the growth rate of the spring- spawning race and the summer 

 herring in the first pjeriod of their lives . 



175 



