ee 
them remain during the following winter at this length, some, however, grow faster. 
During their third year, some at least of the year classes begin to associate themselves 
{| 
> 
Fig. 25. The Currents of the Norwegian Sea. From HELLAND-HANsEn and NANSEN. 
with the fat herring, and for the next two or three years, according to locality, they belong 
to the fat shoals. 
At an age of 4,5, or 6 years they separate from these, in the autumn, when the genital 
organs are beginning to develope; they are then “large” and in the following spring be- 
come “spring herring”. At this time they undertake migrations of greater or lesser 
extent, moving southwards along the coast, in a direction contrary to that in in which 
they as young fish were passively carried by the current. 
