the western parts of the Barents Sea. 



This is fully in accordance with our ecological-physiological and histological investigations. 

 The males are the first to app2ar in the feeding areas after the spawning. The regeneration of the 

 gonads proceeds more rapidly in males than in females. The males' rate of feeding exceeds that 

 of the females, which fact leads to an Increase in the fat content and accordingly, to an increase 

 In the condition in comparison with the females . The numerical dominance of the males in the 

 Bear Island -Spitsbergen area In June and July is explained by the males' leaving the spawning 

 places before the females . 



from the middle of July, the numbers of males and females are equal in the samples, and 

 later the females even predominate . The equalization occurs to the same degree to which the 

 females emigrate from the spawning places . 



As is known, the spent herring after the spawning migrate to the western areas of the 

 Barents Sea (herring 6-7 years old) and northwards to the area near western Spitsbergen (7-14 

 years old). In this connection, the following rule may be of interest: the farther from the spawn- 

 ing place (Lofoten), towards the east, the Barents Sea, - and towards the north, - the area of west- 

 em Spitsbergen, - the later the numbers of males and females will be equal in the spent herring. 



At last we wlU draw some general conclusions . 



1 . Mainly young herring, which have not attained sexual maturity, spend the winter in the 

 eastern parts of the Barents Sea . The maturing herring is met with in small numbers In the cen- 

 tral area, and In large numbers in the western parts. 



2 . In spring, herring with developing sexual products are found In small numbers in the 

 western areas of the Barents Sea, along the border-line of the Norwegian Sea. 



3. The Murmansk herring spawns along the northwestern coast of Norway near the Lofoten 

 Islands and somewhat to the east and west. Spawning has also been observed nearS|Sr?<y. In the 

 western Barents Sea, spent herring appear in the catches in May. 



4. In summer, the herring In the Barents Sea are characterized by feeding herring in stage 

 n. In the adult herring, the regeneration of the gonads Is largely at an end in June. The maturing 

 of the sexual products begins in the 5- and 6-year-old herring, partly also in the 4-year-old indi- 

 viduals, characterized by the transition from stage II to III. 



5. In the autumn, the development continues, the gonads passing over from stage III to IV. 

 During the maturing, the herring migrate still farther towards the west, and at the end of the 

 winter they have reached the border-line of the Norwegian Sea, where they form pre-spawning 

 concentrations . 



The Stages of Maturity and the Conditions of the Medium 

 The Influence of the Temperature 



In order to understand an organism. It Is necessary to study its relation to the surroimding 

 medium. This question has been very slightly investigated with respect to the sexual cycle. We 

 .have therefore emphasized the study of the ripening of the sexual products in relation to the hydro- 

 graphical conditions. 



Of the hydrographlcal factors, we have only the possibility of studi^ng the temperature and 



235 



