The maturing process of ovocytes begins Mtii the single -layered follicle phase, therefore 

 on the basis of the existing data the percentage relationships of the quantity of maturing ovocytes In 

 various maturation stages of the ovaries will be the following (Table 5) . 



As la apparent from the data Introduced In Table 5 each maturation stage of the ovaries 

 corresponds to a specific percentage relationship of ovocytes of different growth phases . In the 

 ovaries of the VI maturation stage, moreover, there Is a certain quantity of empty follicles. 



The maturation process of ovaries is characterized, on the one hand, by a proportioned 

 increase in the weight (mass) of the ovaries and, on the other hand, by a disproportionate decrease 

 in the quantity of ovocytes In one and the same area . 



TABLE 5. VARIATION IN NUMBER OF OVOCYTES PER SQUARE MM. DURING 

 THE RIPENING (IN PER CENT OF NUMBER OF OVOCYTES IN THE 

 PHASE OF THE SINGLE -LAYERED FOLLICLE). 



TTie metiiod of coimtlng the ovocytes may be used as a supplementary method for an objective 

 evaluation of the maturity stages of the ovaries . With an average from a large number of observa- 

 tions, one may avoid transition stages, which are more ascribed, to unsufflclent knowledge, than 

 to tile objective state of the ovaries . 



A Comparative Characterization of Ovaries in Stage III from Mature 

 Herring and from Herring Maturing for the First Time 



From the microscopical Investigation of ovaries in stage HI, some conclusions may be 

 drawn of botii theoretical and practical interest. We have compared ovaries in stage in from her- 

 ring caught in the southern part of the Barents Sea with ovaries in the same stage from Greenland 

 Sea herring. The Barents Sea herring were 5-7 years old, those from the Greenland Sea, 7-13 

 years. 



From the microscopical preparations of ovaries in stage III, it has been stated that the her- 

 ring only stay in the Barents Sea until they have attained maturity. An exception Is the herring 

 found in the western part of the Barents Sea, along the bcrder-line of the Norwegian Sea, whereto 

 they migrate after the ffrst spawning. 



In herring from the southern part of the Barents Sea no empty follicles can be seen in the 



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