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Fishery Bulletin 92(4), 1994 



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Figure 6 



Appearance of advanced yolked oocytes of Atlantic croaker, Micropogonias 

 undulatus. (A) healthy (nonatretic) oocyte; (B) oocytes in early stage of a atresia; 

 (C) oocyte in intermediate stage of a atresia; (D) oocytes in late stage of a 

 atresia. N=nucleus; Zr=zona radiata; Pc=peripheral cytoplasm; La=late stage 

 of a atresia. Bars=0.1 mm. 



bution of maturity stages and the pattern of oocyte 

 development is presented in Figure 8. The cycle can 

 start either with immature females, which enter the 

 cycle for the first time by reaching sexual maturity, 

 or with adult resting females, which restart the cycle 

 by entering the developing stage at the beginning of 



each spawning season. After the first batch of ad- 

 vanced yolked oocytes is completed, females, now in 

 the fully developed stage, go through a smaller cycle 

 (spawning phase) that characterizes the pattern of 

 multiple spawning and indeterminate fecundity of 

 Atlantic croaker. During this phase, fully developed 



