*&? 



Figure 11. — Growth and maturation of gizzard shad eggs. 



mm. size, the oocyte's cytoplasm is stained by 

 both hematoxylin and eosin — the resulting red- 

 dish-purple oocyte is clearly noticeable among the 

 bluish-purple smaller oocytes. The nuclear mem- 

 brane and chromatin material surrounding the 

 pink-staining nucleoplasm appear fuzzy as though 

 disintegrating. Oil globules have formed in the 



periphery of the cytoplasm beneath the follicle 

 cells that have become cuboidal. 



Stage 5. — In this stage the oocyte with its 

 envelope of follicle cells — now columnar — grows 

 from 0.30 mm. to about 0.45 nun. The nuclear 

 membrane has largely disintegrated, and chro- 

 matin material has all but lost its discreteness. 



410 



U.S. FISH AND WILDLIFE SERVICE 



