Fig. 15 

 Rat primary oocyte and surrounding follicle cells showing 

 fluorescence induced by treatment with acridine orange and ultra- 

 violet irradiation. (The fluorescence shown by the eggs in Figs. 16, 

 25, 26, 35 and 36 was induced bv the same method.) X 500. 



Fig. 16 

 Rat tubal oocyte with second maturation spindle at metaphase. 

 : 500. 



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