PLATE 2 



EXPLANATION OF FIGURES 



Pseudococcus 



16 and 17 Stages in differentiation of the three ovarian cellular elements, 

 namely, the nurse cells, egg cell, and follicular epithelial cells. 



18 A portion of transverse section through the egg chamber. 



19 Transverse section through the nurse chamber like the one represented 

 in figure 15. 



20 Longitudinal section of an ovariole somewhat older than the one repre - 

 sented in figure 17. 



21 A portion of transverse section of an ovarian egg. 



22 Longitudinal section of an early egg. 



23 A portion of longitudinal section through germinal vesicle. 



24 Longitudinal section of an egg when the germinal vesicle has reached the 

 periphery of the egg. 



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