THE P^DOGENETIC FLY, MIASTOR 53 



gradually becoming reduced as the oocytes increase in 

 size. Finally the oocyte (and accompanying nurse 

 cells), still surrounded by the follicular epithelium, 



n.c 



pPl 



13 



FIG. 12. Miastor americana. Longitudinal section through an ovary. 



en = envelop; /.ep = follicular epithelium; n.c = nurse chamber; 



n.c.n = nurse-cell nucleus; o.m = mesoderm; ooc.n = oocyte nucleus. 

 FIG, 13. Miastor americana. Longitudinal section through a nearly 



full-grown oocyte. g.v = germinal vesicle; n.c = nurse chamber; 



pPl = pole-plasm. 



