PLATE 1 



EXPLANATION OP FIGURES 



Aglantha digitalis 



1 Portion of young ovary; shows entodermal epithelium of cavity of gonad, 

 oogonia and oocytes, two growing oocytes. X 615. 



2 Oogonium. X 2000. 



3 and 4 Oogonia from border of oocyte zone; probably in prophases of divi- 

 sion; fourteen loops present in figure 4. X 2000. 



5 and 6 Oogonia in last division; polar view of metaphase stage of division. 

 The sixteen chromosomes represent the diploid number. X 2000. 



7 Oocyte after growth has started. X 2000. 



8 Oocyte after considerable growth; nucleoplasm assuming a reticular con- 

 dition. X 2000. 



9 Growing oocyte showing chromatin bodies in the cytoplasm; nucleolus 

 non-chromatic. X 720. 



10 Growing oocyte, nuclear reticulum coarse and deeply staining; vacuola- 

 tion of cytoplasm beginning. X 720. 



11 Growing oocyte; extra-nuclear chromatin causing vacuolation of cyto- 

 plasm. X 720. 



630 



