^ KINGSLEY. 



DESCRIPTION OF PLATE V. 



Figs, i, 2. Sections (longitudinal and transverse) through a portion of the liver 

 and ovary of a Limulus four inches in length, showing the formation of the primordial 

 ova and the intrusion of older ova between the ovarian epithelium and tunica 

 propria. 



Fig. 3. Section of an egg one hour after impregnation, showing a possible polar 

 globule. 



Figs. 4, 5, 6. Surface views of eggs four hours after impregnation, showing the 

 peculiar segmentation of the surface previous to true segmentation. Fig. 6 is a polar 

 view of the egg shown in Fig. 4. 



Fig. 7. Section through an egg of four hours, showing the peripheral columns, 

 distinctly cut off in most regions from the central yolk. 



Fig. 8. A portion of the egg in Fig. 7, more enlarged. 



Fig. 9. Projection of an egg with eight nuclei. 



Figs. 10-14. Surface views of successive stages of surface division. 



Fig. 15. Section of an egg in early segmentation showing cleavage planes at one 

 pole of the egg. 



Fig. 16. Projection of an egg with twenty-six nuclei. 



Fig. 17. Enlarged view of a superficial cell in early segmentation showing the 

 peripheral protoplasm (blastema) and protoplasmic processes extending down be- 

 tween the blastomeres. 



Fig. 18. Egg at the close of early segmentation, before the differentiation of ecto- 

 mesoderm. 



Fig. 19. Section of an egg during the process of delamination. 



