No. I.] 



THE EMBRYOLOGY OF LIMULUS 



65 



EXPLANATION OF THE FIGURES. 



Reference Letters. 



Ovarian epithelium. 



Primitive cumulus. 



Polar globule ? 



Primitive groove. 



Primordial ovum. 



Protoplasmic processes. 



Segmental structures (glands or 

 sense organs?). 



Cell in process of delamination. 



Yolk. 



Junction of ectoderm and meso- 

 derm at the margin of the ger- 

 minal disc. 



