Jounson, — Nuclear Division. 
PLATE I. 
Vig. 1. Five cells of the serosa, two of them covered by the amnion, which is 
omitted from the rest of the figure for the sake of clearness. am., 
amnion; sr., serosa. X 150. 
Fig. 2. Section through the embryonal membranes and ovarian capsule. ‘The 
fibrous appearance of the ovarian capsule is due to the presence of 
muscle fibres and connective tissue. The boundary line between 
amnion and serosa is visible only in the vicinity of the amniotic 
nuclei. eth. fol., epithelium of ovarian capsule (when the plates were 
engraved I still took this to be the follicular epithelium, hence the 
error in the abbreviation); nl. fol., nucleus of capsular epithelium ; 
nl. sr., nucleus of serosa; nl. am., nucleus of amnion. X 630. 
Figs. 3-15 are all from the serosa. 
Fig. 3. Very small, binucleate cell. X 180. 
Figs. 4-10. Nuclei at different stages of division. vac., vacuole; x, new nuclear 
wall within the old one. X 550. 
Fig. 11. Two cells produced by division of a binucleate cell. X 130. 
Fig. 12. Cell from the serosa of a young embryo, with dividing nucleus; the axis 
‚ of elongation corresponds with the short axis of the cell. X 130. 
Fig. 13. Cell from serosa of a young embryo, with nucleus unequally divided and 
daughter nuclei eccentric in position. X 130. 
