448 A. J. NICHOLSON 
Fig. 32. —Mitotic division in follicular epithelium cells during first period 
of growth. 
Fig. 33.—Degenerating follicular epithelium. 
Fig. 34.—Early stage of epithelial folding for foat formation. Some- 
what distorted section chosen as it clearly shows limits of epithelial cells. 
Fig. 35.—Later stage of folding. Float and outer wall with commence- 
ment of processes secreted. 
Fig. 36.—Commencement of differentiation of rosette-cells and produc- 
tion of ‘stopper’. Longitudinal section. 
Fig. 37.—Later stage of same. Nurse-cells degenerating. Longitudinal 
section. 
Fig. 38.—Transverse section of rosette-cells at same stage as 37. 
Fig. 39.—Longitudinal section. Degenerating nurse-cell nuclei shown 
partially surrounded by rosette-cells. 
Fig, 40.—Surface view of micropyle apparatus. 
Fig. 41.—Longitudinal section of anterior end of egg, showing section 
of micropyle apparatus and position of * stopper ’. 
