532 \VM. A. KEPNER AND J. B. LOOPER. 



EXPLANATION* OF PLATE. 



FIG. i. Part of a section taken through plane indicated at a in text-figure. 

 A group of disintegrating interstitial cells is shown at b, c. a shows that already, 

 in this particular example, the superimposed ectoderm was but a single layer 

 thick. X 250. 



FIG. 2. Cell a of Fig. i, magnified to indicate the character of cell that forms 

 ovarian wall. X 1,250. 



FIG. 3. Cell b in Fig. i. Shows a disintegrating interstitial cell in which the 

 nucleus resembles a deutoplasmic granule. X 1,250. 



FIG. 4. Cell c in Fig. i. An attending interstitial cell in a more advanced 

 phase of disintegration than cell shown in Fig. 3. The nucleus no longer resembles 

 a deutoplasmic granule. X 1,250. 



FIG. 5. Section taken through plane indicated at b in text-figure. Shows 

 eleven pseudopodia closely applied to mesoglea. Yolk-formation has begun; it 

 is not, however, completed though all enlarged interstitial cells have disappeared. 

 X250. 



