PH" 



Fig. 5 Miastor americana; diagram showing the entire germ cell cycle, cl.n., 

 cleavage nucleus; ex.chr., extruded chromatin; oog, oogonium; p.b, polar body; 

 p.g.c, primordial germ cell; p.o, primary oocyte; p. pi, 'polares Plasma'; st.c, 

 stem-cell. 



394 



