Fig. 1 



Fig. 2 



^ \ ^ 



r:? 





Fig. 3 



Fig. 4 



Fig. 5 



'X^« 



Fig. 6 



Plate IV. Various stages in the development of the mature oocyte. 

 (From the Archives de Biologie.) 



Fig. 1, First maturation spindle — guinea pig. Fig. 2, Binucleated ovum, chro- 

 mosomes oriented for the metaphase of a mitosis — guinea pig. Fig. 3, Binucleated 

 ovum with formed maturation spindles — mouse. Fig. 4, Multinucleate cytoplasm — 

 mouse. Figs. 5 and 6, Typical uninucleate cleaved ovocytes. Fig. 6 shows deuto- 

 plasmic extrusions — guinea pig. 



58 



