FIG. 104. Maturation and Fertilization in Nereis 



A, egg with germinal spot; B, egg with first spindle forming, sperm-cell small ; 

 C, egg with first spindle at periphery, two sperm-centrosomes ; I), egg with 

 one polar cell formed, spindle with sperm-cell ; E, egg with second polar cell 

 formed, spindle from sperm-centrosomes ; f, first cleavage spindle, first 

 stage of embryo 



(From Wilson's The Cell) 

 212 



