B 



mem, 



2 prort 



FIG. 62. The Maturation and Impregnation of the Animal Ovum. 



A, the ovum, surrounded by the vitelline membrane (mew), in the 

 act of forming the first polar cell (pot) : ? cent, centrosome. 



B, both polar cells (pol) are formed, the female pronucleus ( 9 frv*} 

 lies near the centre of the ovum, and one of several sperms is shown 

 making its way into the ovum at the micropyle (microp}. 



