THE EVOLUTION OF MAN 



A HUMAN OVUM, 



bisected and strongly magnified. Its actual size is that of a 

 dot barely visible to the naked eye. This ovum, when detached 



from the female ovarium, represents a genuine " cell." It is 



surrounded by a membrane, which is penetrated by the male 



sperm-cell in the act of fertilization. The soft interior mass 

 contains a large " nucleus." 



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