128 Life and Love. 



complement of its own life. For, like other eggs 

 belonging to the higher forms of life, the complex 

 mammalian egg-cell is not alone, in itself, capable 

 of reproducing. It is a feminine cell, it contains 

 only part of the power to develop ; the full power 

 must come from union with its opposite; the male 

 element is needed to insure its development. 



The sperm-cells, it is scarcely necessary to add, 

 arc found in sperm-sacs corresponding to the 

 ovaries, in similar positions in the body-cavity of 

 the male. 



Ducts connect the sperm-sacs with the outer 

 world, and the structure at the terminus of these 

 ducts recalls a corresponding structure in the in- 

 sects, though all is far simpler here. Still, there is 

 external modification sufficiently developed to 

 effect the conveyance of the active sperm-cells to 

 a position sufficiently remote from the outer world 

 and sufficiently within the influence of the egg-cell 

 to result in its attaining its desired destination. 



The sperm-cell, transferred to this strange coun- 

 try by the union of the two sexes, cognizant in 

 some mysterious way of the existence of the )ct 

 distant egg-cell, begins its journey towards it, until 

 finally it meets the object of its search, unites with 

 it, and the two, having thus become one, enter 

 upon that wonderful growth which shall result in 

 reproducing the parent form. 



If for any reason the creature is isolated and the 

 egg-cell not fertilized, the egg continues its soHtarj' 



