88 EVOLUTION 



retain an organization continuous in quality 

 with the original fferm-cfill from which the. 

 ^parent arose. They are thus not very liable 

 to be tainted by the mishaps which may befall 

 the "body" which bears them. And again, 

 in the life-history of the germ-cells, and in 

 the mingling of two of them of different 

 experiences in fertilization, t.hjgre_is appar- 

 opportunity for new orga.yn'n 



porrihiTin.tirms variation in short. 

 Perhaps there is some subtler advantage 

 still in the process which ensures that-each 

 new life usuall beins in 4n\ifi.cation of 



The third aspect of the problem is that 

 rnulticellular organisms are 



females. The former liberate male elements, 

 which are usually actively motile; the latter 

 form, and usually liberate, more passive egg- 

 cells or ova. In the ]f>wf r refl{ ^hfifi QJ 

 animal kingdom f-lum* seldom 



ence between males and jepiales : indeed, it is 

 often impossibleTo distinguish the two sexes 

 without a microscopic examination of the 

 reproductive organs. It is obviously at this 

 level, and not with the highly specialized sex 

 dimorphism of peacock and peahen, ruff and 

 reeve, lion and lioness, man and woman, 

 that the problem should be first studied. 

 The problem is partly solved by con- 



