THE STRUGGLE FOR THE LIFE OF OTHERS. 249 



Undoubtedly sex then had physiological advantages ; 

 but when in a later day the ethical advantages become 

 visible, and rise to such significance that the higher 

 world nearly wholly rests upon them, we are entitled, 

 as viewing the world from that higher level, to have 

 our own suspicions as to a deeper motive underlying 

 the physical. 



Apart from bare necessity, it is further remarkable 

 that no very clear advantage of the sex-distinction has 

 yet been made out by Science. Hensen and Yan 

 Beneden are able to see in conjugation no more than a 

 VerjUngu7ig or rejuvenescence of the species. The 

 living machinery in its wearing activities runs down 

 and has to be wound up again ; to keep life going some 

 fresh impulse must be introduced from time to time ; 

 or the protoplasm, exhausting itself, seeks restoration 

 in fertilization and starts afresh. ^ To Hatschek it is 

 a remedy against the action of injurious variations; 

 while to Weismann it is simply the source of varia- 

 tions. " I do not know," says the latter, " what mean- 

 ing can be attributed to sexual reproduction other 

 than the creation of hereditary individual characters 

 to form the material on which natural selection may 

 work. Sexual reproduction is so universal in all 

 classes of multicellular organisms, and nature deviates 

 so rarely from it, that it must necessarily be of pre- 

 eminent importance. If it be true that new species 

 are produced by processes of selection, it follows that 

 the development of the whole organic world depends 

 on these processes, and the part that amphigony 

 has to play in nature, by rendering selection 

 possible among multicellular organisms, is not only 

 ^ Geddes and Thomson, The Evolution of SeXj p. 163. 



