THE EVOLUTION OF SEX. 



kingdom, or a perusal of Darwin's pages, will amply confirm the 

 conclusion that on an average the females incline to passivity, 

 the males to activity. In higher animals, it is true that the 

 contrast shows rather in many little ways than in any one 

 striking difference of habit, but even in the human species the 

 contrast is recognised. Every one will admit that strenuous 

 spasmodic bursts of activity characterise men, especially in 

 youth, and among the less civilised races ; while patient con- 

 tinuance, with less violent expenditure of energy, is as generally 

 associated with the work of women. 



Both sexes of a Flea — the Jigger or Chigoe {Sarcopsylla penetrans) ; the 

 female much swollen with eggs. — From Leuckart. 



For completeness of argument, two other facts, which will 

 afterwards claim full discussion, may here be simply mentioried. 

 {a) At the very threshold of sex-difference, we find that a little 

 active cell or spore, unable to develop of itself, unites in 

 fatigue with a larger more quiescent individual. Here, at the 

 very first, is the contrast between male and female, {b) The 

 same antithesis is seen, when we contrast, as we shall afterwards 



