THE SEXES, AND CRITICISM OF SEXUAL SELEC TION. 1 5 



the adult female, however, is quiescent, and bloated like a drawn-out 

 lemon. It may be asked, however, is not this merely the natural 

 nemesis of parasitism ? The life-history answers this objection: The 

 two sexes are at first alike — agile, and resembling most threadworms; 

 they become parasitic, and lose both activity and nematode form; but 

 the interesting fact is, further, that the male recovers himself, while 

 the female remains a victim. In other insect and worm types the 

 same story, in less accented characters, may be distinctly read. In 

 many crustaceans, again, the females only are parasitic; and while this 

 is in part explained by their habit of seeking shelter for egg-laying 

 purposes, it also expresses the constitutional bias of the sex. The 

 insect-order of bee-parasites {Streps ipter a) is remark- 

 able for the completely passive and even larval char- 

 acter of the blind parasitic females, while the adult 

 males are free, winged, and short-lived. Throughout 

 the class of insects there are numerous illustrations 

 of the excellence of the males over the females, 

 alike in muscular power and sensory acuteness. The 

 diverse series of efforts by which the males of so 

 many different animals, from cicadas to birds, sustain 

 the love-chorus, affords another set of illustrations of 

 preeminent masculine activity. 



Without multiplying instances, a review of the 

 animal 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 Fig. 6. 



. . - . Female Ckondrncinthtis, 



difference of habit, but even in the human species a parasitic Crustacean, 



..,,., with pigmy male (a) 



the contrast is recognized. Every one will admit that attached just above the 



,. , ... , origin of the long egg- 



StrenUOUS spasmodic bursts of activity characterize saC s (b\ of the female. 



men, especially in youth, and among the less civilized 



races; while patient continuance, with less violent expenditure of 



energy, is as generally associated with the work of women. 



For completeness of argument, two other facts, which will after- 

 wards claim full discussion, may here be simply mentioned, (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. (&) The same antithesis is seen, when we con- 

 trast, as we shall afterwards do in detail, the actively motile, minute, 

 male element of most animals and many plants with the larger pas- 

 sively quiescent female cell or ovum. 



