218 THE DESCENT OF MAN. 



of the stamens; and in the Algas, &c., by the locomotive power 

 of the antherozooids. With lowly-organized aquatic animals, 

 permanently aiExed to the same spot and having their sexes sep- 

 arate, the male element is invariably brought to the female; and 

 of this we can see the reason, for even if the ova were detached 

 before fertilization, and did not require subsequent nourishment or 

 protection, there would yet be greater difficulty in transporting 

 (hem than the male element, because being larger than the latter, 

 they are jiroduced in far smaller numbers. So that many of the 

 lower animals are, in this respect, analogous with plants."' The 

 male of affixed and aquatic animals having been led to emit 

 their fertilizing element in this way, it is natural that any of 

 their descendants, which rose in the scale and became locomotive, 

 should retain the same habit; and they would approach the female 

 as closely as possible, in order not to risk the loss of the fertiliz- 

 ing element in a long passage of it through the water. With some 

 few of the lower animals, the females alone are fixed, and the 

 males of these must be the seekers. But it is difficult to under- 

 stand why the males of species, of which the progenitors were 

 primordially free, should invariably have acquired the habit of 

 approaching the females, instead of being approached by them. 

 But in all cases, in order that the males should seek efficiently, 

 it would be necessary that they should be endowed with strong 

 passions; and the acquirement of sucli passions would naturally 

 follow from the more eager leaving a larger number of offspring 

 than the less eager. 



The great eagerness of the males has thus indirectly led to their 

 much more frequently developing secondary sexual characters 

 than the females. But the development of such characters would 

 be much aided, if the males were more liable to vary than the 

 females— as I concluded they were— after a long study of domes- 

 ticated animals. Von Nathusius, who has had very wide experi- 

 ence, is strongly of the same opinion.^^ Good evidence also in 

 favor of this conclusion can be produced by a comparison of 

 the two sexes in mankind. During the Novara Expedition'^ a 

 vast number of measurements was made of various parts of the 

 body In different races, and the men were found in almost evsry 



=1 Prof. Sachs ("Lehrbuch der Botanik,* 1870, s. 633) in speaking of 

 the male and female reproductive cells, remarks, "verhalt sich die 

 "eine bei der Vereinlgung activ, . . . die andere erscheint bei der 

 Vereinigung passiv." 



^ 'Vortrage uber Viehzucht,' 1872, p. 63. 



^ 'Reise der Novara: Anthropolog. Theil,' 1867, s. 216-269. The re- 

 sults were calculated by Dr. Weisbach from measurements made by 

 Drs. K. Soherzer and Schwarz. On the greater variability of the 

 males of domesticated animals, see my 'Variation of Animals and 

 Plants under Domestication,' vol. ii. 1868, p. 75. 



