314 SEXUAL SELECTION: MAN. [Part IL 



then she would probably transmit these qualities chiefly 

 to her adult daughters. The whole body of women, how- 

 ever, could not be thus raised, unless during many genera- 

 tions the women who excelled in the above robust virtues 

 were married, and produced offspring in larger numbers 

 than other women. As before remarked with respect to 

 bodily strength, although men do not now fight for the 

 sake of obtaining wives, and this form of selection has 

 passed away, yet they generally have to undergo, during 

 manhood, a severe struggle in order to maintain them- 

 selves and their families ; and this will tend to keep up or 

 even increase their mental powers, and, as a consequence, 

 the present inequality between the sexes. 5 



21 



Voice and Musical Powers. — In some species of Quad- 

 rumana there is a great difference between the adult sexes, 

 in the power of the voice and in the development of the 

 vocal organs ; and man appears to have inherited this dif- 

 ference from his early progenitors. His vocal cords are 

 about one-third longer than in woman, or than in boys ; 

 and emasculation produces the same effect on him as on 

 the lower animals, for it " arrests that prominent growth 

 of the thyroid, etc., which accompanies the elongation of 

 the cords." 25 With respect to the cause of this difference 

 between the sexes, I have nothing to add to the remarks 

 made in the last chapter on the probable effects of the 

 long-continued use of the vocal organs by the male under 

 the excitement of love, rage, and jealousy. According 



24 An observation by Yogt bears on this subject : he says, it is a " re- 

 markable circumstance, that the difference between the sexes, as regards 

 the cranial cavity, increases with the development of the race, so that tho 

 male European excels much more the female, than the negro the negress 

 WeJcker confirms this statement of Huschkc from his measurements of 

 negro and German skulls." But Vogt admits (' Lectures on Man,' Eng 

 translat. 1864, p. 81) that more observations are requisite on this point, 



25 Owen, ' Anatomy of Vertebrates,' vol. iii. p. 603. 



