118 ''The Descent of Man" 



corrected. A large ear with a point is shoAvii in the pliotograph^, 

 but it can easily be demonstrated — and Deniker has ah-eady pointed 

 this out — that the figure is not that of an orang-foetus at all, for that 

 form has much smaller ears with no point ; nor can it be a gibbon- 

 foetus, as Deniker supposes, for the gibbon ear is also without a 

 point. I myself regard it as that of a Macacus-embryo. But this 

 mistake, which is due to Nitsche, in no way afiects the fact recognised 

 by Darwin, that ear-forms showing the point characteristic of the 

 animal ear occur in man with extraordinary frequency. 



Finally, there is a discussion of those rudimentary structures 

 which occur only in one sex, such as the rudimentary mammary glands 

 in the male, the vesictda prostatica, which corresponds to the uterus 

 of the female, and others. All these facts tell in favour of the 

 common descent of man and all other vertebrates. The conclusion 

 of this section is characteristic : " It is mily our natural jyrejudice, 

 and that arrogance which made our forefathers declare that they 

 were descended from demi-gods, which leads us to demur to this 

 conclusion. But the time will before long come, tvhen it ivill he 

 thought wonderful that naturalists, who were ivell acquainted ivith 

 tJie comparative structure and develojyment of man, and other 

 mammals, shoidd have believed that each was the work of a separate 

 act of creationV 



In the second chapter there is a more detailed discussion, again 

 based upon an extraordinary wealth of facts, of the problem as to 

 the manner in which, and the causes through which, man evolved 

 from a lower form. Precisely the same causes are here suggested for 

 the origin of man, as for the origin of species in general. Variability, 

 which is a necessary assumption in regard to all transformations, 

 occurs in man to a high degree. IMoreover, the rapid multiplication 

 of the human race creates conditions which necessitate an energetic 

 struggle for existence, and thus afford scope for the intervention of 

 natural selection. Of the exercise of artifcial selection in the 

 human race, there is nothing to be said, unless we cite such cases as 

 the grenadiers of Frederick William I, or the population of ancient 

 Sparta. In the passages already referred to and in those which 

 follow, the transmission of acquired characters, upon which Darwin 

 does not dwell, is taken for gi-anted. In man, direct effects of 

 changed conditions can be demonstrated (for instance in regard 

 to bodily size), and there are also proofs of the influence exerted 

 on his physical constitution by increased use or disuse. Reference is 

 here made to the fact, established by Forbes, that the Quechua- 

 Indians of the high plateaus of Peru show a striking development 



1 Descent of 31 an, fig. 3, p. 24. » Ibid. p. 86. 



