2 INTRODUCTION. 



the nature of the affinities which connect together whole groups 

 of organisms — their geographical distribution in past and present 

 times, and their geological succession. The homological struc- 

 ture, embryological development, and rudimentary organs of a 

 species remain to be considered, whether it be man or any other 

 animal, to which our attention may be directed; but these great 

 classes of facts afford, as it appears to me, ample and conclusive 

 evidence in favor of the principle of gradual evolution. The 

 strong support derived from the other arguments should, however, 

 always be kept before the mind. 



The sole object of this work is to consider, firstly, whether 

 man, like every other species, is descended from some pre-exist- 

 ing form; secondly, the manner of his development; and thirdly, 

 the value of the differences between the so-called races of man. 

 As I shall confine myself to these points, it will not be necessary 

 to describe in detail the differences between the several races — an 

 enormous subject which has been fully discussed in many valu- 

 able works. .The high antiquity of man has recently been demon- 

 strated by the labors of a host of eminent men, beginning with 

 M. Boucher de Perthes; and this is the indispensable basis for 

 understanding his origin. I shall, therefore, take this conclusion 

 for granted, and may refer my readers to the admirable treatises 

 of Sir Charles Lyell, Sir John Lubbock, and others. Nor shall 

 I have occasion to do more than to allude to the amount of differ- 

 ence between man and the anthropomorphous apes; for Prof. 

 Huxley, in the opinion of most competent judges, has conclusively 

 shown that in every visible character man differs less from the 

 higher apes, than these do from the lower members of the same 

 order of Primates. 



This work contains hardly any original facts in regard to man; 

 but as the conclusions at which I arrived, after drawing up a 

 rough draft, appeared to me interesting, I thought that they might 

 interest others. It has often and confidently been asserted, that 

 man's origin can never be known: but ignorancs more frequently 

 begets confidence than does knowledge: it is those who know lit- 

 tle, and not those who know much, who so positively assert that 

 this or that problem will never be solved by science. The con- 

 clusion that man is the co-descendant with other species of some 

 ancient, lower, and extinct form, is not in any degree new. La- 

 marck long ago came to this conclusion, which has lately been 

 maintained by several eminent naturalists and philosophers; for 

 instance, by Wallace, Huxley, Lyell, Vogt, Lubbock, Biichner, 

 RoUe, &c.,' and especially by Hackel. This last naturalist, besides 



' As the works of the first-named authors are so well known, I need 

 not give the titles; but as those of the latter are less well known in 

 England, I will give them:— 'Sechs Vorlesungen uber die Darwin'sohe 



