214 THE DESCENT OF MAN, Part I. 



CHAPTEK VII. 



On the Races of Man. 



The nature and value of specific characters — Application to the races 

 of man — Arguments in favour of, and opposed to, ranking the 

 so-called races of man as distinct species — Sub-species — Mono- 

 genists and polygenists — Convergence of character — Numerous 

 points of resemblance in body and mind between the most distinct 

 races of man — The state of man when he first spread over the 

 earth — Each race not descended from a single pair — The ex- 

 tinction of races — The formation of races — The effects of cross- 

 ing — Slight influence of the direct action of the conditions of life 

 Slight or no influence of natural selection— Sexual selection. 



*n 



*& 



It is not my intention here to describe the several 

 so-called races of men; but to inquire what is the 

 value of the differences between them under a classi- 

 ficatory point of view, and how they have originated. 

 In determining whether two or more allied forms 

 ought to be ranked as species or varieties, natu- 

 ralists are practically guided by the following con- 

 siderations ; namely, the amount of difference between 

 them, and whether such differences relate to few or 

 many points of structure, and whether they are of 

 physiological importance ; but more especially whether 

 they are constant. Constancy of character is what is 

 chiefly valued and sought for by naturalists. Whenever 

 it can be shewn, or rendered probable, that the forms 

 in question have remained distinct for a long period, 

 this becomes an argument of much weight in favour 

 of treating them as species. Even a slight degree of 

 sterility between any two forms when first crossed, or 

 in their offspring, is generally considered as a decisive 



