]04 THE DESCENT OF MAN. [Part I. 



varied in a like manner. The variations at each succes- 

 sive stage of descent must, also, liave been in some man- 

 ner accumulated and fixed. 



The facts and conclusions to be given in this chapter 

 relate almost exclusively to the probable means by which 

 the transformation of man has been effected, as far as his 

 bodily structure is concerned. The following chapter will 

 be devoted to the develoi^ment of his intellectual and 

 moral faculties. But the present discussion likewise bears 

 on the origin of the different races or species of mankind, 

 whichever term may be preferred. 



It is manifest that man is now subject to much varia- 

 bility. No two individuals of the same race are quite 

 alike. We may compare millions of faces, and each will 

 be distinct. There is an equally great amount of diversity 

 in the proportions and dimensions of the various parts of 

 the body ; the length of the legs being one of the most 

 variable points.* Although in some quarters of the world 

 an elongated skull, and in other quarters a short skull pre- 

 vails, yet there is great diversity of shape even within the 

 limits of the same race, as with the aborigines of America 

 and South Australia — the latter a race " probably as pure 

 and homogeneous in blood, customs, and language, as any 

 in existence " — and even with the inhabitants of so con- 

 fined an area as the Sandwich Islands.^ An eminent den- 

 tist assures me that there is nearly as much diversity in 

 the teeth as in the features. The chief arteries so fre- 

 quently run in abnormal courses, that it has been found 

 useful for surgical purposes to calculate from 12,000 



' ' Investigations in Military and Anthropolog. Statistics of American 

 Soldiers,' by B. A. Gould, 1869, p. 256. 



* With respect to tbe " Cranial forms of the American aborigines," 

 see Dr. Aitken Meigs in 'Proc. Acad. Nat. Sci.' Philadelphia, May, 1S66. 

 On the Australians, see Huxley, in Lyell's 'Antiquity of Man,' 1803, p. 87. 

 Ou the Sandwich Islanders, Prof. J. Wyman, ' Observations on Crania,' 

 Boston, 1868, p. 18. 



