252 METHODS AND RESULTS OF ETHNOLOGY. 



were than that they were not — what a wonderfully 

 efficient " Emigration Board " must have been at 

 work all over the world long before canoes, or even 

 rafts, were invented; and before men were impelled 

 to wander by any desire nobler or stronger than 

 hunger. And as these rude and primitive families 

 were thrust, in the course of long series of genera- 

 tions, from land to land, impelled by encroach- 

 ments of sea or of marsh, or by severity of summer 

 heat or winter cold, to change their positions, what 

 opportunities must have been offered for the play 

 of natural selection, in preserving one family varia- 

 tion and destroying another! 



Suppose, for example, that some families of a 

 horde which had reached a land charged with the 

 seeds of yellow fever, varied in the direction of 

 woolliness of hair and darkness of skin. Then, if 

 it be true that these physical characters are accom- 

 panied by comparative or absolute exemptions 

 from that scourge, the inevitable tendency would 

 be to the preservation and multiplication of the 

 darker and woollier families, and the elimination of 

 the whiter and smoother haired. In fact, by the 

 operation of causes precisely similar to those which, 

 in the famous instance cited by Mr. Darwin, have 

 given rise to a race of black pigs in the forests of 

 Louisiana, a negro stock would eventually people 

 the region.* Again, how often, by such physical 



[* Mr. Pearson, in his very interesting work On Na- 

 tional Life and Character, justly dwells upon the ob- 



