48 A STUDY IN HEREDITY 



malaria, their diseases did not always exterminate 

 the natives ; and, even when the latter did perish, 

 as in the West Indies, their place had to be filled, 

 not by pure Latins, but by half-breeds, and especi- 

 ally negro slaves, imported from West Africa, 

 where malaria is even more rife than in tropical 

 America. All these communities have revolted, 

 and San Domingo is now a Negro Republic, fore- 

 shadowing the fate of our Indian and West African 

 conquests. The Latins conquered, but, in a real 

 sense, could not colonize. The experience of Anglo- 

 Saxons in other parts of the world is similar. They 

 are able to colonize South Africa, because it is not 

 defended by virulent malaria, but they must share 

 its possessions with the natives, who, having under- 

 gone evolution against parasitic diseases, are not 

 exterminated thereby. And over their future hangs 

 the dark threat of native predominance. To West 

 Africa and India, the homes of malaria, they can go 

 only as conquerors. In a future, perhaps not very 

 remote, the natives, when sufficiently civilised, 

 will certainly expel their masters. In the savage 

 past, races exterminated one another with the 

 sword, now they do it with disease. And the 

 work done by disease is greater by far than any- 

 thing ever done by the sword. 



Historians have chronicled how Jew and Saxon 

 slew Canaanite and Briton, and entered into their 



