124 Darwin, and after Darwin. 



He had six attendants, who all died, and eventually their head- 

 man, called Charura, was elected chief by the Basango. In 

 the third generation he had sixty able-bodied spearmen as lineal 

 descendants. This implies an equal number of the other sex. 

 They are very light in colour, and easily known, as no one is 

 allowed to wear coral beads such as Charura brought except the 

 royal family. A book he brought was lost only lately. The 

 interest of the case lies in its connexion with Mr. Darwin's 

 celebrated theory on the ' origin of species,' for it shows that an 

 improved variety, as we whites modestly call ourselves, is not so 

 liable to be swamped by numbers as some have thought." 



Here we have a perfect fulfilment of what I last year, in 

 ignorance of this observation of Livingstone's, predicted as being 

 likely to occur in such a case. We have the whitish aristocracy 

 in a dominant condition, and evidently in a fair way to spread 

 their characteristics over a larger area and give rise to a marked 

 variety, and it had clearly struck Livingstone fourteen years 

 before the theory of physiological selection had been heard of, 

 just as it must strike us now, as an instance telling strongly 

 against the " swamping " argument as used by Flemming Jenkin 

 and Romanes. 



Here we have a curious example of one writer 

 supporting the statements of another, while appear- 

 ing to be under the impression that he is controvert- 

 ing those statements. Both Professor Herdman's 

 imaginary case, and its realization in Livingstone's 

 account, go to show " the tendency of the members 

 of a variety to breed with one another." This is 

 what I have called " psychological selection," and, 

 far from "ignoring" it, I have always laid stress 

 upon it as an obviously important form of isolation 

 or prevention of free intercrossing. But it is a form 

 of isolation which can only occur in the higher animals, 

 and, therefore, the whole of Professor Herdman's 

 criticism is merely a restatement of my own views 

 as already published in the paper which he is 



