128 AFRICAN GAME ANIMALS 



cured the elimination of the darker individuals. It is 

 infinitely more probable that the general tone of color is 

 due to the action of the climate — sunlight, moisture, and 

 temperature — on all the individuals of a great number of 

 species, generation after generation, and to the inheritance 

 of the characteristics thus chemically or mechanically ac- 

 quired. We believe that this is probably a clear case of the 

 inheritance of acquired characteristics. We have never felt 

 that the demonstrations (for instance of Cope, in his " Fac- 

 tors of Organic Evolution") of the occasional and limited 

 inheritance of acquired characteristics have been success- 

 fully refuted,* although we entirely agree with Dewar and 

 Finn in their masterly book on bionomics to which we have 

 already referred, "The Making of Species," that all the 

 facts tend to prove that the inheritance of acquired char- 

 acteristics is too rare and limited a phenomenon to make 

 it possible to regard it, any more than natural selection, 

 as a primary factor in the making of species. 



We saw in Africa one curious instance of the intrusion 

 into arid regions of a form normally belonging to an utterly 

 different environment. In East Africa we found the black 

 and white colobus monkeys in the depths of the cool, tall, 

 matted mountain forests. They lived in the tops of the 

 high trees, and came to the ground with much reluctance. 

 They never wandered out into the hot, dry country, where 

 plains of grass were dotted by scattered acacias, and palms 



* Recent experiments have demonstrated conclusively the inheritance in 

 guinea-pigs of acquired alcoholic characteristics; subtle Weismannic theorizing as 

 to germ-cells and plasma-cells, and hypothetical suppositions as to the infection 

 of the former, whether these theories and hypotheses have a scientific or merely 

 a mystical value, do not and cannot alter the proved facts (l) that these char- 

 acteristics were acquired, and (2) that they were inherited. 



II 



