ORIGIN OF VELD AND KARROO PLANTS. 47 



Hottentot fig and many others, that they can live and 

 thrive in South Africa. 



The peculiarities of leaves, mentioned in the last 

 chapter, have likewise all been acquired in adaptation 

 to the prevailing drought. 



It was Darwin who gave us the clue to the " origin 



Fig. 24. — Anthe'ricum, with long fleshy 

 roots. 



of species" as above described. He called this in- 

 fluence of the surroundings " the direct action of the 

 conditions of life," the result, or effect, of which was, 

 that all the plants affected by it varied alike, i.e. in 

 adaptation to the new conditions of life, and so a '' new 

 variety " would arise. 



