530 ISLAND LIFE rARTii 



conjecture) must take such general permanence as a 

 starting-point., The whole inquiry into the phenomena 

 presented by islands, which forms the main subject of the 

 present volume has, I think, shown that this theory does 

 afford a firm foundation for the discussion of questions 

 of distribution and dispersal ; and that by its aid, com- 

 bined with a clear perception of the wonderful powers 

 of dispersion and modification in the organic world when 

 long periods are considered, the most difficult j^i'oblems 

 connected with this subject cease to be insoluble. 



