30 



FOOT-NOTES TO EVOLUTION. 



itself would be without meaning or explanation. The 

 essential argument in favour of " Darwmism " is that it 

 brings all biological facts into unison from whatever 

 field of investigation these facts may be derived. How- 

 ever much evolutionists have at times 



very act as seemed to drift away from Darwin's con- 

 a meaning. , . ... , 



elusions, It IS always the most accurate 



research and the sanest thought which come nearest the 



opinions set forth in the Origin of Species. The body 



of facts has grown enormously year by year, but the 



conclusions we must accept are substantially those laid 



down by Darwin himself. 



The facts of " geographical distribution," for exam- 

 ple, have a meaning to us when we view them as the 

 results of centuries of the restlessness 

 Geograp ica ^^ individuals. Each species of animal 



distribution. , , , , • , , 



or plant has been subjected to the vari- 

 ous influences implied in the term "natural selection," 

 and under varying conditions its representatives have 

 undergone many different modifications. Each species 

 may be conceived as making each year inroads on terri- 

 tory occupied by other species. If these colonies are 

 able to hold their own in the struggle for possession 

 they will multiply in the new conditions and the range 

 of the species becomes widened. If the surroundings 

 are different, new species or varieties may be formed 

 with time, and these new forms may again invade the 

 territory of the parent species. Again, colony after 

 colony of species after species may be destroyed by 

 other species or by uncongenial surroundings. 



Only in the most general way can the history of any 

 species be traced ; but, could we know it all, it would 

 be as long and eventful a story as the history of the 

 colonization and settlement of North America by immi- 

 grants from Europe. Each region where animals or 



