3 o PROBLEMS OF GENETICS 



form local races which appears in the species of Further India. 

 Are we not then on safer ground in regarding the fixity of our 

 species as a property inherent in its own nature and consti- 

 tution? Just as in ages of domestication no rose has ever given 

 off a blue variety so has the pheasant never broken out into the 

 polymorphism of the Ruff. 



As soon as it is realised how largely the phenomena of vari- 

 ation and stability must be an index of the internal constitution 

 of organisms, and not mere consequences of their relations to 

 the outer world, such phenomena acquire a new and more 

 profound significance. 



