254 THE INTERNAL ENVIRONMENT OF THE BODY Part III 



195 1 ) have dealt with the relation of the function of the kidneys to the kind of 

 environment in which their owners Hve, and also with the evolution of the 

 vertebrate kidney in relation to the surrounding fresh or salt water, or the dry 

 land. His discussion of water regulation emphasizes the ecological significance 

 of the kidney, the part it has taken in limiting or extending the distribution of 

 animals. 



