|lu{LII8RARY . 



v^\ - /i 



THE PROBLEMS OF EVOLUTION 



INTRODUCTION 



We are reminded by a recent writer that "the 

 problems of evolution are much broader than the 

 origin of biological species," ^ and with this warn- 

 ing in mind I must confess to a limitation of my 

 subject and of my present interest. Admittedly 

 evolution is inclusive of universal processes, not 

 all of which are concerned with living things, but 

 the origin of species has a peculiar interest to the 

 biologist. This particular problem still offers prom- 

 ise of solution on a basis of established scientific 

 principles, and even though a fragment of the 

 whole subject, it is a fragment of the utmost im- 

 portance. Its solution would, if nothing else, re- 

 lease a vast amount of energy for the pursuit of 

 other scientific inquiries ! 



The scientific world has been thoroughly inter- 

 ested in problems of organic evolution for approxi- 

 mately three-quarters of a century. During that 



* Conger, G. P., New Views of Evolution, p. 77, 1929. 



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