CHAPTER I 



RECENT DEVELOPMENTS IN HEREDITY AND 

 EVOLUTION: GENERAL INTRODUCTION 



This series of lectures is intended to present, in outline, 

 the recent development of knowledge in reference to heredity 

 and evolution. These subjects have to do, not only with 

 the most fundamental conceptions of biology, but they have 

 come to be of immense practical importance in animal and 

 plant breeding. From every aspect, therefore, they appeal 

 to all persons intelligent enough to be interested in the 

 progress of knowledge and in human welfare. At the same 

 time, it is recognized that most people are denied the oppor- 

 tunity of knowing the progress that has been made in these 

 subjects, through lack of biological training or lack of time. 

 To them the suggestions of progress have come chiefly 

 through ephemeral and often misleading publications. 



It is the purpose of this series, therefore, to present this 

 information in such a form that it can be appreciated by 

 those who have no special training in biological work ; in short, 

 to interpret the significant results of recent investigations. 



Before presenting the recent developments in the inves- 

 tigation of heredity and evolution, it is essential to provide 

 a historical background, for nothing is more obvious than 

 that the work of today has evolved gradually from all the 

 work of the past. It should be understood, also, that the 

 subject is so vast in scope and in work that to outhne it in 

 a few lectures will require the most rigid selection of material, 

 a selection so rigid that students of the subject will be able 

 to point out glaring omissions. 



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