CONTENTS 



CHAPTER I 



FACE 



The Problem i 



CHAPTER H 

 Historical 8 



CHAPTER III 

 Mendel's Work 17 



CHAPTER IV 

 The Presence and Absence Theory .... 29 



CHAPTER V 

 Interaction of Factors 42 



CHAPTER VI 

 Reversion 59 



CHAPTER VII 



Dominance 68 



is 



