ILLUSTRATIONS 



FIGURES IN TEXT 



1. Scheme of Inheritance in simple Mendelian Case 



2. Feathers of Silky and Common Fowl . 



3. Single and Double Primulas 



4. Fowls' Combs ...... 



5. Diagram of Inheritance of Fowls' Combs 



6. Fowls' Combs ...... 



7. Diagram of Fg Generation resulting from Cross 



between two White Sweet-Peas 



8. Diagram illustrating 9:3:4 Ratio in Mice . 



9. Sections of Primulas ..... 



xiii 



19 



27 

 28 

 30 

 34 

 36 



43 

 48 



51 



