CONTENTS. 



Page. 



I. Introduction ... ... ... ... ... 1 



II. The methods employed in raising the experimental plants ... ,5 



III. Pollination and natural cross-fertilization ... ... 9 



1. Pollination ... ... ... ... 9 



2. Natural cross-fertilization ... ... ... H 



3. The production of self-fertilized seed ... ... 12 



IV. Classification and description of the tj'pes ... ... 14 



1. Morphological characters ... ... ... n 



(a) Habit ... ... ... ... U 



(b) Leaves ... ... ... ... 15 



(c) Inflorescence ... ... ... 15 



(d) Flowers ... ... ... ... 15 



2. Scheme of classification ... ... ... 18 



3. Description of the types ... ... ... 19 



