s 



CONTENTS. 



PAGE 



I. Origin and Histoky 



A. Origin 



B. History 



C. List of References " 



OK 



D. Historical Summary 



E. List of Synonyms "' 



33 

 II. Economic Importance 



A. Distribution and Comparative Yield ^^ 



B. The Sweet Potato as a Starch Producer 36 



C. The Sweet Potato as a Sugar Producer 45 



III. The Structure of Ipom(EA Batatas 



A. Root ^^ 



B. Stem "^^ 



C. Leaf ^^ 



57 



IV. Classification of Varieties 



A. Popular Varieties •. 



B. The System of Classification ^^ 



C. Key to Varieties '^^ 



D. Alphabetical List of Formulas ^^ 



E. Alphabetical List of Varieties 82 



85 



F. Descriptions 



V. List of Illustrations 



