Vlii PREFACE 



separately and from the individual plant standpoint, 

 as to their origin, characters, classification, varieties, 

 selection, and hybridization. Thereafter these cereals 

 are treated together in respect to the further subjects 

 of soil and climatic relations, acclimatization, cultiva- 

 tion, irrigation, weeds, insect and fungus pests, and 

 uses. By this method there is avoided much duplica- 

 tion of topics under each cereal that would otherwise 

 be necessary. For example, smut diseases are discussed 

 for all the cereals at the same time, and not duplicated 

 under each cereal. Buckwheat, being botanically dif- 

 ferent from the four cereals referred to, is treated 

 separately as to all topics ; and the same is true of rice. 



Scientific names, references to literature, and the 

 matter in small print, are included for scientific ac- 

 curacy and completeness, and may be omitted to such 

 an extent as may seem desirable to the instructor. 

 Citations of literature are made in the body of the 

 text, and refer to a bibliographic list in the appendix, 

 arranged (1) according to chapters, (2) alphabetically 

 as to authors under the chapters, and (3) chronolog- 

 ically under each author. It should be noted that the 

 classification under each cereal is tentative, and is pre- 

 sented as a temporary working basis for the student. 

 The subject is an open field of investigation in which 

 little has been done. 



As this is the author's first book, and it is attempted 

 to present our knowledge of the cereals up to date, 

 there may naturally be errors therein. Any informa- 

 tion as to such shortcomings will be gratefully received. 



Acknowledgment is hereby made of much assistance 

 received from many persons in the preparation of the 

 book, particularly from members of the Office of Cereal 

 Investigations and others in the Federal Department 



