vi PREFACE 



series of lecture-notes which was used in connection with a course 

 in " Phyto-chemistry " which was offered for several years to 

 the students of the Plant Science Group of the 'University of 

 Minnesota. In the preparation of these notes, extensive use was 

 made of the material presented in such general reference works as 

 Abderhalden's " Biochemische Handlexicon" and "Handbuch 

 der Biochemischen Arbeitsmethoden," Oppenheimer's "Hand- 

 buch der Biochemie des Menschen und der Tiere," Czapek's 

 "Biochemie der Pflanzen," Rohmann's "Biochemie/' Frankel's 

 "Descriptive Biochemie," and "Dynamische Biochemie," Euler's 

 "Pflanzenchemie," and Haas and Hill's "Chemistry of Plant 

 Products"; as well as of the most excellent series of "Monographs 

 on Biochemistry," edited by Plimmer, several numbers of which 

 appeared in print prior to and during the period covered by the 

 preparation of these lectures. Frequent use was made also of 

 the many special treatises on individual groups of compounds 

 which are mentioned in the lists of references appended to each 

 chapter, as well as of articles which appeared from time to time in 

 various scientific journals. 



Hence, no claim is made of originality for the statements 

 presented herein, except in an insignificant number of studies 

 of enzyme action, and of the possible physiological functions of 

 certain specific compounds. The only contributions which the 

 writer has felt qualified to make to this general subject are those 

 of an intense personal interest in the chemistry of plant processes 

 and a viewpoint with reference to the relation of chemical processes 

 to vital phenomena which will be apparent as the various subjects 

 are presented. 



The text has been prepared upon the assumption that the stu- 

 dents who will use it will have had some previous training in ele- 

 mentary inorganic and organic chemistry. A systematic labora- 

 tory course in organic preparations, such as is required of students 

 who are preparing to become professional chemists, is not at all a 

 necessary requisite to the understanding of the chemistry of the 

 different groups of plant compounds as here presented; but it is 

 assumed that the student will have had such previous training as 

 is now commonly given in a one-year collegiate course in "Gen- 

 eral Chemistry," or a year's work in general inorganic chemistry 

 followed by a brief course in "Types of Carbon Compounds" or 

 "Elements of Organic Chemistry," such as is usually required of 



