PREFACE xi 



186, 190, 191, 193, 209, 211, and 213; Mori Uyehara for Figs. 

 154 and 155; E. J. Slanetz for Fig. 18, and A. I. Weinstein for 

 Figs. 137 and 143, as well as for Figs. Ill and 230 from his 

 unpublished work. The other original drawings, some ninety in 

 all, are by the author. He is indebted to Professor W. F. Ganong 

 and the Macmillan Co. for the use of four figures from "A 

 Textbook of Botany for Colleges"; to Professor W. F. Ganong 

 and Henry Holt and Co. for the use of two figures from "The 

 Living Plant", and to Dr. C. S. Gager and P. Blakiston's Sons 

 and Co. for the use of four figures from "The Fundamentals of 

 Botany". To the United States Forest Service, the United 

 States Forest Products Laboratory, the Desert Laboratory of the 

 Carnegie Institution, the Brooklyn Botanic Garden, the editors 

 of the Journal of Heredity and of Genetics, Dr. A. J. Grout, 

 Professors E. B. Babcock and R. E. Clausen, Dr. M. A. Howe, 

 Professor L W. Bailey, Professor E. W. Berry, Professor M. L. 

 Fernald, and Professor G. S. Torrey the author is indebted for 

 original illustrations or permission to use published ones. A 

 few familiar figures have also been taken from some of the older 

 texts. 



The author will be very glad to welcome criticisms and sugges- 

 tions, particularly those which relate to the employment of the 

 Questions and Problems in the conduct of class work. 



E. W. SiNNOTT. 

 Connecticut Agricultural College, 

 July, 1923. 



