viii GENERAL BOTANY 



botany. The second relates to the increasing importance of first- 

 hand knowledge of the cell and mitosis to a proper understand- 

 ing of the modern literature and popular discussions concerning 

 genetics, heredity, and breeding. This part of biology is also of 

 fundamental importance in psychology, physiology, and sociology. 

 In case teachers do not care to give much time to laboratory work 

 on mitosis, the outline and figures of the text should furnish a 

 valuable basis for class discussion of this important topic. 



The presentation of plant structure from the viewpoint of 

 modern anatomy is also new in an elementary textbook, but 

 such treatment is justified by the author's experience in teach- 

 ing this aspect of the subject to beginning students in botany. 

 It is hoped also that the outline figures and the simple treat- 

 ment in the text will enable instructors not familiar with this 

 phase of botany to present the subject from the standpoint of 

 modern plant anatomy. 



The laboratory directions, which are printed under separate 

 cover, are intended to stimulate interest and observation without 

 giving detailed guidance in laboratory work. 



Acknowledgments. In closing the author desires to acknowl- 

 edge his indebtedness to former students and assistants, as well 

 as to other botanists and friends, who have materially aided him 

 in the completion of this book. 



First acknowledgements are due to Miss M. Louise Sawyer, 

 instructor in botany at Knox College and a former student and 

 instructor at Beloit College. Miss Sawyer's criticisms and sug- 

 gestions were invaluable in the early stages of writing the text 

 and while it was being tested with classes in Beloit College. 

 In the making and reproduction of the original drawings Miss 

 Sawyer deserves equal credit with the author for whatever of 

 originality or helpfulness they may be found to possess. She 

 reproduced all of the original drawings in ink and made the 

 camera drawings on the cell, mitosis, and anatomy from slides 

 in the author's laboratory. The drawings on the pollen tubes 

 and sperm atogenesis in Iris are taken from an original paper 

 published by Miss Sawyer. 



