A 

 TEXTBOOK OF BOTANY 



FOR 



COLLEGES AND UNIVERSITIES 



BT MEMBERS OF THE BOTANICAL STAFF OF THE 

 UNll^ERSITT OF CHICAGO 



JOHN MERLE COULTER, Ph.D. 



PROFESSOR OF PLANT MORPHOLOGY 



CHARLES REID BARNES, Ph.D. 



LATE PROFESSOR OF PLANT PHYSIOLOGY 



HENRY CHANDLER COWLES, Ph.D. 



ASSOCIATE PROFESSOR OF PLANT ECOLOGY 



VOL. II. ECOLOGY 



NEW YORK ■:• CINCINNATI •:• CHICAGO 



AMERICAN BOOK COMPANY 



