99 
AMERICAN 
JOURNAL OF BOTANY 
OFFICIAL PUBLICATION OF THE 
BOTANICAL SOCIETY OF AMERICA 
EDITORIAL COMMITTEE 
C. E. Allen, Editor-in-Chief 
University of Wisconsin ^ 
William Crocker, L. R. Jones, 
University of Chicago University of Wisconsifi 
C. Stuart Gager, Business Manager Arthur H. Graves, 
Brooklyn Botanic Garden Brooklyn Botanic Garden 
R. A. Harper, Jacob R. Schramm, 
Columbia University Cornell University 
C. L. Shear, Bureau of Plant Industry 
(Representing American Phytopathological Society) 
VOLUME VIII1921 
WITH TWENTY-SIX PLATES AND NINETY-FIVE TEXT FIGURES 
PUBLISHED 
IN COOPERATION WITH THE BOTANICAL SOCIETY O 
BY THE 
BROOKLYN BOTANIC GARDEN 
At 41 North Queen Street, Lancaster. Pa, 
