Vol. XXXIII. No. CXXXI. July, 1919. Price 14s. 
Annals of Botany 
EDITED BY 
DUKINFIELD HENRY SCOTT, M.A., LL.D, D.Sc., F.R.S. 
LATELY HONORARY KEEPER OF THE J-O OR ELL LABORATORY, ROYAL BOTANIC GARDENS, KEW 
JOHN BRETLAND FARMER, D.Sc., M.A., F.RS. 
PROFESSOR OF BOTANY, ROYAL COLLEGE OF SCIENCE, LONDON 
FRANCIS WALL OLIVER, M.A., D.Sc., F.R.S. 
QUAIN PROFESSOR OF BOTANY, UNIVERSITY COLLEGE, LONDON 
AND 
ROLAND THAXTER, M.A., Ph.D. 
PROFESSOR OF CRYPTOGAM 1C BOTANY IN HARVARD UNIVERSITY, CAMBRIDGE, MASS., U.S.A. 
ASSISTED BY OTHER 
LONDON 
HUMPHREY MILFORD, OXFORD UNIVERSITY PRESS 
AMEN CORNER, E.C. 
Edinburgh, Glasgow, New York, Toronto 
Melbourne, Cape Town, and Bombay 
I 9 I 9 
Printed in England at the Oxford University Press. 
