Vol. XXI, No. 1 
22 March, 1922 
THE 
NEW PHYTOLOGIST 
A BRITISH BOTANICAL JOURNAL 
EDITED BY 
A. G. TANSLEY, M.A., F.R.S. 
UNIVERSITY LECTURER IN BOTANY 
CAMBRIDGE 
IN CONSULTATION WITH THE 
THE CAMBRIDGE BOTANY 
CONTENTS 
PAGE 
Permeability continued. By Walter Stiles. Chapter VI. Osmotic Pressure i 
A Study of some of the Factors Controlling the Periodicity of Freshwater 
Algae in Nature. By William J. Hodgetts, M.Sc. (With 2 figures 
in the text) Concluded .15 
Studies in Phaenology, No. 3, 1921. By Francis Darwin . . . 34 
Further Observations upon the Mechanism of Root Pressure. By J. H. 
Priestley.41 
Records of Autumnal or Second Flowerings of Plants. By Francis Darwin 
and A. Shrubbs (University Herbarium, Cambridge) ... 48 
>0.542 
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