Vol. VIII. JUNE, 192 1 . No. 6 
AMERICAN 
JOURNAL OF BOTANY 
OFFICIAL PUBLICATION OF THE 
BOTANICAL SOCIETY OF AMERICA 
CONTENTS 
specialization and fundamentals in botany . . . . Joseph Charles Arthur 275 
Certain aspects of the problem of physiological correlation . .CM. Child 286 
Water deficit and the action of vitamines, amino-compounds, and salts on 
hydration D. T. MagDougal 296 
The eusporangiate ferns and the stelar theory . . . . , . D. H. Campbell 303 
The relation of plant patholbgy to human welfare .... . . F.L.Stevens 315 
PUBLISHED 
IN COOPERATION WITH THE BOTANICAL SOCIETY OF AlilERICA 
BY THE 
BROOKLYN BOTANIC GARDEN 
At 41 North Queen Street, Lancaster, Pa. 
Eutered as second-class matter February 21, 1914, at the post office at Lancaster, Pennsylvania, 
under the act of March 3, 1879 
