Vol. IX. JULY, 1922 No. 7 
AMERICAN 
JOURNAL OF BOTANY 
OFFICIAL PUBLICATION OF THE 
BOTANICAL SOCIETY OF AMERICA 
CONTENTS 
A preliminary study of Claviceps purpurea in culture . .... . . . . . . Walter W. Bonns 339 
Studies in the genus Gymnosporangium IV, Distribution of the mycelium and the subcuticular 
origin of the telium in G. clavipes ^ ....... . . B. O. Dodge 354 
Certain relations between root development and tillering in wheat : significance in the produc- 
tion of high-protein wheat . . W, F. Gericke 366 
Tl« pollination of Marcgravia : a classical case of oruithophily ? . . . . . . Irving W. Bailey 370 
EflTironmental temperatures of fungi in nature, ............. Neil E. Stevens 385 
The reduction divisions in the pollen mother cells of Oenothera p^t,pw ^\ rTvi Axir. ^gi 
''^%L^^ ^^^^ 
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