THE 
BOTANICAL GAZETTE 
December ro9xr 
Editor: JOHN M. COULTER 
CONTENTS 
Light Intensity and Transpiration Burton Edward Livingston 
The Embryo Sac of Epipactis 
William H. Brown and Lester W. ee 
The Oxygen Minimum and the Germination of Xanthium 
Seeds Charles Albert Shull 
Briefer Articles 
A Protocorm of Ophioglossum W. J. G; Land 
Current Literature 
The ‘University of Chicago Press 
be geaiae ay ILLINOIS 
_ THE CAMBRIDGE UNIVERSITY PRESS, London and Edipbursh 
WILLIAM WESLEY & SON, L ondon 
oe: "TH, STAUFFER, Leipzig 
THE -MARUZEN- KABUSHIKI-KAISHA, peat ae Osaka, Kote 
