Vol. VIII. 
DECEMBER, 192 1 
No. 10 
AMERICAN 
JOURNAL OF BOTANY 
OFFICIAL PUBLICATION OF THE 
BOTANICAL SOCIETY OF AMERICA 
CONTENTS 
Pollen and pollen enzymes . Julia Bayles Paton 471 
The embryogeny of Cyrtanthus parvifl6rus Baker . . Wm. Randolph Taylor 502 
Studies on plant cancers III. The nature of the soil as a determining factor in 
the health of the beet, Beta vulgaris, and its relation to the size and 
weight of the crown gall produced by inoculation with Bacterium tume- 
faciens . 
Index to Volume VIII ...... 
PUBLISHED 
IN COOPERATION WITH THE BOTANICAL SOCIETY OF AMERICA 
BY THE 
BROOKLYN BOTANIC GARDEN 
At 41 North Queen Street, Lancaster, Pa. 
Entared as secoad-class ra^lt«r Februarr 21, 1914, at th« post office at Lancaster, Pennsylvania, 
under the act of March 3, 1879 
