Vol. VIII. APRIL, 1921 No. 4 
AMERICAN 
JOURNAL OF BOTANY 
OFFICIAL PUBLICATION OF TH|;^----~— -.^ 
BOTANICAL SOCIETY OF AMERICA % 
MAY - 01921 ^ 
CONTENTS 
The morphology and anatomy of Rhus diversiloba . . . .James B. McNair 179 
Distribution of the Malvaceae in southern and western Texas 
Herbert C. Hanson 192 
Note on the histology of grain roots . Grace A. Dunn 207 
North American pipers of the section Ottonia William Trelease 212 
Monocarpy and pseudomonocarpy in the Cycadeoids . ... G. R. Wieland 218 
PUBLISHED 
IN COOPERATION WITH THE BOTANICAL SOCIETY OF AMERICA 
BY THE 
BROOKLYN BOTANIC GARDEN 
At 41 North Queen Street, Lancaster, Pa, 
Entered ms ••cond-clats matter February 21, 1914, at the post office at Lancaster, Pennsylvania, 
under the act of March 3, 1(79 , 
