NATIONAL ACADEMY OF SCIENCES. 



Volume X. 



SIXTH MEMOIR. 



COMMEL1NA0E.E. 



MORPHOLOGICAL AND ANATOMICAL STUDIES OF THE VEGETATIVE 



ORGANS OF SOME NORTH AND CENTRAL 



AMERICAN SPECIES. 



BY 

 THEODORE HOLM. 



PRESENTED TO THE ACADEMY BY GEORGE I_. GOODALE. 



157 



