Oct., 192 1 ] EECHTEL FLORAL ANATOMY OF URTICALES 
407 
4. The Urticales are probably not far removed from primitive ento- 
mophilous ancestors. 
5. Floral anatomy emphasizes the idea that the Urticales are a natural 
order which is made up of three natural families as classified by Engler. 
6. The natural position of the Ulmaceae, Moraceae, and Urticaceae is 
at the culmination of a distinct line of descent from a protoangiospermous 
plexus from which also the Ranalian line descended. 
The writer wishes to express his gratitude to Dr. A. J. Eames, to whom 
he is indebted for this problem as well as for advice and assistance while the 
work was in progress. 
Department of Botany, 
College of Agriculture, 
Cornell University, 
Ithaca, N. Y. 
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