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CONTRIBUTIONS FROM THE GRAY HERBARIUM OF HARVARD 
UNIVERSITY,— NEW SERIES, NO. LX. 
I. ON TROPICAL AMERICAN COMPOSITAE, CHIEFLY 
EUPATORIEAE. 
By B. L. Rosrnson. 
Fresented June 26, 1919. Received June 26, 1919. 
DurinG the past year the writer has continued his studies on the 
South American members of the genus Eupatorium, giving particular 
attention to those of Peru and Bolivia. Of the Peruvian it has proved 
possible to complete a recension, which, by bringing together widely 
scattered data, placing on record-a considerable number of new species, 
and furnishing specific keys in each section, will, it is hoped, render a 
knowledge of these plants much more readily accessible and con- 
siderably facilitate their precise identification. 
There have been several sources of new information regarding 
tropical American Eupatoritims and many facts have been observed 
which were not available during the preparation of the writer’s revision 
of the Colombian, Venezuelan, and Ecuadorian species, a treatment 
completed about a year ago (Proc. Am. Acad. liv. 235-367, 1918). 
Thus, for instance, the later portions of Dr. F. W. Pennell’s extensive 
collections from Colombia proved to contain interesting Eupatorium 
material to an unsuspected extent, including several additional 
novelties. A small Colombian collection, prepared by Bro. Ariste- 
Joseph and received at the Gray Herbarium in continuation of ex- 
change from the United States National Herbarium, has yielded 
still another new species from the vicinity of Bogoté, a region already 
exceptionally rich in its representatives of the genus. A somewhat 
extended collection of the flora of Caracas and adjacent portions 
of northern Venezuela has been obtained from Prof. H. Pittier. This 
has given considerable supplementary information regarding the 
Eupatoriums of the regions explored. Finally, the expedition of 
Dr. J. N. Rose to Ecuador has brought in the most notable single 
collection as yet received from that country, including a suite of some 
twenty-eight different Eupatoriums, among which at least four merit 

