BOTANICAL MUSEUM LEAFLETS 
HARVARD UNIVERSITY 
CampripGr, Massacuusetrts, December 12, 1975 VoL. 24, No. 7 
STUDIES IN THE GENUS ONCIDIUM. IL. 
BY 
Joun E. Stacy* 
The genus Oncidium, one of the largest orchid genera 
in the New World, has been of continuous intrigue to 
both botanists and horticulturists. Although during the 
past 175 years several attempts have been made to clarify 
the various species that comprise this genus, no satis- 
factory compendium is presently at hand. It was Lind- 
ley who first produced a kind of monograph, or rather a 
revision of the genus in 1841, in his Sertum Orchidaceum 
under t. 48 with 101 species, and an expanded version 
of it in 1855 in his Folia Orchidacea with 198 species. 
These treatments were in use almost uninterruptedly 
until 1922 when anew attempt was made by Kraenzlin. 
It is unfortunate that the Kraenzlinian version was any- 
thing but an improvement on the former treatments. 
Since that time two synopses have appeared, one in 1970 
by Garay (Taxon 19: 443-467, 1970), and the other 
jointly by Garay and me in 1974 (Bradea 1(40): 893- 
424, 1974). IL believe that in this latter synopsis we have 
clearly outlined the infrageneric divisions which I intend 
to follow section by section in this series. These papers 
will not follow the sequence outlined in the key to the 
sections, but rather will treat them randomly depending 
on the demand and need of immediate attention. Conse- 
* Research Fellow, Orchid Herbarium of Oakes Ames. 
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