A Taxonomic Study of the Genus Eugenia 
(Myrtaceae) in Hawaii 1 
Kenneth A. Wilson 2 
The pantropic genus Eugenia (Myrtaceae) 
is represented in the forests of Hawaii by 
several species. A recent taxonomic treatment 
of the genus by Merrill and Perry (1939) 
divided the greater number of species of 
Eugenia into the genera Syzygium and Eugenia 
sensu strictu. A later study by Henderson 
(1947), based on the Malayan species, re- 
jected this classification. 
According to the Merrill and Perry classi- 
fication, both Syzygium and Eugenia sensu 
strictu are present in the Hawaiian flora. There- 
fore, it seemed that an evaluation of the re- 
cent generic treatments based on these 
representatives would be of value. My study 
of the generic status of Eugenia and Syzygium 
led to the question of the specific status of the 
indigenous Hawaiian members. As a result 
of my investigations I have rejected the trans- 
fer of species of Eugenia to Syzygium , de- 
scribed a new species from the island of Molo- 
kai, and reduced two species and one variety 
to synonomy. 
ACKNOWLEDGMENTS 
Prof. Harold St.John suggested to me that 
the problem of the generic status of Eugenia 
was in need of further study. I have under- 
1 Part of a thesis submitted to the Graduate School 
of the University of Hawaii in partial fulfillment of the 
requirements for the degree of Master of Science. 
2 Department of Botany, University of Michigan, 
Ann Arbor, Michigan. Manuscript received February 
10 , 1956 . 
taken this problem under his guidance and 
am indebted to him for his help and en- 
couragement. I wish to thank Miss Marie C. 
Neal, Curator of the Herbarium of the Bernice 
P. Bishop Museum, for her helpful and valu- 
able assistance and for the opportunity to 
work on the specimens in the herbarium. Dr. 
Rogers McVaugh, Curator of Phanerogams 
of the Herbarium of the University of Michi- 
gan, has generously made the space and 
facilities of the herbarium available to me for 
continuing this study. I gratefully acknowl- 
edge the assistance of Dr. Joseph F. Rock, 
who provided valuable information based on 
his knowledge and experience with the Ha- 
waiian flora. 
I am indebted to the following herbaria for 
the loan of herbarium specimens, photo- 
graphs of types, and other valuable materials: 
Herbarium of Bernice P. Bishop Museum, 
Gray Herbarium, Herbarium of the Royal 
Botanical Gardens at Kew, Botanische Staats- 
sammlung Miinchen, Herbarium of the Uni- 
versity of Michigan, Herbarium of the New 
York Botanical Gardens, and United States 
National Herbarium. 
HISTORY OF THE GENUS 
Since Linnaeus’ treatment of Eugenia in 
Species Plantarum (1753: 470), more than 800 
species have been described or transferred to 
this genus. Many botanists have been dis- 
satisfied with the wide range of difference in 
form shown by the members of the genus. 
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