The catalogue reflects our taxonomic opinions as expressed in 
our choices of literature to cite. Because systematics is a dynamic 
discipline, with new data and revisions constantly published, the 
nomenclature appearing in the new edition of Steyermark’s Flora of 
Missouri will almost certainly differ for some groups from the 
nomenclature followed here. We view this as healthy refinement 
rather than as additional confusion. It is the fact that new taxa an 
new names are continually forced to the attention of Missouri's 
botanists that has created the demand for a newly revised floristic 
manual. With this in mind, we urge interested parties to bring 
further new botanical finds from Missouri to our attention and to 
provide constructive criticism of the taxonomic views presented here. 
ACKNOWLEDGMENTS 
We have enjoyed the generous support and assistance of many 
outstanding individuals during the process of compiling this catalogue. 
Although the authors ultimately must take full responsibility for the 
contents, a number of people provided advice and information that 
we feel greatly improved the volume. Peter Raven, Gerrit Davidse, 
and Nancy Morin at the Missouri Botanical Garden, as well as James 
H. Wilson, Rick Thom, Virginia Wallace, and John Wiley (retired) 
of the Missouri Department of Conservation, share responsibility for 
the inception of the Flora of Missouri Project, and have 
herbaria consulted have always been helpful with oe pertinent 
specimens and providing general information. The s at the 
wonderful Missouri Botanical Garden library, especially Dale Johnson, 
were indispensable in locating esoteric items of literature and in 
suggesting references. Amy Scheuler and George Rogers provided 
editorial expertise and Debbie Kama tamed our often temperamental 
computers. A number of individuals reviewed portions of the 
catalogue and provided taxonomic assistance with ore problems: 
Ihsan Al-Shehbaz (Brassicaceae), Richard Carte Cyperus 
Eleocharis), David Castaner (Carex), William D’Arcy Bi ea, 
Roy Gereau (Poaceae), Peter Hoch (Onagraceae), Duane Isely 
(legume families), Richard Jensen (Fagaceae), Robbin Moran (ferns 
and fern allies), James Phipps (Crataegus), Richard Rabeler 
(Caryophyllaceae), Anton Reznicek (Carex). We are especially 
indebted to Robert Kral and Floyd Swink for their thorough review 
of the entire manuscript, and to Doug Ladd, among other things, for 
his insightful examination of introduced species. In addition, a 
number of Missouri botanists contributed advice and information to 
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