CHECKLIST OF THE VASCULAR FLORA OF FLORIDA

 PART I.

 Psilopsida, Lycopsida, Sphenopsida, Filicinae,
 Gymnospermae, Monocotyledoneae.
 Daniel B. Ward I

 INTRODUCTION
 This Checklist records the names of those species of vascu-
lar plants found native or naturalized in the state of Florida.
Part I, published here, includes the ferns and other non-seed-
bearing plants, the cone-bearing species, and that portion of
the flowering plants known as the monocotyledons; Parts II
and III will contain the larger portion of the flowering plants,
the dicotyledons. The non-vascular plants, those species with-
out specialized conducting tissues, will not be included.
 The information given in this Checklist is restricted to the
minimum necessary to encompass the nomenclaturally correct
names of the included species, with sufficient synonymy to as-
sociate these names with those used by the most comprehen-
sive author on the southeastern flora, J. K. Small. Common
names are also provided, where such names are available and
when they are believed to be in current use. No infraspecific
taxa subspecies, varieties, or forms are recorded in this
list, although in many cases the existence of such lesser cate-
gories is apparent in both the field and the herbarium.

 Origin and Number of Species
 The flora of Florida is formed of several components, re-
flecting the area of origin of the individual s p ecie s. The
largest component, perhaps as much as half of the entire flora,
is of North American derivation and contains the species
familiar on the Coastal Plain of the southeastern United States
that reach their southernmost limit in Florida. A large group
of species in the state is clearly of tropical origin, with rep-
resentatives occurring in the eastern United States only in
southern Florida; among these species lie many of the more
difficult taxonomic problems. Approximately 10%o of the species
in Florida are endemics, that is, species restricted in their range

 1 Associate Professor and Associate Botanist, Department of Botany,
 Agricultural Experiment Station, University of Florida, Gainesville.