to the state; probably no other state east of the Mississippi
has more than 1 or 2% endemism. And finally, many species
may be explained as chance or intentional introductions associ-
ated with the activities of man.
 A considerable number of species customarily reported to
range into Florida have been excluded from this Checklist. For
many of these no supporting specimen could be located, for
others the only record is an early collection with imprecise
(often only "Florida") and possibly erroneous data. As a gen-
eral rule, if a name is included in this list, a specimen of that
species from the state has either been seen by the writer or is
cited by a monographer of the appropriate genus. Other pub-
lished statements have been used solely as aids to further
search. In case of doubt, the consistent practice has been to
exclude a species that might possibly be in Florida, rather than
to include one that possibly is not.
 This Checklist records 1183 species in 318 genera. Insofar
as this listing can serve as an indication, the entire vascular
flora of the state of Florida exceeds in number that of any other
state in the eastern United States and is perhaps surpassed in
this country only by the floras of California and Texas. On a
comparative basis (i. e., dicots excluded), using as examples
some states of roughly equal area in which the flora is well
known, Indiana contains 705 species, Missouri has 715 species,
and the diversified topography of North and South Carolina
supports 1033 species.
 South of Florida, floras are consistently larger in tropical
areas of equivalent size. The conifers and monocots of Cuba
total 1303 species. (Data on number of ferns and "fern allies"
are unavailable; a comparative figure for Florida, excluding
these groups, is 1058.) A compilation for Costa Rica, reflecting
a wealth of orchids and other tropical forms, gives 1955 species
of conifers and monocots.
 Scientific Names
 Each species recognized in this Checklist is denoted by a
scientific name. When given in full, a scientific name consists
of three parts a genus, a species, and an author. Such names
are intended, by international agreement, to serve as a univer-
sally recognizable indicator of the species to which they are
applied, thus permitting precise understanding of the plant
under discussion regardless of language or nationality.
 The genus and the species of a plant are either in Latin or
are treated as Latin. The author is an indication, usually ab-