The present paper is a revision of the taxonomy of the genus Sophora Linn. of
the world. The history of the taxonomy of this genus is reviewed, and the morpholo-
gical characters of those genera, in dispute in the past, such as Edwardsia and the
Goebelia now incorporated into the genus Sophora are discussed. Opinions on some
species to be included in this genus together with the previous taxonomical systems are
evaluated. The morphological characters of various organs of the plants in this genus
are critically analyzed in detail and their taxonomic significance is assessed. The author
considers that the characters of the legume structure and their modes of dehiscence
are of primary significance in the taxonomy and phylogeny of this genus. The new
taxonomic system of the genus Sophora Linn. proposed by the author is based chiefly
on the characters of legume structure, their different modes of dehiscence and other
morphological characters. The proposed system divides the genus Sophora Linn. into
two subgenera, seven sections and nineteen series.
Subgenus Sophora. Legume consists of three layers of imcomplete pericarp (meso-
carp degenerated into two narrow strips), different modes of dehiscence on maturity,
and flowers ebractiolate. According to the different modes of dehiscence of legume, the
subgenus is subdivided into three sections. Section Disamaea Lindl. Mature legume de-
hiscing typically into two valves. This section consists of two series and five species.
Section Pseudosophora DC. Legume dehisced into two valves along two sutures with
apparent torn lines on the surfaces of two valves. This section includes three series
and six species. Section Sophora. Legume has a part of the epicarp (including me-
socarp and the two sutures) dehiscing along the torn linesk and the endocarp (includ-
ing a part of the epicarp) dehiscing along two sutures, thus spliting cross wise into four
valves. This section includes nine series, thirty one species, twelve varieties, and one
forma.
Subgenus Styphnolobium (Schott) Tsoong. Legume consists three complete layers
of fleshy or woody pericarp, indehiscing upon maturity, and flowers frequently. Accord-
ing to the nature of the various layers of pericarp, this subgenus is subdivided into
following sections:Section Raphanocarpus Tsoong. Epicarp is membranous, mesocarp
has apparent nerved reticulation, endocarp fleshy, and seeds overlapping. This section
has one serices and one species only. Section Arizoniatae Tsoong. Legume is slightly
distorted, epicarp membranous, mesocarp fleshy, and endocarp elastic. This section has
only one series, two species and one variety. Section Agastianus (Rafin.) Tsoong.
Legume epicarp and mesocarp apparently lignified, and endocarp is nearly membranous.
This section has only one series and one species. Section Styphnolobium (Schott)
Tsoong. Legume epicarp is membranous, mesocarp and endocarp are fleshy, and leaflets
with subulate stipel. This section includes two series, two species, four varieties and
five formae.
Keys to the taxonomical system and species in each series are given. In these keys
are included all the species observed by the author, their taxonomical positions can be
inferred by descriptions. Species of uncertain taxonomical positions are duely discuss-
ed and opinions as to their proper treatment are expressed. A few species, with their
specimens unavailable to the author and their taxonomical positions cannot be inferred
as judged by the original records, are temporarily put aside at the end of the paper
as species of unknown systematical position, until their type specimens are examined
in the future or decisions are made by other taxonomists.
