8 MR. G. BENTHAM’S SYNOPSIS OF DALBERGIE.E, 
carpus form, which prevails in America, is the orily one in Africa, and 
is scarcely represented in Asia by Pongamia glabra. Dalbergia, with 
sixty-nine species, has thirty-seven Asiatic species, ten African (of 
which two are also in America), and twenty-four American species, 
the different groups not affecting any particular geographical area. 
Pterocarpus, with fifteen species, has three Asiatic, five African, and 
seven American species, those only with stipitate pods found in Asia, 
the sessile-podded prevailing in America, and the two forms distri- 
buted in Africa. Of the remaining genera, the two largest, Mache- 
rium with sixty-four species, and Geoffroya (including Andira), 
with nineteen species, are American, with two species of the former 
and one of the latter extending also into Africa. Seven more are 
exclusively American, viz., Platymiscium with thirteen species, Di- 
pteryx with twelve, Cyclolobiumn with four, Tipuana, Centrolobium, 
and Pecilanthe with three each, and Platypodium with only two. 
There remain three isolated species, of which Euchresta is Asiatic, 
Ostryocarpus African, and Hymenolobium American. Among the 
doubtful Dalbergiee known to me, which do not appear referable 
to any of the described genera, but which, from the imperfection of 
the specimens, I am unable to determine, there are—one Asiatie, 
two African, and two American species. 
Considering now the classification of Dalbergiea, it will be found 
that the 286 species here described have (in so far as previously 
known) been distributed by various authors into above forty 
genera, now reduced to twenty-three, which appear to be tolerably 
well defined, although, to make them really natural, it would have 
required to cut them down, as above mentioned, to fifteen. It is 
not, however, so easy to determine the linear or relative arrange- 
ment of these genera. The best which has suggested itself to me 
is their distribution into three groups: the Pterocarpee, with dry 
fruits and the leaflets mostly alternate along the petiole; the 
Lonchocarpee, with dry fruits and the leaflets more strictly oppo- 
site; and the Geoffroyee, with a fruit usually drupaceous, and 3 
single pendulous seed. The first of these, the Pterocarpee, may 
be considered as the more genuine representatives of the tribe ; 
the fruit is always strictly indehiscent, usually hardened round the 
seed, which exactly fills the cavity it occupies, and almost always 
samaroid, that is, attenuated above or below the seed, or both, or 
all round, into a thin edge or wing. In the flower, it may be ob- 
served that the vexillum is never appendiculate or callous at the 
base, the wings are always free from the keel, the keel-petals are 
usually, but not quite always, shortly united at the outer edge; 
