198 NATURAL HISTORY OF PLANTS. 
or subsessile pluriovulate ovary,’ tapering above into a style which 
is lodged in the keel, and is similarly twisted. The surface of the 
style is often covered with hairs for a considerable distance, and its 
apex is dilated into a more or less oblique stigmatiferous head 
(fig. 151). The fruit is a straight or bowed pod, subcylindrical or 
compressed ; the pericarp, projecting slightly between the seeds, 
finally opens longitudinally into two valves. The seeds, variable 
in number, are reniform or ovoidal, attached to the fruit by an 
elongated ill-developed hilum. Within their coats is a fleshy 
starchy embryo, whose thick cotyledons are applied together by 
their flat faces, and whose radicle lies near the middle of the inner 
border of the seed, next the hilum. The Kidney-beans are erect 
or twining herbs, rarely woody at the base. Their leaves are alter- 
nate, pinnately trifoliolate or rarely unifoliolate, with two lateral 
persistent stipules. Each leaflet has a pedicel, articulated at its 
base where it is accompanied by one or two stipules. The flowers 
are collected next the axils of the leaves into simple or multiple 
racemes. ‘The lower part of the peduncles is bare below.? This 
genus contains some fifty species from all warm countries.’ 
The spiral keel is also found in the two neighbouring species, 
each forming a genus of itself, namely Minkelersia galactioides Marv. 
& Zvcc., from Mexico, which only differs from Phaseolus in the form 
of the pieces of the perianth and in its inflorescence ; and Physostigma 
venenosum Baxr.,‘ a native of Africa, known by the name of Calabar- 
or Ordeal-bean (Féve de Calabar). It has the flowers of Phaseolus, 
but the style is broadly dilated into a triangular blade above the 
stigma (fig. 154); and its voluminous pod contains large seeds with 
tough coats down one side of which runs a long narrow umbilical 
cicatrix extending more than half round the seed (fig. 155). 
The keel is obtuse or merely bowed or beaked in Vignee, which 
subseries comprises besides Vigna the four genera Dolichos, Voandzeia, 
Pachyrhizus, and Psophocarpus, all very closely allied. The character 
1 The ovules are descending, completely or Je. Rar., t. 558.—Wiaut, Icon., t. 34, 249, 
incompletely campylotropous (fig. 152), withthe 755.—Watt., Pl. Asiat. Rar, t. 6, 63,— 
micropyle upwards and outwards. They have Bentu.,in Mart. Fl. Bras., Papil., 180, t. 49.— 
two coats, Gren. & Gopr., Fl. de Fir, i. 457.—Bot. Reg. 
2 BentTuam (loc. cit.) divides this genus into _t. 341, 743.— Bot. Mag., t. 4076.—Watp., Rep, 
six artificial sections: Drepanospron, Eupha- i. 770; ii. 901; v. 587; Ann, i. 2513 ii. 426; 
seolus, Leptospron, Strophostyles, Macropti- iv. 560.—Baxzr, in Oliv., Fl. Trop. Afr., ii. 191. 
liwm, and (?) Dysolodiwm. * For the details of this genus and the suc- 
3 Jacq., Hort. Vindob., t. 66, 90,100,114; ceeding ones see they Genera, p. 233. 
