Physostigma
(from physa, a bladder, and stigma; the bearded style is terminated by a large, oblique hood covering the stigma). Ordeal Bean of Old Calabar. ORD. Leguminosae. A monotypic genus. The species, P. venenosum, is a tall, climbing herb, shrubby at base, native of tropical Africa. Its seeds "are extremely poisonous, and are employed by the natives of Old Calabar as an ordeal; persons suspected of witchcraft, or other crime, being compelled to eat them until they vomit or die--the former being regarded as a proof of innocence, and the latter of guilt" (Lindley and Moore). This Bean is also remarkable for possessing a property causing contraction of the pupil of the eye.
P. venenosum (deadly). fl. purplish, resembling those of a Bean, axillary, pendulous, rather large, in a fascicled raceme; style bearded, terminated by a large, oblique hood, covering the blunt stigma. Pods dark brown, about 6in. long; seeds oblong or somewhat hemispherical, about 1in. long. l. pinnately tirifoliate, stipellate; leaflets ample. (B. M. Pl. 80.)