The dried
seed of Physostigma venenosum (family Leguminosae), a
vine of
western Africa; it contains the
alkaloids physostigmine (eserine), eseramine,
eseridine (geneserine) and physovenine; in
toxic doses it causes vomiting, colic, salivation, diarrhoea, convulsions, sweating, dyspnea, vertigo,
slow pulse, and
extreme prostration.
Synonym: Calabar bean,
ordeal bean.
Origin: G. Physa, bellows, + stigma, a mark, spot; so called because of the
shape of the stigma