to take muavi with his coordinates from the other vil- 
lages. If a particular man vomited, he vindicated both 
himself and his village from suspicion. But if he retained 
the poison, it meant that either he or someone in his vil- 
lage was the guilty party. A local ordeal then located 
the troublemaker. 
Acokanthera venenata G.Don 
One of the less important muavi plants was Acokan- 
thera venenata G.Don of the Apocynaceae. This plant 
contains several active principles, the most toxic of which 
is a crystalline cardiac glycoside called ouabain (or aco- 
cantherin). In addition to this principle there are amor- 
phous ouabain (also known as acocanthin, abyssinin, or 
G-strophanthin) and a third active ingredient, oxalic acid. 
This plant, whose active principles occur in all parts, 
produced death by heart failure several minutes after the 
ingestion of a concentrated decoction. 
The major principle, ouabain, is a crystallized stro- 
phanthin (Cea9H44O12-8H2O) with about twice the tox- 
icity of normal strophanthin. Its action on the heart and 
respiratory tract is similar to the effects of digitalis poi- 
soning. Amorphous ouabain (Cs2H 50012) has much the 
same effect. 
Oxalic acid (C2H2Ox4) acts merely as an irritant in small 
doses and as a corrosive agent in larger amounts, having 
but a remote inhibitory action on the respiratory and 
cardiac centers. However, it is still toxic even after di- 
lution has inhibited its corrosive and irritative effects. 
Significant to their function in the ordeal is the fact 
that both ouabain and strophanthin are absorbed irregu- 
larly by the digestive tract. There is no means of predict- 
ing the amount that an individual will absorb at a given 
time. Consequently, a dose which was non-fatal to a per- 
son on one day might later cause his death. Under such 
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