In various parts of Western Africa it appears to be the practice to subject to the ordeal by poison persons who come under suspicion of having committed heinous crimes. On the banks of the Gambia river the poison used for the purpose is the bark of a leguminous tree, the Fillœa suaveolens of MM. Guillemin and Perottet. In the neighbourhood of Sierra Leone it is the bark of Erythrophleum guinëense, which some botanists have considered identical with the former species. On the Congo river, Captain Tuckey found that either this species, or an allied species of the same genus, was in constant use for the same purpose.