One hundred and ninety plants, of which 51 are used to treat malaria in traditional medicine, were collected in five different ecosystems of Madagascar for a screening programme devoted to the search of naturally-occurring antimalarial compounds. Thirty-nine plants, of which 12 are used as herbal antimalarials, were found to display in vitro activity against Plasmodium falciparum with a median inhibitory concentration (IC50) lower than 5 microg/ml while 9 had an IC50 ranging from 5 to 7.5 microg/ml. Seventeen of them exhibited cytotoxic effects on murine P388 leukemia cells with an IC50 < 10 microg/ml. The biological activities were mostly located in the ethyl acetate fractions. Bioassay-directed fractionation is underway to isolate the active constituents.

Solanum mahoriensis D'Arcy & Rakolo/afy, sp. slightly angulate, the lobes ca. 10 mm long (8 nov. type: Cultivated, Missouri Botanical mm long in short-styled flowers), glabrous with-Garden, D'Arcy 15487a. Seed from Mada-in, stellate-pubescent outside except on the sigascar. Antsiranana (Diego-Suarez): forest nuses where puberulent with reduced simple triof Mahory, ca. 6 km S of Marataolana (ca. chomes; stamens 5, equal, the anthers yellow, 12 km S of Anivorano Nord), 12°48'S, subsessile, narrow, 8 mm long (4.5 mm in short-49*^1 4'E (holotype, MO; isotype, TAN, du-styled flowers), the terminal pores minute, the plicates to be distributed). Frutex ad 1 m alius, sparse pubescens pilis slellatis, spinis rectis nemio armatis. Folia lobata, armala, gla-

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