6. Perianth cupular. Ovary 1-4-celled with 2 or more ovules in each cell. Juice milky. Leaves sagittate; stalk not thickened near the middle. Spathe-margins connate below.--Species 20. Central and South-East Africa. [Tribe STYLOCHITONEAE.] =Stylochiton= Leprieur Perianth of 4 free segments. Ovary 2-celled with 1 ovule in each cell. Juice not milky. Leaves pinnate; stalk with a thickened joint near the middle. Spathe-margins free. [Tribe ZAMIOCULCASEAE.] 7 7. Stamens with free filaments; anthers opening by slits. Leaves several, once pinnate. Spathe upon a short stalk.--Species 1. East Africa and Mascarene Islands. Used as an ornamental plant. =Zamioculcas= L. Stamens with united filaments; anthers opening by pores. Leaf 1, thrice pinnate in the adult stage. Spathe upon a long stalk.--Species 2. East Africa to the upper Congo. =Gonatopus= Hook. fil. 8. Stamens united throughout their length or almost so. 9 Stamens free or united in pairs or at the base only. 17 9. Female (inferior) part of the spadix adnate to the spathe, 1-flowered. Stamens 2. Floating water-plants. Juice not milky.--Species 1. Tropical and South Africa and Egypt. Used medicinally. [Tribe PISTIEAE.] =Pistia= L. Female part of the spadix free from the spathe, several-flowered. Stamens 3-8, very rarely 2. Land-or marsh-plants. Juice milky. 10 10. Stem creeping. Leaves lanceolate, parallel-veined, with numerous primary and secondary lateral veins. Ovary completely or incompletely 2-3-celled with numerous ovules.--Species 12. West Africa. [Tribe ANUBIADEAE.] =Anubias= Schott Stem erect or tuberous. Leaves ovate, ovate-sagittate or dissected, net-veined, rarely parallel-veined with 5 primary lateral nerves. 11 11. Ovules 1-3. Spadix with barren flowers below and above the male ones. Stem short, ascending. Leaves ovate or sagittate, entire, with about 5 primary lateral nerves and many parallel secondary ones.--Species 2. Madagascar and neighbouring islands and Zanzibar. They yield fibre and edible tubers and seeds and are used in medicine. =Typhonodorum= Schott Ovules 4 or more. Leaves sagittate-or cordate-ovate and net-veined, or dissected. 12 12. Ovules 4. Female flowers with staminodes. Spadix with a terminal appendage. Stem tuberous. Leaves dissected.--Species 1. Seychelles. [Tribe PROTAREAE.] =Protarum= Engl. Ovules more than 4. Leaves sagittate-or cordate-ovate. [Tribe COLOCASIEAE.] 13 13. Ovary completely 1-celled. Ovules straight or almost so. 14 Ovules incompletely 2-3-celled. Ovules inverted. Spadix without a terminal appendage. 16 14. Ovules few, basal. Stem erect. Spadix with a terminal appendage.--Species 1. Cultivated and sometimes naturalised in Madagascar and the neighbouring islands. Stem and leaves are edible; also used as an ornamental plant. =Alocasia= Schott Ovules many, parietal. Stem tuberous. 15