8. Carpels containing numerous ovules or seeds, coiled spirally when ripe and contracted between the seeds. Trees.--Species 1. German East Africa. =Polyceratocarpus= Engl. & Diels Carpels containing 2-8 ovules or 1-8 seeds, straight or slightly curved when ripe. 9 9. Petals spreading, subequal. Ovules 2. Stalks of the inflorescence and the flowers usually thickened and hooked. Mostly climbing or scrambling shrubs.--Species 18. Tropics to Delagoa Bay. Some have edible fruits or are used in medicine. =Artabotrys= R. Br. Petals suberect or connivent, the inner shorter and triangular above. Sepals more or less united. Receptacle usually concave. Ovules 2-8, inserted along the ventral suture. Styles long.--Species 30. Tropics. Some yield timber, spices (guinea-pepper), and medicaments. (_Xylopicrum_ P. Br.) =Xylopia= L. 10. (4.) Petals transversely folded, at least in the bud, united at the base, subequal. Carpels 3-12, hairy; ovules numerous; styles 2-cleft.--Species 6. Tropics. [Tribe HEXALOBEAE.] =Hexalobus= A. DC. Petals not folded, usually free. [Tribe UVARIEAE.] 11 11. Petals valvate in the bud. Carpels free. [Subtribe UNONINAE.] 12 Petals, at least the inner ones, imbricate in the bud. [Subtribe UVARIINAE.] 23 12. Petals 3-4. Sepals or calyx-lobes 2. Connective of the stamens not or scarcely prolonged. Carpels and ovules numerous. Flowers unisexual. 13 Petals 6. Sepals 3. Connective usually prolonged beyond the anther-cells. 15 13. Petals 3, thick. Flowers in clusters springing from the old wood, the female somewhat larger than the male. Trees.--Species 1. Equatorial West Africa (Congo). =Thonnera= De Wild. Petals 4. 14 14. Petals free. Flowers in clusters springing from the old wood, the female much larger than the male. Trees.--Species 2. Equatorial West Africa. =Tetrastemma= Diels Petals united below. Flowers solitary, axillary, the female about as large as the male. Shrubs.--Species 1. Equatorial West Africa (Cameroons). =Uvariopsis= Engl. 15. Petals in 1 row, rather thick. Stamens 12, six of them sometimes sterile. Anther-cells ovate. Carpels numerous, 1-seeded.--Species 2. West Africa (Congo). =Monanthotaxis= Baill. Petals in 2 rows. 16 16. Outer petals spreading, inner smaller and converging.--Species 30. Tropical and South-east Africa. (Including _Clathrospermum_ Planch.) =Popowia= Endl. Outer and inner petals spreading or erect. 17 17. Stamens 3-6; connective ovate, prolonged above, but not dilated. Carpels 3, one-seeded.--Species 1. Madagascar. =Bocagea= St. Hil. Stamens numerous. 18 18. Stamens with an acuminate connective. Ovules several. Style short. Fruit slightly constricted between the seeds. Trees. Flowers in axillary clusters.--Species 1 (_C. odorata_ Hook. f. & Thoms., Ylang-Ylang). Cultivated in the tropics for its fragrant flowers, which yield a perfume. =Cananga= Rumph. Stamens with a truncate or rounded connective. 19