23. (17.) Spadix covered with fertile flowers to the top. Ovary with 4 or more ovules. Leaves sagittate or hastate. Spathe funnel-shaped.--Species 10. South Africa and southern Central Africa; one species (_Z. aethiopica_ Spreng.) cultivated as an ornamental plant under the name of “Calla” and naturalised in the island of Madeira. (_Aroides_ Heist., _Richardia_ Kunth). [Tribe ZANTEDESCHIEAE.] =Zantedeschia= Spreng. Spadix ending in an appendage which is glabrous or covered with rudimentary flowers, rarely without an appendage, but then ovary 1-2-ovuled and leaves dissected. 24 24. Ovules inverted. Ovary usually 2-4-celled. Male and female portions of the spadix contiguous, rarely separated by a glabrous interval without barren flowers. Leaf 1, dissected. [Tribe AMORPHOPHALLEAE.] 25 Ovules straight. Ovary 1-celled. Seeds albuminous. Spadix with a terminal appendage. [Tribe AREAE.] 27 25. Spadix ending in a flowerless appendage.--Species 35. Tropics. Some have edible tubers or are used as ornamental plants. (Under _Amorphophallus_ Blume). (Plate 12.) =Hydrosme= Schott. Spadix covered with flowers to the top; upper flowers sometimes reduced to barren stamens. 26 26. Ovary 1-celled. Male inflorescence as long as the female. Spathe boat-shaped.--Species 7. Central Africa. Some have edible tubers. =Anchomanes= Schott Ovary 2-celled. Male inflorescence longer than the female.--Species 2. Equatorial West Africa. (Including _Zyganthera_ N.E. Brown). =Pseudohydrosme= Engl. 27. Spadix unisexual (containing male or female flowers only). Stamens 2-4. Ovules basal. Leaves dissected.--Species 4. East Africa. Some are poisonous. =Arisaema= Mart. Spadix bisexual (containing both male and female flowers). 28 28. Male inflorescence contiguous to the female. 29 Male inflorescence separated from the female by a distinct interval usually covered with rudimentary flowers. 30 29. Stamen 1. Anther opening by a slit. Ovules basal. Leaves sagittate or hastate.--Species 2. North Africa. Used as ornamental plants. The tubers are poisonous when raw, but edible when cooked, and furnish starch, medicaments, and a substitute for soap. =Arisarum= Targ. Tozz. Stamens 3-4. Anthers opening by pores. Ovules basal or apical. Leaves several dissected.--Species 2. North-west Africa. Used as ornamental plants. The tubers are poisonous when raw, but edible when cooked, and furnish starch, medicaments, and a substitute for soap. =Dracunculus= Schott 30. Interval between the male and the female inflorescence without rudimentary flowers. Spathe divided into two chambers, one of which contains a female flower, the other one several male flowers. Stamens 2. Ovules numerous. Leaves ovate.--Species 1. North-west Africa (Algeria). =Ambrosinia= Bassi Interval between the male and the female inflorescence clothed with rudimentary flowers. Spathe not 2-chambered. Female flowers several. 31