Dioscorea. | CXXXIX. DIOSCOREACEH (BAKER). 415 
Stem terete. 
Leaves and flowers glabrous. 
Leaves cordate orbicular . S S . 11. D. zanzibarensis. 
Leaves ovate, shallowly cordate . d : . 12. D. prehensilis. 
Leaves ovate, deeply cordate. : : . 13. D. abyssinica, 
Leaves and flowers hairy . : - : . 14, D. schimperiana. 
Leaves compound. 
Leaves trifoliolate. 
Leaflets subsessile. 
End leaflet obovate . ; . : . . 15. D. dumetorum. 
End leaflet oblong . : S l : . 16. D. phaseoloides, 
Leaflets distinctly stalked `. : : ; . 17. D. Vespertilio. 
Leaves 5- rarely 7- foliolate. 
Male spikes dense. 
Leaflets obovate or oblong : S é . 18. D. beccariana, 
Leaflets lanceolate or oblanceolate . : . 19. D. Stuhlmanni. 
Male spikes lax . : : : : : . 20. D. Holstii, 
1. D. (Helmia) sativa, Linn. Sp. Plant. edit. i. 1033 (exel. syn.). 
Glabrous in all its parts. Rootstock large, tuberous, edible. Leaves 
distinctly petiolate, simple, ovate or orbicular, cuspidate, deeply cordate, 
sometimes 1 ft. long and broad, membranous, 7—9-nerved from the 
apex of the petiole, often bearing bulbils in their axils. Male flowers 
in lax slender fascicled spikes, often produced from leafless nodes ; 
bracts minute, ovate. Perianth 1,-} in. long, oblong in bud ; segments 
linear. Fertile stamens 6. Female flowers in very lax spikes. Capsule 
oblong, 3—1 in. long. Seeds broadly winged at the base only.—Hort. 
Cliff. t. 28; Schum. Beskr. Guin. Plant. 447; Benth. P. Austral. vi. 
461; Hook. f. Fl. Brit. Ind. vi: 295. D. latifolia, Benth. in Hook. 
Niger Fl. 535; D. bulbifera, Harms in Engl. Pü. Ost-Afr. C. 146. 
Commonly cultivated throughout Tropical Africa. 
Upper Guinea. Sierra Leone: Kinsuta, Scott-Elliot, 4235! and without pre- 
cise locality, Don ! Niger Territory: Nupe; Jeba, Barter! at the confluence of the 
Niger and Benue Rivers, Barter! Niger Delta: Nun River, Vogel, 30! Fernando 
Po, Milne! Cameroons: Yaunde, Zenker & Staudt, 412! 
Wile Land. Galabat: Matamma, Schweinfurth, 593! British East Africa : 
Unyoro, Speke & Grant! 
Lower Guinea. Isle of St. Thomas, Moller, 4! Gaboon: Munda; Sibange 
Farm, Soyauz, 77! 211! Angola: Golungo Alto, Welwitsch, 4037 ! 
Mozamb. Dist. German East Africa: Usambara; Duga, Holst, 3160! 
Portuguese East Africa: Lupata, on the River Zambesi, Kirk! Shamo, near the 
mouth of the River Shire, Kirk! British Central Africa: Boruma, on the River 
Zambesi, Menyharth ! Nyasaland; Shire Highlands, Buchanan, 259! and without 
precise locality, Buchanan, 11! 1185! 
2. D. Buchanani, Benth. in Hook. Ic. t. 1397-8. Stems twining, 
glabrous, unarmed. Leaves all alternate, distinctly petiolate, cordate- 
ovate, cuspidate, sometimes as broad as long and palmately lobed, 
reaching $ ft. long, moderately firm, glabrous on both surfaces, 5-7- 
nerved from the apex of the petiole. Male flowers in dense short 
usually solitary axillary racemes; bracts lanceolate, shorter than the 
pedicels. Male perianth glabrous, very large for the genus, } in. long, 
