252 



DIOSCOREACEM. 



[ DlOSCOREA, 



Stems twining to the right ; seeds with the 

 wing developed all round : 



Section ENANTIOPHYLLUM. Tubers vertical, 

 usually edible. Leaves simple. Male 

 flowers sessile, on short axes, opening but 

 a little way ; perianth -lobes free, with the 

 stamens inserted at their bases ; filaments 

 simple. Seeds in capsules which are not 

 refiexed but face forwards : 

 Male flowers in spikes arranged on elongate 

 leafless branches : 



Flowers of male plant on axes which 

 are never zigzag alive or dry ; buds 

 usually flattened at the base : 



Special flowering branches conspicu- 

 ously shorter than the leaves ; cap- 

 sules often rather glaucous . 5. D. Wallichii. 



Special flowering branches, when well- 

 grown, longer than the leaves : 



Pubescence abundant on the leaf- 

 less axes which bear the spikes 

 of the closely packed male 

 flowers which are covered with 

 hairs, stamens 6 . . 6. D. anguina. 



Pubescence absent entirely : 



Leaves hastate, network con- 

 spicuous below . . . 7. D. belophylla. 



Leaves cordate or ovate-cordate, 



thin, curling up on the midrib 



$ when drying ; the first lateral 



pair of nerves rather close to 



the midrib . . . . 8. D. glabra. 



Flowers of male plant on axes which 

 become zigzag either in life or when 

 dry ; stems acutely angled or winged 9. D. alata. 



Section COMBILIUM 



1 D. aculeata Linn. Amoen. Acad. iv (1754), 131 ; Prain 

 and BurUll in Journ. As. Soc. Beng. (N.8.), Vol. x (1914) ; D, 



