91 



Linn, in part or I), daemona, Boxh ) . Just as D. liirsuia is a most 

 important famine food of India and Malaya, so does D. dumetorum 

 .appear to be a famine food in Africa; but it appears to be more, 

 for whereas D. hlrsuia has given no cultivated races, D. dumeforum 

 has; and the conflicting statements of travellers as to its utility 

 .are to be explained in the light of this. 



Two very distinct races are in cultivation in Singapore : in the 

 one the tubers are lobed; in the otlier the tubers are star-shaped. 

 The plate shows both. The bluntly lobed tubers were from a stock 

 received as Nfamko from the Gold Coast ; while the star-shaped 

 tubers from one called Esura in Southern Nigeria. With the 

 original tubers of Nfamko was received a memorandum stating that 

 Nfamko is edible but medicinal. Esura has been eaten in Singa- 

 pore without causing any discomfort, but it is slightly bitter. 



Bearing the name of Esura there are again two races distin- 

 guished by tbeir colour, the flesh in one being white and the flesh 

 in the other being yellow. That this should be so is most interest- 

 ing because I). Jiisinda exhiloits the same variation in colour being 

 sometimes yellow and sometimes white, but as regards it as yet 

 the colour has not been shown to lie a racial cliaracteristic. 



When D. dumetorum sprouts, it tlirows up a stout prickly 

 shoot, with alternate leaves ;_ and these leaves have the peculiarity 

 that the base of the petiole is bent downwards sharply in such a 

 way as to aid the plant in climbing by preventing the stem from 

 slipping back over its support. It is most interesting to find in 

 D. dumetorum as well as the White and the Yellow Guinea Yams — 

 .species all of the same region — the need of holding to its support 

 met in a slightly different way. 



The leaves of D. dumeiorum are compound; at the apex of a 

 prickly petiole are three leaflets, which when young are sparingly 

 hispid above, then glabrescent, but on the back at all times densely 

 shortly hispid-pul^escent. The middle leaflet is obovate, and usual- 

 ly very long acuminate; tlie lateral leaflets are of the same shape 

 in the inner lialf, but as regards the outer are cordate, and often 

 with a lateral lobe. Towards the apices of the stems the middle 

 leaflet is often smaller than the lateral leaflets. 



Inflorescences arise in the leaf axils towards the ends of thp 

 ;stems. If male a pyramid of spikes is produced, which may be up 

 to 10 cm. long : the axes and the bracts are densely stiffly pubescent, 

 .and the thin glabrous orbicular-ovate sepals peep out from among 

 the hairy bracts. These sepals exposing the green ovate petals 

 open at flowering rather more widely than do those of the flowers 

 ■of the White or the Yellow Guinea Yam a movement facilitated by 

 thinness; they are ovate and rounded above. The petals are only 

 a very little smaller than the sepals; and there are six introrse 

 stamens within. 



The female spike may attain as much as 70 cm. when the 

 fruit is ripening; it carries some 30 — 40 floAvers. The fruits are 

 •elongated and very like those of D. liispida. 



