may become quite prominent after fertilization. The floral pattern is 

 based on sets of three. 



The minor species belong to two sections of the genus. D. 

 dumetorum, D. hispida, and D. pentaphylla belong to the section 

 Lasiophyton, and D. nummularia belongs to the section Enantiophyl- 

 lum. We do not know the classification of D. transversa, a species first 

 described in 1810 by Brown (2). Some synonyms and common names are: 



Synonyms Common names 



D. dumetorum 



D. bucholziana Engl Traveller's yam. 



D. deamona Hook Cluster yam. 



D. triphylla Hochst Bitter yam. 



D. vespertilio A. Chev. 



Helmia dum£torum Kunth 



D. hispida 



D. daemona Roxb Asian bitter yam, 



intoxicating yam. 



D. hirsuta Dennst 



D. triphylla L 



D. pentaphylla 



Five-leaflet yam. 



D. nummularia 



D. glabra Koorders non Roxb 



D. hebridensis Kunth 



D. palauensis Kunth 



D. pirita Nadeaud Pacific yam. 



D. seemanii Prain et. Burk 



Umbium nummularium Rumph 



Morphology 



The three species of the section Lasiophyton — D. hispida, D. 

 dumetorum, and D. pentaphylla (figs. 1-3) — share traits common to 

 the section. Their vines are vigorous and twine to the left, the foliage 

 is pubescent, and the leaf is deeply palmately divided into three to 

 five lobes or leaflets. Leaves are alternate, and the stem is often prickly. 

 The inflorescences are special leafless side branches, often large. Al- 

 though D. pentaphylla is easily distinguished from D. hispida and D. 

 dumetorum, the latter two are closely related (in spite of origins on 

 different continents) and are easily confused. 



D. pentaphylla includes many varieties that have sometimes been 

 distinguished taxonomically (var. sacerdotalis , palmata, javanica, 

 papuana, malaica). The tubers are extremely variable. Some are long 

 and penetrate deeply into the soil; others are superficial and globose or 

 even pear shaped (fig. 4). The flesh varies in color from white through 

 cream to light yellow and may be purpled by anthocyanin. One principal 

 stem is produced up to 1 centimeter thick, often with heavy prickles at 



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