THE M0X0C07 YLEDONES 



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segments and either six, or more rarely three, stamens. The ovary is 

 usually inferior, trilocular or occasionally unilocular. The fruit is a capsule 

 bearing endospermic seeds which are often winged. They occur in tropical 

 and warm temperate regions. 



This order was made by Hutchinson to include four families, three of 

 them small with hermaphrodite flowers, which need not concern us here, 

 and one, the Dioscoreaceae, with unisexual flowers, which we must describe 

 briefly. 



The Dioscoreaceae are usually climbers with tuberous rhizomes or 

 thick woody rootstocks. The leaves are alternate and net-veined, often 

 arrow-shaped. The inflorescence is a raceme bearing regular, unisexual 

 flowers, with a perianth of six segments, tubular at the base and enclosing 

 six stamens, three of which may be staminodes. The gynoecium consists of 



Fig. igyg. — Dioscoreo alata. A, Flowering shoot. C, Tubers. Dioscorea batatas. 

 B, Male inflorescence. D, Female inflorescence. E and F, Tubers. 

 (A, C, E, F after Bois. B, D after Le Maoiit and Decaisne.) 



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