250 DIOSCOEEACEM. [ DIOSCOBEA. 



roots, or with sometimes an epigseal and often woody tuber. 

 Leaves alternate or opposite, simple or compound, costate and 

 reticulate ; petioles often angular and twisted at the base, some- 

 times articulate. Flowers small, usually 1 -sexual, arranged in 

 spikes or racemes, dioecious or monoecious in separate spikes, regular ; 

 bracts often minute, sometimes obsolete ; male spikes or racemes 

 simple or panicled ; female simple, sometimes reduced to 1-2 

 flowers ; perianth superior, MALE flowers : Perianth campanulate 

 or rotate, deeply 6-fid-or urceolate with narrow mouth and short 

 spreading lobes. Stamens 6, inserted at the base of the perianth, 

 all perfect or 3 reduced to staminodes, or only 3 and no staminodes, 

 filaments incurved or recurved ; anthers small, 2-celled, globose, 

 oblong or didymous, or with the cells discrete on branches of the 

 filament. Pistillode thick, columnar, 3-fid. or entire or obsolete. 

 FEM. flowers : Perianth smaller than in male, 6-fid. or-partite, 

 persistent. Staminodes 3, 6 or none. Ovary inferior, 3-quetrous, 

 usually 3-celled ; styles 3, very short ; stigmas entire or 2-fid., 

 recurved ; Ovules 2 in each cell, superposed, pendulous. Fruit a 

 berry or a 3-valved capsule. Seeds flat or globose ; embryo 

 small, enclosed in the fleshy and rather hard albumen. Species 

 about 160, in tropical and subtropical regions. Tamus communis, 

 L., the Black bryony, is a climbing plant with tuberous roots, and 

 is frequently met with in hedges in many parts of Britain. 



DIOSCOBEA, Linn. ; Fl. Brit. Ind. vi, 288. 



Herbs with slender climbing, rarely procumbent, stems ; tuber 

 solitary, often large, underground or rarely epigceal, very rarely 

 with clustered long-peduncled tubers at the base of stem. Leaves 

 alternate or sometimes opposite, entire or lobed or digitately 

 3-9-foliolate. Flowers 1 -sexual and usually dioecious. MALE 

 flowers : Perianth campanulate rotate or urceolate; lobes short, 

 spreading. Stamens 6, free round a pistillode, or connate in a 

 central column, or 3 alternating with 3 staminodes, or 3 without 

 staminodes ; anthers small, the cells contiguous or discrete. Pis- 

 tillode thick and fleshy or none. FEM. flowers: Perianth- segments 

 6, small, free. Staminodes 6, 3 or none. Ovary 3-celled, stigmas 

 reflexed above the style. Fruit a 3-cornered loculicidal capsule, 

 the angles laterally flattened and almost winged. Seeds compressed, 

 often with a large membranous wing ; albumen fleshy or hard, 2- 



