250 ' : DIOSCOREACEZ. [ Droscorza. 
roots, or with sometimes an epigeal 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, dicecious or moneecious 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. Frust 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.—T'amus communis, 
L., the Black bryony, is a climbing plant with tuberous roots, and 
is frequently met with in hedges in many parts of Britain. 
DIOSCOREA, Linn. ; FI. 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 diccious. Mae 
flowers: Perianth campanulate rotate or urceolate ; lobes short, 
epreading. 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. Pits- 
itllode thick and fleshy or none. Frm. 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- 
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