POLYGONACEAE 187 
42. POLYGONACEAE (SMARTWEED FAMILY) 
Herbs, sometimes undershrubs, or somewhat woody vines. Leaves simple, 
alternate, entire (much reduced or wanting in Muehelenbeckia), the stipules 
usually scarious and sheathing the stems. Flowers usually perfect, some- 
times dioecious, jointed on their pedicels. Perianth of 3 to 6, free or 
connate, persistent, usually accrescent and persistent sepals, often petaloid. 
Petals none. Stamens 5 to 8, rarely more or less, opposite the sepals. 
Ovary free, usually 2- to 4-angled, 1-celled, 1-ovuled. Fruit a small, 
1-seeded nut, usually 3-angled and enclosed by the sepals. 
Genera 30, species about 750 in all parts of the world, 3 or 4 genera 
and about 20 species in the Philippines. 
Herbs with lanceolate leaves, the stipules sheathing the stems. 
1. Polygonum 
Tendril-bearing vines with cordate leaves...................-22::..::--+--- 2. Antigonon 
Leafless shrubs with flattened, striate, jointed branches bearing small 
fascicled flowers at the nodes.......................................... 8. Muehelenbeckia 
1. POLYGONUM Linnaeus 
Glabrous or pubescent herbs with alternate, entire leaves, and mem- 
branaceous, tubular, sheathing stipules. Flowers perfect, small, clustered, 
the clusters arranged in cylindric or slender, spike-like, usually solitary, 
peduncled racemes; pedicels usually jointed; bracts and bracteoles tubular. 
Perianth 38- to 5-cleft, the outer 2 sepals usually smallest. Stamens usually 
5 to 8, perigynous. Ovary usually 3-angled. Fruit usually 3-angled, 
included in the, more or less enlarged calyx. (Greek “many” and “knee,” 
from the numerous joints.) 
Species about 200 in all warm regions, about 15 in the Philippines. 
Leg RO ll aie elle thet oa aan ties whe ee 1. P. barbatum 
OL AIS 2 2S ana ta GE Sa eed eels heme Sena OS 2. P. tomentosum 
1. P. barbatum L. 
An ascending, slightly pubescent or nearly glabrous plant 30 to 60 cm 
high, the stems often prostrate below. Stipules sheathing, cut into long, 
filiform cilia which are longer than the tube. Leaves lanceolate, acuminate, 
10 to 15 em long, glabrous or nearly so except the ciliate margins and 
midrib. Inflorescence terminal and in the upper axils, sparingly branched, 
the racemes erect, peduncled, 2 to 6 cm long, 5 to 7 mm in diameter, 
the bracts close, ciliate. Perianth white, or purplish, about 2 mm long. 
Along the river near Fort McKinley, fl. Mar.Apr., and probably in 
other months; throughout the Philippines. Tropical Asia, Africa, and 
Malaya. 
2. P. tomentosum Willd. 
An erect or ascending pubescent plant, the stems stout, about 1 cm 
in diameter, simple or sparingly branched, usually less than 1 m high. 
Leaves lanceolate, long-acuminate, softly pubescent, 12 to 20 cm long, the 
stipules thin, strigose, truncate, ciliate, surrounding the stems, 1.5 to 2 em 
long. Racemes few, panicled, erect or slightly nodding, peduncled, 2 to 10 
