POLYCJONACEAB 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. 

 Ovajy free," iisually 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 2. Antigonon 



Leafless shrubs with flattened, striate, jointed branches bearing small 

 fascicled flowers at the nodes 3. Muehelenbeckia 



1. POLYGON Uhfl 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 3- to 5-clef t, 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. 



Nearly glabrous 1- P- barbatum 



Densdy pubescent ^ 2. P. tomeniosum 



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. LeSves lanceolate, acuminate, 

 10 to 15 cm 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 Wllld. '^- 



An erect or ascending pubescent plailt, 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 cm 

 long. Racemes few, panicled, erect or slightly nodding, peduncled, 2 to 10 



