382 POLYGONACEAE 



3.5 mm. long, broadly obovoid or oblong-obovoid, short-tipped, black, granular. \_Poly- 

 gonum Convolvulus L. ] 



Common throughout Northi America, except the extreme north. Naturalized from Europe. BLACK 

 BINDWEED. 



2. Tiniaria cilinodis (Michx. ) Small. Annual or perennial, sparingly pubescent, of 

 a reddish or reddish green tint. Stem prostrate or extensively twining, b'-25 dm. long : 

 leaf-blades broadly ovate or ovate-lanceolate, 2-8 cm. long, acute or acuminate, cordate or 

 subcordate, sometimes inclined to be hastate, petioled, somewhat crisped, minutely ciliate, 

 often prominently nerved on the lower surface : ocreae very oblique, 3-4 mm. long, 

 acutish, fringed with reflexed bristles at the base : racemes 1-10 cm. long, loosely 

 flowered, interrupted : calyx white, 3-4 mm. long : sepals 5, oblong or obovate, obtuse, 

 the three outer ones keeled : stamens 6 or 8 : achenes 3-angled, 3 mm. long, broadly oblong 

 or often nearly ovoid, black, very smooth and shining. \_Polygonwn cilinode Michx.] 



In rocky places, Nova Scotia and New Brunswick to the Rocky Mountains, south to the Great 

 Lake Region ; also in and near the Allegheny Mountains. 



3. Tiniaria dumetorum (L.) Opiz. Perennial, bright green, somewhat scurfy. 

 Stem weak, extensively twining, 6-40 dm. long, much branched : leaf-blades ovate-cordate, 

 2-7 cm. long, acuminate, petioled or nearly sessile toward the ends of the branches : ocreae 

 oblique, 3-4 mm. long, acute or obtusish, glabrous : racemes 3-8 cm. long, usually numer- 

 ous, loose, interrupted, bearing a few small leaf-like bracts : calyx yellowish green, at 

 length 5 mm. long : sepals obtuse, the three outer ones keeled and in fruit much enlarged 

 and conspicuously winged: stamens 8: achenes 3-angled, 2-3 mm. long, oblong, inclined 

 to be pointed at both ends, black, smooth and shining. [Polygonum dumetorum L. ] 



In thickets, Missouri, Illinois and Tennessee. Also in Europe. FALSE BUCKWHEAT. 



4. Tiniaria scandens (L. ) Small. Perennial, more or less scurfy. Stem extensively 

 twining, 1-10 m. long, often copiously branched, roughened on the ridges : leaf-blades 

 ovate or oblong-ovate, 4-12 cm. long, cordate, acuminate, sparingly scabrous or eroded on 

 the margins, papillose : ocreae oblique, 2-4 mm. long, acute, rough on the ridges : racemes 

 3-24 cm. long, interrupted, bearing many large bracts : calyx greenish yellow, at length 

 1 cm. long : sepals obtuse, the three outer ones keeled and conspicuously winged in fruit : 

 stamens 8 : achenes 3-angled, 3.5-4.5 mm. long, oblong, often enlarged about the middle, 

 rather blunt at both ends, black, smooth and shining. \_Polygonum scandens L.] 



In thickets, Nova Scotia to the Rocky Mountains, Florida and Louisiana. HEDGE BUCKWHEAT. 



6. Tiniaria cristata (Engelm. & Gray) Small. Perennial, slender, very scurfy. 

 Stem twining, 5-20 dm. long, more or less branched, somewhat twisted : leaf-blades ovate, 

 triangular-ovate or triangular, 1-6 cm. long, varying from cordate to truncate, acute or 

 acuminate, obscurely eroded, short-petioled : ocreae 2-4 mm. long, hardly oblique : racemes 

 axillary, 2-4 cm. long, loosely flowered, naked, interrupted : calyx greenish white, 4-5 mm. 

 long, the three outer sepals keeled and winged in fruit, the wings more or less incised : 

 stamens 8 : achenes 3-angled, 2.5-3 mm. long, oblong, black, smooth and shining. \_Poly- 

 gonum cristatum Engelm. & Gray.] 



In thickets or woods, New York to Georgia and Texas. 

 



12. BRUNNfCHIA Banks. 



Perennial vines. Stems much elongated, climbing by tendrils arising from the ends of 

 the branches. Leaves alternate : blades entire, truncate or cordate at the base : ocreae 

 obsolete. Flowers perfect, 2-5 in clusters subtended by narrow bracts, disposed in terminal 

 panicled racemes. Pedicels slender, jointed near the base. Hypanthium much enlarged 

 and leathery in fruit, winged on one side near the base and along the pedicel-like base, in- 

 vesting the achene. Sepals 5, spreading or converging when dry. Stamens 7-10, usually 8 : 

 filaments filiform, slender, much dilated at the junction with the sepals. Ovary imperfectly 

 3-celled, 3-angled : styles 3 : stigmas 2-cleft at the apex. Ovule pendulous. Achene 

 3-an^ied, smooth. Seed irregularly 6-grooved. Embryo in one of the angles. 



1. Bmnnichia cirrhosa Banks. A slender shrub, climbing over bushes and trees by 

 means of terminal tendrils. Stems 2-8 m. long, woody and tough : leaf-blades ovate or 

 ovate-lanceolate, 3-15 cm. long, acute or acuminate at the apex, truncate or subcordate at 

 the base, petioled, slightly pubescent beneath : ocreae obsolete, sometimes represented by 

 a ring of short hairs : racemes 3-15 cm. long, naked or nearly so : hypanthium campanu- 

 late, 6-8 mm. long, greenish, winged along the base and pedicel-like base : sepals 5, spread- 

 ing or recurved, but converging at maturity when dry : stamens exserted : achenes oblong- 



