372 POLYGONACEAE 



lated toward the calyx where the edges are revolute, longer than the peduncles, some- 

 what scurfy : sepal-wings ovate, 1-2 mm. long, reticulate with several transverse nerves, 

 armed with several spreading spine-like teeth, each bearing a minute callosity : outer 

 sepals reflexed or spreading, nearly as large as the wings : achenes oblong-ovoid, 1-3 mm. 

 long, the angles slightly margined. 



In waste places, Louisiana. Adventive from Europe. 



3. FOLYGONELLA Michx. 



Rigid caulescent shrubby herbs. Stems erect or nearly so, conspicuously jointed, 

 striate, the branches partially adnate to the internodes. Leaves alternate : blades, narrow, 

 or cuneate, rather leathery, jointed near the top of the ocreae. Ocreae cylindric. Flowers 

 polygamo-dioecious, on solitary jointed pedicels. Ocreolae imbricated. Sepals 5, petaloid, 

 usually white or rose, persistent, the 3 inner usually developing wings. Stamens 8 : fila- 

 ments subulate. Ovary 3-angled : styles short : stigmas capitate. Ovule erect. Achenes 

 3-angled, invested by the accrescent calyx. Embryo nearly straight, axile. JOINTWEED. 



Ocreae fringed with a few bristle-like cilia. 1. P. ciliata. 



Ocreae naked. 



Leaf-blades 1-5 mm. broad : sepals 1-2 mm. long. 



Achenes rhomboid al : leaves iiliform-spatulate. 2. P. brachystachya. 



Achenes ovoid or oblong-ovoid : leaves with cuneate or spatulate blades. 



Stems branched above : outer sepals not reflexed. 3. P. gracilis. 



Stems diffusely branched at the base : outer sepals reflexed. 4. P. polygama. 



Leaf-blades 5-25 mm. broad : sepals 2.5-3.5 mm. long. 5. P. macrophylla. 



1. Polygonella ciliata Meisn. Annual, very slender, bright green. Stems erect, 

 6-9 dm. tall, branched throughout, the branches wiry, ascending : leaf-blades filiform, 

 2-4 cm. long, often less than 1 mm. wide, acute : ocreae nerved, slightly oblique, fringed 

 with bristle-like yellowish cilia : racemes few, mostly terminal, 2-3 cm. long : ocreolae 

 funnelform, each prolonged into a sharp tip at the back : calyx nearly 3 mm. broad, 

 white or rose : sepals oblong, obtuse. 



In sandy soil, near the Manatee River, Florida. Summer and fall. 



2. Polygonella brachystachya Meisn. Perennial, very slender. Stems branched, 

 2-6 dm. tall, the branches wiry, erect or ascending, nearly strict, the branchlets short : leaf- 

 blades filiform -spatulate, 5-13 mm. long, narrowed from the obtuse apex to the base : 

 ocreae slightly oblique, nerved : racemes very short, about 1 cm. long, disposed in 

 elongated panicles : ocreolae obliquely funnelform, bluntly pointed at the back : pedicels 

 as long as the peduncles : calyx about 2 mm. broad : sepals oblong, truncate or rounded at 

 the apex : sepal-wings orbicular-ovate, 2 mm. long : achenes rhomboidal, nearly 2 mm. long, 

 brown, equally pointed at both ends. 



In sand or sandy soil, peninsular Florida. Summer. 



3. Polygonella gracilis (Nutt. ) Meisn. Annual, very slender, glaucescent. Stems 

 erect, 3-16 dm. tall, strict, branched, especially above, the branches usually filiform : leaf- 

 blades spatulate, 1-4 cm. long, obtuse, sometimes prominently 3-nerved, remote, commonly 

 shorter than the internodes, sometimes persistent : ocreae very slightly oblique, strongly 

 nerved : racemes slender, 2-8 cm. long, disposed in an open panicle on the sterile plant, 

 more contracted on the fertile : ocreolae funnelform, slightly oblique : pedicels much 

 shorter than the peduncles : calyx 2.5 mm. broad, white or pink : sepals nearly equal, 

 oblong or oblong-obovate, rounded at the apex, all slightly accrescent, the inner ones 

 more so than the outer: sepal-wings not conspicuous, ovate, 2.5-3 mm. long: achenes 

 oblong or oblong-ovoid, long-attenuate, 3.5 mm. long, brown. 



On sand hills, South Carolina to Florida and Louisiana. Fall. 



4. Polygonella polygama (Vent.) A. Gray. Perennial by a woody base, slender, 

 glaucescent. Stems diffusely branched near the base, the branches spreading, 3-6 dm. long, 

 wiry, more or less zigzag : leaf-blades wedge-shaped or spatulate, 1-3 cm. long, persistent, 

 commonly longer than the internodes, clustered on the sterile branchlets, remote toward the 

 ends of the branches, 3-nerved at the base : ocreae cylindric, oblique at the top : racemes 

 2-4 cm. long, disposed in elongated or corymbose panicles : ocreolae obliquely funnelform, 

 bluntly pointed at the back : pedicels as long as the peduncles : calyx 3-4 mm. broad, white, 

 rose or yellowish : sepals oblong or obovate-oblong, obtuse, the 3 inner developing wings : 

 sepal-wings ovate or orbicular-ovate, 2 mm. long: achenes ovoid, brown, 1.5 mrn. long, 

 pointed at both ends but less so at the base. 



In dry sandy soil near the coast, North Carolina to Florida. Summer and fall. 



5. Polygonella macrophylla Small. Perennial, stout, glaucous. Stems erect, 8 dm. 

 tall, simple below, branched above : leaf-blades obovate or oblanceolate, 2-6 cm. long or 



