Ordek 102.— P0LYG0NACBL(E. 60Y 



men. — Herbs or shrubs with very narrow, deciduous Ivs., and the small 



fls. solitary in each ochrea. (Polygonum, Nutt., &c.) 



§ Flowers subscssile. Filaments all flliforni. Leaves broader above, spatulato Nos. 1, 2 



§ Flowers on capillary pedicels 2" long. 8 inner filaments dilated at base. Lvs. linear .Nos. 8, 4 



1 P. parvifolia Mx.' Somewhat shrubby; branches strict, leafless above; hs. 

 liTiear-cuneate, obtuse; panicle compound, spreading; rac. numerous, sessile, fili- 

 form, short, with imbricated bracts ; fls. subsessile ; inner sep. oval, soon equaling 

 the acute achemum, 2 outer reflexed. — Pino barrens, N. Car. to Fla., Ala. and Ark. 

 A delicate, much branched shrub, 1 to 2f high. Sts. brittle, brownish. Lvs. 1' 

 long, 1 to 3" wide above, tortuously spreading. ' Fls. minute, white. 



2 P. grdoile Nutt Anniml, glaucous; branches filiform, paniculate; lvs. epaiu- 

 laie, obtuse, 3 to 5-veined ; rac. almost capillary, bracts approximated ; pedicels 

 very short, reflexed; sep. reflexed-spreading, at length the 3 intier exceeding the 

 acwminate fruit. — Dry, sandy places, Car. to Ma. and La. Sts. strict, furrowed, 2 

 to 3f high. Brandling issuing from between tho joints. Lvs few, 1' to 18" long. 

 Fla. nodding, 1" long, longer than the peduncle, white or flesh-colored. 



3 P. Meianeridna Shutt. Shrubby, very leafy; lvs. linea/rfiliform, obtuse, 

 nearly perennial, glaucous ; achreas subimbricated, green with a conspicuous white, 

 membranous border ; rac. many-flowered ; aohrete 1-flowered, with setaceously 

 acuminate bracts ; 2 outer sepals reflexed. — ^Near Macon, Ga. (Mettauer) and Ala., 

 rare. A delicate, bushy shrub, 1 to 2f high. Lvs. 6 to 10" long, somewhat terete 

 and fleshy. Pla. roseate or white, on jointed, solitary pedicels 2" long. 



4 P. articul^tum. Meisn. Si. erect, with erect branches, soon nearly naked; lvs. 

 linear, caducous from the top of the tubular, truncate sheaths ; spikes panicled, 

 filiform ; fls. solitary, pedunculated, with imbricated, truncated bracts ; sep. erect- 

 spreading. — ^2) N. T. to Mioh., in dry grounds. St slender, strict, 1 to 2f high. 

 Lvs. 6" to If by 1", obtuse. Pis. flesh-colored, showy, 1" long, on nodding, hair- 

 like peduncles. Ach. npt inclosed, triangular, acuminate. Aug. — A true Poly- 

 gonella in habit and character, as the genus is defined by Meisner. 



7. POLYG'ONUM, L. Knot-gbass. (Gr. Tro/liif, many, yov?;, knee; 

 t. c, plant with many joints.) Calyx of 6 sepals, rarely fewer, colored or 

 greenish, similar, imbricated in bud, at length all connivent, persistent ; 

 stamens 8, rarely fewer ; styles 2 or 3, mostly 3, short filiform ; achenia 

 3-cornered or lens-shaped, inclosed in the dry, withered calyx ; embryo 

 curved, lateral, lying in a groove at one angle of the albumen. — A vast 

 genus of herbs with oclireate-jointed stems and small, white, red, or 

 greenish fls. 



5 Stems armed with retrorse prickles, Leaves cordato sagittate. Tisiaria Nos. 19, 20 



S Stems unarmed, twining. Leaves cordate-hastate. Ecjiinocaitlon Nos. 17, 18 



I Stems erect or decumbent, unarmed. Leaves hardly ever cordate. (*) 



* Calyx unequally 4-cleft. Styles 2, long deflexod. Tovakia No. 16 



* Calyx equally 5-parted. Styles erect, (a) 



a Biieaths salver-form. Stamens 7. Stylo 3-parted. Tall. Ambltogomum.No. 15 

 a Sheaths snboylindrical. Stamens 5, 6, 8. Styles 2 or 8. (b) 



b Flowers in leafless, terminal, spike-like racemes. PEnsicAitrA. (c) 



C Eaceme one, dense. Stem at base or rhizome decumbent Nos. 18, 14 



C Eaoemes several. Sheaths naked, not fringed Noa. 11, 12 



Kacomes several. Sheaths bristly fringe-ciliate. (d) 



d Style 2 (or 8)-oIeft. Achenia flat or lens-shapod Nos. S— 10 



d Style 8-cleft. Achenia sharply 8-oornered Nos. C — 7 



d Flowers axillary or seldom forming a leafy r.acome. (e) 



e Aohenium protruding beyond the calyx, 8-anglert Nos. 8, 4 



e Aohenium included in the calyx, 3-angled Nos. 1, 2 



X p. aviculare L. Bird's Knot-GRASS. St. procumbent; lvs. elliptical-lanceolaie, 

 roufh-edged, acutish at each end; fls. subsessilo; ach. striate, dull, inclosed; stam. 

 5 to 8.—^) A common weed in flelds, highways and door-yards, TJ. S. and Brit 

 Am. Sts. slender, i to IJf loUg, striate, smooth, branching, with short, white, 

 torn, remotely veined stipules at the joints. Lvs. smooth, except the edges, 1' 

 by 3'', more or leas. Pis. reddish, small, 2 or 3 together in the axils of the leaves, 

 appearing all summer. (P. littorale Meisn.) 



