ORDER 102. POLYGONACEJ3. 607 



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

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



Flowers subsessile. Filaments nil filiform. Leaves broader above, spatukto Nos. 1, 2 



Flowers on capillary pedicels 2" long. 8 inner filaments dilated at base. Lvs. linear. Ni*. 3, 4 



1 P. parvifolia MX. Somewhat shrubby; branches strict, leafless abovo; hv. 

 linear-cuncate, obtuse ; panicle compound, spreading ; rac. numerous, sessile, fili- 

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

 the acute achcnium, 2 outer reflosed. Pine 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. grcile Nutt. Annual, glaucous; branches filiform, paniculate; Ivs. spatu- 

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

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

 acuminate fruit. Dry, sandy places, Car. to Fla. and La. Sts. strict, furrowed, 2 

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

 Fls. nodding, 1" long, longer than tho peduncle, white or flesh-colored. 



3 P. Meisneriana Shutt. Shrubby, very leafy; Ivs. linear-filiform, obtuse, 

 nearly perennial, glaucous ; achrece subimbricatcd, green with a conspicuous white, 

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

 acuminate bracts ; 2 outer sepals reflexed. Near Macon, G-a. (Mettauer) and Alru, 

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

 and fleshy. Fls. roseate or white, />ii jointed, solitary pedicels 2" long. 



4 P. articulatum Meisn. St. erect, with erect branches, soon nearly naked; Ivs. 

 linear, caducous from the top of the tubular, truncate sheaths ; spikes panic-led, 

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

 spreading. 'X> N. Y. to Mich., in dry grounds. St. slender, strict, 1 to 2f high. 

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

 like peduncles. Ach. not inclosed, triangular, acuminate. Aug. A true Poly- 

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



7. POLYG'ONUM, L. KNOT-GRASS. (Gr. rrokvg, many, yow, knee; 

 i. <?., plant with many joints.) Calyx of 5 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-corncred 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 ochreate-jointed stems and small, white, red, or 

 greenish fls. 



Stems armed with retrorse prickles. Leaves cordate sagittate. ECHINOCAULOX Nos. 20, 21 



Stems unarmed, twining. Leaves cordate-hastate. TINIABIA Nos. 1719 



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



* Calyx unequally 4-cleft. Styles 2, long detlexed. TOVAEIA No. 1G 



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



a Sheaths salver-form. Stamens T. Style 2-parted. Tall. AMBLYOGOMTJM.NO. 15 

 a Sheaths subcylindrical. Stamens 5, G, 8. Styles 2 or 3. (b) 



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



C Raceme one, dense. Stern at base or rhizome decumbent Nos. 13, 14 



C Racemes several. Sheaths naked, not fringed Nos. 11,12 



C Racemes several. Sheaths bristly fringe-ciliate. (d) 



d Style 2 (or 8)-clef;. Achenia flat or leas-shaped Mos. S 10 



d Style 3-cleft. Achenia sharply 3-cornered Nos. 5 T 



b Flowers axillary or seldom forming a leafy raceme, (e) 



e Achcnimn protruding beyond the calyx, 3-anglcd Nos. 8, 4 



O Achenium included in tho calyx, 8-anglcd Nos. 1, 2 



1 P. avicularo L. BIRD'S KNOT-GRASS. St. procumbent ; Ivs. elliptical-lanceolate, 

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

 6 to 8. (1) A common weed in fields, highways and door-yards, U. S, and Brit. 

 Am. Sts. slender, 4- to l\f long, striate, smooth, branching, with short, white, 

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

 by 3'', more or less. Fls. reddish, small, 2 cr 3 together in the axils of the leaves, 

 appearing all bummer. (P. littoralo Mcisn.) 



