6. POLYGONEL'LA, Mx. (Lat. diminutive, implying a little or dwarf Polygonum.) Calyx 5-scpalcd, colored, persistent and withering, erect-spreading, or at length the 3 inner sepals increasing and conni-vent; stamens 8, included; styles 3 or almost wanting; achenia 3-cor-uered, naked or inclosed in the 3 inner sepals become scarious valves; embryo straight, axile or lateral in a groove at the angle of the albumen. - Herbs or shrubs with very narrow, deciduous lvs., and the small fls. solitary in each ochrea. (Polvsronum. Nutt.. etc.)
§ Flowers subsessile. Filaments all filiform. Leaves broader above, spatulatc.........................
§ Flowers on capillary pedicels 2" long 3 inner filaments dilated at base. Lvs. linear,
1 P. parvifolia Mx. Somewhat shrubby; branches strict, leafless above; lvs. linear-cuncate, obtuse; panicle compound, spreading; rac. numerous, sessile, filiform, short, with imbricated bracts; fls. subsessile; inner sep. oval, soon equaling the acute achenium, 2 outer reflexed. - 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. gracile Nutt Annual, glaucous; branches filiform, paniculate; lvs. 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 the joints. Lvs. few, 1' to 18" long. Fls. nodding, 1" long, longer than the peduncle, white or flesh-colored.
3 P. Meisneriana Shutt. Shrubby, very leafy; lvs. linear-filiform, obtuse, nearly perennial, glaucous; achreaae subimbricated, green with a conspicuous white, membranous border; rac, many-flowered; achreae 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. Fls. roseate or white, on jointed, solitary pedicels 2" long.
4 P. articulatum Meisn. St. 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. - N. Y. to Nich., 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. many, knee; i. e., 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-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 ochreate-jointed stems and small, white, red, or greenish fls.
§ Stems armed with retrorse prickles. Leaves cordate sagittate. Echinocaulon.. ......
Nos. 20, 21
§ Stems unarmed, twining. Leaves cordate-hastate. TINIARIA.................................
§ Stems erect or decumbent, unarmed. Leaves hardly ever cordate. (*)
* Calyx unequally 4-cleft. Styles2, long defleded. TOVARIA.........................
* Calyx equally 5-parted. Styles erect (a)
a Sheaths salver-form. Stamens 7. Stylo 2-partcd. Tall. Ambltogomum.
a Sheaths subcylindrical. Stamens 5, 6, 8. Styles 2 or 3. (b)
b Flowers in leafless, terminal, spike-like racemes. Persicaria. (c)
c Raceme one, dense. Stem at base or rhizome decumbent
Nos. 13, 14
c Racemes serveral. Sheaths naked, not fringe-ciliate. (d).......
c Racemes several. Sheaths bristly fringe-ciliate. (d)
d Style 2 (or 3)-elefs. Achenia flat or lens-shaped...
Nos. 8 - 10
d Style 3-cleft Achenia sharply 3-cornered........
Nos. 5 - 7
b Flowers axillary or seldom forming a leafy raceme, (e)
e Achcnium protruding beyond the calyx, 3-angled........
Nos. 3, 4
e Achenium included in the calyx, 3-angled........................................
Nos. 1, 2
1 P. aviculare L. Bird's Knot-grass. St. procumbent; Ivs. elliptical-lanceolate, rough-edged, acutish at each end; fls. subsessile; ach. striate, dull, inclosed; stam. 5 to 8. - A common weed in fields, highways and door-yards, U. S. and Brit. Am. Sts. slender, 1/2 to 1 1/4f 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 or 3 together in the axils of the leaves, appering all summer. (P. littorale Meisn.)
γ. erectum. Stems ascending or erect; lvs. larger, elliptic or oval, petiolate; fls. pedicellate; stam. mostly 5. - In richer or shady soils, more common westward. (P. erectum L.)
2 P. tenue Mx. St. slender, rigid, erect, with long, simple branches, acute-angled; lvs. linear-lanceolate and linear, erect, acute; sheaths (stipules) bristly-fringed at top; fls. alternate, subsolitary; ach. included. - A small, slender plant, on rocky soils, N. Eng. to the Mts. of Ga. and Wis. St. 6' to If high. Lvs. 1 to 1 1/2' long, 1 to 2" wide, 3-veined, sessile. Fls. white. Jl, Aug.
3 P. maritimum L. Prostrate, diffusely branched, glaucous; st. striate, with very short internodes; sheaths gibbous at base, hyaline, torn; lvs. fleshy, oval or linear-oblong, nearly veinless; fls. sessile; ach. sharply angled, a little exserted, smooth and shining. - Sandy shores, R. I. to S. Car. Sts. 6 to 12' long. Lvs. few and small, 2 to 4" long. Fls. often crowded in leafy racemes, rose-purple, green at base, 1" long. (P. aviculare, β. glaucum, 2d edit.)
4 P. ramosissimum Mx. St. tall, erect or ascending, much branched, striate; sheaths 6-veined, at length torn; lvs. lance-oblong or linear, petiolate; fls. subsolitary, pedicellate, greenish; ach. exserted, smooth but dull. - Sandy shores of streams and lakes, Mich, to Ill. Much like P. aviculare, but rigidly erect, 2 to 3f, with larger, petiolate lvs. 2' long, and larger sepals, 1 1/2" long in fruit, green, with narrow white borders.
5 P. hirsutum Walt. Hairy Knot-grass. Hirsute, with long, spreading, tawny hairs; sheaths ciliate; lvs. lanceolate, obtuse at base, gradually narrowed to the point; spikes 2 or 3, very slender; bract equaling its 2 or 3 pedicels; stamens 7 to 8; style 3-cleft; ach. shining. - Swamps, N. Car. to Fla. St. slender, rooting at base, ascending 2 to 4f. Lvs. 2 to 3' by 4 to 10", mostly smooth above, sometimes dense-hairy like the stem. Fls. white. May - Aug.