808 Oedee 102.— POiTGONACE^ 



y. EEECrnii. Stems ascending or erect; Iva. larger, elliptic or oval, petiolate; 

 fls. pedicellate ; stam. mostly 5. — In richer or shady soils, more common 

 westward. (P. erectum L.) 



2 P. tinue Mx. Si. slender, rigid, erect, with long, mmpk Irqemhes, acute-angled; 

 Ivs. liTiear-lanceolate and linear, erect, acute; sheaths (stipules) bristly-fringed at 

 top; fls. alternate, subsolitary; ach. included. — A small, slender plant, on rocky 



' soils, BT. Eng. to the Mts. of Ga. and Wis. St. 6' to If high. Lvs. 1 to 1 J' long, 

 1 to 2" wide, 3-veined, sessile. Pis. white. Jl., Aug. 



3 P. maritimum L. Prostrate, diffusely branched, glaucous; si. striate, wiih 

 very short iniemodes; sheaths gibbous at base, hyaline, torn; his. fleshy, oval or 

 linear-oblong, nearly veinless ; fls. sessile; acA. sharply angled, a Uttle exseried, 

 smooth and shining. — If Sandy shores, B. I. to S. Car. Sts, 6 to 12' long. Lvs. 

 few and small, 2 to i" long. Pla. ofl;en crowded in leafy racemes, rose-purple, 

 green at base, 1" long. (P. aviculare, p. glaucum, 2d edit.) 



4 P. ramossfssimum Mx. Si. tail, erect or ascending, much branched, striate ; 

 sheaths 6-veined, at length torn ; lvs. lance-dblong or linear, petiolate ; fls. subsoli- 

 tary, pedicellate, greenish ; ach. included, smooth hut dull. — 3) Sandy shores of 

 streams and lakes, Mich, to 111. Much like P. aviculare, but rigidly erect, 2 to 3^ 

 with larger, petiolate lvs. 2' long, and larger sepals, 1-J-" long in fruit, green, with 

 narrow white borders. 



5 P. hirsitum "Walt. Haibt KN0T-aEAS3. Hirsute, with long, spreading, tawny 

 hairs; sheaths eUiate; 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. slendra-,, root- 

 ing at base, ascending 2 to 4f. Lvs. 2 to 3' by 4 to 10", mostly smooth above, 

 sometimes dense-hairy like the stem. Pis. white. May — Aug. 



6 P. hydropiperoides Mx. Mild "Watee-peppee. Si. smooth; sheaths hairy, 

 bristly -ciliate, long and narrow; lvs. linear-lanceolate, tapering to each end, 

 slightly appresscd-hairy (not acrid) ; spikes 2 or more, slender, loose-flowerid at 

 base; cal. glandless; stam. 8; style half-3-cleft; ach. shining. — T). Ditches and 

 wet ground, common. St. branched, 1 to 3f high. Lvs. narrowed into a short 

 petiole, not acrid. Pis. rather large, white-roseate, rather close, 4 or 6 from' each 

 bract. Aug., Sept. (P. mite Pers.) 



p. SETACEUM. Lvs. lauceolato ; stip. conspicuously fringed with long bristles. 

 — In clayey soils, soutliward. (P. setaceum Baldw.) 



7 P. acre H. B. K. St. ascending, slender, glabrous; sheath smoothish, fringed 

 with bristles, bearing the leaf near the base; lvs. acrid, lanceolate, acuminate, 

 filiform, interrupted at base ; bracts, truncate, 1 to 3-flowered ; ped. scarcely ex- 

 serted; stam. 8; style 3-parted; ach. 3-cornered. — "Wet places, ditches, com- 

 mon S. and "W. Cal. greenish at base, flesh-colored, brown-dotted like the lvs. 

 Ach. shining. Jl. — Sept. (P. puuotatum Ell. P. hydropiperoides Ph.) 



8 P. Hydropiper L. 'Watee-peppeh, Glabrous; sheaths bristly-ciliate ; lvs. 

 lanceolate, lapering to both ends, minutely, pellucid-punctate (very acrid) ; spikes 

 loose-flowered, slender, short (2 to 5') nodding; ped. exserted; cal. glmdnikiir- 

 punctaie ; stam. mostly 6 ; sty. 2 or 3-oleft ; cuih. flattish (rarely obtusely triangu- 

 lar), daill, minutely roughened. — (E Damp waste grounds, ditches, Ac, 1 to 2f high. 

 Lvs. not more than 6" wide. Pis. green and rose-colored. Ach. black. Jl. — 

 Sept. § Eur. 



9 P. CSreyi Olney. St. erect, hirsute, much braawhed; lvs. lanceolate, with scat- 

 tered and appressed hairs; stip. scarious, tubular, truncate, hairy-cUiate ; spikes 

 axillary and terminal, on very long, nodding peduncles thickly beset wiih glandular 

 hairs ; stam. 6 to 8 included : sty. 2 ; ach. orbicular-ovate, mucronate, tumid, 

 shining.— d) Swamps, N. Eng. and N. Y. ? Plant 3 to 5f high. Lvs. 3 to 6' by 

 G" to 1', midvein and margins hairy. Cal. greenish-purple, tmged with white, 

 minutely dotted. 



10 P. Persic^ria L. St. erect ; lvs. lanceolate, the upper surface usually marked 

 with a brownish spot; stip. fringed; spikes dense, oblong, erect; ped. smooth; stam. 

 6 ; sty. 2, half united ; ach. shining, JUUtened. — (J A common species about 

 buildings, fences, wet grounds, &c. St. smooth, branched, leafy, 1 to 2f high, 



