410 I'ULYUUNACE.E. (lUCKWIlKAT I'AMILV.) 



t'sd'apeJ troiii i.uhiv;itiou. Juao-Sej)t. — Stem IJ-'-S^ l''n''- •'^I'ikes 2'-3' 



l,.ng. 



§ 'J. ri;KsKAiUA. — Fluwfrs in closet if-bracted Sjiiki'S : stamens 4-8: styles 



:i -.'!,«;• 2 - li-ciij't : arlttnium 3-<ini/lc(l or lenticuliir : cotijltdons uccambcnt: 



albumen Itornj : sheaths ci/lindrical, trtinrute. 



» ^heaths nuLetl : sti/le 2-fleJi or :>]Hirli(l : acheniu in lenticular. 



2. P. incarnatum, Ell. Stem smoutli below, the Kummit of the 

 braiahes, |i((liiii( Ics, ami calvx spriiikkHl willi glaudiilur dots; leaves lance- 

 olate, luii;^-aeiniiiiiate, petioleil; spikes raeemed, linear, uoddiug; bracts 

 loiif^er thau the pedicels; Howers small, llesh-color; stameusG; st\ le 2-parted ; 

 aeheiiium ovate, with the sides comave. — I'ouds, ditches, etc., South Caro- 

 lina, and westward. July-Oct. (l) — Stem 2° -3^ liigh. Leaves 6'-8 

 long. Sjiikes 1'- 2' long. 



3. P. densiflorum, Meisner. Stem stout, smooth, branching above; 

 leaves lanceolate or oblong-lanceolate, acuminate ; spikes racemed or some- 

 what ])anick'd, linear, erect, dense-Howered, the peduncles minutely glandular ; 

 bracts shorter than the pedicels; .stamens mostly 6; style 2-cleft; acheniuin 

 round-ovate, black and sliining, with the sides convex. — Jluddy banks, 

 Florida, and westward. Sept. -Oct. (l)— Stem 3° -4° high. Leaves 6'- 

 10' long. Spikes 2' -4' long. Flowers white. 



4. P. Muhlenbergii, Watson. Stem stout, pubescent above ; leaves 

 3'- 6' long, broadly lanceolate, acuminate ; spikes erect, racemose or in pairs, 

 linear-cylindrical, close-flowered, l'-2' long; flowers large, rose-colored; 

 achenia comj)ressed. — Muddy banks, Florida, and northward. 



5. P. Pennsylvanicum, L. Stem smooth below, the l)ranches and 

 peduncles glandular; leaxos sliort-petioled, lanceolate ; sjjikes erect, t)l)long, 

 obtuse, close-flowered ; flowers large, rose-color ; stamens mostly 8 ; style 2- 

 cleft ; achenium orbicular, with the sides concave — Wet places. July - Sept. 

 ® — Stem 1^-3' high. Leaves 2' -4' long. Spikes I'-U' long. 



* * Sheaths frinfjed with bristli/ hairs: achenia 3-an(jled, or {in Nos. 6 and 8) 

 sometimes lentirii/ar : stantens mosti i] 8. 



C. P. Persicaria, L. Stem smooth, branching from the base, erect or 

 diffu.se; leaves lance(jlate or oblong, sheaths short, nearly smooth, fringed 

 with a few short bristles ; spikes short, oblong ; flowers rose-color; stamens 

 6 - 7 ; achenium lenticular or 3-angled, smooth and shining. — Waste places. 

 Introduced. July. (T) — Stem 1°- H° high. Leaves 2' -4' long, often with 

 a dark triangular spot in the middle. Spikes i'- I' long. 



7. P. acre, Kunth. Stem slender, smooth, creeping at the base ; leaves 

 lanceolate, and, like the white calyx, dotted with pellucid glands; sheaths 

 smoothish, long-fringeil at the throat; spikes 1-3, filiform, loose-flowered; 

 stamens 8 ; style 3-parted ; achenium 3 angled. (P. punctatum. Ell.) — Ditches 

 and margins of ponds, Florida, and northward. July - Sej)t. 2/ — Stem 

 1° -.3° long. Leaves 2' -4' long, very acrid. Spikes 2'- 3' long. 



8. P. Hydropiper, L. (Commov Smartweeo.) Annual, smooth ; 

 leaves lanceolate, jtunctate, acrid; spikes slender, interruj)tcd, nodding 



