377 
++ Sheaths and bracts bristly ciliate or sheaths foliaceously margined. 
++ Sepals not punctate: style 2-cleft, and achene somewhat flattened (except in No. 14). 
12. P. orientale L. (PRINCE’s FEATHER.) Tall (9 to 15 dm. high) branching soft- 
hairy annual: leaves ovate or oblong, pointed, distinctly petioled: sheaths ciliate 
or often with an abrupt spreading border: flowers large, bright rose-purple, in 
densely cylindrical nodding spikes: stamens 7,—Escaped from gardens. 
13. P. Persicaria L. (Lapy’s rHumB.) Nearly smooth and glabrous, 3 to 5 dm. 
high: sheaths more or less bristly ciliate; leaves lanceolate, pointed, roughish, often 
marked with a dark triangular or lunate spot near the middle: spikes ovoid or 
oblong, dense, erect, on smooth (or at least not glandular) peduncles: stamens 
mostly 6; styles half 2 or 3-cleft: achene gibbous-flattened or sometimes triangular, 
smooth and shining.—Wet places, from the Limpia to central Texas, 
14. P. persicarioides HBK. Stem glabrous: sheaths ciliolate: leaves subsessile, 
lanceolate, 8 to 1lem. long, glabrous except margins and veins: spikes racemose- 
paniculate, densely flowered, linear-oblong, attenuate (2.5 to 3 em. long) upon gla- 
brous peduncles: bracts subimbricate, the lower short ciliate: pedicels finally 
exserted: calyx 5-parted, nervelessand glandless; stamens 7 or 8: style 2 or 3-cleft, 
subincluded: achene small (hardly 2mm. long), biconvex or 3-angled, very smooth 
and shining.—Extending from Industry (Austin County) to central Mexico, 
++++ Sepals conspicuously dotted and leaves punctate (except No. 16), with acrid juice: style 
mostly 3-parted and achene 3-angular: sheaths bristly Sringed. 
15, P. setaceum Baldw. Erect perennial (6 to 9 dm. high), sparingly branched, 
smooth below, the upper portion (as well as the lanceolate leaves) roughened with 
appressed hairs: leaves 5 to 10cm. long; stipules appressed-hirsute, copiously fringed 
with long bristles: spikes filiform (2.5 to 5.em. long), in pairs, loosely flowered: flowers 
white, glandless: stamens 8.—Extending from the Gulf States into Texas. 
16. P. hydropiperoides Michx. (MILD WATER-PEPPER). Perennial, not acrid: 
stem smooth (3 to 9 dm. high), branching, the narrow sheaths hairy: leaves narrowly 
lanceolate, sometimes oblong: spikes erect, slender, sometimes filiform, often inter- 
rupted at base (2.5 to 6.5em.long): flowers small, flesh-colored or nearly white: sepals 
not dotted: stamens 8: achene sharply 3-angled, smooth and shining.—Wet places 
and in shallow waters, central and southern Texas. 
17. P. Hydropiper L. (COMMON SMARTWEEd or WATER-PEPPER). Annual, 3 to 6 
dm. high, smooth: leaves narrowly to linearanceolate : spikes nodding, usually short 
or interrupted: flowers mostly greenish: stamens 6: styles 2 or 3-parted: achenes 
dull, minutely striate. —Moist and wet grounds. Apparently introduced in the east, 
and south westward as far as northwest Texas and Arizona; but indigenous north- 
ward and westward. 
18. P. punctatum EJ], (WATER SMARTWEED). Perennial, nearly smooth: stems 
rooting at the decumbent base, 6 to 15 dm, long, leaves 5 to 10 dm. long, longer than the 
last, taper-pointed: spikes erect: flowers whitish, sometimes flesh-colored: stamens 
8: styles mostly 3-parted: aclhene smooth and shining (P. acre HBK., not Lam.).— 
Wet places from El Paso to central and southern Texas. 
*** Glabrous alpine perennials, with ereeping rootstocks and simple stems: flowers in a 
spike-like raceme: calyx colored, deeply 5-cleft: stamens 8: styles 3, long. 
19, P. bistortoides Pursh. Stems 3 to 6 dm. high: leaves few, the radical ones on 
long petioles, oblong-lanceolate to linear, acute at each end: the cauline much re- 
duced, mostly obtuse at base and sessile upon the sheaths, the margin often slightly 
revolute: flowers rose-colored to white, on slender pedicels, in very dense ovate to 
oblong spikes, and usually long-pedunculate: stamens and styles exserted: achene 
smooth and shining. (2, Bistorta, var. oblongifolium Meisn.)—Meadows and stream- 
banks in the mountains of western Texas. 
