2^ rOLYGUNACE.K. Pulijyunum. 



3 inclies long, often in pairs : flowers and fruit nearly as in tlie last. — P. ani])hibhan, 

 var. terrestir, (iray, JMamuil, 41G, and others; not of Willdenow. P. amphibium, 

 var. (I) Muhkubtn/ii, Meisner, 1. c. IIG. 



In Washington Tcriiloiy and Oregon, and collectt'd in Culifoiiiiii (Bluomcr) but locality not 

 given— extending eastward to the Atlantic Coast and Texas. 



* * Sheaths and brads bi'istli/ cUlate or the sheaths sometimes foUaceouslij 



marijlned. 



-I- Sepals not jjunetate : style 2-eleft, and alcene somewhat flattened. 



10. P. Hartwrightii, Oray. Perennial, closely allied to the two preceding spe- 

 cies, growing u.siiaily in nnid, the ascending stems rooting at base and very leafy : 

 dilfering from the form of P. ambiginim, growing in like localities, by being more or 

 less rough-liairy, at least on the sheaths and bracts, the former ciliate and often with 

 abruptly spreading foliaceous bonlers ; leaves rather narrow, 2 to 7 inches long, on 

 very short petioles, adnate to the middle of the sheath. — Proc. Am. Acad. viii. 294. 



Plumas Co. (i//-s. M. E. P. Ames); Utah {JFatson, Ward); and eastward through the North- 

 ern States. It varies greatly in hirsuteness and in the characters of the sheath, and when grow- 

 ing in water the lower leaves are thick, smooth, and floating, a|)proaching P. amphibium too 

 closely. 



P. Peusicaria, Linn. Resembling P. nodosum, but sheaths and bracts ciliate ; leaves usually 

 marked by a dark spot near the middle ; sjjikes short, erect ; liowers .shortly jiedicelled ; style 

 '2-3-cleft, and akene sometimes triangular. —A very common species in the Atlantic States, in- 

 troduced from Europe ; rejjorted from Califoi-nia only in Bot. Beecluy. 



^ H_ Sepals conspkuouslif dotted and leaves 2^anctate: sti/le mostly 3-parted, and 

 akene trianyular : juice very aerld. 



17. P. acre, IIPK. Perennial, rooting and decuml)ent at base, 2 to 5 feet high, 

 branching, sniootli or somewhat scabrous with short apprcssed hairs : leaves lanceo- 

 late to linear-lanceolate, acuminate, attenuate to a very short petiole : sheaths and 

 the short bracts bristly ciliate : spikes loose and Jiliform, 1 to 3 inches long, erect 

 on long peduncles : liowers greenish white or purplish, a line long : stamens 8. — 

 l^ov. Gen. ii. 17'J ; Gi-ay, Manual, 41G. 



Common in the Atlantic States and ranging to Mexico ami South America ; collected in the 

 San Jose Valley (Prciccr), but perhaps introduced. 



P. HvDiioi'iPKi;, Linn., is an allied amuial species, with shorter acute or often obtuse leaves 

 and more nodding .sj.ikes ; .stamens 6 ; style more freipiently 2-i)arted, and akene conse<iuently 

 often compressed. —A Euro])ean si)ecies which also ranges across this continent northward ; found 

 in Washington Territory and perhnps in Northern California. 



§ 4. Glabrous alpine or subalplne herbaceous 2'ercnnlals, with thick creeping root- 

 stocks and slmjde stems: Jlowers In dense splke-llke racemes ; ]>frl(infh 

 colored, deeply i)-clcft, at length appressed to the triangular akene: stamens 

 f^,V'lfh filiform filaments: styles :\, long: leaves plnnately veined j petioles 

 not jointed : sheaths oblajnely truncate, naked, as well as the scarlous ovate 

 or lanceolate bracts. — Bistorta, Linn. 

 18. P. Bistorta, Linn. Stems usually a foot or two high : leaves few, the 

 radical ones on long petioles, oblong-lanceolate to linear, acute at each end, 2 to 8 

 inches long, the cauline much reduced, mostly obtuse at base and ses.sile ui)on the 

 sheath; the margin often slightly revolute : sheaths elongated: flowers 1^ to 2^ 

 lines long, rose-colored to white, on slender i>edicels, in very dense ovate to oblong 

 spikes h to 1.', inches long and usually long-pcnlunculate : bracts ovate, acuminate: 

 stamens and styles exserted : akene li lines long, smooth and shining. — Meisner, 

 DC. Prodr. xiv. 125. 



Throughout the northern hemisiihere ; fre(iuent in meadows and on stream-banks in the Sierra 

 Nevada at 6-10,000 feet altitude. 



