POLYGONE^. 41 



in the axils of short leafy branchlets, each involucrate with a sheath-like 

 scarious bract on the joint of the short pedicel: sepals 1^ lines long, 

 rose-color or white, slightly spreading. Plentiful near the Soda Springs 

 above Napa; also in Sonoma Co. Aug. Oct. 



-H- Annuals, with striate stems andless conspicuous sheaths; branches 

 leafy to the summit, floriferous throughout. 



3. P. AVIOULAKE, L. Stoutish, much branched, prostrate, the branches 

 13 ft. long: herbage glabrous, bluish-green: leaves oblong or lanceolate, 

 acutish, % 2} in. long: fl. on very short pedicels: sepals 1 line long, 

 green, with white or rose-colored margin: achene broadly ovate, 1 line 

 long or less, dull black and minutely granular. A prevalent weed in 

 summer fields and vineyards. April Oct. 



4. P. coarctatum, Dougl. Erect, freely branching, the herbage 

 more or less scabro-puberulent throughout: leaves firm in texture, acute: 

 fl. spicate-crowded and on erect pedicels : sepals rose-color or white with 

 only a broad midvein of green : achenes very minutely punctate toward 

 the apex. Petrified Forest, Sonoma Co. July Sept. 



* * Leaves not jointed with the petiole, striately 3-nerved; sheaths 2-lobed 



orfimbriate; stamens 8, the inner 3 scarcely dilated. 



5. P. Californicum, Meisn. Erect, slender, 36 in. high, panicled- 

 spicate, the stem and branches glabrous, dark brown: leaves rigid, linear 

 or filiform, % \% in. long, pungently acute : spikes very slender, elon- 

 gated, the subulate bracts 1 2 lines long; sheaths 1 line long, deeply 

 lacerate-f ringed, nearly equalling the pale rose-colored flowers: achene 

 narrow, slightly exposed; styles slightly divergent. Valleys and dry 

 hills of the interior, near Napa, etc. July Sept. 



* * * Leaves not jointed, more ample, pinnately veined; sheaths cylin- 



drical, oblique or truncate; fl. in dense spikes or loose cymelets; 



stamens 48, all the filaments filiform; styles deciduous, 



often only 2 and the achene lenticular. 



} Weedy annuals of fields and gardens. 



6. P. nodosum, Pers. Stoutish, erect or ascending, 1 4 ft. high, 

 freely branching, glabrous except the rough glandular peduncles, and 

 scabrous leaf-margins and veins beneath; stem often purple-dotted 

 throughout: leaves lanceolate, 25 in. long, acuminate, short-petioled ; 

 sheaths naked in age, glandular-ciliolate when young: spikes linear, 

 usually drooping, 1 in. long or more: fl. white or pale rose, 1 line long: 

 stamens 6: styles 2: achene lenticular, ovate. Very common in culti- 

 vated lands, preferring moist places. July Oct. 



