136 POLYGONE^. 



short petiole, cleft to the middle, or more deeply, into a lacerate and 

 somewhat curled fringe : fi. several, sessile, less than a line long : achene 

 chestnut-brown, smooth and shining. — Subalpine in the vicinity of the 

 Yosemite, Parry; but it is represented in niimbers 6355 and 6451 of the 

 State Survey, and may have been referred to P. imbricalum. It is a link 

 connecting Duravia with true Polygonum. 



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

 cal, oblique or truncate; f. in dense spikes or loose cyrnelets; stamens 

 4 — 8, all the filaments filifonn ; styles deciduous; cotyledons accumhent. 

 4— Stems usually branching, leafy, the spikes often panicled; styles short, 

 often only 2 and the achene lenticular. — Old genus Persicaria. 

 ++ Weedy annuals of fields and gardens. 



15. P. nodosum, Pers. Syn. i. 440 (1805). 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 

 piirple-dotted throughout : leaves lanceolate, 2—5 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 cultivated lands, preferring moist places. July — Oct. 



16. P. Persicaria, Linn. Sp. PI. i. 361 (1753). Persicaria maculosa, 

 S. F, Gray, Nat. Arr. ii. 269 (1821). Much like the last but the sheaths 

 and bracts conspicuously ciliate : leaves less acuminate, subsessile : 

 spikes shorter and erect : fl. rose-color : achenes often triquetrous. — 

 Apparently uncommon in California, but reported in the Botany of 

 Beechey's Voyage as here, and found in Humboldt Co. more recently, 

 Rattan, Chesnul tfr Drew. Both this and the last are natives of Europe 

 and Asia. It is impossible to say whether with us they are indigenous or 

 introduced weeds. July — Oct. 



■M- -M- Perennials, either aquatic or of iret places. 



17. P. acre, HBK. Nov. Gen. ii. 179 (1817). Decumbent, rooting at 

 the lower joints, 2 — 5 ft. high ; herbage light green, pellucid-punctate 

 and acrid, glabrous or a little scabrous : leaves lanceolate, acuminate, 

 short-petioled ; sheaths bristly-ciliate : spikes narrow and lax, 1 — 3 in. 

 long, erect : sepals greenish and glandular-dotted, 1 line long : stamens 

 8 : achene commonly triquetrous. — Very common in marshy fjlaces, 

 along streamlets, etc. June — Nov. 



18. P. Hartwrightii, Gray, Proc. Am. Acad. viii. 294 (1870). Stems 

 stout and simple, rooting at the decumbent base, above equably leafy to 

 the summit ; herbage more or less strigose-hirsute : leaves broadly 

 lanceolate, acute, 2—7 in. long, on very short petioles ; stipules with an 



