rOriLAK FLOHA. 



197 



to 6 

 .vary 



may 

 137). 



Calyx of :; (rarely 4) nearly siiiiilar scpalH, nil more or loss potnl-like. 



Stanu'iis 4 to 9 : akeiie generally small : cotyUdoiis narrow. {Poh/r/onum) KnotwkeD, 



Stamens 8 : styles 3 : akvnt triangular, sliapo.i like ;i becclmut, much longer thnn the 

 calyx ; cotyli-ilonH very hro^nl ami f(»Ulf(l in the mealy alh\imfii : loot annual : 

 h'Mves ncin ly iiallti-ril-sliai.ed : flowers, white, corymijeil, {Fa:i'>j)i'/rniii) *15li'K\viikaT. 

 Cnlyx of 6 sejmls, ami 



All alike and iretal-like (white) : stamens 9 : styles 3, ilihatm) •HurB.vUB. 



'J'hree outer ones herhaceousand siireadin;; : three inner larger, especially after llower- 

 ing, when they close over the trians^ular iikeiie ; llowers diu'-ious : leaves sour, 

 eared or halberd-shaped, i /.'«///(. r. J:,)(v/..j*.//<») SoKRKr„ 



Flowers i)erfect or polygamous : leaves hitter : coarse h.i lis. [Iliiiiif.r] Dock. 



Knot weed, f'olffjouum. 



* Flowers single or several together in the axils of the leaves, greenish or whitish : sheaths (stij)ules) 



cut-fringed or torn into narrow shreds. 



1. Common Knotwkkd, Kn<)T(;uas.s, or (!(M)sk<;I(As,s. Spreadinv; on tiie ground, small ; leavef^ 



sessile, lance-shaped or oblong, pale ; a variety has nearly upright stems and oblong or ov.al 

 leaves. The commonest weed in yards and waste places. P. aiirulikie, 



2. Slender K. Upright, somewhat blanched ; leaves linear, acute, sheaths fringed. Dry soil. 



/'. tf'nue, 

 * * Flowers in terminal heads, sjiikos, or racemes. 



+■ Not twining nor climbing, and leaves not heart-shaped nor arrow-shaped ; calyx petal-like and 



5-parted, except ill No. 10. 



3. OaiENTAi, K. or Pkixce's Fkatheh. Tall annual, 4' to 7' high ; leaves ovate ; si)ikes of rose. 



coloured flowers long and nodding; stamens 7 : akene flattish. Gardens. P. arinitnfe, 



4. Watku K. Stems filiating in water, or rooting in mud, or upright ; leaves l.iiice-sliaped o\ 



oblong ; spike thick and short ; flowers rose-red ; stamens 5 ; styles 2. /'. (tmfiiiUiiinn, 



5. Pennsylvania K. Stem upright, T to 3' high ; leaves lance-shaiied ; spike oVdong, thick, erect, 



its peduncle beset with club-shaped bristles or glands ; flowers rose-colouretl ; stamens 8 ; akene 

 flat. Moist ground. P. J'ltniKi/lrdnicum. 



6. Lady's-Thcmm K. Stems, &c., like tlie last and next, but no bristles on the peduncle; loaves 



with a daiker spot on tiie upper side ; spike sliort and thick, erect; flowers greenish-purple ; 

 stamens 6. Very common in waste i)laces. /'. Persivuria. 



7. Smaktweei) or "WATKli-rK.i'i'K.u K. Upright, annual, i'' or 2' high, very acrid and biting to the 



taste ; leaves and also the greenish sepals marked with fine transparent dots ; spikes short but 

 loose, drooping ; akene flattisli or bluntly triangular. JMoist ground, common in waste places, 

 yards, and near dwellings. P. H ;idro}i\pe,\ 



8. Wild Smautweeo K. Upright, 1'' to 3° high from a perennial root, biting like the last, and th« 



leaves dotted ; spikes very slender, erect, whitisli or flesh-colour ; stamens 8 ; styles 3 ; akeut 

 sharply triangular. Wet places. P. aci'e, 



9. Mild Wateii-I'EPI'KH K. Upright. 1^ to 3° high ; often creei>iiig at the base and rooting in water ; 



leaves roughish, not biting, narrowly lance-shaped ; spikes slender, erect, rose-colour ; stamens 

 8 ; style 3-cleft at the top ; akene sharply triangular. Shallow water. P. Iii/dropijiei'f'ulcs. 



10. Virginia K. Stem 2° to 4" high, angled; leaves large, ovate or lancoovate, taper-pointed; 



