POPULAR FLORA, 193 
Calyx of 5 (rarely 4) nearly similar sepals, all more or less petal-like. 
Stamens 4 to 9: akene generally small:. cotyledons narrow, (Polygonwm) KnotwEEp. 
Stamens §: styles 3: akene triangular, shaped like a beechnut, much longer than the 
calyx: cotyledons very broad and folded in the mealy albumen: root annual: 
leaves nearly halberd-shaped: flowers white, corymbed, (Fagopyrum) *BuckwHeEat. 
Calyx of 6 sepals, and 
All alike and petal-like (white): stamens 9: styles 3, (Rheum) *RHUBARB. 
Three outer ones herbaceous and spreading: three inner larger, especially after flow- 
ering, when they close over the triangular akene: flowers dicecious: leaves ‘ 
sour, eared or halberd-shaped, (Rumex, § Acetosclla) SorREL. 
Flowers perfect or polygamous: leaves bitter: coarse herbs, (Rumez) Dock. 
Knotweed. Polygonum. 
® Flowers single or several together in the axils of the leaves, greenish or whitish: sheaths (stipules) 
cut-fringed or torn into narrow shreds. 
1. Common Kxorwerp, Kyorerass, or Goosecrass. Spreading‘on the pround, small; leaves 
sessile, lance-shaped or oblong, pale; a variety has nearly upright stems and oblong or oval leaves. 
The commonest weed in yards and waste places. P. aviculare. 
2. SLENDER K. Upright, somewhat branched; leaves linear, acute, sheaths fringed. Dry soil. P. ténue. 
* * Flowers in terminal heads, spikes, or racemes. 
+ Not twining nor climbing, and leaves not heart-shaped nor arrow-shaped: calyx petal-like and 
5-parted, except in No. 10. 
3. OrrenTaL K. or Prince’s Fearuer. Tall annual, 4° to 7° high; leaves ovate; spikes of rose- 
colored flowers long and nodding; stamens 7; akene flattish. Gardens. P, orientale. 
4. Warer K. Stems floating j in water, or rooting in mud, or upright; leaves lance-shaped or oblong; 
spike thick and short; flowers rose-red; stamens 5; styles 2. P. amphibium. 
5. PENNSYLVANIA K. Stem upright, 1° to 8° high; leaves lance-shaped; spike oblong, thick, erect, 
its peduncle beset with club-shaped bristles.or glands; flowers rose-colored; stamens 8; akene 
flat. Moist ground. P. Pennsylvdnicum. 
6. Lapy’s-Tnums K. Stems, &c. like the last and next, but no bristles on the peduncle; leaves with 
a darker spot on the upper side; spike short and thick, erect; flowers greenish-purple; stamens 
6. Very common in waste places. P. Persicaria. 
7. SMARTWEED or WATER-PEPPER K. Upright, annual, 1° 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 flattish or bluntly triangular. Moist ground, common in waste places, 
yards, and near dwellings. P. Hydrop\per. 
8 Witp SmartweErD K. Upright, 1° to 8° high from a perennial root, biting like the last, and the. 
leaves dotted; spikes very slender, erect, whitish or flesh-color; stamens 8; styles 3; akene sharply, 
triangular. Wet, places. P. acre. 
9. Miwp Water-Perrer K. Upright, 1° to 8° high; often creeping at the base and rooting in water; 
leaves roughish, not biting, narrowly lance-shaped; spikes slender, erect, rose-color; stamens 8; 
style 3-cleft at the top; akene sharply triangular. Shallow water. P. hydropiper ‘ordes. 
10. VirointaA K. Stem 2° to 4° high, angled; leaves large, ovate or lance-ovate, taper- pointed ; flow- 
