380 POLYGONACEAE 
often acuminate at the apex, ciliate, more or less papillose, undulate or slightly crisped, 
punctate, containing a very acrid juice: ocreae 0.5-1 cm. long, fringed with long bristles, 
usually enlarged about the bases, often bearing one or two flowers within: racemes linear, 
2-6 cm. long, drooping, much interrupted : ocreolae funnelform, 1.5-2 mm. long : slightly 
oblique, fringed with a few short bristles: calyx greenish, 2.5-3 mm. long: sepals rather 
narrowly oblong, obtusish, glandular: stamens 4 or sometimes 6: achenes lenticular, 
biconvex, slightly gibbous, or 3-angled, 3 mm. long, broadly oblong or ovoid, sometimes 
orbicular or even broader than high, short-tipped, dark brown, strongly granular and dull. 
[Polygonum Hydropiper L.] 
Common in moist or waste places, almost throughout North America, Naturalized from Europe 
southward and eastward, said to be native in the north and west. WATER PEPPER. 
18. Persicaria orientalis (L.) Vilm. Annual, large, more or less hispid. Stem 
erect, 4-25 dm. tall, becoming woody below: leaf-blades ovate or broadly oblong, 6-25 
em. long, acuminate, varying from acute to cordate at the base, ciliate, hispidulous on the 
midrib and its lateral branches on both surfaces ; petioles 2-8 cm. long, slightly winged: 
ocreae 1-3 em. long, with a spreading border at the summit,'ciliate : racemes varying from 
oblong to linear, 3-10 cm. long, drooping or sometimes suberect, often slightly interrupted 
near the base: ocreolae funnelform, 3-5 mm. long, very oblique, ciliate: calyx dark rose- 
colored, 4-4.5 mm. long : stamens 7 : achenes lenticular, 3 mm. long, orbicular or broader 
than high, thickened laterally about the base, biconcave, minutely granular and rather dull. 
[ Polygonum orientale L. ] 
In waste places, generally. Naturalized from India. Summer and fall. PRINCE’s FEATHER. 
9. FAGOPYRUM Gaertn. 
Annual caulescent smooth and usually glabrous herbs. Leaves alternate: blades 
entire, hastate or cordate: ocreae oblique, entire. Flowers perfect, white or whitish, 
several together on slender pedicels subtended by an ocreola. Racemes in cluster-like 
cymes or corymbs. Calyx corolloid, persistent and unchanged in fruit. Sepals about equal. 
Stamens 8: filaments filiform, glabrous. Ovary 3-angled: styles 3: stigmas capitate. 
Ovule erect. Achene 3-angled,its angles slightly margined or crested, its faces transversely 
striate. Embryo dividing the mealy endosperm by an S-shaped curve. 
1. Pagopyrum Fagopyrum (L.) Karst. Rather fleshy when young. Stem 1-9 dm. 
tall, erect, simple or branched, with a little pubescence about the nodes: leaf-blades 
hastate, 2.5-8 cm. long, cordate, petioled, abruptly narrowed above the middle : ocreae 
brittle and fugacious: racemes many-flowered, erect or inclined to droop, continuing to 
flower after fruit is produced: calyx white or whitish : pedicel as long as the calyx, one- 
half as long as the achene or shorter : achenes broadly ovoid, acute, 5 mm. long, the faces 
pinnately-striate when mature, and slightly variegated, the angles acute, entire. 
In waste places, about cultivated fields and along railroads, more or less persistent. Adventive 
from eastern Europe and western Asia. Summer. BUCKWHEAT. 
10. TRACAULON Raf. 
Annual or sometimes perennial prickle-armed herbs, with reclining-climbing 4-angled 
stems. Leaves alternate: blades truncate, hastate or cordate, membranous, the petiole, 
midrib and principal nerves armed with small recurved prickles. Ocreae oblique, finely 
nerved, variously roughened about the base. Flowers in terminal and axillary spike- 
like racemes, these usually somewhat interrupted, or in capitate clusters. Sepals somewhat 
colored, 4-5, neither keeled nor winged, enveloping the achene. Stamens varying from 5 
to 8, included : filaments not dilated. Styles 2 or 3, partially united, included. Achenes 
lenticular or 3-angled, variously colored, strongly biconvex or three-angled, smooth and 
shining. Endosperm horny. Cotyledons accumbent. The plants flower in the summer 
and fall, or earlier in the extreme south. TEAR-THUMB. 
Leaf-blades sagittate or subsagittate: achenes 3-angled. 
Inflorescence dichotomous : leaf-blades sessile or nearly so : achenes blunt-angled. pon 
1. T. Beyrichianum. 
Inflorescence not dichotomous : leaf-blades manifestly petioled : achenes sharp-angled. _ 
2. T. sagittatum. 
Leaf-blades hastate: achenes lenticular. 3. T. arifolium. 
1. Tracaulon Beyrichiànum (Cham. & Schlecht.) Small. Perennial, somewhat wiry. 
Stem 5-10 dm. long, reclining, dichotomously branched, slightly enlarged at the nodes, 
