I 12 
POLYGONUM 
Section III. *ECHINOCA UL ON 
Echinocaulon Meisner in Wallich Plant. Asiat. Par. iii, 58 (1832); Meisner in DC. Prodr. xiv, 84 et 
13 1 (1856); Dammer in Engler und Prantl Pflanzenfam. iii, pt. i a, 28 (1893) as a subsection. 
For characters, see page 109. Only British species : — *P. sagittatum. 
4. ^POLYGONUM SAGITTATUM. American Tear-thumb. Plate 119 
Polygonum sagittatum L. Sp. PI. 363 (1753)!; Robinson and Fernald in Gray New Man. 362 (1908). 
leones : — Camb. Brit. FI. ii. Plate 119. {a) Flowering shoot, (b) Portion of leaf (enlarged). ( c ) Ochrea 
(enlarged) cut open and laid flat. ( d ) Portions of stem (enlarged). ( e ) Flower (enlarged), (f) Pistil (enlarged). 
(g) Achenes (one enlarged). Co. Kerry (G. C. D.). 
Annual. Stem 4-angled. Petioles about a fifth as long as the laminae. Laminae narrowly 
sagittate, margin more or less bristly, midrib prickly underneath. Peduncles short, not bristly. 
Stamens usually 8. Stigmas 3. Achenes trigonous. 
First recorded by Mr R. W. Scully (in Bot. Exch. Club Rep. for 1906, 26 (1907)) as P. arifolium L. The name was 
corrected later {op. cit., p. 384). P. arifolium has longer petioles, broader laminae, and larger achenes than P. sagittatum , 
and peduncles which are glandular-bristly, and only 6 stamens. 
Abundant in the stony bed of a small stream, just above tidal influence, at Castle Cove, Kenmare Bay, 
co. Kerry, Ireland;' abundant also in a small damp hollow, a mile further north, at about 60m. above sea-level. 
Said to have been accidentally introduced into the first locality, owing to the wreck on the adjacent coast of a 
small vessel laden with Indian corn {Zea mats), and to have been carried to the second by cattle ; now quite 
established (see Bot. Exch. Club Report for 1906, ii, 241—2 (1907)). 
Indigenous in North America (as var. americanum Meisner in DC. Prodr. xiv, 132 (1856)) and in central 
Asia (as var. sibiricum Meisner loc. cit.). 
Section IV. BIS TORT A 
Bistorta [Tournefort Inst. 51 1, t. 291 (1719) as a genus] DC. FI. France iii, 364 (1815); Don Prodr. 
FI. Nepal. 69 (1825); Meisner Polyg. Monogr. 43 et 50 (1826); in DC. Prodr. xiv, 101 (1856); Dammer in 
Engler und Prantl Pflanzenfam. iii, pt. i a, 27 (1893) as a subsection. 
For characters, see page 109. 
British species oe Bistorta 
5. P. bistorta (see below). Laminae decurrent on to the petiole. Spikes stout. 
6. P. viviparum (p. 1 1 3). Laminae not decurrent. Spikes slender. 
5. POLYGONUM BISTORTA. Bistort or Snake-root. Plate 120 
Bistorta major Gerard Herb. 222 (1597) including B. latifolia\ Ray Syn. ed. 3, 147 (i7 2 4)- 
Polygonum bistorta L. Sp. PI. 360 (1753)!; Syme Eng. Bot. viii, 78 (1868); Rouy FI. France xii, 
95 (1910). 
leones: — Curtis FI. Lond. i, t. 71; Smith Eng. Bot. t. 509; FI. Dan. t. 421; Beck in Reichenbach Icon. 
xxiv, t. 219, as P. bistorta. 
Camb. Brit. FI. ii. Plate 120. ( a ) Flowering scape, {b) Lower leaf, (c) Portion of plant, with rhizome and 
roots, (d) Ochrea (enlarged). ( e ) Flower (enlarged). (/) Pistil (enlarged). West Riding of Yorkshire (J. N.). 
Exsiccata : — Billot, 2357, 2357 bis; Bourgeau, 65; Fries, xi, 52; Reichenbach, 480. 
Perennial. Rhizome stout, contorted, creeping. Aerial stem erect, 2 — 5 dm. high, slender, 
unbranched. Petiole long (10 — 30 cm.). Laminae of the ground-leaves oval-oblong to oblong, decurrent 
below, obtuse to subacute at the apex, about 7*5 — i5’o cm. long and 4 — 7 broad, glaucous underneath ; 
of the stem-leaves subsessile, acute. Spike about 3 '8 — 5'o cm. long and 1*5 broad, dense-flowered, 
cylindrical. Flowers honeyed, protandrous ; June, and a second display in September. Perianth 
about 4mm. in diameter, pink, rarely white; segments 5, rounded. Stamens 8, exserted. Anthers 
small. Achenes trigonous, angles prominent, brown, shining. 
