122 
POLYGONUM 
Exsiccata : — Fries, iv, 75, as P. minus ; iv, 76, as P. mite subsp. laxiflorum ; vii, 53, as P. mite var.; xi, 53, 
as P. mite subsp. s trictum; Fiori et Beguinot, ii, 1265, as P. minus ; v. Heurck, i, 18, as P. minus-, Reichenbach, 
285, as P. minus ; Thielens et Devos, iv, 333, as P. mite\ Wirtgen, viii, 400, as P. mite var. longiflorum ; 
Herb. FI. Ingric. vii, 543 (partim), as P. minus ; “herb. Miller” (in Herb. Mus. Brit.) as P. persicaria. 
Habit approaching that of P. laxiflorum. Stem 2*5 to 8'odm. Ochreae ciliate with long hairs. 
Laminae larger and relatively broader than in var. subcontiguum. Spikes larger and usually more 
interrupted, rather pendulous. Perianth rather larger. Ackenes rather larger. 
From the Channel Isles, Isle of Wight, Dorset, and Sussex northwards to Carnarvonshire, Cheshire, and the 
North Riding of Yorkshire; chiefly in eastern England; Ireland — counties Cork, Meath, Monaghan, Leitrim, 
Cavan, Down, Mayo. 
Europe. 
(1 b ) P. minus var. subcontiguum Wallich PI. Asiat. Par. iii, 57 (1832); Rouy Ft. France xii, 102 (1910); 
P. mite subsp. strictum var. pusillum Fries Ft. Suec. Mant. ii, 32 (1839). 
leones: — Curtis Ft. Lond. i, t. 77, as P. minus', Smith Eng. Bot. t. 1043, as P. minus ; FI. Dan. t. 2230, 
as P. strictum var. pusillum ; Beck in Reichenbach Icon. t. 213, fig. 2 — 6, as P. minus. 
Camb. Brit. Ft. ii. Plate 129. (a) Flowering branches. ( b ) Flowering branches of f. aquaticum. (c) Ochreae 
(enlarged), (d) Pistils (enlarged), (e) Achenes (3 enlarged). Middlesex (W. H. B.), and (b) Cambridgeshire 
(C. E. M.). 
Exsiccata: — Billot, 2358, as P. minus', Thielens et Devos, iv, 332, as P. minus', Wirtgen, xi, 627, as P. 
minus forma; Herb. FI. Ingric. vii, 543 (partim), as P. minus. 
Stem more slender, 1*5 — 3'o dm. Ochreae less inflated, ciliate. Laminae lanceolate-acuminate, 
gradually attenuate below the middle, ciliolate, about 2^5 — 5'ocm. long. Spikes shorter, less inclined, 
and less interrupted than in var. elatum. Perianth and achenes rather smaller. 
(y8) var. subcontiguum forma aquaticum comb. nov. ; P. minus var. erectum Rouy FI. France xii, 103 (1910). 
Stem erect, taller, subsimple. Laminae longer and narrower. 
This is the water-form of the species. In the river Ouse, Cambridgeshire, and doubtless elsewhere. 
France and doubtless elsewhere. 
Dorset and Sussex to Cumberland ; Ireland — counties Down, Roscommon, Queen’s county, and Cavan. 
Grenier and Godron (FI. France iii, 49 (1855)) state that P. mmus is a plant of siliceous soils; and Praeger ( Irish 
Top. Bot. 272 (1901)) also describes its stations as being “off the limestone.” However, these statements (which we in no 
way doubt) are not applicable to the plant as it occurs in East Anglia. 
Margins and banks of ponds, lakes, and ditches ; from the Channel Isles, Cornwall, Kent, 
northwards to Dumbartonshire and Aberdeenshire; local in Wales, the north of England, central 
and eastern Scotland, and Ireland. 
Europe (northwards to central Scandinavia and Finland) ; Asia ; Malaysia ; Chile. 
P. laxiflorum x minus (p. 120); P. hydropiper x minus (p. 1 1 9). 
P. 'minus x pevsicCLViCL A. Braun in Flora vii, 359 (1824) ; Reichenbach FI. Germ. Excurs. ii, 571 (1830) ; 
Grenier et Godron FI. France iii, 50 (1855); Giirke PI. Europ. ii, 1 19 (1897); Rouy FI. France xii, 106 (1910); 
leones : — FI. Dan. t. 2959, as P. minori-persicaria. 
Exsiccata: — Billot, 1320, as P. dubio-persicaria. 
Stem, erect or decumbent, longer than P. minus, even than P. minus var. elatum, branched. Ochreae 
ciliate. Laminae lanceolate-acute. Spikes cylindrical, narrower than in P. persicaria , a little interrupted 
towards the base, larger than in P. minus. Perianth pink, smaller than in P. persicaria. Stamens 6. 
Achenes rarely formed, about 3 mm. long. 
Hampshire, Sussex, Berkshire. 
Denmark, Belgium, France, Germany, northern Italy. 
Section VI. CENTINODE 
Centinode DC. FI. France iii, 368 (1815); Avicularia Meisner Monogr. Polyg. Prodr. 43 et 65 (1826); 
Dammer in Engler und Prantl Pflanzenfam. iii, pt. i a, 2 7 (1893). [ Polygonum Tournefort Inst. 510 t. 290 (1719) 
as a genus.] 
For characters, see page 109. 
