134 
RUMEX 
Camb. Brit. FI. ii. Plate 141. (a) Flowering shoot. (6) Stem-leaf (on left) and ground-leaf (on right). 
(c) The three persistent perianth-segments of a single fruit, (d) Flowers (two enlarged), (e) Fruiting segment 
(enlarged). Switzerland (a, b, d) (E. W. H.) and Westmorland (c, e) (C. E. M.). 
Exsiccata : — Reichenbach, 868 ; Tausch. 
Perennial. Rhizome very stout, branches thick. Stem 3—8 dm. high, stout, branches short. Petioles 
of the ground-leaves long, stout. Laminae of the 
ground-leaves suborbicular-cordate. Inflorescence 
only a little leafy, branches suberect, whorls almost 
confluent. Pedicels much longer than the fruiting 
segments, jointed much below the middle. Flowers 
dioecious or polygamous ; June and July, the earliest 
member of the section to flower. Fruiting seg- 
ments suborbicular-cordate, entire or nearly so, 
strongly reticulate, 1 bearing a small or very small 
linear tubercle, about 5 mm. long and 4 broad. 
As in the Alps, this is with us a nitrophilous species, 
occurring in fresh, wet places, near habitations, cow-sheds, and 
“lagers.” The rhizome was formerly used as a simple and the 
leaves as a pot-herb ; and consequently many British systematists 
have regarded the plant as a mere relic of cultivation in all its 
stations in this country. On the other hand, Hooker [op. cit.) 
thought the plant was indigenous ; and its definitely northern 
distribution in hilly districts alone tends to confirm this view. 
By' stream-sides in hilly districts, usually near habita- 
tions, local and rather rare. Staffordshire, Derbyshire, 
West Riding of Yorkshire, Westmorland, Dumbartonshire, 
Fifeshire, Clackmannanshire, Perthshire, Aberdeenshire, 
Elginshire; not recorded for Wales or Ireland. 
Mountainous districts in central and southern Europe ; 
Asia Minor ; Caucasus. Ascends to 2640 m. in Switzer- 
land. 
Map 23. Distribution of t Rumex alpinus in 
Great Britain 
Series ii. Hydrolapatha 
Hydrolapatha nobis. 
For characters, see page 133. Only British species: — R. hydro lap at hum. 
5. RUMEX HYDROLAPATHUM. Great Water Dock. Plate 142 
Hydrolapathum magnum Gerard Herb. 312 (1597); Lap at hum maximum aquaticum sive hydrolapathum Ray 
Syn. ed. 3, 140 (1724). 
Rumex hydrolapathum Hudson FI. Angl. ed. 2, 154 (1778); Smith Eng. FI. ii, 195 (1824)!; Syme 
Eng. Bot. viii, 51 (1868); Rouy FI. France xii, 74 (1910); Ascherson und Graebner Syn. iv, 728 (1912); 
R. britannicus Hudson FI. Angl. 135 (1762) non L. Sp. Pl.\ R. aquaticus Miller Gard. Diet. ed. 8, no. 3 (1768); 
Smith FI. Brit. 394 (1800); Fries FI. Suec. 109 (1828)!; non L.; R. maximus Gmelin FI. Bad. ii, 99 (1806) 
non Schreber. 
leones : — Camb. Brit. FI. ii. Plate 142. (a) Flowering branches of var. vulgaris. ( b ) Leaves of var. 
vulgaris, [c) Basal leaf of var. vulgaris, (d) Fruiting segments (one enlarged) of var. vulgaris. Huntingdon- 
shire (E. W. H.). [e) Fruiting segments (two enlarged) of var. latifolius. 
A large, perennial, glaucous herb. Rhizomes thick, with numerous stout rootlets which are said 
to function as aerating organs. Stem about i - 5 or nearly 2’o m. high, strict, robust, branched, 
branches ascending. Petioles of the ground-leaves up to about 3 dm. long. Laminae of the ground- 
leaves linear, about 5 dm. long and a fourth or a fifth as broad, acute at each end ; of the lower 
stem-leaves larger, broader, truncate or asymmetrical at the base, margin more or less wavy especially 
towards the base, acute at the apex ; of the upper stem-leaves lanceolate, acute at the apex ; 
of the inflorescence-leaves, narrowly lanceolate, acute at each end. Flowers in late July and early 
August. Stamens as long as the perianth. Anthers linear, yellow. Fruiting segments triangular, 
acute or acuminate, entire or faintly denticulate towards the base, reticulated, each with a small, smooth, 
narrow tubercle. Seeds narrowed at each end, pale brown. 
