350 POL YGONA CEJE. [RUMEX. 



8. R. Hydrolap'athum, ffuds. ; leaves broadly oblong-lanceolate, 

 panicle almost leafless, inner fruiting sepals deltoid-ovate acute or obtuse 

 quite entire or faintly toothed, all with oblong tubercles. 



Ditches and river-sides from Perth and Isla southd. ; Ireland ; Channel 

 Islands ; fl. July-Aug. Perennial, glabrous. Stem 3-6 ft., erect, branched. 

 Leaves 1-2 ft., acute, base rounded cordate or acute, margins flat crenulate ; 

 petiole 6-10 in., flat above, not winged. Panicle'verj large ; whorls rather 

 crowded ; fruiting pedicels as long or twice as long as the sepals, jointed 

 near base. Fruiting sepals 5-^ in., reticulate, base truncate or cuneate. 

 Fruit pale chestnut. DISTRIB. Europe. The largest British species. Root 

 astringent. 



li. Hydrolap'athum proper ; petioles flat, base of inner fruiting sepals nar- 

 rowed. VAR. latifo'lia, Borr. (? R. max'imus, Schreb.) ; margins of petioles 

 raised, base of inner fruiting sepals truncate or cordate. Essex, Hants, 

 Sussex, Cornwall, Scilly Is. 



"|~f* Fruiting sepals without tubercles on the midrib. 



9. R. aquat'icus, L. ; lower leaves oblong-lanceolate crisped and 

 waved, panicle leafy at the bq.se only, inner fruiting sepals cordate waved 

 membranous reticulate. R. longifo'lius, DC. 



Wet meadows and ditches, from York to Shetland ; ascends to 1,600 ft. in 

 the Highlands ; fl. July-Aug. Perennial, glabrous. Stem 1-3 ft., very 

 stout. Leaves 3-4 in. diam. Panicle with erect branches ; whorls con- 

 fluent ; pedicels usually the length of the sepals, jointed below the middle. 

 Fruiting sepals 5 | in. diam., obtuse, green, strongly reticulate; midrib 

 slightly thickened. Fruit broad, small, pale brown. DISTRIB. Scandi- 

 navia (Arctic), France, Germany, N. and W. Asia, Himalaya, N. America. 



R. ALPI'NTTS, L. ; leaves broadly ovate-cordate obtuse, panicle leafy at 

 the base only, inner fruiting sepals triangular-ovate obtuse faintly reticu- 

 late. Monk's 



Roadsides, near cottages, &c., N. England and Scotland, rare, naturalized ; fl. 

 July-Aug. Perennial, puberulous with cellular hairs. Rootstock very stout. 

 Stem 2-4 ft., stout. Leaves 6-24 in., not so broad, margins waved ; petiole 

 long, stout. Panicle with very many erect branches ; whorls very many, 

 not confluent; flowers monoecious; fruiting sepals, -f in.; pedicels twice 

 as long, jointed below the middle. Fruit grey. DISTRIB. N. and Alpine 

 districts of S. Europe, excluding Russia. Root formerly used medicinally, 

 and leaves as a pot-herb. 



SECTIONS. Aceto'sa, Tournef. Leaves hastate or sagittate. Flowers 

 monoecious or dioecious. 



10. R. Aceto'sa, L. ; dioecious, -lower leaves sagittate, upper sessile, 

 outer fruiting sepals reflexed, inner enlarged orbicular entire scarious 

 tubercled at the base. Sorrel. 



Meadows and pastures, N. to Shetland, ascends to 4,000 ft. ; Ireland ; Channel 

 Islands; fl. May-Aug. Perennial, glabrous, acid, rather succulent. Root- 

 stock tufted, slender. Stem 1-2 ft., simple, slender. Leaves, radical 3-6 in., 

 very long-petioled, basal sinus rounded or angled, glaucous beneath ; stipules 



