RUMEX.] POLYGONS^. 313 



"H* Fruiting sepals without tubercles on the midrib. 



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

 waved, panicle leafy at the base only, inner fruiting sepals cordate waved 

 membranous reticulate. R. domesticics, Hartman ; R. lonyifolius, DC. 

 Fields, meadows, and ditches, from Yorkshire and Westmoreland northwards ; 



ascending to 1,600ft. in the Highlands ; absent from Ireland ; fl. July- Aug. 

 Perennial, glabrous. Stem 1-3 ft., very stout. Leaves as in R. crispus, but 

 broader, 3-4 in. across. Panicles with erect branches ; whorls confluent ; 

 pedicels usually the length of the sepals, jointed below the middle. Fruit- 

 ing sepals 4-^ in. diam., obtuse, green, strongly reticulate ; midrib slightly 

 thickened. Fruit broad, small, pale brown. DISTRIB. Scandinavia (Arctic), 

 France, Germany, N. Asia, W. Asia to the Himalaya, N. America. 

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

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

 late. Monk's Rhubarb. 



Roadsides, near cottages, &c. N. of England and Scotland, rare and natural- 

 ized only ; fl. July-Aug. Perennial, puberulous with cellular hairs. Root- 

 stock 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, pedicels jointed below 

 the middle, usually twice as long as the fruiting sepals, which are J J in. 

 Fi->i/'t grey. DISTRIB. N. and Alpine districts of S. Europe, excluding 

 Russia. Root formerly used medicinally, and leaves as a potherb. 



SECTION 2. 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 quite entire scarious 

 tubercled at the base. Sorrel. 



Meadows and pastures, ascending to 4,000 ft. ; fl. May-Aug. Perennial, 

 glabrous, acid, rather succulent. Rootstock tufted, slender. Stem 1-2 ft. , 

 simple, slender. Leaves, radical 3-6 in., very long-petioled,* basal sinus 

 rounded or angled, glaucous beneath ; stipules brown. Panicle with erect 

 branches, leafless ; male whorls densely 4-8-flowered ; pedicels jointed 

 below the middle. Sepals of male fl. herbaceous, margins white or pink, 

 scarious ; of female i in. in fruit, pink or crimson. Fruit brown, shining. 

 DISTRIB. N. temp, and Arctic zones. Leaves used as a salad and potherb ; 

 abounds in binoxalate of potash. 



11. R. Acetosel'la, L.; dioecious, lower leaves hastate, uppermost 

 sessile, outer fruiting sepals appressed, inner hardly enlarged oblong- 

 ovate obtuse entire herbaceous, midrib thickened at the base. Sheep's 

 Sorrel. 



Dry pastures, &c., ascending to 2,500 ft. in Yorkshire; fl. May-Aug. 

 Perennial, acid, glabrous, often bright red in autumn. Rootstock creeping, 

 much branched. Stems &-20 in., often many and tufted, decumbent at the 

 base, slender. Leaves $-2 in., long-petioled, variable in breadth, often 3- 

 lobed ; stipules silvery, torn. Panicle leafless, branches erect ; male flowers 

 largest, pedicels as long as the fruiting sepals, jointed at the top, very 

 variable in length. Fruiting sepals A in., closely investing the yellow- 

 brown fruit. DISTRIB. N. temp, and Arctic zones ; introd. into the S. 



