CLASS VI. ORDER II.] OXYRIA. 517 



ORDER II. 



DIGYN'IA. 2 Pistils. 



GENUS XXII. OXY^RIA.— Hill. Mountain Sorrel. 



Nat. Ord. Polygo'ne^. Jdss. 



Gen. Char. Perianth of four pieces, the two outer ones smallest. 

 Stamens six, two at the base of each of the inner segments, and 

 one at the outer ones. Styles two. Stigmas tufted. Fruit a 

 nut, with a winged membranous margin. — Name from o^v<; 

 sharp or sour ; from the acidity of the plant. 



1. O. renifor*mis, Hook. (Fig. 591.) Mountain Sorrel. 



Hook. Scot. vol. i. p. 111. — British Flora, vol. i. p. 170. — English 

 Flora, vol. ii. p. 188. — Lindley, Synopsis, p. 211. — O. digyna, Campder. 

 monogr. t. 3. f. 3. — Rumex digynus^ Linn, — British Flora, t. 910. — 

 Rheum digynum, Wahlenb. Lapp. 101. t. 9. f. 2. 



Root of long tapering fleshy branches, mostly divided and tufted at 

 the top. Stem solitary, erect, from four to six inches high, roundish, 

 striated, or furrowed, smooth, almost leafless, terminating in a branched 

 panicle. Leaves numerous, radical, on long slender striated footstallis, 

 from the base of a thin brown membranous stipule, all kidney-shaped, 

 with a more or less evident sinus at the apex, or abrupt, the margins 

 more or less waved, of a bright green, paler, and sometimes purplish 

 beneath, thickish, with branched radiating veins from the top of the 

 footstalk. Flowers numerous, arranged in whorled racemes, more or 

 less crowded on the erect slender simple or divided branches, each 

 flower on a slender simple rarely branched peduncle, arising from the 

 base of a thin membranous bractea, which is somewhat sheathing at 

 the base. Perianth of four pieces, the two outer ones narrower than 

 the other two, which are roundish, ovate, three ribbed, not becoming 

 larger after flowering, of pale green, slightly tinged with pink. Sta- 

 mens shorter than the perianth, two arising from the base of the larger 

 inner segment of the perianth, and one from each of the others. Fila- 

 ments slender, anthers of two oblong lobes, of a purplish colour. 

 Styles short, reflexed, with purple tufted much divided stigmas. 

 Fruit a nut, enclosed in a thin membranous utricle, ovate, compressed, 

 with a broad dilated winged margin, notched at the apex between the 

 persistent styles, pale green, tinged with purple, and the base enclosed 

 iu the persistent dried petals. 



Habitat. — Damp mountainous situation, between the clefts of rocks, 

 ^c. in the North of England, Wales, and Scotland ; frequent. On 



VOL. I. 3 Y 



