Polygonum.] POLYGONE^E. 223 



HC * Flowers dioecious. Plants acid. (Acetosa or Sorrels.) 



9. R. Acetosa, Linn. Common Sorrel. Enlarged sepals or- 

 biculari-cordate, reticulated, scarcely tubercled ; leaves ob- 

 longo-sagittate. Br. Fl 1. p. 170. E. Fl. v. ii. p. 196. E. 

 Bot. t. 127. 



Meadows and pastures, frequent. Fl. June, July. 1. Stem 1 2 

 feet high. Lower leaves stalked, with two lateral teeth, upper ones 

 sessile. Clusters erect, leafless. Flowers reddish. 



10. R. AcetoseUa, Linn. Sheep's Sorrel. Enlarged sepals 

 ovate, not tubercled; lower leaves lanceolato-hastate, lobes 

 entire. Br. FL 1. p. 170. E. FL v. ii. . 197. E. Bot. t. 

 1674. 



Dry pastures, frequent. FL May July. % . Variable in size from 

 2 to 10 inches, and in the form of its leaves. 



2. OXYRIA. Hil. Mountain-Sorrel. 



Perianth of four sepals, the two inner ones rather largest. Nut 

 triquetrous, with a broad membranaceous margin. Embryo 

 erect, inverted. Name from ogvs, sharp or acid, from the 

 acid flavour of this, as of many other plants belonging to 

 the same natural family. Hexandria. Digynia. 



1. O. reniformis, Hook. Kidney-shaped Mountain- Sorrel. 

 Br. FL I. p. 167. E. FL v. ii./.. 188. E. Bot. t. 910. 



Moist alpine rocks. On Magillycuddy's Reeks, and Brandon moun- 

 tain, county of Kerry ; and on Ben Bulben, county of Sligo. FL 

 July, Aug. %. " Stems 8 10 inches high, with rarely more than one 

 leaf, often naked. Radical-leaves numerous, all reniform, with a more 

 or less evident obtuse sinus at the apex, on long footstalks, having mem- 

 branaceous stipules at their base. Racemes and peduncles branched, 

 with minute, ovate, membranaceous bracteas at the base of each rami- 

 fication. Pedicels thickened upwards. Flowers erect, small. Sta- 

 mens 6, shorter than the sepals. Pistil nearly orbicular, compressed, 

 notched, with two feathery spreading styles. Fruit a nut, enclosed in 

 an utricle, with a remarkably broad winged border, tipped with the 

 styles, situated in rather a deep notch, and having at the base the 

 pointed sepals, not at all enlarged." Hooker. 



3. POLYGONUM. Linn. Persicaria, Knot-grass and Buck- 

 wheat. 



Perianth single, in five deep, coloured, persistent segments, 

 inferior. Stamens 5 8. Styles 2 3. Fruit a one-seeded, 

 compressed or trigonous nut. Named from TroXvs, many, and 

 7<>>i;, a knee or joint ; from the numerous joints of the stem. 



Octandria. Trigynia. 



