658 OXALIS. [CLASS X, ORDER IV. 



GENUS XX. OXA'LIS. LINN. Wood-sorrel. 

 Nat. Orel. OXALI'DE^E. DE CAND. 



GEN. CHAR. Calyx of five pieces. Petals five, often united at the 

 base. Stamens ten, the filaments often slightly united at the base, 

 the five outer ones shorter. Styles five. Capsule five angled, 

 five or ten valved, five celled. Seeds with a fleshy arillus. 

 Name from ofuf, sharp or acid; some of the species containing in 

 their juices oxalic acid. 



1. O. Acetos'ella, Linn. (Fig. 749.) Common Wood-sorrel. Leaves 

 all radical, ternate ; leaflets inversely heart-shaped, pubescent ; scape 

 single flowered, longer than the leaves, with a pair of bracteas above ; 

 the middle petals notched ; rhizoma scaly. 



English Botany, t. 762. English Flora, vol. ii. p. 323. Hooker, 

 British Flora, vol. i. p. 214. Lindley, Synopsis, p. 59. 



Hoot with long creeping cord-like underground stems, with here and 

 there a tuft of fibres and fleshy scaly rhizomas. Stem none. Leaves 

 all radical, on slender erect footstalks, mostly scattered over with hairs, 

 pale, often pinkish, and bearing at the top three sessile or nearly sessile 

 leaflets, of a fine pale cheerful green colour, somewhat paler beneath 

 than above, becoming pink, inversely heart-shaped, finely veined, and 

 more or less clothed with pubescence. Scape round, slender, mostly 

 longer than the leaves, scattered over with hairs, and bearing above the 

 middle a pair of ovate membranous braclca. Flowers solitary, ter- 

 minal. Calyx of five ovate oblong thin pieces, equal, hairy. Petals 

 much longer than the calyx, oblong, more or less emarginate, with a 

 short claw, having on each side of it a gland, by which they are united 

 together, white or pinkish, with finely penciled veins, of deep purple 

 colour, Stamens ten, on awl-shaped filaments^ in two rows, mostly 

 united at the base, the outer row shorter than the inner. Anthers 

 ovate, yellow, of two cells. Styles long, slender, with feathery stigmas. 

 Capsule narrow, of five angles, opening with five valves, sometimes ten, 

 five celled. Seeds numerous, invested with a fleshy arillus. 



Habitat. Woods and shady places ; frequent. 



Perennial ; flowering in May, and in lofty alpine situations as late 

 as August. 



The Wood-sorrel is an extremely pretty ornamental plant in the 

 shady woods and groves in many parts of the country, clothing them 

 with the beautiful garment of its cheerful looking leaves of delicate 

 green, and decorated with its handsome drooping flowers of pure white, 

 (inely ramified with purple veins. The leaves on the under side arc 

 frequently of a dark purple colour, and during the day the leaflets are 

 horizontally extended, but on the approach of evening they are droop- 

 ing downwards over its stalk. This sensitiveness in the movement of 



