U-2 OXALlDE^ 



Lake, on the banks of Windermere, and is said to be plentiful by some little 

 rills near Rydal Hall. It occurs, more rarely, on the sides of the Avon, 

 near Salisbury, near Fountains Abbey, and in several other places both in 

 England and Wales. The stem is about a foot high, round and succulent, 

 and, like that of the garden Balsam, which belongs to the same genus, is 

 very brittle. The flowers are large, and yellow, spotted Avith orange ; and 

 the foliage is so acrid as to be refused by all animals except the goat. Boer- 

 haave considered the plant poisonous, and though it has been used medicinally, 

 yet its use was generally considered by the medical profession as attended 

 with danger. Its Latin name, noli-me-tdngcre, is significant of the manner in 

 which its seed-vessel curls up its valves spirally at the slightest touch, jerk- 

 ing its contents into the face of him who bends over it. The leaves are 

 expanded during the daytime, but hang drooping at night. 



Professor Lindley accounts in the following manner for the action of the 

 seSd-vessels. The tissue of the valves consists of cellules gradually diminish- 

 ing in size from the outside to the inside, the fluids of the outer cells being 

 the densest. The latter by degrees empty the inner cells, and distend them- 

 selves so that the external tissue is disposed to expand, and the internal 

 to contract, Avhenever anything occurs to disturb the force which keeps them 

 straight. This at last happens l)y the disarticulation of the valves, the 

 ilower-stalk, and the axis, and then each valve rapidly rolls inwards with 

 a spontaneous movement. M. Dutrochet proved that it was possible to 

 produce this phenomenon by putting some fresh valves of this Balsam into 

 sugar and water, which gradually emptied the external tissue, and after 

 rendering the valves straight, finally curved them backwards. 



The American Jewel-weed, /. fulva, has become naturalized on the banks 

 of the Thames at Hampton Court, on the Wey near Guildford, and along 

 the Grand Junction Canal. It has also appeared along the Clyde, and other 

 places, its spread being very rapid, owing to the distance to which the 

 ,spring-gun-like capsule discharges the large seeds. The spur of the calyx 

 of this flower is notched and bent under so closely as to press against the 

 sepals. The Garden Balsam is the Impaticns halsainina ; it is a native of 

 the East Indies, and its beautiful varieties of carnation or purplish blossoms, 

 studding their amber stems, are among our most common garden annuals. 

 The seeds often surprise the unwary by suddenly jerking out on some slight 

 touch. 



Order XXII. OXALIDE^.- WOOD-SORREL TRIBE. 



Sepals 5, not falling oft' ; petals 5, equal, often united at the base, twisted 

 while in bud ; stamens 10, the 5 outer ones shorter than the others ; filaments 

 generally combined at the base ; ovary 3 — 5-celled ; styles 3—5 ; capsule 

 3 — 5-celled, with as many, or twice as many valves ; seeds few, inclosed in 

 an elastic case, which curls back on the ripening of the fruit, and throws the 

 seeds to a distance. The Order consists of herbaceous plants, or under 

 shrubs, which are remarkable for the acidity of their foliage, and for their 

 sensitiveness. Several are astringent, and their acid flavour has rendered 

 many among them agreeable additions to soups, salads, and confectionery, 

 as well as useful for medicinal and various economical purposes. 



