BALSAMINE^. 149 



Many exotic species, with yellow or reddish flowers, have at yarious 

 times been cultivated, eitlier in our flower-gardens, or, for their tuberous 

 rootstocks, as esculents. 



1. Sorrel Oxalis. Oxalis Acetosella, Linn. 

 (Eug. Bot. t. 762. Wood-sorrel.) 



Eootstock shortly creeping, slender, but often knotted with thickened 

 scales. Leaves radical, with long stalks, and 3 obovate, dehcately green 

 leaflets, with a slightly acid flavour. Peduncles radical, long and slender, 

 bearing a single, rather large white flower, and 2 small bracts, about half- 

 way up. Sepals small, ovate, obtuse, thin. Petals obovate, about 6 lines 

 long. Capsule ovoid, with 2 shining black seeds in each cell. 



In woods, throughout Europe, Russian and central Asia, and northern 

 America. Abundant in Britain. FL early spring. This is the original of 

 the Irish Shamrock, although that emblem is now represented by the white 

 Clover. 



2. Procumbent Oxalis. Oxalis corniculata, Linn. 

 (Eng. Bot. t. 1726.) 



A more or less downy annual, or, in warmer climates, a perennial, with 

 slender, spreading branches, seldom above 6 mches long. Leaves of 3 

 deeply obcordate leaflets, with small stipules at the base of the leafstalks. 

 Peduncles slender, asiUary, bearing an umbel of from 2 to 4, or rarely 5, 

 pale yellow flowers, much smaller than in the Sorrel O. 



Believed to be of American origin, but now a common weed in aU the hotter, 

 and most of the temperate regions of the globe. In Britain, only in a few 

 loeahties in southern England, except where accidentally introduced into 

 gardens. Fl. the whole season. A closely allied American species, the 

 O. stricta, with a more erect stem and no perceptible stipules, has also oc- 

 casionally appeared among garden weeds. 



The Rue of our gardens (Ruta graveolen£), and the Fraxinella of flower- 

 gardens {Dietamnus Fraxinella), both from southern Europe, belong to the 

 very large Rue family, chiefly numerous within the tropics, and in the 

 southern hemisphere, but unrepresented in Britain. The Diosmas, Correas, 

 and many other South African and AustraUan plants in our plant-houses, 

 are members of the same family. 



XIX. THE BALSAM FAMILY. BALSAMINE^. 



A. single genus, whose precise affinities are as yet very imper- 

 fectly understood, and which has therefore been established as 

 an independent family. 



I. BALSAM. IMPATIElSrS. 



Herbs, mostly glabrous or almost succulent, with alternate, undivided 

 leaves, no stipules, and very in-egular flowers. Sepals and petals all 

 coloured, and consisting usually of 6 pieces, viz. : 2 outer, opposite (sepals), 

 flat and obUque ; the next (upper sepal, although by the twisting of the 

 pedicel it hangs loweat), large, hood- shaped, ending below in a conical spur ; 



o2 



