i820 A TEXTBOOK OF THEORETICAL BOTANY 



differ in having ten stamens united at their base, in having five styles and in the 

 mode of dehiscence of the fruit. The family is essentially a tropical one with 

 seven genera and some 850 species. There is only one British representative, 

 Oxalis acetosella, the Wood Sorrel (Fig. 1720). In many species the flowers 



Fig. 1720. — Oxalis acetosella. Wood Sorrel. 

 Flower. 



are trimorphic (Fig. 1721), there being three kinds of plants, those with 

 long style and medium- or short-length stamens; secondly those with 

 medium or short styles and with long and medium stamens; and thirdly 



Fig. 1721. — Oxalis speciosa. Trimorphic flowers. A, Short 

 styles, long stamens. B, Medium styles, long stamens. C, 

 Long styles, short stamens. (After Darulii.) 



those with long or medium styles and short or medium stamens. In O. 

 bupleiirifolia and some other species, the ordinary leaves are replaced by 

 phyllodes. The tubers of O. deppi and others are used for food. Many 

 species develop subterranean, cleistogamic flowers if the normal flowers fail 

 to set seeds. Oxalic acid may be prepared from Oxalis acetosella, where it 

 occurs in the leaves in the form of the Potassium salt. 



