WOOD-SORREL TRIBE 167 



small acquisition to a garden destined to supply a large family with vegetables 

 during the winter season. 



The beauty of the flowers of many of the Wood-sorrels has led to the 

 culture by gardenei"s of nearly a hundred species. One of the prettiest and 

 most early-blooming is the Oxalis cernua, the Drooping Wood-sorrel, which 

 has bright yellow flowers, with a most delicious jessamine-like odovu' ; though 

 there is one disadvantage attending it as an ornamental plant, which is, that 

 the flowers all remain closed, not only in wet and cloudy Aveather, but in any 

 spot on which the sun is not shining in full power. The blossoms of our 

 woodland species are much affected by light, never expanding on a dull day. 

 They are produced in April ; but Curtis remarked a circumstance respecting 

 them Avhich all of us who have watched this plant can verify. He says, 

 " If attentively observed, it will be found to continue producing seed-vessels 

 and seeds during the greatest part of the summer, without any appearance 

 of expanded blossoms, which are only observable at one period of the year." 

 Since Curtis' day it has been noted that several other plants — we have 

 already mentioned the case of the violets — bear these never-opening or 

 cleistogamic flowers, which unfailingly produce abundant seed, without insect 

 aid or expenditure of flower-material. 



Whether the leaf of the Wood-sorrel, or of one of the clovers, is the 

 ancient "shamrog' of Ireland, is a question which has led to much learned 

 disputation, and which will be noticed more fully when we reach the trefoils. 



2. Yellow Procumbent Wood-sorrel {0. cmiiiculdta). — Stem 

 branched ; branches prostrate ; stalks usually 2-flowered ; leaves ternate ; 

 stipules united to the base of the leaf-stalks. Plant annual. This species, 

 which has small yellow flowers, is not nearly so elegant a plant as the 

 Common Wood-sorrel. It is in flower from June to September, in shady 

 woods in the south-west of England. Though so rare in Britain, it is a 

 common flower in many countries of Europe, especially in the south, as in 

 Spain and Italy. It is also found in Japan and Mexico ; and in the latter 

 country the flowers are much larger than in the English specimens. A 

 yellow-flowered Sorrel, termed Oxalis microphylla, is very common in 

 Australia. Mr. Backhouse says that it displays its lively blossoms in almost 

 every grassy spot in the colony of Van Diemen's Land, and that its acid 

 leaves resemble in form those of the clover. It is eaten in its fresh state by 

 the natives to allay thirst ; and when made into tarts, is scarcely inferior to 

 the fruit of the barberry. This traveller also found a white-flowered Wood- 

 sorrel, 0. ladea, generally dispersed over the colony, but not growing any- 

 where in sufficient quantity to be of any service. 



Oxalis strida is a yellow-flowered species, and is said to be naturalized in 

 gardens near Penzance, and in fields near Northam, in North Devon. It 

 differs from Oxalis cornieulata in its more upright and less branched stem, in 

 the greater number of its leaves, Avhich, in some specimens, surround the 

 stem in a whorl ; in its flowers growing in an umbel, and in the absence of 

 stipules at the base of the leaf-stalks. 



