54 WOOD-SORREL. 



as in some plants, by the elasticity of the seed- 

 vessel, but by the bursting of the covering 

 which invests the seed itself. The roots are 

 like coral beads strung together, and the leaves 

 are more sensitive than those of any other of 

 our wild flowers, closhig during darkness or at 

 the approach of a storm. They are said, by 

 some, to show some irritability on being struck, 

 but this statement the author has not found to 

 be true. 



The triple leaf had, in former days, some 

 superstitious veneration attached to it, and the 

 plant was consequently called AUelujah. Some 

 of the early religious painters of Italy in- 

 troduced it into their pictures ; and the author 

 of the work called " Modern Painters," refers 

 to this use. He remarks : '' Fra AngeHco's 

 use of the Oxalis acetosella is as faithful in 

 representation as touching in feeling. The 

 triple leaf of this plant and white flower, 

 stained purple, probably gave it strange typical 

 interest among the Christian painters." Some 

 persons believe that this w^as the Shamrock, 

 the plant chosen by St. Patrick to illustrate 

 the doctrine of the Trinity. 



