530 



A TEXT-BOOK OF BOTANY. 



beautiful flowers, which expand only in the sunshine. The com- 

 mon ice-plant of the gardens, so called because of the numerous 

 glistening globules of water which cover the leaves, is M. crystal- 



FIG. 294. Soapwort, Bouncing Bet (Saponaria officinalis}, a perennial herb growing 

 to a height of 3 to 6 dm. and producing opposite, entire leaves, and cymose clusters of rose- 

 colored flowers, commonly double. This plant has been more or less cultivated; it has, 

 however, escaped from the garden, and, in spite of its beauty, has become a troublesome 

 weed in some places. The plant contains saponin and therefore forms a lather with water. 

 It has been used as a detergent. After Brown. 



Union. This plant as well as other species of Mesembryanthemum 

 are used in medicine. The ashes yielded by the plants of this 

 family also contain soda. The seeds of some species of Mesem- 



