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MANUAL OF BOTANY 



them. This is supposed to be the case more particularly with 

 Vaccaria vulgaris. Saponarin officinalis has been used in 

 syphilis ; it contains a peculiar principle called saponin. This 

 principle has also been found in species of Lychnis, Silene, 

 Cucuhalus ; and more especially in Gypsophila Struthium, to 

 which latter plant it communicates well-marked saponaceous 

 properties : hence it is commonly termed Egyptian Soap-root. 

 The other species in which saponin is found also possess, to 



Fig. 1057. 



Fig. 10.59. 



Fig. 1058. 



Fig. 1060. 



Fig. 1061. 



Fig. 1057. Diagram of the flower of a species of Dianl/tifa. — Fiij. 1058. Ver- 

 tical section of tiie flower of tlie Riime. — Fitf. 1059. Sporopbylls of a 



species of Slellaria. Fig. 1060. Capsule of a species of Dian/7ms, dehiscing 



partially in a valvular manner so as to form four teeth at the apex. 



Fig. 1061. Vertical se:;tion of the seed of Chicliweed {Stellarja media}.] 



some extent, similar properties. Saponin is reputed to be 

 poisonous in its nature. 



Some of the plants have showy flowers, as the species of 

 Dianthus, Silene, and Lychnis ; but they are generally insig- 

 nificant weeds. Dianthus harbatus is the Sweet- William of our 

 gardens ; D. plumarius is the parent of all the cultivated 

 varieties of the common Pink ; and D. Caryophyllus, the Clove 

 Pink, is the origin of the Carnation and its cultivated varieties. 



