364 PORTULACEiE. [part ii. 



ORDER LXXXIX.—PORTULACE^.— THE PURSLANE 

 TRIBE. 



The ornamental plants belonging to this 

 order, are all included in the genera Calandri- 

 nia, Portulaca, Talinum, and Claytonia ; and 

 those belonging to the first two of these genera 

 have very showy flowers. In all the species the 

 flowers have a distinct calyx, generally of only 

 two sepals, which remains on till the seeds are 

 ripe ; and a corolla of five regular petals, which 

 close in the absence of the sun. Each flower 

 has numerous stamens, and a single style with a 

 broad-lobed stigma which, is succeeded by a dry, 

 one-celled capsule, with a central placenta, to 

 which are attached numerous seeds. The cap- 

 sule opens naturally when ripe by splitting into 

 three or four valves. But the most distinctive 

 mark by which plants belonging to this order 

 can be distinguished from others with simi- 

 larly shaped flowers, is their remarkably thick 

 fleshy leaves, an example of which may be seen 

 in the leaves of Calandrmia discolor ; and these 

 succulent leaves render all the ornamental 

 plants belonging to the order peculiarly liable to 

 be destroyed by frost or damp. Some botanists 

 make a second order out of the plants usually 

 included in Portulaceae, to which they give the 

 name of Fouquieracese. 



