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POPULAR GARDEN BOTANY. 



Echinoc actus, Melocactus, Opuntia, PeresJcia, and Cereus, re- 

 quire the heat of the dry stove to make them flower well ; 

 and though they are sometimes introduced into the green- 

 house among other plants, they are considered not to suc- 

 ceed in the cool and moist air. Many of this tribe can 

 live in the greenhouse or room, and even out-of-doors in 

 summer, but they always require to be placed in a hothouse 

 to make them push forth buds, and they may then stand in 

 the greenhouse during their greatest beauty, and be returned 

 to the stove when the season of flowering again approaches. 

 Cactus (Cereus) speciosissimus, the common South Ameri- 

 can species, is a long, erect, quadrangular plant, with deep 

 furrows, and rich scarlet flowers ; it will blossom in a dry 

 greenhouse, as will several others, but they are better in a 

 house devoted to them, as they do not bear the moisture of 

 atmosphere requisite for other plants, and even if they do 

 they still want the heat of a stove to make them flower well. 

 Some cultivators succeed in keeping them altogether in the 

 greenhouse, and forcing them to flower, but they require 

 more attention than the amateur can give : one great secret 

 seems to be, that of keeping them quite dry in the winter. 

 The following species of Cereus are recommended for sus- 

 pending in pots in the greenhouse : amabilis, Dalstonii, ele- 



