GREENHOUSE PLANTS. 



257 



used to clothe arid banks in the gardens near Naples and elsewhere 

 thus giving the effect of a grassplot. This class of plants, which 

 has been much neglected, is useful in hot, burning situations, and will 

 probably become fashionable with the higher class of gardeners. 



We have a few Cacti. Notwithstanding their interesting forms 

 and magnificent flowers, these plants are often discarded, because 

 they are stubborn, and will flower when they like, and so are not well 

 adapted for flower shows. This year several species were planted out 



FIG. 523. Echinocactus tubiflorus. 



FIG. 524. Cereus grandiflorus. 



in a hot, dry border, and the one figured (fig. 523) shows well the 



splendour of their flowers. The Creeping Cereus is a common 



species, easily flowered. The Midnight Cereus 



(Cereus grandiflorus, fig. 524) comes into flower 



towards evening with great rapidity, and then 



may be cut, when it will last three or four 



days. Cacti are desirable plants to grow in 



greenhouses attached to dwellings, because they 



give off no odour. Probably the Cactus-house 



at Kew is the most perfect glass-house in the 



world, exhibiting as it does the entire group 



of succulent plants at a glance. 



The Cereus speciosissimus (fig. 5 2 5) i- s a 

 plant which created a great sensation when it FIG. 5 2 5 .-cereus s 

 was first introduced. Its grand, brilliant flower is most effective. It 

 requires full exposure to sun, and a long season of rest, when it 



s 



