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CULTURE OF THE GENUS CLETHRA. 
The C. ferruginea, arborea, arborea minor , and arborea variegata, are well 
adapted for the green-house or conservatory. They grow and flower well in a 
mixture of sandy loam and peat. 
All the hardy kinds succeed best in peat, and may be planted on the American 
border, amongst the other plants. 
The C. tinifolia is a stove plant, and should be potted in sandy loam. Both this 
and the green-house species are propagated by half ripened cuttings, planted in sand 
or sandy peat, and covered with a hand or bell glass ; or they may be raised from 
seeds. All the hardy species require to be increased by layers. 
CULTURE OF THE GENUS GRIFFINIA. 
The species of this genus resemble those of amaryllis, but they possess stalks to 
their leaves, and bear blue flowers. 
The G.Jiyacinthina and parviflora do well if potted in any rich mould, provided 
it be not very heavy ; if it is, mix about one-third of white sand, and beat them well 
together, but do not sift them. 
The G. intermedia requires a considerable portion of sand and peat mixing with 
the loam. 
Set them in an airy part of the stove, and be careful not to give them anv water 
when in a dormant state, but let them be well supplied when they begin to grow or 
show bloom. 
They occasionally produce seeds, but are generally propagated by offsets. 
CULTURE OF THE GENUS ONCIDIUM. 
The species of this genus are curious, and beautiful stove plants. They should 
be potted in very turfy peat, not broken fine, but left in pieces as large as walnuts, 
and mixed with broken potsherds. 
If thus potted water may be administered freely without injury, but if the soil be 
close the roots become injured, if not watered very carefully, and sometimes eveif 
with great care they will not thrive under those circumstances, 
