BOTANICAL STRUCTURES. Q89 
clude the. evil effects of damp by regular airing in mild, dry 
weather, and to attend to slight watering where it may be 
needed. a, 
It is worthy of remark, that many species of green-house 
plants flourish much more luxuriantly, and make a finer 
appearance when in flower, if planted in the open border 
during the summer months. Cultivators should therefore 
diligently propagate such plants by cuttings in pots placed 
in hotbeds in éarly spring, so as to have a store for plant- 
ing out in June. 
Of late years, particular genera of plants have come 
greatly into vogue, and it would be an omission not to no- 
tice some of them. Aniong the foremost may be mentioned 
Pelargonium, with its affinities. The Pelargoniums are 
of easy culture, being propagated readily by cuttings, and 
requiring only to be shifted from time to time. Young 
plants are very liable to be attacked by the aphidion or 
green fly. The most effectual cure is tobacco-water (as 
procured from manufacturers of tobacco, net a mere infu- 
sion of tobacco.) If the plant be small, it may be dipped 
inte the liquid for a minute or two, not only with impunity, 
but with great advantage, the insects being thus killed. 
Equal to these, in point of beauty of color, and certainly 
superior in elegance of form, is the family of Cape heaths, 
or Zrice. Of this genus there are said to be 600 species, 
considerably more than the half of which exist in our col- 
lections. Many heaths may be raised from seed, which oc- 
casionally ripens in this country: the most common mcde 
of propagation, however, is by cuttings, and this in some 
species is attended with difficulty. Very small cuttings 
are stuck into the purest white sand, and closely covered 
with bell-glasses. The Erice require a peaty and sandy 
soil, and great attention in watering and giving plenty of 
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