BOTANICAL STRUCTURES. 289 



elude the evil effects of damp by regular airing in mild, dr} 

 weather, and to attend to slight watering where it may be 

 needed. 



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 early spring, so as to have a store for plant- 

 ing out in June. 



Of late years, particular genera of plants have com: 

 greatly into vogue, and it would be an omission not to no- 

 tice some of them. Among 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, not a mere infu 

 sion of tobacco.) If the plant be small, it may be dipped 

 into 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 certainlj- 

 superior in elegance of form, is the family of Cape heathy, 

 or Ericas. 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 mede 

 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 Ericas require a peaty and sandy 

 soil, and great attention in watering and giving plenty of 



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