228 
PECULIARITIES OF PLANTS 
or insect ; therefore may always be introduced with confidence ; hut, as before said, 
they ought not to be intermixed with succulents like the Gerania , Calceolaria, and 
other free-rooters, which demand constant attention to repotting with rich decompos- 
able matters ; for whatever persons who are ignorant of physiological structure 
and chemical principles may think or say, there is shrewd reason to conjecture that 
the gases from the soil and those ejected from the leaves of such rank growers, 
exert a mischievous influence upon the foliage of all other plants of a habit 
dissimilar. 
As to succulents proper — Aloes, Cacti, Stapelia, Mesembryanthemums, &c., &c. 
- — they transpire but little, and therefore produce but a trifling influence upon the 
atmosphere of a house ; yet, though not commonly remarked, many of the species 
are greedily devoured by snails and slugs. Even the Epiphyllum speciosissimum, 
with its tremendous armature of spines, becomes an easy prey to the snail, by which 
it is pierced and bored full of holes, with impunity to the molluscous vermin. 
In the stove, or warmer flower-house, there are several tribes, of great beauty, 
which are apt to suffer from the scale turtle or coccus, and mealy insects. Such are 
the Orange and Lemon, plants which, if once touched, become covered with scale : 
the poisonous, but most lovely Nerium, in all its varieties, and the Cape Jasmine 
(' Gardenia ), are also in the like predicament. It is not easy to dislodge the enemy 
completely, yet a brush with a lather of soft soap and plenty of soft water will keep it 
in check, but the case admits of no neglect. The mealy scale is still more insidious 
and injurious, and washing with innoxious fluid is the only safe remedy. Every one 
should avoid chemical solutions, particularly those of the metallic salts. Some are 
absolutely poisonous ; and thus it has been proved that stems of the Orange, and 
other firm-wooded shrubs absorb fluids ; for a very little arsenic has killed a plant 
in the course of a few hours. 
All the plants of the Gesnera family are worthy of every care ; they are rarely 
injured or infected ; though aphis has occasionally been observed. By watching the 
development of roots from leaves, parts of leaves, or cuttings, particularly those of 
Gloxinia, a great deal of structural knowledge may be obtained : all the Achimenes, 
also, are charming and safe plants. The good old Hibiscus rosa sinensis, in all its 
varieties, single and double, lias never been rivalled ; but the approach of aphis upon 
the young shoots must be jealously watched, otherwise, hundreds of tender leaves 
will fall, and then not one healthy shoot can be procured. 
totally 
AEschynanthus. — The plants of this genus are of easy culture, and beautiful in 
foliage and flower : they approach, but do not belong to the epiphytes or parasites ; 
the Hoy as also are extremely fragrant and of singular structure : we know of no dis- 
ease to which they are liable. Enough has been said to warn and encourage — but 
the subject could be extended to a hundred pages. 
