ENTOMOLOGY. 
209 
the plants, it is advisable to keep them for a few days in a high moist 
temperature, which will either kill or banish every enemy of the 
plants. 
The latter part of this prescription is, perhaps, the most effectual 
for driving the insects; and, indeed, it is now found, that, to recover 
sickly pine plants, and free them from insects, it is only necessary to 
put them upon a brisk stable-dung heat. The ammonious gas arising 
from the dung appears to be at once fatal to the insects, and nutritious 
to the plants. This circumstance has induced many pine-growers to 
raise, not only their successions, but also their fruiting plants, entirely 
on dung heat. 
Many stove-plants are liable to be preyed on by the coccidts ; and if 
at any time they are not in free growth, or are particularly delicate in 
their shoots and foliage, they may be freed from the insects by being 
removed to a dung hotbed for a few days. The only thing to be 
guarded against in making such a trial is, not to expose delicate plants 
to the steamy heat of dung, which assuredly would be as fatal to the 
plants as to the insects. Orange-trees, myrtles, camellias, and all such 
firm leathery-leaved plants, may bear such a fumigation for a short time 
safely; but no herbaceous-leaved plant could sustain the effects of the 
effluvia but for a very short time. 
When hothouse or greenhouse plants are seized by the scale, they are 
usually removed by a stick thinly pointed at one end, and a bit of 
sponge tied on at the other, with which the scales are loosened, and 
washed off with a weak solution of tobacco or quick lime in soft water. 
This, however, is a tedious process, and only effectual to stop the 
increase, rather than extirpate the insects. Frequent steaming, and 
sprinkling with water offensive to them, are the best preventives. 
Succulent plants, which cannot safely be drenched with water, should 
be fumigated by some noxious vapour, as sulphur, or the like, in a 
frame by themselves. A fumigating frame, of rather large dimensions, 
should be an appendage to every establishment where exotic plants, 
whether useful or ornamental, are kept; it would be found very useful 
for many purposes of the garden, for which neither a pit nor common 
frames without risers are adapted. 
A species of coccus is sometimes met with on peach, nectarine, and 
grape vines under glass. The females become very large in the spring; 
the hinder part of the scale is raised up to allow a white cotton-like 
bag of their young to grow, and afterwards escape. At this time they 
are easily removed by the back of a knife, or by a hard brush. 
The coccidce which infest forest-trees, -— as the poles of ash and 
the red or broad-leaved willow,—-are of two kinds : the scales of the one 
VOL. v. 
NO. LX. 
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