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•also suggest it for the Grain Plant-louse Aphis granario , where found 
on winter wheat in the spring before gathering about the heads- For 
the latter species Dr. Fitch recommends dusting the grain with dry 
power of chloride of lime. 
For the Carrot Plant-louse (Aphis dauci) Curtis recommends dusting 
powdered tobacco over the crowns early in the morning while the 
due is upon them, or watering them with a decoction of tobacco. 
The most effective remedy where it can be applied, is tobacco smoke 
or the fumes of burning tobacco, sulphur, etc. But to render these 
successful the plant must be covered in some way, so as to confine 
the smoke or fumes and cause them to penetrate to all parts. A frame 
in the shape of a box or bell, covered with cheap cloth of any kind, 
will answer very well for the flower or vegetable garden, and might 
be used also for small bushes. 
Various means of using this remedy will suggest themselves in con¬ 
nection with the means at hand and the plants to which it is to be 
applied; the object to be attained being, to confine the smoke of the 
fumes immediately around the lice long enough to suffocate them. 
Sometimes a minute or two will suffice, where the application is strong 
and direct; but usually ten or fifteen minutes, or even longer will be 
necessary, where the lice are numerous and in compact colonies. 
It is possible that an apparatus may be invented for the direct ap¬ 
plication of tobacco smoke or sulphur fumes, something on the plan of 
sand bellows, with which painters dust sand over woodwork, or sim¬ 
ilar to the Babcock extinguisher. 
If it possible to bring into use, at a reasonable expense, something 
of this kind sufficiently large to reach, through hose or pipes, the 
limbs of trees, it would be exceedingly useful not only against ap¬ 
hides but numerous other insects. 
REMARKS. 
Although, as heretofore stated, most cultivated as well as uncultivated 
plants are more or less subject to the attacks of one or more species 
of plant-lice, yet in England, and I believe so far as observed in this 
country, clover appears to be singularly exempt. 
The potato, which is subject to the attacks of so many other in¬ 
sects appears to have no plant-louse peculiar to it' or that can pro¬ 
perly be called a potato plant-louse. It is occasionally attacked by the 
Bean Aphis, and some other species, but it is very rarely ’the case, 
that it is injured by these insects. Curtis states, that in 1847, when 
the Aphides were abundant in certain parts of England, destroying the 
bean crop, potatoes in the same garden were not injured. Harris 
speaks of plant-lice sometimes infesting potato fiields, but I presume 
he alludes to the occasional visitations, such as I have mentioned. 
In this country the apple, plum, cherry, currant, willow, grape, cab¬ 
bage and a few other vegetables appear to suffer most from the attacks 
of these insects; occasionally wheat and corn are injured somewhat 
