GG 
INSECTS AND DISEASES 
REENFLIES are the most formidable of the insect 
foes we have to deal with on house-plants. They 
come on the young growing shoots of most plants, 
Ki and if left alone increase with marvellous rapidity. 
8 \ In greenhouses they can easily be dealt with, as one 
or two good strong smokings with tobacco-stalks 
will destroy all fully developed insects. In a house where 
fumigation is out of the question greenflies must be got rid of 
by means of washing, dipping in weak tobacco water, or by 
dusting the young shoots with tobacco powder. Mealy-bug is 
a curious, disagreeable insect, and cannot be got rid of except 
by washing it away with a sponge or picking it out of 
the axis of leaves and other corners where it cannot be other- 
wise reached. It does not, however, increase in any alarming 
degree, and with a little ordinary care is not likely to cause 
any trouble in a house. ‘The same can be said of the scales, 
a similar kind of insect that is frequently found on American 
trees such as the Sassafras and the Chionanthus. 
The Thrips and the Red Spider are liable to attack many 
plants if kept too dry. The only means of freeing house-plants 
of these is by a good, thorough washing with a strong solution 
of fir-tree oil or some other insecticide ; they can generally be 
