574 
factory. The treatment generally followed is the heaping up and 
burning of brush over the seed-bed which scorches the mould, but 
also burns the vegetable matter in the soil. 
Dr. Delacroix recommended for the Wilt-Disease which had 
broken out in cotton plantations in Egypt soil disinfection by in- 
jections of Formol of commerce (formalin) which is a solution of 
Formic aldehyde of 40 per cent. with an addition of a small quantity 
of methylated spirit which insures its keeping in that solution. 
Formic aldehyde has a higher antiseptic property than sublime 
corrosive (bichloride of mercury) which, for a long time, was con- 
sidered the most powerful antiseptic known. Moreover, it 1s 
superior to corrosive sublimate, cuprous mixtures, phenols and car- 
bolic acid, the great advantage being entirely volatile. It leaves 
in the soil no substance deleterious to vegetation like the substances 
named. It is not inflammable like carbon bisulphide which many 
shipping companies will not carry. 
Inject into the soil with the needle force pump (Pal Injector, 
page 536) like carbon bisulphide using at least 50 grammes 
(1Z0zs.) of the solution of formal per square yard, each stroke 
of the piston injecting 13 grammes of the liquid. 
INSECT PESTS. 
INJURIOUS AND BENEFICIAL. 
Of the insects attacking fruit trees and crops in Western Aus- 
tralia, the following are described in this chapter. 
For easier reference, they are given in the alphabetical order of 
their popular names. 
ANTS. 
Of these there are two main groups; the Red and the White 
Ants. The first belong to the formica family ; the second are not 
ants but are popularly ‘“ termites.”’ 
The first category of ants burrow in the ground forming “ ant- 
nests’ on lawns and paths. Ants are troublesome when the trees 
are in blossom when they climb up and bite off the stamens and 
also encourage scale insects and aphides, being very fond of the 
honey-dew they elaborate. A tablespoonful of bisulphide of car- 
bon injected into the ground, or mixed with kerosene and poured 
into holes six inches deep and a foot apart, and immediately filled 
up. Operate in the evening when all the ants are in. When the 
ants cannot be found, place a sponge soaked with sweetened water 
in their track and dip it every new 61d ef ein intc leit water. 
Another successful ant destroyer is a mixture of flour, sugar, and 
arsenic, made up to the consistency of putty with water. Pieces 
