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Connexion with Scale or other Insects .—On the orange leaves, 
for instance, affected with scale insects, yon may sometimes find 
little clear gummy globules, sweet to the taste. These are pro¬ 
duced by the insects as figured and described by the late Mr. 
Maskell, in his work on New Zealand Scale Insects. “ In many 
cases,” he writes, “ they exude, in the form of minute globules, a 
whitish thick gummy secretion, answering probably to the 
* honey-dew ’ of the Aphididte. This secretion drops from them 
on to the plant, and from it grows a black fungus, which soon 
gives an unsightly appearance to the plant. This fungus or 
‘ smut’ is an almost invariable indication that a plant is attacked 
by insects, and may, indeed, give a useful warning to tree- 
growers.” And as J. G. 0. Topper, of Adelaide, has shown, 
there is a complex relation between the different forms of life 
used by the plant for protective purposes, and if one of the checks 
is withdrawn or diminished the balance is disturbed and disorder 
ensues. 
1. The Scale or other insects are used indirectly to attract the 
ants by their sweet secretion. 
2. The Ants, like a standing army, protect the foliage against 
the attacks of leaf-eating animals. 
3. 1 ho abundance of honey-eating Birds is necessary to keep 
the scale or other insects within reasonable bounds, as they not 
only use the honey, but eat the insects as well. 
4. Tho reduction of these birds by man tends to favour the 
increase of the scale insects and their produce. 
5. Tho scale and other insects now get the upper hand, and 
the ants protecting tho insects also favour their increase. 
(5. d he consequence is superabundance of honey-dew, and 
this is taken advantage of by the germs of tho fungus to spread 
and multiply. 
llius the destruction of the honey-eating birds has brought 
about an increase of the honey-dew, and consequently of the 
u Sooty Mould.” 
1 he dependence of the Sooty Mould on the presence of the 
scale or other insects secreting “ honey-dew ” indicates at once 
the lino of treatment—that if the scale be destroved the food 
supply of the Sooty Mould is cut off. The Scale-Ant-Bird-1 "ungus 
problem opens up large issues as to man’s interference with nature 
which cannot be followed out here ; but it shows on the face of it 
that, even for the eradication of some fungus pests, insectivorous 
birds should be protected for the benefit of the grower. 
Entomogenous Fungi as aids against the “ Sooty Mould.”— 
It is interesting and profnable to observe the appearance of other 
checks to the spread of the scale insects. While examining 
leaves infested with “ Sooty Mould ” from New South Wales, I 
discovered a fungus parasitic on the Bed Scale of Orange and 
