rubber, and what steps are practicable for minimising the injury caused 
by them. In every form of cultivation the attacks of some animal os- 
vegetable pest must be looked for. As in places where men or 
animals are crowded together diseases must be expected, so in plants, 
when we take them from their normal isolated position in the forest 
and put a vast number together without any separation from each 
other, an essential of cultivation, we must expect disease of some sort 
to make its way in. In the early days of cultivation, the planter was 
content to take no notice of the pests of his plants till they forced them- 
selves on his notice by nearly ruining the estate. But we have got 
beyond that stage of early ideas and now realise that it is advisable 
to attack a disease on its first appearance and keep it in check before 
it gets unmanageable. The chief diseases of plants are due to attack 
of fungi, as those of animals are due to Bacteria. In treating of fun- 
gus pests generally we can most easily sort them into classes according 
to the parts of the plant they attack, as the treatment of the disease 
depends largely on this. Thus we may group them as ( I ) Root or 
under ground Fungi, as Fomes. (2) Stem and bud Fungi as Diplodia 
or Dieback. (3) Leaf-fungi as Helminthosporiun. The two last 
being of course above-ground fungi. 
Now with the last class, Leaf-fungi, we need not trouble much, as 
Para rubber being a leaf shedder is guarded to a large extent by the 
falling of the leaves at intervals, from serious injury by the fungi of 
this group. Any leaf attacked by a fungus falls soon and the progress 
of disease is checked. It can never be as serious as the coffee leaf 
disease which attacked the long-lived thick leaves of the evergreen 
coffee. In Para rubber it is the root and stem diseases that are most 
serious and to which it is important that attention must be paid. The 
chief is Fomes semitostus. I suppose every one here knows the 
fungus by sight, and knows too approximately its life history, as far 
as that is known. I will give an account of its appearance in the 
Botanic Gardens, as an illustration of the way it attacks. The ground 
on which rubber trees had planted in about 1886, had grown to some 
extent in secondary jungle, other trees had got mixed in, and these 
had been cut out, their roots more or less removed. One day a care- 
less cooly piled up some rubbish near one of the trees and fired it so 
that two trees got badly burnt. I thought they would recover but they 
did not, and fungus attacks destroyed them ; one of these fungi was 
Fomes and this gradually spread through the adjacent trees, killing 
them one by one on each side of the first injured ones. 
Now I call your attention to the fact that there had been old 
scrub trees on the ground on which probably Fomes had been growing 
and that the burning of the rubber trees started the outbreak. The 
fungus attacked not dead, but dying trees. Is not this what practi- 
cally happens in a new clearing ? We fell the forest and burn it. This 
leaves just under ground, stumps of trees of different sizes in an inju- 
red and slowly dying state. The Fomes common in all woods, is in 
ope of these trees and begins to develop on the dying stumps. The 
