482 
-destroyed by ants in such a situation as compared with a light 
soil is probably far more than compensated for by the quicker 
and more luxuriant growth of the trees that escape. 
X. — Spacing. 
The distance between the trees is also a decided factor in 
their liability to attack, the wider the spacing the smaller being 
the proportionate number of trees lost. 1 his is no doubt due to 
the desiccation of the trunks and surface soil by the sun's rays 
This slight advantage seems to be far more than counterbalanced 
by the much smaller return per acre and the slower growth or 
the trees when widely planted. 
. XI. — Influence of Season. 
White ants are much more active during periods of heavy 
rain, or rather immediately after such rain. 
XII. — Method of Attack. 
The methods of attack of 7'. gestroi are eminently characteris- 
tic, and when once their earthworks are seen and recognised, 
they can never be mistaken for those of any other species. F re 
tree seems first of all to be prospected, by two or three tunnels 
run straight up the trunk ; if the indications are favourable the 
whole circumference is then rapidly invested by a thick la}er o 
mud, under cover of which the ants speedily eat down to the 
cambium. The vast majority of attacks by individual termites 
are repelled by the cambium, but sooner or later a non-resistant 
spot is reached and the whole body of termites gains access to the 
interior of the tree, which is rapidly eaten out and falls. In a 
very considerable percentage of cases, there are no external signs 
of damage, and the insects enter the tree either by a lateral root 
from a point beneath the surface of the soil, or by way of the 
taproot itself. In such cases the tree may appear perfectly sound 
until it falls or is blown over. Damage is caused not so much 
by the actual death of the tree, for in many cases the living tissues 
are perfectly sound, but from the weakening of the trunk and 
taproot added to the natural brittleness of the wood, rendering 
them unable to resist the slightest wind pressure. On certain 
estates it has been noted, that where tapping has been somewhat 
roughly performed, and the cambium extensively cut into, white 
ants have gained access through the scars thus produced. It is 
therefore highly important that the cuts should be made down to 
but not into the cambium layer, as is the case on the Sungei 
Ren gam Estates, where in no single instance have ants secured 
a foothold in the manner indicated above. 
XIII. — General Bionomics of Themes Gestroi. 
I have not been successful, nor, so far as I am aware, has 
any other naturalist, in finding the king and queen of Termes 
gestroi. Amongst numerous communities investigated one was 
