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throw up earthy runs on Para trees. The Lacessitus merely eats 
portions of the dead bark, but the Gestroi bores in and destroys the 
tree. 
Detection. 
The Gestroi can be distinguished from the Lacessitus by the 
following peculiarities : — The nippers of the large soldier ants are 
red, and a white milky fluid will exude from the front and top of the 
head if pressed : the soldier ant of Gestroi will always attack when 
molested. 
Remedy to be Applied. 
When the runs of “Gestroi ” ascend the tree, either partially or 
entirely, encasing it with mud, the following method should be 
adopted : — 
At the base of the tree where the collar touches the ground. 
remove with a broad straight pointed knife a portion of the mud 
encasement. This will reveal several small tunnels. Insert the knife 
into one of these, and by gently levering the earth away from the tree 
the aperture is enlarged. When sufficiently widened to admit the 
nozzle of the fume pump, gently insert it : press clay round nozzle to 
prevent any escape of fumes. Pump fumes into the tunnel. Take 
great care not to block the tunnel when widening the aperture, and 
do not push the nozzle in too far. Where fumes escape stop the hole 
with earth. When a field is being treated instruct the coolies not to 
remove the mud encasements on the outside of the tree, as they reveal 
the tunnels. The fumes used are those obtained from 9 parts of Ars- 
enic Oxide to I powdered Sulphur on red hot charcoal. 
Pumping should be continued for 6 minutes. The nozzle ol pump 
should be occasionally withdrawn to ascertain whether pump is in 
working order. 
The tree has also to be pumped into, this is done as follows : — 
With an auger slightly larger than the pump nozzle, bore a hole in 
the trunk of the tree to its centre at the collar ; pump into this hole 
for 6 minutes, or until the pump ceases to work from back pressure 
of fumes ; plug up all holes in tree or surrounding ground emitting 
smoke; and, finally, when the tree and runs are full of smoke, plug 
the bored hole in the tree with a well fitting sound wooden plug, 
tarred. This plug must be driven into the tree level with the wood 
(not bark). The ant runs are frequently 100 yards and more in length. 
Open the runs in about three days and see if the operation has been 
successful; if not, repeat. Thoroughly inspect all tree stumps and 
logs for ants, and if any are found, carry out the same operations 
as above. 
Temporary Preventive Measures. 
The eradication as above set out, i.e., pumping, lakes a 
considerable time, and as there may be many trees on the Estate 
