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; 
THE AUSTRALIAN NATURALIST. 171 
MURRUMBIDGEE IRRIGATION AREAS. 
By Keir C. MckKrown. 
BAG MOTH (THARA SP). 
During the Spring and early Summer months the curious 
egg-clusters of this moth are frequently brought into the office 
by settlers for identification; there having been “numerous 
instances in which the eggs have been deposited on the leaves 
of grape vines—usually upon the upper surface of the leaves 
These ege-masses are on the average about the area of « 
shilling piece and contain several hundred eggs, the whole mass 
being thickly felted over with brown seales and down from the 
body of the parent moth. The eggs usually hatch in a couple 
of days, the young hairy larvae feeding upon the epidermis and 
down on the surface of the leaf for about 4 or 5 days, and then 
die; the food apparently not being suitable for the young 
larvae—this has occurred in every case under observation. The 
reason for the parent moth depositing her eggs upon this 
unsuitable food plant, is probably due to the fact that owing to 
intense cultivation, almost all native timber has been cleared 
from the Area over an area of several square miles; the moths 
are therefore hard pressed for suitable food plants on which 
to deposit their eggs. 
The egg-clusters closely resemble those deposited on <Acacin 
pendula which give rise to the Bag Moth common on these 
trees. 
MOUND ANT (IRIDOMYRMEX DETECTUS). DAMAGING 
CITRUS TREES. ‘ 
During October 1919 several reports were received from 
sattlers on the Area that Ants were doing considerable damage 
to Citrus trees. On investigation I found that the Ant causing the 
injury reterred to, was the common Mound Ant (Iridomyrmex 
detectus) which was present in large numbers on individual 
trees, cutting the blossoms to pieces and stripping the bark off 
the wood of the soft young growth. 
In some cases the wood was completely girdled or in other 
instances the damage was even more serious; the young growth 
being completely severed from the main stem or hanging only 
by a shred of bark with several ants clinging to the stem and 
industriously gnawing at the cut stump. The damage in most 
cases extended from the tips of the young growth for several 
inches down the stem and even on to comparatively hard and 
seasoned wood. 
