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When this happens the greater part of the larval life is often 
passed in this mutual condition. 
By choosing for its first haunt the very young shoots which have 
not yet opened the necessity of drawing the leaf edges together for 
concealment is avoided, seclusion being naturally afforded by the 
unopened leaf. The irritation caused by the larva to the young leaf 
prevents its subsequent opening in the natural manner. 
The length of the young caterpillar is from 2-2’5 mm., (|th inch) 
its head varies greatly in colour, the abdomen is reddish pink. 
If we examine a newly attacked tree and open the young shoots 
containing the larvae, we shall find that the epidermis of the leaf is 
being eaten away in, sometimes a tortuous manner, in others in 
irregular small patches which appear of a fresh green colour and 
may be distinctly seen against the dull green of the upperside of the 
young leaf. 
When the epidermis has been partially devoured, fresh leaves are 
searched for, and it is fairly typical of this species to draw the some- 
what older leaves surrounding the young shoot around the latter, 
devouring these as necessity arises. It is unlikely that less than 
20 eggs laid by the female of this insect, so that if we take this 
as the minimum number it’ will be obvious that a week after the 
larvae have appeared and have dispersed into the young leaves, no 
new buds are visible, the surrounding leaves have been drawn 
together encircling the former, and forming a leaf house. These 
bunches of leaves may be seen on nearly all the Gutta Percha trees 
here. 
When the larva is about five days old and the leaf house is formed, 
it commences mining in earnest. Starting from either the base or 
apex of a leaf it eats the epidermis regularly on either side of the 
midrib, leaving untouched pnly the extreme edges of the leaf. One 
half is however soon abandoned, the larva confining its attacks to one 
side of the leaf the epidermis of which is rapidly eaten. Its size by 
the 8th day has greatly increased being, 18 mm. (£ inch) and in the 
majority of cases it now vacates its original house taking possession 
of fresh leaves on some other part of the tree. This is again aban- 
doned in a few days and yet another house is formed. Thus a 
single larva by repeatedly changing its house, besides killing the 
new shoots and the adjacent younger leaves, also destroys several 
mature leaves, and the combined effects of the larvae hatched from 
the eggs laid by a single female have a very disastrous effect upon a 
tree. 
About fourteen days after batching the larva is adult; it makes its 
escape by pushing its way through the dead part of the leaf and 
dropping to the ground it pupates just below the surface. Three 
weeks later the adult insect emerges. 
While occupied the leaf is always moist inside, a condition neces- 
sary to the well being of the larva, and in addition it has in all 
probability the effect of decomposing to a certain extent the tissues 
of the leaf. 
