Part ATI] Beeson : Life History of Toon Borer. 
15 
Second generation. 
By the time the second brood larvse are abundant, the flowers of 
the toon are falling and the young fruit capsules are developing.* The 
larvae feed on the fruits, selecting the youngest and softest while in 
the first instar and feeding mainly on the epidermis. Older larvae 
attack more advanced fruits and feed mainly within them, eating 
the seeds and the soft white tissue of the dissepiments and the axis, 
and avoiding the harder epidermis of the valves. Larvae of the first 
instar are rarely able to penetrate the outer epidermis of the fruit capsule, 
if it is at all suberised, and in the absence of softer green fruits are unable 
to feed. During the feeding period the fruits are bound together in 
groups of 3 to 5 with silk-web, in which are entangled brown desic¬ 
cated fragments of fruits and pellets of excrement [Plate IV, fig. 10]. 
A larva lives inside one fruit until the edible portions are consumed, 
on which it emerges, and bores a hole into the fruit immediately along¬ 
side, fastening the new fruit to the one previously occupied with 
silk threads. While feeding within a fruit the entrance hole is 
plugged by a compact mass of excreta and ejected fragments of pith 
[fig. 11]. 
Dispersal and pre-pupal movements. 
Larvae of the first and second generations, when full grown, lower 
themselves from the crown of the tree, in the early morning, by means 
of silk threads. Many, checked in their descent by the lower branches, 
abandon the thread and crawl down the trunk. Those that reach the 
ground direct, invariably again crawl up the trunk of the tree in search 
of crevices or recesses in the flakes of bark on the bole and larger branches 
suitable for pupation, and there is a constant movement of larvae in all 
directions on the trunk and adjoining undergrowth. During the course 
of their wandering silk is continuously spun in the paths of individual 
larvae, and in the case of badly infested trees, especially those with 
smooth bark, the quantity of silk spun is sufficient to form a connected 
sheet of silk-web round the whole bole of the tree, from the crown 
branches to the ground. 
If the food supply on any branch of a tree is exhausted before the 
brood is full-grown, the larvae drop down and migrate to other trees 
or other parts of the same tree. The majority of larvae observed acting 
* There is naturally considerable variation locally and among individual trees in the 
dates of flowering and the ripening of fruits. The majority of trees fruit in May, 
but it is not uncommon to find young fruits and ripe fruits which have shed their seeds, 
at one and the same time. This does not influence the habits of the broods as mucn 
as would be expected; an early moth of the second generation is more likely to lay 
eggs on the buds or leaveB of early shoots than on late but still attractive fruits. 
[ 160 ] 
