MONTHLY NOTES ON GRUBS AND OTHER CANE PESTS. 25 
Mr. R. D. Rex, a prominent grower at South Mossman, told me that 
his place never suffered from grubs, though the beetles were always in 
evidence about the feeding-trees in his yard. He said that the beetles 
simply swarmed about the figtrees at night, and that the coconut leaves 
were badly eaten by them. We saw many beetles on these palms. 
Mr. Rex always plants early, which is evidently best for clay soils; 
but his practice of thoroughly preparing the ground by doing the horse 
work while the beetles are on the wing probably saves him from grub 
attack. 
Mr. Rex made the interesting observation that fruit bats congregate 
in beetle-feeding trees, even where there is no fruit for them to feed 
upon. He found the ground strewn with broken parts of beetles next 
morning, indicating that the bats had been feeding upon the insects. We 
would appreciate any further evidence along this line. 
The Mowbray district appears to be free from grey-backs, for I 
could not find a bettle on the feeding-trees. Following up the report that 
grubs were in evidence at this season, I found that the frenchi grubs 
were doing slight damage in some of the newly-planted land. The pest 
was only noticeable on the high spots in the field, where the humus is 
naturally washed out of the soil. The cane in the low places was growing 
strong, with no sign of injury. I also noticed that bandicoots had dug 
holes in search of grubs in the infested stools, but had not molested the 
healthy cane. 
FurTHER EVIDENCE OF THE EFFECT OF LIGHT ON THE GREY-BACKS. 
A benzine lantern of high ecandle-power was taken under the feeding- 
trees by the Mossman Bridge, and the beetles began swarming around it 
at once. An ordinary lamp, though giving much less light, appeared 
equally attractive, probably because, having no cover, the rays went 
straight up into the tree. I was told that placing the lamp upon a white 
sheet made it more effective, for the white surface acted as a reflector ; 
and by this means the beetles could be more easily gathered up. 
It is my experience that these beetles are much more easily attracted 
to lights soon after emergence than they are later on, when almost ready 
for ovipositing. 
FEEDING-TREES OF THE BEETLES. 
By a thorough examination of the scrub, which at Mossman borders 
most of the cane land, I was able to note the principal feeding-plants of 
the grey-back beetles. This examination is facilitated by the fact that 
this species remains on the feeding-plant during the day. 
Several new feeding-plants were observed, some of which we are not 
yet able to name, being unfamiliar with the scrub flora. However, it 
will be interesting to know that the Candle Nut (Aleurites molucanna), 
a tree with broad, coarse leaves, is much sought after by the beetles, and 
the foliage is often eaten right to the midribs. Since these plants are 
so generally distributed it will be well for canegrowers to recognise 
