February i, 1890,] THE TROPICAL AGRICULTURIST. 
579 
COCONUT BEETLES AT THE STRAITS. 
Mr. C. F. De Moruay, of Malakoff Estate, Province 
Wellesley, writes as follows to the Pinang Gazette : — 
The proposed " Ordinance for the protection of 
Coconut trees from the ravages of certain Beetles" may 
seem to persons unacquainted with the cause of the great 
increase in the number of these insects quite unneces- 
sary ; but when they know how impossible it is for the 
owners of coconut plantations to prevent their property 
being destroyed by one of these beetles, they will, I think, 
acknowledge that the Government is acting wisely and 
justly in coming to their assistance. Though it may 
not be advisable for Government to protect or foster 
any particular branch of industry, it is only fair that it 
should step in to protect one threatened with destruc- 
tion, through no fault or want of care on the part of 
those engaged in it, but by the neglect of certain 
duties for which other people are properly responsible. 
These duties are the destruction, removal, or render- 
ing innocuous of rubbish, trade refuse, &c., produced 
in their business or on their premises. As regards the 
draft Ordinance published in the Government Gazette, 
I am of opinion that, it its present form, it would 
not have much effect in checking the ravages of the 
beetles, and that a more intimate knowledge of their 
habits is required before a suitable measure can be 
framed. The drastic remedy of cutting down all the 
coconut trees attacked by beetles would cause serious 
loss to the owners without any appreciable benefit. 
If not trespassing too far on your space, I propose 
making some observations on the habits of these insects, 
which, I hope, will prove useful in suggesting means 
for reducing their numbers. 
The Rhinoceros beetle (described as Oryctes Rhi- 
noceros in the schedule to the proposed Ordiuance) is, 
I think, too well-known to need description here. It 
is by far the most numerous and destructive of these 
pests. Only the perfect beetle of this species attacks 
living coconut trees, the larva? or grubs living only in 
decaying vegetable matter. I mention below some of 
the materials that seem to be the most attractive beds 
for breeding these beetles: — 
1. Paddy straw. 
2. Paddy husk. 
3. Coir refuse, rubbish from dust bins, bark, tan, 
saw dust, &o. 
4. Cattle manure and stable litter. 
5. Dead trunks of coconut trees. 
Certain other kinds of refuse are said to breed these 
insects, but of these I cannot speak from personal know- 
ledge. It is remarkable that the stems of the tapioca 
plant and the ampas (refuse from the roots), when 
rotten, never breed these beetles. Whole coconut 
husks, when heaped until quite decayed, also prove 
uuattractive. It is possible that by analysis Govern- 
ment might determine what it is that makes these 
substances unpalatable to the insects, and thus dis- 
cover means of preventing their breeding in other refuse. 
The beetle lays its eggs in some accumulation of 
moist and decaying vegetable matter, where the larva, 
a whitish grub, is duly hatched, and lives until it 
attains its full size, about 2i inches long, and as thick 
as a man's middle finger. It then becomes a chrysalis 
of a light-brown colour, the forepart of which resem- 
bles the perfect beetle, except that the head, horn, 
wings, and legs are enclosed in a kind of casing. It 
still inhabits the refuse heap until the time for it to 
takes its flight as a perfect beetle. The beetle leaves the 
place it was bred in always at night, and flying in the 
direction of the prevailing night wind, reaches a coconut 
tree, alights on it, and proceeds to bore into a leaf near 
the butt ; often boring through young unfolded leaves, 
which gives them the cut, ragged appearance so often 
seen after they unfold. The beetle sometimes passes 
the day in tho holo it has bored, and, being unable 
to fly by day-light, is found by the coconut treo 
climbers, who extract it by moans of a barbed needle. 
This plan answers well enough in keeping down the 
number of beetles on a plantation, if there are no large 
accumulations of rubbish or trade refuse, &o, s in the 
neighbourhood ; but when this is the case, or the 
plantation is situated near a village, it is impossible to 
cope with the inseots iu this manner, and the trees 
rapidly sicken and die from repeated attacks. The 
only means I have found practicable, when these beetles 
become too numerous to be kept down by extract- 
ing them from the trees, is to search for and destroy 
the grubs iu their breeding places, or to render these 
unsuitable for hatching and feeding them. 
Paddy straw is a favorite breeding place when stocked 
in the usual manner, the grubs being found only in 
the layers nearest the ground, which are always damp 
and more or less decayed. I successfully prevented the 
grubs being bred in this by having the straw stocked 
on a platform of split bamboos (nibongs or saplings 
would answer equally well) sufficiently high to keep 
the ground underneath free from litter, and to allow 
for ventilation. Not a single beetle or grub ever bred 
in straw stacked in this manner, and it is a cheap 
and effectual plan of dealing with it. Indian cattle 
are chiefly fed on paddy straw, and their introduction 
here has caused the natives to purchase or collect it for 
that purpose. It is usually stacked near the cattle- 
sheds, and provides numerous large beds for breeding 
the beetles. Paddy straw is used largely at potteries, 
and is usually stacked in the same manner. On account 
of there being now a market for the paddy straw, the 
Malays often neglected to burn it off on their fields, 
as used to be customary, and the heaps left rotting 
there may also breed beetles. Paddy husk is another 
favourite breeding place, and should be burnt as pro- 
duced, unless it is required for any purpose, when it 
should be stored in raised magazines. Near rice-pound- 
ing establishments in Province Wellesley, the coconut 
trees die in large numbers from the attacks of beetles. 
It is sometimes used at potteries. Coir refuse, rubbish 
from dust bins, tan, bark, &c, are mostly difficult, if 
not impossible, to burn, and should either be thinly 
spread over adjacent land, or, as I would suggest, 
emulsions of J eyes' purifier, carbolic acid, kerosine, 
Paris green, or some other insecticide might be 
sprinkled over the heaps with the idea of preventing 
the grubs from breeding in them. Cattle manure has 
to be heaped for some time in order to render it suit- 
able for manure, and is too valuable to destroy by 
burning 1 , in agricultural districts. The grubs are usually 
found a few inches from the surface of the heaps, so 
they are easily discovered and destroyed ; but I think it 
might also be treated in the way suggested for dealing 
with coir refuse, &c. Large numbers of beetles are bred 
in the stable litter at the homes of Europeans and natives 
in Penang, which must greatly increase their numbers. 
The beetles have no particular breeding season, but 
breed all the year round. 
Red Beetle, (?) named Rhynchophorus Ferrugineous 
in the draft Ordinance, is I think, probably a variety 
of Calandra Palmarum. I have never found any of 
these beetles of a uniform red or orange colour as 
mentioned in Dr. Simon's'report on coconut beetles. 
This beetle itself does no harm to coconut trees. It is 
the larva or grub that damages them. It has been 
generally stated that the beetle searches for wounds in 
the coconut tree made by the coconut climbers with 
their knives, and deposits its eggs in them, but I think 
it more probable that it acts in a similar manner to 
other beetles of the same family, as, for instance, the 
corn and rice weevils, and itself punctures the hole 
where it deposits its eggs. It has been said that their 
rostrum is not sufficiently strong for it to do this, but 
in my opinion it is quite strong enough to punch a 
hole in the soft parts of the crown of the tree, which 
is probably much softer than a grain of corn or rice. 
The grubs are hatched in the pithy material, usually 
called the cabbage, through which the leaves sprout. 
They bore through this and the soft part of the tree 
in all directions, without, however, making any ex- 
ternal wound. If not discovered, they eventually kill 
the tree by eating through the base of the leaf spike, 
probably through their favourite food, the cabbage, 
having become entirely consumed. When a grub living 
in a coconut tree arrives at the time it has to change 
into the pupa or chrysalis state, it bores through the 
wood of the stem to the outside, near the top of the 
tree, and, on the thickness of the wood, manufactures 
a most wonderfully constructed cocoon from the fibres 
of the wood, In this it lies torpid until the time for 
