ii8 THE TROPICAL AGRICULT.URIST [August i, 1893. 
them ill a convenient form for the uae of plant' rs 
engaged in coconut palm growing, who, according to 
the Commi'sioners, appear to be generally "unac- 
quainted with 'he various stages in the existence of 
the Weevil ; " and to serve as a guide towards 
obtaining a more thorough knowledge of the insect's 
habits and of the class of measures most efficieut in 
keeping it in check. The present paper has been 
written and is published as the result of that decision. 
II.— SounCES OF iNiOKMATION. 
The Palm Weevil of UenU-al and South America 
(lilii/iichophorus pahnarum, Linn.) is one of the tropical 
insects, with which zoologists have been longest 
familiar . . • ^■ 
There is another and distinct species, the Asiatic 
Palm Weevil, or " red-beetle " of the planters, (Itliyu- 
chophoius ferruyinem, Fabr.), a native of Indi* and 
the Malay region, which also attacks the coconut 
palm, and closely resembles its American congener 
in habits. There has always been a tendency on the 
part of writers to confuse these two species, a tend- 
ency which no doubt has caused the geographical 
vagaries referred to. Though closely allied they 
differ in appearance, if not in habits ; and it is 
desirable to remember that writers who speak of 
the Palm Weeul in Asia as lilii/nchophorus oi Calan- 
dra palmarum are referring to U. fen ugirwna, and not 
to the American weevil. Attention to this point is 
necessary, particularly in the study of periodicals 
devoted to tropical agriculture, in which the mis- 
take is constantly made. 
III. Habits and Llfb History ok the Palm 
Weevil.- The Palm Weevil is one of the largest in- 
sects contained in that very important and extensive 
group of beetles, the Weevils, of which the most 
characteristic feature is the prolongation of the head 
forwards so as to form a snout or rostrum, some- 
limes of great length, into the sides of which the 
horns of antenna: are inserted. The snout, which is 
always distinguishable in the true weevils, bears at 
its extreme tip the mouth, very small but never- 
theless efficient. 
The mouth is used for feeding, and by the females 
in drilling holes, which operation is rendered possi- 
ble by its position at the en l of the snout, or in 
nibbling patches from the rind of p'ants in which 
the eggs are then laid. There has been a good 
deal of misunderstanding about the snout of the 
Indian Palm Weevil, and it has been several times 
said that that insect possesses no. alimentary appara- 
tus whatever. This is not the case. The beetle, 
like other weevils, which are, at a rule, long-lived 
insects in the adult state, can and does feed, and 
the observer, mindful of the elephant, has probably 
looked for the mouth under the head, at the base 
of the snout, which he has taken to be merely a 
horn with peuetrating power limited by the force 
with which the beetle can drive it in, The insect 
can pierce far harder tissues by gnawing than it 
could ever do by mere pushing. 
When the grub has become mature by continuous 
feeding, broken, however, by intervals when it changes 
its skin and emerges from its old garment clad in a 
new and larger one, it transforms by a further change 
of skin into a pupa. This takes place near the stirface 
of the plant, so that the perfect insect, whose burrow- 
ing powers are inmost of the true weevils limited, can 
break without dif&culty through the structures which 
shield it from the air. The yupa, sometimes enclosed 
in a cocoon or covering constructed by the grub, 
resembles the perfect insect, but is soft and pale with 
the wings and limbs neatly folded do wn on its under 
side. Xhe limbs are separately enclosed in a thin 
skin which is not continuous over the surface, as in 
the pupa of a moth. Aa a pupa the insect lies dor- 
mant for a shorter or longer time, taking no food and 
being absolutely harmless. At last the perfect beetle, 
which has slowly matured in the pupal covering, 
throws it off and issues forth. It is at first soft and 
pale, and remains in shelter till its outer integuments 
have hardened, when it sets forth on its work of feeding 
and reproduction. If an American Palm Weevil is 
carefully examined from above, it is seen to be a large 
o\al befltlfl with its upper eurfape slightly flat^^ned 
and of a deep velvety-blacV, with little or noloatre. 
Specimens which are glossy appear to have lost their 
vtlvety pile by being rubbed, and h>».ve probably 
emerged some time; ihey frequently have a bhiny 
streak along the middle of the ba.ck, while the Bidc« 
are dull. 
The statement that all the larger and more balky 
specimens are females is wrong ; both sexes are very 
variable in size. 
The structure of the weevil is not adapted for bur- 
rowing into hard vegf-table tissues, and it does not do 
80, though it may creep into crevices, or dig its way 
into loose, rot'en material and soft structures like the 
split cabbage of a palm, in which they arc sometimes 
found. In boring beetles the body is narrow and 
cylindrical, so as to fit the burrow, and the snout, if 
present, is short and strong, while the shanks, aii a 
rule, are strengthened with teeth or spines set along 
their outer edge, sometimes for excavating, aiiiially to 
resist the friction of burrowing, and to throw out of 
the burrow the debris that is bitten away. The Palm 
Weevil, with its unarmed shanks and its \ery am all 
mouth, would have great difficulty in making a hole 
big enough to accommodate it in the trunk of a tree, 
and when specimens are found inside a tree, they 
have got there either through a wound, by entering 
the hole of another insect, or the soft parts of 
the split bud, or have been bred in the tree 
and not yet quitted it. In the latter case the 
immature beetlea will be found near the surface 
with a thin layer of rind between them 
and the outer air, through which they can easily 
break. One observer speaks of finding the ' parent 
beetle and three large grubs wrapped in the fibre 
about three inches from the baric." The beetle 
certainly was not the parent of the grubs, and it mast 
be distinctly borne in mind that, except perhaps 
when the tree has external wounds, the beetle does 
not bore but lays its eggs from the outside. 
The perfect weevils are mainly nocturnal in habit, 
and fly at dusk or by night with a loud booming 
noise (the Indian weevil is said, however, to fly 
frequently bj' day as well). They hide from 
daylight in rubbish at the foot of the trees, and 
occasionally, it is stated, burrow in sand ; they 
are also to be found concealed in the folds of the 
leaf-sheaths and the matted fibre of the head of the 
tree, or in the holes made by other insects. Ihey 
feed freely on decaying sap or fruit, such as mangoes 
or bread fruit, and on the rotten tissues of the palm- 
and cabbage pith, to which they are attracted by the 
smell of the fermenting juices, a circumstance that 
affords the readiest and best means of capturing them.* 
In the adult state they are not known to injure 
the palms for the purpose of feeding, and as they are 
the parents of further broods of destructive grubs, the 
chief point for study in their habits is the method 
of egji-lnyiug, which is rtguloted hy the i'.,gtinct of 
the insect to place its eggs iu a situation where the 
inactive grab can, npon hstching, get the food it 
rt quiree. 
Whether a tree 'u selected for egg-laying in pre- 
ference to others is obviously determined by its condi- 
tion at that time. As a rule, the act of egg-Ia^ing 
passes unuoticed, and the health of the tree only 
becomes a subject for ii qnry sometime later, when the 
work of the grubs is apparent ; and the inquiry is 
therefore complicated by the necessity for distinguish- 
ing between an nuhealthy condition occaring as a 
result of the iofestatioa, snd one which may have 
originally brought it about. 
The temale is stated to lay ber eggs singly, in ac- 
cordance with the habit of other weevils, by perforating 
the rind of the tree and depositiog au egg in the bole 
mad>'. The appearance of the egg^^ and the number 
laid by each female have not yet been recorded. 
It ia desirable to know the exact spot selected for 
oviposition in order that it may be artificially protected. 
At present the evidence does not place it beyond doubt. 
It ia generally admitted that eggs are not laid in 
* They also frequent freshly planted sagar-cane 
seta, in which the female deposits her eggs ; this 
habit is as yet unrecorded from Honduras. 
