161 
THE BONNGGA WEEVIL, 
Cyrtotrachelus sp. 
This weevil lives principally in the trunks of the betel palm, Areca 
catechu Linn., where it does great damage, but inasmuch as it has also 
been found in considerable numbers in coconut trees, it is here described 
as far as its habits and appearance are concerned. In addition to the 
larvee of the rhinoceros beetle and the cocoons and grubs of the palm 
weevil, one frequently encounters in decaying betel palms or coconut 
trees of 6 to 8 years, other smaller cocoons not more than 35 millimeters 
long and 15 millimeters in diameter. (PI. VII, fig. 4.) These are com- 
posed of a more finely comminuted fiber than those of the palm weevil, 
and upon opening appear to contain a dwarfed example of the pupa of 
the Asiatic weevil. However, this pupa differs in many respects from 
that of Rhynchophorus ferrugineus Fabr., and the frequent finding of 
beautifully marked weevils of very small size convinces one that these 
cocoons and pupe belong to the former. 
Ligg.—No eggs have been encountered, and attempts at confining the 
adults for the deposition of eggs under conditions as nearly natural as 
possible have failed. 
Larva.—The full-grown larva is nearly of the same size as the preceding one. 
However, in form it is more like that of the Asiatic palm weevil and is probably 
somewhat closely related to it. The color is a light-ocher yellow. The head 
is very much darker, and the mouth parts are dark-brown. 
The length is 20 millimeters and the diameter 6 millimeters near the rear third 
of the body, the form being strikingly like that of the Asiatic weevil in this 
particular. The head projects forward and is smooth and shiny, with but few 
hairs scattered over it. 
The spiracles on the first thoracic segment are larger than any of those on the 
other ones of the body, with the exception of the last abdominal segment, on 
which they are well developed and placed on the posterior aspect. The apex of 
the last segment is somewhat flattened and its hinder margin is prolonged into 
4 rather obscure tubercles, from each of which arise 2 bristle-like hairs pointing 
posteriorly and slightly downward. Certain areas on the skin of the entire body, 
except the head, are rough or very minutely shagreened, single isolated hairs 
arising from some of them. 
The mouth is minute, but the upper and lower lips and the mandibles are well 
developed, the latter being black. The palpi are prominent. As with the larve 
of Rhynchophorus ferrugineus Fabr., there are no evidences of external eyes or 
ocelli. (PI. XI, fig. 1.) 
Pupa.—The pupa is illustrated by fig. 3 on Plate XI. Its length is 13 millimeters 
and its greatest diameter 6 millimeters. It is of a whitish-ocher color, certain of 
the tubercles being a darker ocherous. On the front of the head, just above the 
point where the eyes would appear in thesadult, there are 2 prominent corrugated 
tubercles, each with a single bristle; anterior to these are 2 smaller ones with 
bristles; and on the snout or rostrum above the antenne are 2 more. On the 
front margin of the thorax are 2 other tubercles, smaller than the largest on the 
head; on the anterior half of the thorax toward the sides is another pair; and 
near the posterior margin are 2 others slightly larger; all of these are provided 
