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This grub works its way forward through its burrows by a combination 
of twisting and undulating motions. In this it is aided by the tubercular 
enlargements on the thoracic segments. ‘The hind end appears to offer no 
help in this respect. It can enter from any opening through which the 
head will pass. The bristles on the head serve as guides for the insect in 
passing through holes. When placed upon a level surface, the grub moves 
slightly sidewise, almost always upon its side, and can thus make fairly 
rapid progress. 
The breathing apparatus in BR. ferrugineus Fabr. consists of only two pairs of 
spiracles which are well developed, the others being almost rudimentary. Each 
of the first pair is situated laterally on the first thoracic segment, and twice its 
own length below the shiny, transverse, shield-like areas, and the second pair just 
above the spoon-shaped excavation of the thirteenth segment of the body. The 
latter two are one and one-half times as large as the first two, and their openings 
are nearly vertical, diverging slightly below. The other segments of the body 
show the spiracles only when examined under a strong lens; these are nonfune- 
tional, or at most only very slightly so. 
The galleries of this grub run obliquely through the large swollen part 
of the tree near the roots. (PI. VIII, fig. 3.) The specimen here 
depicted was full of grubs of all sizes and contained one or two pupz as 
well. Adult beetles were also found in considerable numbers. ‘The grubs 
have been encountered in the crown of the tree in numbers varying from 
15 to 20, where they work side by side with those of the rhinoceros beetle, 
and it is very difficult to distinguish the galleries of the one from those of 
the other. Plate III, fig. 1, shows a longitudinal section of the crown of 
a tree which has been eaten out in the form of an inverted cone by the 
larve of the rhinoceros beetle and the palm weevil in company. Plate 
VIII, fig. 3, shows the work of the weevil in the lower part of the tree very 
near the roots, some of which are seen at the lower right-hand corner. It 
will be noted that the galleries run obliquely, which shows that the grubs 
work inward and upward from the outside of the tree. In this case the 
eggs were evidently laid in wounds in the root region, on the left, and 
the grubs worked their way toward the center where the full-sized galleries 
are seen. 
Pupa.—When the larva of the palm weevil has attained its full size, it 
ceases feeding and evacuates the alimentary canal, thus causing a shrinkage of 
one-third in its size immediately before making its cocoon. This is elliptical in 
outline, from 8 to 12 centimeters long and 5 to 6 millimeters in diameter, and 
composed of the long tough fibers of the coconut trunk wound as shown by 
Plate VII, fig. 3. It is closely woven and thick, so that the pupa is well pro- 
tected against dampness. The grub sheds its skin and takes the form shown by 
Plate VII, fig. 2. The pupa measures 35 to 40 millimeters in length and about 
15 millimeters across its widest portion, The snout is doubled down on the 
breast; the antenne, wings, and other organs of the beetle are plainly visible. 
The color is a uniform pale-ocher, the tips of the knees being darker. Rugose 
areas are situated on each side of the head, back of the eyes, on the upper part of 
the snout, on the outer fore and hind regions of the pronotum, on the ridges of 
the elytra, and on the dorsum of the abdomen, These areas are rather thickly 
