. Bulletin of entomological research. Entomology. INSECTS IN SUGAE-CANE PLANTATIONS IN FIJI. 23 are grown, and as the borer prefers soft sweet stalks of cane to tnnnel in, it almost invariably happens that on similar types of soil Badila suffers much more severely than Malabar. The white elongate oval egg of this pest is about one-sixteenth of an inch in length, and is laid in the rind of the stalk behind a half-loosened leaf-sheath, and a week after oviposition the grub hatches out and bores into the cane, becoming full-grown in eight to eleven weeks. In boring the cane the grub destroys a ve
. Bulletin of entomological research. Entomology. INSECTS IN SUGAE-CANE PLANTATIONS IN FIJI. 23 are grown, and as the borer prefers soft sweet stalks of cane to tnnnel in, it almost invariably happens that on similar types of soil Badila suffers much more severely than Malabar. The white elongate oval egg of this pest is about one-sixteenth of an inch in length, and is laid in the rind of the stalk behind a half-loosened leaf-sheath, and a week after oviposition the grub hatches out and bores into the cane, becoming full-grown in eight to eleven weeks. In boring the cane the grub destroys a very large amount of tissue, partly by eating and swallowing it, and partly by chewing it to extract the sap. The tunnels made are not infrequently two feet long, but generally they do not extend to more than six inches ; in tunnelling the cane the grub frequently eats too close to the rind, and in doing so it makes small rupture holes about the size of a pin's head. The borer grubs can be readily located by the presence of these holes, which stand out somewhat conspicuously as a result of the rind in their immediate vicinity being of a rather lighter shade than elsewhere. The full-grown grub measures somewhat more than half an inch in length, and is legless, wrinkled and yellowish grey in body colour, the head being light reddish brown. The fifth and sixth adbominal segments are greatly swollen Fi°\ 1. Rhabdocnemis obscura, Boisd., X 3. The full-grown grub prepares for pupation by eating a hole in the rind of the cane somewhat less than a quarter of an inch in length, and at a short distance above this hole it pupates in a cocoon of fibres separated from the tissue in which it has been tunnelling. The cocoon is extremely strong, and as it is very difficult for anything to penetrate it, the pupa is generally immune from the attacks of the small brown ant (Pheidole megacephala, F.); were the cocoon less strongly made a large proportion of the pupae would undoubtedly p
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