_Female._ Length 13 lines. Black; closely and finely punctured; the clypeus convex and strongly punctured, emarginate anteriorly, the emargination with a yellow border; the eyes extending to the base of the mandibles, which have three stout teeth at their apex and a narrow yellow line at their inner margin. Thorax: the postscutellum yellow, and a minute yellow spot on the outer margin of the tegulae; the wings rufo-hyaline, darkest along the anterior margin of the superior pair; the nervures ferruginous, gradually becoming darker at the base of the wings, the costal nervure black. _Worker._ Length 9 lines. Very closely resembles the female, but in addition to the yellow markings of that sex has the anterior margin of the clypeus yellow, a narrow transverse line between the antennae, another along the lower margin of the notch of the eyes, an abbreviated stripe behind them at the base of the mandibles, a spot beneath the postscutellum and a narrow yellow line along the posterior margin of the basal segment of the abdomen. _Hab._ Celebes. Fam. TENTHREDINIDAE. Genus TENTHREDO, _Linn._ 1. TENTHREDO (ALLANTUS) PURPURATA. _T._ capite thoraceque caeruleo-viridibus, abdomine purpureo, alis fuscis iridescentibus. Size, length 4 lines. Head and thorax blue-green, abdomen purple; wings dark fuscous with a violet iridescence; an oblique white line on each side beneath the scutellum; legs and antennae black. _Hab._ Celebes. Fam. ICHNEUMONIDAE. Genus MEGISCHUS, _Brulle._ 1. Megischus indicus, _Westw. Trans. Ent. Soc._ new ser. i. 1851. _Hab._ Philippine Islands, Celebes. Genus MESOSTENUS, _Brulle._ 1. MESOSTENUS ALBO-SPINOSUS. _M._ niger, albo varius, abdominis segmentis albo marginatis, metathorace spinis duabus albis armato. _Female._ Length 5-1/2 lines. Black; a half-circular spot on the clypeus, a heart-shaped one above it, a spot at the base of the mandibles, the orbits of the eyes, interrupted at their vertex, yellowish white, the palpi of the same colour, and a broad incomplete annulus on the antennae beyond their middle. Thorax: the mesothorax with two deeply impressed oblique lines inclined inwards and terminating at an ovate spot in the middle of the disk, the scutellum and an oblique line on each side a little before it, a horseshoe-shaped spot in the middle of the metathorax, and a little below it on each side a conical tooth, yellowish white; four spots beneath the wings, one on each side of the metathorax, and the coxae beneath, white; the legs ferruginous, with the intermediate pair dusky behind, the posterior pair entirely so, the femora being black; the wings hyaline, nervures fuscous. Abdomen: punctured and with a white fascia on the margins of the three basal segments; the two apical segments with very narrow fasciae. _Hab._ Celebes. This species is closely allied to the _M. literatus_ of Brulle; but it differs too much, I think, to be identical with it.