_Female._ Length 6 lines. Head obscure, testaceous yellow; the eyes brown; the antennae black. Thorax and the anterior and intermediate legs ferruginous; an ovate black spot on the metathorax; and the posterior legs black, with the articulations obscurely ferruginous; wings dark fuscous, with the nervures and stigma black, the base of the latter yellowish, and a hyaline streak beneath it, which crosses the first submarginal cell. Abdomen black and shining; the first segment with some coarse striae at the apex; the second with a central forked carina and an oblique one on each side running inwards to the apex of the segment; between the carinae are a number of deep grooves; the lateral margins of the three basal segments carinated; the third segment has a row of short deep striae at its base; the ovipositor longer than the body. _Hab._ Aru. 8. BRACON INTRUDENS. _B._ niger; thorace, pedibus anticis intermediisque et abdominis segmento basali ferrugineis; alis hyalinis. _Female._ Length 5 lines. Black; the thorax, anterior and intermediate legs, the articulations of the posterior pair, and the base of the abdomen ferruginous, entirely smooth and shining; the wings subhyaline, the nervures fusco-ferruginous, an irregular fuscous stain at the base of the first submarginal cell, extending beyond it. Abdomen: the basal segment margined at the sides; the second segment with an oblique deeply impressed line running inwards, not quite meeting or extending to the apical margin. _Hab._ Aru. Gen. AGATHIS, _Latr._ 1. AGATHIS FUMIPENNIS. _A._ ferruginea; capite, abdominis apice tarsisque posticis nigris; alis obscure fuscis. _Female._ Length 4 lines. Reddish-yellow; the head, apical joint of the intermediate tarsi, the apex of the posterior tibiae, and the third and following segments of the abdomen black; the thorax and legs with a thin, short, pale fulvous pubescence; the head and abdomen smooth and shining; the head produced before the eyes into a kind of beak, rufo-piceous anteriorly. Thorax narrowed before the wings, which are dark fuscous, with a hyaline irregular mark below the stigma, crossing the submarginal cell; the anterior margin of the anterior wings pubescent; the metathorax broad, margined laterally, with a central forked carina, and a crooked one on each side; the posterior legs incrassate. Abdomen with the sides of the upper surface carinated. _Hab._ Aru. Fam. CHRYSIDIDAE, _Leach_. Gen. STILBUM, _Spin._ 1. Stilbum splendidum, _Fabr. Syst. Piez._ p. 170. 1. _Hab._ Aru; Senegal; Java; Bengal. 2. Stilbum amethystinum, _Fabr. Syst. Piez._ p. 176. 32. _Hab._ Aru; Australia. Fabricius includes this insect in the genus _Chrysis_; the typical specimen, however, proves that it belongs to the more modern genus _Stilbum_: it is very distinct from _S. splendidum_, being much more strongly and coarsely punctured; and the teeth which arm the apical segment are differently disposed on the margin. Fam. TENTHREDINIDAE, _Leach_.