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. TENTHREDINIDÆ, Leach.
Gen. Oryssus, Fabr.
1. Oryssus maculipennis. O. niger, punctatus; pedibus ferrugineis; alis fuscis fasciâ hyalinâ ante cellulam marginalem sitâ.
Female. Length 5½ lines. Black; the head rugose, the front coarsely so, with a row of transverse tubercles running from the vertex along the inner orbits of the eyes, and crossing the front at half their length; the cheeks with a cinereous down, and a line of silvery-white pubescence or down, along the outer orbits of the eyes. Thorax coarsely punctured; the mesothorax with a central longitudinal smooth elevation; wings fuscous, with a broad transverse hyaline fascia before the base of the marginal cell, the tips of the wings hyaline; the legs ferruginous, with the coxæ and trochanters black; the posterior tibiæ with a double row of serrations outside. Abdomen shining and closely punctured; the base and apex coarsely so.
Hab. Aru.
Gen. Xyphidria, Latr.
1. Xyphidria rufipes. X. nigra; mandibulis, antennarum scapo, pedibusque ferrugineis; alis hyalinis et iridescentibus.
Female. Length 4 lines. Black and shining; the vertex highly polished; the front from the posterior ocelli forwards closely punctured and opake; the mandibles, scape, and basal joint of the flagellum ferruginous. The thorax anteriorly punctured and opake, posteriorly shining, and with a few punctures at the base of the scutellum; wings hyaline and iridescent, the nervures black, the extreme base of the wings and the tegulæ pale testaceous; the legs pale ferruginous, with the claws of the tarsi darker. Abdomen: the base of the segments depressed and very delicately and closely punctured, subopake; the apical half highly polished and shining; beneath obscurely rufo-piceous.
Hab. Aru.