following segments black; the base rugose, the second segment finely
punctured, the rest much more strongly so.

_Hab._ Aru.

Group SOCIAL WASPS.

Fam. VESPIDAE, _Steph._

1. ISCHNOGASTER IRIDIPENNIS. _I._ rufescenti-fuscus flavo varius;
vertice et metathorace nigris, alis subhyalinis et pulcherrime
iridescentibus.

_Male._ Length 7-1/4 lines. Head yellow, above the insertion of the
antennae black; antennae black, with the scape, basal joint of the
antennae, and the mandibles ferruginous; the flagellum obscurely
ferruginous beneath; the clypeus produced at the apex into an acute
tooth. Thorax pale ferruginous; the metathorax black, with a ferruginous
spot on each side in front; the scutellum with a reddish-brown spot in
the middle, the postscutellum yellow and subinterrupted in the middle;
the sides of the thorax yellow anteriorly, the yellow portion with two
black spots; the legs slightly variegated with yellow; wings subhyaline
and brilliantly iridescent, the marginal cell with a fuscous cloud.
Abdomen brown; the petiole pale testaceous at its apex and ferruginous
beneath, longer than the head and thorax; the second segment has a
yellow macula on each side, and, beneath, a smaller spot on each side in
a line with the side spots; the first segment has its basal portion
yellow beneath, and a blackish spot in the centre rather behind the
middle.

_Hab._ Aru.

This species in many particulars agrees with the _I. nitidipennis_ of
Saussure, but differs in too many, I think, to be considered the same
species; the second recurrent nervure is straight at the upper
extremity, then curved towards the margin of the wing, and again
straight at its lower extremity; the third submarginal cell is much
wider than the fourth.

Gen. ICARIA, _Sauss._

1. Icaria maculiventris, _Sauss. Mon. Guepes Soc._ p. 23. 1.--Rhopalidia
maculiventris, _Guer. Voy. Coq. Zool._ ii. pt. 2. _Ins_. p. 267, pl. 9.
fig. 8.

_Hab._ Aru; New Guinea.

2. ICARIA NIGRA. _I._ nigra; clypeo antice angulato; metathorace concavo
et transversim striato; alis hyalinis.

_Female._ Length 6 lines. Black, punctured and opake; the clypeus
terminating in a sharp-pointed angle; the base and apex of the mandibles
rufo-piceous; the scape ferruginous in front; the face with a thin,
fine, griseous pubescence. Thorax slightly margined in front; an obscure
testaceous spot on each side of the postscutellum, the metathorax
concave and transversely striated; wings