_Female._ Length 6 lines. Ferruginous; the posterior tarsi and the fourth and following segments of the abdomen black; the head is reddish yellow, the eyes brown; the scape and two or three of the basal joints of the flagellum ferruginous, the rest fuscous; the basal half of the wings flavo-hyaline, the apical half fuscous; the stigma yellow, with a subhyaline macula beneath, and two other similar irregular-shaped spots. The abdomen with two longitudinal carinae on the basal segment, and a transverse curved impressed line on the other segments. _Hab._ Key Island. This species might at first sight be mistaken for a species of the genus _Bracon_. The male only differs from the female in having the abdomen black, with only the basal segment yellow; the wings are only very slightly yellow at their base; it is also rather smaller. 3. PIMPLA PENETRANS. _P._ flavo-ferruginea; flagello fusco; alis flavo-hyalinis, apice fuscis. _Female._ Length 4-1/4 lines. Reddish yellow, smooth, and shining; the face testaceous, with slight fuscous stains; the scape and two or three of the basal joints of the flagellum yellow in front; the wings hyaline, with a yellowish tinge; the nervures black, except the costal nervure, which is ferruginous towards the base, the apex of the wings slightly clouded; the posterior tibiae fuscous above. Abdomen: the segments with slightly impressed oblique depressions, the ovipositor shorter than the abdomen, and black. The _Male_ only differs in having the abdomen rather more slender. _Hab._ Aru. 4. PIMPLA FERRUGINEA. _P._ flavo-ferruginea; antennis supra fuscis; alis hyalinis. _Female._ Length 5-1/2 lines. Ferruginous, with the head and thorax beneath yellow-testaceous; the coxae also are of the same colour; the flagellum slightly fuscous above; the wings flavo-hyaline, the nervures black; the two basal segments of the abdomen shining, the third and the following segments subopake; the ovipositor as long as the abdomen. _Hab._ Key Island. 5. PIMPLA PLAGIATA. _P._ flavo-rufa; antennis strigisque tribus mesothoracis nigris; alis hyalinis, apice cellulae marginalis fusco unimaculato. _Female._ Length 5-1/2 lines. Yellow, the legs with ferruginous stains; the antennae black, with the scape yellow in front; the head with a large ovate black spot behind the ocelli. Thorax finely punctured on the disk of metathorax, which has three longitudinal broad black stripes, a narrow black line on the posterior margin of both the scutellum and postscutellum; wings hyaline, the nervures black, with a dark fuscous spot at the apex of the marginal cell. Abdomen reddish-yellow, with the apical margins of the segments yellow; the ovipositor black, and shorter than the abdomen. _Hab._ Aru. Gen. RHYSSA, _Grav._ 1. RHYSSA MACULIPENNIS. _R._ rufescenti-flava; antennis et vertice nigris; alis hyalinis, plaga nigro-fusca.