In the female the flagellum of the antennæ is formed by six quite distinct short joints; the last one, however, is longer, and may consist of two fused together. The second posterior cell is shortly petiolate. Sub-family Odontomyinæ. Abdomen broad, apparently with only five segments. Genus Odontomyia, Latreille (1809). First joint of the antennæ longer than the second, but not elongated; the third fusiform, with five rings and a short style. Eyes contiguous in the male. Scutellum with two spines. Veins of the wing faint towards the posterior margin; generally with four posterior cells (three in the New Zealand species). Key to the Species. Abdomen bordered with green. Spines of the scutellum well developed.   Antennæ black.     Base of scutellum black.       Length, 10–12 mm. O. atrovirens.       Length, 8–10 mm.         Hairs on sides of thorax gray, or none O. chloris.         Hairs on sides of thorax tawny O. chathamensis.       Length 6–8 mm. O. collina.     Scutellum green or tawny O. fulviceps.   Antennæ yellow O. australiensis. Spines of scutellum obsolete; length, 7 mm. O. dorsalis. Abdomen black O. angusta. The females can be distinguished by the outline of the black on the vertex, as follows:— Black on the vertex, convex in front. Length, 10–12 mm. O. atrovirens. Length, 6–8 mm. O. collina. Black on the vertex, notched in front O. chloris. Black on the vertex, concave in front. Length, 9–11 mm. O. chathamensis. Length, 6–7 mm. O. dorsalis. Black on the vertex, confined to the ocellar triangle O. fulviceps. Odontomyia atrovirens. Odontomyia atrovirens, Bigot, Ann. de la Soc. Ent. de France, 5th série, tome ix., page 214 (1879). ♂. “Antennis basi nigris (segmentum tertium ?); facie testaceo fulvo, utrinque albido villosê; haustello nigro; thorace nigro cinereo et parcè villoso, pleuris testaceis, albido villosis; scutello prasino, basi nigro, spinis testaceis; abdomine prasino, supernè nigro nitido late vittato, vittê parum crenatê; halteri-bus prasinis; pedibus testaceis, femoribus anterioribus pallide castaneis, retrorsum, apice fuscis, tibiis basi tarsique parum infuscatis; alis hyalinis, stigmate testaceo” (Bigot).