280 



darkly infuscate and with violaceous blue iridescence. Clypeus punc- 

 tate, dentate and emarginate, impressed at the apex the true emargin- 

 ation not very deep but distinct. Head and thorax very closely, 

 strongly and deeply punctate. Propodeum reticulately and strongly 

 rugosely sculptured throughout but more particularly so at the sides 

 near the posterior concavity. Abdomen with the first segment strongly 

 and closely punctate, the punctures becoming larger towards the base. 

 Second segment above, strongly raised from the base (tuberculate 

 when viewed dorsally) the highest point being well before the middle 

 of its length; very distinctly and evenly but shallowly punctate; be- 

 neath shining, finely and deeply but not closely punctate, the depres- 

 sion faint and narrow the segment at the sides rising but feebly from 

 the level of the apices of the costae which latter are well developed 

 and at their middle where these meet the base of the depression, 

 long. Length, 7-9 mm. 



2 Clypeus evenly and deeply punctate; apex dentate and slightly 

 emarginate, the emargination distinct; the impression at the apex is 

 less than that in the $ . The puncturation of the head and thorax is 

 generally the same as in the $ excepting that the interstices between 

 the coarse punctures on the mesonotum (which in both sexes is 

 shining), show more definite and more visible signs of being punc- 

 tulate. In the ^ these smaller punctures are only microscopically 

 visible. The propodeum and basal segment of the abdomen are prac- 

 tically of the same general sculpture as the ^ . The second dorsal 

 segment of the abdomen is less raised at the base whilst ventrally it 

 is much more shiny, the costae stronger and longer at the middle, 

 whilst the impression is better defined. The sides of this segment 

 where they meet the apices of the costae are more raised than in the 

 5 . Length, 9 mm. 



HAB. Koolau district, Maui, 1,000-1,200 feet elevation in 

 the lower wet forest. Xot uncommon. Described from a series 

 oi 15S S and 69 9 taken October, 1912, (Giffard), flying 

 over mixed scrub oliia (Metrosideros) and bamboo, in company 

 with 0. nigripennis Holmgr., 0. purpurifer P., and 0. came- 

 linus P. A single specimen of 0. erythrostactes P. was taken 

 at the same place. Both types in the collection of the author. 

 OBS. Evidently allied to 0. hiloensis Perk, and 0. lonanus 

 Perk., and whilst like these superficially is readily distin- 

 guished from 0. konanus by the difference in the characters 

 of the propodeum and the second ventral segment of the abdo- 

 men. From 0. hiloensis it particularly differs in the emargin- 

 ation of the clypeus, the length of the costae and general ap- 

 pearance of the second ventral segment. In 0. hiloensis the 

 second dorsal segment of the abdomen is also much more tuber- 

 culately raised than in this species. In the 9 there are further 



