margin produced on each side as a tubercle, the dorsal surface densely clothed with a short ferruginous pile and the vertical surface with long and delicate brownish hairs. Pleurae black, clothed with black hairs but bare above the coxae; a reddish spot in some lights beneath the wings; anterior and posterior stigmata tawny to orange-red, and protected by a palisade of erect closely-set hairs. Wings clear but blackish-brown at the base; veins and stigma brown, the cubitus and medius paler basally; cell R₁ open; vein R_{4 + 5} deeply curved into cell R₅; cross-vein r-m just beyond the middle of cell 1st M₂; vena spuria indistinct basally, connected with R_{4 + 5} by a distinct cross-vein (absent in some wings) from the nodule; supernumerary vein of cell Cu₂ very distinct and vein-like; squamae and anti-squamae blackish and translucent, the former fringed with long branched pale hairs, the latter with shorter hairs; halteres dark brown but reddish along lower edge. Legs blue-black and bristly; coxae clothed with black hairs; knees orange-yellow; underside, apex, and base of tibiae ferruginous or altogether golden; an orange-yellow area on lower side of posterior tibiae in the middle; anterior and middle femora with dense black hairs below; posterior femora (fig. 64) thickened and with a distinct swelling below, along which are distinct bristle-like hairs; anterior and middle tibiae less bristly than the posterior; the lighter area on lower side of posterior tibiae bare to the apex; tarsi orange-yellow to golden with darker reflections, each joint with short rigid bristles at anterior angles; pulvilli and claws pale tawny, the latter black at the tips; empodium styliform.

Abdomen (fig. 65) black, a shiny blue-black area at anterior margin on each side of 3rd and 4th segments, the apical segment shining and greyish in some lights; broadly ovate, broader than the thorax, clothed with delicate short black bristles, which become dense and stronger along the sides of the 2nd and 3rd segments; 1st segment and an elongate anterior area on each side of the 2nd segment densely clothed with long silvery hairs; when vestiture is removed these bearded areas are testaceous or tawny in ground-colour; a pair of triangular white discal spots and a pair of lateral circular ones on the 3rd and 4th segments and a pair of triangular white spots on the anterior angles of 5th segment as shown in fig. 65; from the sides of the 4th segment are long hairs, black except those from the lateral spots which are white; ventrally the abdomen is sparsely clothed with grey hairs; the basal sternite greyish and transversely rugose, the remainder blue-black; a pair of short orange-red styles project from apical segment.

• Fig. 25.—Syrphus hudsoni n. sp.: dorsal view of head of male.

• Fig. 26.—S. hudsoni n. sp.: outline of head in profile.

• Fig. 27.—S. hudsoni n. sp.: part of venation, showing origin of vena spuria, &c.

• Fig. 28.—S. hudsoni n. sp.: diagram of abdomen of male.

• Fig. 29.—S. novae-zealandiae: antenna.

• Fig. 30.—S. novae-zealandiae: outline of head in profile of male.

• Fig. 31.—S. novae-zealandiae: outline of head in profile of female.

• Fig. 32.—S. novae-zealandiae: genitalia of male.

• Fig. 33.—S. ortas: outline of head in profile.

• Fig. 34.—S. novae-zealandiae: diagram of abdomen of male.

• Fig. 35.—S. novae-zealandiae: diagram of abdomen of female.

• Fig. 36.—S. ortas: diagram of abdomen of female.

• Fig. 37.—S. ropalus: diagram of abdomen of female.

• Fig. 38.—Melanostoma fasciatum: outline of head in profile.

• Fig. 39.—M. fasciatum: diagram of abdomen of male.

• Fig. 40.—M. fasciatum: diagram of abdomen of female.

• Fig. 41.—M. fasciatum: antenna.

• Fig. 42.—Platycheirus lignudus n. sp.: outline of head in profile.