BY FRANK H. TAYLOR. 813 



Wings hyaline, veins dark; stigma light amber, elongate; 

 squamae creamy; halteres with the stem ochraceous, the knob 

 black. 



Ilab. — Batchelor, Staplebon, Northern Territory (G. F. Hill; 

 No.35). 



Described from specimens forwarded to the Institute by Mr. 

 Hill. This is a somewhat elongate species, and most nearly 

 allied to S. australis Ricardo. Cotype in Coll. Hill. 



SiLVIUS TABANIFORMIS, Sp.n. 



9. Length, 10; width of head, 4; width of front at vertex, 0*5; 

 length of wing, 9 mm. 



Head: face grey, with a scanty, grey beard; front black, och- 

 raceous between the frontal and subcalli, the former black, pear- 

 shaped, tumid, shiny; subcallus shining-black; first and second 

 segments of antennae dull golden, the first with prominent, black, 

 apical hairs, third segment light testaceous, base broadly tri- 

 angular, annuli brown; palpi light testaceous, about two-thirds 

 the length of the proboscis, the latter pitchy black; eyes deep 

 greenish-black, the inner margins slightly converging towards 

 the base; ocelli black. 



Thorax black, clad with numerous, appressed, golden hairs; 

 pleurae black, clothed with grey hairs, fairly long at the wing- 

 roots; scutellum similar to thorax. 



Abdomen black, anterior portion of tirst and second segments 

 light brown, posterior margin of all segments brown, clothed 

 with pale hairs, and a small, median, apical patch of pale hairs, 

 giving the segments a striped appearance; venter with the first 

 three segments mummy-brown, the remainder dark brown 



Wings hyaline; veins dark brown; stigma elongate, incon- 

 spicuous, pale cream ; squamae grey ; halteres brown, knobs 

 creamy. 



Legs : forelegs black, knees and basal two-thirds of tibiae 

 mummy-brown; in the midlegs, the apical two-thirds of femora, 

 the tibiae and first two tarsals mummy-brown, remainder black; 

 the hindlegs with the apical third of the femora, tibiae, and first 

 two tarsals mummy-brown, the rest black, the femora and tibiae 



