304 Transactions. 



palpi tawny, the apical joint with a long yellow bristle below and one 

 apically ; occiput black with a greyish reflection. 



Dorsum of thorax shiny blackish-green to bronzy, with a vestitute of 

 pale hairs ; scutellum shiny bronzy but yellowish apically and clothed 

 with long pale hairs ; pleurae dull cupreous with darker and greyish 

 reflections, and clothed with greyish to brown hairs. Anterior coxae elon- 

 gate and black ; anterior and middle legs brownish, the base of the femora 

 brownish-black, the apex of the tarsi fuscous ; posterior legs brownish- 

 black, particularly the tarsi, the knees lighter ; all the femora with pale 

 hairs beneath on basal half. Wings clear, veins and stigma brown ; a 

 supernumerary humeral cross-vein sometimes present ; the supernumerary 

 vein arising from vein M and already noticed in S. hudsoni (fig. 27) is quite 

 distinct and vein-like in some specimens of S. novae-zealandiae ; halteres 

 pale brown. 



Abdomen (fig. 34) somewhat rectangular, the sides more or less parallel ; 

 dull velvet-black, with a pair of ochreous, cream, orange-red, or white 

 elongate and transverse spots on the 2nd, 3rd, and 4th segments. The 

 variation in the colour of these spots is dependent to a great extent upon 

 the age of the fly ; it is frequently found that some of the spots on the one 

 individual may be of one tint and others lighter or darker ; newly-hatched 

 specimens are semitransparent, the darker colours developing with age. 

 The abdomen is clothed with short and stiff black hairs, with a fringe of 

 silvery ones on each side of basal segment. The genital segments and 

 genitalia are black, and their form is shown in fig. 32. 



$. Eyes dichoptic ; front and vertex shiny blue-black ; antennae 

 black, 3rd joint with a reddish area on lower side at base ; a yellowish- 

 brown area at articulation of antennae. Face with a central shiny blue- 

 black stripe ; an oblique band running from anterior oral margin to orbits 

 as in male ; otherwise face, cheeks and oral margin are brick-red, ochreous., 

 or grey (fig. 31). 



Thorax clothed with pale hairs ; dorsum brilliant cupreous-green ; 

 pleurae and scutellum as dorsum, but the former with dull-black and 

 greyish reflections and the latter diaphanous greenish-yellow apically ; 

 the colour of the scutellum may be lighter or almost totally black. 



Abdomen (fig. 35) rather ovate, with a pair of spots, which vary in 

 colour as in the male, on 2nd, 3rd, 4th, and 5th segments. 



$ and $. Length, 9-11 mm. 



Plesiotype : No. 1235, D. M. 



Habitat. — Abundant throughout New Zealand, the Kermadec and 

 Chatham Islands ; Hutton states that it has been recorded from Polynesia. 

 The adults are on the wing from spring to autumn in the southern parts 

 of the South Island, but in Nelson, Marlborough, and the warmer parts 

 of the North Island they are to be found in varying numbers throughout 

 the year. The eggs are usually laid singly upon plants, and the larvae 

 (Plate XL VIII, fig. 1) feed upon caterpillars and aphids. 



S. ortas Walker. 



S. ortas Walker, Cat. Dipt. Brit. Mus., p. 585 (1849) ; Hutton, Cat. 

 Dipt. N.Z., p. 43 (1881) ; Trans. N.Z. Inst., vol. 33, p. 41 (1901). 

 S. rectus Nowicki, Mem. Krakauer Akad. Wissen., 2, p. 24 (1875) ; 

 Hutton, Cat. Dipt. N.Z., p. 44 (1881). 



A medium-sized fly with a brilliant bronze-green or blue-green thorax, 

 yellow scutellum, and yellow-spotted brown abdomen. 



