2 3 o G. E. J. NIXON 



Head rather deep from back to front ; radial cell narrow ; hind spurs subequal, 

 two fifths as long as the hind basitarsus ; tergite i slightly narrowed behind, finely- 

 punctate or rugose-punctate ; hind femur entirely dark ; hind tibia yellowish only 

 at base. Ovipositor sheath one and one third times as long as the hind tibia. 

 Australia ......... dissors- group (p. 230) 



B Head in a facial view at least never as transverse as in the dissors-group, usually 

 triangular or subtriangular ; lateral polished field of the scutellum strongly convex 

 in the forwards direction and cutting off between itself and the disc a narrow, 

 parallel-sided furrow (Text-fig. 288) ; edge of vannal lobe beyond its widest part 

 usually concave and here without trace of a hair-fringe or, if more or less straight, 

 then the edge with an occasional, minute, projecting hair. 



Head strongly transverse ; setae of tergites 4-6 reduced more or less to a single 

 row .......... mtmda-group (p. 232) 



The DISSORS-Group 



Key to Species 

 Females 



A Mesoscutum smooth-looking but not polished, having an extremely fine, superficial 

 punctation ; legs extremely slender, segment 3 of the hind tarsus being very dis- 

 tinctly longer than 5 ; outer surface of the hind tibia with very sparse, hardly out- 

 standing spines ; hind tibia yellowish on about basal two-fifths ; antenna very 

 slender, segment 6 being fully twice as long as wide ; head thicker from back to 

 front ; 1st abscissa of the radius and the 1st transverse cubitus angled at their 

 junction, almost right-angled ; 1st abscissa of the discoideus distinctly shorter than 

 the 2nd (Text-fig. 293). 



Wings rather strongly brownish ; form considerably more slender than that of 

 the next species ; length ca. 3-5 mm. without ovipositor . . dissors sp. n. 



Australia: F. C. T., Black Mts., 28.V.1930, 1 $, the TYPE, (W. Rafferty). Type 

 in the British Museum (Nat. Hist.). 



In general habitus, especially as regards the shape of the gaster, this species 

 much resembles spilopterus of the munda-group. 

 B Mesoscutum highly polished but with an indication of vague punctation anteriorly ; 

 scutellum a little shorter and narrower then in dissors ; legs much less slender, the 

 3rd segment of the hind tarsus much more thickly and obviously spinose, the spines 

 more upstanding and giving the tibia a somewhat prickly appearance ; antenna 

 much less slender, segment 16 being about one and one third times longer than wide ; 

 head less thick from back to front ; 1st abscissa of the radius and the 1st transverse 

 cubitus less obviously angled at their junction ; 1st abscissa of the discoideus not 

 shorter than the 2nd ; hind tibia pale on about basal quarter. 



Metacarp shorter in proportion to the length of the stigma than in dissors ; 

 length 2-5 mm. without ovipositor ....... calacte sp. n. 



Australia: Victoria, Melbourne, 1 $, the TYPE ; F. C. T., Brindabella, 

 24.xi.1931, 1 $, (L. F. Graham). Type in the British Museum (Nat. Hist.). 



The ovipositor of this species is almost straight and very thin. The gaster of 

 both calacte and dissors is predominantly dark brown with paler colouring at sides of 

 tergites 1 and 2 and to a less extent 3 . Promicrogaster calacte has much the habitus 

 of species of the vacillatrix '-group, the main difference being in the form of the 

 areolet and the relatively shorter spurs of the hind tibia. 



