192 M. W. R. de V. GRAHAM 



15 (14) Larger species, 2-4 to 3-3 mm. ; head in dorsal view (Text-fig. 160) 2-2 to 2-4 



times as broad as long. Combined length of pedicellus and flagellum about 

 i-6 times breadth of head. Thorax 1-85 to 2 times as long as broad 



breve Walker (p. 203) 



- Smaller species, mostly 1-5 to 2-2 mm. ; rarely (some caledonicum) as much 



as 2-4 mm., in which case the head in dorsal view (Text-fig. 159) is only 

 2-05 to 2-1 times as broad as long, and the combined length of pedicellus 

 and flagellum is 1-65 to 1-75 times breadth of head .... 16 



16 (15) Head in dorsal view (Text-fig. 159) only 2-05 to 2-1 times as broad as long, 



with temples about one third as long as eyes . caledonicum sp. n. (p. 195) 



- Head in dorsal view (Text-fig. 161) about 2-2 times as broad as long, with 



temples only about one quarter as long as eyes . . . . . 17 



17 (16) Antennal scape (Text-fig. 163) more strongly expanded distally, the shiny boss 



extending about two thirds down the scape ; hairs of flagellum standing 



out at an angle of 45 to 6o° .... diffine (Walker) (p. 200) 



Antennal scape less strongly expanded distally, the shiny boss extending only 

 about half way down ; hairs of flagellum standing out rather less strongly 

 than in diffine ....... alpestre (Ruschka) (p. 200) 



18 (3) Antennal scape only slightly expanded distally, the shiny boss indistinct ; 



combined length of pedicellus and flagellum only about 1 -45 times breadth 

 of head ; flagellum rather stout, sixth funicular segment about 1-3 times 

 as long as broad. Hind coxae with some hairs on their dorsal surface. 

 Postspiracular sclerite often with a distinct oblique carina which marks off 

 a triangular upper area. Stigmal vein of fore wing only very slightly 

 curved, forming an angle of about 45 with the postmarginal 



convexum (Walker) (p. 206) 



- Antennal scape distinctly expanded distally, the shiny boss large and extend- 



ing from fully half, to two thirds, down the scape ; combined length of 

 pedicellus and flagellum i-6 to 1-75 times breadth of head ; sixth funicular 

 segment 1-5 to i-8 times as long as broad. Hind coxae (except in some 

 breve) bare dorsally. Postspiracular sclerite most often without an oblique 

 carina (occasionally a trace of one). Stigmal vein usually distinctly curved, 

 and usually forming a more acute angle with the postmarginal . . 19 



19 (18) Mid tibiae blackish at apex ; mid tarsi blackish with only the base of their first 



segment pale. Antennal flagellum relatively slender. Median carina of 

 propodeum usually irregular. Hind coxae usually with a few hairs on their 

 dorsal surface ........ breve Walker (p. 203) 



- Mid tibiae testaceous, or at most indefinitely brownish at apex ; mid tarsi 



usually mainly testaceous, fuscous in some laetum, which has the antennal 

 flagellum relatively stouter. Median carina of propodeum usually straight 

 and sharp, rarely irregular. Hind coxae bare dorsally .... 20 



20 (19) Mid femora less slender, about 4-5 times as long as broad. Antennal flagel- 



lum rather stouter ; first funicular segment 2 to 2-3 times as long as broad. 

 Scutellum usually with at least a short median longitudinal impressed line 

 at the base. ....... laetum Walker (p. 204) 



- Mid femora more slender, about five times as long as broad. Antennal 



flagellum rather more slender ; first funicular segment 2-2 to 2-5 times as 

 long as broad. Scutellum usually without (occasionally with an extremely 

 short) median line at the base .... gelanor (Walker) (p. 205) 



