218 M. W. R. de V. GRAHAM 



Gaster at most twice as long as broad, not or hardly longer than the thorax ; 

 if as much as twice as long as broad, then basal tergite occupying nearly or 

 quite half the total length, and petiole not transverse. Combined length of 

 pedicellus and flagellum 1-15 to 1-5 times breadth of head ; sixth funicular 

 segment usually longer than broad, rarely quadrate. Head and thorax 

 varying from bronze-green through green to violet-blue. Gastral petiole 

 usually as long as or longer than broad, only occasionally transverse. . 3 



3 (2) Both mandibles with four teeth. Antenna with first funicular segment not 



or hardly longer than the pedicellus, the latter (in dorsal view) i-6 to 1-7 

 times as long as broad ; scape entirely blackish, or at most pale at the 

 extreme base. POL slightly greater than OOL. Gastral petiole 1-7 to 

 2 times as long as broad, its sides virtually parallel. Small species, 2-2 mm. or 

 less ; legs relatively dark, the tibiae usually more or less infuscate, sometimes 

 almost entirely so. Gaster shorter than thorax, 11 to 1-5 times as long as 

 broad. Stigma of fore wing nearly as high as long, tending to be sub- 

 circular or subrectangular in shape . . . tumidus (Walker) (p. 221) 



Left mandible with three teeth, right mandible with four. Antenna with first 

 funicular segment distinctly longer than the pedicellus, the latter usually less 

 than i-6 times as long as broad ; scape at least broadly pale at base, 

 sometimes wholly pale. POL about equal to, or even a little less than, OOL. 

 Species often larger ; tibiae often wholly pale, rarely heavily infuscate. Gaster 

 sometimes rather longer. Stigma of fore wing sometimes differently shaped 4 



4 (3) Gastral petiole (Text-fig. 171) with the main, sculptured portion raised above 



the basal stalk, and bounded anteriorly by an arcuate crest. Large species, 

 2-7 to 3-6 mm. Stigma of fore wing at least slightly longer than high, 

 tending to be subtriangular in shape. Scutellar frenum more coarsely 

 sculptured than the rest and usually with some longitudinal carinulae 



scaposus Thomson (p. 220) 



Gastral petiole with the main, sculptured portion not bounded anteriorly by 

 a raised crest. Species sometimes relatively smaller, or with stigma differ- 

 ently shaped ........... 5 



5 (4) Gastral petiole about twice as long as broad, reaching to level of tips of hind 



coxae. Thorax only moderately arched dorsally ; metanotum and 

 propodeum sloping at an angle of 45 or less relative to the plane of the 

 mesoscutum and scutellum ; propodeum medially weakly sculptured and 

 shiny. Antenna (Text-fig. 172) with combined length of pedicellus and 

 flagellum 1 -5 times breadth of head ; funicular segments relatively long 

 (the first 2 to 2-2, the sixth i-6 to 1-75 times, as long as broad) 



lamprosomus sp. n. (p. 222) 



Gastral petiole at most 1 -7 times as long as broad, at least not quite reaching 

 the level of the tips of the hind coxae. Thorax more strongly arched 

 dorsally ; metanotum and propodeum sloping more steeply. Antenna with 

 combined length of pedicellus and flagellum 1-15 to 1-25 times breadth of 

 head ; funicular segments relatively shorter (the first i-6 to 1-9, the sixth 1 

 to 1 -5 times, as long as broad) ........ 6 



6 (5) Fore wing with stigma fully as high as long, tending to be subrectangular or 



subcircular in shape. Large species, 2-7 to 3-2 mm. Scutellar frenum 

 reticulate, without evident longitudinal carinulae . gibbus (Walker) (p. 220) 



- Fore wing with stigma at least slightly longer than high, often more sub- 



triangular in shape. Smaller species, at most 2-5 mm. Scutellar frenum 

 less uniformly sculptured, most often with some longitudinal carinulae as 

 well as reticulation ..... groschkei Delucchi agg. (p. 221) 



