64 



STRATIOMYID.^ 



PACHYGASTRINiE. 



Fia.OO.—rachyg((stpratra<i. x 12. 



Abdomen with only five or six obvious segments. Venation with the 

 lower cross-vein absent, so that the upper branch of the postical vein 

 forms for a long distance the lower margin of the discal cell ; discal cell 

 emitting only two veinlets irrespective of the upper branch of the postical 

 vein ; cubital fork short or absent. Tibiae without any spurs. 



Eyes bare (unless in Artemita, a South American genus). Antennae with the 

 third joint annulated and globular in the European genus, and with a long sub- 

 terminal arista. 



Thoi-ax subquadrate. 8cutellum unarmed in Pachygaster, but armed in some 

 exotic genera. 



Abdomen Ijroad and rounded in Pachjigaster. 



Legs rather short ; tibi;e without any spurs. 



Wings with only two veinlets issuing fi-om the discal cell liesides the upper 

 branch of tlie postical vein, because the small ci'oss-vein is absent and the iipper 

 brancli of the postical vein forms part of the discal cell for a considerable distance. 

 Four posterior cells, all of which are widely oi)en ; anal cell closed long before the 

 wingmargin. Wing-membrane in Pachi/r/aster not rip])led but minutely and densely 

 pubescent. Alula distinct but not much developed. Alar squanuv very little 

 developed ; thoracal pair absent, Halteres with a rather large knob. 



The essential characters of the Pachyjjastrince lie in the small number 

 of abdominal segments, whereby they are distinguished from the Berincr 

 and Xyloinyina: ; in the two veinlets only from the discal cell (irrespective 

 of the upper branch of the postical vein), whereby tbey are distinguished 

 from all except some Berincr and some Stratiomyina' ; and in the total 

 absence of the lower cross-vein, whereby they are distinguished from the 

 Sargince and Stratiomyina: ; beyond these characters Pachygaster is 

 distinguished from all except the Sargina: by the long subterminal arista. 



The Pachyga^tr'nuv comprise about twenty genera from nearly all parts 



