PTEROMALIDAE OF N.W. EUROPE 21 



Hind tibia often with only one apical spur, if with two then both are straight ; 

 hind coxae rarely so long as in the above ; middle segments of gaster most 

 often without conspicuous piliferous punctures, without transverse bands 

 of sculpture resembling those of Ormyridae ; marginal vein of fore wing 

 often relatively shorter and the stigmal relatively longer ; antennal formula 

 often otherwise ; postspiracular sclerite rarely fused with the mesopleuron 36 



(35) Hind coxae greatly enlarged (much as in Text-fig. 29) and almost laminar ; 



hind tibiae with a row of about four to six long bristles on their dorsal edge, 

 and a series of about four others on their external surface, with two 

 long apical spurs ; fore wing with one to three isolated bristles on the 

 membrane below the apex of the submarginal vein; antennae with nine 



segments ELASMIDAE (part) 



Hind coxae neither so greatly enlarged nor so strongly flattened ; hind tibiae 

 without specialized series of long bristles, often with only one apical spur ; 

 the other characters usually different ....... 37 



(36) Thorax (Text-fig. 27) : axillae not distinctly marked off from the scutellum, 



the two together forming a transverse band ; propodeum with a triangular 

 median area ; gaster sessile, its basal segment as broad as the propodeum ; 

 antennae five to seven-segmented, with scape, pedicellus, two to four anelli, 

 and a long undivided clava. Fore wing (Text-fig. 28) with fringes from one 

 third to more than half the breadth of the wing, stigma rudimentary. 

 External edge of mid tibia (Text-fig. 30) often with two to four long strong 

 bristles ; mid tarsi sometimes much longer than mid tibiae SIGNIPHORIDAE 

 Thorax : axillae distinctly marked off from the scutellum ; propodeum with- 

 out such a triangular median area ; gaster most often petiolate or sub- 

 petiolate with its basal segment at least slightly narrower than the 

 propodeum ; antennal formula nearly always otherwise .... 38 



(37) Antennae with three to nine segments. Postmarginal vein of fore wing 



usually absent or represented by a short stub, only occasionally as long as the 

 stigmal vein ........... 39 



Antennae with 10 to 13 segments. Postmarginal vein of fore wing usually 

 well-developed and as long as or longer than the stigmal vein, occasionally 

 shorter, but rarely absent ......... 40 



(38) Gaster subsessile, the petiolar segment, if present, transversely linear and not 



easily visible ; postphragma extending at least slightly, often far, into the 

 gaster. Postmarginal vein of fore wing at most about one sixth the length 

 of the marginal vein, but usually less. Pronotum very short and strongly 

 transverse. Scutellum at least slightly, often strongly, transverse 



APHELINIDAE (part) 

 Gaster petiolate, the petiolar segment, even if very short, clearly visible. 

 Either the postmarginal vein is at least one quarter the length of the 

 marginal vein ; or else the gastral petiole is conspicuous, rectangular, and 

 reticulate, and the pronotum is large, longer than the mesoscutum . . 40 



(39) Propodeum extensively pilose : its median third with several hairs which 



converge towards the median line and leave at most a narrow strip down the 

 middle uncovered ; antennae with 11 segments of which six are funicular 

 segments ; hind edge of basal tergite of gaster very convex, so that in some 

 aspects it appears as if a rather deep groove is present between it and the 

 second tergite ; spur of fore tibia weak and straight ; fore wing without a 

 speculum ; pronotum from nearly as long as, to longer than, the meso- 

 scutum ; scutellum with four long bristles. (Females of Tetracampinae) 



TETRACAMPIDAE 



