3M M. W. R. de V. GRAHAM 



longer with its median carina fine but distinct ; callus with only three bristles ; 

 speculum of fore wing extending only as far as the end of the proximal third of the 

 marginal vein ; area between postmarginal and stigmal veins mainly hairy ; about 

 the distal third to a half of the basal cell hairy ; stigma more subcircular ; ovipositor 

 sheaths slightly more exserted, to a length varying from three quarters, to slightly 

 more than the whole length, of the hind tibia ; antennal funicle proximally a little 

 stouter, the funicular segments a little shorter, 1-2 quadrate, 3 very slightly trans- 

 verse, 4 and 5 slightly transverse, clava slightly longer, about equal to the three 

 preceding funicular segments together. 



Gastrancistrus crassus Walker 



Gastrancistrus crassus Walker, 1834 : I 77. 6* ?• 



Type material. Syntypes, 7 specimens (but possibly 2 are not original material). 

 LECTOTYPE, a female bearing a printed label " crassus W.", also one in C. 

 Ferriere's handwriting " Type C.F.". 



Britain, Ireland, uncommon ; I have swept it in rough grassy fields and damp 

 meadows. 



Biology. Unknown. Imagines June-August. 



Gastrancistrus hemigaster sp. n. 



(Text-fig. 255) 



$. Head and thorax dark green or bluish green, with brassy and bronzy tinge in places ; 

 gaster bronze, slightly greenish at sides and apex. Antennal scape blackish with a metallic 

 tinge ; pedicellus and flagellum fuscous. Coxae concolorous with the thorax ; trochanters 

 mainly dark ; femora, except their tips, black with a metallic gloss ; tibiae brownish, their 

 bases and tips paler ; fore tarsi mainly fuscous, mid and hind tarsi dull testaceous proximally 

 and fuscous distally. Tegulae brownish testaceous ; wings subhyaline, venation fuscous. 

 Length 1-35 to 1-45 mm. 



Head hardly 1-2 times as broad as the mesoscutum, in dorsal view appearing strongly trans- 

 verse, but as the frons usually collapses, the overall length cannot be measured accurately ; 

 temples rounded off, hardly one fifth as long as the eyes ; POL about 1 -8 OOL, ocelli in a very 

 obtuse triangle. Head in front view oval, hardly 1-2 times as broad as high. Eyes separated 

 by about 1 -3 times their length. Malar space slightly more than one third the length of an eye. 

 Breadth of oral fossa about 3-5 times the malar space. Clypeus about 2-5 times as broad as 

 long, its anterior margin produced and curved but almost truncate medially, much as in vagans 

 (cf . text-fig. 260) . Mandibles rather long and narrow, not falcate, their teeth decreasing gradually 

 in length from the outer one. Head shiny, with fine delicate, hardly raised, sculpture. Antenna 

 (Text-fig. 257) with scape distinctly shorter than an eye ; combined length of pedicellus and 

 flagellum slightly less than breadth of head ; pedicellus about 1-7 times as long as broad, 

 distinctly longer than the first funicular segment ; funicle proximally hardly stouter than the 

 pedicellus, but thickening distad so that the flagellum is fairly strongly clavate ; first funicular 

 segment subquadrate, the following segments more or less transverse, the distal ones strongly 

 so ; clava hardly twice as long as broad, its length about equal to that of the three preceding 

 funicular segments together ; sensilla of funicle relatively sparse. 



Thorax (Text-fig. 255) about 1-5 times as long as broad. Mesoscutum about i-8 times as 



