54 BRITISH ICHNEUMONS [Ther silochus 



wanting; basal area elongate-quadrate, petiolar area extending beyond 

 centre; pleurae finely and alutaceously rugose, not punctate; sternauli 

 wanting. Abdomen short fusiform, little compressed, immaculate black; 

 basal segment little curved, discally subdeplanate, with postpetiole apic- 

 ally explanate ; second segment transverse ; terebra stout, shorter than 

 first segment and apically strongly reflexed. Legs somewhat stout and 

 testaceous with coxae black ; hind femora and sometimes anterior subin- 

 fuscate. Wings hyaline with stigma large and piceous, tegulae flavidous ; 

 apical abscissa of radius straight and at least double length of basal, 

 which is emitted from centre of stigma, with its branch not extending 

 to apex of wing; recurrent nervure emitted beyond the areolar, nervellus 

 vertical. Length, 3 mm. 



Originally described from English material in the Banks Collection. 

 Belgium in May and September, Lapland, Sweden, etc.; bred by Ferris 

 from Tischcria angiisticolcUa in France. Fitch records two males bred 

 from galls of Cynips Kollari (Entom. 1880, p. 257); and Bignell raised it 

 on 6th April from Micivpteryx unimacnleUa in Devonshire. This species, 

 as I understand it, is the most fragile though not the smallest of the 

 genus in Britain, always with an immature appearance; it is very similar 

 to T. niorionelliis, though at once known, superficially by its clear testa- 

 ceous legs and antennal base, particularly by'the 20-jointed female and 

 22-jointed male flagellum, which in the latter is subelongate. In my 

 experience it occurs only from 17th August to 14th September; I possess 

 two batches, each comprising both sexes : one was captured by Beaumont 

 at Harting in Sussex in 1899 and the other was swept from reeds in salt 

 marshes at South wold on the Suffolk coast in September, 1907 and 19 10, 

 when it occurred in considerable numbers; together with a solitary female 

 at light on the pier therein 19 12. Three males swept from sallow in 

 Wicken Fen, Cambs., during June, 1902, appear to belong to this species. 



