niiiparsus'] BRITISH ICHNEUMONS. 41 



before the end of August and extending in Hampshire into October. It 

 has occurred to Lyle and me, ahnost always on the flowers of Daunts caivia 

 or Aiigtiica sylvesiris at IMatlev Bog in the New Forest and in Suffolk at 

 Ciaydon Bridge, Barnby Broad, Henstead Marsh, Tuddenliam I''en, 

 Bentlev Woods, Wenhaston marshes and Holbrook, as late as the 24th 

 September. 1 first took the female on the water of a horse-trough in 

 Ipswich; and have obtained males at Chippenham I-'en in Cainhs. ami 

 Ringstead in Norfolk. 



THERSILOCHUS, Hobuiircn. 



Holmgr. Sv. Ak. Hand), 1858, p. 135; Thorns. O.E. xiii. 1378. 



Head not or hardly broader than thorax, extremely finely punctate, and 

 equally rarely with the $ eyes and ocelli very large. Antennae with the 

 flagellum sometimes pauci-articulate. Thorax with notauli obsolete or 

 wanting; basal metanotal area not rarely simply indicated by an elevated 

 costa; sternauli sometimes obsolete or wanting. Abdomen often with 

 the second segment transverse, its thyridii always small and punctiform. 

 Legs with the tibial calcaria small and short. Wings with the branch of 

 the radial nervre very rarely extending to apex of wing ; apical lower 

 angle of the brachial cell sometimes open, i.e., with its nervure wanting ; 

 recurrent nervure very rarely entirely wanting, and not infrecjuently 

 emitted before the areolar nervure. 



I here employ this genus in the sense used by Thomson, separating 

 from Holmgren's genus only those species which were placed by the 

 former in his Biaparsus. Recent Continental authors have raised 

 Forster's divisions into genera and, doubtless, as more and more species 

 are published it may be necessary to thus adopt them, however little 

 stability they contain ; but, at present in Britain, our fauna is not suf- 

 ficiently known to render their retention at all necessary ; for, in reality, 

 their use is as well exemplified in specific as in generic division. I have 

 not placed Pon'zoti fiilTipes, Grav., relegated to this genus by Marshall, 

 because it is known by a single Nuremberg 9 only, and our claims are 

 visionary. 



7ab/c of Species. 



(2). 1 . I )isc()itlal ceil apieallv opL-n, througli 

 the recurrent nervure being in- 

 complete ; metatliorax with basal 

 longitudinal costa in place of 

 basal area ; body small and black, 

 legs dark ; recurrent nervure 

 partly present; head not glitter- 

 ing; terebra shorter than abdo- 

 men (An Kiel, is, />/.) .1. y{\l\.\y.\\<\vs. IIoh)igr. 



(i). 2. Diseoidal cell entire, with recurrent 

 nervine subcomplcte. 



(4). 5. I^yesot' J very large, hemispherical ; 

 temples constricted ; head of V 

 normal ; metapleiiral spiracles 

 remote from mel.iplcur.ir (Al.I.O- 

 IMIKVS, Fsf.) .2. iiooi'S, Grav. 



(3). .\. Eyes of normal si/e in both sexes. 



1)2 



