6o BRITISH ICHNEUMONS. [Olnsiphaga. 



Thorax normal, with scutellum convex and fully developed ; mesonotum 

 deeply sulcate longitudinally throughout ; notauli distinct and lateral ; 

 nietathorax completely areated, with costulae strong ; areola hexagonal and 

 sub-transverse, petiolar area broadly discreted, with apophyses stout though 

 obtuse. Abdomen sub-ovate, glabrous and very strongly nitidulous ; basal 

 segment dull, evenly explanate throughout, bicarinate and strongly acicu- 

 late, somewhat broad basally and laterally margined apically, its spiracles 

 central and not prominent ; terebra stout and as long as the abdomen. 

 Tarsi slender. \Vings extending to apex of post-petiole, radial cell short 

 and broad, areolet wanting. 



Closely allied to Catalytus in the length and structure of the wings, and 

 to Aptesis. in the stout antennae, but differing' materially from both in the 

 strongly and completely areated thorax, glabrous abdomen, mesonotal 

 sulcus and the elongate terebra, which last two distinctions will instantly 

 distinguish it from all other Ichneumonidae. 



I. stenoptera, Marsh. 



Aplesis stenoptera. Marsh. E.M.M. v. (i86S), p. 156, ?. Hemiteles steiioplerns. 

 Thorns. O. E. x. 985 ; Schm. Term. Euz. 1897, p. 510. 9, 



Head broader than thorax, finely punctulate, sub-coriaceous, black. 

 Antennae infuscate, with the scape and base of the first flagellar joint, 

 which is slightly longer than the second, testaceous. Thorax finely 

 punctulate and sub-coriaceous, black ; areae nitidulous. Abdomen basally 

 black ; apex of first segment, whole of second and often base of the third 

 testaceous ; remainder indeterminately piceous ; spicula red, valvulae 

 infuscate. Legs testaceous, with the apical tarsal joint dark. Wings narrow 

 and not explanate beyond the centre, somewhat infumate ; stigma and 

 radix dull piceous ; areolet irregular, transverse and outwardly wanting, 

 often containing a white spot. Length, 2f mm. 



Marshall says this species is very like Microcryptus brachypterus, but 

 with no flagellar band, black basal segment, longer terebra, and the wings 

 and thorax differ. 



He first took it at Milford Haven, in 1867 and 1868 ; and Botusfleming, 

 in Cornwall (in Brit. Mus.) ; subsequently Bloomfield recorded it (E.M.M. 

 xvii. p. 258) from a sand-pit, in Guestling Wood, near Hastings, in Sep- 

 tember ; and Bignell thrice took it in Devon, in the middle of September, 

 at Slade, Bickleigh and Exeter. Thomson has found it in Sweden. Towards 

 the end of June, 1903, Waterston sent me a female from Edinburgh, 

 together with the host's cocoon from which it had just emerged, remarking : 

 " It is parasitic not on an insect but on an Arachnid, viz., the commonest 

 of our British false-scorpions, Obisiutn juMsconi/n, Leach. The 9 of this 

 species constructs a well-woven cocoon and there brings forth and hatches 

 her eggs, which remain for a month or more attached to the genital pore. 

 As a rule, Ohisium is quite a formidable creature with its strong falces, but 

 during reproduction, and especially in the last phase, it becomes inactive. 

 It is at such a time, I suspect, that this ichneumon makes its attack. I 

 had noticed chitinous fragments in the cocoon, but never saw the pest 



