330 BRITISH ICHNEUMONS. \_Mesflchorus 



9 face pale ; cheeks short. Antennae as long as body, rufescent and in 

 $ apirally infuscate. Thorax of 9 piceous or nigrescent, mesonotum 

 rufescent with three dark vittae, of S testaceous with three mesonotal 

 vittae and part of metanotum piceous ; metathorax with complete upper 

 areae. Scutellum of 9 rufescent. Abdomen piceous with first segment 

 basally whitish, second with testaceous and in ^ paler apical margin, 

 third nearly entirely whitish flavous, as are the two following apically and 

 anus nearly entirely; basal segment little curved, with petiole slender and 

 postpetiole sulcate. Legs somewhat stout and whitish flavous, with 9 

 femctra subrufescent ; hind coxae sometimes dark-marked, with their 

 tibiae apically and all the claws nigrescent. Stigma large and black with 

 base and apex whitish, tegulae pale flavous ; radial nervure apically nearly 

 straight ; areolet emitting recurrent nervure a little before its centre ; 

 basal nervure continuous. Length, 5-7 mm. 



This is similar to his Swedish I\f. albipcs, says Thomson, but with the 

 cheeks and calcaria shorter, the stigmal colour determinate and the 

 mesonotum whitish testaceous with three infuscate olivaceous marks ; 

 Schmiedeknecht adds that the scutellum shows traces of an apical 

 granule. 



North and central Europe ; frequent in Thuringia, usually in shady 

 places; and bred by Brischke from I\Jicrogaslej-?,^ec\e?,'n\ CnciiUia argcnfea 

 and from Microgaslcr cocoons in larvae of Sincrinfhus popidi and Amphy- 

 dasis biiularia, as well as from RJiogas species in larvae of Por/hesia auriflua 

 in Prussia. With us it was captured by Norgate at Earlham and Sparham 

 in Norfolk ; bred by Cross — probably at Ely — from Acronycta ligtistri 

 (Kridg. Trans. Norf. Soc. 1894.) and by Norgate from Orgyia anliqiia 

 (Trans. Ent. Soc. 1886, p. 353; ascribed in error by Schmiedeknecht to 

 71/. s/igmaficits, Brisch., which is not yet known to be British). 



20. pectoralis, Ratz. 



Mcsoclionis pectoralis, Ratz. Ichii. d. Forst. i. 149, ii. 110; Holmgr. Sv. Ak. 

 Handl. 1854, p. 59 ; //&. c;Y. 1858, p. 129 ; Brisch. Schr. Nat. Ges. Danz. 1880, 

 p. 181: Thorns. Ann. Soc. Fr. 1885, p. 341, <? 9 . 



Small and black, with the legs rufescent and the hind ones black- 

 marked. Head with the ocelli not large, mandibles constricted towards 

 their apices, cheeks compressed and not elongate, at least the inner 

 orbits rufescent; face except sometimes above, mouth, clypeus and genal 

 apices, flavidous. Antennae black, with the flagellum elongate, slender 

 and filiform. Thorax somewhat coarctate and black with prothorax 

 sometimes rufescent, and the pleurae and sternum rarely red-marked ; 

 petiolar area a little longer at centre tiian at sides. Abdomen compressed 

 towards anus, black with disc of third segment and apical margin of the 

 second rufescent; postpetiole usually sulcate and the two following seg- 

 ments sub(juadrate ; terebra as long as basal segment. Legs somewhat 

 deep red with the anterior basally whitish ; hind coxae, apices of tibiae 

 broadly and their base, with the slender tarsi, nigrescent ; claws and 

 pulvilli small. Wings hardly infumate, with stigma somewhat broad, 

 nigrescent; tegulae wliitish; areolet not large, emitting recurrent nervure 

 from its centre ; radius apically curved. Length, 5-6 mm. 



This and Jl/. iachy/>iis differ from the five last-described in having the 

 hind tarsi nigrescent or obscurely infuscate, the thorax black and the 9 



