324 BRITISH ICHNEUMONS. [Mesochorus 



3Iicrogaster, which agrees exactly with Brischke's description of the 

 above" (Bridg. Trans. Ent. Soc. 1882, p. 154; cf. I.e. 1886, p. 354). Bred 

 in Devon on 6th June horn Abraxas irn>ssu/ar/a/a through ApanleJcs nothus, 

 and on 28th September from iMe/anippc i:;ah'afa ihrovL\:(\\ the same Braconid 

 (Bignell; quoted by Marshall, Bracon. d'Europ. i. 437). Hyperparasitic 

 through A. grossulariata on Exon's/a milgaris (Buckler, vii.). Doubtless 

 very common in Britain ; I have a dozen in Capron's Surrey collection 

 and two from Bignell "hyperparasitic on Scythropia crataegcUa" m Devon; 

 a 9 bred by Slater in November, iqo8, from a Braconid cocoon ex 

 Eupitlncia ? anvnaia; and I have met with it in June at Diss in Norfolk, 

 ]\lar\ell Copse in the Isle of Wight and Brandon in Suffolk. 



12. crassicrus, Thoius. 



Mesochorus olerum, Curt. Brit. Ent. x. 1833, 464; cf. Hal. Ann. Nat. Hist. 

 1839, p. 114, ? (?). M. crassicrus. Thorns. Ann. Soc. Ent. France, 1885, p. 339, 



Black with the abdomen centrally, the orbits and legs, rufescent ; 

 stigma infuscate and front tibiae of 9 subclavate. Head with ocelli 

 somewhat small, the orbits rufescent, cheeks almost longer than mandi- 

 bular base, and the 9 face black. Antennae somewhat stout and a little 

 pilose towards their base. Thorax black. Abdomen not strongly com- 

 pres.sed apically; apex of second segment and nearly whole of the third 

 red, the remainder black with their apices very narrowly pale; terebra 

 short. Legs with base of hind tibiae, and their apices more broadly, 

 nigrescent; hind tarsi pale, unguiculi not narrow. Wings slightly in- 

 fumate, with parallel nervure emitted a little above centre of brachial cell. 

 Length, 6-7 mm. 



Thomson omits the locality of his species and it is very probable that 

 the type was among the examples he named, bred by Fletcher in June 

 from Wicken Fen out of GaJechia notaiella (Trans. Ent. Soc. 1886, p. 353). 

 It is perhaps not imcommon with us, since Capron had a full series from 

 Shere, Stenton has given me males bred from Abraxas grossiilanafa in 

 May, 1907, at Heme Hill near London, and Lyle has raised it hyper- 

 parasitically from 77u'ra variata through a black species of A?iilasfa in the 

 New Forest, 



Bridgman appears to have made up his mind as to what species the 

 Curtisian descriptions, insufficient though they be, represented, for he 

 named Bignell's specimens with several of them. The Curtis collection 

 is in Australia and, in the absence of types, I am less fortunate (or bold). 

 Thus I can but surmise that it be not impossible that M. olerum which, 

 according to Haliday, " may prove to be a variety of i\I. splendidulns," 

 Grav., is a form of the present species. On 30th May in a garden at Laira 

 in Devon, Bignell saw a female of M. olerum flitting about from leaf to 

 leaf, with antennae in constant motion, evidently hunting for a victim. 

 After a time she found a caterpillar of Abraxas grossulariata and, first 

 passing round it several times, " she suddenly sprang on the unfortunate 

 larva, and thrust her ovipositor into the second segment just below the 

 dorsal line; the larva, during the operation, twisted itself from side to 

 side to get rid of the foe." The Ichneumon next alighted on a leaf, very 

 carefully wiped her terebra, and was boxed. The larva pupated on 14th 

 June and Casinaria 7<idua emerged from it on 2Qth. "No doubt M.oleruvi, 

 \\ho is a hyperparasite, having found that the A.gross?i/aria/a was infested 



