Stenomacrus | BRITISH ICHNEUMONS. 7% 

coarsely aciculate, third smooth and badious; venter and 9 anus fulves- 
cent; terebra slightly reflexed. Legs normal and entirely fulvous with 
only the tarsi apically infuscate. Wings ample and hyaline with the 
radius infuscate; stigma, radix and tegulae stramineous; areolet wanting, 
and second recurrent emitted from the cubital nervure nearer the sub- 
marginal than the length of the latter. Length, 3—44 mm. 
Amongst the largest of the species with no areolet and larger than the 
following two, with which alone it shares the approximate recurrent 
nervures; and known by its pubescent abdomen, ample wings, and the 
emission of the apically nearly straight radial nervure from almost before 
the centre of the pale stigma. 
It is said to be not very common in Lapland and Sweden. Marshall 
introduced it as British in his 1870 Catalogus on the strength of a g of 
the maximum size, which he captured at Govilon in Monmouth, and | 
have examined in the British Museum; it is certainly rare with us since I, 
too, have found but a single @, by sweeping in a marsh at Henstead near 
Lowestoft on 26th August, 1898. Giraud says (Ann. Soc. Fr, 1877, p.408) 
that he bred this species from the Dipteron Sczara nigripennis, probably in 
Austria. Halliday, in his Dublin Museum MS., claims to have taken it 
commonly in Ireland. 
9. ventralis, Holmgr. 
Orthocentrus ventralis, Holmgr. Sv. Ak. Handl. 1855, p.338,?. O. vittatus, 
Holmer. loc. cit. p. 339; Brisch. Schr. Nat. Ges. Danz. 1878, p. 109, ¢ ; Schr. Ges. 
Konig. 1871, p.102,¢ 9. Stenomacrus ventralis, Thoms. O. E. xxii. 2437, ¢ ?. 
An infuscate-testaceous and somewhat slender species. @. Head 
transverse and shining, very slightly constricted behind the eyes; frons 
subconvex, very smooth and a little impressed in front; face normally 
prominent, punctulate and red or badious; mandibles and palpi pale. 
Antennae slender, filiform, testaceous beneath and somewhat shorter than 
the body; basal flagellar joint conical and elongate, as long as the next 
two. Thorax somewhat narrower than head and black or badious with 
the prothorax and sternum more or less broadly ferrugineous; mesothorax 
convex, finely punctate and pubescent; metathorax discally smooth; 
petiolar area entire and basally emitting carinae, which represent apex of 
the wanting areola. Abdomen deplanate, oblong fusiform and a little 
longer than the head and thorax, with the anus not compressed; basal 
segment broad and a little dilated apically, finely scabriculous or aciculate, 
impressed laterally beyond its centre, and distinctly bicarinate nearly to 
its apex; second transverse and sculptured like the first but with no 
carinae, the thyridii distinct and rufescent, and the apical margin sub- 
testaceous; third alutaceous and badious; the following testaceous and 
the concealed terebra very short and black; venter whitish. Legs slender, 
rufescent-testaceous with trochanters paler and apices of hind femora 
sometimes black-marked. Wings hyaline with stigma and nervures pale, 
tegulae whitish; radial nervure apically arcuate; areolet wanting and 
recurrent nervures approximate. Length, 3 mm. 
The ¢ differs only in its more slender outline and colouration, which is 
testaceous or fulvescent-flavous throughout with only the vertex, nearly 
whole of frons, three indefinite mesonotal vittae, base and apex of abdo- 
men nigrescent, the antennae apically infuscate, and coxae and trochanters 
whitish. 
