102 BRITISH ICHNEUMONS. [ Homocidus 

Thorax gibbous, stout and punctulate; hamate lines before and some- 
times also beneath radices, and in @ base of pleurae lined with, flavous ; 
metathorax rugose with the lateral costae determinate, the basal and 
petiolar areae indicated. Scutellum, and usually apex of postscutellum, 
flavous in both sexes. Abdomen longer than head and thorax, deeply 
punctate, deplanate, black, apically nitidulous and in Q subcompressed ; 
first segment parallel-sided, basally depressed and punctate-rugulose with 
the postpetiole longer than broad, discal carinae parallel, somewhat con- 
spicuous and (sec Desv.) confluent before apex; second not transverse 
with the thyridii oblique, deeply impressed and the intervening space 
strongly strigose (Holmgr.; haud striolata, Thoms.). Legs normal, 
rufescent with hind tarsi and apices of their tibiae black; coxae and tro- 
chanters of 2 partly nigrescent, of ¢ entirely flavous. Wings slightly 
infumate ; tegulae and radices flavous; costa and stigma black, with base 
of the latter pale; areolet triangular, petiolate (Desv.) subpetiolate 
(Holmgr.) or subsessile (Thoms.); radial nervure apically nearly straight ; 
nervellus antefurcal and intercepted a little below its centre. Length, 
8—g mm. 
This species is the largest of all Bass? (sensu lato) and it is at once 
known by its distinct areolet, entirely pale scutellum and scabrous basal 
segments. Desvignes adds that his ¢ has the margins of all the segments, 
and especially the basal ones, tuberculate with three longitudinal furrows 
on the second; the hind coxae and base of their trochanters black; the 
frontal orbits partly, and the cheeks, the mesosternum apically, propleural 
spots and the frenum, flavous. Brischke says his 9 has the base of the 
scutellum black and the hind tibiae mainly flavous, though the latter are 
expressly stated to be pale fulvous by Desvignes ; I am inclined to doubt 
the synonymny of this female. 
I have given a full description of this large species on account of its 
rarity. Only three or four specimens were taken in central and southern 
Sweden by Boheman and Dahlbom (Holmgr. and Thoms.); the female 
in Prussia (Brischke). I have seen the male described by Desvignes in 
the National Collection, and find it entirely synonymous. The only sub- 
sequent mention we have of it as indigenous is Bignell’s record from 
Devon: ‘Captured at Laira, 1oth September” (Trans. Devon. Assoc. 
1898, p. 501). I have never met with this species and its economy is 
quite unknown. 
16. dimidiatus, Schr. 
Ichneumon dimidiatus, Schr. F. B. ii. 293; Gr. I. E. iii, 950, ¢. B. dimidt- 
atus, Holmgr. lib. cit. 363, ¢. B. planus, Desv. Trans. Ent. Soc. 1862, p. 220, 
3 %. Homoporus pictus, Thoms. O. E. xiv. 1511, ¢ ¢. H. dimidiatus, Morl. 
Trans. Ent. Soc. 1905, p. 428, ¢ ¢. 
Head almost broader than thorax, somewhat constricted posteriorly, 
vertex somewhat angularly emarginate; frons nitidulous and not sulcate, 
though impressed above scrobes; face subdilated apically with epistoma 
hardly elevated, of 9 sometimes white-marked; @ with face and cheeks 
broadly, and mouth, pale ; clypeus deplanate, subpunctate with the apex 
obviously emarginate centrally and the sides foveolate ; cheeks almost 
longer than base of the often pale mandibles; palpi infuscate or whitish. 
Antennae black throughout in 9, pale beneath in dg; their apices sub- 
attenuate and flagellum, of about twenty-two joints, reaching beyond 
