Perilissus] BRITISH ICHNEUMONS. 255 

1. filicornis, Grav. 
Ichneumon filicornis, Gr. Mem. Ac. Sc. Torin. 1820, p. 368, ¢.* Mesoleptus 
filicornis, Gr. I. E. ii.94; Ste. Ill. M. vii. 227; Blanch. Hist. Nat. Ins. iii. 308 ; 
Fonsc. Ann. Soc. Fr 1849, p.215, ¢ ?. Perilissus filicornis, Holmgr. Sv. Ak. 
Handl. 1854, p.63; Jib. cit. 1855, p. 121; Voll. Pinac. pl. xxxili, fig.1, ¢ ¢; cf. 
Spanotecnus filicornis, Thoms. O. E. ix. 911. M. seminiger, Gr. I. E. ii. 93, 
@; Ste. Ill. M. vii. 226; P.seminiger, Voll. Pinac. pl. xxxiii, fig. 2; Hadrodacty- 
lus seminiger, Thoms. O. E. ix.921. 
Punctate and a little shining, with all the coxae and usually the 
abdomen red. Head tumidulous, and not constricted posteriorly, closely 
punctate ; frons dull, face slightly convex and very closely punctate ; cly- 
peus not discreted, sparsely punctate, apically rounded and coarsely 
punctate ; ¢ with mouth and clypeus stramineous, mandibles apically 
infuscate and the face rarely badious-spotted or entirely testaceous; 9 
with mouth rufescent. Antennae very slender, distinctly a little longer 
than the body, entirely rufescent, or in g subinfuscate towards their 
apices. Thorax closely punctate, with not very distinct notauli; meta- 
thorax more shining and very distinctly areated with costulae distinct, 
upper lateral areae subquadrate and areola elongate-hexagonal. Scutellum 
subconvex. Abdomen subsericeous and oblong-ovate; more or less 
rufescent from apex of first or of second segment, usually with anus 
infuscate or black, very rarely entirely black with the third segment alone 
badious ; basal segment subconvex, very slightly curved, smooth or 
obsoletely sulcate, with postpetiole slender, hardly explanate, longer than 
broad and fully as long as the parallel-sided petiole ; spiracles distinct ; 
terebra ferrugineous and very shortly exserted. Legs slender, red or tes- 
taceous; hind femora usually entirely or centrally nigrescent or black. 
Wings not small, subhyaline with stigma and radius piceous, the former 
basally paler or entirely testaceous ; radix and tegulae testaceous ; areolet 
suborbicular and a little petiolate, second recurrent nervure nearly half 
pellucid; nervellus very strongly postfurcal, intercepted above centre. 
Length, 6-—9 mm. 
The always present though occasionally fine metanotal costulae, 
strongly postfurcal nervellus and pale hind coxae will distinguish this 
species, the colour of whose abdomen, face and hind femora is extremely 
variable. The var. seminiger differs solely in having the face and cheeks 
pale red. 
It occurs with considerable frequency in northern Europe, in Italy, and 
probably throughout the palearctic region; Brischke alone appears to 
have bred it (Schr. Phys. Ges. K6nig. 1871, p. 69), and he found it 
emerged from larvae of Mematus latipes, of N. fraxint, of N. Lrichsont 
and from those of an unnamed species of Do/erus, in Prussia. This 
species has occurred to me annually since 1898 from 27th May to 4th July 
only, and always by sweeping reeds in very marshy places; it certainly 
cannot be termed common in the eastern counties, since I have not found 
a dozen examples in as many years and it always turns up singly. In 
Suffolk it has been found at Stanstead Wood, Bentley Woods (once in ten 

*I am ata loss to know what Ichneuwmon variator, Mill. (Zool. Dan. Prodr. 1776, 157) may be. 
Gravenhorst regarded it as distinct from J. filicornis in 1820; but synonymous with tis own TZ. 
variator of that date and M. filicornis of 1829. Marshall perpetuated its individuality in 1872 by 
synonymising it only with Gravenhorst’s var. 1 of M. filicornis (pronounced to be nothing but var. 
seminiger by Pfank.) probably on account of Stephens’ description, which looks like a ¢ seminiger, 
from the London district, though no examples are now in his collection. Let it lapse: filicornis is a 
sufficiently appropriate name, 

