260 BRITISH [CHNEUMONS. [ Perilissus 

orbiculate and subpetiolate ; nervellus antefurcal, intercepted far below 
centre. Length, s—64 mm. 
It differs from P. erythrocephalus, which it is said to resemble, in its less 
tumidous head, lack of metanotal costulae and shorter basal segment. 
Probably uncommon in northern Europe, and found during May in 
Germany. With us it certainly appears rare and was not introduced till 
1881 (Trans. Ent. Soc. p. 163), when Bridgman noticed an unlocalised 
example from Mr. E. A. Butler’s collection. Marshall once found the 
males ‘‘very rare” at Rannoch; Piffard took a female at Felden; and 
Atmore has sent both Bridgman and me several from his Kings Lynn 
garden, where they occurred during June and in August, 1904. I have 
twice met with the female by sweeping in Tuddenham Fen in Suffolk 
about the middle of June, rgoo, and in early July, rg09, in Matley Bog in 
the New Forest. 
7. triangulatus, Bridg. 
Perilissus triangulatus, Bridg. Trans. Ent Soc. 1886, p. 362, ¢ 2. (?) Meso- 
leptus ventralis, Curt. B. E. 644, ¢. 
A dull species with black hind legs, the abdomen basally red and 
petiole unusually short. Head posteriorly not narrower than eyes; 
mouth, mandibles, clypeus and facial orbits triangularly, testaceous ; cly- 
peus not discreted, cheeks long, face closely and distinctly punctate. 
Antennae as long as body, infuscate with scape and base of the flagellum 
pale beneath ; lower mandibular tooth the longer. ‘Thorax immaculate 
black, with notauli apically distinct and mesopleurae finely punctate ; 
metanotum finely rugose, with the areola elongate or wanting. Scu- 
tellum hardly convex and only basally margined. Abdomen subclavate, 
dull red with only the anus from apex of fifth segment black; basal seg- 
ment short and sulcate to near apex but not carinate, with distinctly 
antecentral spiracles; petiole not broader than long, basally sub- 
constricted ; postpetiole longer than broad, slightly explanate apically, 
coriaceous, apically smooth; terebra slightly exserted. Legs somewhat 
slender ; anterior red with coxae and, except apically, trochanters black ; 
hind legs black with their tibiae broadly in centre, or except apically, 
subbadious. Wings with tegulae whitish; stigma infuscate stramineous, 
basally paler ; areolet small, suborbiculate and petiolate; nervellus sub- 
opposite, intercepted distinctly below its centre. Length, 9 mm. 
I know nothing about this species, the structure of whose face Bridg- 
man says is like that of P. filicorn’s and of whose basal segment is ‘‘ more 
the shape of A/esoleus than Perilissus.” It was described from examples 
taken at Peckham and Dulwich on May 30th, 1885, and has not since 
been noticed. 
There is, however, a male in my collection which I have not the least 
hesitation in referring to Mesoleptus ventralis, Curt. (B. E. 644), so exactly 
agreeing with the above description by Bridgman that I quite expect his 
insect will prove but a colour variety of Curtis’ unlocalised though British 
species. My specimen has the clypeus, flagellum and abdomen except 
the obsoletely badious incisures, black; the facial markings are triangu- 
larly pale and the lower mandibular tooth distinctly the longer; the 
