160 BRITISH ICHNEUMONS. [ Wesolerus 


“Scarce: found in June at Darenth wood” (Stephens) ; Glanvilles 
Wootton, Dorset (Dale); Cromer and brundall, Norfolk (Bridgman) ; 
examples in the British Museum are from Marsham’s, Stephens’, Des- 
vignes’ and Marshall’s collections, the last (labelled, JZ. formosus) is from 
Bishops Teignton. I have seen it from Sutton, near Birmingham, 1896 
(Bradley), and August, 1899 (Wainwright) ; bred at Barton on Humber in 
Lincs., May, 1907 (G. W. Mason); Guestling near Hastings in 1891 
(Bloomfield) ; and a Lyndhurst garden on 2nd June, 1902 (Adams). In 
my own limited experience it has always been beaten from young birch 
bushes in woods, in which situation it has occurred to me at Reydon near 
Southwold on 4th June, at Bentley in the middle of June, and somewhat 
freely on 26th September, 1907, at Tuddenham in Suffolk. 
27. segmentator, Holmer. 
Mesoleius segmentator, Holmgr. Sv. Ak. Handl. 1855, p. 165, ?; Brisch. Schr. 
Nat. Ges. Danz. 1878, p. 85; Thoms. O. E. xix. 2049, ¢ ?. M. solitarius, Holmer. 
Sv. Ak. Handl. 1876, p.14, 3 ¢. 
Head almost broader than thorax, with vertex broad and not con- 
stricted posteriorly; clypeus short, mandibles stout and _ apically 
constricted ; mouth, clypeus, cheeks and a small quadrate mark above 
either side of clypeus pale testaceous; ¢@ with face flavous, usually tri- 
lobed with black above. Antennae nearly as long as body, apically 
subattenuate and hardly pilose, basally flavidous beneath; of ¢ shorter, 
with flagellum black. Thorax elongate and not gibbous; mesonotum 
shining, not alutaceous, obsoletely punctate, usually with hamate humeral 
marks flavous; mesosternum centrally rosy or sometimes flavescent, 
laterally sparsely and strongly punctate ; metathorax narrow, with petiolar 
area nearly circular and not extending beyond apical third. Scutellum 
laterally stramineous, rarely immaculate. Abdomen longer than head and 
thorax with segments three to seven, apically whitish, of 2 gradually 
compressed, of ¢@ parallel-sided ; basal segment elongate and broad with 
discal sulcus central, somewhat deep and extending beyond spiracles ; 
second quadrate, very finely alutaceous, somewhat shining; third quad- 
rate; and venter, with terebra, stramineous. Legs somewhat stout, pale 
with the hind tarsi infuscate, a little shorter than their tibiae, spinulose 
beneath, and in 6 longer; claws somewhat stout. Wings hyaline, 
stigma black and emitting radius before its centre, areolet usually want- 
ing ; lower basal nervure postfurcal. Length, 6>—8 mm. 
The areolet is sometimes complete or subcomplete. Distinct in its 
mesesternal puncturation from JZ. sfernoxanthus, with which it agrees in 
its centrally broadly rounded clypeal apex with distinct lateral angles, 
somewhat distinct notauli and metathoracic areae, oblique nervellus, 
stoutish legs with calcaria not extending to centre of metatarsus, and 
partly pale Q face. 
This species occurs in France, Sweden,.and Prussia, where Brischke 
bred it from larvae of Wematus perspicillaris (Pleronus dimidiotus) and P. 
salicts, so it was very likely to be found with us. A single male with no 
locality (Trans. Ent. Soc. 1881, p. 163) is recorded by Bridgman, 
