86 BRITISH ICHNEUMONS. [ Bassus 

white. Apex of basal segment conspicuously white. Legs red with the 
anterior coxae partly but not the hind ones, the hind tarsi and whole of 
the remainder of their tibiae, black. Abdomen not red-marked. Length, 
74 mm. 
Instantly known from all the preceding by its conspicuously white apex 
of the basal segment, larger size and much stouter conformation ; and 
distinguished by the basally black anterior but immaculate red hind coxae, 
stouter and more deeply impressed abdomen. 
This handsome species is by no means common with us and I have but 
twice met with it personally; in July, 1903, it was sucking the stylopods 
of Heracleum sphondylium on the cliffs at Southwold in Suftolk ; and at the 
end of the same month, 1904, I captured another flying along among 
marram grass on the sea-shore at Kessingland, some five miles further 
north. I have examples taken by Peacock at Cadney in Lincs. and by 
Col. Yerbury at Nairn in Scotland in the middle of July, 1904; Bignell 
has recorded it from Bickleigh and the Walkham Valley, in Devon, on 
the 3rd of June and of August; Haliday, in his Dublin Museum MS., 
says it was found commonly by him in Ireland; and Rev. ‘T. A. Marshall 
tells us (Entom. 1872-3, p. 432) that Francis Walker captured it in the Isle 
of Man, and he himself took it at Botusfleming in Cornwall. On the 
Continent it was for long intermingled with 2. ¢ricinctus ; Holmgren in 
Sweden and Brischke in Prussia have bred it from a Syrphus pupa, and 
Bouché once raised it (Naturg. 147) from a puparium of Syrphus bal- 
teatus, as quoted by Ratzeburg (/.c.), Curtis (Farm. Ins. 82), Kirchner and 
Gaulle. 
5 variicoxa, Thoms. 
Bassus albosignatus, var. 1, Gr. I. E. iii. 344, ¢ (?); var. 3, Holmgr. Sv. Ak. 
Handl. 1855, p. 354. B. varicoxa, Thoms. O. E. xiv. 1460; Morl. Trans. Ent. 
S0G..1905)p; 420, 12) 
A black species with the mouth, clypeus, facial orbits, epistoma, marks 
before the concolorous tegulae, more or less of scutellum, and the hind 
tibial band, white. Legs red with the anterior coxae basally and hind 
ones entirely, hind tarsi and whole of the remainder of their tibiae, black. 
Abdomen rarely obsoletely red-marked. Length, 4—54 mm. 
This is another female closely allied to 2. ¢ricinctus, from which it 
differs in its partly black anterior coxae and entirely concolorous hind 
ones; and from &. annulatus in its white-marked epistoma and lack of 
all rufescent colouration at the apex of its hind tibiae, the more deeply 
impressed incisures, and the larger humeral and scutellar pale markings. 
It is distinguishable from 2. albosignatus by its shorter hind tarsi and 
claws, more finely punctate metathorax, frons and pleurae, and hardly 
traceable areola. 
It is of fairly frequent occurrence with us and appears to be gregarious, 
since 1 have very rarely taken it singly. Mousehold, near Norwich 
(Bridg. Trans. Norf. Soc. v. 628); Braidburn, near Edinburgh in 
July, 1899 (Evans); I have it from Point of Aire (Tomlin); Brisling- 
ton, near Bristol (Charbonnier) ; St. Kilda (Waterston) ; and Felden in 
Herts (Piffard). In Suffolk, Tuck has found it at Finborough Park and 
Tostock; and I have taken it occasionally by sweeping on flowers of 
Angelica, Heracleum, etc., from June 1st to August 30th at Tuddenham 
Fen, Raydon Wood, Dunwich, Reydon marshes, Claydon bridge, and in 
