198 BRITISH ICHNEUMONS. | Acrolomus 

6. succinctus, Grav. 
Tryphon succinctus, Gr. I. E. ii. 166, 3; cf.i.688; Ratz. Ichn. d. Forst. i. 128; 
ii. 116; Fonsc. Ann. Soc. Fr. 1849, p.220, ¢. TJ. marginellus, Gr. I. E. ii. 167; 
Fonsc. Ann. Soc. Fr. 1849, p. 220; Ratz. Ichn. d. Forst. iii. 124, 9. Exenterus 
succinctus, Holmgr. Sv. Ak. Handl. 1855, p.230, ¢. Cfeniscus succinctus, 
Brisch. Schr. Nat. Ges. Danz. 1878, p, 104, ¢ ?; cf. Hal. Ann. Nat. Hist. 1839, 
p.113 et Thoms. O. E. ix. 891. Acrotomus succinctus, Pfank. Zeits. Hym. Dip. 
1906, p. 94. 
A very finely punctate and very shining species, with the abdomen not 
red-marked. Head transverse, sparsely punctate and posteriorly nar- 
rowed ; mouth, clypeus, cheeks and face, stramineous; clypeus slightly 
depressed before its rounded apex ; face a little elevated and pubescent, 
with a black tubercle below the scrobes. Antennae somewhat shorter 
than body, filiform and nigrescent, becoming apically ferrugineous 
beneath. Thorax narrower than head, pubescent, sparsely punctate and 
black with margin of pronotum and small callosities before and below 
radices stramineous ; notauli distinct, pleurae centrally smooth ; meta- 
thoracic areae distinct, with areola pentagonal. Scutellar and post- 
scutellar apices stramineous, the former foveolate. Abdomen subfusiform 
and strongly nitidulous, black with apical margin of all the segments and 
whole venter stramineous; basal segment gradually dilated apically, 
laterally margined, with discal carinae extending beyond centre and the 
apex rectangular; terebra stout, black and not exserted. Legs slender, 
red; anterior coxae and trochanters stramineous, hind ones of ¢ sub- 
concolorous; hind tarsi and tibiae nigrescent with base of latter often 
pale ; tarsal claws pectinate. Wings slightly clouded; stigma infuscate, 
tegulae stramineous. Length, 6 mm. 
It is similar to A. sevczncfus, but more slender and shining with different 
colour. I at first thought there could be but little doubt that Brischke 
was correct in his supposition (/oc. czt.) that 7. 5-cénctus, Grav., is the 
male of 7. succinctus, though Thomson did not follow him, and he him- 
self continued to use the later name up to 1892, since which time no one 
has mentioned this species till Pfankuch disproved it by examining the 
types in 1906. 
One of the commonest of the present group both here and in north- 
west Europe where it is found on umbelliferae in July, extending to Sep- 
tember. Ratzeburg bred it in Germany from Lophyrus virens and Athalia 
spinarum, Fab. = Colibri, Christ ; and Gaulle adds Pres/¢phora geniculata, 
in his French Catalogue. It appears to have been unknown to Stephens, 
but Marshall found it at Botusfleming in Cornwall, and Bignell at Bick- 
leigh in Devon in the middle of August. I have seen examples taken at 
Lynn in Norfolk (Atmore), Felden (Piffard), Abinger Hammer in Surrey, 
August, 1900 (Butler), Lydford in October, 1895 (Garde), New Forest 
(Miss Chawner), Taunton in August (Charbonnier), Greenings in June, 
1871 (W. Saunders), Shere (Capron), Aldeburgh in the middle of Sep- 
tember, 1899 (Tuck), and have myself found it at Lyndhurst in the middle 
of July. 
