Polysphincia.] BRITISH ICHNEUMONS. 123 



3. tuberosa, Grav. 

 Polyaphincta tuberosa, Gr. I.E. iii. 115; Tasch. Zeits. Ges. Nat. 1863. p. 271 ; 

 Entom. 1882. p. 169 (fig.), ? ; Holmgr. Sv. Ak. Handl. 1860, n. 10. p. 31, <f ? ; 

 cf. Brisch. Schr. Nat. Ges. Danz. 1880. p. 114; et Thorns. O. E. xii. 1252. 



An elongate, cylindrical and somewhat shining black species. Head 

 strongly constricted behind the eyes ; clypeus piceous and palpi pale 

 stramineous. Antennae simple filifomi and a little shorter in 9 than the 

 body; infuscate and darker above. Thorax gibbulous, narrower than the 

 head and longer than high ; pronotum, and perhaps a callosity before the 

 radix, sometimes white ; mesopleurae smooth and notauli very distinct ; 

 metathorax with the areola elongate, parallel-sided and apically incom- 

 plete. Scutelkmi sometimes apically badious, with the postscutellum 

 concolorous. Abdomen cylindrical, double the length of the head and 

 thorax, and as broad as the latter ; basal segment nearly smooth with no 

 carinae, a little longer than the hind coxae and transversely impressed 

 before its apex ; segments two to five ver\- une\en and each with a shin.- 

 ing and determinate tubercle on either side ; terebra not quite half the 

 length of the abdomen, with the valvulae parallel-sided and pilose. Legs 

 somewhat slender ; the anterior red or fulvous with the coxae and tro- 

 chanters paler than the hind ones and usually more or less nigrescent ; 

 hind legs infuscate with the coxae and trochanters at least basallv black, 

 femora entirely or above nifescent, tibiae except apically and before the 

 base and often the two or three first tarsal joints basally whitish ; apical 

 tarsal joint dilated and double the length of the penultimate, claws of 9 

 distinctly lobate basally. ^^'ings normal, slightly clouded ; stigma and 

 radius infuscate or dull stramineous, radix and apex of the tegulae white ; 

 radial cell lanceolate ; nervellus distinct and intercepting only slightly 

 below the centre. Length, 5 — 8 mm. 



This species is among the largest of the genus and its legs are con- 

 siderably variable in colour. It may be known by the head, viewed from 

 in front, being broader than high and, behind the eyes, shining and con- 

 stricted ; the antennae obscurely infuscate beneath ; the very distinctly 

 tuberculate sides of the abdomen and its short terebra. The central 

 segments are said to be sometimes slightly red-margined. It resembles 

 Pimpla pictifrons, Thoms., but is larger with the areolet incomplete and 

 the flagellum more attenuate apically. 



Some interesting details of his rearing this species are given by Bignell 

 (Entom. 1882, p. 174) : he beat a spider, Epcira cuciirbitina, Clerck., from 

 an oak at Stonehou.se in Devonshire on 22nd of the preceding May 

 and across its back was lying a larva, the whole resembling " a miller's 

 man carrying a sack of flour." The larva was full-fed on the 24th. " It 

 had no legs, but in place of them it had .sucking-discs, two on the .second 

 segment and four on the third and fourth, six of them occupying the usual 

 place of the legs ; the other four were half covered with the skin-fold 

 u.sually seen on lepidopterous larvae ; on its back it had eight tubercles, 

 the first on the fourth, the others on the seven following segments ; each 

 tubercle was surmounted by two rings of booklets, with three or four in 

 the centre. The object of these was to su.spend itself by the web while 

 feeding on the la.st remains of its victim, and holding on after it was con- 

 sumed ; when the whole of the spider's body had been extracted, the legs 

 and empty skin were allowed to fall down. The larva then commenced 

 to make itself a cocoon, which was finished by the third day ; it was 



