Pen/hoiis.] BRITISH ICHNEUMONS. 49 



Besides preying upon Cemonus, Ptinphredon and Trypoxylon, this species 

 was thought by Fitch (Entom. 1880, p. 258) to have devoured the larvae 

 of Cvnips Kollari, though the parasite was not conclusively determined 

 {cf. also Ratz. Ichn. d. Forst. ii. 108). It is very rarely seen on the wing 

 or at large at all, though the specimens taken by Bridgman at Norwich, 

 Tuck at Chippenham Fen in Cambs., Capron at Shere in Surrey, and 

 Bloomfield at Guestling in Sussex were so caught. The more usual way 

 of securing it is by gathering bramble sticks during the winter; by this 

 method Parfitt has bred it in Devon, Martineau along with Pemphndon 

 lethifcr and I'Jlompus aurattis at ]\Iarston Green, near Birmingham ( at 

 .Meeting, Birm. Ent. Soc. 20th Feb., 1905), Giraud from Cernonus unicolnr 

 and Ptrnphndoii lui^ithris (Ann. Soc. France, 1877, p. +10); and Mr. Bowd- 

 ler has sent me bramble stems from Blackpool, together with Pemphredon 

 lethifer, Perithous divinator and Elampus atiraiiis, bred from them. He 

 tells me that in 1904 he bred forty Ptinpredon, three male and seven female 

 Perithous and se\en Elampus, though wliether the Pimplid was a primary 

 or secondarv parasite was not ascertained. That it is at least sometimes 

 hvperparasitic upon the Chrysid was discovered by Kriechbaumer ( Ent. 

 Xachr. xxxvii, p. 480), who says that on 23rd March he took a fully 

 coloured nvmphofthe Perithous owl oi 3. cocoon oi E. auratus, and this 

 completed its ecdvsis on 27th June following: "hence it follows that the 

 host-larva was onlv attacked when it was nearly or quite full grown, since 

 I actuallv found two \\eeks ago the larvae as ektoparasites on full-grown 

 Chevrieria unicolor ( Punphndou ShuckardiJ lar\ae. The females of 

 PJphialtes divinator therefore bore from outside, through the wood of the 

 Rubus twigs, into the more or less grown larvae of their host; and the 

 voung Ephialtcs larvae suck as ektoparasites on the back of the host. As 

 K. divinator makes no cocoon, one only finds the lar\'ae in one when the 

 host-larva constructs it." He also instances Odynerus ( Hoplopus) laevipcs 

 as an alternative host. Frisby bred five females and two males in 1907, 

 from bramble stems, gathered during that spring at Redhill Common, 

 together with Pemphredon lethifer. Adams has caught the female at 

 Lvndhurst in the New Forest. 



C. Verhoeff, of Bonn am Rhein, in his " Contributions to the Biology 

 of the Hymenoptera" (Zool. Jahr. 1892, p. 741 et seqtj.) gives an interest- 

 ing account of the economy of this species, which he found much com- 

 moner in Rubus stems than P. mediator, with which indeed he appears to 

 have at first confused it. He says that proterandrie always obtains in 

 this species and gives a table showing that of eight specimens of the 

 spring brood raised from Psen at rat us all the males emerged first, one as 

 early as the 7th March, though in the autumn brood one female emerged 

 from Chevrieria unieolor on the last dav of July and the final male not till 

 August 6th, when the remainder of the females began to appear. They 

 hibernate as fullv grown larvae and are ektoparasitic, spinning no cocoon. 

 For an account of their oviposition, one is referred to the Berl. Ent. Zeit. 

 1892, no. iv, " On the Biology of fA/r«(;7/j/)<//7t7«w/," which I have not 

 seen. The most usual host of this species with him is Chevrieria unieolor, 

 but he proved it also to prev upon Stigmus pendulus fSolskyi) and Psen 

 alratus. For its parasitism upon Hoplopus (Odynerus) laevipes, ef. Biol. 

 Aphor. p. 17. He asserts that the parasite has lived for countless gener- 

 ations with Ruhus inhabiters, which are normally double brooded and 

 that its larvae of the spring brood have inherited the habit of becoming 

 imagines the following August ; from these, which are abroad at about 



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