DUBLIN UNIVEKSITY ZOOLOGICAL AND BOTANICAL ASSOCIATION. 167 



I propose at the same time, with your permission, to characterize 

 this very distinct and hitherto undescribed form in the family by the 

 generic and trivial name under which I have formerly communicated 

 specimens to some of my entomological correspondents in these countries 

 and abroad. 



The family Diapridae is undoubtedly closely allied to the Proctotru- 

 pidae {Proctotrupes, Monomachus, Pelecinus), of which, indeed, the older 

 authors considered it as forming part. If it is thought better not to 

 multiply families, the two may still be kept united under the latter 

 name, provided that the nature and distinctions of the two subordinate 

 groups, they will in that case constitute, be kept in view not the less. 

 For our immediate object, it will be enough to mention the difference 

 in the form of the metathorax, which in the genuine Proctotrupidae is 

 prolonged beyond the insertion of the hind coxae in an attenuated pro- 

 cess, while in the Diapridae it terminates rather abruptly behind the 

 sockets of these. The singular structure also of the Ovipositor (the 

 Spicula seemingly coalescing with the Calamus), which I detected in 

 Proctotrupes, and have described elsewhere (" Hymenoptera Britannica 

 Oxyura," p. 7 ; H. Bailliere : London, 1839), has not occurred among 

 the Diapridae, the composition of it being as usual, even in the remark- 

 able insect which forms the more especial subject of the present Note. To 

 the description of this I prefix a slight summary of the chief indigenous 

 groups of the family, for the sake of exhibiting the essential characters 

 of this genus more distinctly by comparison. At some future time I 

 may perhaps be permitted to lay before this Association some other 

 illustrations of the native species, at greater length than I can venture to 

 encroach on your attention at present. 



Of this family, Diapridae, in the British Fauna, five principal groups 

 have been established, — Helorus, Ismarus, Belita, Diapria, Platymis- 

 chus, — most of them requiring some further subdivision, especially the 

 fourth, the more numerous species of which have already afforded seve- 

 ral dismemberments, which may hereafter prove actually entitled to 

 generic rank, — Paramesius, Spilomicrus, Basalys, Aneurrhynchus, "West- 

 wood, and Galesus n. To those first five, which I have recognised as 

 established genera, it is proposed here to add another, co-ordinate in 

 character, though limited as yet, in its contents, to one known species. 



Fam. DiAPKiD^;. 



Tibiae anticae calcari unico, posteriores binis. Antennae articulis 12, 

 superque. Mandibulae dentatae. Metathorax coxarum posticarum 

 insertionem parum superans. Abdomen segmento primo petiolum fin- 

 gente, secundo amplissimo. 



Very little is known of the early states of the insects of this family; 

 the few whose history has been traced are mostly parasites in the larvae 

 of Coleoptera and Diptera. Hot a single species is to be found described 

 in any of the works of Linnaeus, who would doubtless have ranked them 

 among his Ichneumones minuti. 



