248 PROCEEDINGS OF THE NATIONAL MUSEUM vol.84 



Systematic relationshijys. — The affinities of Exetastes and its closest 

 allies are, in my opinion, on the one hand with the Lissonotini, 

 especially \\4th such genera as Arenetra Holmgren, Alloplasta Foerster, 

 Echthrodoca Schmiedekiiecht, Cryptopimpla Taschenberg, and Lam- 

 pronota Curtis, and on the other hand with Banchus Fabricius and 

 its allies. 



Of all the characters listed in the above description onl}^ one will, 

 by itself, distinguish Exetastes from all the genera known to me that 

 are at present assigned to the Lissonotini. Tliis is the fracture of 

 the nervellus far above the middle. Even the other most strildng 

 characteristic of the genus, that of habitus, is approached rather 

 closely by Cryptopimpla, Echthrodoca, and Arenetra. and even more 

 closely by certain tropical genera such as Stictolissonota Cameron. 



The relationship of Exetastes and its allies to the typical Banchini 

 is distinctly more remote, although the only known characters 

 exhibited by all true Bancliini that are not duplicated in the Exetastes 

 group are the broad upper tooth of the mandible and the form of the 

 apex of the abdomen in the female. 



The correct position of these two groups of genera has long been 

 a matter of disagreement. Most writers have followed the tra- 

 ditional placing in the subfamily Ophioninae and have treated them 

 as belonging to a single tribe, the Banchini. More recently some 

 writers have transferred the tribe Banchini to the subfamily (Pim- 

 plinae) Ichneumoninae, some being inclined to divide the tribe into 

 the Banchini and Exetastini. In my opmion the tribe Exetastini is 

 not sufficiently distinct to justify its separation from the Lissonotini 

 (vidth which Seyrig has correctly combined the Glyptini). The genera 

 comprised in this group are Exetastes Gravenhorst, Allexetastes 

 Kokujev, Tetractenion Seyrig, Tegona Morley, Agathilla Westwood 

 {=Agathohanchus Ashmead), and Rhynchexetastes Cameron. 



Banchus and its allies, A^awoia lAshmead (probably synonymous 

 with Banchus), Rhynchobanchus Kriechbaumer, Ceratogastra Ash- 

 mead, Banchoides Dalla Torre, and the apparently synonymous 

 Eponites Cameron, I consider to form a sufficiently homogeneous and 

 distinct group to maintain as the tribe Banchini. 



Of the other genera assigned to the Bancliini by more recent writers 

 Leptobatopsis Ashmead has been referred by me to the Lissonotini, 

 where Fintona Cameron also evidently belongs; Baliena Cameron has 

 been synonymized by Morley with Pseudeugalta Ashmead; Xenoschesis 

 Foerster belongs to the mesoleptine subtribe Notopygina; Aethria 

 Tosqinet appears from the description to be synonymous with Eugalta 

 Cameron; Lapton Nees and Allotheca Cameron are unknown to me, 

 and Ithagenes Foerster as j^et contains no species. 



