422 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 57. 



Genus EPIRHYSSA Cresson. 



Epirhyssa Cresson, Proc. Ent. Soc. Phila., vol. 4, 1865, p. 39. Genotype. — 

 Epirhyssa spedosa Cresson.' 



According to various authors (Ashmead, Morley) the genus Rhys- 

 sonota Kriechbaumer is a synonym of Epirhyssa Cresson, but as this 

 group is not well represented in the collections of the United States 

 National Museum and as it is outside the area covered by this paper, 

 no discussion, other than to present a few notes on Cresson's types, 

 will be given at this time. The genus Epirhyssa has not been under- 

 stood by American authors and the following notes are presented in 

 order that Cresson's species may be placed in the present classi- 

 fication. None of the Nearctic species assigned to Epirhyssa belong 

 there. 



Generic characters. — Clypeus truncate; frons unarmed; nervulus 

 interstitial; areolet wanting; propodeum not areolated; first sternite 

 fused with the first tergitfe basally; spiracles of the first tergite at 

 about the basal third, the distance between them less than the dis- 

 tance from one of them to the anterior margin of the segment; 

 second sternite of the female with two median tubercles near base; 

 second tergite without lunulae; abdomen of the male a little more 

 than twice as long as the head and thorax, slightly widening |>os- 

 teriorly; tergites three to five rather shallowly emarginate in male, 

 hardly emargiuate in female. 



TABLE TO cresson's SPECIES. 



1. Stigma black; wings yellowish with the apical margin brown; scutum yellow except 



for the brownish notauli mexicana Cresson. 



Stigma yellow; wings subhyaline with the apical margin somewhat dusky; scutum 

 mostly brown 2. 



2. Tergites beyond the third uniformly castaneous; hiud legs castaneous; recurrent 



postfurcal by the length of the intercubitus spedosa Cresson. 



Tergites beyond the third yellowish with the basal margins brownish; hind legs 

 mostly yellow; re<'urrent postfurcal by half the length of the intercubitus. 



alternata Cresson. 

 RHYSSELLA, new genus. 



Genotype. — Rhyssa nitida Cresson. 



The species which are grouped together under the new generic name 

 Rhyssella have been placed both in Rhyssa and Megarhyssa. They 

 are in general habitus more like Rhyssa but in structural characters 

 are closer to Megarhyssa. The more recent classifications have 

 placed them in Megarhyssa but it seems to the writer that their 

 habitus, habits and structural characters are of sufficient value to be 

 considered generic. 



Generic characters. — Clypeus truncate; nervulus postfurcal; areolet 

 variable, normally present, but often petiolate or completely wanting; 



'Morley, Rev. Ichn. Brit. Mus., pt. 2, 1913, p. 4. 



