No.ViOii. ICHNEVMON FLIES— ASH3fEAJ). 25 



,Mct;itliMrax usually ]if(i(liicc(l licvdiid (he iiisci-tion <il' liiml cdx.T, llic ipciiolar 

 area and tlit' atvola usually confluent and extendinir clcai- In llu' 

 base; ovipositor very short, at the most subexserted. 



Trilx- 1. Si'ii.i'NiM. 

 Metathorax not priKlucnl beyond the hind eoxa>; ovipositor exserteil. 



Front wings with a complete areolet; head usually ((uadrate; anti^nna' and 



legs most frequently stout Tribe 1 1 . ]'TrY<iAi)KroNiNi. 



Front wings with the ari'olet incomplete, open behind lii \\antin<^^ liead not 

 or rarely quadrate; antennte and legs usually siendi'r. 



Basal nervure not strongly curved inwardly Tribe III. 11 km item xr. 



Basal nervure strongly curved inwardly Tribe IV. pKzoMAt iiixr. 



2. Wings fully developed .'> 



Wings absent or abbreviated Tribe TV. Pezomachini. 



Metanotum not areolated Tribe TV. Pezomachini. 



'A. Front wings with the stigma narrowed, the areolet variable, i)entagonal, or 

 small (juadrate, sometimes almost punctiform, more rarely open 

 l)ehind or entirely absent; discoidal cell with the lower apical angle 

 straight or obtuse, the basal nervure not strongly curved inwardly; 



abscissa of costa long 4 



Front wings with the stigma broad, triangular, the areolet ))entagonal in jtosi- 

 tion but open behind, the basal nervure strongly (curved inwardly; 



abscissa short. (Male. ) Tribe IV. Pezomaciiixi. 



4. Areolet entirely wanting Tril)e V. IIemigasterini. 



Areolet distinct, usually large, never very small, and always pentagonal, the 



sides convergent above or parallel Tribe VI. CmPTiNi. 



Areolet small, quadrate, sometimes almost jiunctiform, sometimes open behind, 

 but never pentagonal in i)osition Tribe VII. Mesostenini. 



Tribe I. STILPNINI. 



186S. StiIpnoi<Lr, Fannly 2S, FiiusTER, Verb. d. naturh. ^'er. ])j-. Rheinl., XXV, 



])}). 144 and 188. 

 1873. Stilpnina, Tribes, TnoMsox, Opus Ent., V, p. 468. 

 1884. Stilpnina, Tribes, Thomson, Opus Ent.,X, p. 1018. 

 1894. Sillpnl7ii, Tribe I, Ashmead, Proc. P^nt. Soc. Wash., Ill, p. 278. 

 1900. Stilpnini, Tribe I, Ashmead, Smith's Insects of New Jersey, p. 5(i8. 



This group is of small (^xtoiit and at one time, on act'oiuit of the 

 brevity of the ovipositor, was confu.scd and classified with the o-cnuine 

 Ichneumonines; but from these it is at once separated ])y the long-itu- 

 ninal furrow which separates the mesosternum from the nu^sopleura. 



The tribe is distinguished from the others in this subfamily not only 

 by the non-exserted, or at most, subexserted ovipositor, ))ut also by its 

 metathoracic characters. All, except two or three of the genera, have 

 I he metathorax long, gradually sloping from base to apex, and pro- 

 duced posteriorly beyond the insertion of the hind coxa3, with the 

 areola and the petiolar area contiuent, extending to, or almost to, its 

 base. 



Most of the species, too, are highly polished and have the abdomen 

 long, more or less compressed, rarel}^ short or broad, while the areo- 

 let in the front wings, although sometimes closed and pentagonal, is 

 most frequently wanting or open. 



