ICHNEUMON FLIES— ASHMEAD. 141 



Tribe I. EXOTHECINI. 



1862. Exothecoidse, Family, FoKSTER,Verh.d. naturh. Vcr. jir. lUiciiil., XTX, {).27i». 



1885. Exoiheddes Marshall, Trans. Ent. Soc. Lond., p. i). 



1887. Exothecina', Subfamily, Creshon, Syn. Hym. North America, p. 56. 



1888. Exotheddie, Tribe II, Marshall, Species des Hym. des Braconides, I, p. 65. 

 1900. Exothecini, Tribe V, Ashmead, Smith's Insects of New Jersey, p. 597. 



This tribe i.s readil}^ separated from the others b}^ th(^, iinmargined 

 occiput. It comes nearest in this respect to the sii])faniily liraccmind'^ 

 with which tlie species are easily confused. The venation of the hind 

 wings is, however, quite distinct from the species in that group, the 

 su})median cell being always much longer, nearly half the length of 

 the median cell, while in the Bniconinm it is never more than one- 

 third the length of the median cell. 



Eight genera belong to this tribe, separable as follows: 



tahle of genera. 



Suturiform articulation distinct, crenulate 2 



Siituriform articulation obsolete 3 



2. Stigma large, oval, the marginal cell closed a little before the tip of the wing. 



(1075) ZmnefJaspiluH Ashmead, new genus. 



(Type, Zamegaspilus Hopkinsi Ashmead, manuscript.) 



Stigma normal, the marginal cell closed at the apex of the wing; metathorax 



with a delicate median carina; second dorsal abdominal segment with a 



cross furrow ( 1076) PJtanomeris Forster. 



.S. Radius originating from the middle of the stigma 4 



Radius originating far beyond the middle of the stigma 5 



Radius originating much before the middle of the stigma. 



Submedian cell much longer than the median, the transverse median nerv- 

 ure joining the median vein far beyond the origin of the basal nervure. 



( 1077 ) Exothecas ' Wesmael. 



Submedian cell not longer than the median, the transverse median nervure 



interstitial with the basal nervure ( 1078) Xynoh'ms Forster. 



4. Recurrent nervure received by the first cubital cell. Second abscissa of the 



radius more than twice as long as the first; abdominal segments 2-3, 

 smooth, shining, the first sometimes aciculate. 



Second discoidal cell closed ( 1079) lihyi^lpolix Forster. 



Second discoidal cell open ( 1080 ) Lytopylus Forster. 



Recurrent nervure received l)y the second culjital i-ell. 



(1081 ) Jlalliydoimis Forster. 



5. Recurrent nervure received by the first cubital cell; second abdominal segment 



iritliout a transverse furrow ( 1082) Xenarcha Forster. 



Tribe II. RHYSSALINI. 



1862. Jihyssaloidiv, Family 7, Forster, \'erh. d. naturh. Ver. j)r. Rheinl., XIX, 



pp. 228 and 241. 

 1885. Rhyssalldes Marshall, Trans. Ent. Soc. Lond., p. 9. 

 1887. Rhys-mlhiH, Subfamily, Cresson, Syn. Hym. North America, p. 56. 

 1900. Rhysnalini, Tribe IV, Ashmead, Smith's Insects of New Jersey, p. 596. 



This tribe is composed of a number of minute species easily confused 

 with some in the tribe Exothecini, and trreat care must be given to the 



