MONOGRAPH OF THE NORTH AMERICAN PROCTOTRYPID.^. 249 



3. Wiugs ■without basal and median veins.. 4 



"Wiugs with basal and median A'eins. 



Mesonotum with 2 iaint furrows. 



Antenn.'u subclavato moniliform, first fuuiclar joint very minute, 

 second somewhat larger, the following to 10th larger, gradu- 

 ally thickened, the last larger, conical Metaclisis Fiirster. 



Antennae submoniliform, first funiclar Joint very minute, second 

 larger, thickened, curved, the third small, triangular, the fol- 

 lowing except the last transverse moniliform, the last conical. 



MoNOCRiT.v Forster. 



4. Lateral ocelli nearer the apical ocellus than to the margin of eye. 



Mesonotum without furrows Isostasiu.s, Forster. 



Lateral ocelli nearer the margin of eye than to the apical ocellus. 



Mesonotum with faint furrows; antennae moniliform, pubescent, the first 

 two funiclar joints nearly equal, the second somewhat curved, 

 the third small, triangular, the four following moniliform, 

 the last conical Inostkmma Hal. 



Mesonotum with 2 distinct furrows; antennic filiform, pubescent, the 

 second funiclar joint long, cylindrical, longer than the first, 

 the third shorter than the first, the following oval, the last 

 about thrice as long as thick Acerota Forster. 



IPHETRACHELUS Haliday. 



Ent.Mag., iir, p. 273 (1836); Forster Hym. Stud., ii, p. 106 (1856). 



(Type, I. Jar Hal.). 



Head transverse, the froiis subcoiivex, smooth ; ocelli 3 in a triangle, 

 the lateral close to the margin of the eye; eyes rounded. 



Antennae inserted just above the clypeus, in 9 10-jointed, very long, 

 the terminal joints forming a club ; scape long, subclavate, funiclar joints 

 small, moniliform; in $ 9-jointed, the flagellar joints nodose-pedicellate, 

 with whorls of sparse long hairs. 



Maxillary i^alpi short, 2-jointed; labial palpi 1-jointed. 



Mandibles bifid at tips. 



Thorax oval, the prothorax slightly visible from above; mesonotum 

 with or without furrows ; scutellum gibbous, nearly round ; metathorax 

 short, rounded behind. 



Front wings ciliated, the submarginal vein ending in a knob a little 

 before the middle of the Aving. 



Abdomen long ovate, subsessile, subconvex, and narrower than the 

 thorax, the second segment very lai^ge, occupying most of the surface, 

 the following segments all short. 



Legs slender, the femora subclavate, the tarsi 4-jointed, the basal 

 joint of hind tarsi about as long as all the others together. 



The 4-jointed tarsi, and the 9-jointed, nodose-pedicellate antennae of 

 the male readily distinguish the genus. 



