ICHNEUMONTD^. 311 



the posterior coxfe and femora are always more or less blaek, and the abdomen 

 varies from entirely honey-yellow to ferruginous banded with black. Length 

 2J — 4J lines. I. pectoralis seems to be closely allied to this species, differing 

 principally in the colors of the posterior legs. Say must have meant that the 

 l)leura has a large yellow spot between the anterior and intermediate legs, in- 

 stead of the "intermediate and posterior" jaair, the four posterior coxpe being 

 nearly or quite contiguous. 



I. faeetus. — y. Head whitish, vertex and back of occiput black; antennae 

 long, slenilcr, blackish above, with a broad white or yellowish annulus beyond 

 the middle, the basal half beneath whitish ; pectus and pleura white or whitish ; 

 prothorax more or less white, sometimes honey-yellow and black, margined 

 with white; mesothorax varies from entirely honey-yellow to entirely black, 

 sometimes there are two faint, pale, longitudinal lines in the middle, and some- 

 times two short white lines or a square white spot on the disk; tegulse, scu- 

 tellurn and post-scutellum white or yellowish-white ; metathorax whitish, vari- 

 ed with honey-yellow at base, sometimes entirely honey-yellow; wings hyaline, 

 iridescent; legs pale honey yellow, the four anterior coxse and trochanters and 

 posterior pair beneath white, tarsi pale yellowish ; abdomen narrow, shining, 

 entirely honey-yellow; first segment slender, smooth and jjolished, the extreme 

 tip sometimes pale yellow. Length 4 — 4i lines. 



JIab. West Virginia, (Eidings.) Fifteen % specimens. 



I. utilis-— '^. Pale honey-yellow; head broad, short, black or brown; face,ely- 

 peus, mandibles and palpi yellow; antennae long, filiform, honey-yellow, dusky 

 above, basal joint yellow beneath; suturesof the thorax blackish; tegulse, sutural 

 line before the wings and a short line beneath, anterior margin of prothorax, 

 scutellum and the post-scutellum. yellow; metathorax sometimes tinged with 

 yellow behind; wings subhyaline, nervures and stigma honey-yellow, areolet 

 subtriangular ; legs honey -yellow, the four anterior coxre and trochanters pale 

 yellow : abdomen entirely pale honey-yellow, first segment slender, slightly 

 riwollen at tip which is clearly and finely punctured and shining. Length 4 

 lines. 



Hab. — Mass., (Ridings); Conn., (Norton). — This is a parasite on the Canker- 

 worm, and is closely allied to faeetus. 



I. tumidifrons. — J. Small, stout; head black, face protuberant (but not so 

 much as in Exochus), ferruginous, clypeus and mandibles also ferruginous ; an- 

 tennse short, stout, convolute, joints short and thick, basal joint large, subglo- 

 bose, basal third ferruginous, middle yellowish-white and apical third black, 

 thorax ferruginous, pleura beneath, the spaces on each side of scutellum, and 

 the metathorax entirely, black; scutellum pale yellow, the post-scutellum 

 tinged with ferruginous; metathorax punctured, shining, central area large, 

 elongate-subquadrato, not well defined; teguliB honey-yellow; wings subhya- 

 line, iridescent, nervures pale brown, stigma honey-yellow, areolet broad, 5-an- 

 gular; legs robust, ferruginous, including their coxse; most of the posterior fe- 

 mora and tips of their tibiae, biacK; abaomen Droad, depressed, pale ferrugi- 

 nous, apex of fourth segment and the remaining segments black; apical seg- 

 ment with a central yellow spot. Length 2} lines. 



Hab.—l\Vn\o\s, (Dr. Lewis.) One J specimen. The protuberant face resem- 

 bles that of the genus JExochus, but the antennce are convolute and the areolet 

 of the anterior wing is 5-angular and complete. In some specimens of this spe- 

 cies the color of the thorax may vary from entirely ferruginous to entirely 

 black, as with annulvpes. 



