SEEPHOID AND CHALCIDOID PARASITES OF THE HESSIAN FLY 101 



or very slightly broader than long; club solid, distinctly broader than the last 

 funicle joint, as long as the three preceding joints combined, ovate, and termi- 

 nating in a slender process which is approximately one fifth as long as the rest 

 of the club. Thorax one and one half times as long as broad, nearly elliptical 

 in dorsal outline; pronotum short, a little narrower than mesoscutum, mostly 

 declivous or nearly perpendicular, the dorsal aspect consisting of a very narrow 

 transverse and smooth line which is bounded anteriorly by a delicate carina ; 

 mesoscutum nearly twice as broad as long, strongly punctate, the punctures 

 deeper than in most of the other species ; parapsidal grooves weakly impressed 

 anteriorly, entirely effaced on the dorsum ; scutellum a little shorter than the 

 mesoscutum and with similar sculpture, about as broad as long; axillae 

 broadly separated, very weakly sculptured and more or less shining ; propodeum 

 approximately two thirds as long as scutellum, with a very short rounded 

 neck at apical middle, without carinae, the lateral folds absent except for a 

 small rounded fovea on each side at basal margin, spiracular sulci weakly 

 impressed posteriorly, spiracles oval, the whole surface of propodeum weakly 

 reticulated and somewhat shining; pleura mostly shining but with a depressed 

 area in middle of each mesopleuron punctate and dull; pronotum posteriorly, 

 mesoscutum and scutellum sparsely clothed with conspicuous silvery hairs, the 

 propodeum laterally with longer and more numerous hairs. Legs slender, the 

 hind coxae weakly reticulated. Fore wings extending to apex of abdomen, twice 

 as long as broad, bare behind the submarginal vein, the discal cilia weak and 

 marginal cilia short; submarginal veins about twice as long as marginal, 

 postmarginal and marginal veins about equal, stigmal vein about half as long 

 as marginal. Abdomen smooth, about as long as head and thorax and about 

 as broad as thorax, long ovate, pointed at apex; first tergite comprising about 

 one fourth of the total length of abdomen ; ovipositor, except its extreme apex, 

 concealed from above. 



Head and thorax deep black, abdomen yellowish testaceous above and be- 

 neath, with the lateral margins from base to apex of fourth or fifth tergites 

 narrowly blackish ; antennal scape blackish or dark brown, often paler at base ; 

 pedicel also blackish or brownish; flagellum usually entirely dark testaceous 

 or honey yellow ; mandibles reddish ; coxae black, the posterior pair often more 

 or less yellowish on the inner side; rest of the legs honey yellow, the femora 

 usually darker than their tibiae; wings hyaline, the venation testaceous; ovi- 

 positor sheath black. 



Male. — Length 1.2 to 2.4 mm. Antenna not or very slightly clavate, 13- 

 jointed, the flagellar joints covered with hairs that are nearly equal in length 

 to the segments ; pedicel as long as broad ; ring joints small ; first funicle joint 

 a little longer than the pedicel and also a little longer than any of the other 

 funicle joints; second and following funicle joints subequal in length, each set 

 off from the preceding joint by a short but distinct pedicel, and each usually a 

 little longer than broad but in some specimens subquadrate. Abdomen elliptical 

 with a very short petiole, narrower than the thorax, and usually a little longer 

 than the thorax. Whole antennae black or very dark brown ; legs also blackish 

 or fuscous with the knees, apices of tibiae, and the tarsi usually testaceous; 

 abdomen variable in color but usually dark brown or blackish at base and apex 

 as well as laterally, with a large yellowish spot medially above and below. 

 Otherwise like the female. 



The female holotype of mordellistenae agrees with the foregoing 

 description, but the male associated with this holotype female by 

 Crawford does not agree with the males here described and is be- 

 lieved to be a different species. This male differs from the female in 

 some ways that cannot be reconciled as sexual differences. The dorsal 

 aspect of the pronotum is as wide as the mesonotum and in nearly the 

 same horizontal plane as the mesoscutum. It is also distinctly 

 punctate and lacks the delicate carina at the edge of the declivity. 

 The marginal vein of the fore wing is distinctly a little longer than 

 the postmarginal vein. The vertex of the head is strongly punctate 

 instead of nearly smooth, and the propodeum and pleura are much 

 more strongly sculptured than in the female. The scape extends well 

 above the front ocellus, The female is deep black, while this male 



