106 MISC. PUBLICATION" 17 4, U.S. DEPT. OF AGRICULTURE 



other parasites of the hessian fly. In the antennae, propodeum, and 

 general appearance it resembles Meri&us destructor, but it may be 

 distinguished at once by the spot on the wing. 



Female. — Length 2 to 3 mm. Head transverse, distinctly a little broader 

 than the thorax, viewed from above nearly four times as broad as thick at 

 the middle, convex in front, broadly but not deeply concave behind, the tem- 

 ples narrow, not over one fourth as broad as the width of eyes; ocelli in an 

 obtuse triangle, the postocellar line distinctly longer than the ocellocular, the 

 latter equal to about twice the diameter of an ocellus; head viewed from in 

 front broader than high, about in the proportion of 38 to 30 ; malar space equal 

 to about one third the eye height; mandibles both 3-toothed; clypeal margin 

 straight or nearly so ; eyes ovate and bare ; antennal groove very shallow and 

 small ; whole head with strong reticulate-punctate sculpture, the clypeal area 

 convergently striated; labial palpi 3-jointed, maxillary palpi 4-jointed. An- 

 tennae inserted very slightly below the middle of face, very weakly clavate, and 

 clothed with short hairs ; scape cylindrical, slightly curved, and approximately 

 equal in length to the five following joints; pedicel 1% to 2 times as long as 

 broad, two ring joints transverse but very distinct ; funicle 6-jointed, the first 

 funicle joint a little longer than broad, the following joints subquadrate; club 

 a little shorter than the three preceding joints together, acuminate at apex, 

 and nearly solid but with the two transverse grooves usually indicated. Thorax 

 a little more than one and one half times as long as broad, about as broad 

 posteriorly as anteriorly ; pronotum as broad as mesonotum, strongly reticulate- 

 punctate; mesoscutum moderately strongly convex, sculptured like pronotum, 

 much broader than long, the parapsidal grooves weakly impressed anteriorly 

 but absent posteriorly ; scutellum convex, strongly sculptured like mesoscutum, 

 shorter than mesoscutum, the punctation at apex finer than on the disk ; axillae 

 separated by base of scutellum, sculptured like scutellum ; propodeum broad, 

 without a neck and without carinae, the lateral folds and spiracular grooves 

 also absent, the lateral folds usually represented by a fovea on each side of 

 the middle, whole surface of propodeum evenly reticulate-punctate; spiracles 

 small, elliptical. Legs rather stout ; hind tibia with one spur ; hind tarsi a 

 little shorter than their tibiae, the hind basitarsus not long. Wings fully devel- 

 oped, extending a little beyond apex of abdomen, bare at base for the whole 

 length of the submarginal vein, the marginal cilia short ; marginal vein thick- 

 ened, 4 to 5 times as long as broad, thickest at base ; stigmal vein usually about 

 three fourths as long as the marginal vein, but frequently very nearly equal to 

 it, the stigmal knob moderately large, rounded at apex, with a distinct stylet ; 

 postmarginal vein thin and about one and one half times the length of mar- 

 ginal vein. Abdomen approximately the same length as thorax and as broad 

 as thorax or a little broader, ovate, acute or subacute at apex, rather thick 

 dorsoventrally, nearly smooth or with very obscure reticulation, the first ter- 

 gite comprising about one third its total length ; ovipositor not exserted. 



Color of head and thorax bluish black, the face often with a slight greenish 

 cast and the sides of thorax sometimes purplish; antennae frequently entirely 

 reddish testaceous but usually with the funicle joints more or less brownish 

 and the rest of the antennae testaceous ; coxae concolorous with the thorax ; 

 all femora dark brownish or blackish ; all tibiae and tarsi testaceous, the tibiae 

 usually somewhat fuscous basally and the tarsal claws dark ; abdomen brownish 

 black, the basal tergite usually with a metallic reflection; fore wing with a 

 large, rounded, fuscous cloud behind the marginal vein extending from the 

 base of marginal to apex of stigmal vein and embracing about three fourths 

 of the width of wing ; rest of fore wing and the hind wing hyaline. 



Male. — Length 1.6 to 2.3 mm. Antennae longer than in female and more 

 hairy, not clavate, 13-jointed, the pedicel as broad as long, ring joints trans- 

 verse but distinct; first funicle joint nearly three times as long as broad, 

 second about twice as long as broad, the sixth about one and one half times 

 as long as broad; club a little longer than the two preceding joints, tapering 

 to a point at apex, 3-jointed, the transverse grooves distinct and deep. Wings 

 hyaline without a cloud. Abdomen with a distinct short petiole, the body of 

 abdomen shorter and usually narrower than the thorax, the apical segments 

 often strongly retracted in dead specimens. Other characters as in the female, 

 except that the legs are somewhat darker. 



