316 [September 



thorax yellowish-rufous, its base blackish, the elevated lines not well 

 defined, the lateral tubercles wanting'. Wings subhyaline, slightly 

 stained with fuscous, iridescent ; nervures and stigma fuscous ; areolet 

 minute, quadrate. Legs slender, yellowish-rufous, the four anterior 

 coxae and trochanters white beneath, black above, as well as the poste- 

 rior trochanters above; posterior tibiaj and tarsi more or less obfuscated. 

 Abdomen elongate and slender, subcylindric, shining ; basal segment 

 linear; apical segments polished, slightly obfuscated. Length 3} lines; 

 expanse of wings 5 lines. 



^a6.— Virginia. Dr. Thomas B. Wilson. 



Closely allied to M. thoracic us, but is much smaller and slenderer, 

 the antennae are entirely black and the posterior legs are differently 

 colored. 



h. Mesostenus? fulvus, u. sp. 



Fulvous; head black, the face and orbits, white: antennae black with a white 

 aunulus : wings hyaline; posterior tarsi white. 



Male. — Fulvous, shining ; head black, the face, orbits very broad on 

 the cheeks, clypeus, mandibles and palpi, white; antennae rather longer 

 than the body, porrect, black, the 11th to 13th or 14th joints white, 

 the basal joint beneath with a white spot. Thorax opaque above, the 

 dorsal lines very deeply impressed and black ; tegulae, a sutural line 

 before and a short line beneath the anterior wings, line on the collar 

 extending down its sides, a line on the pleura in front and a spot before 

 the middle coxaj, white ; scutellum slightly convex, fulvous, the lateral 

 carinje in front white, the space on each side blackish ; postscutellum 

 with a fulvous transverse spot; metathorax fulvous, blackish at extreme 

 base, the posterior face tinged with whitish, the elevated lines sharply 

 defined, the lateral tubercles strongly developed, rather obtuse and 

 white. Wings hyaline, iridescent; nervures and stigma blackish-fus- 

 cous, the latter with a longitudinal, fulvous line through the center; 

 areolet small, quadrate, the outer nervure indistinct or wanting. Legs 

 fulvous, the four anterior pair yellow in front, the posterior pair very 

 long, somewhat tinged with brown ; the four anterior coxae and tro- 

 chanters, and the 2nd, 3rd and 4th joints of the posterior tarsi, pure 

 white. Abdomen rather short; a little longer than the head and tho- 

 rax, subovate, shining, reddish-fulvous; basal segment about as long as 

 the second, apical half bi'oad. convex, petiole short, stout, flattened ; 



