260 BULLETIN 45, UNITI^D STATES NATIONAL MUSEUM. 



Abdomen polished, the first segment and the second at extreme base, 

 striated, the horn extending forward to vertex of liead. Legs brownish- 

 X)iceons, the coxa? bhick, the trochanters, base of tibia'- and tarsi yel- 

 lowish, the anterior tibia^ being mostly yellow except above atthe middle. 



Habitat. — Washington, D. C. 



Type in Coll. Ashmead. 



ACEROTA Forster. 



Hym. Stud, ii, p. 107 (1856). 



(Type not described ) 



Head transverse, ihe vertex subcouvex, the occiput margined ; ocelli 

 3, in a curved line, the lateral distant from the margin of the eye, but 

 slightly nearer to it than to the front ocellus; eyes rounded. 



Autenn* inserted just above the clypeus, 10-jointed, in $ terminating 

 in a 4-joiuted club, the pedicel longer than the first funiclar Joint; in S 

 subfiliform, the pedicel not longer than the first funiclar joint, the club 

 5- or (J-jointed, the terminal joint more than twice as long as the penul- 

 timate and scarcely thicker than the first fnniclar joint. 



Th(u-ax ovate, the mesonotal furrows distinct, deep, and entire; 

 scutellum convex or subconvex, separated from the mesonotum by a 

 transverse line, and with a frenum or carina posteriorly; metathorax 

 rather short. 



Front wings with the submarginal vein terminating m a stigma at 

 about one-third the length of the wing. 



Abdomen long-oval, the first segment not or scarcely longer than 

 wade, striated, the second larger, occupying about half of the remain- 

 ing surface, the following segments short. 



Legs clavate, the tibial spurs 1, 1, 1, the basal joint of posterior 

 tarsi, about 2i times as long as the second, 2 to -4 subequal, the last 

 not quite as long as the second. 



Closely allied to Inostemma, but the fenuile without- a horn at the 

 base of the abdomen, the mesonotal furrows more sharply defined, the 

 second funiclar joint in the male longer and cylindrical. 



TABLE OF SPECIES. 



Head and thorax closely piinctulate. 



Hind coxif alone l)lack 2 



All coxa> black. 



Mesonotum Avith a distiuct lonji,itudinal carina at the base of the middle lobe, 

 with irregular rnised lines on either side of it. 



Antenna* brown-black A. cixidomyije, sp. nov. 



Mesonotum with iu> raised lines at l)ase of the middb' lo]>e. 



Legs rufoTis, the feiuora aud sometimes the tibiie fuscous or l>lack. 



Face with fine longitudinal slriic toward base* of antenna*, the middle of 

 froiis nearly smooth, shining; antenna- dull rufous. 



A. FLOKIDAXA Ashm. 



