NORTH AMERICAN HYMENOPTERA. 277 



Genus 6, APTEROOYNA Latr. 



Head roundly transverse ; antennas of male nearly as long as the 

 body ; thorax more or less ovate, metathorax bidentate posteriorly ; 

 abdomen petiolate, basal segment globose, second transversely sub- 

 globose ; wings hyaline, one submarginal cell, entire neuration con- 

 fined to the basal area (fig. 21) ; thorax of the female divided into 

 two 2)arts ; basal segment of abdomen similar to the male, second 

 large and subsessile with the third. Unrepresented. 



Fig. 21. 



Genus 7, BRADYNOB^NUS Spin. 



Female. — Head quadrate, mandibles elongate, arcuate, palpi fili- 

 form, the maxillary palpi 8-jointed ; the labial palpi 2-jointed, very 

 short ; thorax divided in two parts ; femora and posterior tibiae 

 dilated ; abdomen petiolate, elongate, regularly ovate. Unrepresented . 



Genus 8, MYRMOSA Latr. 



Head subglobose ; stemmata placed in a triangle on the vertex ; 

 eyes small, round and lateral ; antennae subfiliform, in.serted in the 

 female at each side of the base of the clypeus and approximate ; in 

 the male they are wider apart ; the clypeus triangular and longitu- 

 dinally carinate in the female ; in the male transverse and plane ; 

 mandibles unidentate and acuminate in the female ; large and tri- 

 dentate in the male ; the thorax longitudinally quadrangular, the 

 anterior angles rounded ; the metathorax truncate in the female ; the 

 thorax ovate in the male ; the collar transverse, curving towards the 

 base of the wings posteriorly, not reaching them ; the anterior wings 

 with one marginal and four submarginal cells, the second submarginal 

 triangular, receiving the first recurrent nervure near its centre; the 

 third quadrate, receiving the second recurrent nervure at about one- 

 third of its length, the fourth extending to the apex of the wing ; 

 the legs spinose ; abdomen of the female ovato-conical, the first seg- 

 ment somewhat narrower than the second ; the abdomein of the male 

 oblong, the margins of the segments crenate, the last concave above 

 and tridentate at its apex, which is truncated. 



