196- AMERICAN HYMENOPTKRA. 



11. Face strongly protuberant anrl coarsely punctured ; clypeus wanting, or 



small - 12. 



Face not strongly protuberant, or if so the clypeus is distinct 13. 



12. Scape small, or normal size EXOCHINI. 



Scape large and much elongated OBTHOCENTRINI. 



13. Upper tooth of mandibles bidentate; abdomen sessile, basal segment nearly 



quadrate B ASSINI. 



Mandibles bidentate. seldom toothless 14. 



14. Posterior tibiae without spurs, or at most with a single small one. 



EXENTERINI. 

 Posterior tibiae with two spurs • • • -15. 



15. Abdomen sessile, or subsessile ; ovipositor usually long 16. 



Abdomen petiolate, or if sessile, the ovipositor is short 17. 



16. Dorsum of abdominal segments usually uneven because of impressions; seg- 



ments usually plainly punctured PIMPLINI. 



Dorsum of abdominal segments without impressions and seldom much punc- 

 tured LISSONOTINI. 



17. Hind legs long and much thickened ; last ventral segment of the abdomen 



lanceolate, projecting ; antennae, short and straight AC^NITINI. 



Hind legs not both long and thick; antennae not short and straight 18. 



18. Mandibles projecting forward and forming a cavity with the clypeus, which 



is impressed or excavated ; head cubical XORINI. 



Mandibles closing and not forming a cavity with the clypeus 19. 



19. Head small, face usually glabrous; clypeus large, about as long as broad. 



arched and impressed at sides; second transverse cubital nervure often 



wanting ; small insects PLECTISCINI. 



Head and clypeus normal 20. 



20. Areolet large, rhomboidal ; % with two styloid jirojections at apex of ab- 



domen MESOCHORINI. 



Areolet not large and rhomboidal : % without styloid projections 21. 



21. Scutellum terminates in a very long spine AGRIOTYPINI. 



Scutellum does not terminate in a spine 22. 



22. Wings wanting, or short and imperfectly developed, in the last case without 



stigma (it may be that the winged %, with the unareolated metanotum 



exists) PEZOM ACHINI. 



Wings fully developed, and if not there is a stigma 23. 



23. Ovipositor distinctly projecting; no lunulae* on the third abdominal segment 



and seldom on the second ; areolet pentangular, closed, or open behind. 24. 



Ovipositor not or hardly projecting, seldom prominently so, in which case the 



luuulae are always present 26. 



24. Areolet open behind HEMITELINI. 



Areolet closed 25. 



25. Metanotum with a well-formed superior median area ; petiole with two carinas 



PHYGADBUONINI. 

 Metanotum without a well-formed superior area; petiole without carinae. 



^ CRYPTINI. 



* By lunula is meant a small shining spot a little beyond the spiracles of the 

 second and third abdominal segments and always a little farther away from the 

 margin. 



