No. 22.] HYMENOPTERA OF CONNECTICUT. 245 



11. Tarsal claws pectinate in one or both sexes; abdomen sub- 



sessile; spiracles of propodeum linear; third discoidal cell 

 not or but slightly narrowed at base, cubitodiscoidal vein 

 straight and not broken by a ramellus; abdomen wider 

 than thick or depressed in male, acuminate and acutely 

 pointed at tip in female, with an oblique impressed line 

 on each side of segments two to four above; scutel un- 

 arm.ed; body smooth and polished; hind femora short and 

 robust, tarsal claws in male pectinate, in female toothed 

 near tip; second joint of hind trochanters swollen at tip 



beneath; eyes not emarginated Ceratogastra p. 273 



Tarsal claws not pectinate; abdomen subpetiolate; spiracles 

 of propodeum oval; eyes entire; third discoidal cell nar- 

 rowed at base, cubitodiscoidal vein much curved up- 

 ward, and generally with a ramellus arising from it before 

 its middle Exetastes p. 274 



12. Hind femora without a tooth beneath 13 



Hind femora with a tooth beneath; areolet wanting; hind 



trochanters shorter than their coxas Pristomerus p. 274 



13. Marginal cell subtriangular or almost trapezoidal 14 



Marginal cell lanceolate; median and submedian cells of fore 



wings not confluent 16 



14. Spiracles of first dorsal abdominal segment situated beyond 



or back of the middle 15 



Spiracles of first dorsal abdominal segment situated before 

 the middle Orthopelma p. 275 



15. Antennas remote from each other at the point of insertion; 



sternum wider than long; propodeum shorter than thick 

 or high, third discoidal cell rectangular, scarcely narrowed 



at base; cubitodiscoidal vein straight Porizon p. 275 



Antennae not remote from each other at the point of inser- 

 tion; sternum longer than broad, propodeum scarcely or 

 only a little longer than thick or high; third discoidal cell 

 more or less narrowed at base; cubitodiscoidal vein 

 arched above Porizonidea p. 275 



16. Spiracles of propodeum round ^ 17 



Spiracles of propodeum usually oval or elongate 42 



17. Areolet small, subtriangular, subpentangular or wanting 18 



Areolet large, rhomboidal; ovipositor and male cerci ex- 



serted Mesochorus p. 277 



18. Clypeus with a suture or depression between it and face . 19 

 Clypeus with an imperfect suture between it and face, or 



completely fused with the latter 20 



19. Abdomen sessile or subsessile, more or less broader than 



thick or depressed; areolet oblique or wanting 



'^ Plectiscidea p. 275 



