164 THE caxadian kntomologist. 



Abdomen petiolate, or the first segment longly petioliform ; the 

 first segment always long and without a delicate carina laterally, 

 or at least the lateral carina? are not sharply defined, much 

 abbreviated, and never extend to the apex of the segment. . .4. 



Abdomen always sessile, never petiolate or with the first segment 

 petioliform ; the first segment never very long and always with 

 distinct lateral carina that extend clear to the apex of the 

 segment; maxillary palpi 6-jointed, labial palpi 3- or 4-jointed ; 

 antennte in 5 12-, in ^ 12- or 13-jointed 3. 



3. Mesopleura with a distinct ridge, carina or crest before the middle 



coxae; recurrent nervure in front wings joining the cubitus always 

 far beyond the middle of the first cubital cell, at about its apical 

 fourth or fifth ; antennae in both sexes 12-jointed, the flagellum in the 

 $ not fringed with fine hairs beneath ; ocelli, except very rarely, 

 arranged in an obtuse triangle . * ., the lateral ocelli being about twice 

 as wide from each other as to the front ocellus or nearly ; mesono- 

 tum and usually also the mesopleura coarsely sculptured ; metathorax 

 more or less coarsely sculptured, opaque or subopaque, never 

 smooth, the cordate area on the posterior face wanting or at most 

 indistinctly defined Subfamily III., Crabroninse. 



4. Mesopleura ^vithoiit a ridge, carina or crest before the middle coxse, 



at most, and rarely, with only a pointed tubercle ; recurrent nervure 

 joining the cubitus at or near the middle of the first cubital cell or 

 somewhat beyond the middle, or at the most never beyond its apical 

 third; antenme in $ 12-jointed, in -( 13-jointed, the flagellum in the 

 latter usually fringed beneath with fine hairs ; metathorax as a rule 

 less coarsely sculptured than in the Crabronina:, often smooth, 

 shining, the cordate area on the posterior face distinct or indistinctly 



defined, never entirely wanting Subfamily IV., Thyreopince. 



3. Mandibles bidentate, rarely 3-dentate or bluntly truncate in 9 ; 

 maxillary palpi most frequently 5-jointed, rarely 6-jointed, the labial 

 palpi 3- or 4-jointed ; first recurrent nervure in front wings received 

 by the first cubital cell at or near the middle, rarely much beyond 

 the middle Subfamily V., Rhopalinas. 



Subfamily I. — AnacrabroniniB. 



The characters made use of in my table of families easily separate 

 this subfamily from the others, the formation of the mesopleura and 



