No. 22.] HYMENOPTERA OF CONNECTICUT. 749 



emarginate, with a rather dense apical fascia of dull whitish 

 pubescence; front usually with an opaque blackish patch 



canadensis 



8. Clypeus subquadridentate, with a median emargination and 



two lateral teeth albiventris 



Clypeus entire; scopa sometimes blackish on fifth and sixth 

 ventral segments; ventral scopa white piunila 



9. Mandibles quadridentate; length 11 mm major 



Mandibles tridentate; length 8 mm atriventris 



Males. 



1. Apical margin of seventh dorsal abdominal segment entire 



or slightly emarginate, of sixth entire 2 



Apical margin of seventh dorsal abdominal segment bidentate 4 



2. Mid tarsi simple 3 



Mid tarsi broad, 3-sided; third antennal joint as long as 



fourth; hind metatarsi arcuate, clavate; hind spur twice 



as long as its fellow bucephala 



3. Mid femora produced beneath; fourth antennal joint as long 



as second and third combined; hind metatarsi toothed 



beyond middle; pubescence mixed with black lignaria 



Mid femora simple; third antennal joint longer than fourth; 

 pubescence pale albiventris 



4. Sixth dorsal abdominal segment more or less notched me- 



dially, not strongly sinuate or dentate; first ventral seg- 

 ment entire 5 



Sixth dorsal abdominal segment entire medially, strongly 

 sinuate and strongly dentate laterally; front with two 

 tubercles, one above the other conjuncta 



5. Antennae filiform 6 



Antennae moniliform; hind metatarsi arcuate, clavate. .simillima 



6. Hind metatarsi simple 7 



Hind metatarsi dentate near middle of inner margin; hind 



spurs equal in length, and nearly one-half length of hind 

 metatarsi vicina 



7. Sixth dorsal abdominal segment strongly notched; dull 



greenish 8 



Sixth dorsal abdominal segment at most with a shallow 

 notch; brassy green; margin of sixth abdominal segment 

 stramineous ^ ,.pumila 



8. Length more than 7.5 mm 9 



Length less than 7.5 mm., or 6.5-7 inm rustica 



9. Length 10 mm major 



Length 8 mm atriventris 



