NORTH AMERICv^N HYMENOPTERA. 141 



separating the upper surface from the posterior face well developed, medial furrow 

 broadened, widened medially, upper surface much more coarsely striated than in 

 atriceps and the stripe fewer, posterior face finely rugose, distinctly ridged laterally, 

 sides rather indistinctly striated : abdomen more finely punctured than in atriceps. 

 Black, including the mandibles ; scape more or less, two small spots, widely sepa- 

 rated, on pronotum, tubercles, metanotum. spot on fore and medial femora at 

 apex, sometimes lacking, tibiae externally, sometimes the hind ]5air in greater 

 part, a large spot on each side of dorsal abdominal segments 2 5. more or less 

 pointed internally, except those on the fifth, which are truncate and always sepa- 

 rated, yellow ; tarsi black , wings pale fusco-hyaline, nervures and stigma black. 

 Length 6.5-8 mm. 



% • — Head finely and closely punctured, the hind margin tolerably well mar- 

 gined ; space between hind ocelli apparently slightly greater than that between 

 them and the nearest eye-margin ; middle segment above coarsely rugose, poste- 

 rior face with somewhat irregular, coar.>5e, transverse striations, the lateral ridges 

 present but imperfectly developed, sides strongly striated; first joint of medial 

 tarsi about as long as the three following united, less dilated medially than in 

 atriceps, second joint curved and produced at apex ; abdomen punctured as iu the 

 female ; colored and marked like the female, the spots on pronotum sometimes 

 absent, those on tlie abdomen smaller than in the other sex and always widely 

 separated. Length 6-7 mm. 



Maine; New Hampshire; Pennsylvania; Illinois (Roberteon); 

 South Dakota (Aldrich). The .separated spots on fifth abdominal 

 segment, coarser sculpture and darker wings are points in which this 

 species differs from atriceps. 



8. Crabro corriigatiis Pack. 



Cniljru corniciatus Packard, 1. c, p. 107, ? . 



9. — Space between eyes at base of clypeus somewhat less than the combined 

 length of flagellum joints 1 and 2, the space between hind ocelli slightly greater 

 that between them and the nearest eye-margin ; pronotum with the transverse 

 impression broad, especially toward the sides, sides not deep, the lateral tooth 

 small and blunt; dorsulum finely striato-punctate, most closely anteriorly, scu- 

 tellum more coarsely so ; mesopleurse finely striato-punctate, more finely than the 

 posterior portion of the dorsulum; middle segment above covered with very 

 coarse, irregular folds or rugge, who.se strength varies, posterior face tolerably 

 well enclosed by a surrounding ridge, with coarse, transverse striations on apical 

 portion, sides finely, though distinctly striated : abdomen very finely and closely 

 punctured. Black ; large sjmt on mandibles basally, scape entirely or in part, 

 large spots on pronotum. tubercles, metanotum, tips of femora more or less, tibia- 

 entirely or spotted internally, sometimes the first tarsal joint in part, and large 

 .spot at each side of dorsal abdominal -segments 2 5, those on the latter .separated 

 sometimes very nearly united, though usually well separated, yellow ; tai-si testa- 

 ceous; wings subhyaline. a little darker apically. nervures and stigma testaceous. 

 Length 6-7 nun. 



% . — Head strongly and sharply margined posteriorly ; pronotum broadly fur- 

 rowed as in the 9 '- middle segment with the ridge enclosing posterior face very 

 strong, the latter with coarse, transverse striations throughout, sides rather 



TRANS. AM. ENT. .SOC. XXII. MAY. 1895. 



