NORTH AMERICAN HYMENOPTERA. 161 



ridges distinct, though uot strong. Black, including the scutellnm ; mandihles 

 except tips, scape entirely, two spots on pronotum. tubercles in part, extreme tip 

 of fore femora, and medial tibiae except within, hind tibia? entirely, first joint of 

 tarsi, large spot on each side of abdominal segment 2, broadest internally, nar- 

 rower spot on segments 3 and 4 pointed within and a broad band on segment 5, 

 yellow; silvery pubescence in the usual situations including the cheeks; wings 

 subhyaline throughout, with exception of a slightly darker spot at tip of marginal 

 cell. Length 13 mm. 



Canada ; Illinois. A less robust species than mupdarU, with 

 smaller head, striated pronotum and shoit first joint of flagellum. 

 This species seems to be closely allied to, if not identical with C 

 frigidtis Smith. I have not seen the % , which Provancher describes 

 as follows : " Scape black, with a yellow line anteriorly ; thorax not 

 at all maculated, except a large yellow spot on tubercles. Abdomen 

 elongate, with a broad yellow band at the base of fifth segment, the 

 sixth entirely yellow." 



10. Group largior. 



Pygidium ( 9 ) broad, flat, not excavated ; first joint of hind tarsi 

 distinctly longer than the longer spur of hind tibice ; £ flagellum 

 distinctly dilated or expanded; fore tibiie of same sex bearing a 

 large vari-shaped shield, the fifth joint of fore tarsi bearing a peculiar 

 ap])endage. 



35. Crabro largior n. sp. 



9 . — Head finely punctured, very closely so in front ; space between hind ocelli 

 a little less than that between them and the nearest eye-margin ; anterior margin 

 of clypeus not dentate ; pronotum not margined anteriorly, armed with a small, 

 blunt, tooth laterally ; dorsulum with tolerably coarse, more or less separated, 

 punctures; mesopleurss punctured similarly to the dorsulum, but more sparsely 

 above with indistinct striations; middle segment above striated about as in mon- 

 ticola. but less coarsely, and tends to rugose, basally however, are some heavily 

 marked ridges or striae, which become gradually obsolete, the posterior face striato- 

 punctate, its lateral ridges poorly developed extending only about half way to 

 upper surface, sides 7nore or less striated. Black ; mandibles and clypeus more 

 or less, sometimes entirely black, scape entirely or with a spot posteriorly, two 

 large spots on pronotum, tubercles, scutellum more or less, tips of the femora, 

 tibiae except a spot within, tarsi (the apical joints darker however), a sinuous 

 spot on each side of the first dorsal abdomiiial segment, broader spot at each side 

 of second and third, a broad band on fourth and fifth and irregular lateral spot 

 on second, third and sometimes the fourth ventral segments, yellow; head and 

 thorax with tolerably long, shaggy and dense, pale fuscous pubescence not short 

 or stiff on dorsulum ; wings subhyaline, with a yellowish tinge, darker apically, 

 with a fuscous cloud at apex of marginal cell. Length 13-15 mm. 



'^ . — This sex resembles that of pleurnlis, but differs as follows : space between 

 hind ocelli but little less than that between them and nearest eye-margin ; four 



TRANS. AM. ENT. SOC. XXII. (2\) JUNE, 1895. 



