16S THE CANADIAN ENTOMOLOGIST. 



tooth or tubeixle, so that the clypeus anteriorly appears tnden- 



tate Thyreus, Lepel. et Br. 



J Type C. clypeatLis, Schb., $ . ) 

 ( -= C. vexiilatus, c^ . f 



4. Scrobes normal, 7iot bounded by a transverse carina superiorly. ... 5. 

 Scrobes deep, bounded by a transverse carina superiorly. 



Mesonotum rather coarsely confluently punctate, but without longi- 

 tudinal aciculations, except sometimes slightly posteriorly and 

 on the scutellum, the mesopleura at the most with some striae 

 superiorly ; metathorax at sides and posteriorly striated, the 

 metanotal area coarsely retriculated or alveolate ; third antennal 

 joint longer than the fourth, scarcely twice as long as the pedicel, 

 joints 4-5 about equal ; abdomen shining, at the most sparsely 



microscopically punctate Ectemnlus, Dahlb. 



['I'ype C. guttatus, Lind.] 



5. Mesonotum ?iot longitudinally striate or aciculate, either finely or 



coarsely punctate ; clypeus more or less strongly produced medially 



at apex 6. 



Mesonotum longitudinally striate or aciculate, as well as the scutellum, 

 the mesopleura and the metathorax, the anterior part of the meso- 

 notum especially laterally more or less transversely striate ; clypeus 

 not strongly produced medially, but with a median ridge or carina 

 on its disk ; third joint of antennae long, about as long as joints 

 4-5 united ; abdomen shining or subopaque, finely coriaceous, 

 or microscopically punctate, the first segment highly 



polished Crabro, Fabr. 



[Tpye C. fossorius, Linne.] 



6. Mesonotum on disk and posteriorly sparsely punctate, but anteriorly 



and at sides closely confluently punctate, subopaque ; mesopleura 

 neither strongly nor distinctly striate, except superiorly ; metathorax 

 with the basal area punctate, not striate, the posterior face rugulose, 

 slightly striate at apex, the pleura smooth, delicately aciculated ; 

 clypeus similar to Crabro ; third antennal joint not so elongate but 

 longer than the fourth ; abdomen finely coriaceous and microscopic- 

 ally punctate Hypocrabro, Ashm., n. g. 



[Type C. lo-maculatus. Say.] 



Mesonotum closely confluently punctate, opaque or subopaque, the 

 mesopleura and metathorax, including the basal area, strongly 

 striate ; clypeus similar to Crabro. 



