128 INSECUTOR INSCITI^ MENSTRUUS 



4. Abdomen shining steel blue; third and fourth segments with 



black pile (California, Washington) chalybescens Will. 



Abdomen blackish with pale yellow or brownish pile 5 



5. Tibiae and tarsi largely yellow, face but little protruding 



downward (lasiophthalma complex Alaska, Washington, 

 Oregon, Colorado, New Hampshire, North Carolina), 



lasiopthalma Will. 

 Tibiae largely black; face much protruding downward (Ore- 

 gon, Washington) ferruginea Lovett. 



6. Fore coxa with a short, but distinct, spur on outer anterior 



corner (western America spp.) 7 



Fore coxa without spur 8 



7. Legs entirely black (Idaho) aldrichi Hunter. 



Apices of tibiae yellowish (Brit. Col.; Idaho) columhiae Curran. 



8. Pile on pleurae luteous ; no bristle-like hairs on thorax 



(Idaho)' Aorella, n. sp. 



Pleural pile black; bristle-like hairs on alar callosities and 

 scutellum 9 



9. Small species, 7-8 mm. ; antennae black (Alaska) borealis Coq. 



Larger species, 10-12 mm.; antennae usually not pure black 10 



10. Antennae and legs, including pile on the legs, entirely black; 



wings smoky (Massachusetts) hiawatha, n. sp. 



Antennae brown or reddish yellow ; pile on coxae whitish or 



luteous 11 



11. Wings rather strongly infuscated ; dorsum of thorax with a 



well defined band of black pile ; face usually with a few long 



hairs (Oregon, Washington) nigrointtata Lovett. 



Wings but little infuscated ; pile on mesonotum concolorous 12 



12. Face scarcely concaved between antennae and tubercle. See 



female (Ontario, New York, New Hampshire, North 



Dakota) prilliaensis Curran 



Tubercle very large and convex (California) baroni Will. 



13. Thoracic pile black, the pile on the venter alone being pale ; 



general color dark blue (Washington) burkei, n. sp. 



Pleural pile more or less light colored ; general color black, 

 or greenish black 11 



14. Legs distinctly bicolored ; arista shorter than width of frons 



measured across lunule ; mesonotal pile entirely luteous 



(eastern United States) priwovcris Shann. 



Legs black, merging into dark brown ; arista as long as, usual- 

 ly longer than, width of frons ; mesonotal pile usually 

 brownish or partly black 15 



'C. hiintcri Cunan (Manitoba, Canad, Knt., May, 1922) probably comes here. 



