l6o PSYCHE [August 



Face with blackjpubescence ........... 32. 



31. Legs completely black ......... 32. polita Cress. 



Legs densely pruinose ......... 46. striolata Cam. 



45. ckaiiipioni Cam. 

 25. flacida Sm. 



26. saevn Sm. 

 16. frocera Dahlb. 



IS- 

 40. 



32. Prothorax transversely striate .... 



Prothorax smooth ...... 



2)'^. Abdomen almost wholly red .... 



Petiole and apical part of abdomen black . 



34. Legs at least in large part red .... 

 Ground color of legs wholly black or piceoiis . 



35. Head and clypeus black; metanotum at least centrally with transverse striae . 36. 

 Metanotum sharply, densely, and obliquely striated ; face and clypeus silvery 



19. aberti Hald. 



36. Sides of thorax with markings of silvery pubescence; central part of metanotum pu- 



bescent 37. 



Pleurae and metanotum not pubescent, pleurae with three large silvery pruinose spots 



60. femiir-rubritin Fox 



37. First joint of petiole black, t. e., with more black than second joint . . . 3S. 

 First joint of petiole with more red than second joint; species of 16-25 imn- 



29. priiiiiosa Cress. 



38. Pleurae with dense matted pubescence; species of 35 to 40 mm. 24. yarrowi Q\-&'&%. $• 

 Pleurae with sparser more erect hairs; species under 30 mm. .... 39. 



30. Base of femora black; thorax not densely pubescent above . . 21. breviceps ^xx\. 

 Four anterior legs red; thorax densely pubescent above . . . 58. comanche Qmx\. 



40. Wings yellowish or fulvous ........... 41. 



Wings dark-violaceous to subhyaline ......... 42. 



41. Head and thorax matte-black, sparsely black pilose . . 31. extremitata Cress. 5. 

 Head and thorax bluish, densely fusco-pilose .... 44. zaiithoptera Cam. 



42. Mesopleurae with spots or oblique stripings of silvery golden color . . . 43. 

 Pleurae uniform in color, not with pubescent markings ...... 61. 



43. Thoracic notum with appressed sericeous pubescence and erect hairs . . . 44. 

 Thorax devoid of dense appressed pubescence but often with sparse to dense hairs 



and sometimes more or less pruinose ......... 48. 



44. Central space of metathorax closely pubescent .... 24. v«r;'c>w/ Cress. 

 Metathorax not pubescent centrally .......... 45. 



45. Abdomen largely red, the segments with a black dorsal spot . .61. uasalis Prov. 

 Abdomen nearly or wholly black .......... 46. 



46. The dilated part of the second segment except its hind margin red i8. arvcnsis Lep. 

 Abdomen completely blue-black; third submarginal narrow; the sericeous pubesence 



confined to the front part of the thorax ........ 47. 



47. Metapleurae coarsely striated ; hind coxae covered with silvery pubescence 



37. miliaris Cam. 

 Metapleurae finely rugulose ; hind coxae silvery above only . 13. abbreviaia Fabr. 



48. Central part of metathoracic disc rugulose, scutellum with longitudinal striae 



20. fra gill's Sm. 

 Central part but little roughened, generally more or less striated .... 49. 



49. Small species clothed with silvery cinereous pubescence; metanotum with well-marked 



oblique striae generally connected by a median line . . 33. vulgaris Cress. 



