90 - THE CANADIAN ENTOMOLOGIST 



4. Last segment of abdomen short, truncate in female and evenly rounded in 



male as viewed from above hyalinns Fabr. 



Last segment of abdomen comparatively long, rounded or pointed in 

 female, not evenly rounded in male as viewed from above 5 



5. Scutellum broad at apex, rounded or blunt 6 



Scutellum narrow at apex, pointed 11 



6. Abdomen above distinctly marked transversely with black, second and 



sixth segments light coloured sid(B Fabr. 



Abdomen not so marked 7 



7. Last dorsal abdominal segment of female long and distinctly angulate, 



apex less than- a right angle. Dark coloured species. Sternum black, 



connexivum of male spotted 8 



Last dorsal abdominal segment of female rounding, apex greater than a 

 right angle 9 



8. Female segment very acutely pointed, extremely long. Western 



species piinctatus Sign . 



Female segment not acutely pointed, Eastern species bohemanii Sign. 



9. Species small, robust, and dark coloured, mottled on underside of abdomen. 



Very hairy. Connexivum heavily marked parvicornis Sign. 



Species larger, generally lighter coloured, not so hairy. Underside of 

 abdomen not mottled. Connexivum only slightly marked if at all. .10 



10. Species medium sized to small - lateralis Say 



Species much larger lateralis var. validus Uhl. 



11. Postero-lateral angle of metapleura greatly produced. Antennae short, 



last joint comparatively stout. Wings not extending to end of abdo- 

 men. Species small and robust. Densely clothed with fine long 



hairs hirtus Bueno 



Not as above 12 



12. Sternum black. Small species indentatiis Hambl. 



Sternum not black. Larger species scutatus Stal. 



C. hyalinus Fabr. is a well-defined species and readily distinguished from 

 all others by the shape of the last abdominal segment in both sexes. It is cosmo- 

 politan in its distribution, and is the logotype of the genus. I am unable to 

 separate by structural characters the various varieties as listed in Van Duzee's 

 catalogue. 



C. tuherciilatus Hambl. should not be confused with any other species. 

 The very greatly produced antenniferous tubercules serve to distinguish it. 

 In general appearance it greatly resembles indentatiis Hambl., punctatita Sign., 

 and bohemanii Sign. This is a western species, records show it occurs from 

 Washington and Idaho south through Oregon, Nevada and California. 



C. hirtus Bueno is the smallest species in the genus, and appears to be some- 

 what of a degenerate form of parvicornis Sign. The elytra are usually much 

 shortened and appear undeveloped. It is probably limited in its distribution 

 to the northeast. 



C. parvicornis Sign. But little needs to be remarked concerning this species, 

 its short, stout, form being quite characteristic. It is known to occur in 

 Wiishington, California, Arizona, New Mexico, Texas, and southward. 



