TABANID^ OF OHIO. 47 



6. Prevailing color of the abdomen black 7. 

 Prevailing color of the abdomen reddish brown - 8> 



7. Segments two to five with small gray triangles superjuinentarius.. 

 Segments three to five with large gray triangles, no triangle 



on the second segment triinaculatus^ 



8. Abdominal segments two to five with medium sized gray 



triangles, wing of female whitish on the disk, all the 

 facets of the eyes of the male of nearly the same size variegatiis. 

 Abdominal segments two to five with large gray triangles, 

 wing of the female not whitish on the disk, large and 

 small facets of the eyes of the male distinctly differen- 

 tiated sulcifrons. 



9. The gray, spots on the sides of the abdominal segments are 



small and do not touch the hind margin 10. 



The gray spots on the sides of the abdominal segments are 



large and touch the hind margin 11. 



10. Third antennal segment long and narrow, prevailing color 



of the abdomen reddish brown longiis.. 



Third antennal segment rather short and wide, prevailing 



color of the abdomen black pumilus. 



11. Gray stripes on the thorax plainly reaching the scutellum viva.w 

 Gray stripes on the thorax obsolete behind nivosus, 



12. Thorax uniformly yellowish pollinose, costal cells yellow costalis. 

 Thorax dark colored with gray stripes, costal cells hyaline lineola 



13. Whole body including the wings black atratus. 

 Whole body inchiding the wings not black 14.. 



14. Abdomen black, wings brownish with a darker spot at the 



bifurcation of the third vein stygius. 



Abdomen brownish, no dark spot at the bifurcation of the 



third vein 15. 



15. Wings hyaline except the costal cells which are brown aiiiericanus. 

 Wings uniformly brownish giganteus. 



16. Cross veins and bifurcation of the third vein margined with 



brown 17. 



Cross veins and bifurcation of the third vein not margined 



with brown 18. 



17. Rather large, grayish species, abdomen not distinctly reddish 



on the sides reinwardtii. 



Medium sized, abdomen broadly reddish on the sides lasiophthahnus. 



18. Third antennal segment deeply excised making the basal pro- ^ 



cess long, general color chocolate brown cerastes. 



Third antennal segment not deeply excised , ,, 19, 



19. Medium sized species, ocelligerous tubercle present 20. 

 Rather small species, no ocelligerous tubercle 21, 



20. Abdomen broadly and distinctly reddish on the sides epistatus. 

 Abdomen narrowly or obsoletely reddish on the sides carolinensis.. 



21. Prevailing color of the whole body bright yellowish bicolor. 

 Prevailing color of the thorax and abdomen black, thinly 



dusted with grayish pollen ohioensis. 



