396 PRGCEEDI^TQS OF THE NATIONAL MUSEUM. 



5. Male hypopygium incrassated, the ninth tergite very tumid, the two halves 



separated by a deep median longitudinal furrow N. cornifera (p. 896). 



Male hypopygium small, not conspicuously iucrassated__y. tenuis (p. 397). 



6. Antenual segments uniform in color 7. 



Antennal segments bicolorous 16. 



7. A velvety black spot at the ends of the lateral praescutal stripe 8. 



No such spot 9. 



8. Occiput with a nnrrow brown median line A''. cuJinota (p. 396). 



Occiput without such a line N. ininctiun (p. 397). 



9. Occiput opaque with a shining triangular median spot 10. 



Occiput shining 13. 



10. A black spot at the ends of the V-shaped suture N. fcrniginca (p. 397). 



No such spot 11. 



11. Antennae entirely yellowish N. fcstina (p. 397). 



Antennal flagellum dark brown or black 12. 



12. Stigma pale, brownish yellow j\". occipitalis (p. 397). 



Stigma dark, blackish brown (IJegional) N. graciliconus (Loew). 



13. Antennae yellowish N. fcstina (p. 397). 



Antennal flagellum dark brown or black 14. 



14. Head with a shining triangular spot N. occipitalis (p. 397). 



Head unicolorous 15. 



15. Head and thorax yellowish, almost opaque ; color in life strongly greenish 



N. tenuis (p. 397). 



Head orange except the lateral margins of the vertex ; thorax shining 



N. social is (p. 397). 



16. Segments of the flagellum dark brown or black at the base; antennae with 



13 segments 17. 



Segments of the flagellum yellow at the base; antennae with moi'e than 

 13 .segments 18. 



17. Wings strongly tinged with yellow; thorax shiny reddish without distinct 



stripes ; antennae of the male elongated, strongly bicolorous 



N. xanthosignia (p. 398). 



Wings grayish, more j^ellowish basally ; thorax with rusty gray pruinose 



stripes, the intermediate one with a narrow black median vitta ; antennae 



short in both sexes, indistinctly bicolorous N. calinota (p. 396). 



18. Stigma yellowish brown; wing apex not dorkeued JV. cucera (p. 396). 



Stigma dark brown wing apex distinctly infuscated N. polymcra (p. 397). 



The immature stages of the species of Nephrotoma are spent in 

 earth, decaying wood, and moss. 



* NEPHROTOMA CALINOTA Dietz. 



Plummer's Island, June 8, 1913, A. Wetmore; July 14, 1907, A. K. 

 Fisher. 



* NEPHROTOMA CORNIFERA Dietz. 



Four-mile Run, Virginia, July 2-1, 1915, Alexander. 



* NEPHROTOMA EUCERA Loew. 



Forest Glen, Maryland, May 31, 1914, F. Knab: Great Falls, Vir- 

 ginia, June 14, 1914, L. O. Jackson; Plummers Island, May 24, 

 1902, R. P. Currie; May 24, 1914, McAtee: June 9, 1914, R. C. Shan- 

 non ; Falls Church, Virginia, July 14, 1913, F. Knab ; Mount Vernon, 

 Virginia, June 9, 1918, McAtee. 



