936 CHARLES PauL ALEXANDER 
14. Head with a shining triangular spot. [Pachyrrhina occipitalis Loew. Berl. Ent. Ztschr., 
VOL Sap NiOD se Ml SGAs] Ear eee en wel ots Leet oR hen a ence aa N. occipitalis (Loew) 
Head! unic olorous issn die leis 8 bob are, apeusleie ute. ah eos ere sl CU CIES ER ee ee ge 
15. Wings strongly tinged with brown, especially along the costal region. eins 
okefenoke Alex. Wash. Univ. Studies, p. 97-98. 1915.].......... N. okefenoke (Alex.) 
Wings not strongly brown along the costal region..........................22.... 16 
16. Head and thorax vellowish, almost opaque; color in life strongly greenish. [| Pachyrrhina 
tenuis Loew. Berl. Ent. Ztschr., vol. 7, p. 297. 1863.] (Plate XLIV, 199.) 
N. tenuis (Loew) 
Head orange except the lateral margins of the vertex; thorax shining. [Pachyrrhina 
sodalis Loew. Berl. Ent. Ztschr., vol. 8, p. 64. 1864.] ee. N. sodalis (Loew) 
17. Segments of flagellum black at the base. ecco ri eos 18 
Segments of flagellum yellow at the base.............. 0.00. ee cece eee eee eee 20 
18. Wings strongly tinged with yellow; occiput without a clear, shining , triangle. 
[Pachyrrhina xanthostigma Loew. Berl. Ent. Ztschr., vol. 8, p. 65. 1864.] (Plate 
XUV DOME ip 6 ee Ue Tere ER AR eon Le a ae N. xanthostigma (Loew) 
Wings not strongly tinged with yellow; occiput with a clear, shining triangle......... 19 
19. Costal region hyaline; stigma dark brown. [Pachyrrhina abbreviata Loew. Berl. Ent. 
Zischriscvoleds spy 290% ml Gdeale wk te seca nn OO. Nedeter tie aan N. abbreviata (Loew) 
Costal region darker; stigma yellowish brown. [Pachyrrhina suturalis Loew. Berl. Ent. 
Tischrevolaig pyc oe ml SOdcancieren eo a oe ee N. suturalis (Loew) 
20. Antennae with 13 segments. [Pachyrhina breviorcornis Doane. Ent. News, vol. 19, 
1 OPH LACS RCA shia 270 egal a aN ep tart Yea Ra Me ee lB N. breviorcornis (Doane) 
Antennae with more than U3')segments. 20) 2902 eee 21 
21. Stigma yellowish brown; wing apex not darker; antennae of male 19-segmented. | Pachyrr- 
hina eucera Loew. Berl. Ent. Ztschr., vol. 7, p. 296. 1863.]...... N. eucera (Loew) 
Stigma dark brown; wing apex distinctly darkened; antennae of male 16-segmented. 
[Pachyrrhina polymera Loew. Berl. Ent. Ztschr., vol. 7, p. 297. 1863.] 
N. polymera (Loew) 
After the above key was completed, Dietz (1918) published an extensive 
revision of the American species of the genus. A number of his new 
species are found within the faunal limits of this paper. The more salient 
characters of the regional species are here briefly summarized, and these 
species should be considered in addition to the key. 
Nephrotoma perdita (Dietz). (Pages 116-117 of reference cited.) 
Yellow; mouth parts and palpi yellow; occiput with a shiny brown pentagon; thoracic 
stripes black, narrowly margined with rusty, the lateral stripes curved outward and ending 
in an opaque black spot; wings grayish subhyaline, stigma brownish black. Wing of female, 
14.5 mm. (Manitoba, August.) 
N. hirsutula (Dietz). (Pages 118-119 of reference.) 
Very closely resembling N. macrocera, but with the wings sparsely pubescent. Eighth 
sternite of male deeply emarginate behind and with a digitiform lobe from the base of the 
notch. Wing of male, 12.6 mm. (Pennsylvania, May.) 
N. urocera (Dietz). (Pages 119-120 of reference.) 
N. cornifera (Dietz). (Pages 120-121 of reference.) 
These two species are close to N. okefenoke but are easily separated by the male 
genitalia. They are from Virginia and North Carolina. 
N. calinota (Dietz). (Pages 121-122 of reference.) 
Yellow; antennal flagellum bicolorous; frontal prolongation of head dark brown medially; 
occiput opaque with a brown line; thoracic stripes silvery gray pruinose, the lateral stripes 
