a. c. DAVIS. 269 



59. Longer spur of hind tihiae half as long as heel segment: segment 3 of hind 



tarsi much longer than 5 60. 



Longer spur not equal to half of heel segment; segment 3 of hind tarsi 

 scarcely longer than 5 ' P:tra|>lesiiis Foer. 



60. Basal abdominal segment with a very deep longitudinal furrow; posterior 



median area very broad and with median carina ; mesonotiim and 

 scutellum much punctured, but otherwise smooth. 



■■Trysicampe Foer. 



Basal segment without longitudinal furrow; posterior median area short, 



small and without median carina; mesonotum and scutellum sha- 



greened and punctured ' Nytlioplioiia Foer. 



61. Middle femur with a few teeth at base on lower side. . ''Aeoloinetis Foer. 

 Middle femur without teeth on under side 62. 



62. Posterior trochanter with a strong, blunt, projecting tooth beneath base of 



femur; third discoidal cell broad; clypeus scarcely separated from 



face ; ovii)ositor curved upward Volucris Davis. 



Posterior trochanter without tooth beneath 63. 



63. Segment 2 without thyridia at base, or they lie very close to the base and are 



quite invisible 64. 



Segment 2 with plain thyridia 80. 



64. Humeral cross-nervure broken above the middle 65. 



Humeral cross-nervure broken at or below the middle 66. 



65. Mesonotum trilohed; area supero-media shorter than the postero-raedia ; hu- 



meral ci'oss-nervure broken but little above the middle. 



"••Polypystis Foer. 

 Mesonotum not divided; area supero-media longer than the postero media ; 

 humeral cross-nervure broken far above the middle. 



•• Xenonasfes Foer. 



66. Metanotum entirely areolated SycIiiiO|>oi't/ii!!> Foer. 



Metanotum not entirely areolated 67. 



67. Eidge of vertex broken in the middle j"'- Astlieiiara Foer. 



Eidge of vertex not broken in the middle 68. 



68. Base of discoidal cell not as broad as transverse median nervure. 



t-€aiiipory<'hus Foer. 

 Base of discoidal cell as broad as, or broader than transverse median ner- 

 vure 65). 



69. Areolet not quite wanting, but half open at apex 70. 



x^reolet usually entirely wanting 71. 



70. Transverse median nervure uniting before basal ; base of discoidal cell only 



twice as broad as transverse median nervure; areolet very small; 

 spiracles of segment 1 lying in or back of middle. 



*Trapez«cora Foer. 



Transverse median nervure uniting far back of basal; base of discoidal cell 



at least three times as broad as the transverse median nervure ; areolet 



very large, short petiole, wide open ; spii'acles lying in front of the 



middle -' ltliigelii!« Foer. 



71. Clypeus emajginate, almost semicircular on front edge . .('acotropa Foer. 

 Clypeus not so emarginate .72. 



72. Metanotum not areolated 73. 



Metanotum more or less areolated 74. 



TRANS. AM. ENT. SOC. XXIV. SEPTEMBER, 1897. 



