AKT. 15«. EEVISION or SUBFAMILY PLATYGASTERINAE FOUTS. 25 



Head broadly transverse to subquadrate; face with a truncate or 

 emarginate projection between the antennae; lateral ocelli close to or 

 remote from the eye margin; mandible bidentate, the teeth equal or 

 unequal; antennae in female 10-jointed, clavate, gradually increasing 

 in thickness toward the tip; antennae in male 10-jointed, filiform, 

 w^ith the fourth joint deformed in some way, usually emarginate 

 below at the base, sometimes widened in the middle with a sharp 

 edge below^; thorax short to moderately elongate, the notauli either 

 absent, incomplete, or complete; if complete they may be parallel 

 and widely separated at the base, or converging posteriorly; mesono- 

 tum with a wide or narrow suture separating it from the scutellum; 

 scutellum fiat or convex, margined laterally, sparsely pubescent or 

 without hair, unarmed or with a short tubercle on its posterior dor- 

 sal surface; this tubercle consisting of the upturned edge of the dor- 

 sal plate of the scutellum ; propodeum short, with two parallel, median, 

 longitudinal, elevated carinae; tarsi 5-jointed; wings, pubescent, cil- 

 iate at the margins, veinless; abdomen in female as short as the tho- 

 rax to several times as long as the head and thorax united, depressed; 

 abdomen in male usually about as long as the thorax; first and sec- 

 ond tergites sometimes sparsely pubescent, the former laterally, the 

 latter basally; second tergite in both sexes with two more or less 

 distinct basal foveae, their position indicated by an emargination at 

 the anterior border of the segment. 



TABLE TO SPECIES. 



1. Scutellum granular or shagreened 2. 



Scutellum polished on its dorsal surface, unsculptured 26. 



2. Occiput smooth, not distinctly sculptured 3. 



Occiput striate 4 . 



Occiput granulose or shagreened 14. 



3. Mesonotum shagreened; notauli complete, nearly parallel; foveal striations on 



second tergite extending slightly beyond the apex of the depression; legs fus- 

 cous; wings perfectly hyaline, the marginal fringe distinct; abdomen consider- 

 ably longer than, and one and one-half times as wide as, the thorax, ovate, 

 rounded apicall}^ Head of type male lost 1. aphidis Ashmead. 



4. Face just above insertion of antennae faintly transversely striate 5. 



Face just above insertion of antennae strongly transversly striate 6 



5. Notauli complete, well indicated 2. americana (Ashmead). 



Notauli not indicated anteriorly 3. floridensis Ashmead. 



6. Head narrower than the thorax; frons strongly elevated across the middle and 



with a broad and deep .longitudinal furrow reaching from the anterior ocellus 



to the striations below 4. obscuripennis Ashmead. 



Head never narrower than the thorax 7. 



7. Face just below anterior ocellus strongly granular with faint striae, the area just 



below this coarsely transversely striate 5. melliscapa (Ashmead). 



Face just below anterior ocellus not granular, either striate or shagreened; area 

 below this less coarsely striate 8. 



8. Upper part of face on sides shagreened 9. 



Upper part of face on sides striate ^ .. 11. 



