446 PROCEEDINGS OF THE NATIONAL MUSEUM vol. ii8 



7. Ninth tergum averages .12 mm. in length; marginal vein wider than post- 



marginal; median furrow of propodeum indicated in upper one-third to 



one-half 40. auriceps Walsh 



Ninth tergum averages .20 mm. in length; marginal and postmarginal linear 

 or about same width; median furrow complete to base. 



41. brevivena Bugbee 



8. Transverse carina on underside of front coxa produced into a tooth or short, 



blunt tubercle on outer margin 9 



Transverse carina on underside of front coxa not produced into a tooth on 

 outer margin; carina not sharp; bordering a very sliallow depression. . 10 



9. Proj^odeum irregularl}^, transversely striated medially; coarsely rugose 



laterally; abdomen not compressed, rather blunt at apex. 



42. obtusiventris Gahan 



Propodeum within excavation, nearly uniformly alveolately sculptured; 



abdomen compressed, acute at apex 43. vernonia, new species 



10. Sixth, seventh, and eighth terga densely clothed laterally with long, white 



hair, continues across dorsum of seventh and eighth terga; all terga finely 

 sculptiu-ed dorsally; face densely hairy; stigmal vein as long as marginal; 

 postmarginal much longer than marginal. . . . 44. bigeloviae Ashmead 

 Long, dense, white hair absent on terga; sixth tergum bare, others sparsely 

 hairy, laterally, but vestiture not long 11 



11. Pedicle, viewed dorsally, as long as the first funicle joint 12 



Pedicle distinctly shorter than the first funicle joint 14 



12. Propodeum broad and shaUowly concave to almost fiat; median furrow 



absent or indicated by wide-spaced lateral carinae in upper one-third to 

 one-half only; rest of surface irregularly ridged and pitted or finely 



punctate 13 



Propodeum rounded and narrowly concave with a deep and narrow median 

 furrow usually complete to base; head viewed dorsally, rounded anteriorly. 



45. atripes Gahan 



13. Small species averaging 1.6 mm. (1.3-1.9) in length; veins yellowish brown 



and linear; marginal averaging .20 mm. (.17-.25) and postmarginal aver- 

 aging .10 mm. (.07-.12); thus marginal averages twice the length of 



postmarginal 46. levivultus Bugbee 



Larger species averaging 3.3 mm. (2.7-3.7) in length; veins dark brown and 

 marginal wider than linear postmarginal; marginal only slightly longer 

 than postmarginal; marginal averaging .11 mm. and postmarginal .10 mm. 

 in length 47. tumoris Bugbee 



14. Antennal club distinctly a little thicker than the funicle 15 



Antennae filiform or without a distinct club 16 



15. Propodeum with a wide, complete median furrow that fills concavity of 



propodeum; lateral areas absent 48. fossae, new species 



Median fiuTow in upper one-half only or complete to base; lateral areas 

 distinct and finely punctate 49. tomici Ashmead 



16. Width of malar sj^ace less than half the eye height; sixth gastral tergum very 



weakly sculptured at lower angles only, otherwise it is smooth; interstices 

 between umbihcate punctiu-es of thorax unsculptured. 



50. appendigaster (Swederus) 



Width of malar space fully half as great as eye height (frequently longer) ; 



sculpture of sixth tergum usually more extensive; interstices often 



sculptiu-ed 17 



17. Abdomen plump; globular in lateral and dorsal view; indicating only slight 



lateral compression; ninth tergum short, broad, and stubby, averaging 



