268 AMERICAN HYMEXOPTERA. 



44. INFetanotum without areolets 45. 



Metanotum more or less areolated 49. 



45. Lower tooth of mandibles much longer tlian upper ''AzeliiN Foer. 



Lower tooth of mandibles not longer than upper 46. 



46. Humeral cross-nervure broken at or a little above (seldom a little below) the 



middle 47- 



Humeral cross-nervure broken plainly below the middle. ."•■■Adranes Foer. 



47. Segment 4 plainly shorter than the third 48. 



Segment 4 fully as long as 3 - Zaplittiora Foer. 



48. Clypeus flat, slightly rounded at apex, nearly truncate and without elevated 



front margin ; segments 2 and 3 without an arched side ledge. 



Adexioina Foer. 



Clypeus transversely impressed before apex and with median and lateral 



apical emarginations ; segment 2 with distinct arched ledge at side: 



spiracles not close to lateral margin Lamaelius Foer. 



49. Metanotum entirely areolated 50. 



Metanotum not entirely areolated 52. 



50. Last member of hind tarsi not (?) longer than third. 



■XrophoctonuM Foer. 

 Last member of hind tarsi not (?) longer than third 51. 



51. Clypeus with transverse impression before apex ■■■■Syiiomelix Foer. 



Clypeus without transverse impression before apex- •^-Oastroporiis Foer. 



52. Clypeus compressed and drawn forward to a more or less distinct tooth. 



■■Paiilorhaestes Foer. 

 Clypeus not compressed so that the middle projects tootli-like 53. 



53. Clypeus forming a flat triangle whose broadest side is the front edge. 



''Zapeflias Foer. 

 Clypeus not forming a flat triangle 54. 



54. Segment 1 with two keel-like carinse which extend beyond the spiracles. 



I>ialge>$ Foer. 

 Segment 1 without carinte, or they do not extend beyond the spiracles. . • .55. 



55. Front with a median furrow; second and following segments are smooth. 



'Zeiniophroii Foer. 



Front without median furrow; second and following segments not all 



smooth 56. 



56. Clypeus transversely impressed before apex so that the front edge appears 



elevated ' 57. 



Clypeus without transverse impression before the apex, and therefore the 

 front edge has no margin 58. 



57. Stigma very small, radius starting from basal third ; base of discoidal cell 



fully twice as broad as the transverse median nervure. 



'-''Oiieista Foer. 



Stigma rather small, radius starting from or somewhat in front of the middle 



(never from basal third); base of discoidal not twice as broad as the 



transverse median nervure •■•Bysantes Foer. 



58. Middle of face and clypeus arched ; the front with more or less of a shield- 



like elevation NteillOU Foer. 



Middle of face and clypeus not arched ; second abdominal segment quad- 

 ratic 59. 



