192 HYMENOPTERA. 



A. Areolet triangular, or, at least, with the lateral nermres distinctly converging 

 above ; abdomen longitudinally striated*. 



Synopsis of the Species. 



1 (9). Mesonotum without black. 



2 (8). Wings hyaline, black at base. MaPf 



3 (4). Head entirely black melanocephala, 



4 (3) . Head only black above. 



5 (6). Hind coxae entirely yellow, base of second abdominal segment not 



black, extreme apex of hind femora only black varipes. 



6 (7) . Hind coxae entirely black ; metanotum smooth, impunctate ; abdo- 



men longitudinally striated variolosa. 



7 (6). Hind coxae yellow, with two black spots ; abdomen longitudinally 



aciculate, metathorax longitudinally striated elegantula. 



8 (2) . Wings entirely black . fumipennis. 



9 (1) . Mesonotum marked with black. 



10 (11). Wings entirely yellow alternans. 



11 (12). Wings yellowish, a small fascia at base of radial cellule; metathorax 



with two short spines behind ; petiole black suturalis. 



12 (15). Wings yellowish, the apex smoky. 



13 (14) . Apex of tibiae and stigma black melanostigma* 



14 (13). Apex of tibiae and stigma yellow xanthostigma. 



15 (22). Wings yellowish, the base and apex black. 



16 (19). Pleurae entirely yellow. 



17(18). Scutellum and base of metathorax black decorata. 



18 (17). Scutellum and base of metathorax yellow incerta. 



19 (16). Mesopleurae black. 



20(21). Apex of hind femora black, apex of tibiae yellow maculicomis* 



21(20). Apex of hind femora yellow, tibiae broadly black hilaris. 



22 (27). Wings violaceous, the middle more or less hyaline. 



23 (26) . Pro- and mesothorax and head black, femora broadly black. 



24 (25). Scutellum flat in centre, third abdominal segment shorter than all 



the following together rogersi. 



25 (24) . Scutellum sharply peaked, third abdominal segment almost longer 



than all the succeeding together nigriceps. 



26 (23). Pronotum and pleurae yellow, hind knees only black modesta. 



27 (22). Wings hyaline, apex and one or two fasciae in the middle black. 



28 (33) . Mesonotum entirely black. 



29 (30). Pleurae entirely yellow, hind knees only black chiriquensis. 



* Brulle (Hymen, iv. pp. 270 & 287) divides the genus into two divisions, but he gives the same distinctive- 

 characteristic to both, namely, the possession of a pentagonal areolet. His first section has certainly the 

 areolet pentagonal ; but I cannot make out if his second group has it 4-angled, as he does not mention its 

 form in any of the species, other than in the (probably erroneous) sectional heading on p. 287. 



