260 PROCEEDINGS OF THE ACADEMY OF [1897. 



12. Abdomen black, with cinereous pile ; third submarginal cell 



petiolate smaller than second ; middle segment strongly sul- 



cate down middle, sulcatus. 



Abdomen with first two segments red ; third submarginal not 

 petiolate, but greatly narrowed to marginal, somewhat larger 

 than second ; middle segment not sulcate, . . . fulgidifrons. 



13. Wings dark fuscous with purplish or aniline red effulgence; 



body entirely black, subopaque, rhomboideus. 



Wings subhyaline, or yellowish fasciate with fuscous, . . .14. 



14. Front not sericeous; wings with at least the portion between the 



dark fascia?, yellowish. Length 11-12 mm., . . . scrvpulus. 



Front covered with dense sericeous pile; wings hyaline between 



fascia?. Length 17 mm., serieeijrons. 



15. All claws bifid, 16. 



Anterior and middle claws bifid, posterior simple ; body dark, 



four hind coxa? red, rvficoxalis. 



16. Abdomen more or less red, : ... 17. 



Abdomen not red, 20. 



17. Wings dark fuscous ; first three segments red, 18. 



Wings subhyaline, darker apically ; abdomen entirely red, 19. 



18. Head in front not much longer than broad ; abdomen without 



cinereous pile, deceptus. 



Head in front much longer than broad ; abdominal segments four 

 and five with cinereous pile, angusticeps. 



19. Antenna? reddish; tarsal joints broadly ringed with white; 



third submarginal cell petiolate, annulipes. 



Antenna? black ; tarsi and four hind tibia? red ; third submar- 

 ginal not petiolate, personatus. 



20. Abdomen depressed, subsessile, 21. 



Abdomen more or less compressed, subpetiolate, clavate, . . 22. 



21. Posterior margin of pronotum and base of second dorsal abdom- 



inal segment, yellowish ; not maculated with pale pile ; wings 



subhyaline, darker along costa, insignitus. 



Not maculated with yellow, but the thorax and basal segments 

 of abdomen spotted with whitish pile ; wings dark, paler 

 medially, omamentus. 



22. Wings dark fuscous throughout, with blue or aniline red efful- 



gence; body dark, rhomboideus. 



Wings subhyaline, only in part fuscous, 23. 



23. Wings crossed by two heavy fascia? ; legs black ; base of seg- 



ments 1-3 whitish ; length 15 mm., scutellatus. 



