202 ENTOMOIX)GICAL NEWS. [May, '15 



Table of Species. 



1. Posterior cross vein oblique, more or less sinuate 2 



Posterior cross vein perpendicular to fourth and fifth veins, 



straight 5 



2. First antenna! joint nearly four times the length of second; ro- 



bust, mostly shining species setosa 



First joint at most twice the length of second; mostly opake 

 species 3 



3. Face pilose; small c. v. at or beyond middle of discal cell. 



Abdomen opake trochilus 



Abdomen shining black, margins of segments yel- 

 low cinctura 



Face bare; small c. v. far before middle of discal cell 4 



4. Large (6.0 mm.) robust species capax 



Small (3.5 mm.) slender species sigma 



5. Males 6 



Females 11 



6. Shining black, at most faintly pruinose below atra 



Mostly cinereous species 7 



7. Mesonotum with distinct broad black vittae mitis 



Mesonotum cinereous, at most narrowly bivittate or faintly 



marked 8 



8. Third antennal joint broadest before its middle and some- 



what tapering apically, tibiae mostly yellow fasciola 



Third antennal joint broadest beyond its middle, not tapering 

 apically, tibiae black 9 



9. Mesonotum densely cinereous, narrowly bivittate with black, 



with faint sublateral presutural spots bivittata 



Mesonotum at most faintly marked 10 



10. Larger (3 mm.), robust, pilose species knabi 



Small (2 mm.), slender, nearly bare species obscura 



11. First antennal joint, anterior half of frons, humeri and 



scutellum yellow knabi 



These parts black, more or less densely cinereous 12 



12. Mesonotum distinctly broadly trivittate with brown; orbits 



of frons and face yellow f ormosa 



Mesonotum narrowly bivittate and with large sublateral spots, 



subopake, black mitis 



Mesonotum indistinctly marked or narrowly bivittate 13 



13. Mesonotum densely cinereous with median pair of narrow 



vittae and faint sublateral presutural spot (compare fasciola) 



bivittata 

 Mesonotum not or faintly trivittate 14 



