IGO PROCEEDINGS OF THE ACADEMY OF 



wings, flanks of metathorax, broad arcuated line on posterior face 

 covering spines, coxae, posterior tarsi except base and apex, and 

 apical margins of all the abdominal segments, white or soiled 

 white; wings hyaline, iridescent ; legs pale honey-yellow, stripe 

 on posterior coxae, four anterior tarsi and apex of posterior tibiae, 

 black or fuscous. Metathorax deeply excavate behind, the 

 upper edge carinate and produced on each side into an obtuse 

 tubercle; areolet minute, open; sutures of thorax crenulated, 

 middle lobe of mesothorax witli a crenulated central impressed 

 line ; antennae long and ver3^ slender. Length 4 lines. 

 Orizaba. (Sumichrast, No. 01.) 



20. Mesostenus abactus, n. sp. 



9. Black; face, mouth, orbits, scape beneath, broad annulus 

 on flagellum, collar, tegulae, line before, central stripe on meso- 

 thorax, scutellum, line on each side before, band behind dilated 

 behind base of wings, flanks of metathorax, two elongate marks 

 on posterior face covering tubercles, pleura except an oblique lino 

 beneath wings, coxre except stripe on outside of posterior pair and 

 their base within, base of fust and rather broad apical margin of 

 all the segments, white; wings hyaline; legs pale hone3'-yellow, 

 tips of all the tarsi black, the posterior pair yellow. Opaque, 

 middle lobe of mesothorax finely aciculated transversely* ; meta- 

 thorax rugose, tubercles transverse, verj' blunt ; areolet very 

 minute, open. Length 4 lines. 



Mirador. 



21. Mesostenus admonitus, n. .p. 



%, Black; face, mouth, narrow orbits, annulus on antennae, 

 teguhxi, spot in front, another beneath, scutellum except base, spot 

 on postsculellum, space behind base of wings, spot on each flank 

 of metathorax, two elongate marks on i)ostcrior face covering 

 spines, four anterior coxae and trochanters, large spot on posterior 

 coxic above, tarsi except tips, base of first abdominal segment 

 and apical margin of all the segments, dilated laterally', white or 

 yellowish-white; wings hyaline, nervures black; femora and tibiae 

 pale honey-yellow, the posterior femora black at base and apex. 

 Head and thorax robust, abdomen slender; mesothorax dcn.sely 

 rugose ; metathorax rugose, posterior face coarsely reticulated, 

 tubercles flat and obtuse; upper anterior angles of prothorax very 



