NATURAL SCIENCES OF PHILADELPHIA. 149 



Subgenus PolytEnus. 



This subgenus is formed for the reception of two species differ- 

 ing from Polycyrtus in having tioo short nearly contiguous spines 

 on the front. The form is also shorter and more robust, the 

 regions of the mesothorax not at all prominent, and the first ab- 

 dominal segment rather short and broadly though gradually 

 dilated at apex. The areolet of anterior wing is elongate, narrow, 

 and closed. 



1. Polyaenus ectypus, n. sp. 



9. -Black; face, mouth, orbits, collar, tegulne, spot before, an- 

 other beneath, apex of scutellum, two oblique lines in front, post- 

 scutelhim, pleura except anterior margin, raetathorax except a 

 broad central stripe crossed near base by a slender line to spira- 

 cles, legs, base of first abdominal segment, broad apical and lateral 

 margins of all the segments, and basal corners of second segment, 

 yellowish-white; broad annulus on antennae pure white; wings 

 hyaline ; trochanters, femora above and tarsal tips dusk3% Slender, 

 shining; frontal spines short, acute; upper lateral angles of pro- 

 thorax prominent, tuberculiform ; metathorax longitudinally 

 rugose down the middle, the spines prominent, obtuse ; abdomen 

 polished ; areolet small, narrow, closed. Length 5 lines. 



Orizaba. 



2. Polyaenus ablatus, n. sp. 



9. Black; face, mouth, orbits broadly interrupted behind, 

 tegulffi, spot in front, dot beneath, apex of scutellum, two oblique 

 lines in front, postscutellum, space behind base of wings, flanks 

 of metathorax, two elongate marks on its posterior face covering 

 spines, broad oblique mark on each side of pleura, most of legs, 

 base of first abdominal segment, broad apical and narrow lateral 

 margins of all the segments, and basal corners f second segment, 

 yellowish white; broad annulus near apex of antennoe pure white; 

 wings hyaline ; all the coxte within, four anterior ti'ochanters be- 

 neath, the posterior pair except base above, four anterior femora 

 beneath, tips of their tai'si, and posterior femora, except two 

 broad yellow stripes one outwardly and the other above, black ; 

 posterior tWnx bright yellow. Head and thorax robust, densely 

 and confluently punctured, pubescent ; frontal spines sliort, acute ; 

 upper lateral margins of prothorax not so prominent as in ectypus; 



