G8 Bulletin Wisconsin Natural History Society. [Vol. 8. No. 2. 



6. Abdomen entirely black, scutellum indicated as short and 



broad P.obesus. 



Abdomen yellowish on the tips of the first and second seg- 

 ments; seutellnni indicated as a small convex tubercle P.habilis. 



7. Male, antennae 21-jointed, abdominal hairs sparsely placed. 



P.foveatus. 



Females 8. 



8. Hairs of abdomen sparsely placed ; scutellum not at all indi- 

 cated P.insolens. 



Hairs of abdomen densely placed; scutellum indicated by a 

 distinct grooved line basally P.delumbis. 



Pezomachus cockerelli sp. nov. 

 Female. Length 4 mm. Piceous black ; base of antennae, anterior 

 part of prothorax and tip of first abdominal segment brownish yellow. 

 Legs very dark fuscous. Head above shining, very faintly shagreened ; 

 slightly less than half as thick as broad ; the occiput feebly excavated. 

 Ocelli in an equilateral triangle, closer to each other than to the eye 

 margin. Front almost twice as wide as either eye, with a broad, shal- 

 low depression above the base of the antenna?. Seen from the side, 

 the head is much produced into a ledge at the insertion of the antennas. 

 Malar line long, although but little more than half as long as the broad 

 front. Upper edge of clypeus far below the lower corner of the eye 

 which is equidistant from the vertex and lower corner of the cheek. 

 Clypeus moderately convex with a fovea at each side. Thorax long, 

 three and one-half times as long as broad. Meso- and metanotum 

 shining and scarcely shagreened. Metathorax evenly convex, without 

 any transverse carina although this is indicated on the sides by a 

 slightly raised line. Petiole of abdomen rather long and broad at the 

 tip which is nearly three times as broad as the base ; its length equal 

 to twice its greatest width; spiracular tubercles slightly projecting; 

 spiracular carina obsolete before the spiracle, visible only behind it 

 halfway to the apex of the petiole. Abdomen broad, fully twice as wide 

 as the thorax ; smooth and shining ; its pale hairs densely placed. 

 Second segment the longest ; others gradually decreasing in length. 

 Ovipositor only two thirds as long as the petiole. Pleura? regularly 

 shagreened and subshining. Legs stout, the longer spur of the hind 

 tibia one-third as long as the metatarsus which is twice as long as the 

 second tarsal joint. 



Florissant, Colorado, July 8, 1906. Collected by Professor 

 T. D. A. Cockerell. 



