NORTH AMERICAN TETRASTTCHUS BURKS 515 



50. Malar furrow curved and forming, with ocular suture, a triangle at ventral 



margin of compound eye (fig. 16, c), length of malar space two-thirds as 



great as height of compound eye pattersonae Pullaway (p. 563) 



Malar furrow straight (fig. 16, &) ; length of malar space one-half as great 

 as height of compound eye 51 



51. Antennal club short, ovate, less than twice as long as second funicle segment; 



body usually bright, iridescent green, with femora entirely light yellow or 

 white ; forewing of male with a conspicuous patch of dark setae on anterior 



margin near apex spilopteris, new species (p. 564) 



Antennal club almost three times as long as second funicle segment ; body 

 usually entirely very dark brown, almost black, occasionally with faint 

 iridescent reflections, femora always partly brown ; forewing of male with- 

 out a patch of dark setae verrucarii Balduf (p. 565) 



52. Body varying from very dark brown to black, and with only very faint 



iridescent blue or blue-green reflections; submarginal vein of forewing with 

 two dorsal bristles; mesoscutellum often bearing three pairs of bristles; 

 propodeal spiracles round, paraspiracular carinae faint, posterior end reach- 

 ing postspiracular suture, as in fig. 21, h; postscutellum smooth. 



carpatus, new species (p. 566) 

 Not having that combination of characters; propodeum either lacking para- 

 spiracular carinae, or these carinae present and posterior end reaching 

 posterior margin of propodeum 53 



53. Marginal vein of forewing three or more times as long as stigmal vein 54 



Marginal vein of forewing twice as long as stigmal vein 55 



54. Surface of propodeum shagreened, paraspiracular carinae present, median 



carina well developed hunteri Crawford (p. 567) 



Surface of propodeum smooth, paraspiracular carinae wanting, median carina 

 only vaguely indicated turionum (Hartig) (p. 56S) 



55. Metatibiae partly dark brown caerulescens Ashmead (p. 568) 



Metatibiae entirely light yellow or white dolosus Gahan (p. 570) 



56. Setae laterad and ventrad of scrobe cavity set in deep pits; ocellar triangle 



with large, deep punctures (fig. 17, c) ; a triangular fracture present at 

 ventral margin of each compound eye (this fracture very small in one 



species) 57 



Setae on face not set in deep pits; ocellar triangle not with large, deep pits; 

 triangular fracture not present at ventral margin of each compound eye_ 60 

 67. Paraspiracular carinae absent, surface of propodeum shining and with very 

 shallow, obscure reticulations ; prepectus faintly reticulated. 



strobilus, new species (p. 570) 



Paraspiracular carinae present, surface of propodeum strongly sculptured ; 



prepectus deeply punctured or strongly reticulated 58 



58. Rudimentary petiole with dorsal surface smooth, as in fig. 21, e; propodeum 



with shallow reticulate sculpturing sobrius Gahan (p. 572) 



Rudimentary petiole with dorsal surface distinctly sculptured, as in fig. 21, h; 

 propodeum closely and deeply punctured 59 



59. Thorax dirk, iridescent blue-green with occasional purplish reflections ; median 



groove of mesopraescutum relatively broad; propodeum with median and 



paraspiracular carinae, fig. 21, & punctatifrons (Girault) (p. 572) 



Thorax dark, shining brown or black, noniridescent ; median groove of meso- 

 praescutum fine: propodeum with median, paraspiracular, and oblique 

 carinae, as in fig. 21, d banksii Howard (p. 573) 



60. LApex of hindwing acute, as in fig. 20, f, h; fringe at posterior margin one-half or 



more as wide as wing at hamuli 61 



