THE CANADIAN ENTOMOLOGIST. 309 



Mandibles bidentate ; first juint of 

 the flagellutn long, fully as 

 long as 2nd and 3rd 

 united. .? Tetraphotopsis, Ashm. 



Mandibles acuminate, decussate, 



without teeth ; first joint of the 



flagellum obconical, longer than 



the second. .PNeophotopsis, Ashm. 



Left mandibles without an incision beneath, 



simple ? genus. 



24. Thorax banjo-shaped, or nearly, much contracted at the sides. . . .32. 

 Thorax obpyriform, obovoid or obtrapezoidal 25. 



25. Mandibles beneath simple, not excised 26. 



Mandibles beneath, or at least the left mandible, excised and usually 



with a process or projection before the incision .... 28. 



26. Mandibles at apex 3-dentate 27. 



Mandibles at apex simple or at most with a small tooth within before 



apex, or bidentate. 



Head rather large quadrate or subquadrate, the temples 

 broad Nomiaephagus, Ashmead. 



27. Head subglobose, the temples not especially broad, the antennal 



fovese not deep, without a carina superiorly. . .Brusia, Ashmead. 



28. Pygidium smooth, without a pygidial area ; eyes short, 



oval Tricholabiodes, Radoszkowski. 



Pygidium not smooth, with a pygidial area. 



Body bare or nearly, at the most clothed with a sparse 

 pubescence. 



Mandibles edentate, pointed at apex ; first joint of the 

 flagellum not, or scarcely, longer than wide, and 

 very little longer than the second. Photopsis, Blake. 

 Body clothed with a dense pubescence. 



Mandibles acuminate, but with a slight tooth within before 

 apex Pyrrhomutilla, Ashmead. 



29. Thorax coarsely, rugosely punctate, pitted or foveolated, the front 



margin truncate, the angles acute or toothed, the lateral margins 

 with a prominent tooth at the beginning of the contracted 



portion or in the tegular region 30. 



Thorax not coarsely, rugosely punctate or pitted, although punctate, 

 the front angles rounded, the lateral margins without a tooth, 31. 



