'24:4: THE CANADIAN ENTOMOLOGIST. 



-bace medially Mi/A a well dehned, luiinded, saiuulh, shining swelling, 

 placed at an equal distance between the front ocellus and the base 

 of ihe antennye ; epicnemia of mesepisternum distinct ; front femora 

 in (^ without an emargination ; tarsal comb in 9 composed of very 

 long flexible bristles ; abdomen very coarsely punctured ; second 

 dorsal segment sharply margined at sides ; pygidial area in both 



sexes bare Prosopigastra, Costa. 



12. Pygidial area clothed with short, stiff bristles ; hind ocellar cicatrices 

 linear, hooklike; tarsal comb in $ with rather short spines; front 

 femora in ^ either simple or emarginate near base be- 

 neath Tachytes, Panzer. 



Pygidial area bare ; hind ocellar cicatrices oval ; tarsal comb in ? 

 with long, flexible spines Tachysphex, Kohl. 



Subfamily II. — Lyrodinae. 



In this subfamily the ocelli are always distinct, normal, never 

 aborted, the pronotum usually long, while the second cubital cell is 

 never petiolate or triangular. 



The distinct, ocelli easily separate the group from the Larrinse, while 

 the venation of the front wings and the longer pronotum separate it from 

 the Nitelinae and the Pisoninae. 



The known genera may be recognized with the aid of the following 

 table : 



Table of Genera. 



Marginal cell at apex truncate, or rarely rounded, but always 7ciif/i a 



more or less distinct appendage ; two or three cubital cells 2. 



Marginal cell lanceolate, ivithout an appendage ; three cubital cells. 

 Submedian cell shorter than the median, the second cubital cell 

 receiving both recurrent nervures, the second recurrent entering 

 it very close to the apex ; eyes convergent above ; mandibles not 



excised beneath Heliocausus, Kohl. 



Submedian cell a little longer than the median, the second cubital 

 cell receiving only one recurrent nervure at or near its middle, 

 the first recurrent nervure received by the first cubital cell near 

 its apex ; eyes only slightly convergent above ; mandibles deeply 

 excised beneath; cubitus in hind wings originating far beyond 



the transverse median nervure Zoyphium, Kohl. 



2. Front wings with two cubital cells 4. 



Front wings with three cubital cells. 



