102 THE CANADIAN ENTOMOLOGIST. 



21. Clypeus subproduced, with a slight median sinus or incision anteriorly, 



the labrum well developed ; maxillary palpi 5-jointed ; labial palpi 



4-jointed. (Australia) Anthobosca, Guerin. 



(Type A. Australasise, Guer. 



22. Mandibles narrower, curved, the teeth acute ,; abdomen oblong, fusi- 



form or subcylindrical, as long or longer than the head and thora.x 

 united 23. 



Mandibles broad, the apical tooth large, obtuse, the inner tooth with 

 a long cutting face ; abdomen oval, hardly as long as the thorax or 

 no longer. 



Head about twice as wide as thick antero-posteriorly, not wider 

 than the thorax ; pronotum short, transverse ; mesonotum 

 fully as wide as long, with two furrows ; metathorax short, 



rounded behind Amblysoma, Weslw. 



(Type A. Latreillei, Westw.) 



23. First transverse cubitus with an appendage 24. 



First transverse cubitus without an appendage. 



Abdomen long, cylindrical, the first segment much longer than 

 wide at apex, petioliform. (South 



America) Klugianus, Ashm , gen. nov. 



(Type Thynnus haematodes, Klug.) 



24. Clypeus produced and anteriorly broadly truncate, trapezoidal .... 25. 

 Clypeus anteriorly not broadly truncate, slightly rounded, subemar- 



ginate, deeply triangularly emarginate, or bidenlate 26. 



25. Clypeus with a median carina; maxillary palpi 6-jointed, slender; 



labial palpi 4-jointed ; abdomen maculate or fasciate with 



yellow. (Australia) Zeleboria, Saussure. 



(Type Thynnus carinatus, Smith.) 



Clypeus without a median carina ; maxillary palpi 6-jointed, not 

 slender ; labial palpi 4-jointed ; abdomen with white spots, the 

 hypopygium near the tip with a pointed and a clavate appendage 



of hairs Psammothynnus, Ashm., gen. nov. 



(Type Thynnus depressus, Westw.) 



26. Hypopygium not prominently projecting, always obtuse or truncate at 



apex 27. 



Hypopygium much narrowed, narrowly rounded at apex, and 

 prominently projecting beyond the tip of the abdomen. 



