302 TRANS. ST. LOUIS ACAD. SCIENCE. 



Prothorax twice as wide as long, sides with three 

 recurved spines, elytra with one discal line, an- 

 tennte geniculate - - - - Rhexius Le Conte 



d' Body depressed, antennie thicker towards the apex. 



f" Tarsi with a single claw, antennal club 3-jointed. 

 Vertex arcuately impressed, not produced in front. 

 Body broader, lateral margin of the pronotum cre- 

 nate, prosternum carinate, fourth dorsal segment 

 not prolonged ----- Thesium Casey 



Body slender, pronotum with lateral longitudinal 

 grooves, prosternum carinate, fourth dorsal not 

 prolonged ------ Faliscus Casey 



Body linear, lateral margin of the pronotum sim- 

 ple, the fourth dorsal segment prolongate 



EuPLECTUS Leach 



f Tarsi with two equal claws. Body linear, anten- 

 nal joints gradually slightly larger towards the 

 apex {Sagola Sharp, Sonoma Casey) - Fakonus Aube 



