406 COLEOPTERA OF NORTH AMERICA. 



rklge in front of the eyes, 11-jointed; slightly thickened 

 towards the tip. 



Prothorax elongate, trapezoidal, as wide at base as the 

 elytra, lateral suture wanting; coxal cavities large, confluent, 

 open behind. 



Mesosternam acute; side pieces reaching the coxal cavi- 

 ties, which are confluent ; nietasternum long, side pieces 

 narrow. 



Elytra gradually narrowed from the base, as long as the 

 abdomen ; epipleurse narrow but distinct, not extending to 

 the tip. 



Abdomen with six free ventral segments, the 6th short, 

 deeply emarginate in the male, permitting the 7th to be seen. 



Legs long and slender; anterior and middle cox» large, 

 conical, contiguous, with distinct trochantins ; hind coxie 

 slightly oblique, prominent, concave behind near the tip ; 

 tibial spurs long, slender; tarsi filiform, pubescent beneath; 

 claws pectinate, each with a large appendage, as long as the 

 claw itself, and obtusely rounded at the tip. 



The characters above given are sufficient to show that the genus 

 Cephiiloon should rank as a distinct family. It was placed by 

 Newman, who first described it in ffidenieridse, by Dr. Le Conte 

 in MeloidiE, and more recently by Motschult^ky in M e I an dry i die. 

 None of these positions will, probably, be found correct. From 

 the Meloidse it differs by the thora.x being as broad at base as 

 the elytra, as well as by the different form of the head. From 

 Melandryidae it differs not only by the head being constricted at 

 base, but by the lateral suture of the prothorax being wanting, 

 and by the greater number of ventral segments. Its resemblance 

 to ffidemerida5 is more decided, though from them it is at once 

 distinguished by the head being constricted at base, as well as by 

 the peculiar form of the claws. 



Two specijes of Cephaloon occur in the northern part of the 

 Atlantic region, and a third one in Washington Territory; 

 species are also found in Siberia, in the Amur district. 



Fam. LXYIIL— mordellidae. 



Mentum trapezoidal, supported by a gular process; ligula 



prominent, cordiform ; palpi 3-jointed, last joint triangular. 



Maxillas with large, prominent base, and two ciliated 



