220 GEO. H. HORN, M. D. 



Eyes oval or round, entire, usually finely granulated, coarsely in 

 some Clambini. 



Antenna variable in insertion, sometimes free at base (some 

 Silphini and Cholevini), or under a frontal margin (Anisotomini), 

 usually arising close to the eyes or distant from them (some SUphse 

 and in Empelits and Calyptomerufi) ; usually eleven-jointed, rarely 

 ten- or nine-jointed, the terminal joints either forming a club of 

 variable structure, or gradually broader, rarely nearly filiform {Ptero- 

 loma and Apatettca). 



Prothorax without distinct side pieces. 



Mesosternum short, side pieces closing the coxal cavities ex- 

 ternally. 



Metasternum usually large, truncate behind, short in the genera 

 without eyes, side pieces distinct, the episterna long, epimera distinct, 

 but in the Anisotomini partly concealed by the elytra. 



Abdomen usually with six segments (seven in Empelua), rarely 

 with five {iSphserites, Li/rosoma, Colon, Clambus), or even four (many 

 females of Colon). 



Anterior cox^e contiguous, conical, transverse at base and with 

 trochantin, cylindric-conic and without trochantin in Cholevini ; the 

 coxal cavities strongly augulate externally (except Cholevini), and 

 open behind in the first three tribes, closed in the others. 



Middle coxje not prominent, usually separated, rarely contiguous, 

 oblique or transverse {Clanibus and CaJijptomerus), with distinct 

 trochantin, the cavities closed externally by the mesosternal side 

 pieces. 



Posterior cox^ transverse, sometimes prominent internally (some 

 Silphini), and in Clambini laminate, the plates more or less concealing 

 the posterior legs. 



Legs often stout and fossorial or very slender; tibiae usually with 

 prominent terminal spurs which are rarely absent. 



Tarsi usually five-jointed, variable sexually or generically (Aniso- 

 tomini, Cholevini), or four-jointed (Clambini). 



Elytra usually entire, covering the abdomen, sometimes truncate 

 {Nec7'ophorus, some Silpha, Sphserites and Ap>atetica), epipleurse 

 distinct except in Clamhus and Calyptomerus. 



The above characters define, as far as it is possible in a general 

 manner the present family, and the scheme seems principally note- 

 worthy from the number of the exceptional cases, notwithstanding 



