BY THOMAS G. SLOANE. 125 



Genus C A r e n i d i u m. 



Chaudoir, Ann. Soc. Ent. Belg. 18G9, p. 149; Cono-pterura {gen. 

 ined.), Chaudoir, I.e. p. 148. 



The genus Carenidium may be differentiated from the other 

 Carenid genera by the following features in combination : — 



Palpi with apical joint very widely securiform; labial with 

 penultimate joint short, plurisetose in front ; the suborbital 

 antennal scrobes deep, narrow, bordering and following the con- 

 tour of the paragense, their upper margin forming a more or less 

 distinct ridge; antennae setaceous; elytra with lateral border 

 narrow and neither thickened nor upturned in a projection at 

 the humeral angles; apical ventral segment with upturned edge 

 foveate on each side of apex. 



I do not think Conopterum, which has the labrum and clypeus 

 truncate, can be separated as a genus distinct from Carenidium. 

 G. septentrionale, MacL, with the clypeus as in C. riverince, Mack, 

 but the wide labrum lightly emarginate (also mandibles in Q 

 intermediate in form between those of C. gagatinum, Mack, and 

 C. riverince, Macl); and C. sapphirin^im, Bates, with both clypeus 

 and labrum only lightly emarginate, are species which seem to 

 compel the union of Conopterum with Carenidium. 



Table of Species. 



I. Labrum and median part of clypeus emarginate; mandibles when closed 



not forming a raised ridge before labrum (Carenidium, typical form). 



A. Elytra not mucronate at apex. 



B. Head strongly narrowed on each side behind eyes; infiexed margins 



of elytra wide, strongly and continuously narrowed to apex. 



c. Elytra impunctate. 



d. Punctures on base of elytra not placed in a depression. 



e. Prothorax subparallel on sides between marginal punctures; 



colour black C. gagatinum, Mack 



ee. Prothorax cordate, sides rounded; upper \ 



surface with metallic tints (violaceous) l^" ^upe'-bum, Cast. 



^ \ U. pyripemie, hi. 



at least near margins J 



dd. Punctures on base of elytra placed \ 



1 T 1 • J • /TT I C. sapphiriinim, Kates, 



obliquely in a depression. (Upper V^ Jj^ingi, Mack 



surface green, at least near sides).. ) 



