6 1 8 COLEOPTERA 



hollowed. Labrum always distinct, transversal, attenuated ; its lateral 

 margins rounded; the anterior margin thickened, straight, or emarginate. 

 Mandibles moderate, rarely very prominent, sub-trigonal ; their external 

 face convex, the internal concave ; extremity rather broad, and more 

 or less dentate. Maxillce with two unarmed lobes, ciliated ; the inner 

 the shorter and wider; the external elongate, slender, almost bi-articulate ; 

 palpi filiform, four-jointed ; the first short, second and third slightly 

 obconical ; the fourth elongate or equal to the preceding, attenuated 

 towards the apex, not truncated, sometimes obtuse, occasionally 

 acute. Under-lip indistinct. Mentiim transversal, rounded or hollowed 

 anteriorly. Ligula small, corneous, emarginate at its free edge ; with 

 tri-articulate feelers, the first joint short, second and third long, 

 sub-equal, of the same form as the maxillary. Eyes rather large, 

 slightly convex, reniform, emarginated inwardly ; the hollow more or 

 le'ss profound, triangular, or like the segment of a circle ; they are very 

 rarely rounded, nearly entire, or simply sinuated inwardly. AntenncE 

 distant from each other, inserted near the lower part of the inner 

 margin of the eyes ; formed of eleven joints, with a more or less 

 perceptible false joint of variable length ; sometimes slender, filiform, 

 sub-clavate, sometimes with the terminal joints dilated and forming an 

 elongate club sub-dentate inwardly. Prothorax invariably transversal, 

 more or less convex, sometimes bulging on its discoidal part, the sides 

 strongly inflexed towards the anterior angles ; anterior margin sub- 

 truncate ; sides straight, sub-rounded, or oblique ; the base often 

 denticulate, emarginate or bi-sinuate ; with a median lobe, sometimes 

 very large, sometimes nearly obsolete, entire, rounded or truncated, 

 bifid or dentate ; the posterior angles sometimes acute, prolonged, and 

 more or less embracing the base of the elytra, sometimes straight or 

 obtuse. Scutclluin visible, very rarely indistinct, plane or elevated 

 towards the summit, sometimes nearly vertical ; of extremely variable 

 form. Elytra oblong, sub-cylindrical, shorter than the body, their 

 lateral margins parallel or converging posteriorly ; shoulders more or 

 less prominent ; their surface irregularly punctate, or punctured in rows. 

 Prosternuni always much developed, and separating, more or less, the 

 front coxfe ; episterna rather large, triangular, touchmg the front angles 

 of the pronotum ; epimera indistinct, prolonged from the coxse, and 

 closing the cotyloid cavities. Mesosterniim transverse or oblong. 

 Metasternum longer than the pro- and meso-sterna united ; its episterna 

 confounded with the epimera and forming a rather large lamelle. 

 Abdometi with five segments, the first and fifth most developed, the 

 intermediate narrowed in the middle ; the third and fourth sometimes 

 soldered to the last, with their sutures more or less obliterated ; the 

 pygidium always more or less exposed. Legs moderate, the front and 

 intermediate moderately and equally distant from the median line ; 

 the posterior a little more remote, one from the other. Coxce of the 

 four front legs sub-globose, the posterior a little transversal. Femora 

 slightly swollen in the middle, the anterior sometimes much developed. 

 Tibicz slender, straight, or slightly arcuated at the base, sometimes 

 almost dilated towards their extremity. Tarsi presenting few modifi- 

 cations ; their claws simple or appendiculate. 



