NORTH AMERICAN COLEOPTERA. 



3 



Mentum oval, longer tlian wide, apex arcuate, base emarginate, 

 supported by a broad peduncle of the subnientum, the free fiice 

 roughly punctured, with long hairs. 



LiGULA free, arising behind the apex of the mentum, corneous, 

 form short and transverse, slightly emarginate. 



Labial palpi as long or even longer than the mentum and ligula, 

 arising from the apex of the ligula, three-jointed, the last joint as 

 long as the two preceding and more slender. 

 ■ Prothorax transverse, the sides broadly arcuate. 

 ScuTELLUM transversely oval. 



Elytra longer than wide conjointly, the apices obtuse ; disc with 

 a sutural costa, three oblique discal costse, limited usually faintly, by 

 geminate stripe, a feeble submarginal costa. 



Anterior oox.e large, conical and prominent, with a large tro- 

 chantin. 



Middle cox.e large, very narrowly separated. 

 Posterior cox.e transverse as usual, rather short, contiguous at 

 middle, but not prominent. 



Metasternal episterna narrow, the epimeron distinct. 

 Abdomen with six segments, all freely movable, the first concealed 



by the coxse and broadly membranous 

 at middle, segments nearly equal in 

 length. By dissection an anal segment 

 is observed, which is always closely 

 retracted. Dorsal portion of abdomen 

 consists of eight semi-membranous seg- 

 ments. 



Abdominal spiracles, seven on 

 each side, are situated in the connecting 

 membrane which unites the dorsal and 

 venti'al [)lates. 



Anterior tible with three large 

 teeth occupying the apical half of the 

 outer edge ; four or five smaller teeth above. 



Middle tibi^ broader at apex, tlie apical margin undulated or 

 subdigitate, a strong transverse carina at middle of outer edge. 



Posterior tibiae similar in form, the apex, however, less undu- 

 lated. 



Tarsi slender, as long as the tibiie, the first four joints slightly 

 decreasing in length, last joint as long as the three preceding. Ony- 

 chium distinct, trisetose at apex. 



