BY WILLIAM MACLEAY, F.L.S., &C. 117 



and not very definite, bat that I find unavoidable, as there are very- 

 few marked distinguishing features in the group, and even these 

 run into One another in the most puzzling manner. 



Group, Carenides. 



Mentum large, flat, carinated in the middle, the median tooth 

 very strong. 



Labium cut squarely in front, the paraglossaj slightly passing it. 



Palpi more or less securiform. 



Maxillce straight, rounded at the apex. 



Mandibles strongly toothed on the internal side. 



Labrum short. 



Antennce short, compresssed, moniliform or filiform. 



Thorax and elytra of variable form. 



Anterior tibice strongly palmate and toothed externally. 



Tarsi simple in both sexes. 



Bod'i/ apterous. 



This group I propose to distribute into the following genera : — 



Monocentrum, Teratidlum, Carenidium, Conopterum, Neoca- 

 renuin, Eutoma, CarenoscajjJms, Carenum, Calliscapterus, Platy- 

 tliorax, Laccojiterum, Philosca2)hics, Etoryscaphus, and Scaraphites. 



Genus, Monocentrum, Chaud. 



Of very narrow elongate form. Head large, antennae short, 

 robust, compressed, submoniliform ; labial palpi securiform. 

 Frontal canals deep, diverging behind. Thoi'ax much longer than 

 broad. Elytra narrow, cylindrical. Anterior tibife unidentate 

 externally. Ventral segments impunctate. 



Three species have been assigned to this genus, all from 

 Northern Queensland. M. megacephalum (Carenum megacep>halum) 

 Westwood, M. grandiceps, Chaud. and 31. longiceps, Chaud. I 

 have one specimen of the grandiceps from the Dawson River, the 

 only one of the genus I have seen. 



