668 REVISION OF THE GENUS HETERONYX, 



more than half as wide as the 

 lateral lobes 



E. Prothorax feebly (at most) lobed 

 hindward • • • . . , 



F. Prothorax considerably narrowed 

 in front ; elytra set with numer- 

 ous long erect hairs among the 

 adpressed pubescence vagans, Blackb. 



FF. Prothorax very little narrowed 

 in front ; elytra not set with 

 numerous long erect hairs ... mimus, Blackb. 



EE. Prothorax very strongly lobed 

 hindward, — not much less 

 strongly than in H. lobatus, 

 Blackb castaneus, M.Sicl. 



H. DIMIDIATUS, Er. 



I do not think that I have seen an example of this insect, 

 which is said to occur in Tasmania, and is probably limited to 

 that island. The following five species are all closely allied to it 

 in having the anterior half or thereabouts of the upper surface 

 clothed with long erect hairs, the head and prothorax ordinarily 

 black or pitchy and the elytra usually ferruginous with more or 

 less dark colouring in front, and the elevation of the labrum 

 above the clypeus usually very slight. The greater part of Erich- 

 son's description would apply to nearly all the species known to 

 me of this group, but it mentions one character which seems to 

 difierentiate dhnidiatus strongly, viz., "fronte parce subtiliter 

 punctata," as contrasted with "clypeo punctato-rugoso." No 

 species that I have seen in the group shows any indication of this 

 sculpture. As Erichson gives no exact description of the claws 

 or of the relative length of the hind coxae and metasternum it is 

 of course not certain that H. dimidiatus would fall in this group 



