434 REVISION OP THE GENUS HETERONYX, 



potens), their inner apical angle scarcely defined. The three 

 external teeth of the anterior tibiae are fairly strong, the upper- 

 most about half as large as the intermediate one. The apical 

 piece of the hind claws is about a quarter the size of the basal 

 and scarcely twice as large as the produced apex of the latter. 

 The bifid apex of the claws is much more minute than in //. 

 2ootens. 



Basin of Lake Eyre. 



H. BIDENTATUS, Sp.nOV. 



Sat elongatus ; postice vix dilatatus ; minus nitidus ; fusco- 

 testaceus ; pilis adpressis minus brevibus sat dense vestitus ; 

 capite pygidioque (his pilis erectis plus minus vestitis) sparsius 

 subtilius, prothorace elytrisque crebre subtiliter, punctulatis ; 

 labro clypeum late fortiter superanti ; antennis 9-articulatis ; 

 unguiculis bifidis. [Long. 3, lat. 1|- lines. 



The " trilobed outline " of the head is scarcely marked, owing 

 to the strong projection of the labrum and the almost obsolete 

 projection of the sides of the clypeus ; in the position most 

 favourable for showing a "trilobed outline" the appearance is 

 that of an almost continuous curve suddenly bulging out in the 

 middle — the portion thus bulging out being nearly as wide as 

 the lateral portions. The clypeus does not quite form an even 

 surface with the rest of the head, from which it is separated 

 by a feebly angulated suture ; its front is scarcely concave and 

 not distinctly margined. The prothorax is twice as wide as it 

 is long ; its base about half again as wide as its front, which 

 (viewed from above) is bisinuate, with feeble angles scarcely 

 produced ; it is widest a little in front of the base, its sides being 

 strongly arched, its basal angles scarcely defined from any point 

 of view ; its base very feebly convex all across. The elytra show 

 no stria tion beyond a feebly traceable sutural stria (probably 

 quite obsolete in some examples), their transverse wrinkling 

 quite obsolete, their puncturation very fine and close (a little 



