520 REVISION OF THE AUSTRALIAN SPECIES OF BOLBOCERAS, 



at all concave. The unique type has unfortunately lost its tibiae, 

 but it is very unlikely that they were materially different from 

 those of B. mandibulare, Blackb. The frontal margins are (in 

 front of the frontal wings) as short as in B. nitidiceps, Blackb. 

 N. Queensland (sent by the late Mr, Cowley). 



B. ROTUNDATUM, Hope. 



I have, in my collection, specimens from the Port Essington 

 region which I have no doubt are this species. Their front tibiae 

 have the 6th (uppermost) external tooth either wanting or very 

 nearly so. The 14th and 15th elytral striae are confluent in 

 their front portion, the eyes not visibly faceted. The pronotum 

 is longitudinally impressed along the middle, but otherwise 

 devoid of inequalities (except the sublateral foveae). The front 

 part of the frontal margins is as in nitens, Blackb., and niti- 

 diceps, Blackb. The hind femora are strongly but not closely 

 punctulate. The difference between the sexes is slight, and of 

 the same kind as in B. mandibulare, Blackb. 



B. RUBESCENS, Hope. 



I have a single specimen from the Port Essington region 

 which I conjecture to be this species. If I am right in my 

 identification it is, I think, distinct from B. rotundaium, Hope, 

 though (as Westwood says) extremely close to it. Besides the 

 slight differences noted by Westwood (which, if they w^ere all, I 

 should not consider specific), its eyes are visibly faceted, its 

 clypeal elevation is scarcely tuberculate in the middle, and the 

 carinse connecting the quasi-tubercle with the extremities of the 

 frontal margins are evidently less oblique, so that they scarcely 

 form an angle at their point of contact with each other. 



B. IMPRESSICOLLE, Sp.nOV. 



Mas C?). Breve; subrotundatum ; nitidum ; supra glabrum ; 

 subtus hirsutum; rufobrunneum; mandibulo sinistro (superne 

 viso) extus vix sinuato; capite fere ut B. mandibularis, Blackb., 

 maris, sed fronte pernitida sparsim punctulata, eminentia frontali 



