567 



A A. Prothoracic cavity not entirely glabrous ' : ' '*. ,' '•!; ;"/." 

 (usually densely clothed). 

 B. Lateral projections of prothorax not simple. 



c. Apical projection of prothorax bifid ... turrit us 

 cc. Apical projection simple. 



d. Black dispar 



dd. Reddish mullerianus 



BB. Lateral projections of prothorax simple. 

 C. Apical projection of prothorax simple. 



e. Elytra reddish semicalvus 



ee. Elytra black. 



/. Pronotum red and sparsely clothed ... monstrosus 

 ff. Pronotum black and densely clothed griseopilosus 

 CC. Apical projection of prothorax not 

 simple. 



D. Apical projection trifid (21) trifidus 



DD. Apical projection bifid. 



E. Elytra black nig.ripennis 



EE. Elytra reddish tectus 



Cavonus acutifrons, n. sp. 

 PI. xxxiv., fig. 29. 



<3 . Black and shining. Upper-surface glabrous ; under- 

 surface, legs, and upper part of pygidium with dense black 

 hair. 



Head transversely impressed and with numerous punc- 

 tures between eyes; clypeus large semicircular, margins rather 

 strongly elevated and undulating; mentum not very con- 

 spicuous. Antennae ten-, club three-jointed, seventh joint 

 very thin, rami of club about as long as head is wide. 

 Prothorax with a large and deep cavity bounded by a 

 conspicuous horn on each side and in front, the cavity with 

 transverse striae, elsewhere with punctures, becoming crowded 

 in front. Elytra scarcely wider than prothorax, slightly 

 longer than wide ; with rows of large punctures in well-defined 

 striae, the second and third rows on each elytron widely 

 separated from about the base to near the middle. Pygidium 

 with crowded punctures about base, smooth, and almost 

 impunctate elsewhere. Spurs of hind tibiae stout and 

 unequal. Length, 12 mm. 



Hab. — South Australia: Ooldea. Type (unique), I. 7820. 



The size of parvus, but excavation of prothorax larger 

 and with a tubercle on each side of it, clothing of under- 

 surface black, etc. ; armatus has prothorax somewhat similarly 

 armed, but the clothing of its under-surface is not black, and 

 the elytral punctures and striae are very different; sculp- 

 turatus (also from Ooldea) was described as being considerably 



(21) On a rare variety of trifidus the projection is bifid, but 

 the species is otherwise abundantly distinct from tectus and 

 nigripennis . 



