510 Transactions South African Philosophical Society, [vol. xii. 



F-*. Apical part of posterior tarsi ciliate and with- 

 out an apical spine. 



Mentum elongato-ovate with the ligular part 

 dilated ; maxillae four- or five-dentate, in the 

 latter case the basal tooth is bifid Pentodontoschema . 



Mentum lanceolate at tip, maxillae six-dentate Hijboschema. 



Mentum elongate, acuminate at tip ; maxillse 



small, not dentate Orsiloclms. 



F^. Apical part of posterior tibiae neither ciliate 

 nor spinose. 



Frontal carina raised in a vertical wall in 

 both sexes ; posterior tibiae very broadly 

 dilated Tcmnorliynclius. 



Frontal carina normal ; clypeus acuminate . . Callistenionus. 



T)\ Maxillae rounded, very convex ; apical part of 



anterior tibiae ciliate. 



F=. Clypeus very narrow, lanceolate ; club of 

 antennae uniform, moderately long ; mentum 

 very sharply acuminate at tip Pijchnosclienia. 



F^ Apical part of anterior tibiae slightly ciliate 

 and triangular. 



Clypeus not very narrow ; club of antennae 

 very long, laminiform ; mentum convex at 

 base, deeply excavate at tip and emarginate 

 there Hoiucconiorplius. 



B'. Intermediate and posterior tibiae digitate at apex, 



b~. Claw of anterior tibiae thickened in the 

 male. 



Mentum elongato-ovate, and with the ligular 

 part strongly constricted laterally and ex- 

 panding triangularly at tip ; maxillae five- 

 dentate .. .. : .r Cyplionistes. 



fe^ Inner claw of anterior tarsi of male not 

 thickened. 



Mentum small, oblong at tip ; maxillae con- 

 cave, transverse, not dentate Oryctes. 



Mentum elongato-ovate with the apical part 

 emarginate ; maxillae strongly arcuate at tip 

 and briefly bifid at apex and at base . . . . Arclion. 



W Labial palpi inserted in the inner part of the mentum. 

 B=. Intermediate and posterior tibiae non-digitate at 

 apex. 



