54 STUDIES IN AUSTRALIAN ENTOMOLOGY. 



indistinct on declivous part of sides ; obsolete towards apex ; no 

 scutellar striole ; lateral border broad, reflexed^ widened and 

 flattened on each side near the peduncle ; about six widely placed 

 setigerous punctures along each margin. Prosternum with an 

 entire border along anterior margin. Ventral segments strongly 

 divided, last segment with a single puncture on each side of anus. 

 Anterior tarsi broad, three basal joints obliquely produced on 

 external side and clothed below with spongiose tissue. 



Length 12, breadth 4-^ mm. 



Hnh. — New South Wales; Mount Kosciusko (Helms), Burra- 

 wang (Sloane). 



The three remaining genera form a natural group characterised 

 by having the mandibles without a setigerous puncture in the 

 scrobe, and the prosternum not bordered along its anterior margin. 



The following is a brief summary of the features that may be 

 used to separate them from one another : — 



Form short ; prothorax subquadrate, hardly at all narrowed 

 behind. Head without a transverse impression behind eyes. 

 Antennae moniliform, short, thick Percolestus. 



Head with a transverse impression behind eyes, and deep 

 frontal grooves. Antennae moniliform Lychrius. 



Form elongate ; prothorax subcordate, greatly narrowed behind. 

 Head without transverse impression behind eyes or deep frontal 

 grooves. Antennae subfiliform, not thick Percosoma. 



Percolestus, n.g. 



Head moderate, lightly impressed on each side behind the 

 eyes ; eyes spherical, prominent ; temporal ridge obsolete ; one 

 supra-orbital puncture on each side. 



Mandibles short, broad, arcuate, obtusely hooked at apex ; 

 inner edge not dentate ; scrobe without setigerous puncture. 



Alaxillce short, not projecting beyond labrum, hooked at apex. 



Labrum short, sexsetose, truncate, anterior angles rounded. 



