128 MANDIBULATA. — COLEOPTERA. 



This subsection includes the two following indigenous families, 

 which may be readily known by the subjoined concise definitions: 



( haud fractEe : mandibulce non exsertas : .22. Byrrhid^e. 



• Antenna^ 



(.fractse: mandibulce exsertae: . . . 23. HisteriDjE. 



Family XXII.— BYRRHID^, Leach. 



Palpi subclavate or filiform, equal : maxilla? bifid : mandibles not exserted : an- 

 tenna? thickened towards their extremities, the articulations of not very dis- 

 similar length, the club composed of from three to five joints : head small, 

 very convex, deeply inserted into the anterior margin of the thorax ; the latter 

 very short, much narrowed anteriorly, with the lateral margins considerably 

 deflexed : sternum anteriorly produced : body ovoid, very convex, more or 

 less pubescent : elytra entirely covering the abdomen : legs contractile ; tibia? 

 more or less compressed, with an external groove to receive the tarsi, which 

 are distinctly pentamerous. 



The Byrrhidse are so intimately allied to the Dermestidse, that 

 Latreille includes Megatoma and its allies in the former family in 

 his Genera, and in the latter in the Regne Animal : and there is very 

 great similarity between the larvae of the genus last mentioned 

 and those of the genus Anthrenus : — in the perfect state, some of 

 these insects are found in sandy or gravelly situations, in fields, 

 roads, &c. : others occur in flowers, beneath the bark of trees, or 

 by the coast, in chalk-pits, &c. : the larvae of the Anthreni are 

 destructive to animal substances, but those of the typical genus 

 Byrrhus are unknown. 



The following is a tabular view of the indigenous genera, which 

 may be distinguished by the subjoined, chiefly external, characters: 



ftrilobus. Corpus 



,3 f3-articulato. I 



Thorax< 



"squamosum: 174. Anthrenus. 



dense pilosum: 176. Trinodes. 

 subpubescens : 175. Aspidiphorus. 



P os ice (punctata: 178. Nosodendron. 



(^rotundatus. Elytra < 



(striata: 177- Syncalypta. 



Struncato: . 179- Byrrhus. 



acuto: . 180. Simplocaria. 



Genus CLXXIV. — Anthrenus, Geoffrey. 



Antenna; very short, concealed during repose in a groove beneath the sides of the 

 thorax, terminated by a solid triarticulate club, the last joint of which is larger 



