LAND SCAVENGER-BEETLES. 55 



Indeed, in some of the families which are usually classed with the pen- 

 tamerous clavicorns, both of the leading characters, the clubbed antennte 

 and the five-jointed tarsi, either partially or wholly fail. Some of these 

 insects also depart widely in their habits from the scavengers proper, 

 and might therefore very properly be separated as a tribe by themselves 

 were it not for the absence of any very strongly marked community of 

 characters. In order to guard against mistake we have thought it best 

 to tlirow these exceptional families together, as a sub-tribe, under the 

 title of sub-clavicornes. 



The tribe of land-scavengers may therefore be divided into two sub- 

 tribes differing very considerably from each other, both in structure and 

 habits, and which may be distinguished as follows: 



1st Sub-tribe. — Glavicornes, proper. Body more or less oval ; antennsB 

 clavate or cax)itate ; usually three, sometimes more than three joints in 

 the club ; usually five joints in all the tarsi, or, at least, in the anterior 

 ones 5 subsist mostly upon animal or vegetable substances, in a state of 

 decay. This division includes the families Silphid£e, Scaphidiidaj, His- 

 teridiTi, ISTitidulidte, Dermestidse, Mycetophagidte, Cryptophagida?, 

 Byrrhidic, Anisotomidai, Phalacridiie, Trichopterigidse and Scydmenidre. 



lid Sub-tribe. — Suh-clavlcornes. Body more or less elongated ; anten- 

 nne almost filiform, or granose, or moderately and loosely clavate, some- 

 times with less than three joints in the club ; tarsi, in many, less than 

 five-jointed. Found mostly under the bark of dead trees. They never 

 feed upon dead animal matter, but recent observations show that many 

 of them are carnivorous or vermivorous, at least in their larva state, 

 preying upon the soft larv« of the wood and bark-eating insects. 

 Composed of the families Trogositidifi, Cucujidae, Colydiid;e and Lath- 

 ridiidse. 



FAMILIES OF LAND-SCAVEKGERS 

 Sub-tribe 1st. Clavicornes. 



A. Body oval or elliptical 5 antennae clavate or capitate. Anterior 

 tarsi almost always five-jointed. 

 B. Large insects, the smaller not much less than half an inch in 

 length (except Catops.) Hind trochanters prominent. 



Thorax with a thin margin Silphid^. 



B B. Small insects less than half an inch, mostly less than quarter 

 of an inch in length. 

 0. Wing-cases shorter than the abdomen. 

 D. Abdomen thick, conical and pointed, first segment very 



loug - SCAPHIDILD^. 



D D. Abdomen rounded behind. 



