162 



BRITISH BEETLES. 



ties into which these coxae fit is different from that of 

 all the other Heteromera, as they are not open on any 

 side. 



The TETRATOMTD^E, also, are very unlike their neigh- 

 bours, having the facies of certain species of Cis, and 

 of some of the Dermestidae. Their antennae are termi- 

 nated by a distinct club of four joints; their head is 

 much bent down, being scarcely visible from above; 

 their anterior coxae are cylindrical, transverse, separated 

 by a projection of the prosternum, and with their coty- 

 loid cavities widely open behind. 



All the species are small, rather cylindrical, and 

 strongly punctured, and are found in partly decayed 

 wood. One (Tetratoma Desmarestii, occurring at Coombe 

 Wood, and elsewhere) is blackish-green; another (T.fun- 

 gorum) is blue-black, with a red thorax; and the 

 remaining one (T. ancora, recently taken in some num- 

 bers in old stumps near Highgate) is testaceous, spotted 

 and banded with brownish-black. All of them must be 

 considered rare. T. fungorum superficially resembles 

 certain species of Triplax in the Pseudotrimera, but 

 the latter genus can be easily known by the three- 

 jointed club to its antennae, and the lesser number of 

 joints to its tarsi. 



The position of this family is anything but firmly 

 established, and it appears to have been placed in its 

 present place chiefly faute de mieux. 



The MELANDRYAD^E have the labial palpi very short, 

 and the maxillary palpi much developed, often with the 

 joints indented, and with the apical joint very large. 

 The cotyloid cavities for their anterior coxae are open 

 behind ; the claws of their tarsi are simple ; and the 

 upper part of the prothorax is not continued until it is 



