Choleva.'] CLAvicOKNiA. 59 



fact that the antenna; are in almost all cases distirictly thickened towards 

 apex ; the genus Cafopomorphus, of which there is no I>ritish repre- 

 sentative, forms a connecting link between this and the preceding 

 sub-genus ; the species belonging to this last-named genus are dis- 

 tinguished by the very long last joint of the antennre and by their being 

 always found in ants'-nests. The name Ptomopliagus has been by many 

 authors applied to C. sericeus and C. varicornis, while the name Catops 

 has been retained for the species belonging to the present sub-genus ; 

 as, however, the type species of Catops described by Paykull appears to 

 have been C sericeus, it appears more correct to confine the name of 

 Catop)S to the species with truncate elytra. 



The species belonging to the sub-genus Ptomapliagus are, in many 

 cases, extremely hard to determine with certainty ; this is more espe- 

 cially the case with C. trlstis and its allies, which appear as a rule to be 

 mixed in collections ; the differences in one or two cases are so slight, 

 that it is doubtful whether all the species can really be considered as 

 distinct ; in fact Murray regards G. longula, C grandicollis, and O. 

 rotund kollis ( = Kirhi/i), and the two continental species G. abdominalis 

 and G. montivaga as all varieties of G. tristis. 



I. Thorax more or less distinctly narrowed before base. 

 i. Pubescence greyish or yellowisli ; antenna9 rather 

 long, slender, or more or less distinctly thickened 

 towards apex. 

 1. 'J'horax with sides rounded completely to base, 

 not sinuate before posterior angles. 



A. Antenna; long and slender, only slightly 

 thickened towards apex, with sixth joint al- 

 ways longer than broad in male, sometimes 

 as long as broad in female ; size larger (4- 

 5 mm). 



a. Colour fuscous-brown ; posterior angles of 



thorax scarcely projecting C. FUSCA, Panz. 



b. Colour black ; posterior angles of thorax 



distinctly projecting C. NIGBICANS, Sjpence. 



B. Antenna; moderate, distinctly, but not strongly 

 thickened, with sixth joint about as long as 



broad in male, sometimes transverse in female. 



a. Antennse with joints 6-8 of nearly equal 



length, feebly transyerse C. LONGULA, Kell. 



b. Antenna; with eighth joint half as long as 



sixth, strongly transverse, 

 a*. Last joint of autennje as broad as penul- 

 timate ; thorax not quite as broad as 

 elytra. 



af. Elytra shorter ; antennse ferruginous 



with darker club C. COEACINA, Kell. 



bf Elytra longer ; antenna; dark with first 



two and last joints reddish yellow . . C. mokio, F, 

 b*. Last joint of antenna; narrower than 



penultimate ; thorax ample, fully as broad 



as elytra C. GRANDICOLLIS, Er. 



