78 TERTIARY COLEOPTERA OF NORTH AMERICA. 



The species agrees best perhaps with G. nigritus Miill., but is not very 

 close to any, differing- in the granulated structure of the body and the 

 absence of any posterior collar-like constriction of the thorax. 



Length of fragment, 5.1 mm.; of thorax, 1 mm.; of elytra, 1.75 mm.; 

 breadth of thorax, 1.1 mm.; of elytra, 1.85 mm. 



Florissant, Colorado; one specimen. No. 2186. 



Geodromicus stiricidii. 

 Geodromieus stiricidii Scudd. , Contr. Canad. Palseont., II, 43, pi. 2, fig. 1 (1892). 

 Clay beds of Scarboro, Ontario. 



ARPEDIUM Erichson. 



A widespread genus, with a very limited number of species, of which 

 nearly half a dozen occur in North America. The only fossil known is 

 one from the Canadian Pleistocene, here recorded. 



Arpedium stillicidii. 

 Arpedium stillicidii Scudd., Contr. Canad. Palseont., II, 42-43, pi. 2, fig. 2 (1892). 

 Clay beds of Scarboro, Ontario. 



TRIGA Fauvel. 



A North American monotypic genus, which is represented in the earlier 

 Tertiaries by a species from Colorado. 



Triga cceni sp. nov. 



Pi. IX, fig. 5. 



Head orbicular, with barely prominent eyes, about half as broad again 

 as the brief constricted neck, smooth, with distant, exceedingly brief hairs 

 set in minute punctures. Antennae with only the three or foiu- basal joints 

 preserved, and these imperfectly, but they indicate nothing at variance with 

 those of T. picipennis LeC, unless they are stouter. Thorax slightly wider 

 than the head, transversely suborbicular, slightly broader than long, trun- 

 cate at apex, but well rounded at base and regularly convex on sides, with 

 a faint median stria, the disk very sparsely and feebly punctate, the puncta 

 giving rise to moderate hairs. Elytra a little wider, but scarcely longer 



