10 OLAVICOUNIA. [Silphidce. 



anterior coxse, which are conical and contiguous, and finely granulated 

 eyes which are sometimes wanting; the maxillae are Lilohed ; the antennae 

 are straight, inserted before the eyes, and thickened, or more often 

 furnished with a club ; the thorax is margined ; the prothorax has the 

 epimera and episterna not distinct ; the mesosternuni is short, and its 

 epimera reach the coxae ; the naetasternum is large ; the abdomen has, as 

 a rule, six free segments ; in SjjJuerites only it has five ; the legs arc 

 variable, sometiuies stout, sometimes slender ; as a rule the tibiae are dis- 

 tinctly spined externally ; the tarsi also vary as regards the number of 

 their joints. 



The family may be divided into the following tribes: there is, however, 

 a very great difference in the views of authors regarding the division : 

 Sphceri/es, for instance, is regarded by some as merely a genus of the 

 Silphina, by others as a tribe of the Silphidae, and by others as a separate 

 family Sphteritidae. 



I. Anterior coxal cavities closed behind. 



i. Posterior coxte laminate ; size very minute ; tarsi all 4-jointed 



in botli sexes Clambina. 



ii. Posterior coxa; simple ; tarsi variable, but never all 4-joiuted ia 

 both sexes. 



1. Upper surface, as a rule, glabrous or almost glabrous, shiniug ; 

 episterna of mesothorax small and linear, of metathorax 



hidden Anisotomina. 



2, Upper surface pubescent, dull; episterna of mesothorax rather 



large, subquadrate, of metathorax free Cholevina. 



II. Anterior coxal cavities open behind. 



i. Abdomen with five free ventral segments Sph.^.ritina. 



ii. Abdomen with six free ventral segments Silphina. 



CLAMBINA. 



This tribe has by many authors been placed in close proximity to the 

 Trichopterygida?, and it does in fact bear a close relationship to that 

 family, from the fact that the edge of the wings is fringed with long 

 hairs ; in other points, however, especially in the fact that in most 

 species the body is retractile and capable of being rolled up into a ball, 

 the tribe is closely related to Agathidium ; the head is large and 

 transverse, and the antennae 11 -jointed, 10-jointed, or 9-jointed, with 

 2-jointed club ; the anterior coxae are conical and contiguous with the 

 cavities closed behind, and the middle coxse in our two British genera 

 are slightly separated ; all the tarsi are 4-jointed ; the species are all very 

 minute, of convex and short oval form, and are found in decomposing 

 vegetable matter. 



There are two British genera which may be separated as follows : — 



I. Antenna) 10-joiuted, with club 2-]'ointed, inserted at a 



distance from eyes ; abdomen with six segments . . . Caltptojieexts, Redt. 



II, Antenna3 O-jointed, with club 2-jointed, inserted near 



eyes ; abdomen with five segments Clambus, Fiscli. 



