STAPHYLINIDAE. 101 



Maxillary palpi filiform. Bolitobiiis. 



Maxillary palpi with the last joint conical, acute Bryoporus. 



Maxillary paljji subacute. Mycetoporus. 



In Bolitobius the liead is often elongate, tlie tibite fimbriate 

 at tip with unequal spinules, Bryoporus has the spiniiles short 

 and equal, while in Mycetoporus the species vary between the 

 two forms. These genera are represented on both sides of the 

 continent. 



Group V. — Habroceri. 



This group contains in our fauna but one genus, easily known 

 in the tribe by its capillary autennce, and the form of the posterior 



COXffi. 



Habrocerus occurs in the Atlantic region, and contains two 

 species. 



Tribe VI.— PHLtEOCHARIlVI. 



This tribe consists also of a very small number of species, of 

 slender, depressed form. 



The prothoracic spiracles are covered ; the thorax behind the 

 anterior coxte is membranous ; the latter are conical and promi- 

 nent, and the hind coxaj are transverse; the hind trochanters are 

 on the internal margin of the thighs; the tarsi are 5-jointed. 



The antennae arc inserted under the sides of the front, straight, 

 11-jointed, scarcely thickened externally. The second ventral 

 segment is longitudinally elevated at the middle. 



It will thus be seen that this tribe differs from Homalini by the 

 absence of ocelli, and from Tachyporini only by the prothoracic 

 spiracles Ijeing covered. 



Prothorax not costate ; max. palpi filiform : mandibles simple. Olistheerus. 

 Prothorax costate ; max. palpi subulate ; mandibles toothed. Pseudopsis. 



Of Olisthaerus there are but two species found in northern 

 Europe and Canada. Pseudopsis is represented by one species, 

 abundant in Canada, very rare in Europe, and by another species 

 in Arizona. 



Tribe VII.— OXYTELIIVI. 



The prothoracic stigmata are covered by the inflexcd portion 

 of the pronotum; the anterior coxfe are large, conical and promi- 

 nent; the second ventral segment is w^ithout any ridges. The 



