98 COLEOPTERA OF NORTH AMERICA. 



is corneous in some, membranous in others ; the anterior coxte 

 are large, conical, and prominent; the posterior coxae also conical 

 and prominent ; the antennjB are inserted under the sides of the 

 front ; the mandibles are long and slender ; the palpi with the 

 last joint usually minute. The abdomen is margined in all of our 

 genera, except Stictocranius and Palaminus. The hind trochan- 

 ters project inwards but slightly. The head is always narrowed 

 suddenly behind, forming a distinct neck. 

 Three groups seem to be indicated : — 



Tarsi 4-joiiite(i. Eu^stheti. 

 Tarsi .5-jointed. 



Palpi with the last joint very small, subulate. PvEDERi. 



Palpi with the last joint equal to the preceding. Pinophili. 



Group I. — Euaestheti. 



The eyes are moderate in size, and but slightly prominent; 

 the antennceare inserted before the eyes, at the base of the labrum, 

 which is denticulate anteriorly. The tarsi are 4-jointed. 



Body smooth. 2. 



Body punctured. Euassthetus. 



2. Abdomen margined. Edaphus. 



Abdomen not margined. Stictocranius. 



The species, thus far, are found only iti the Atlantic district. 

 Edaphus possesses but one species, E. nitidux, from Louisiana ; 

 it is remarkable for simulating in appearance a Pselaphide of the 

 tribe Euplectini. The head is marked with two deep fovese, and 

 at the base of the thorax are three others. The upper surface is 

 smooth, and the elytra are slightly pubesc(!nt; the color is uni- 

 form, yellowish-red. Stictocranius occurs in ants' nests at Wash- 

 ington, D. C. Eua?sthetus lives on flowers. 



Group II. — Peederi. 



The genera of this group are numerous, and are found under 

 bark, under stones, and near water. The form of the palpi readily 

 distinguishes them from the second group. 



A. Hind tarsi with the fourth joint not lobed (prosternum behind the 

 coxae membranous) ; 



Antennae geniculate. Cryptobium. 



Antennae straight ; 2, 



