ST APHYLINIDAE. 1 1 



Lathrium Lee. is uot sufficiently distinct from Olophrum, and 

 the species L. convexicolle from Lake Superior greatly resembles 

 0. conuexum Miiklin from Russian America. 



Tribe VIII.— PROTEOIAI. 



This tribe contains a very small number of species, approaching 

 closely to the preceding tribe, but differing by the prosternum 

 being corneous behind the coxae, a^d by the head having no ocel- 

 lus in our genera, and but one in certain foreign genera. The 

 antennas are inserted under the sides of the front; the anterior 

 coxa? are transverse, subcorneal, and somewhat prominent; the 

 hind coxae are transverse ; the hind trochanters are at the inner 

 margin of the thighs ; the tarsi are 5-jointed. The species live 

 in fungi and under bark. 



Our two genera without frontal ocellus are distinguished by 

 the form of the antennae. 



Antennas with the joints 9 — 11 larger. Pkoteinps. 



Antennas with the eleventh joint only larger. Megarthrus. 



The latter genus is further remarkable for having the sides of 

 the thorax frequently with an angle behind the middle ; the thorax 

 is also always channelled. 



Tribe IX.— PHX4EOCHARINI. 



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

 slender, depressed form, and is represented in our fauna only by 

 the genus Olisthaerus, found in the northern regions, from Canada 

 to Russian America, under bark. 



The prothoracic spiracles are covered ; the thorax behind the 

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

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

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



The antennae are 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 Omalini by the 

 absence of ocelli, and from Tachyporini only by the prothoracic 

 spiracles being covered. 



In Olisthaerus the anterior tarsi are not dilated, and the maxil- 

 lary palpi are filiform. 



