MYCETOPHAGIDAE. 139 



Head sliort ; frontal suture distinct in the first tribe, 

 wanting in the third; labrum short, covering the mandi- 

 bles, which are short, acute, and not prominent. 



Prothorax with the side pieces not separate, as wide as 

 the elytra at the base ; anterior coxal cavities open behind 

 in the first tribe, closed in the tliird. 



Mesosternum narrowly separating the middle coxas. 



Metasternum moderate, side pieces narrow. 



Elytra usually covering the abdomen, and rounded at tip. 



Abdomen with five free and equal ventral segments. 



CoxiB, anterior oval, rounded, somewhat prominent; mid- 

 dle rounded; posterior transverse, not contiguous. 



Legs slender; tibias nearly linear, with small terminal 

 spurs; tarsi filiform, 4-jointed in the first and second tribes; 

 lobed beneath, and 5-jointed, with the fourth joint small, in 

 the third tribe; ungues simple. 



The insects of this family live on fungi and under bark. They 

 are oval, rarely elongate, slightly convex, densely punctured, and 

 hairy. Many have the elytra handsomely variegated with spots. 



Tarsi filiform, 4-joivited. 



Front tarsi % 3-joiiited. Mycetopiiagini. 



Tarsi similar in the sexes. Mykmeciiixeni. 



Tarsi lobed beneath, 5-jointed. Dipuyllini. 



Tribe I.— MYCETOPHAGIIVI. 



The species of this tribe are finely punctured insects, clothed 

 with prostrate hair. The anterior coxal cavities are open ; the 

 tarsi are 4-jointed and filiform, the anterior pair in the male 

 having but three joints. The frontal suture is always distinct, 

 and usually deep. 



Our genera are : — 



Eyes transverse ; 



AntennjB gradually enlarged externally. Mycetophagus. 



Antennse with joints 9—11 suddenly larger. Triphyllus. 

 Eyes rounded ; antennae with joints 9-11 suddenly larger ; 



Clypeal suture not deeply impressed. Litargus. 



Clypeal suture deep. Typhaea. 



Eyes rounded ; antennae with joints Id-] 1 suddenly larg<'r. Berginus. 



Mycetophagus and Ijitargus are generally diffused ; Ti/phifo, 

 fumata has been imported by commerce, and is found in houses. 

 One species of Triphyllus is found on each side of the continent. 

 Berginus occurs in Pennsylvania. 



