614 



FAMILY XXV. HISTERIDiE. 



III. Tribalus Erichs. 1834. (Gr., "worthless.") 



This genus contains two small, dull blackish, ovate species, hav- 

 ing the antennas inserted under the margin of the front, their 

 cavities at the front angles of thorax open both in front and on 

 sides. One of the two occurs in Indiana. 



1172 (3531). Tribalus americanfs Lee, Bost. Journ. Nat. Hist., V, 1845, 



64, pi. IV, fig. 7. 



Broadly oval, convex. Black or piceous, feebly shining, densely punc- 

 tured. Thorax without stria?. Elytra with four ill-defined dorsal stria?, 

 the first and second apical, third and fourth basal. Pygidium and propy- 

 gidiuni finely and densely punctured, the former vertical. Length 2.3- 

 2.8 mm. 



Southern half of State ; scarce. April 24— June 16. Occurs be- 

 neath bark of hickory, black gum and elm. 



IV. Epierus Erichs. 1834. (Gr., "pleasing.") 



Small, oblong-oval forms, easily distinguished from Tribalus by 

 the distinct elytral striae. As there, the antennal cavity is partly 

 concealed by the pectoral plate and is open in front and on the 

 side. Our two species have all the dorsal striae entire. 



1173 (3533). Epierus regularis Beauv., Ins.. 1805, 180. 



Oblong-oval, convex. Black, shining; legs piceous. Thorax rather 

 sparsely punctate with larger and smaller punctures intermingled. Elytra 

 each with six entire punctured dorsal striae; intervals sparsely and minutely 

 punctulate; subhumeral entire; epipleural fold coarsely punctured and with 

 two deep, distinct stria?. Length 2.5-3 mm. 



Throughout the State ; frequent. April 9-September 10. Oc- 

 curs usually in fungi. 



*1174 (3535). Epieres pelicarius Erichs., Jahrb., 1834, 162. 



Oval, moderately convex. Dark reddish-brown or piceous, shining. 

 Thorax finely and sparsely punctured. Elytra with six entire dorsal stria?; 

 subhumeral entire. Epipleura with one fine stria. Length 1.5-2 mm. 



Southern half of State, common ; less so in the northern coun- 

 ties. February 23-October 4. Gregarious in winter beneath bark 

 and logs in low. moist ground. Easily distinguished from regu- 

 laris by the smaller size, lighter color and one stria of epipleura. 



V. Het^rius Erichs. 1834. (Gr., "friendship.") 



Readily known by the peculiar lobe on each side of thorax. 

 Pour species are listed from the United States, one of which occurs 

 in Indiana. 



