.TlIK CAUETON HEKTLKS. 



289 



tate. Elytra broadly oval, continuing the curve of the thorax; surface 

 irregularly punctate, sometimes with larger punctures forming sinuous rows 

 near the sides and suture. Hind femora of male with a broad, acute tooth 

 at apex. Length 1.6-2 mm. 



Starke County; rare. June 17. Larger and darker than egena, 

 with the legs less thickened and the tarsi more slender. 

 562 (1792). CYRTUSA EGENA Lee., Proc. Phil. Acad. Nat. Sci.. 185:'., l's4. 



Oval or subglobose, very convex. Pale brownish-yellow, shining. Thorax 

 more than twice as wide as long, narrowed in front; surface sparsely and 

 very finely punctate. Elytra each with eight somewhat irregular rows of 

 very fine punctures; intervals flat, smooth, or rarely with a few fine punc- 

 tures. Tarsi very short and much compressed. Length 1-1.5 mm. (Fig. 

 143, e.) 



Marshall, Monroe and Perry counties ; scarce. May 1 6-June 10. 



Isoplastus fossor Horn, hemispherical or broadly oval, very con- 

 vex, reddish-yellow in line, length 1.5-2 mm., was described from 

 Detroit, Michigan, and the District of Columbia. 



XIII. AGATHIDIUM Illig. 1798. (Gr., "good -f little one.") 



Very small black or piceous shining beetles having the labrum 

 short, rounded in front; antenna? with joints 4-8 small, gradually 

 broader, 9-11 forming an 

 oblong rather loose club. 

 They occur beneath bark f 

 or in fungi and are more 

 or less contractile, some of 

 them having the power to 

 roll themselves into a very 



Convex rounded maSS, With Fig. 144. a, Agathidium oniscoides; b, upper, same, contracted; 



n [lower, ^4. politum (male) contracted; c, Aglyptus lavis; a, antenna 



the legs bent under and] ; f same. 



completely hidden. Three species have been taken in Indiana, while 



another probably occurs. 



KEY TO INDIANA SPECIES OF AGATHIDIUM. 



"IT^Mesosternuui continuous on the same plane with the metasternum, mod- 

 erately separating the middle coxae and subcarinate in front ; elytra 

 polished, without punctures; third joint of antennae longer than sec- 

 ond. 



&. Larger species ; sutural striae very fine. 563. ONISCOIDES. 



l>l>. Smaller species; sutural striae distinctly impressed. 



r>r> 4. EXIGUUM. 



(ia. Mesosternum vertical between the coxae, which it narrowly separates, 

 not carinate in front; hind angles of thorax broadly rounded; body 

 very convex and contractile. 



