flL!4 VAMILY L. — SCARAB.KIDiE. 



IX. AiVENius Harold. 1867. (Gr., "without a fetter.") 



Small, slender, blackish insects resembling Aphodius, but usu- 

 ally smaller -and more elongate. The head is convex, not tubercu- 

 late; eyes usually concealed; hind tibia' simple, straight, the outer 

 apical angle more prolonged than in Aphodivs and often ending in 

 a spine. The stvia3 of elytra often appcnr more coarsely punctured 

 than they really are, due to the sides of the intervals being crenate, 

 this crenation being entirely independent of the punctures of the 

 strife, which are fine and distant. The "accessory spihule" of the 

 hind tibiffi mentioned in the key below is a prolongation of the 

 apical margin on the under side near the spurs. Seven species have 

 been taken in Indiana, ivhile two others perhaps occur. 



KEY TO INDIANA SPECIES OF AT^NIUS. 



a. Clypeus feebly emarginate at middle, broadly rounded on each side, 

 never dentate nor subangulate. 

 6. Opaque species ; thorax without basal marginal line ; head densely 

 and finely punctured, not wrinkled; hind tibife without accessory 

 spinule. 



c. Elytral intervals flat. 1743. imbeicatus. 

 CO. Elytral intervals alternately more elevated. 1744. alternatus. 



hi. Shining species ; thorax with basal marginal line. 



d. Hind tibioe without accessory spinule. 



e. Elytra oblong-oval, base slightly emarginate; form rather ro- 

 bust ; thorax unequally and irregularly punctured. ovatuujs. 

 (■<:. Elytra elongate, parallel, base truncate; form slender, elongate; 

 thorax evenly and densely punctured. 1745. gracilis. 



dd. Hind tibiae with accessory spinule. 



/. Clypeus finely punctured without traces of wrinkles; occiput 

 with coarse punctures. steigatus. 



//. Clypeus more or less wrinkled and coarsely punctured; thorax 

 with coarse and fine punctures intermingled. 1746. cognatus. 

 au. (Jlypeus subangulate, or sometimes denticulate each side of the median 

 emargination. 

 g. Thorax nearly smooth in front, coarsely and rather sparsely punc- 

 tured behind the middle, more densely at sides ; intervals of elytra 

 convex ; marginal line of hind femur deep and entire. 



1747. lecontei. 



fifl. Thorax nearly evenly punctured from base to apex ; marginal line of 



hind femur very short or absent. 



h. Piceous species ; first .inint of hind tarsus as long as the long spur ; 



thorax densely punctured. 174S. abditus. 



hh. Reddish-brown; first joint of hind tarsus shorter than the long 



spur; thorax regularly not densely punctured, the punctures a 



little finer in front. JY49_ inops 



