THI VARIEGATEE MUU-LOVIN(, BEETLES. 663 



presence or absence of the post-nusocoxaJ line. This is an elevated 

 line on the metasternum which "begins at the middle of the hind 

 border of the middle coxa? and extends obliqnelj^ backward, joining 

 the suture between the metasternum and its episternum. " The 

 first ventral segment bears a stridulating organ in the shape of an 

 elevated curved ridge ^^■hich is finely striate transversely, and when 

 rubbed by the hind legs, produces a quite distinct sound. Of the 

 11 species recognized by Horn, seven have been taken in Indiana, 

 while another may occur. 



KEY TO INDIANA SPECIES OF HETEROCERl'S. 



i(. Thorax with a pale median stripe; stridulatiug rid^'t of tirst ventral 

 segment complete, forming nearly a semicircle ; an elevated obliirue 

 line on the epipleura near the base. (Fig. 256, c. ) 



1302. AUROMICA.NS. 



ua. Thorax without a pale median stripe; stridulating ridge of first ven- 

 tral iiH-(jmplete, extending from the front angle in a curved line to 

 hind border ; epipleura without an oblique elevated line near the 

 base. 

 h. Jletasternuin without a post-mesocoxal line; elytra never with a spot 

 at base near suture, 

 c. Labruin of male narrowed at tip and prolonged forward in a 

 process; size larger, 6 mm.; elytra obsoletely substriate. 



1303. VENTHAUS. 



re. Ivabrum of male not prolonged forward in a process; size smaller, 

 not over 4.5 mm. ; elytra usually distinctly substriate. 



1304. rNiiATi's. 

 hb. Mctasteriium with a post-niesdcoxal line. 



(1. Elytra usuiilly brownish or piceous, always with more or less dis- 

 tinct dull yellow spots or mnrkiugs ; mandibles of male without 

 basal lobe extending over the labrum. 

 e. Elytra without a jjale spot at base near suture. 



/. Elytra usually substriate. the pale markings much broken ; 

 legs more or less piceous ; larger, 3.-5-4 mm. 



I.jO.j. bbu.\xeus. 

 /f. Elytra not substriate, the markings well defined and broad ; 

 legs wholly pale; length not over 3 mm. schwakzi. 



cc. Elytra with a pale spot at base near suture. 



g. General color of upper surface brownish or jiale ; thorax mere- 

 ly slightly darker at middle; mandibles of male with an 

 angulate basal lobe on outer side. 1300. coliakis. 



gg. General color piceous ; thorax iiiceons, often sharply bordered 

 with pale; mandibles of male not prominent at base, 



1307. TEISTIS. 



d(l. Elytra pale without yellow marks, often with a broad fuscous 

 sutural s|iace; mandibles of male with a basal loI)e extending 

 over the base of labrum. 130S. PtisitLUS. 



