THK WATER S(\\VRXr.ER BEETLES. 2()7 



a. Elytra iiiooous, with -a comrann indefinite pale space rlividod 

 by the siitnro. Imt n 't reaehins apex; sides of tlr^rax aivl 

 humeral unibone i)ale. iNinsTiNCTUs. 



Iili. F(irni short, very convex; liead vertical; lu'ictuatinn of elytral 

 intervals more indistinct tlian that of thorax. 

 j. Surface opaque, more or less alutaceous; elytra with distinct 

 strife; apex with a distinct pale spot. 

 /.•. Entire surface alutaceous; elytral strl.-p fine, but reaching 

 apex. 524. lugibris. 



A/.-. Elytra alone alutaceous. their striio very fine and not 

 reaching the apex. 525. tristis. 



jj. Surface shining; elytral striae replaced by rows of fine punc- 

 tures; apex with an indistinct rufous space extending 

 slightly along the suture. 526. navicularis. 



gg. Interval between the seventh and eighth strue narrow and with 

 but one row of punctures. 

 /. Elytra with an Indefun'te jiale space at apex; color plceous or 

 brownish. 527. analis. 



//. Elytra with pale space at apex shar])ly limited by a curved 

 line, not extending along the side margin ; color black, shin- 

 ing. 528. OCELI.ATUS. 



51S (1664). Cercyon pubescens Lee, Proc. Phil. Acad. Nat. Sci., VIT. 1855, 

 374. 

 Oval, moderately convex, somewhat attenuate l)ehind the middle. Dull 

 reddish-brown, sparsely pubescent; head piceous. Thorax twice as wide 

 as long, narrowed in front, sides cun'ed from base to apex; surface sliglitly 

 rugose, without punctures. Elytra with nine rather deeply impressed punc- 

 tured strite; intervals flat on basal half, convex and alteruiitely more ele- 

 vated at apex, very finely and sparsely punctate. Mesnsternal elevation 

 elongate-oval, acute in front, truncate behind. Length 1.5 mm. 



Lawrence County; frequent at carrion bait and on fungi. June 

 10-July 29. Probably throughout the State but overlooked on ac- 

 count of small size. Said to be often abundant in dried horse dung. 



519 (1666). Cercyon h.emokrhoidalis Fab., Syst. Eut.. 1798, 67; 



nigricolle Say, Ed. Lee, II, 294. 

 Oval, moderately convex. Elytra piceous or brownish, their tips slight- 

 ly paler than disk. Thorax closely punctate. Elytra 10-striate, the stria* 

 distinct at apex, rather closely punctate; intervals flat, densely and rather 

 coarsely punctulafe. Length 2.5-3 mm. 



Marion, Putnam and Posey counties; frequent. April 6-Octo- 

 ber 17. This is the species listed as favipes Fab. and nigricolle 

 Say. 



520 (1672). Cercyon mklanocephalus Linn., Faun. Suec. 1761. 144. 

 Oval, slightly oblong, moderately convex. Head and thorax piceous or 



lilack, shining; elytra usually reddish with a triangular piceous space ex- 

 tending from base one-half or more to apex and a subhumeral stripe pic- 



