THE ANT-LOVING BEETLES. 311 



V. PILOPIUS Casey. 1897. 



Antennae approximate at base, clavate ; joints 2-4 of maxillary 

 palpi with long bristle-like appendages, the second joint bent and 

 clavate, the third transversely lunate ; abdomen with second and 

 third ventral* not much longer than fourth; first four visible 

 dorsals equal in length ; front femora with stiff, erect bristles, but 

 without spines. Two species are known from the State and another 

 probably occurs. 



KEY TO INDIANA SPECIES OF PILOPIUS. 



a. Pubescence rather sparse; last joint of antennae as long as the three 



preceding combined. 



It. Tenth antennal joint not at all longer than wide, the sixth joint as 

 long as fifth; body stout; elytra nearly as long as wide. 



594. LACUSTKIS. 

 &?). Tenth antennal joint distinctly longer than wide. 



c. Body stout, generally dark in color; abdomen always black or 

 blackish ; thorax feebly transverse, never more than one-half as 

 wide as elytra ; fifth antennal joint slightly longer than fourth. 



IOWENSIS. 



cc. Body narrower, pale in color throughout, the abdomen never black- 

 ish ; elytra nearly as long as wide, rather longer than head and 

 thorax combined. 595. ZIMMERMANNI. 



. Pubescence dense, shorter and more scale-like; last anteunal joint much 

 shorter than the three preceding combined ; elytra as long as head 

 and thorax. CONSOBRINUS. 



*594 ( -). PILOPIUS LACUSTRIS Casey, Ann. N. Y. Acad. Sci.. IX, 1897, 



619. 



Rather stout, subconvex. Dark reddish-brown ; elytra, antenna? and 

 legs paler. Head as wide as long; occiput with two large fovea? between 

 the eyes. Antenna 1 of male three-fourths the length of body, joints cylin- 

 drical, nearly equal; of female, shorter with' joints 7-10 short, transverse, 

 last joint shorter, oblong-<>val. Thorax wider than long, disk with an ob- 

 long median fovea at base, reaching almost to middle, and a smaller one 

 each side. Elytra slightly wider at base than thorax, thence gradually 

 widening to apex, each with a fine, entire sutural and median stria. Ab- 

 domen convex, margin broad, tip rounded. Length 1.8 mm. (Fig. 148, </.) 



Southern half of State: common. April 5-December 23. Oc- 

 curs beneath logs and bark; gregarious in winter. A number were 

 once swept from stems of blue-grass in May. Usually known as P. 

 piceus Lee., from which it is distinguished by its more elongate 

 and paler elytra and shorter tenth antennal joint. 



P. ion- en sis Casey, length 1.7 mm., wns described from Iowa. 

 595 (1873). PILOPIUS ZIMMERMANNI Lee.. Bost. Journ. Nat. Hist., VI, 1849, 79. 



Pale brownish-yellow, sparsely pubescent. Head with frontal groove 

 not reaching the oblong frontal fovea?; occiput elevated, its fovea? larger. 



