THE GROUND BEETLES. 87 



an. Terminal joint of palpi slender, acute at tip, that of the labial palpi 



shorter than the preceding. 



h. Head with distinct eyes. XXI. TRECHUS. 



1>1>. Head without eyes. XXII. ANOPHTHALMUS. 



XX. PATROBUS Dej., 1825. 



Beetles of medium size, 10 or more mm. in length, having the 

 elytra elongate, not margined at base, their sides subparallel. For 

 literature regarding this and the next genus see : 



Horn. 11 Synoptic Tables" in Trans. Amer. Ent. Soc., V, 1874, 

 130; also in Bull. Brook. Ent. Soc., V, 1882, 47, 48. 



Seven species are known from the United States, one of which 

 occurs in Indiana. 



*116 (472). PATROBUS LONGICORNIS Say, Trans. Amer. 



Phil. Soc., II. 1823, 40; ibid. II, 466. 



Elongate-oval. Black above, piceous beneath; antenna? ** 

 reddish-brown, half as long as body; legs paler. Last 

 two joints of maxillary palpi equal. Thorax convex, a 

 little broader than long; sides curved to behind middle, 

 thence sinuate to base ; front transverse impression and 

 median impressed line deep, hind angles rectangular; 

 basal impressions broad, deep, punctured. Elytral stria? 

 deep and distinctly punctured ; intervals convex on disk, 

 flattened on sides. Length 12-14 mm. (Fig. 55.) Fig. 55. (After Leng.) 



Throughout the State; common. January 1-December 25. Oc- 

 curs beneath stones and rubbish along streams, lakes, etc. ; hiber- 

 nates as imago. Most common in May. 



XXI. TRECHUS Clairv. 1SO. (Gr.. "a runner.") 



Elytra oblong-oval, almost twice as long as wide; front tibia? 

 slightly broader to tip, the emarginatiou extending nearly to the 

 middle of the tibia?; length less than 6 mm. Four species occur 

 in the northern and western parts of North America, one of which 

 extends down into northern Indiana. 



H7 (483). TRECHUS CHALYBEUS Dej., Spec. V, 1829, 17. 



Elongate-oval. Black or dark brown with a bluish gloss ; antenna? 

 and legs reddish-brown. Thorax subquadrate, one-third wider than long ; 

 sides curved to behind middle, thence oblique to base ; disk smooth, median 

 impressed line distinct, basal impressions deep, not punctate, hind angles 

 subrectaugular. Elytra oblong-oval, with four or tive dorsal stria?, the- 

 outer two very faint ; stria? finely punctate. Inner wings absent. Length 

 5 mm. 



Steuben County; rare. May 13. One specimen was taken from 

 beneath leaves in low moist woods on the eastern edge of Clear Lake. 



