516 Coleopterological Notices, V. 



Scutellum minute but distinctly advanced between the elytra. 



Larger ; basal stria of the elytra entire ; third antennal joint as long as the 



fourth texaiia 



Minute species ; basal stria interrupted ; third antennal joint much shorter 

 than the fourth. 

 Basal angles of the prothorax acute ; met-episternum narrow ; color pice- 



ous-brown picea. 



Basal angles produced but truncate at apex ; met-episternum broad, the 

 suture arcuate; body intense black nana 



B. concolor Fab. — Syst. El., II, p. 576 (Scaphidiura). 



Oblong-oval, broad, strongly convex, highly polished, subgla- 

 brous, very sparsely and obsoletely punctulate throughout, black ; 

 legs, antennae and abdominal vertex more or less paler, rufo-piceous. 

 Head vertical ; eyes large ; antennae widely separated, very slender, 

 not as long as the head and prothorax, the third joint fully five 

 times as long as wide, very slightly shorter than the fourth, both 

 shorter than the fifth, which is fully seven times as long as wide, 

 seventh shorter than the sixth, eighth still shorter, seventh and 

 eighth but slightly thicker, ninth longer than the tenth but shorter 

 than the eleventh. Prothorax short, three-fourths wider than long, 

 the apex one-third as wide as the base ; side margin, viewed later- 

 ally, evenly, moderately arcuate. Scutellum wanting. Elytra barely 

 as long as wide, scarcely twice as long as the prothorax, somewhat 

 wider between basal third and fourth than at base, unusually broadly 

 truncate at apex. Mes-epimera extending fully two-thirds to the 

 coxag ; met-episterna between three and four times as long as wide, 

 parallel, the suture coarse and deep. Posterior tarsi scarcely more 

 than two-thirds as long as the tibiae, the first joint fully as long as 

 the next three. Length 2.7 mm.; width 1.6-1.7 mm. 



Pennsylvania to Illinois. This is the largest known species 

 within our boundaries, and may be known by its broadly sub- 

 oblong-oval form. The description is taken from the female, the 

 fifth ventral plate being broadly, feebly lobed in the middle, the 

 sixth strongly produced in a more narrowly rounded lobe, the 

 sides of the lobe feebly, evenly sinuato-oblique. In the male the 

 fifth is broadly, feebly bisinuate toward the middle, the sixth ab- 

 ruptly produced in the middle in a short, gradually narrowed, 

 narrowly rounded ligula, as long as wide, flanked on either side 

 by a small but deep rounded eniargination. There appears to be 

 scarcely any sexual divergence in antennal structure. Three speci- 

 mens, remarkably uniform in size. 



