THE LAMELTjICORN BEETLES. 



975 



c. Form more or iess ovate; front without erect hairs; lasl ventral of 

 male convex; fifth ventral concave, with a short oblique ridge each 

 si( j ei 1827. IMPLICITA. 



cc. Form more elongate, parallel; front with erect hairs. 



d. Last segment of male with a cup-shaped impression ; clypeus broad- 

 ly not deeply emarginate; pubic process of female slender and 

 bifid at tip. 1828. balia. 



dd, Last segment of male broadly and shallowly concave, with a longi- 

 tudinal impression at middle; clypeus deeply emarginate; pubic 

 process of female bifid but short, broad and stout. 



1829. VILLIFRONS. 



L. Urmia Knoch, reddish-brown to piceous, length 15-18 mm., 

 and L. longispina Smith, reddish-brown, margins of thorax crenu- 

 late, length 17 mm., are both known from Michigan. 



1S27 (10,255). Lachnosterna implicita Horn, Trans. Ainer. Entom. Soc, 

 XIV, 1887, 262. 



Oblong-oval, moderately robust. Elytra brown, head and thorax always 

 darker, more nearly piceous, body beneath paler than above. Clypeus rather 

 deeply and acutely emarginate, its surface closely and rather coarsely punc- 

 tate. Thorax widest at middle, the margin feebly cremate, with short cilise; 

 surface coarsely and regularly but not closely punctate, the median line 

 usually smoother." Punctures of elytra more shallow and dense than those 

 of thorax, somewhat rugose; coshe feeble, the submarginal more distinct. 

 Male with antennal club longer than stem ; ventral characters as given in 

 key. Length 14-17 mm. (PL IV, fig. 396.) 



Southern half of State, frequent ; Lake County, rare. May 6- 

 June 9. Occurs abundantly at electric light in Vigo County. 

 Readily distinguished from the next two by the broader form, 

 difference in color and convex last ventral segment of male. 



1828 (5782). Lachnosterna balia Say, Journ. Phil. Acad. Nat. Sci., V, 

 1825, 194; ibid. II, 297. 

 Oblong, slightly broader behind. Chestnut brown, moderately shining. 

 Head coarsely and rather densely punctured ; front convex, with erect hairs. 

 Thorax narrowed in front, widest at middle, very slightly narrowed behind, 

 margin entire with rather long cilia?; surface coarsely, not closely and some- 

 what irregularly punctured, usually with a smooth median space. Elytra 

 more finely and rather densely and roughly punctured. Male with club of 

 antenna? as long as stem ; abdomen broadly flattened at middle, the fifth 

 segment with a curved transverse elevation in front of a slight concavity. 

 Length 15-16 mm. (PI. II, fig. 384.) 



Southern and western portions of the State north to Fountain 

 County ; frequent. April 18-May 27. Occurs beneath leaves along 

 the borders of woods and also at electric light, 



[62—23402] 



