THE SHORT-WINGED SCAVENGER BEETLES. 479 



KEY TO INDIANA SPECIES OF OLOPHKUM. 



a. Thorax twice as wide as long, sides broadly rounded into base and 

 apex; length 5-6 mm. 923. OBTECTUM. 



aa. Thorax subquadrate, sides snbparallel, the front angles obliquely trun- 

 cate; length 4.5-5 mm. ROTUNDICOLLE. 



923 (2828). OLOPIIRUM OBTECTUM Eriohs., Gen. Spec. Staph., 1840, 865. 



Oblong-oval, convex. Uniform piceous, shining; antennae, legs and very 

 narrow margin of thorax reddish-brown. Head rather coarsely and closely 

 punctate, with two shallow triangular impressions on vertex. Thorax 

 coarsely, evenly, not densely punctate, often with a faint rounded impres- 

 sion at middle of base. Elytra scarcely wider and nearly three times longer 

 than thorax, densely, rather coarsely and evenly punctate. Abdomen smooth, 

 its apex paler. Length 5-6 rnm. 



Throughout the State; common. April 7-November 28. Oc- 

 curs on fungi and beneath bark and leaves. 



0. rotundicolle Sahib., is a boreal species reported from Cin- 

 cinnati. 



Pycnoglypta lurida Gyll., oblong, convex, brownish- 

 piceous, 2.8 mm. in length, is also recorded from the 

 same locality. 



LXXXIII. HOMALIUM Grav. 1802. (Gr., "even or 



smooth.") 



. Fig. 170. Homalium 



(small elongate or oblong, subdepressed species (Fig. diffusum Fauv. xio. 

 Ir7n , , . . . < i i n A Lake Superior spe- 



li 0), having the joints ot hind tarsi very short and des. 



equal, tibiae with fine spines ; maxillary palpi with last joint longer 

 than third ; elytra reaching to or beyond the middle of abdomen. 

 The following have been taken or perhaps occur in Indiana. 



KEY TO INDIANA SPECIES OF HOMALIUM. 



a. Thorax even, or sometimes with two more or less obsolete impressions 



on the disk. 

 1). Sides of thorax not angulate at middle. 



c. Thorax very even, strongly convex ; length 2.3 mm. 924. HAMATUM. 

 cc. Thorax with a faint impression each side of disk. 

 d. Elytra convex. 



c. Smaller, 3 mm.; black or piceous; abdomen almost smooth; 



elytra not striolate. HUMEROSUM. 



ec. Larger, 4 mm. ; reddish-brown ; abdomen strongly and densely 



punctate ; elytra striolate. PUNCTIVENTRE. 



dd. Elytra subdepressed ; thorax short, hind angles obtuse. 



925. FLORALE. 



&6. Sides of thorax angulate at middle; head and thorax shining, dis- 

 tinctly punctate. 926. FRACTUM. 

 aa. Thorax uneven, the disk with two distinct fovere. 

 [3123402] 



