f)F NATLRAL IIISTORY. 717 



of the thighs, the scutfl diffi-rs iVniii that of tlie iiroi-eJinj; fju- 

 c'ies in being rugose, or with about tivc clevatfd lint's, and it« ter- 

 minal spine is much broader at the base and less eouic. 



.'). 1). IMI'ATIKNS. — Black: Icet ferruginous : scutcl inutic. 



Inhabits Indiana. 



Body black, polished, obsolctely tinted with piit<iu> : antomia' 

 piecous-blackish : mandibles Icrruginous : scutel with tin; mar. 

 gin deeply depressed and rugose : the disk elevated, i»val, with 

 an acute edge, within which, on the posterior half, is an indenta- 

 tion and a more slight indentation before it, each siile of which 

 are two or three punctures : wings hyaline, nervures pale brown : 

 abdomen acute at the tip of the tergum : feet ferruginous ur rather 

 piceous. 



Length tliree-twentieths of an inch. 



4. 1>. I'F.PATl'S. — Black: feet yellowish: aiittiiri:e piccdu." : 

 third joint long. 



Inhabits Indiana. 



Body jmlished, impunctured, black: antennajyellnwish-piceous : 

 first joint nt)t much longer than the second : third joint much 

 longest, ecjual to the fourth and fifth together, and a little arcu- 

 ated : remaining joints sube«jual, [268] oval-cylimlric : nasiLs 

 with a longitudinal indentation each side before : mandibles pi- 

 ceous : thorax without dorsal grooves, but a simple one over th« 

 wings : wings with a very slight obscure tint : nervure.s brown : 

 feet boney-yellow. 



Length % less than one-twelfth of an inch. 

 Differs from the two preceding .species by the elongated third 

 joint of the antenna?. 



'>. I). STKi.MATUS. — Black : feet yellowish : wings with a large 

 ^tigma. 



Inhabit,s Indiana. 



Body polished, black : antennaJ piceous: basal joint yellow- 

 ish : second joint closely [united to the first, shortest, almost 

 epherical : second and third joints subcqual : wings hyaline, 

 nervures yellowish : stigma large, triangular : abdomen dull ru- 

 fous : feet pale honey-yellow. 



Lenffth about one-twentieth of an inch. 



1835.] 



