304 E. T. CKESSON. 



I. electus. — %. Black; faoo wliite, with a median black sjiot or line on the 

 sutures; clypeus entirely white or with two white spots; jialpi pale, black at 

 base; antennae long, slender, much attenuated at tips, serrate, black, the basal 

 joint white beneath; tegulse, a sutural line before and a short line beneath, scu- 

 tellurn and post-scutellum white; in one specimen the posterior margin of the 

 central area of metathorax is white; wings hyaline, nervures black ; legs black, 

 varied with white; in one specimen all the coxte are white, black at base be- 

 neath; in the other specimen they are black, the two anterior pah's spotted be- 

 neath with white; anterior femora in front, the four anterior tibiee and tarsi, 

 the posterior tibia;, except tips, and their tarsi more or less, also white; in one 

 specimen the intermediate tibiae has a white line beneath; abdomen with the 

 second, third and base and sides of fourth segments bright yellowish-ferrugi- 

 nous. Length 6 — -74 lines. 



Hab. — •Connecticut, (('ull. Mr. E. Norton). Two % specimens. 



I. volesus. — 9. Robust, dull black, head and sides of thorax shining, head 

 not narrow beneath; antennas with a white annulus about the middle; scutel- 

 lum polished, metathorax rugulosc, central area oblong-quadrate, posterior an- 

 gles prominent cariniform ; tegukc dull ferruginous; wings pale fusco-hyaline, 

 nervures brown, stigma fulvous; legs black, tips of anterior femora, their tibiae 

 and tarsi, most of the middle tibiae and tarsi, and the basal two-thirds of the 

 posterior tibiie ferrugiuous, their tarsi brown; abdomen robust, ovate, black, 

 second and third segments entirely ferruginous, two a]iical segments with a 

 central white spot, beneath as above, excejit that the apical white sjiots arc 

 wanting. Length lines. 



Jfab. — Massachusetts, (J. Ridings.) One 9 specimen. 



I. Nortonii. — 9- Black, thinly pubescent, head broad, slightly narrowed be- 

 neath, eyes large and prominent; a white spot on each side of the vertex ou 

 the anterior orbits; antenutc long and unusually slender, especially at tij)^ 

 black, with a white annulus about the middle, basal joints of flagellum long and 

 subequal; two sjiots on the collar, a spot before tegulaj and another b'neath, 

 and the scutelluin except tip, white; a ferruginous spot on the post-scutellum: 

 metathorax densely and confluently punctured, the elevated lines well defined, 

 the central area elongate, subquadrate; wings subhyaline, dusky at tips, ner- 

 vures brown, stigma yellow, areoleto-angular; legs slender, black, thinly pubes- 

 sent, ti])s of four anterior femora, their tibiaj and tarsi, and basal half of poste- 

 rior tibise rufo-testaceous; abdomen subdepressed, narrow, ferruginous; first 

 segment black at base, slender, dilated and depressed at tip, which is smooth 

 and shining above, basal fovese of second segment very deep; the fifth and fol- 

 lowing segments black, the two last tipped with white.. Length 5i lines. 



JIab. — Connecticut, (Coll. Mr. E. Norton). One 9 specimen. A very pretty 

 and distinct species. 



I. finitimus. — 9- H'^a'l black, sides of the face, clypeus, most of the mandi- 

 ]>les and the palpi white; one specimen has the face white, exce])t a small black 

 central sp<5t; antennae long, slender, black, with a white annulus beyond the 

 middle, at base beneath the joints are reddish; thorax black, sometimes brown- 

 isii ; the metathorax, except sometimes its lateral margin, and more or less of 

 the pleura ferruginous; metathorax excavated behind, with a short, blunt, pro- 

 minent spine on each side, the elevated lines well defined, the central area 

 quadrate, rather large; teguhe, scutellum and post-scutellum white; wings hya- 



