192 E. T. CRESSON. 



line before, one beneath, scutellum, spot behind, spot on disc of meta- 

 thorax, spot on all the coxae, four anterior legs mostly, posterior tibiae 

 except tips, and sometimes their tarsi entirely, whitish; wings clear; 

 the second and sometimes the third ventral segments have a lonjii- 

 tudinal fold. Length % .60 inch. 



21. Nortoni, Cress. Trans. Am. Ent. Soc. i, p. 304, 9 . 



Mab. — Connecticut. A rather slender black species, with abdomi- 

 nal segments two to four entirely, and apex of one, ferruginous; dot 

 on each side of ocelli, annulus on antennae, scutellum and two spots 

 at tip of abdomen, yellowish-white; wings hyaline; antennae and legs 

 slender; head broader than usual. Length 9 •'i^ inch. 



22. detritus, Brulle, Hym. p. 302. 



S^j'hax, Cress. Proc. Ent. Soc. Phil, iii, p. 181, 9 . 

 Hab.— Can., Me., Mass., N. Y., Pa., N. J., Del. This is a black 

 species, with the abdomen, except first segment, ferruginous; the 

 antennae are slender, with a broad white annulus on each, the third 

 joint is longer than the fourth; the wings vary from subhyaline to 

 dark fuliginous; the scutellum has occasionally a white spot; post- 

 petiole finely aciculated. Length 9 .50 — .60 inch. 



23. semicseruleus, Cress. Trans. Am. Ent Soc. i, p. 302, 9 . 

 Hub. — Can., N. H., W. Ya. Distinguished at once from detritus 



by the beautiful steel-blue head and thorax and clear wings; the 

 scutellum is more or less white. Length 9 ,50 inch. 



24. indistinctus, Prov. Nat. Can. vii, p. 75, 9 . 



Hab. — Can., N. H., Mass., Ga. This is colored exactly like detritus, 

 but is easily separated by the scabrous postpetiole, and by the third 

 and fourth joints of antennae being equal in length; the scutellum has 

 frequently a pale spot. Length 9 .50 — .55 inch. 



25. hudsonicus, n. sp. 



9 . — Black ; anterior orbits, broad on face, mandibles, scape beneath, tegulse, 

 legs except coxaj and base of trochanters, and abdomen except first segment, 

 ferruginous; wings fuliginous; third joint of antennae longer than fourth ; post- 

 petiole finely aciculated ; gastrocoeli small, foveiform. Length .52 inch. 



ffab. — Iludsons Bay Territory. 



26. fraternus, n. sp. 



% . — Black ; face, clypeus, scape beneath, four anterior legs except coxae, 

 trochanters and their femora behind, posterior tibiae except tips, and their 

 tarsi, yellow; wings yellowish-hyaline; abdomen except first segment fer- 

 ruginous. Length .70 inch. 



Hab. — Mass., Ya. Yery much like niibivagus, but at once sepa- 

 rated by the black scutellum. 



