AMERICAN HYMENOPTERA. 189 



4. improvisus, Cress. Trans. Am. Ent. Soc. i, p. 29fi, % . 



Ilab. — Can., N. J. A dull black species, with white annulus on 

 antenna), and the two or three apical segments of abdomen marked 

 with white J the face except median black stripe, scutellura, most of 

 four anterior tibia? and tarsi and base of posterior tibi:«, are also 

 white; wings dusky; the second and third ventral segments have 

 generally a distinct longitudinal fold, which sometimes extends on 

 half of fourth segment. Length % .60 — .65 inch. 



This is probably the % of tetricus. 



5. perluctuosus, Prov. Nat. Can. ix, p. 10, 9 (not % ). 



Hab. — Can., N. II., Van. An elongate, rather narrow, deep black 

 species, with slender antennae, subhyaline wings, and lateral margin 

 of face, broad annulus on antennte, line before tegulae, short one 

 beneath, scutellum and annulus on all the tibia;, white. Length 9 

 .55— .60 inch. 



6. expunctus, Cress. Trans. Am. Ent. Soc. i, p. 290. 



obliterafiis, Cress, (nee Weam.) Proc. Ent. Soc. Phil, iii, p. 147, % . 

 Ilab. — Colorado. This is a deep black species, with dot on tegulae, 

 a short line in front, another beneath, scutellura, line on whole length 

 of four anterior tibi<ic and short line at base of posterior tibiae, white; 

 wings dusky at tips; head and antennae entirely black; an imper- 

 fectly formed longitudinal fold on second ventral segment. Length 

 S .55 inch. 



7. ultus, Cress. Trans. Am. Ent. Soc. i, p. 295, % . 



var. rogalis^ Cress, id. p. 295, % . 

 Hab. — Can., N. Y., Ct., W. Va. A dull black species, with face 

 and clypeus more or less, scape beneath, tegula;, short line in front, 

 another beneath, scutellum, spot behind, all the coxae more or less, 

 stripe on four anterior femora within, knees, their tibiae and tarsi and 

 posterior tibiae except tips, white; wings hyaline; sometimes the pos- 

 terior tarsi are more or less white and one specimen has the posterior 

 tibiae entirely black except a short white line near base; ventral 

 segments flat, .smooth and polished, in one specimen only the second 

 and third segments have each a longitudinal fold. Length % .60 — 

 .70 inch. 



8. stadaconensis, Prov. Nat. Can. vii, p. 50, % . 



Ilab. — Can., N. II., Mass. This differs from ultus principally by 

 the abdomen being strongly tinged with blue, the second and third 

 segments of which are coarsely and longitudinally sculptured at base; 



