161 



distinct ; wings large, hyaline ; stigma, and costa pale-luteous. Hab. 

 Mass., (H. CoU.) 



Two specimens. This resembles iV. proximus of Europe. 



13. N. OBSCURUS, (n. sp.) Dull black; tegulae, base of abdomen 

 and knees, indistinctly ferruginous. (Long. 0.25, Ex. alar. 0.58 in.) 



? . Dull black, pubescent ; third joint of antennae but little longer 

 than fourth and fifth ; clypeus crenate, labrum brownish-red, shining ; 

 mandibles rufous at tip ; palpi pale ; a longitudinal suture upon scutel- 

 lum ; basal membrane, sides of tergum, knees and front of tibia?, in- 

 distinctly ferruginous ; abdomen stout ; wings faintly clouded ; stigma 

 dull fuscous ; costa black. Hab. Mass., (H. Coll.) 



One specimen. The wings are cj^uite long and broad. 



14. N. LUTEOTERGUM. Black ; antennae long ; abdomen and legs 

 honey-yellow. (Long. 0.20, Ex. alar. 0.43 in.) 



$ . Color black ; antennae long and slender ; third, fourth, and 

 fifth joints of equal length ; a W-shaped depression, half inclosing 

 the upper ocelli; clypeus slightly emarginate; labrum rounded, 

 smooth, and shining ; edge of clypeus, labrum, and base of mandibles 

 pale-yellow ; palpi fuscous ; basal membrane, abdomen, and legs 

 honey-yellow ; four anterior femora at base, posterior femora, except 

 at tip, posterior tibiae, except at base, and the tarsi blackish ; wings 

 hyaline, stigma and costa pale. Hab. Maine, (H. Coll.) 



One specimen. Eesembles N. dimidlatus of Europe. 



15. N. MOxocHROMA. H. Cat. Honey-yellow, pleura piceous. 

 (Long. 0.30, Ex. alar. 0.60 in.) 



?. Color honey-yellow; (antennae wanting, except two basal 

 joints, which are color of body ;) ocelli black, set in an irregular de- 

 pression ; clypeus retracted, crenate ; labrum angulate, hairy ; face 

 immaculate ; tegulae, collar, venter, and coxae paler than body and 

 legs ; pleura dark, almost piceous ; wings hyaline, stigma and costa 

 pale-yellow. Hab. Mass., (H. Coll.) 



One specimen examined. It resembles N. luteus of Europe. 



16. N. STiGMATUS. H. Cat. Greenish-luteous ; thorax and tergum 

 black. (Long. 0.30, Ex. alar. 0.60 in.) 



? . Color greenish-luteous ; first two joints of antennae black ; an 

 irregular H-shaped sinus on vertex and occiput, inclosing ocelli ; a 

 small black spot about each of ocelli ; clypeus hardly emarginate ; 

 labrum angulate, hairy ; part of mesothorax, the metathorax, the first 

 seven segments of tergum and ovipositor, black ; a spot on first seg- 

 ment, the apex of seventh and apex of abdomen, color of body ; a 

 black spot on pleura, between wings ; nails and tips of tarsi dark ; 

 stigma and costa pale-green. Hab. Mass., (H. Coll.) 



One specimen. In form and general appearance it resembles N. 

 monochroma, and may prove to be a variety of it. 



PROCEEDINGS B. S. N. H.— VOL. VIII. 11 8EPTEMBEK, 1861. 



