254 E. T. CRESSON. 



Ilaliftiis coactns, n. sp. 



J. — Green, abdomen dark seneous, clothed with a short pale pubescence ; 

 head very densely and finely punctured; elypeus slightly produced, with 

 large sparse punctures, apex broadly purplish and fringed with long yellow 

 hairs; flagellum pale brown beneath, especially at tips; mandibles tipped 

 with ferruginous; thorax much less closely punctured than the head : base of 

 inetathorax finely, somewhat longitudinally, rugose; tegula? brown; wings 

 hyaline, iridescent, nervures and stigma pale honey-yellow; legs brown-black, 

 clothed with pale pubescence; abdomen ovate, convex, very minutely punc- 

 tured, sides and apex thickly clothed with short pale pubescence, apical mar- 

 gin of first and second segments deeply impressed or constricted, especially 

 that of first segment. Length .20 inch. 



Four specimens. (Belfrage.) Easily recognized by the constricted 

 segments of abdomen. 

 Halictus si 11 II us. n. sp. 



2- — Small, head and thorax dull dark green, sometimes tinged with 

 brassy, thinly clothed with a short griseous pubescence; head not broader than 

 thorax, closely and minutely punctured, face broad, elypeus short, sparsely 

 punctured, purplish-black towards apex which is fringed with long pale yel- 

 lowish hairs; mandibles piceous, sometimes tinged with rufous; antenna? 

 short, black, flagellum more or less pale beneath towards apex; mesothorax 

 very minutely and sparsely punctured, sometimes almost imperceptably so, a 

 deeply impressed central longitudinal line; scutellum slightly impressed cen- 

 trally ; base of metathorax with radiating elevated lines which are sometimes 

 more or less abbreviated; on postscutellum, sides of metathorax and pleura 

 the pubescence is longer than elsewhere; tegula? testaceous; wings hyaline, 

 iridescent, nervures and stigma pale testaceous; legs pale brown or fuscous, 

 blackish at base, clothed with pale pubescence, anterior knees and all the tarsi 

 rufo-testaceous; abdomen smooth and shining, impunetured, more or less 

 thickly pubescent towards apex, the base and sides thinly pubescent, color 

 variable, being sometimes entirely brown-black, sometimes fuscous with the 

 segments testaceous at apex, sometimes more or less testaceous at base, 

 shading into brown or fuscous at apex, sometimes entirely testaceous or dull 

 honey-yellow. Length .16 — .20 inch. 



Ten specimens. (Belfrage.) 



Halictus albitarsis, n. sp. 



% . — Dark bronzed-green, sometimes slightly brassy, clothed with a whitish 

 pubescence; head not broader than thorax, densely and finely punctured, 

 sides of face and elypeus densely clothed with an appressed silvery-white 

 pile; mandibles piceous; antenna? long, black above, brown or pale fuscous 

 beneath; mesothorax and scutellum with sparse minute punctures and gener- 

 ally with a distinct impressed longitudinal line on disk and over tegula?; pu- 

 bescence of thorax above erect, longer on postscutellum, sides of metathorax 

 and pleura; metathorax generally tinged with blue, the base more or less 

 longitudinally rugose, sometimes with well-defined and distinct radiating ele- 

 vated lines or wrinkles; sides of metathorax and pleura finely roughened; 

 tegula? testaceous, sometime dull; wings hyaline, iridescent, nervures and 

 stigma pale testaceous ; legs black or piceous, shining, clothed with pale pubes- 



