316 CHARLES ROBERTSON. 



third aud fourth with a little bluish reflection ; wings hyaline, uervures fuscous; 

 tegulse black, with a testaceous spot; hindmost tibial spur long, thickly set with 

 fine teeth. Length 8 mm. 



Hab. — Illinois; one specimen. 



Halictus ueluiiibonis 9 .— Black ; clypeus slightly produced ; raesotho- 

 rax thinly clothed with blackish pubescence, coarsely aud densely punctured, 

 the punctures confluent into coarse reticulations on the sides; scutellum more 

 finely punctured ; metathorax hardly truncate, clothed with long, feathery hairs, 

 the surface obscured by a sericeous tomentum, the disc bearing a triangular en- 

 closure, which is rugose and shining, in strong contrast with the hairy portion ; 

 abdomen shining, impunctate, segments 2 and 3 with faint indications of inter- 

 rupted basal fasciae of pale pubescence ; wings hyaline, or a little clouded, ner- 

 vures fuscous; tegulse black, punctate; posterior tibial spur with four or five 

 teeth, the basal ones longest. Length 7 — 8 mm. 



% . — Closely resembles the female; antennae hardly longer; mandibles, except 

 tips, testaceous; labrum emarginate ; abdomen, impunctate tegulse and legs, in- 

 clining to brownish. Length 6 — 7 mm. 



Hab. — District Columbia, Florida. Illinois, Wisconsin (Trelease) ; 

 thirty-four 9 » two % specimens. 



This bee prefers flowers of Nymphceacece, which seems to account 

 for its being overlooked. I have taken it on flowers of Nuphar, 

 Nymphcea and Nelumbo, in Illinois, and on Nuphar and Nymphoia in 

 Florida. Prof Trelease found it on Nuphar in Wisconsin. The 

 American Entomological Society's collection contained only the two 

 males from District of Columbia. 



Halictiis 4-inaciiIatus 9- — Black, shining; head broad, eyes promi- 

 nent, clypeus hardly produced ; mesothorax finely and rather sparsely punctured ; 

 .scutellum sparsely punctured ; metathorax rounded, the disc short, sloping, with 

 longitudinal rugae at base, smooth beyond : abdomen impunctate, bases of seg- 

 ments 2 and 3 with a patch of appressed white pubescence on each extreme side; 

 wings hyaline, nervures fuscous, or dull honey-yellow, second cubital cell strongly 

 narrowing to the marginal, the first recurrent nervure commonly uniting with 

 the second transverse cubital ; tegulap more or less testaceous ; posterior tibial 

 spur with four or five long teeth. Length 5 — 6 mm. 



% . — Eesembles the female; form not slender; head large; antennae little lon- 

 ger than in female; metathorax a little rougher; clypeus anteriorly, labrum, 

 mandibles, except tips, tegulse, tibiae, except a patch above and beneath, and 

 tarsi, pale whitish, or testaceous. Length 5 mm. 



Hah. — Connecticut (Patton), Tennessee (i\.aron ), Illinois ; fourteen 

 9 , one % specimen. The female is apt to be confused with that of 

 H. gracilis, but may be distinguished by the descriptions. 



.Halictus gracilis 9 ■ — Black, opaque ; clypeus produced ; mesothorax 

 closely and minutely punctured; metathorax hardly truncate; the disc with 

 irregular longitudinal striae, sometimes uniting in coarse reticulations, at apex 



