psilopus. 251 



rery rough fringe ; towards the end of the joint they are decreasing 

 in length, and can hardly be distinguished at the end. The hind 

 tarsi of the only specimen which I possess, seem to be somewhat 

 shorter than those of a male of P. sipho of the same size. In all 

 other characters the agreement is complete. 

 Hab. Pennsylvania. (Yon Ileyden.) 



4. P. patitoulatlis Say. % and 9 . — Obscure viridis, nitidus, alarum 



fasciis duabus nigris, antice coujunctis et postice abbreviatis, facie 



pilosa, pedibus nigris. 

 £ . Halteribus nigris, prime- tarsorum anticorum articulo elongato et api- 



cem versus in latere exteriore setis nigris armato, articulis duobus 



sequentibus brevissimis. 

 9 . Halterum capitulo flavo. 



Dark-green, sliining ; wings with two black bands, wbicli are connected 



in front and shortened behind ; face hairy ; feet black. 

 $ . Halteres black, the first joint of the fore tarsi elongated, and towards 



the tip, upon the outside, beset with black bristles, the two following 



joints extremely short. 

 9 . Knob of the halteres yellow. Long. corp. 0.20—0.23. Long. al. 0.20 



—0.23. 



Syn. Dolichopus patibulatus Say, Journ. Ac. Philad. Ill, 87, 7. 

 Psilopus patibulatus Say, Journ. Ac. Philad. VI, 168, 2. 

 Psilopus patibulatus Wiedemann, Auss. Zweifl. II, 225, 27. 

 Psilopus amatus Walker, List, etc. Ill, 648. 

 Psilopus injicitus Walker, List, etc. Ill, 649. 

 Psilopus patibulatus Loew, Neue Beitr. VIII, 85, 3. 



Male. Bright, shining, dark-green, often steel-blue, particu- 

 larly the head, the posterior part of the thorax, the scutellum ami 

 also the front and hind segments of the abdomen. Proboscis and 

 palpi black. Face beset with long whitish or pale fallow-yellow- 

 ish hairs, but little dusted. Second joint of the antenna; with 

 rather long bristles, the third joint small and rather rounded. 

 Arista distinctly dorsal, of moderate length. Front at the upper 

 eye-corner with a long, black pubescence. Upper side of the thorax 

 and the scutellum with long black bristles. Pleurae black with n 

 green reflection and slightly dusted with white, which gives them 

 a somewhat grayish appearance. Abdomen shining green, the 

 first segments often, the two last generally, purplish-bine ; on the 

 anterior margin of the single segments there are black, not very 



