70 Orthorrhapha In-achycera. 



the anterior femora are pale friiiged. In remipes the posterior femora 

 have longish, pale hairs below in the male, and hind femora a black 

 fringe in the apical part. Pennatus, caligatus and lineatocornis have 

 in the male a fringe of shorter, fine, pale hairs below the hind femora. 

 Fallent and Meigenii have somewhat longish, pale hairs below the 

 posterior femora towards the base in both sexes. 



A long, thin hair at the tip of the front tibiæ in the male: 

 7iitidus, griseipennis, longicornis, latilimhatus^ Unearis, notabilis. 



Obs. The bristles on the tibiæ afford to some degree specific 

 characters; they are placed in rows, but the single bristles are not 

 always placed exactly below each other; whether a row should be 

 termed f. inst. dorsal or antero-dorsal, anterior or antero-ventral etc. 

 is often a matter of judgment, and the same holds good for some 

 of the single bristles. In the following descriptions I have used the 

 terms in accordance with the position, in which the rows or single 

 bristles appeared to me to be placed or to come nearest, but it may 

 well be, that a row or a bristle, which is in one species termed f. 

 inst. antero-dorsal, is in reality answering to a row or bristle termed 

 in another species dorsal or anterior etc; I do not think however, 

 that any mistake may arise from this. 



:7 



1. D. stratus Meig. 



1824. Meig. Syst. Beschr. IV, 76, 3. — 1831. Stann. Isis 1831, 139, 

 33. — 1842. Zett. Dipt. Scand. II, 521, nota, et 1849. VIII, 3078, nota. 

 — 1862. Schin. F. A. 1, 213. — 1903. Kat. paliiarkt. Dipt. II, 295. 



Male. Vertex and frons green or bluish. Epistoma moderately 

 narrow and a little narrowed downwards, grey. Palpi greyish black. 

 Occiput green, slightly pruinose; postocular bristles black. Antennæ 

 black, the third joint a little elongated, triangularly ovate, pointed. 

 Thorax green, slightly brownish pruinose, not much shining; there is 

 a faint, brighter shining middle stripe. Scutellum finely pale-haired 

 at the margin; postscutellum grey pruinose. Pleura greenish, greyish 

 pruinose; propleura with fine, pale hairs and a black, prothoracic 

 bristle. Abdomen green, often with some bluish reflexes, finely whitish 

 pruinose, especially downwards; the hind margins of the segments 

 narrowly darkened; abdomen has short, black hairs, and a little longer 

 bristles at the hind margins of the segments. Venter greyish, slightly 

 pale-haired. Hypopygium black, somewhat pruinose; the eighth seg- 

 ment with black hairs; there are small, brownish posterior ventral 



