204 Oi'thoriliapha Inachycera. 



varies very niuch, and it has therefore been divided into several 

 species, which were generally foimded only on one of the sexes. 

 Sufficient account of its synonymy is given by Stæger (Krøyer's Tidsskr. 

 IV, 1842—43, 98) and in the Kat. palåarkt. Dipt. The single sex does 

 not vary so much, and each sex has its own varieties; the female is, 

 even in its darkest forms, always paler than the male; the darkest 

 variety of the male (melanopleura), and the pale form of the female 

 {glahricula) are most coramon. The different varieties, which are, for 

 the rest, connected by transitions, are not easily determined by use 

 of the literature, because the earlier writers generally did not note 

 the sex. To be sure Meigen does so for some of his species, but this 

 is, as already noted by Stæger 1, c, erroneous, and Meigen's species 

 are, in spite of his statements, always founded only on one sex; as 

 the exterior sexual difference is only small, Meigen has evidently had 

 no clear idea of the sexes. Fallen on the other hånd has identifled 

 the two sexes of the species correctly. Schiner gives a good account 

 of the varieties, but the sexes are intermingled ; thus he says of var. 

 (jlahricula, that the abdomen is thick and compressed ; this is because 

 the variety comprises only the female. Strobl (Mittheil. Ver. Steierm. 

 1892, 94) divides the forms into three varieties, and says that all 

 varieties occur in both sexes, but this is certainly not correct. 



O. glahricula is a common species in Denmark; at Copenhagen 

 in gardens. Lersøen, Ermelund, Geel Skov, Boserup at Roskilde, Tis- 

 vilde, Frederikssund; on Langeland at Lohals; on Funen at Odense, 

 Veflinge and Strib; in Jutland in Greisdalen at Vejle, at Nebsager 

 near Horsens, Hald near Viborg and Frederikshavn; finally on Born- 

 holm at Rø. It is found during the whole summer, my dates are 

 is<;(5 — o/c, It occurs especially on humid, somewhat shaded piaces in 

 woods, and on meadows, often in great numbers; it is seen hovering 

 slowly and somewhat low, or sitting in the herbage. 



Geographical distribution: — Europe down into Italy; towards 

 the north to northern Scandinavia, and in Finland. It occurs also in 

 North America. It is thus a widely distributed, and everywhere rather 

 common species, 



11. Leptopeza Macq, 



(1S127. Lemtopeza). 

 Species of somewhat small size, and of black or yellow colours, 

 The head is globular, almost as broad as thorax, arched behind, 

 Occiput haired. Eyes large, occupying the whole front side of the 

 head ; they are touching in both sexes or {spJieyioptera) very narrowly 

 separated in both sexes, but in the latter case on the other hånd touching 



