A Monograph of Egyptian Diptera. 39 



dark specimens may have orange tarsi and pale specimens dark 

 tarsi. The pubescence on the front femora is either entirely yellow 

 or with the minute hairs black below; behind the middle femora 

 the pubescence is longer and black from the trochanters to the 

 end of the tarsi; except on the inside of the hind tibiae on the 

 apical half. 



Wings rather greyish, pellucid, with the extreme base 

 orange and the stigma yellowish-brown. Squamulae with their 

 margins and fringes yellowish. Halteres pale yellow. 



Female, (PI. Ill, fig. 8), Rather similar to the male except for the 

 shape and markings of the abdomen. The f rons is moderately broad 

 at the vertex and very shining aeneous for the entire width of the 

 upper half, which is continued on about the middle third almost 

 to the antennae; its pubescence is short, inconspicuous and fol- 

 lows the ground colour. 



Abdomen more even in shape, less clubbed and not so con- 

 stricted about the middle. The orange markings on the segments 

 are very variable; the side margins of the first segment are yel- 

 low and those of the second segment are very similar to those 

 in the male but rather broader and sometimes interrupted; the 

 band on the third segment is also either entire or interrupted, and 

 arched from near the hind margin at the sides, to near the front 

 margin in the middle; the band on the fourth segment is similar 

 but broader and hence occupies more of the segment and when it 

 is interrupted in the middle it has small projections near the 

 middle, both above and below ; on the fifth segment the band has 

 these projections increased so that the segment is all orange ex- 

 cept for a black dorsal line, the basal corners, and the two large 

 corners of the hind margin; the sixth segment is entirely orange 

 except for a broad black dorsal line and two round brownish-black 

 spots on the sides and at the end of the dorsal line. Pubescence 

 also pale about the basal corners and about the sides down to the 

 end of the third segment ; below this it is longer than in the male 

 and entirely blackish. 



Length from 8 to G mm. 



Var. calceolata Macq., (Pl.III, fig.10), I do not consider this to be 

 anything but a dark variety of the above species in which the femora 

 are considerably darker and the abdomen with the orange markings 

 less extensive, thus leaving the abdomen darker but with the 

 orange markings also greatly varying in almost every individual. 

 This variety seems to correspond almost exactly with the European 

 var. nitidicollis Zett. of S. flavicauda. In some of my specimens 

 the abdominal markings of the male run together, i.e* the orange 



