570 THEREVID^ 



until the one on the seventh segment can hardly be traced. Pubescence 

 suberect, dense, moderately long, and black on the dorsal part, but in the 

 English specimen broadly brownish yellow all about the sides of the second 

 to fifth segments and on the belly, though when seen from above the long 

 black pubescence forms conspicuous tufts at the sides of the three basal 

 segments and numerous black hairs are intermingled at the sides of the 

 fourth and fifth segments ; in a continental specimen the abdominal 

 pubescence is all black except for some brownish black pubescence about 

 the basal corners, and when seen sideways appears rather tufted down the 

 dorsal line because of the gaps caused by the bare hindmargins. Belly in 

 the English specimen ashy grey, with broad but rather obscure hindmarginal 

 hems on the second to fifth segments which unite with the dorsal hems, and 

 it bears long thin straggly dark yellowish brown pubescence on the second, 

 third, and fourth segments and partly blackish pubescence on the next three 

 segments, and all this pubescence is somewhat interrupted at the base of 

 each segment ; belly in a continental specimen dull black, with broad 

 conspicuous pale dull golden hindmarginal hems on the second to fourth 

 segments, a rather narrower hem on the fifth segment and a decidedly narrow 

 one on the sixth segment. Genitalia with the upper lamellae as usual, and 

 the inner ones as well as the underside shining reddish orange. 



Legs mainly black, but the tibiae reddish orange except at the tip of the 

 front pair and slightly at the tip of the middle pair, and the four basal joints 

 of the tarsi obscurely reddish orange except at their tips; trochanters 

 shining; femora with an ashy grey tinge. Pubescence on the coxse and 

 femora mainly greyish or brownish yellow, but blackish and dense behind 

 the anterior femora, while pale scaly pubescence is abundant all over the 

 hind femora except on the underside ; in a continental specimen all this 

 greyish yellow pubescence becomes greyish black ; coxae strongly spinose 

 especially on the front part of the front pair ; front femora with about two 

 strong black bristles beneath, middle pair with about five, and the hind pair 

 with about fifteen irregular ones (or fewer in a continental specimen). 



Wings in the English specimen rather smoky and without any distinct 

 cloudings, but in a continental specimen much darker with the stigma brown 

 and with a tendency towards cloudings at especially the dip of the discal 

 vein ; veins dark brownish in the English specimen, ,but the stigma, the 

 costal, subcostal, and stem of the postical, veins brownish orange ; fourth 

 hindmarginal cell closed. Squamse brownish orange, with thick darker 

 margins and brownish orange fringes. Halteres brownish black, but brownish 

 orange on the stem. 



V . As I am unable to be certain about the female I give Loew's description. 

 " Cinerascens, thoracis dorsum vittis tribus nigricantibus interjectis lineis 

 " cinerascentibus angustissimis parum conspicuis ; abdomen nigrum, segmentis 

 " postice albo-fasciatis, fasciis arcuatim excisis lateraliter valde dilatatis ; 

 " callus frontalis brevissimus ab ocellis separatus, antice distincte emarginatus ; 

 " alarum nervi transversi fuscedine distinctissime marginati." 



Face whitish with whitish pubescence, and a clump of black hairs at the 

 lower eye-angles ; back of the head dirty whitish haired. Antennae black. 

 Frons yellowish, beset with fairly dense black hairs, which extend downwards 

 in a small degree on the eyemargins. Frontal callus very short, almost like 

 a cross-band, in front not deeply but distinctly einarginate ; behind it does 

 not reach to the front ocellus and has an undulating margin ; frons above the 

 callus and on the vertex brown. 



Thorax with three more brownish black than slaty grey stripes, which are 

 altogether not sharply contrasted against the narrow grey separating stripes, 

 so that these latter stand out less distinct ; the pubescence on the upper side 

 of the thorax consists of rather dense, short, depressed, wholly pale yellowish 

 hairs, between which more erect, longer, blackish hairs occur. Pleurae rather 

 pale_ grey, in the Silesian specimen with white, in the South of France 

 specimen_ with greyish white pubescence. Scutellum blackish grey, paler at 

 the margin. 



Abdomen black ; basal segment with a large triangular grey spot in each 

 hind angle and with whitish or greyish white pubescence especially obvious 



