300 LEPTID^ 



discal cell are always well separated and the anal cell is obviously though 

 rather narrowly open ; fourth posterior cell sometimes slightly narrowed 

 towards the wingmargin. Squanije (alar) rather small, glassy smoky or dull 

 orange with short pale fringes. Halteres dull orange or dull yellow, but 

 with the stem sometimes darker ; knob rather large and ovate-globose. 



$ . Rather similar to the male, but the light grey frons occupying about a third of 

 the width of the head, and the frons and occiiDut rather densely beset with 

 short black bristles (except on the channel between the orbits and the 

 occiput), and these bristles (especially on the frons) mostly directed forwards. 



Thorax ashy grey with three dark stripes (not well defined) of which the 

 middle one is broad and extended to the front but abbreviated behind, 

 while the side ones are abbreviated in front and interrupted at the suture. 

 Pubescence much shorter, black and bristly. Scutellum ashy grey. 



Abdomen with less conspicuous whitish pubescence except about the base, 

 and with much shorter and mainly black dorsal bristly pubescence ; sixth 

 segment short, but more conspicuously separated from the distinct seventh 

 segment. Ovipositor with a pair of distinct outspread lamellae. 



Legs almost as in the male but with hardly any pubescence on the femora. 



Wings paler, especially about the stigma. Squamse more whitish glassy. 

 Halteres yellow. 



Length about 4 mm. 



I believe that there is no closely allied species in Europe (unless possibly 

 *S^. grisea), nor do I think that it varies, and consequently no mistake should 

 be made if attention be given to the reniform third anteunal joint and the 

 open anal cell. 



S. immaculata is very little known as a British species, but I once 

 found it in fair abundance near Seaford in Sussex on June 15, 1890, when 

 I caught numerous males but only two females. There are several 

 specimens in the British Museum from Mr A. Piffard who took them 

 on June 18, 1893, at Felden in Hertfordshire. Walker recorded it in 

 1851 as " Common in Darenth Wood, Kent," and I have no doubt correctly 

 as it was properly named in the Entomological Club collection, but though 

 I often collected there about 1870 I never met with it. It is recorded 

 from Central Europe only. 



Synonymy. — No doubt has ever arisen as to the identity of this species, but 

 Walker's character of "Abdomen clothed with short black hairs" is misleading. 

 Athei-ix nnicolor Curtis (1824) which was described as ''Male cinereous, sparingly 

 " clothed with longish pale hairs : antennae blackish, 3rd joint reniform : eye reddish- 

 " brown : thorax obscurely striped : tibiae lurid and subochreous towards the base : 

 " wings slightly fuscous, 3rd costal cell a little darker : halteres ochreous : length 3 

 " lines," taken at " Mickleham the end of June " which is not far from Darenth, 

 must be a synonym, as the reniform third antennal joint makes it a Synvphoroinyia 

 and not (as I suggested in Entom., 1890, p. 153) a Ptiolina. It is probably my error 

 which caused Bezzi in his Katalog der Paliiarktischen Dipteren, ii., 89, to assign it 

 as a synonym of Ptiolina paradoxa Jaen. I can only imagine that Ptiolina melcena 

 of Walker (Ins. Brit. Dipt., i., 71, 1851) must refer to S. immaculata, but his Atherix 

 melcena of 1836 (Entom. Mag., iii., 180) to Ptiolina obscura Fall. 



6. CHRYSOPILUS. 



Chrysopihis Macquart, Mem. Soc. Sci. Lille, 1826, 403. 



Moderate- sized to rather small flies of elongate shape, which 

 are always bedecked with recumbent golden scales or scaly 

 hairs, and which have the wings rather broad. 



