Lydella. 301 



4. L. stabulans Meig. 



1824. Meig. Syst. Beschr. IV, 306, 15 et 1838. VII, 191, 49 {Tacliina). 

 — 1891. B. B. Denkschr. Akad. Wiss. Wien, LVIII, 317 (Dexodes). — 1907. 

 Villen. Wien Ent. Zeitg. XXVI, 256, 47 (Dexodes). — 1907. Kat. palåarkt. 

 Dipt. III, 293. ^ 1921. Baer, Zeitschr. f. angew. Ent. VII, 157. — 1924. Stein, 

 Arch. f. Naturgescli. 90, 6, 97, 10 {Ceromasia). — Tacliina lepida ? Meig. 1838. 

 1. c. VII, 191, 14. — 1910. Villen. Wien. Ent. Zeitg. XXIX, 305, 7. 



Male. Frons above about as broad as the eye, somewhat pro- 

 triiding. Cheeks distinctly narrowing downwards; jowls narrow, 

 about one fifth of the height of the eye. Orbits blackish grey, cheeks 

 greyish silvery, jowls grey; frontal stripe velvet black. Weak outer 

 vertical bristles present. Frontal bristles descending to end of second 

 antennal joint. Vibrissæ very slightly ascending. Orbits with black 

 hairs some of which are bristly; jowls black-haired. Occiput nearly 

 flat, only slightly piiffed out below, grey, with yellowish hairs and 

 black hairs behind postocular bristles. Antennæ black, third joint 

 two to two and a half times as long as second; arista somewhat 

 short, thickened in about basal half, second joint slightly elongated. 

 Palpi black, a little dilated outwards. Thorax bluish black, thinly 

 bluish grey pruinose, more pronounced in front and at the sides; 

 there are four dark stripes, the median abbreviated behind, the 

 lateral rather broad; scutellum dark. Thorax black-haired; four 

 (sometimes three) postsutural dorsocentrals, and generally three 

 præ- and three postsutural acrostichals. Scutellum with four marginal 

 bristles on each side, the lateral somewhat small, the apical pair 

 small, crossing, directed upwards. Four (or only three) sternopleural 

 bristles. Abdomen elongated conical, black and shining, the three 

 last segments with a white pruinose front band, not half as broad 

 as the segment, shifting in colour according to view; the bands are 

 interrupted in the middle, leaving a somewhat broad middle stripe 

 black. Abdomen black-haired, second segment with a pair of marginal 

 bristles, third with a pair of discai and marginal and fourth with a 

 pair of discai and a row of marginal bristles; ventral side with short 

 hairs except at the margins, and on fourth segment on each side a 

 patch of short, dense hairs. Legs black. Wings a little brownish 

 tinged; veins blackish; first posterior cell open or closed, ending 

 somewhat before apex of wing. Squamulæ yellowish. H alteres dark 

 browTi. 



Female. Similar; frons somewhat broader to about one and a 

 half times as broad as the eye. 



