202 Orthorrhapha brachycera. 



lower branch of the postical vein goes downwards and meets the 

 anal vein rectangularly; the anal vein reaches the margin and is a 

 little curved at the apex. The discai cell is somewhat long; also the 



Fig. 82. Wing of O. glabricula. 



basal cells are long, and the anal cell shorter than the second basal 

 cell. Stigma present. The axiilary lobe well developed. Alula not 

 developed, the margin here fringed. Alar squamulæ small, with a long 

 fringe at the margin. 



The larva is deseribed by Beling (Arch. flir Naturgesch. 48, 1, 

 1882, 213); it is cylindrical, attenuated towards the anterior end, 

 twelve-jointed and of yellowish white colour. The last segment is 

 somewhat short and broad, and slightly, longitudinally fmTOwed; on 

 the end of it is a truncate, membranous tooth with a broad base, 

 and with the apex directed upwards; above the tooth the terminal 

 spiracles are placed. The abdominal segments have small, transverse 

 swellings (Kriechschwielen) on the ventral side. The larva is 6 nmi. 

 long and 0,6 mm. thick. The pupa is yellowish, it has two teeth on 

 the front side of the head, and some erect hairs on the head. The 

 abdominal segments have each above at the hind margin a transverse 

 row of short, brown spines. The pupa is 3 mm. long. The larvæ 

 were found on a field below decaying vegetables; the imagines de- 

 veloped on ^''/^ to ^/fi. 



The species occurs in low herbage on humid piaces in woods 

 and on meadows. It is carnivorous. Poulton (1. c.) records it from 

 England with Sciara sp. as prey. 



The genus comprises only one species, also found in Denmark. 



1. O. glabricula Fall. 



1815. Fall. Dipt. Suec. Erapid. 33, 42 (Etnpis). - 1820. Meig. Syst. 

 Beschr. II, 352,1, Tab. XXI, Fig. 23. - 1842. Stæg. Krøyer's Tidsskr. IV, 

 101. — 1842. Zett. Dipt. Scand. I, 236, 1. - 1862. Schin. F. A. 1, 82. 

 — 1 903. Kat. palåarkt. Dipt. II, 260. — Ocydromia ruficollis (non Meig.) : 

 1827. Macq. Soc. Se. Lille, 1827, 146, 2. — Ocydromia rufipes: 1820. 

 Meig. Syst. Beschr. II, 353, 3, et auct. eet. — Ocydromia scntellata: 1820. 

 Meig. Syst. Beschr. II, 354, 5, et auct. eet. — Ocydromia dorsalis: 1830. 



