Ocyptera. 125 



forming two small lamellæ with a comb of spines at apex. Legs black, 

 front femora grey pruinose on posterior side; femora with antero- 

 and postero-ventral bristles. Wings brownish tinged, more yellowish 

 at base and anterior margin; veins brown; subcostal vein ending 

 beyond medial cross-vein; first posterior cell petiolate, the peduncle 

 curved upwards, ending considerably before apex of wing; discai angle 



Fig. 22. Wing of O. brassicaria S ■ 



about rectangular, generally with a more or less short veinlet ; apical 

 and posterior cross-vein sinuate. Squamulæ white. Halteres brown. 



Female. Similar; frons somewhat broader. Of the two last 

 abdominal segments the first cylindrical, the apical not long, ending 

 with two claws. Femora almost without ventral bristles, only on 

 hind femora a posteroventral bristle. 



Length 8 — 13 mm. 



O. brassicaria is common in Denmark; Ordrup Mose, Dyrehaven, 

 Hareskov, Hillerød, Grib Skov, Nyrup Hegn, Humlebæk, Lave 

 Skov at Helsingør, Rørvig, Tisvilde, Jægerspris, and in Jutland 

 at Sønderborg and Funder near Silkeborg; the dates are ^Ve — ^"/s- 

 It occurs on various flowers, especially umbellifers, but generally 

 only singly. The species is parasitic on Dolycoris baccarum. Nielsen 

 has (Entom. Medd. 2, IV, 1909, 76) treated its biology. Only the 

 imagines of the host are infested, and there is always only one parasite 

 in each host. The parasite larva hibernates in second stage in the 

 hibernating host; when fullgrown it bores out in the beginning of 

 June and pupates in the ground, and it develops in June and July. 

 The development is irregular as to time, and possibly there may 

 be two generations in the year, one summer generation, the other 

 with the larva hibernating. The fly is probably oviparous belonging 

 to Pantel's group 9. The host is not killed by the presence of the 

 parasite and survives the boring out of the latter. 



Geographical distribution: — Europe; towards the north to 

 middle Sweden, and in Finland. 



