344 Orthorrhapha brachycera. 



little converging towards the cubital vein. Squamulæ pale yellow, 

 with a pale fringe. Halteres yellow. 



Female. Epistoma a little broader than in the male, grey, the 

 greenish ground colour shining a little through. The arista a little 

 longer than in the male. The spines below the front femora towards 

 the anterior side reaching to the apex, and besides the two rows 

 there are some spines posteriorly towards the apex; the front tibiæ 

 have two ventral rows of spines, and a row of a few bristles on the 

 dorsal side; the bristles on the posterior legs a little longer. 



Length 2,8— 5,3 mm, the female longest. 



This species besides by the two scutellar bristles is also easily 

 known by the bristles on the front coxæ. 



H. bisetus is rare in Denmark, or perhaps more correctly very 

 local; Jutland at Skagen (four specimens taken many years ago), and 

 on Læsø, in rather great number (H. J. Hansen). It occurs at sea- 

 coasts. 



Geographical distribution: — England, Denmark and Spain; it has 

 been known as common in England for more than fifty years, but it 

 was first recorded from the continent by Strobl in 1909 (Verhandl. 

 zool. bot. Gesell. Wien, 59, 192), who took it in Spain; as said above 

 it has stood undetermined in our collection for many years. 



2. H. balticus Meig. 



1824. Meig. Sysl. Beschr. IV, 66, 12 {Medeterus). — 1849. Zett. Dipt. 

 Scand. VIII, 3050,3. — 1862. Schin. F. A. I, 231. — 1903. Kat. palåarkt. 

 Dipt. II, 341. — Hijdrophorus litoreus 1838. Zett. Ins. Lapp. 700,3, p.p., 

 et 1843, Dipt. Scand. II, 443, p.p. 



Male. Head about as high as broad; vertex and frons brown. 

 Epistoma broad, bright metallic green above, whitish grey below. 



Fig. 106. Antenna of H. balticus d. X 95. 



Palpi brown. Occiput greenish or æneous, greyish pruinose; post- 

 ocular bristles black, the hairs below white. Jowls distinct, grey. 

 Antennæ black, third joint roundish, arista longer than the antennæ. 

 Thorax dark green, æneous or dark coppery, brown pruinose, especi- 



