318 Orthorrhapha brachycera. 



1. M. plumbellus Meig. 



1824. Meig. Syst. Beschr. IV, 69,20. — 1857. Loew, Neue Beitr.V, 54. — 

 1862. Schin. F. A. 1, 238. — 1877. Kow. Verh. zool. bot. Gesel!. Wien, 

 XXVII, 45, 1. — 1903. Kat. palaarkt. Dipt. II, 339. — Hydrophorus ja- 

 culiis Fall. 1823. Dipt. Suec. Dol. 5, 7, p. p. var. ;-. — Hydrophorus minutus 

 Zett. 1843. Dipt. Scand. II, 456, 17, et 1855. XII, 4616,17, et 1859. XIII, 

 5028, 17. 



Male. Vertex and frons greyish white or yellowish. Epistoma 

 silvery white. Palpi wliitish. Occiput brownish grey ; postocular bristles 

 whitish. Antennæ black or brownish black, third joint short; arista 

 almost apical, more than twice as long as the antennæ. Thorax light 

 grey pruinosc, generally with a middle stripe and the sides yellowish 

 brown, or the thorax upon the whole more yellowish brown, especially 

 in the male, and generally so on the posterior part and at the maigin 

 of the scutellum; acrostichal hairs very short; three dorsocentral 

 bristles. Scutellum with two brisles. Pleura light grey, seen from 

 behind the metallic green ground colour may be seen; propleura with 

 two or three white prothoracic bristles. Abdomen light grey pruinose, 

 seen from behind the metallic green ground colour is distinct; it is 

 clothed with short, whitish yellow hairs, slightly longer at the hind 

 margins of the segments and somewhat longer on the first segment. 

 Venter light grey, with whitish hairs. Hypopygium somewhat large, 

 blackish; the eighth segment greyish pruinose; ventral lobes long, 

 band-shaped, the outer lamellæ shorter, both pairs brownish, the 

 amellæ pale-haired. Legs yellow, posterior coxæ grey; front coxæ a 

 little greyish at the base and whitish pruinose anteriorly; the femora 

 may be a little brownish at the base; the very apex of the tibiæ, the 

 apex of the first tarsal joints and the whole fifth, or fourth and fifth 

 joint blackish; hind metatarsus not half as long as the second joint, 

 excised at the base below, and with a small tooth, and besides with 

 a brush of short, black hairs above at the extreme base. The legs 

 have short, pale hairs; the anterior coxæ have bristly hairs, the hind 

 coxæ one bristle on the outer side, all whitish; the hairs below the 

 femora short and fine, hind femora with longer hairs above on the 

 basal part ; middle tibiæ with two black dorsal bristles near the base, 

 hind tibiæ with one small. Wings yellowish tinged; veins blackish 

 brown, the last part of the discai vein straight, not much converging 

 towards the cubital vein; the last part of the postical vein about as 

 long as the cross-vein. Squamulæ yellow, with a white fringe. Bal- 

 teres pale yellow. 



Female. Epistoma slightly broader than in the male. Thorax as 

 in the male generally with somewhat distinct yellowish brown middle 



