Melanostoma. 233 



specimens they may be darker on the anterior feniora; also the short 

 hairs on tibiæ may vary in the same way; hind melatarsi slightly 

 thickened. Wings more or less brownish tinged. Squamulæ smoky 

 to blackish, with a darker margin and a yellow or brown fringe. 

 Halteres yellow. 



Female. Frons broad, shining, with very small side dust spots; 

 the hairs are yellow, brownish in front of the ocelli. Antennæ longer 

 than in the male, as the third joint is longer. Abdomen shining; the 

 spots of second and third pairs are on the outside sloping inwards 

 from the basal corner to the end so that they are more or less 

 triangular; at the base of the fifth segment are a pair of transverse, 

 narrow spots. Legs in so far paler than in the male as they are 

 never so dark as in the most dark-legged males, and often almost 

 quite yellow with only the ends of the tarsi darkened. 



Length 6 to about 8 mm. 



M. mellinum is very common in Denmark and has been taken in 

 all parts of our country; my dates are ^^/o — '^h. It occurs in fens, on 

 commons and meadows and also in woods. The pupæ were taken in 

 Ermelund, sitting on stalks of Carduus on ^Vt, they developed on ^^/t 

 and ^-/t (Kryger), and larvæ were taken in flood refuse at Donse and 

 in Jutland at Randers, developing in April and May (Schlick). 



Geographical distribution: — All Europe, towards the north to 

 northern Sweden, in Finland and on the Faroe Islands; further it is 

 known from the Ganary Islands and Madeira ; it is also recorded from 

 North- and Central America. 



3. M. scalare Fabr. 



1794. Fabr. Ent. Syst. IV, 308, 117 {Syrphus) et 1805. Syst. Antl. 

 252, 14 {Scaeva). — 1843. Zett. Dipt. Scand. II, 760, 63 et 1849. VIII, 

 3154, 63 {Scaeva). — 1901. Verr. Brit. Fl. VIII, 311, 4, fig. 264. — 1907. 

 Kat. palåarkt. Dipt. III, 51. — Syrphus gracilis Meig. 1822. Syst. Beschr. 

 III, 328, 80. — 1862. Schin. F. A. I, 292. — Syrphus maculosus Me\g. 

 1822. 1. c. 330, 84, ?. 



This species is much like the preceding, but it is larger and 

 abdomen longer. Male. Frons and epistoma distinctly yellowish 

 pruinose, the central knob shining. Vertex and frons with yellow or 

 brownish hairs; the whitish hairs on epistoma more scarce than in 

 mellinum. Antennæ inserted above the middle of the head, yellow 

 with the apex and upper margin of third joint brown or blackish; 

 arista yellowish or brown, distinctly though short-pubescent. Thorax 

 shining, yellow-haired, the hairs longer than in mellinum. Abdomen 

 narrower than thorax, about six times as long as broad, the three 



