432 Syrphidae. 



grey or pale yellow and broader than in the male; the pubescence 

 short and often darker than in the male, as it may vary from all 

 yellow to black on the hind margin of second and on almost the 

 whole third and the front part of fourth segment. Middle tibiæ some- 

 times pale to near the apex. 



Length 9— 12 mm. 



This species is characterised by the entirely pruinose and hairy 

 epistoma without black middle stripe and by the somewhat long-fringed 

 anterior tibiæ; these characters are found only in one other species, 

 lucorum, but that species has a pubescent arista, the hairs on femora 

 longer, and in the female the abdominal spots quite shining. 



E. arhustorum is very common in Denmark over the whole country. 

 My dates are ^'^U—'^-^h. It occurs in fens, on commons and meadows 

 and in woods and thickets, especially at ponds and ditches and on 

 similar piaces, and it frequents many various flowers. I have taken 

 the pupa in a cloaca in Copenhagen on '^Ib, it developed at the middle 

 of the month. 



Geograpiiical distribution : — All Europe and down into Syria and 

 North Africa; towards the north to northern Sweden, in Finland, 

 Siberia and on the Faroe Islands. 



10. E. pertinax Scop. 



1763. Scop. Entom. Garn. 352, 954 (Conops). — 1862. Schin. F. A. I, 

 336. — 1901. Verr. Brit. FI. VIII, 513, 7. — 1907. Kat. palåarkt. Dipt. III, 

 106. — Syrphus similis Fall. 1817. Dipt. Suec. Syrph. 25, 16. — 1822. 

 Meig. Syst. Beschr. III, 392, 13 {Eristalis). — 1843. Zett. Dipt. Scand. Il, 

 660, 6 et 1855. XII, 4651, 6 (Syrphus). — E. fossarum Meig. 1822. 1. c. 

 III, 393, 15. — Syrphus flavitarsis Malm, 1860. K. V. och V. Sarah. Gote- 

 borg. Handl. VII, 17. 



Male. Vertex blackish, slightly pruinose ; frons yellowish or greyish 

 yellow pruinose with a black, triangular space above the antennæ; 

 epistoma yellowish pruinose with a very or exceedingly narrow (in 

 intact specimens) black middle stripe not reaching the antennæ and 

 not going below the central knob, the lower side parts black; jowls 

 black, a little pruinose. Vertex with yellow, anteriorly black hairs, 

 frons black-haired and epistoma with yellow hairs ; the latter is sligthly 

 and evenly hollowed from the antennæ to the small central knob 

 below which it is somewhat retreating, and it is somewhat descending. 

 Occiput greyish pruinose, whitish or silvery along the eye-margin to 

 above the middle and then brownish black; the hairs yellow, above 

 some black hairs. Eyes with yellowish brown hairs. Antennæ brownish 

 to black, third joint longer than broad with the end rounded; arista 



