520 Syrphidae. 



not very oblique but placed after the middle of the discai cell. 

 Stigma brown. Squamulæ dirty whitish or smoky, with dark margin 

 and fringes. Halteres with yellow peduncle and blackish knob. 



Female. Similar to the male; vertex and frons somewhat broad, 

 widening downwards; they are black and shining, the frons with two 

 small, greyish side dust spots; the hairs black, the space above the 

 antennæ bare. Thorax and scutellum more short-haired than in the 

 male, Abdomen with the fourth segment long but shorter than in 

 the male. Hind femora a little less thickened than in the male but 

 otherwise similar. 



Length 12 to fully 14 mm. 



X.femorata is rather rare in Denmark; Tyvekrog (the author), 

 Tisvilde (J. G. Nielsen, the author), and a few specimens from earlier 

 times without particular locality. My dates are ^/e— ^Vv. It seems to 

 occur in more extended woods and has been taken sitting on tree- 

 stubs; it is also else recorded from such localities, often sitting on 

 felled trees. 



Geographical distribution: — Northern and middle Europe down 

 into France; towards the north to northern Sweden, in Finland, and 

 in Siberia and down towards Ghina. 



6. X. sylvarum L. 



1758. Linn. Syst. Nat. X, 592 et 1767. XII, 2, 985, 37 et 1761. Fn. 

 Suec. 1804 {Musca). — 1775. Fabr. Syst. Entom. 767, 20 (Syrphus) et 1805. 

 Syst. Antl. 191,13 {Milesia). — 1816. Fall. Dipt. Suec. Syrph. 10, 4 (Milesia). 

 — 1822. Meig. Syst. Beschr. III, 223, 17. — 1843. Zett. Dipt. Scand. II, 

 870, 2. — 1862. Schin. F. A. I, 356. — 1901. Verr. Brit. FL VIII, 602, 4, 

 fig. 412. — 1907. Kat. palåarkt. Dipt. III, 131. 



Male. Vertex black or bluish black, somewhat elongated, frons 

 and epistoma yellow pruinose, the former black and shining just above 

 the antennæ; vertex with yellow hairs, frons and epistoma bare with 

 only slight, pale hairs down just along the eye-margins. Occiput 

 whitish grey pruinose on the lower part, bluish black and shining 

 above; the hairs are whitish below, yellow above. Antennæ blackish, 

 third joint generally brown or blackish brown; arista long, black. 

 Thorax æneous, shining, punctate, inwards to the humeri a greyish 

 pruinose spot; it is clothed with short, yellow hairs and with a little 

 longer, erect, likewise yellow hairs ; these latter are long on the hinder 

 part; behind on the middle of the disc both the short and long hairs 

 are more or less black; on the præalar and postalar calli are longer, 

 yellow hairs, on the latter black anteriorly, and above the wing-root 

 are somewhat strong, black hairs Scutellum with short, decumbent. 



