102 Syrphidae. 



Length about 5,5 mm. 



O. geniculata is very rare in Denmark, only two specimens, both 

 females, have been taken in Lyngby Mose on ^/e 1909 and i*'/(i 1915 

 (the author); the latter specimen is remarkable as it has the upper 

 marginal cross-vein perpendicular and the lower not angular, the vena- 

 tion thus being quite as in the male. 



Geographical distribution:— The species is recorded from all 

 Europa down into Italy; towards the north to northern Sweden, and 

 in Finland; it must, however, be remembered, that it has perhaps been 

 confounded with the following species. 



3. O. intermedia n. sp, 



Orthoneura geniculata Loew, 1 857. Wien. ent. Monatschr. I, 8. — 

 Chrijsogaster geniculatus Zett. 1859. Dipt. Scand. XIII, 6025, 9, p. p. (speci- 

 mina stigmate pallescente, absque puncto basali fusco et nervo transverso 

 ordinario parum infuscalo). 



Male. This species again highly resembles the two preceding: 

 Head a little longer, about as high as broad ; the eye-suture longer, 

 longer than vertex which is longer than broad. Frons somewhat 

 arched, with a transverse depression above the antennæ and a small. 



Heads of O. intermedia. 

 Fig. 40. Male. Fig. 41. Female. 



dot-like impression above it; it is more fmely punctate than in geni- 

 culata. Epistoma much narrower than in the two preceding species, 

 about as broad as the diameter of the eye, with almost parallel 

 horders; the side dust spots small, roundish. Vertex with somewhat 

 short, yellowish hairs, frons with pale, above rather long hairs; epistoma 

 with short but distinct, pale hairs. Occiput greenish, with dark hairs 

 above, pale below. Antennæ about as in geniculata, but a little 

 larger, third joint about three times longer than broad; arista almost 

 as long as the antennæ; the antennæ are dark or blackish brown, 



