Helophilus. 453 



and Dødemose west of Nysted (L. Jørgensen); the first specimen was 

 taken in 1899. My dates are ^"'k — ^^'/o. It occurs in the same way 

 as the preceding species; in spring I have taken it on the flowers of 

 Primus spinosa. 



Geographical distribution: — Northern and middle Europe down 

 into Austria and Hungaria; towards the north to southern Sweden; 

 it occurs also in North America [novae-scotiae Macq.). 



3. H. affinis Wahlb. 



1844. Wahlb. Ofvers. Vet. Akad. Forh. I, 64. — 1849. Zett. Dipt. 

 Scand. VIII, 3119, 2—3. — 1907. Kat. palåarkt. Dipt. III, 107. — 1910. 

 Beck. Berl. ent. Zeitschr. LV, 226. — H. arcticus Zett. p. p. 1838. Ins. Lapp. 

 595, 2 et 1843. Dipt. Scand. II, 678, 2. — H. horealis Siebke (nec Stæg.), 

 1864. Nyt Mag. f. Naturv. 166 et 1877. Enum. Ins. norveg. IV, 54, 4. — 

 R. Siehkii Verr. 1 900. Gat. eur. Syrph. 86. 



This species is very similar to the two preceding. Male. Middle 

 stripe on epistoma black. Second abdominal segment a little shorter 

 than in the two preceding species, and more like that in pendulus. 

 The spots on second segment do not reach the hind margin but leave 

 a relatively broad, black margin, and there are no orange hind mar- 

 gins to the abdominal segments; the greyish yellow, somewhat pruinose 

 bands on the fourth segment are much narrower than in hyhridus 

 and less near to the front margin. Hind femora black, at most with 

 a small pale spot below the apex; front tarsi yellow or the third and 

 fourth joints darkened; hind femora not much thickened, the thickest 

 part near the apex; the legs haired mainly as in hybridus. Wing- 

 stigma brownish. 



Female. Likewise similar to the preceding species, especially to 

 hyhridus^ but differing as in the male by the narrower basal abdom- 

 inal spots, the want of orange hind margins to the segments and the 

 partly yellow front tarsi. The fifth abdominal segment has short, black 

 hairs on the apical part. 



Length 13,5 — 15 mm. 



H. affinis seems to be very rare in Denmark, we have only two 

 specimens, a male and a female; the female belongs to the specimens 

 mentioned by Zetterstedt (1. c. VIII, 3120) and was taken by Jacobsen 

 at Sorø; according to old notes from Jacobsen he took one male and 

 two females on Parnassia palustris in August and September 1845; 

 now we have only the one female, the two other specimens were 

 perhaps sent to Zetterstedt; my male specimen is taken on Lolland 

 in Vester Ulslev Mose west of Nysted on ^^h 191 4 (L. Jørgensen). 



